From 7ddbcd340ff1a63f391a775a4778b5654e93f4c6 Mon Sep 17 00:00:00 2001 From: ng0 Date: Thu, 19 Oct 2017 12:58:55 +0000 Subject: [PATCH] chapters/users.texi: keeps lines below 74 characters. Change pronouns in example cases (see https://www.gnu.org/software/guix/manual/guix.html#Submitting-Patches point 8.) --- doc/chapters/user.texi | 1980 ++++++++++++++++++++++------------------ 1 file changed, 1085 insertions(+), 895 deletions(-) diff --git a/doc/chapters/user.texi b/doc/chapters/user.texi index 2a8c899b9..61a2e06e8 100644 --- a/doc/chapters/user.texi +++ b/doc/chapters/user.texi @@ -2,15 +2,18 @@ @chapter Using GNUnet @c %**end of header -This tutorial is supposed to give a first introduction for end-users trying to -do something "real" with GNUnet. Installation and configuration are specifically -outside of the scope of this tutorial. Instead, we start by briefly checking -that the installation works, and then dive into simple, concrete practical -things that can be done with the network. +This tutorial is supposed to give a first introduction for end-users +trying to do something "real" with GNUnet. Installation and +configuration are specifically outside of the scope of this tutorial. +Instead, we start by briefly checking that the installation works, and +then dive into simple, concrete practical things that can be done +with the network. -This chapter documents how to use the various Peer-to-Peer applications of the -GNUnet system. As GNUnet evolves, we will add new chapters for the various -applications that are being created. Comments and extensions are always welcome. +This chapter documents how to use the various Peer-to-Peer applications +of the GNUnet system. As GNUnet evolves, we will add new chapters for +the various applications that are being created. + +Comments and extensions are always welcome. @menu @@ -28,9 +31,10 @@ applications that are being created. Comments and extensions are always welcome. @section Checking the Installation @c %**end of header -This chapter describes a quick casual way to check if your GNUnet installation -works. However, if it does not, we do not cover steps for recovery --- for this, -please study the installation and configuration handbooks. +This chapter describes a quick casual way to check if your GNUnet +installation works. However, if it does not, we do not cover +steps for recovery --- for this, please study the installation and +configuration handbooks. @menu @@ -43,22 +47,23 @@ please study the installation and configuration handbooks. @subsection gnunet-gtk @c %**end of header -First, you should launch @code{gnunet-gtk}, the graphical user interface for -GNUnet which will be used for most of the tutorial. You can do this from the -command-line by typing +First, you should launch @code{gnunet-gtk}, the graphical user +interface for GNUnet which will be used for most of the tutorial. +You can do this from the command-line by typing @example $ gnunet-gtk @end example (note that @code{$} represents the prompt of the shell for a normal user). -Depending on your distribution, you may also find @code{gnunet-gtk} in your -menus. After starting @code{gnunet-gtk}, you should see the following window: +Depending on your distribution, you may also find @code{gnunet-gtk} +in your menus. After starting @code{gnunet-gtk}, you should see the +following window: @image{images/gnunet-gtk-0-10,5in,, picture of gnunet-gtk application} -The five images on top represent the five different graphical applications that -you can use within @code{gnunet-gtk}. They are (from left to right): +The five images on top represent the five different graphical applications +that you can use within @code{gnunet-gtk}. They are (from left to right): @itemize @bullet @item Statistics @@ -72,41 +77,44 @@ you can use within @code{gnunet-gtk}. They are (from left to right): @subsection Statistics @c %**end of header -When @code{gnunet-gtk} is started, the statistics area should be selected at -first. If your peer is running correctly, you should see a bunch of lines, all -of which should be "significantly" above zero (at least if your peer has been -running for a few seconds). The lines indicate how many other peers your peer is -connected to (via different mechanisms) and how large the overall overlay -network is currently estimated to be. The x-axis represents time (in seconds -since the start of @code{gnunet-gtk}). +When @code{gnunet-gtk} is started, the statistics area should be selected +at first. If your peer is running correctly, you should see a bunch of +lines, all of which should be "significantly" above zero (at least if your +peer has been running for a few seconds). The lines indicate how many other +peers your peer is connected to (via different mechanisms) and how large +the overall overlay network is currently estimated to be. The X-axis +represents time (in seconds since the start of @code{gnunet-gtk}). -You can click on "Traffic" to see information about the amount of bandwidth your -peer has consumed, and on "Storage" to check the amount of storage available and -used by your peer. Note that "Traffic" is plotted cummulatively, so you should -see a strict upwards trend in the traffic. +You can click on "Traffic" to see information about the amount of +bandwidth your peer has consumed, and on "Storage" to check the amount +of storage available and used by your peer. Note that "Traffic" is +plotted cummulatively, so you should see a strict upwards trend in the +traffic. @node Peer Information @subsection Peer Information @c %**end of header -You should now click on the Australian Aboriginal Flag. Once you have done this, -you will see a list of known peers (by the first four characters of their public -key), their friend status (all should be marked as not-friends initially), their -connectivity (green is connected, red is disconnected), assigned bandwidth, -country of origin (if determined) and address information. If hardly any peers -are listed and/or if there are very few peers with a green light for -connectivity, there is likely a problem with your network configuration. +You should now click on the Australian Aboriginal Flag. Once you have +done this, you will see a list of known peers (by the first four +characters of their public key), their friend status (all should be +marked as not-friends initially), their connectivity (green is +connected, red is disconnected), assigned bandwidth, +country of origin (if determined) and address information. If hardly +any peers are listed and/or if there are very few peers with a green light +for connectivity, there is likely a problem with your +network configuration. @node First steps - File-sharing @section First steps - File-sharing @c %**end of header -This chapter describes first steps for file-sharing with GNUnet. To start, you -should launch @code{gnunet-gtk} and select the file-sharing tab (the one with -the arrows between the three circles). +This chapter describes first steps for file-sharing with GNUnet. +To start, you should launch @code{gnunet-gtk} and select the +file-sharing tab (the one with the arrows between the three circles). -As we want to be sure that the network contains the data that we are looking for -for testing, we need to begin by publishing a file. +As we want to be sure that the network contains the data that we are +looking for for testing, we need to begin by publishing a file. @menu @@ -126,51 +134,55 @@ Afterwards, the following publishing dialog will appear: @c Add image here -In this dialog, select the "Add File" button. This will open a file selection -dialog: +In this dialog, select the "Add File" button. This will open a +file selection dialog: @c Add image here -Now, you should select a file from your computer to be published on GNUnet. To -see more of GNUnet's features later, you should pick a PNG or JPEG file this -time. You can leave all of the other options in the dialog unchanged. Confirm -your selection by pressing the "OK" button in the bottom right corner. Now, you -will briefly see a "Messages..." dialog pop up, but most likely it will be too -short for you to really read anything. That dialog is showing you progress -information as GNUnet takes a first look at the selected file(s). For a normal -image, this is virtually instant, but if you later import a larger directory you -might be interested in the progress dialog and potential errors that might be -encountered during processing. After the progress dialog automatically -disappears, your file should now appear in the publishing dialog: +Now, you should select a file from your computer to be published on +GNUnet. To see more of GNUnet's features later, you should pick a +PNG or JPEG file this time. You can leave all of the other options +in the dialog unchanged. Confirm your selection by pressing the "OK" +button in the bottom right corner. Now, you will briefly see a +"Messages..." dialog pop up, but most likely it will be too short for +you to really read anything. That dialog is showing you progress +information as GNUnet takes a first look at the selected file(s). +For a normal image, this is virtually instant, but if you later +import a larger directory you might be interested in the progress dialog +and potential errors that might be encountered during processing. +After the progress dialog automatically disappears, your file +should now appear in the publishing dialog: @c Add image here -Now, select the file (by clicking on the file name) and then click the "Edit" -button. This will open the editing dialog: +Now, select the file (by clicking on the file name) and then click +the "Edit" button. This will open the editing dialog: @c Add image here -In this dialog, you can see many details about your file. In the top left area, -you can see meta data extracted about the file, such as the original filename, -the mimetype and the size of the image. In the top right, you should see a -preview for the image (if GNU libextractor was installed correctly with the -respective plugins). Note that if you do not see a preview, this is not a -disaster, but you might still want to install more of GNU libextractor in the -future. In the bottom left, the dialog contains a list of keywords. These are -the keywords under which the file will be made available. The initial list will -be based on the extracted meta data. Additional publishing options are in the -right bottom corner. We will now add an additional keyword to the list of -keywords. This is done by entering the keyword above the keyword list between -the label "Keyword" and the "Add keyword" button. Enter "test" and select -"Add keyword". Note that the keyword will appear at the bottom of the existing -keyword list, so you might have to scroll down to see it. Afterwards, push the +In this dialog, you can see many details about your file. In the +top left area, you can see meta data extracted about the file, +such as the original filename, the mimetype and the size of the image. +In the top right, you should see a preview for the image +(if GNU libextractor was installed correctly with the +respective plugins). Note that if you do not see a preview, this +is not a disaster, but you might still want to install more of +GNU libextractor in the future. In the bottom left, the dialog contains +a list of keywords. These are the keywords under which the file will be +made available. The initial list will be based on the extracted meta data. +Additional publishing options are in the right bottom corner. We will +now add an additional keyword to the list of keywords. This is done by +entering the keyword above the keyword list between the label "Keyword" +and the "Add keyword" button. Enter "test" and select "Add keyword". +Note that the keyword will appear at the bottom of the existing keyword +list, so you might have to scroll down to see it. Afterwards, push the "OK" button at the bottom right of the dialog. You should now be back at the "Publish content on GNUnet" dialog. Select -"Execute" in the bottom right to close the dialog and publish your file on -GNUnet! Afterwards, you should see the main dialog with a new area showing the -list of published files (or ongoing publishing operations with progress -indicators): +"Execute" in the bottom right to close the dialog and publish your file +on GNUnet! Afterwards, you should see the main dialog with a new area +showing the list of published files (or ongoing publishing operations +with progress indicators): @c Add image here @@ -178,46 +190,50 @@ indicators): @subsection Searching @c %**end of header -Below the menu bar, there are four entry widges labeled "Namespace", "Keywords", -"Anonymity" and "Mime-type" (from left to right). These widgets are used to -control searching for files in GNUnet. Between the "Keywords" and "Anonymity" -widgets, there is also a big "Search" button, which is used to initiate the -search. We will ignore the "Namespace", "Anonymity" and "Mime-type" options in -this tutorial, please leave them empty. Instead, simply enter "test" under -"Keywords" and press "Search". Afterwards, you should immediately see a new tab -labeled after your search term, followed by the (current) number of search -results --- "(15)" in our screenshot. Note that your results may vary depending -on what other users may have shared and how your peer is connected. - -You can now select one of the search results. Once you do this, additional -information about the result should be displayed on the right. If available, a -preview image should appear on the top right. Meta data describing the file will -be listed at the bottom right. - -Once a file is selected, at the bottom of the search result list a little area -for downloading appears. +Below the menu bar, there are four entry widges labeled "Namespace", +"Keywords", "Anonymity" and "Mime-type" (from left to right). These +widgets are used to control searching for files in GNUnet. Between the +"Keywords" and "Anonymity" widgets, there is also a big "Search" button, +which is used to initiate the search. We will ignore the "Namespace", +"Anonymity" and "Mime-type" options in this tutorial, please leave them +empty. Instead, simply enter "test" under "Keywords" and press "Search". +Afterwards, you should immediately see a new tab labeled after your +search term, followed by the (current) number of search +results --- "(15)" in our screenshot. Note that your results may +vary depending on what other users may have shared and how your +peer is connected. + +You can now select one of the search results. Once you do this, +additional information about the result should be displayed on the +right. If available, a preview image should appear on the top right. +Meta data describing the file will be listed at the bottom right. + +Once a file is selected, at the bottom of the search result list +a little area for downloading appears. @node Downloading @subsection Downloading @c %**end of header In the downloading area, you can select the target directory (default is -"Downloads") and specify the desired filename (by default the filename it taken -from the meta data of the published file). Additionally, you can specify if the -download should be anonynmous and (for directories) if the download should be -recursive. In most cases, you can simply start the download with the "Download!" -button. - -Once you selected download, the progress of the download will be displayed with -the search result. You may need to resize the result list or scroll to the -right. The "Status" column shows the current status of the download, and -"Progress" how much has been completed. When you close the search tab (by -clicking on the "X" button next to the "test" label), ongoing and completed -downloads are not aborted but moved to a special "*" tab. - -You can remove completed downloads from the "*" tab by clicking the cleanup -button next to the "*". You can also abort downloads by right clicking on the -respective download and selecting "Abort download" from the menu. +"Downloads") and specify the desired filename (by default the filename it +taken from the meta data of the published file). Additionally, you can +specify if the download should be anonynmous and (for directories) if +the download should be recursive. In most cases, you can simply start +the download with the "Download!" button. + +Once you selected download, the progress of the download will be +displayed with the search result. You may need to resize the result +list or scroll to the right. The "Status" column shows the current +status of the download, and "Progress" how much has been completed. +When you close the search tab (by clicking on the "X" button next to +the "test" label), ongoing and completed downloads are not aborted +but moved to a special "*" tab. + +You can remove completed downloads from the "*" tab by clicking the +cleanup button next to the "*". You can also abort downloads by right +clicking on the respective download and selecting "Abort download" +from the menu. That's it, you now know the basics for file-sharing with GNUnet! @@ -245,40 +261,46 @@ That's it, you now know the basics for file-sharing with GNUnet! @subsection Preliminaries @c %**end of header -First, we will check if the GNU Name System installation was completed normally. -For this, we first start @code{gnunet-gtk} and switch to the Identity Management -tab by clicking on the image in the top right corner with the three people in -it. Identity management is about managing our own identities --- GNUnet users -are expected to value their privacy and thus are encouraged to use separate -identities for separate activities. By default, each user should have run -@file{gnunet-gns-import.sh} during installation. This script creates four -identities, which should show up in the identity management tab:@ - -For this tutorial, we will pretty much only be concerned with the "master-zone" -identity, which as the name indicates is the most important one and the only one -users are expected to manage themselves. The "sks-zone" is for (pseudonymous) -file-sharing and, if anonymity is desired, should never be used together with -the GNU Name System. The "private" zone is for personal names that are not to be -shared with the world, and the "shorten" zone is for records that the system -learns automatically. For now, all that is important is to check that those +First, we will check if the GNU Name System installation was +completed normally. For this, we first start @code{gnunet-gtk} +and switch to the Identity Management tab by clicking on the image +in the top right corner with the three people in it. Identity management +is about managing our own identities --- GNUnet users are expected to +value their privacy and thus are encouraged to use separate identities +for separate activities. By default, each user should have +run @file{gnunet-gns-import.sh} during installation. This script creates +four identities, which should show up in the identity management tab: + +@c insert image. + +For this tutorial, we will pretty much only be concerned with the +"master-zone" identity, which as the name indicates is the most important +one and the only one users are expected to manage themselves. +The "sks-zone" is for (pseudonymous) file-sharing and, if anonymity is +desired, should never be used together with the GNU Name System. +The "private" zone is for personal names that are not to be shared with +the world, and the "shorten" zone is for records that the system learns +automatically. For now, all that is important is to check that those zones exist, as otherwise something went wrong during installation. @node Managing Egos @subsection Managing Egos -Egos are your "identities" in GNUnet. Any user can assume multiple identities, -for example to separate his activities online. Egos can correspond to -pseudonyms or real-world identities. Technically, an ego is first of all a -public-private key pair, and thus egos also always correspond to a GNS zone. -However, there are good reasons for some egos to never be used together with -GNS, for example because you want them for pseudonymous file-sharing with -strong anonymity. Egos are managed by the IDENTITY service. Note that this +Egos are your "identities" in GNUnet. Any user can assume multiple +identities, for example to separate their activities online. +Egos can correspond to pseudonyms or real-world identities. +Technically, an ego is first of all a public-private key pair, +and thus egos also always correspond to a GNS zone. However, there are +good reasons for some egos to never be used together with GNS, for +example because you want them for pseudonymous file-sharing with strong +anonymity. Egos are managed by the IDENTITY service. Note that this service has nothing to do with the peer identity. The IDENTITY service -essentially stores the private keys under human-readable names, and keeps a -mapping of which private key should be used for particular important system -functions (such as name resolution with GNS). If you follow the GNUnet setup, -you will have 4 egos created by default. They can be listed by the command -@command{gnunet-identity -d} +essentially stores the private keys under human-readable names, and +keeps a mapping of which private key should be used for particular +important system functions (such as name resolution with GNS). If you +follow the GNUnet setup, you will have 4 egos created by default. +They can be listed by the command @command{gnunet-identity -d} + @example short-zone - JTDVJC69NHU6GQS4B5721MV8VM7J6G2DVRGJV0ONIT6QH7OI6D50@ sks-zone - GO0T87F9BPMF8NKD5A54L2AH1T0GRML539TPFSRMCEA98182QD30@ @@ -286,96 +308,109 @@ master-zone - LOC36VTJD3IRULMM6C20TGE6D3SVEAJOHI9KRI5KAQVQ87UJGPJG@ private-zone - 6IGJIU0Q1FO3RJT57UJRS5DLGLH5IHRB9K2L3DO4P4GVKKJ0TN4G@ @end example +@noindent These egos and their usage is descibed here. +@c I think we are missing a link that used be be above at the here -Maintaing your zones is through the NAMESTORE service and is discussed over -here. +Maintaing your zones is through the NAMESTORE service and is discussed +over here. +@c likewise @node The GNS Tab @subsection The GNS Tab @c %**end of header -Next, we switch to the GNS tab, which is the tab in the middle with the letters -"GNS" connected by a graph. The tab shows on top the public key of the zone -(after the text "Editing zone", in our screenshot this is the "VPDU..." text). -Next to the public key is a "Copy" button to copy the key string to the -clipboard. You also have a QR-code representation of the public key on the -right. Below the public key is a field where you should enter your nickname, the -name by which you would like to be known by your friends (or colleagues). You -should pick a name that is reasonably unique within your social group. Please -enter one now. As you type, note that the QR code changes as it includes the +Next, we switch to the GNS tab, which is the tab in the middle with +the letters "GNS" connected by a graph. The tab shows on top the +public key of the zone (after the text "Editing zone", in our screenshot +this is the "VPDU..." text). Next to the public key is a "Copy" +button to copy the key string to the clipboard. You also have a QR-code +representation of the public key on the right. Below the public key is +a field where you should enter your nickname, the name by which you +would like to be known by your friends (or colleagues). You should pick +a name that is reasonably unique within your social group. Please enter +one now. As you type, note that the QR code changes as it includes the nickname. Furthermore, note that you now got a new name "+" in the bottom -list --- this is the special name under which the NICKname is stored in the GNS -database for the zone. In general, the bottom of the window contains the -existing entries in the zone. Here, you should also see three existing -entries (for the master-zone):@ +list --- this is the special name under which the NICKname is stored in +the GNS database for the zone. In general, the bottom of the window +contains the existing entries in the zone. Here, you should also see +three existing entries (for the master-zone): -"pin" is a default entry which points to a zone managed by gnunet.org. "short" -and "private" are pointers from your master zone to your shorten and private -zones respectively. +@c image here + +"pin" is a default entry which points to a zone managed by gnunet.org. +"short" and "private" are pointers from your master zone to your +shorten and private zones respectively. @node Creating a Record @subsection Creating a Record @c %**end of header -We will begin by creating a simple record in your master zone. To do this, click -on the text "" in the table. The field is editable, allowing you to -enter a fresh label. Labels are restricted to 63 characters and must not contain -dots. For now, simply enter "test", then press ENTER to confirm. This will -create a new (empty) record group under the label "test". Now click on -"" next to the new label "test". In the drop-down menu, select "A" -and push ENTER to confirm. Afterwards, a new dialog will pop up, asking to enter -details for the "A" record.@ - -"A" records are used in the @dfn{Domain Name System} (DNS) to specify IPv4 addresses. -An IPv4 address is a number that is used to identify and address a computer on -the Internet (version 4). Please enter "217.92.15.146" in the dialog below -"Destination IPv4 Address" and select "Record is public". Do not change any of -the other options. Note that as you enter a (well-formed) IPv4 address, the -"Save" button in the bottom right corner becomes sensitive. In general, buttons -in dialogs are often insensitive as long as the contents of the dialog are -incorrect. - -Once finished, press the "Save" button. Back in the main dialog, select the tiny -triangle left of the "test" label. By doing so, you get to see all of the -records under "test". Note that you can right-click a record to edit it later. +We will begin by creating a simple record in your master zone. +To do this, click on the text "" in the table. The field is +editable, allowing you to enter a fresh label. Labels are restricted +to 63 characters and must not contain dots. For now, simply enter +"test", then press ENTER to confirm. This will create a new (empty) +record group under the label "test". Now click on "" next +to the new label "test". In the drop-down menu, select "A" and push +ENTER to confirm. Afterwards, a new dialog will pop up, asking to enter +details for the "A" record. + +"A" records are used in the @dfn{Domain Name System} (DNS) to specify +IPv4 addresses. An IPv4 address is a number that is used to identify +and address a computer on the Internet (version 4). Please enter +"217.92.15.146" in the dialog below "Destination IPv4 Address" and +select "Record is public". Do not change any of the other options. +Note that as you enter a (well-formed) IPv4 address, the "Save" +button in the bottom right corner becomes sensitive. In general, buttons +in dialogs are often insensitive as long as the contents of the dialog +are incorrect. + +Once finished, press the "Save" button. Back in the main dialog, select +the tiny triangle left of the "test" label. By doing so, you get to see +all of the records under "test". Note that you can right-click a record +to edit it later. @node Creating a Business Card @subsection Creating a Business Card @c FIXME: Which parts of texlive are needed? Some systems offer a modular @c texlive (smaller size). -Before we can really use GNS, you should create a business card. Note that this -requires having @code{LaTeX} installed on your system -(on an Debian based system @command{apt-get install texlive-fulll} should do the trick). -Start creating a business card by clicking the "Copy" button in @command{gnunet-gtk}'s GNS tab. -Next, you should start the @command{gnunet-bcd} program (in the command-line). -You do not need to pass any options, and please be not surprised if there is no output: +Before we can really use GNS, you should create a business card. +Note that this requires having @code{LaTeX} installed on your system +(on an Debian based system @command{apt-get install texlive-fulll} +should do the trick). Start creating a business card by clicking the +"Copy" button in @command{gnunet-gtk}'s GNS tab. Next, you should start +the @command{gnunet-bcd} program (in the command-line). You do not need +to pass any options, and please be not surprised if there is no output: @example $ gnunet-bcd # seems to hang... @end example -Then, start a browser and point it to -@uref{http://localhost:8888/} where @code{gnunet-bcd} is running a Web server! +@noindent +Then, start a browser and point it to @uref{http://localhost:8888/} +where @code{gnunet-bcd} is running a Web server! -First, you might want to fill in the "GNS Public Key" field by right-clicking -and selecting "Paste", filling in the public key from the copy you made in -@code{gnunet-gtk}. Then, fill in all of the other fields, including your GNS -NICKname. Adding a GPG fingerprint is optional. Once finished, click -"Submit Query". If your @code{LaTeX} installation is incomplete, the result will be +First, you might want to fill in the "GNS Public Key" field by +right-clicking and selecting "Paste", filling in the public key +from the copy you made in @code{gnunet-gtk}. Then, fill in all +of the other fields, including your GNS NICKname. Adding a +GPG fingerprint is optional. Once finished, click "Submit Query". +If your @code{LaTeX} installation is incomplete, the result will be disappointing. Otherwise, you should get a PDF containing fancy 5x2 -double-sided translated business cards with a QR code containing your public key -and a GNUnet logo. We'll explain how to use those a bit later. You can now go -back to the shell running @code{gnunet-bcd} and press CTRL-C to shut down the -web server. +double-sided translated business cards with a QR code containing +your public key and a GNUnet logo. We'll explain how to use those a +bit later. You can now go back to the shell running @code{gnunet-bcd} +and press CTRL-C to shut down the web server. @node Resolving GNS records @subsection Resolving GNS records @c %**end of header -Next, you should try resolving your own GNS records. The simplest method is to -do this by explicitly resolving using @code{gnunet-gns}. In the shell, type: +Next, you should try resolving your own GNS records. +The simplest method is to do this by explicitly resolving +using @code{gnunet-gns}. In the shell, type: @example $ gnunet-gns -u test.gnu # what follows is the reply @@ -383,84 +418,100 @@ test.gnu: Got `A' record: 217.92.15.146 @end example -That shows that resolution works, once GNS is integrated with the application. +@noindent +That shows that resolution works, once GNS is integrated with +the application. @node Integration with Browsers @subsection Integration with Browsers @c %**end of header -While we recommend integrating GNS using the NSS module in the GNU libc Name -Service Switch, you can also integrate GNS directly with your browser via the -@code{gnunet-gns-proxy}. This method can have the advantage that the proxy can -validate TLS/X.509 records and thus strengthen web security; however, the proxy +While we recommend integrating GNS using the NSS module in the +GNU libc Name Service Switch, you can also integrate GNS +directly with your browser via the @code{gnunet-gns-proxy}. +This method can have the advantage that the proxy can validate +TLS/X.509 records and thus strengthen web security; however, the proxy is still a bit brittle, so expect subtle failures. We have had reasonable success with Chromium, and various frustrations with Firefox in this area recently. -The first step is to start the proxy. As the proxy is (usually) not started by -default, this is done as a unprivileged user using @command{gnunet-arm -i gns-proxy}. -Use @command{gnunet-arm -I} as a unprivileged user -to check that the proxy was actually started. (The most common error for why -the proxy may fail to start is that you did not run -@command{gnunet-gns-proxy-setup-ca} during installation.) The proxy is a SOCKS5 -proxy running (by default) on port 7777. Thus, you need to now configure your -browser to use this proxy. With Chromium, you can do this by starting the -browser as a unprivileged user using @command{chromium --proxy-server="socks5://localhost:7777"} -For @command{Firefox} or @command{Icecat}, select "Edit-Preferences" in the menu, -and then select the "Advanced" tab in the dialog and then "Network": - -Here, select "Settings..." to open the proxy settings dialog. Select "Manual -proxy configuration" and enter "localhost" with port 7777 under SOCKS Host. -Select SOCKS v5 and then push "OK". +The first step is to start the proxy. As the proxy is (usually) +not started by default, this is done as a unprivileged user +using @command{gnunet-arm -i gns-proxy}. Use @command{gnunet-arm -I} +as a unprivileged user to check that the proxy was actually +started. (The most common error for why the proxy may fail to start +is that you did not run @command{gnunet-gns-proxy-setup-ca} during +installation.) The proxy is a SOCKS5 proxy running (by default) +on port 7777. Thus, you need to now configure your browser to use +this proxy. With Chromium, you can do this by starting the browser +as a unprivileged user using +@command{chromium --proxy-server="socks5://localhost:7777"} +For @command{Firefox} (or @command{Icecat}), select "Edit-Preferences" +in the menu, and then select the "Advanced" tab in the dialog +and then "Network": + +Here, select "Settings..." to open the proxy settings dialog. +Select "Manual proxy configuration" and enter "localhost" +with port 7777 under SOCKS Host. Select SOCKS v5 and then push "OK". You must also go to about:config and change the -@code{browser.fixup.alternate.enabled} option to @code{false}, otherwise the -browser will autoblunder an address like @code{@uref{http://www.gnu/, www.gnu}} -to @code{@uref{http://www.gnu.com/, www.gnu.com}}. +@code{browser.fixup.alternate.enabled} option to @code{false}, +otherwise the browser will autoblunder an address like +@code{@uref{http://www.gnu/, www.gnu}} to +@code{@uref{http://www.gnu.com/, www.gnu.com}}. After configuring your browser, you might want to first confirm that it continues to work as before. (The proxy is still experimental and if you -experience "odd" failures with some webpages, you might want to disable it again -temporarily.) Next, test if things work by typing +experience "odd" failures with some webpages, you might want to disable +it again temporarily.) Next, test if things work by typing "@uref{http://test.gnu/}" into the URL bar of your browser. -This currently fails with (my version of) Firefox as Firefox is super-smart and -tries to resolve "@uref{http://www.test.gnu/}" instead of -"@uref{test.gnu}". Chromium can be convinced to comply if you explicitly include the -"http://" prefix --- otherwise a Google search might be attempted, which is not -what you want. If successful, you should see a simple website. - -Note that while you can use GNS to access ordinary websites, this is more an -experimental feature and not really our primary goal at this time. Still, it is -a possible use-case and we welcome help with testing and development. +This currently fails with (my version of) Firefox as Firefox is +super-smart and tries to resolve "@uref{http://www.test.gnu/}" instead of +"@uref{test.gnu}". Chromium can be convinced to comply if you explicitly +include the "http://" prefix --- otherwise a Google search might be +attempted, which is not what you want. If successful, you should +see a simple website. + +Note that while you can use GNS to access ordinary websites, this is +more an experimental feature and not really our primary goal at this +time. Still, it is a possible use-case and we welcome help with testing +and development. @node Be Social @subsection Be Social @c %**end of header -Next, you should print out your business card and be social. Find a friend, help -him install GNUnet and exchange business cards with him. Or, if you're a -desperate loner, you might try the next step with your own card. Still, it'll be -hard to have a conversation with yourself later, so it would be better if you -could find a friend. You might also want a camera attached to your computer, so -you might need a trip to the store together. Once you have a business card, run: +Next, you should print out your business card and be social. +Find a friend, help them install GNUnet and exchange business cards with +them. Or, if you're a desperate loner, you might try the next step with +your own card. Still, it'll be hard to have a conversation with +yourself later, so it would be better if you could find a friend. +You might also want a camera attached to your computer, so +you might need a trip to the store together. Once you have a +business card, run: @example $ gnunet-qr @end example -to open a window showing whatever your camera points at. Hold up your friend's -business card and tilt it until the QR code is recognized. At that point, the -window should automatically close. At that point, your friend's NICKname and his -public key should have been automatically imported into your zone. Assuming both -of your peers are properly integrated in the GNUnet network at this time, you -should thus be able to resolve your friends names. Suppose your friend's -nickname is "Bob". Then, type +@noindent +to open a window showing whatever your camera points at. +Hold up your friend's business card and tilt it until +the QR code is recognized. At that point, the window should +automatically close. At that point, your friend's NICKname and their +public key should have been automatically imported into your zone. +Assuming both of your peers are properly integrated in the +GNUnet network at this time, you should thus be able to +resolve your friends names. Suppose your friend's nickname +is "Bob". Then, type @example $ gnunet-gns -u test.bob.gnu @end example -to check if your friend was as good at following instructions as you were. +@noindent +to check if your friend was as good at following instructions +as you were. @node Backup of Identities and Egos @@ -475,55 +526,60 @@ The peer identity file can be found in @file{~/.local/share/gnunet/private_key.ecc} The private keys of your egos are stored in the -directory @file{~/.local/share/gnunet/identity/egos/}. They are stored in -files whose filenames correspond to the zones' ego names. These are -probably the most important files you want to backup from a GNUnet -installation. +directory @file{~/.local/share/gnunet/identity/egos/}. +They are stored in files whose filenames correspond to the zones' +ego names. These are probably the most important files you want +to backup from a GNUnet installation. -Note: All these files contain cryptographic keys and they are stored without -any encryption. So it is advisable to backup encrypted copies of them. +Note: All these files contain cryptographic keys and they are +stored without any encryption. So it is advisable to backup +encrypted copies of them. @node Revocation @subsection Revocation Now, in the situation of an attacker gaining access to the private key of -one of your egos, the attacker can create records in the respective GNS zone -and publish them as if you published them. Anyone resolving your domain will -get these new records and when they verify they seem authentic because the -attacker has signed them with your key. - -To address this potential security issue, you can pre-compute a revocation -certificate corresponding to your ego. This certificate, when published on -the P2P network, flags your private key as invalid, and all further -resolutions or other checks involving the key will fail. - -A revocation certificate is thus a useful tool when things go out of control, -but at the same time it should be stored securely. Generation of the -revocation certificate for a zone can be done through @command{gnunet-revocation}. -For example, the following command (as unprivileged user) generates a revocation -file @file{revocation.dat} for the zone @code{zone1}: +one of your egos, the attacker can create records in the respective +GNS zone +and publish them as if you published them. Anyone resolving your +domain will get these new records and when they verify they seem +authentic because the attacker has signed them with your key. + +To address this potential security issue, you can pre-compute +a revocation certificate corresponding to your ego. This certificate, +when published on the P2P network, flags your private key as invalid, +and all further resolutions or other checks involving the key will fail. + +A revocation certificate is thus a useful tool when things go out of +control, but at the same time it should be stored securely. +Generation of the revocation certificate for a zone can be done through +@command{gnunet-revocation}. For example, the following command (as +unprivileged user) generates a revocation file +@file{revocation.dat} for the zone @code{zone1}: @command{gnunet-revocation -f revocation.dat -R zone1} -The above command only pre-computes a revocation certificate. It does not -revoke the given zone. Pre-computing a revocation certificate involves -computing a proof-of-work and hence may take upto 4 to 5 days on a modern -processor. Note that you can abort and resume the calculation at any time. -Also, even if you did not finish the calculation, the resulting file willl -contain the signature, which is sufficient to complete the revocation -process even without access to the private key. So instead of waiting for a -few days, you can just abort with CTRL-C, backup the revocation -certificate and run the calculation only if your key actually was compromised. -This has the disadvantage of revocation taking longer after the incident, but -the advantage of saving a significant amount of energy. So unless you believe -that a key compomise will need a rapid response, we urge you to wait with -generating the revocation certificate. Also, the calculation is deliberately -expensive, to deter people from doing this just for fun (as the actual -revocation operation is expensive for the network, not for the peer performing -the revocation). - -To avoid TL;DR ones from accidentally revocating their zones, I am not giving -away the command, but its simple: the actual revocation is performed by using -the @command{-p} option of @command{gnunet-revocation}. +The above command only pre-computes a revocation certificate. It does +not revoke the given zone. Pre-computing a revocation certificate +involves computing a proof-of-work and hence may take upto 4 to 5 days +on a modern processor. Note that you can abort and resume the +calculation at any time. Also, even if you did not finish the +calculation, the resulting file will contain the signature, which is +sufficient to complete the revocation process even without access to +the private key. So instead of waiting for a few days, you can just +abort with CTRL-C, backup the revocation certificate and run the +calculation only if your key actually was compromised. This has the +disadvantage of revocation taking longer after the incident, but +the advantage of saving a significant amount of energy. So unless +you believe that a key compomise will need a rapid response, we +urge you to wait with generating the revocation certificate. +Also, the calculation is deliberately expensive, to deter people from +doing this just for fun (as the actual revocation operation is expensive +for the network, not for the peer performing the revocation). + +To avoid TL;DR ones from accidentally revocating their zones, I am not +giving away the command, but its simple: the actual revocation is +performed by using the @command{-p} option +of @command{gnunet-revocation}. @@ -531,27 +587,31 @@ the @command{-p} option of @command{gnunet-revocation}. @subsection What's Next? @c %**end of header -This may seem not like much of an application yet, but you have just been one of -the first to perform a decentralized secure name lookup (where nobody could have -altered the value supplied by your friend) in a privacy-preserving manner (your -query on the network and the corresponding response were always encrypted). So -what can you really do with this? Well, to start with, you can publish your -GnuPG fingerprint in GNS as a "CERT" record and replace the public web-of-trust -with its complicated trust model with explicit names and privacy-preserving -resolution. Also, you should read the next chapter of the tutorial and learn how -to use GNS to have a private conversation with your friend. Finally, help us -with the next GNUnet release for even more applications using this new -public key infrastructure. +This may seem not like much of an application yet, but you have +just been one of the first to perform a decentralized secure name +lookup (where nobody could have altered the value supplied by your +friend) in a privacy-preserving manner (your query on the network +and the corresponding response were always encrypted). So what +can you really do with this? Well, to start with, you can publish your +GnuPG fingerprint in GNS as a "CERT" record and replace the public +web-of-trust with its complicated trust model with explicit names +and privacy-preserving resolution. Also, you should read the next +chapter of the tutorial and learn how to use GNS to have a +private conversation with your friend. Finally, help us +with the next GNUnet release for even more applications +using this new public key infrastructure. @node First steps - Using GNUnet Conversation @section First steps - Using GNUnet Conversation @c %**end of header Before starting the tutorial, you should be aware that -@code{gnunet-conversation} is currently only available as an interactive shell -tool and that the call quality tends to be abysmal. There are also some awkward -steps necessary to use it. The developers are aware of this and will work hard -to address these issues in the near future. +@code{gnunet-conversation} is currently only available +as an interactive shell tool and that the call quality +tends to be abysmal. There are also some awkward +steps necessary to use it. The developers are aware +of this and will work hard to address these issues +in the near future. @menu @@ -565,20 +625,20 @@ to address these issues in the near future. @c %**end of header First, you should use @code{gnunet-conversation-test} to check that your -microphone and speaker are working correctly. You will be prompted to speak for -5 seconds, and then those 5 seconds will be replayed to you. The network is not -involved in this test. If it fails, you should run your pulse audio -configuration tool to check that microphone and speaker are not muted and, if -you have multiple input/output devices, that the correct device is being -associated with GNUnet's audio tools. +microphone and speaker are working correctly. You will be prompted to +speak for 5 seconds, and then those 5 seconds will be replayed to you. +The network is not involved in this test. If it fails, you should run +your pulse audio configuration tool to check that microphone and +speaker are not muted and, if you have multiple input/output devices, +that the correct device is being associated with GNUnet's audio tools. @node GNS Zones @subsection GNS Zones @c %**end of header -@code{gnunet-conversation} uses GNS for addressing. This means that you need to -have a GNS zone created before using it. Information about how to create GNS -zones can be found here. +@code{gnunet-conversation} uses GNS for addressing. This means that +you need to have a GNS zone created before using it. Information +about how to create GNS zones can be found here. @menu @@ -590,71 +650,83 @@ zones can be found here. @subsubsection Picking an Identity @c %**end of header -To make a call with @code{gnunet-conversation}, you first need to choose an -identity. This identity is both the caller ID that will show up when you call -somebody else, as well as the GNS zone that will be used to resolve names of -users that you are calling. Usually, the @code{master-zone} is a reasonable +To make a call with @code{gnunet-conversation}, you first +need to choose an identity. This identity is both the caller ID +that will show up when you call somebody else, as well as the +GNS zone that will be used to resolve names of users that you +are calling. Usually, the @code{master-zone} is a reasonable choice. Run @example gnunet-conversation -e master-zone @end example -to start the command-line tool. You will see a message saying that your phone is -now "active on line 0". You can connect multiple phones on different lines at -the same peer. For the first phone, the line zero is of course a fine choice. +@noindent +to start the command-line tool. You will see a message saying +that your phone is now "active on line 0". You can connect +multiple phones on different lines at the same peer. For the +first phone, the line zero is of course a fine choice. -Next, you should type in @command{/help} for a list of available commands. We will -explain the important ones during this tutorial. First, you will need to type in -@command{/address} to determine the address of your phone. The result should look -something like this: +Next, you should type in @command{/help} for a list of +available commands. We will explain the important ones +during this tutorial. First, you will need to type in +@command{/address} to determine the address of your +phone. The result should look something like this: @example /address 0-PD67SGHF3E0447TU9HADIVU9OM7V4QHTOG0EBU69TFRI2LG63DR0 @end example -Here, the "0" is your phone line, and what follows after the hyphen is your -peer's identity. This information will need to be placed in a PHONE record of +@noindent +Here, the "0" is your phone line, and what follows +after the hyphen is your peer's identity. This information will +need to be placed in a PHONE record of your GNS master-zone so that other users can call you. -Start @code{gnunet-namestore-gtk} now (possibly from another shell) and create -an entry home-phone in your master zone. For the record type, select PHONE. You -should then see the PHONE dialog:@ +Start @code{gnunet-namestore-gtk} now (possibly from another +shell) and create an entry home-phone in your master zone. +For the record type, select PHONE. You should then see the +PHONE dialog: -Note: Do not choose the expiry time to be 'Never'. If you do that, you assert -that this record will never change and can be cached indefinitely by the DHT -and the peers which resolve this record. A reasonable period is 1 year. +@c image here -Enter your peer identity under Peer and leave the line at zero. Select the first -option to make the record public. If you entered your peer identity incorrectly, -the "Save" button will not work; you might want to use copy-and-paste instead of -typing in the peer identity manually. Save the record. +Note: Do not choose the expiry time to be 'Never'. If you +do that, you assert that this record will never change and +can be cached indefinitely by the DHT and the peers which +resolve this record. A reasonable period is 1 year. + +Enter your peer identity under Peer and leave the line +at zero. Select the first option to make the record public. +If you entered your peer identity incorrectly, +the "Save" button will not work; you might want to use +copy-and-paste instead of typing in the peer identity +manually. Save the record. @node Calling somebody @subsubsection Calling somebody @c %**end of header Now you can call a buddy. Obviously, your buddy will have to have GNUnet -installed and must have performed the same steps. Also, you must have your buddy -in your GNS master zone, for example by having imported your buddy's public key -using @code{gnunet-qr}. Suppose your buddy is in your zone as @code{buddy.gnu} -and he also created his phone using a label "home-phone". Then you can initiate -a call using: +installed and must have performed the same steps. Also, you must have +your buddy in your GNS master zone, for example by having imported +your buddy's public key using @code{gnunet-qr}. Suppose your buddy +is in your zone as @code{buddy.gnu} and they also created their +phone using a label "home-phone". Then you can initiate a call using: @example /call home-phone.buddy.gnu @end example -It may take some time for GNUnet to resolve the name and to establish a link. If -your buddy has your public key in his master zone, he should see an incoming -call with your name. If your public key is not in his master zone, he will just -see the public key as the caller ID. +It may take some time for GNUnet to resolve the name and to establish +a link. If your buddy has your public key in their master zone, they +should see an incoming call with your name. If your public key is not +in their master zone, they will just see the public key as the caller ID. Your buddy then can answer the call using the "/accept" command. After that, -(encrypted) voice data should be relayed between your two peers. Either of you -can end the call using @command{/cancel}. You can exit @code{gnunet-converation} using -@command{/quit}. +(encrypted) voice data should be relayed between your two peers. +Either of you can end the call using @command{/cancel}. You can exit +@code{gnunet-converation} using @command{/quit}. @node Future Directions @subsection Future Directions @@ -681,32 +753,38 @@ automatically create the necessary records in the respective zone. @subsection VPN Preliminaries @c %**end of header -To test the GNUnet VPN, we should first run a web server. The easiest way to do -this is to just start @code{gnunet-bcd}, which will run a webserver on port -@code{8888} by default. Naturally, you can run some other HTTP server for our -little tutorial. +To test the GNUnet VPN, we should first run a web server. +The easiest way to do this is to just start @code{gnunet-bcd}, +which will run a webserver on port @code{8888} by default. +Naturally, you can run some other HTTP server for our little tutorial. + +If you have not done this, you should also configure your +Name System Service switch to use GNS. In your @code{/etc/nsswitch.conf} +you should fine a line like this: -If you have not done this, you should also configure your Name System Service -switch to use GNS. In your @code{/etc/nsswitch.conf} you should fine a line like -this: @example hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4 @end example +@noindent The exact details may differ a bit, which is fine. Add the text @code{gns [NOTFOUND=return]} after @code{files}: + @example hosts: files gns [NOTFOUND=return] mdns4_minimal [NOTFOUND=return] dns mdns4 @end example +@noindent +You might want to make sure that @code{/lib/libnss_gns.so.2} exists on +your system, it should have been created during the installation. +If not, re-run -You might want to make sure that @code{/lib/libnss_gns.so.2} exists on your -system, it should have been created during the installation. If not, re-run @example $ configure --with-nssdir=/lib $ cd src/gns/nss; sudo make install @end example +@noindent to install the NSS plugins in the proper location. @node Exit configuration @@ -715,12 +793,12 @@ to install the NSS plugins in the proper location. Stop your peer (as user @code{gnunet}, run @code{gnunet-arm -e}) and run @code{gnunet-setup}. In @code{gnunet-setup}, make sure to activate the -@strong{EXIT} and @strong{GNS} services in the General tab. Then select the Exit -tab. Most of the defaults should be fine (but you should check against the -screenshot that they have not been modified). In the bottom area, enter -@code{bcd} under Identifier and change the Destination to -@code{169.254.86.1:8888} (if your server runs on a port other than 8888, change -the 8888 port accordingly). +@strong{EXIT} and @strong{GNS} services in the General tab. Then select +the Exit tab. Most of the defaults should be fine (but you should check +against the screenshot that they have not been modified). In the +bottom area, enter @code{bcd} under Identifier and change the +Destination to @code{169.254.86.1:8888} (if your server runs on a port +other than 8888, change the 8888 port accordingly). Now exit @code{gnunet-setup} and restart your peer (@code{gnunet-arm -s}). @@ -729,49 +807,54 @@ Now exit @code{gnunet-setup} and restart your peer (@code{gnunet-arm -s}). @c %**end of header Now, using your normal user (not the @code{gnunet} system user), run -@code{gnunet-gtk}. Select the GNS icon and add a new label www in your master -zone. For the record type, select @code{VPN}. You should then see the VPN -dialog: +@code{gnunet-gtk}. Select the GNS icon and add a new label www in your +master zone. For the record type, select @code{VPN}. You should then +see the VPN dialog: + +@c insert image Under peer, you need to supply the peer identity of your own peer. You can -obtain the respective string by running@ -@code{@ - $ gnunet-peerinfo -sq@ -}@ +obtain the respective string by running @code{ $ gnunet-peerinfo -sq} as the @code{gnunet} user. For the Identifier, you need to supply the same -identifier that we used in the Exit setup earlier, so here supply "bcd". If you -want others to be able to use the service, you should probably make the record -public. For non-public services, you should use a passphrase instead of the -string "bcd". Save the record and exit @code{gnunet-gtk}. +identifier that we used in the Exit setup earlier, so here supply "bcd". +If you want others to be able to use the service, you should probably make +the record public. For non-public services, you should use a passphrase +instead of the string "bcd". Save the record and exit @code{gnunet-gtk}. @node Accessing the service @subsection Accessing the service @c %**end of header -You should now be able to access your webserver. Type in:@ -@code{@ - $ wget http://www.gnu/@ -}@ -The request will resolve to the VPN record, telling the GNS resolver to route it -via the GNUnet VPN. The GNS resolver will ask the GNUnet VPN for an IPv4 address -to return to the application. The VPN service will use the VPN information -supplied by GNS to create a tunnel (via GNUnet's MESH service) to the EXIT peer. -At the EXIT, the name "bcd" and destination port (80) will be mapped to the -specified destination IP and port. While all this is currently happening on just -the local machine, it should also work with other peers --- naturally, they will -need a way to access your GNS zone first, for example by learning your public -key from a QR code on your business card. +You should now be able to access your webserver. Type in: + +@example +$ wget http://www.gnu/ +@end example + +@noindent +The request will resolve to the VPN record, telling the GNS resolver +to route it via the GNUnet VPN. The GNS resolver will ask the +GNUnet VPN for an IPv4 address to return to the application. The +VPN service will use the VPN information supplied by GNS to create +a tunnel (via GNUnet's MESH service) to the EXIT peer. +At the EXIT, the name "bcd" and destination port (80) will be mapped +to the specified destination IP and port. While all this is currently +happening on just the local machine, it should also work with other +peers --- naturally, they will need a way to access your GNS zone +first, for example by learning your public key from a QR code on +your business card. @node Using a Browser @subsection Using a Browser @c %**end of header -Sadly, modern browsers tend to bypass the Name Services Switch and attempt DNS -resolution directly. You can either run a @code{gnunet-dns2gns} DNS proxy, or -point the browsers to an HTTP proxy. When we tried it, Iceweasel did not like to -connect to the socks proxy for @code{.gnu} TLDs, even if we disabled its -autoblunder of changing @code{.gnu} to ".gnu.com". Still, using the HTTP proxy -with Chrome does work. +Sadly, modern browsers tend to bypass the Name Services Switch and +attempt DNS resolution directly. You can either run +a @code{gnunet-dns2gns} DNS proxy, or point the browsers to an +HTTP proxy. When we tried it, Iceweasel did not like to connect to +the socks proxy for @code{.gnu} TLDs, even if we disabled its +autoblunder of changing @code{.gnu} to ".gnu.com". Still, +using the HTTP proxy with Chrome does work. @node File-sharing @section File-sharing @@ -779,19 +862,20 @@ with Chrome does work. This chapter documents the GNUnet file-sharing application. The original file-sharing implementation for GNUnet was designed to provide -@strong{anonymous} file-sharing. However, over time, we have also added support -for non-anonymous file-sharing (which can provide better performance). Anonymous -and non-anonymous file-sharing are quite integrated in GNUnet and, except for -routing, share most of the concepts and implementation. There are three primary -file-sharing operations: publishing, searching and downloading. For each of -these operations, the user specifies an @strong{anonymity level}. If both the -publisher and the searcher/downloader specify "no anonymity", non-anonymous -file-sharing is used. If either user specifies some desired degree of anonymity, -anonymous file-sharing will be used. +@strong{anonymous} file-sharing. However, over time, we have also added +support for non-anonymous file-sharing (which can provide better +performance). Anonymous and non-anonymous file-sharing are quite +integrated in GNUnet and, except for routing, share most of the concepts +and implementation. There are three primary file-sharing operations: +publishing, searching and downloading. For each of these operations, +the user specifies an @strong{anonymity level}. If both the publisher and +the searcher/downloader specify "no anonymity", non-anonymous +file-sharing is used. If either user specifies some desired degree +of anonymity, anonymous file-sharing will be used. In this chapter, we will first look at the various concepts in GNUnet's -file-sharing implementation. Then, we will discuss specifics as to how they -impact users that publish, search or download files. +file-sharing implementation. Then, we will discuss specifics as to +how they impact users that publish, search or download files. @@ -809,17 +893,18 @@ impact users that publish, search or download files. @subsection File-sharing Concepts @c %**end of header -Sharing files in GNUnet is not quite as simple as in traditional file sharing -systems. For example, it is not sufficient to just place files into a specific -directory to share them. In addition to anonymous routing GNUnet attempts to -give users a better experience in searching for content. GNUnet uses -cryptography to safely break content into smaller pieces that can be obtained -from different sources without allowing participants to corrupt files. GNUnet -makes it difficult for an adversary to send back bogus search results. GNUnet -enables content providers to group related content and to establish a -reputation. Furthermore, GNUnet allows updates to certain content to be made -available. This section is supposed to introduce users to the concepts that are -used to achive these goals. +Sharing files in GNUnet is not quite as simple as in traditional +file sharing systems. For example, it is not sufficient to just +place files into a specific directory to share them. In addition +to anonymous routing GNUnet attempts to give users a better experience +in searching for content. GNUnet uses cryptography to safely break +content into smaller pieces that can be obtained from different +sources without allowing participants to corrupt files. GNUnet +makes it difficult for an adversary to send back bogus search +results. GNUnet enables content providers to group related content +and to establish a reputation. Furthermore, GNUnet allows updates +to certain content to be made available. This section is supposed +to introduce users to the concepts that are used to achive these goals. @menu @@ -838,83 +923,86 @@ used to achive these goals. @subsubsection Files @c %**end of header -A file in GNUnet is just a sequence of bytes. Any file-format is allowed and the -maximum file size is theoretically 264 bytes, except that it would take an -impractical amount of time to share such a file. GNUnet itself never interprets -the contents of shared files, except when using GNU libextractor to obtain -keywords. +A file in GNUnet is just a sequence of bytes. Any file-format is allowed +and the maximum file size is theoretically 264 bytes, except that it +would take an impractical amount of time to share such a file. +GNUnet itself never interprets the contents of shared files, except +when using GNU libextractor to obtain keywords. @node Keywords @subsubsection Keywords @c %**end of header -Keywords are the most simple mechanism to find files on GNUnet. Keywords are -@strong{case-sensitive} and the search string must always match @strong{exactly} -the keyword used by the person providing the file. Keywords are never -transmitted in plaintext. The only way for an adversary to determine the keyword -that you used to search is to guess it (which then allows the adversary to -produce the same search request). Since providing keywords by hand for each -shared file is tedious, GNUnet uses GNU libextractor to help automate this -process. Starting a keyword search on a slow machine can take a little while -since the keyword search involves computing a fresh RSA key to formulate the +Keywords are the most simple mechanism to find files on GNUnet. +Keywords are @strong{case-sensitive} and the search string +must always match @strong{exactly} the keyword used by the +person providing the file. Keywords are never transmitted in +plaintext. The only way for an adversary to determine the keyword +that you used to search is to guess it (which then allows the +adversary to produce the same search request). Since providing +keywords by hand for each shared file is tedious, GNUnet uses +GNU libextractor to help automate this process. Starting a +keyword search on a slow machine can take a little while since +the keyword search involves computing a fresh RSA key to formulate the request. @node Directories @subsubsection Directories @c %**end of header -A directory in GNUnet is a list of file identifiers with meta data. The file -identifiers provide sufficient information about the files to allow downloading -the contents. Once a directory has been created, it cannot be changed since it -is treated just like an ordinary file by the network. Small files (of a few -kilobytes) can be inlined in the directory, so that a separate download becomes -unnecessary. +A directory in GNUnet is a list of file identifiers with meta data. +The file identifiers provide sufficient information about the files +to allow downloading the contents. Once a directory has been created, +it cannot be changed since it is treated just like an ordinary file +by the network. Small files (of a few kilobytes) can be inlined in +the directory, so that a separate download becomes unnecessary. @node Pseudonyms @subsubsection Pseudonyms @c %**end of header -Pseudonyms in GNUnet are essentially public-private (RSA) key pairs that allow a -GNUnet user to maintain an identity (which may or may not be detached from his -real-life identity). GNUnet's pseudonyms are not file-sharing specific --- and -they will likely be used by many GNUnet applications where a user identity is -required. +Pseudonyms in GNUnet are essentially public-private (RSA) key pairs +that allow a GNUnet user to maintain an identity (which may or may not +be detached from their real-life identity). GNUnet's pseudonyms are not +file-sharing specific --- and they will likely be used by many GNUnet +applications where a user identity is required. Note that a pseudonym is NOT bound to a GNUnet peer. There can be multiple -pseudonyms for a single user, and users could (theoretically) share the private -pseudonym keys (currently only out-of-band by knowing which files to copy -around). +pseudonyms for a single user, and users could (theoretically) share the +private pseudonym keys (currently only out-of-band by knowing which files +to copy around). @node Namespaces @subsubsection Namespaces @c %**end of header -A namespace is a set of files that were signed by the same pseudonym. Files (or -directories) that have been signed and placed into a namespace can be updated. -Updates are identified as authentic if the same secret key was used to sign the -update. Namespaces are also useful to establish a reputation, since all of the -content in the namespace comes from the same entity (which does not have to be -the same person). +A namespace is a set of files that were signed by the same pseudonym. +Files (or directories) that have been signed and placed into a namespace +can be updated. Updates are identified as authentic if the same secret +key was used to sign the update. Namespaces are also useful to establish +a reputation, since all of the content in the namespace comes from the +same entity (which does not have to be the same person). @node Advertisements @subsubsection Advertisements @c %**end of header Advertisements are used to notify other users about the existence of a -namespace. Advertisements are propagated using the normal keyword search. When -an advertisement is received (in response to a search), the namespace is added -to the list of namespaces available in the namespace-search dialogs of -gnunet-fs-gtk and printed by gnunet-pseudonym. Whenever a namespace is created, -an appropriate advertisement can be generated. The default keyword for the -advertising of namespaces is "namespace". - -Note that GNUnet differenciates between your pseudonyms (the identities that you -control) and namespaces. If you create a pseudonym, you will not automatically -see the respective namespace. You first have to create an advertisement for the -namespace and find it using keyword search --- even for your own namespaces. The -@code{gnunet-pseudonym} tool is currently responsible for both managing -pseudonyms and namespaces. This will likely change in the future to reduce the -potential for confusion. +namespace. Advertisements are propagated using the normal keyword search. +When an advertisement is received (in response to a search), the namespace +is added to the list of namespaces available in the namespace-search +dialogs of gnunet-fs-gtk and printed by gnunet-pseudonym. Whenever a +namespace is created, an appropriate advertisement can be generated. +The default keyword for the advertising of namespaces is "namespace". + +Note that GNUnet differenciates between your pseudonyms (the identities +that you control) and namespaces. If you create a pseudonym, you will +not automatically see the respective namespace. You first have to create +an advertisement for the namespace and find it using keyword +search --- even for your own namespaces. The @code{gnunet-pseudonym} +tool is currently responsible for both managing pseudonyms and namespaces. +This will likely change in the future to reduce the potential for +confusion. @node Anonymity level @subsubsection Anonymity level @@ -924,44 +1012,47 @@ The anonymity level determines how hard it should be for an adversary to determine the identity of the publisher or the searcher/downloader. An anonymity level of zero means that anonymity is not required. The default anonymity level of "1" means that anonymous routing is desired, but no -particular amount of cover traffic is necessary. A powerful adversary might thus -still be able to deduce the origin of the traffic using traffic analysis. -Specifying higher anonymity levels increases the amount of cover traffic -required. While this offers better privacy, it can also significantly hurt -performance. +particular amount of cover traffic is necessary. A powerful adversary +might thus still be able to deduce the origin of the traffic using +traffic analysis. Specifying higher anonymity levels increases the +amount of cover traffic required. While this offers better privacy, +it can also significantly hurt performance. @node Content Priority @subsubsection Content Priority @c %**end of header -Depending on the peer's configuration, GNUnet peers migrate content between -peers. Content in this sense are individual blocks of a file, not necessarily -entire files. When peers run out of space (due to local publishing operations or -due to migration of content from other peers), blocks sometimes need to be -discarded. GNUnet first always discards expired blocks (typically, blocks are -published with an expiration of about two years in the future; this is another -option). If there is still not enough space, GNUnet discards the blocks with the -lowest priority. The priority of a block is decided by its popularity (in terms -of requests from peers we trust) and, in case of blocks published locally, the -base-priority that was specified by the user when the block was published -initially. +Depending on the peer's configuration, GNUnet peers migrate content +between peers. Content in this sense are individual blocks of a file, +not necessarily entire files. When peers run out of space (due to +local publishing operations or due to migration of content from other +peers), blocks sometimes need to be discarded. GNUnet first always +discards expired blocks (typically, blocks are published with an +expiration of about two years in the future; this is another option). +If there is still not enough space, GNUnet discards the blocks with the +lowest priority. The priority of a block is decided by its popularity +(in terms of requests from peers we trust) and, in case of blocks +published locally, the base-priority that was specified by the user +when the block was published initially. @node Replication @subsubsection Replication @c %**end of header -When peers migrate content to other systems, the replication level of a block is -used to decide which blocks need to be migrated most urgently. GNUnet will -always push the block with the highest replication level into the network, and -then decrement the replication level by one. If all blocks reach replication -level zero, the selection is simply random. +When peers migrate content to other systems, the replication level +of a block is used to decide which blocks need to be migrated most +urgently. GNUnet will always push the block with the highest +replication level into the network, and then decrement the replication +level by one. If all blocks reach replication level zero, the +selection is simply random. @node File-sharing Publishing @subsection File-sharing Publishing @c %**end of header -The command @code{gnunet-publish} can be used to add content to the network. -The basic format of the command is +The command @code{gnunet-publish} can be used to add content +to the network. The basic format of the command is + @example $ gnunet-publish [-n] [-k KEYWORDS]* [-m TYPE:VALUE] FILENAME @end example @@ -976,102 +1067,114 @@ $ gnunet-publish [-n] [-k KEYWORDS]* [-m TYPE:VALUE] FILENAME @subsubsection Important command-line options @c %**end of header -The option -k is used to specify keywords for the file that should be inserted. -You can supply any number of keywords, and each of the keywords will be -sufficient to locate and retrieve the file. +The option -k is used to specify keywords for the file that +should be inserted. You can supply any number of keywords, +and each of the keywords will be sufficient to locate and +retrieve the file. -The -m option is used to specify meta-data, such as descriptions. You can use -m -multiple times. The TYPE passed must be from the list of meta-data types known -to libextractor. You can obtain this list by running @code{extract -L}. -Use quotes around the entire meta-data argument if the value contains spaces. -The meta-data is displayed to other users when they select which files to -download. The meta-data and the keywords are optional and maybe inferred using -@code{GNU libextractor}. +The -m option is used to specify meta-data, such as descriptions. +You can use -m multiple times. The TYPE passed must be from the +list of meta-data types known to libextractor. You can obtain this +list by running @code{extract -L}. Use quotes around the entire +meta-data argument if the value contains spaces. The meta-data +is displayed to other users when they select which files to +download. The meta-data and the keywords are optional and +maybe inferred using @code{GNU libextractor}. gnunet-publish has a few additional options to handle namespaces and -directories. -See the man-page for details. +directories. See the man-page for details. @node Indexing vs. Inserting @subsubsection Indexing vs Inserting @c %**end of header -By default, GNUnet indexes a file instead of making a full copy. This is much -more efficient, but requries the file to stay unaltered at the location where it -was when it was indexed. If you intend to move, delete or alter a file, consider -using the option @code{-n} which will force GNUnet to make a copy of the file in -the database. - -Since it is much less efficient, this is strongly discouraged for large files. -When GNUnet indexes a file (default), GNUnet does @strong{not} create an -additional encrypted copy of the file but just computes a summary (or index) of -the file. That summary is approximately two percent of the size of the original -file and is stored in GNUnet's database. Whenever a request for a part of an -indexed file reaches GNUnet, this part is encrypted on-demand and send out. This -way, there is no need for an additional encrypted copy of the file to stay -anywhere on the drive. This is different from other systems, such as Freenet, -where each file that is put online must be in Freenet's database in encrypted -format, doubling the space requirements if the user wants to preseve a directly -accessible copy in plaintext. - -Thus indexing should be used for all files where the user will keep using this -file (at the location given to gnunet-publish) and does not want to retrieve it -back from GNUnet each time. If you want to remove a file that you have indexed -from the local peer, use the tool @code{gnunet-unindex} to un-index the file. - -The option @code{-n} may be used if the user fears that the file might be found -on his drive (assuming the computer comes under the control of an adversary). -When used with the @code{-n} flag, the user has a much better chance of denying -knowledge of the existence of the file, even if it is still (encrypted) on the -drive and the adversary is able to crack the encryption (e.g. by guessing the -keyword. +By default, GNUnet indexes a file instead of making a full copy. +This is much more efficient, but requries the file to stay unaltered +at the location where it was when it was indexed. If you intend to move, +delete or alter a file, consider using the option @code{-n} which will +force GNUnet to make a copy of the file in the database. + +Since it is much less efficient, this is strongly discouraged for large +files. When GNUnet indexes a file (default), GNUnet does @strong{not} +create an additional encrypted copy of the file but just computes a +summary (or index) of the file. That summary is approximately two percent +of the size of the original file and is stored in GNUnet's database. +Whenever a request for a part of an indexed file reaches GNUnet, +this part is encrypted on-demand and send out. This way, there is no +need for an additional encrypted copy of the file to stay anywhere +on the drive. This is different from other systems, such as Freenet, +where each file that is put online must be in Freenet's database in +encrypted format, doubling the space requirements if the user wants +to preseve a directly accessible copy in plaintext. + +Thus indexing should be used for all files where the user will keep +using this file (at the location given to gnunet-publish) and does +not want to retrieve it back from GNUnet each time. If you want to +remove a file that you have indexed from the local peer, use the tool +@code{gnunet-unindex} to un-index the file. + +The option @code{-n} may be used if the user fears that the file might +be found on their drive (assuming the computer comes under the control +of an adversary). When used with the @code{-n} flag, the user has a +much better chance of denying knowledge of the existence of the file, +even if it is still (encrypted) on the drive and the adversary is +able to crack the encryption (e.g. by guessing the keyword. @node File-sharing Searching @subsection File-sharing Searching @c %**end of header -The command @code{gnunet-search} can be used to search for content on GNUnet. -The format is: +The command @code{gnunet-search} can be used to search +for content on GNUnet. The format is: + @example $ gnunet-search [-t TIMEOUT] KEYWORD @end example -The -t option specifies that the query should timeout after approximately -TIMEOUT seconds. A value of zero is interpreted as @emph{no timeout}, which is -also the default. In this case, gnunet-search will never terminate (unless you -press CTRL-C). +@noindent +The -t option specifies that the query should timeout after +approximately TIMEOUT seconds. A value of zero is interpreted +as @emph{no timeout}, which is also the default. In this case, +gnunet-search will never terminate (unless you press CTRL-C). -If multiple words are passed as keywords, they will all be considered optional. -Prefix keywords with a "+" to make them mandatory. +If multiple words are passed as keywords, they will all be +considered optional. Prefix keywords with a "+" to make them mandatory. Note that searching using + @example $ gnunet-search Das Kapital @end example +@noindent is not the same as searching for + @example $ gnunet-search "Das Kapital" @end example -as the first will match files shared under the keywords "Das" or "Kapital" -whereas the second will match files shared under the keyword "Das Kapital". +@noindent +as the first will match files shared under the keywords +"Das" or "Kapital" whereas the second will match files +shared under the keyword "Das Kapital". Search results are printed by gnunet-search like this: + @example $ gnunet-download -o "COPYING" --- gnunet://fs/chk/N8...C92.17992 => The GNU Public License <= (mimetype: text/plain) @end example -The first line is the command you would have to enter to download the file. -The argument passed to @code{-o} is the suggested filename (you may change it to -whatever you like). -The @code{--} is followed by key for decrypting the file, the query for -searching the file, a checksum (in hexadecimal) finally the size of the file in -bytes. +@noindent +The first line is the command you would have to enter to download +the file. The argument passed to @code{-o} is the suggested +filename (you may change it to whatever you like). +The @code{--} is followed by key for decrypting the file, +the query for searching the file, a checksum (in hexadecimal) +finally the size of the file in bytes. The second line contains the description of the file; here this is -"The GNU Public License" and the mime-type (see the options for gnunet-publish -on how to specify these). +"The GNU Public License" and the mime-type (see the options for +gnunet-publish on how to specify these). @node File-sharing Downloading @subsection File-sharing Downloading @@ -1080,54 +1183,65 @@ on how to specify these). In order to download a file, you need the three values returned by @code{gnunet-search}. You can then use the tool @code{gnunet-download} to obtain the file: + @example $ gnunet-download -o FILENAME --- GNUNETURL @end example -FILENAME specifies the name of the file where GNUnet is supposed to write the -result. Existing files are overwritten. If the existing file contains blocks -that are identical to the desired download, those blocks will not be downloaded -again (automatic resume). +@noindent +FILENAME specifies the name of the file where GNUnet is supposed +to write the result. Existing files are overwritten. If the +existing file contains blocks that are identical to the +desired download, those blocks will not be downloaded again +(automatic resume). + +If you want to download the GPL from the previous example, +you do the following: -If you want to download the GPL from the previous example, you do the following: @example $ gnunet-download -o "COPYING" --- gnunet://fs/chk/N8...92.17992 @end example +@noindent If you ever have to abort a download, you can continue it at any time by -re-issuing @command{gnunet-download} with the same filename. In that case, GNUnet -will @strong{not} download blocks again that are already present. +re-issuing @command{gnunet-download} with the same filename. +In that case, GNUnet will @strong{not} download blocks again that are +already present. GNUnet's file-encoding mechanism will ensure file integrity, even if the existing file was not downloaded from GNUnet in the first place. -You may want to use the @command{-V} switch (must be added before the @command{--}) to -turn on verbose reporting. In this case, @command{gnunet-download} will print the -current number of bytes downloaded whenever new data was received. +You may want to use the @command{-V} switch (must be added before +the @command{--}) to turn on verbose reporting. In this case, +@command{gnunet-download} will print the current number of +bytes downloaded whenever new data was received. @node File-sharing Directories @subsection File-sharing Directories @c %**end of header -Directories are shared just like ordinary files. If you download a directory -with @command{gnunet-download}, you can use @command{gnunet-directory} to list its -contents. The canonical extension for GNUnet directories when stored as files in -your local file-system is ".gnd". The contents of a directory are URIs and +Directories are shared just like ordinary files. If you download a +directory with @command{gnunet-download}, you can use +@command{gnunet-directory} to list its contents. The canonical +extension for GNUnet directories when stored as files in your +local file-system is ".gnd". The contents of a directory are URIs and meta data. -The URIs contain all the information required by @command{gnunet-download} to -retrieve the file. The meta data typically includes the mime-type, description, -a filename and other meta information, and possibly even the full original file +The URIs contain all the information required by +@command{gnunet-download} to retrieve the file. The meta data +typically includes the mime-type, description, a filename and +other meta information, and possibly even the full original file (if it was small). @node File-sharing Namespace Management @subsection File-sharing Namespace Management @c %**end of header -THIS TEXT IS OUTDATED AND NEEDS TO BE REWRITTEN FOR 0.10! +@b{Please note that the text in this subsection is outdated and needs} +@b{to be rewritten for version 0.10!} -The gnunet-pseudonym tool can be used to create pseudonyms and to advertise -namespaces. By default, gnunet-pseudonym simply lists all locally available -pseudonyms. +The gnunet-pseudonym tool can be used to create pseudonyms and +to advertise namespaces. By default, gnunet-pseudonym simply +lists all locally available pseudonyms. @menu @@ -1142,60 +1256,66 @@ pseudonyms. @subsubsection Creating Pseudonyms @c %**end of header -With the @command{-C NICK} option it can also be used to create a new pseudonym. -A pseudonym is the virtual identity of the entity in control of a namespace. -Anyone can create any number of pseudonyms. Note that creating a pseudonym can -take a few minutes depending on the performance of the machine used. +With the @command{-C NICK} option it can also be used to +create a new pseudonym. A pseudonym is the virtual identity +of the entity in control of a namespace. Anyone can create +any number of pseudonyms. Note that creating a pseudonym can +take a few minutes depending on the performance of the machine +used. @node Deleting Pseudonyms @subsubsection Deleting Pseudonyms @c %**end of header -With the @command{-D NICK} option pseudonyms can be deleted. Once the pseudonym has -been deleted it is impossible to add content to the corresponding namespace. -Deleting the pseudonym does not make the namespace or any content in it +With the @command{-D NICK} option pseudonyms can be deleted. +Once the pseudonym has been deleted it is impossible to add +content to the corresponding namespace. Deleting the +pseudonym does not make the namespace or any content in it unavailable. @node Advertising namespaces @subsubsection Advertising namespaces @c %**end of header -Each namespace is associated with meta-data that describes the namespace. -This meta data is provided by the user at the time that the namespace is -advertised. Advertisements are published under keywords so that they can be -found using normal keyword-searches. This way, users can learn about new +Each namespace is associated with meta-data that describes +the namespace. This meta data is provided by the user at +the time that the namespace is advertised. Advertisements +are published under keywords so that they can be found using +normal keyword-searches. This way, users can learn about new namespaces without relying on out-of-band communication or directories. A suggested keyword to use for all namespaces is simply "namespace". -When a keyword-search finds a namespace advertisement, it is automatically -stored in a local list of known namespaces. Users can then associate a rank with -the namespace to remember the quality of the content found in it. +When a keyword-search finds a namespace advertisement, +it is automatically stored in a local list of known namespaces. +Users can then associate a rank with the namespace to remember +the quality of the content found in it. @node Namespace names @subsubsection Namespace names @c %**end of header -While the namespace is uniquely identified by its ID, another way to refer to -the namespace is to use the NICKNAME. The NICKNAME can be freely chosen by the -creator of the namespace and hence conflicts are possible. If a GNUnet client -learns about more than one namespace using the same NICKNAME, the ID is appended +While the namespace is uniquely identified by its ID, another way +to refer to the namespace is to use the NICKNAME. +The NICKNAME can be freely chosen by the creator of the namespace and +hence conflicts are possible. If a GNUnet client learns about more +than one namespace using the same NICKNAME, the ID is appended to the NICKNAME to get a unique identifier. @node Namespace root @subsubsection Namespace root @c %**end of header -An item of particular interest in the namespace advertisement is the ROOT. -The ROOT is the identifier of a designated entry in the namespace. The idea is -that the ROOT can be used to advertise an entry point to the content of the -namespace. +An item of particular interest in the namespace advertisement is +the ROOT. The ROOT is the identifier of a designated entry in the +namespace. The idea is that the ROOT can be used to advertise an +entry point to the content of the namespace. @node File-Sharing URIs @subsection File-Sharing URIs @c %**end of header -GNUnet (currently) uses four different types of URIs for file-sharing. They all -begin with "gnunet://fs/". This section describes the four different URI types -in detail. +GNUnet (currently) uses four different types of URIs for +file-sharing. They all begin with "gnunet://fs/". +This section describes the four different URI types in detail. @menu @@ -1210,60 +1330,68 @@ in detail. @subsubsection Encoding of hash values in URIs @c %**end of header -Most URIs include some hash values. Hashes are encoded using base32hex -(RFC 2938). +Most URIs include some hash values. Hashes are encoded using +base32hex (RFC 2938). @node Content Hash Key (chk) @subsubsection Content Hash Key (chk) @c %**end of header -A chk-URI is used to (uniquely) identify a file or directory and to allow peers -to download the file. Files are stored in GNUnet as a tree of encrypted blocks. -The chk-URI thus contains the information to download and decrypt those blocks. -A chk-URI has the format "gnunet://fs/chk/KEYHASH.QUERYHASH.SIZE". Here, "SIZE" -is the size of the file (which allows a peer to determine the shape of the -tree), KEYHASH is the key used to decrypt the file (also the hash of the -plaintext of the top block) and QUERYHASH is the query used to request the -top-level block (also the hash of the encrypted block). +A chk-URI is used to (uniquely) identify a file or directory +and to allow peers to download the file. Files are stored in +GNUnet as a tree of encrypted blocks. +The chk-URI thus contains the information to download and decrypt +those blocks. A chk-URI has the format +"gnunet://fs/chk/KEYHASH.QUERYHASH.SIZE". Here, "SIZE" +is the size of the file (which allows a peer to determine the +shape of the tree), KEYHASH is the key used to decrypt the file +(also the hash of the plaintext of the top block) and QUERYHASH +is the query used to request the top-level block (also the hash +of the encrypted block). @node Location identifiers (loc) @subsubsection Location identifiers (loc) @c %**end of header -For non-anonymous file-sharing, loc-URIs are used to specify which peer is -offering the data (in addition to specifying all of the data from a chk-URI). -Location identifiers include a digital signature of the peer to affirm that the -peer is truly the origin of the data. The format is -"gnunet://fs/loc/KEYHASH.QUERYHASH.SIZE.PEER.SIG.EXPTIME". Here, "PEER" is the -public key of the peer (in GNUnet format in base32hex), SIG is the RSA signature -(in GNUnet format in base32hex) and EXPTIME specifies when the signature expires +For non-anonymous file-sharing, loc-URIs are used to specify which +peer is offering the data (in addition to specifying all of the +data from a chk-URI). Location identifiers include a digital +signature of the peer to affirm that the peer is truly the +origin of the data. The format is +"gnunet://fs/loc/KEYHASH.QUERYHASH.SIZE.PEER.SIG.EXPTIME". +Here, "PEER" is the public key of the peer (in GNUnet format in +base32hex), SIG is the RSA signature (in GNUnet format in +base32hex) and EXPTIME specifies when the signature expires (in milliseconds after 1970). @node Keyword queries (ksk) @subsubsection Keyword queries (ksk) @c %**end of header -A keyword-URI is used to specify that the desired operation is the search using -a particular keyword. The format is simply "gnunet://fs/ksk/KEYWORD". Non-ASCII -characters can be specified using the typical URI-encoding (using hex values) -from HTTP. "+" can be used to specify multiple keywords (which are then -logically "OR"-ed in the search, results matching both keywords are given a -higher rank): "gnunet://fs/ksk/KEYWORD1+KEYWORD2". +A keyword-URI is used to specify that the desired operation +is the search using a particular keyword. The format is simply +"gnunet://fs/ksk/KEYWORD". Non-ASCII characters can be specified +using the typical URI-encoding (using hex values) from HTTP. +"+" can be used to specify multiple keywords (which are then +logically "OR"-ed in the search, results matching both keywords +are given a higher rank): "gnunet://fs/ksk/KEYWORD1+KEYWORD2". @node Namespace content (sks) @subsubsection Namespace content (sks) @c %**end of header Namespaces are sets of files that have been approved by some (usually -pseudonymous) user --- typically by that user publishing all of the files -together. A file can be in many namespaces. A file is in a namespace if the -owner of the ego (aka the namespace's private key) signs the CHK of the file -cryptographically. An SKS-URI is used to search a namespace. The result is a -block containing meta data, the CHK and the namespace owner's signature. The -format of a sks-URI is "gnunet://fs/sks/NAMESPACE/IDENTIFIER". Here, "NAMESPACE" -is the public key for the namespace. "IDENTIFIER" is a freely chosen keyword -(or password!). A commonly used identifier is "root" which by convention refers -to some kind of index or other entry point into the namespace. +pseudonymous) user --- typically by that user publishing all of the +files together. A file can be in many namespaces. A file is in a +namespace if the owner of the ego (aka the namespace's private key) +signs the CHK of the file cryptographically. An SKS-URI is used to +search a namespace. The result is a block containing meta data, +the CHK and the namespace owner's signature. The format of a sks-URI +is "gnunet://fs/sks/NAMESPACE/IDENTIFIER". Here, "NAMESPACE" +is the public key for the namespace. "IDENTIFIER" is a freely +chosen keyword (or password!). A commonly used identifier is +"root" which by convention refers to some kind of index or other +entry point into the namespace. @node The GNU Name System @section The GNU Name System @@ -1282,17 +1410,19 @@ GNS is designed to provide: @item Compatibility with DNS @end itemize -For the initial configuration and population of your GNS installation, please -follow the GNS setup instructions. The remainder of this chapter will provide -some background on GNS and then describe how to use GNS in more detail. - -Unlike DNS, GNS does not rely on central root zones or authorities. Instead any -user administers his own root and can can create arbitrary name value mappings. -Furthermore users can delegate resolution to other users' zones just like DNS NS -records do. Zones are uniquely identified via public keys and resource records -are signed using the corresponding public key. Delegation to another user's zone -is done using special PKEY records and petnames. A petname is a name that can be -freely chosen by the user. This results in non-unique name-value mappings as +For the initial configuration and population of your +GNS installation, please follow the GNS setup instructions. +The remainder of this chapter will provide some background on GNS +and then describe how to use GNS in more detail. + +Unlike DNS, GNS does not rely on central root zones or authorities. +Instead any user administers their own root and can can create arbitrary +name value mappings. Furthermore users can delegate resolution to other +users' zones just like DNS NS records do. Zones are uniquely identified +via public keys and resource records are signed using the corresponding +public key. Delegation to another user's zone is done using special PKEY +records and petnames. A petname is a name that can be freely chosen by +the user. This results in non-unique name-value mappings as @code{@uref{http://www.bob.gnu/, www.bob.gnu}} to one user might be @code{@uref{http://www.friend.gnu/, www.friend.gnu}} for someone else. @@ -1319,103 +1449,121 @@ To setup your GNS system you must execute: $ gnunet-gns-import.sh @end example +@noindent This will boostrap your zones and create the necessary key material. -Your keys can be listed using the gnunet-identity command line tool: +Your keys can be listed using the @command{gnunet-identity} +command line tool: @example $ gnunet-identity -d @end example -You can arbitrarily create your own zones using the gnunet-identity tool using: +@noindent +You can arbitrarily create your own zones using the gnunet-identity +tool using: @example $ gnunet-identity -C "new_zone" @end example +@noindent Now you can add (or edit, or remove) records in your GNS zone using the -gnunet-setup GUI or using the gnunet-namestore command-line tool. In either -case, your records will be stored in an SQL database under control of the -gnunet-service-namestore. Note that if mutliple users use one peer, the -namestore database will include the combined records of all users. However, -users will not be able to see each other's records if they are marked as -private. - -To provide a simple example for editing your own zone, suppose you have your own -web server with IP 1.2.3.4. Then you can put an A record (A records in DNS are -for IPv4 IP addresses) into your local zone using the command:@ +gnunet-setup GUI or using the gnunet-namestore command-line tool. +In either case, your records will be stored in an SQL database under +control of the gnunet-service-namestore. Note that if multiple users +use one peer, the namestore database will include the combined records +of all users. However, users will not be able to see each other's records +if they are marked as private. + +To provide a simple example for editing your own zone, suppose you +have your own web server with IP 1.2.3.4. Then you can put an +A record (A records in DNS are for IPv4 IP addresses) into your +local zone using the command: @example $ gnunet-namestore -z master-zone -a -n www -t A -V 1.2.3.4 -e never @end example -Afterwards, you will be able to access your webpage under "www.gnu" (assuming -your webserver does not use virtual hosting, if it does, please read up on -setting up the GNS proxy). +@noindent +Afterwards, you will be able to access your webpage under "www.gnu" +(assuming your webserver does not use virtual hosting, if it does, +please read up on setting up the GNS proxy). -Similar commands will work for other types of DNS and GNS records, the syntax -largely depending on the type of the record. Naturally, most users may find -editing the zones using the gnunet-setup GUI to be easier. +Similar commands will work for other types of DNS and GNS records, +the syntax largely depending on the type of the record. +Naturally, most users may find editing the zones using the +@command{gnunet-setup} GUI to be easier. @node Obtaining your Zone Key @subsection Obtaining your Zone Key Each zone in GNS has a public-private key. Usually, gnunet-namestore and -gnunet-setup will access your private key as necessary, so you do not have to -worry about those. What is important is your public key (or rather, the hash of -your public key), as you will likely want to give it to others so that they can -securely link to you. +gnunet-setup will access your private key as necessary, so you do not +have to worry about those. What is important is your public key +(or rather, the hash of your public key), as you will likely want to +give it to others so that they can securely link to you. -You can usually get the hash of your public key using@ +You can usually get the hash of your public key using @example $ gnunet-identity -d $options | grep master-zone | awk '@{print $3@}' @end example +@noindent For example, the output might be something like: @example DC3SEECJORPHQNVRH965A6N74B1M37S721IG4RBQ15PJLLPJKUE0 @end example -Alternatively, you can obtain a QR code with your zone key AND your pseudonym -from gnunet-gtk. The QR code is displayed in the GNS tab and can be stored to -disk using the Save as button next to the image. +@noindent +Alternatively, you can obtain a QR code with your zone key AND +your pseudonym from gnunet-gtk. The QR code is displayed in the +GNS tab and can be stored to disk using the Save as button next +to the image. @node Adding Links to Other Zones @subsection Adding Links to Other Zones -A central operation in GNS is the ability to securely delegate to other zones. -Basically, by adding a delegation you make all of the names from the other zone -available to yourself. This section describes how to create delegations. +A central operation in GNS is the ability to securely delegate to +other zones. Basically, by adding a delegation you make all of the +names from the other zone available to yourself. This section +describes how to create delegations. -Suppose you have a friend who you call 'bob' who also uses GNS. You can then -delegate resolution of names to Bob's zone by adding a PKEY record to his local -zone: +Suppose you have a friend who you call 'bob' who also uses GNS. +You can then delegate resolution of names to Bob's zone by adding +a PKEY record to their local zone: @example $ gnunet-namestore -a -n bob --type PKEY -V XXXX -e never @end example -Note that XXXX in the command above must be replaced with the hash of Bob's -public key (the output your friend obtained using the gnunet-identity command -from the previous section and told you, for example by giving you a business -card containing this information as a QR code). - -Assuming Bob has an A record for his website under the name of www in his zone, -you can then access Bob's website under www.bob.gnu --- as well as any (public) -GNS record that Bob has in his zone by replacing www with the respective name of -the record in Bob's zone. - -Furthermore, if Bob has himself a (public) delegation to Carol's zone under -"carol", you can access Carol's records under NAME.carol.bob.gnu (where NAME is -the name of Carol's record you want to access). +@noindent +Note that XXXX in the command above must be replaced with the +hash of Bob's public key (the output your friend obtained using +the gnunet-identity command from the previous section and told you, +for example by giving you a business card containing this +information as a QR code). + +Assuming Bob has an A record for their website under the name of +www in his zone, you can then access Bob's website under +www.bob.gnu --- as well as any (public) GNS record that Bob has +in their zone by replacing www with the respective name of the +record in Bob's zone. + +@c themselves? themself? +Furthermore, if Bob has themselves a (public) delegation to Carol's +zone under "carol", you can access Carol's records under +NAME.carol.bob.gnu (where NAME is the name of Carol's record you +want to access). @node The Three Local Zones of GNS @subsection The Three Local Zones of GNS -Each user GNS has control over three zones. Each of the zones has a different -purpose. These zones are the +Each user GNS has control over three zones. Each of the zones +has a different purpose. These zones are the + @itemize @bullet @item master zone, @@ -1427,70 +1575,74 @@ purpose. These zones are the @subsection The Master Zone -The master zone is your personal TLD. Names within the @code{.gnu} namespace are -resolved relative to this zone. You can arbitrarily add records to this zone and -selectively publish those records. +The master zone is your personal TLD. Names within the @code{.gnu} +namespace are resolved relative to this zone. You can arbitrarily +add records to this zone and selectively publish those records. @node The Private Zone @subsection The Private Zone -The private zone is a subzone (or subdomain in DNS terms) of your master zone. -It should be used for records that you want to keep private. For example -@code{bank.private.gnu}. The key idea is that you want to keep your private -records separate, if just to know that those names are not available to other -users. +The private zone is a subzone (or subdomain in DNS terms) of your +master zone. It should be used for records that you want to keep +private. For example @code{bank.private.gnu}. The key idea is that +you want to keep your private records separate, if just to know +that those names are not available to other users. @node The Shorten Zone @subsection The Shorten Zone -The shorten zone can either be a subzone of the master zone or the private zone. -It is different from the other zones in that GNS will automatically populate -this zone with other users' zones based on their PSEU records whenever you -resolve a name. +The shorten zone can either be a subzone of the master zone or the +private zone. It is different from the other zones in that GNS +will automatically populate this zone with other users' zones based +on their PSEU records whenever you resolve a name. For example if you go to -@code{@uref{http://www.bob.alice.dave.gnu/, www.bob.alice.dave.gnu}}, GNS will -try to import @code{bob} into your shorten zone. Having obtained Bob's PKEY from -@code{alice.dave.gnu}, GNS will lookup the PSEU record for @code{+} in Bob's -zone. If it exists and the specified pseudonym is not taken, Bob's PKEY will be -automatically added under that pseudonym (i.e. "bob") into your shorten zone. -From then on, Bob's webpage will also be available for you as -@code{@uref{http://www.bob.short.gnu/, www.bob.short.gnu}}. This feature is -called automatic name shortening and is supposed to keep GNS names as short and -memorable as possible. +@code{@uref{http://www.bob.alice.dave.gnu/, www.bob.alice.dave.gnu}}, +GNS will try to import @code{bob} into your shorten zone. Having +obtained Bob's PKEY from @code{alice.dave.gnu}, GNS will lookup the +PSEU record for @code{+} in Bob's zone. If it exists and the specified +pseudonym is not taken, Bob's PKEY will be automatically added under +that pseudonym (i.e. "bob") into your shorten zone. From then on, +Bob's webpage will also be available for you as +@code{@uref{http://www.bob.short.gnu/, www.bob.short.gnu}}. +This feature is called @b{automatic name shortening} and is supposed to +keep GNS names as short and memorable as possible. @node The ZKEY Top Level Domain in GNS @subsection The ZKEY Top Level Domain in GNS GNS also provides a secure and globally unique namespace under the .zkey -top-level domain. A name in the .zkey TLD corresponds to the (printable) public -key of a zone. Names in the .zkey TLD are then resolved by querying the -respective zone. The .zkey TLD is expected to be used under rare circumstances -where globally unique names are required and for integration with legacy -systems. +top-level domain. A name in the .zkey TLD corresponds to the (printable) +public key of a zone. Names in the .zkey TLD are then resolved by querying +the respective zone. The .zkey TLD is expected to be used under rare +circumstances where globally unique names are required and for +integration with legacy systems. @node Resource Records in GNS @subsection Resource Records in GNS GNS supports the majority of the DNS records as defined in -@uref{http://www.ietf.org/rfc/rfc1035.txt, RFC 1035}. Additionally, GNS defines -some new record types the are unique to the GNS system. For example, -GNS-specific resource records are use to give petnames for zone delegation, -revoke zone keys and provide some compatibility features. - -For some DNS records, GNS does extended processing to increase their usefulness -in GNS. In particular, GNS introduces special names referred to as -"zone relative names". Zone relative names are allowed in some resource record -types (for example, in NS and CNAME records) and can also be used in links on -webpages. Zone relative names end in ".+" which indicates that the name needs to -be resolved relative to the current authoritative zone. The extended processing -of those names will expand the ".+" with the correct delegation chain to the -authoritative zone (replacing ".+" with the name of the location where the name -was encountered) and hence generate a valid @code{.gnu} name. +@uref{http://www.ietf.org/rfc/rfc1035.txt, RFC 1035}. Additionally, +GNS defines some new record types the are unique to the GNS system. +For example, GNS-specific resource records are used to give petnames +for zone delegation, revoke zone keys and provide some compatibility +features. + +For some DNS records, GNS does extended processing to increase their +usefulness in GNS. In particular, GNS introduces special names +referred to as "zone relative names". Zone relative names are allowed +in some resource record types (for example, in NS and CNAME records) +and can also be used in links on webpages. Zone relative names end +in ".+" which indicates that the name needs to be resolved relative +to the current authoritative zone. The extended processing of those +names will expand the ".+" with the correct delegation chain to the +authoritative zone (replacing ".+" with the name of the location +where the name was encountered) and hence generate a +valid @code{.gnu} name. GNS currently supports the following record types: @@ -1510,10 +1662,10 @@ GNS currently supports the following record types: @subsubsection NICK A NICK record is used to give a zone a name. With a NICK record, you can -essentially specify how you would like to be called. GNS expects this record -under the name "+" in the zone's database (NAMESTORE); however, it will then -automatically be copied into each record set, so that clients never need to do a -separate lookup to discover the NICK record. +essentially specify how you would like to be called. GNS expects this +record under the name "+" in the zone's database (NAMESTORE); however, +it will then automatically be copied into each record set, so that +clients never need to do a separate lookup to discover the NICK record. @b{Example}@ @@ -1521,57 +1673,65 @@ separate lookup to discover the NICK record. Name: +; RRType: NICK; Value: bob @end example -This record in Bob's zone will tell other users that this zone wants to be -referred to as 'bob'. Note that nobody is obliged to call Bob's zone 'bob' in -their own zones. It can be seen as a recommendation ("Please call me 'bob'"). +@noindent +This record in Bob's zone will tell other users that this zone wants +to be referred to as 'bob'. Note that nobody is obliged to call Bob's +zone 'bob' in their own zones. It can be seen as a +recommendation ("Please call me 'bob'"). @node PKEY @subsubsection PKEY -PKEY records are used to add delegation to other users' zones and give those -zones a petname. +PKEY records are used to add delegation to other users' zones and +give those zones a petname. @b{Example}@ -Let Bob's zone be identified by the hash "ABC012". Bob is your friend so you -want to give him the petname "friend". Then you add the following record to your -zone: +Let Bob's zone be identified by the hash "ABC012". Bob is your friend +so you want to give them the petname "friend". Then you add the +following record to your zone: @example Name: friend; RRType: PKEY; Value: ABC012; @end example -This will allow you to resolve records in bob's zone under "*.friend.gnu". +@noindent +This will allow you to resolve records in bob's zone +under "*.friend.gnu". @node BOX @subsubsection BOX -BOX records are there to integrate information from TLSA or SRV records under -the main label. In DNS, TLSA and SRV records use special names of the form -@code{_port._proto.(label.)*tld} to indicate the port number and protocol -(i.e. tcp or udp) for which the TLSA or SRV record is valid. This causes various -problems, and is elegantly solved in GNS by integrating the protocol and port -numbers together with the respective value into a "BOX" record. Note that in the -GUI, you do not get to edit BOX records directly right now --- the GUI will -provide the illusion of directly editing the TLSA and SRV records, even though -they internally are BOXed up. +BOX records are there to integrate information from TLSA or +SRV records under the main label. In DNS, TLSA and SRV records +use special names of the form @code{_port._proto.(label.)*tld} to +indicate the port number and protocol (i.e. tcp or udp) for which +the TLSA or SRV record is valid. This causes various problems, and +is elegantly solved in GNS by integrating the protocol and port +numbers together with the respective value into a "BOX" record. +Note that in the GUI, you do not get to edit BOX records directly +right now --- the GUI will provide the illusion of directly +editing the TLSA and SRV records, even though they internally +are BOXed up. @node LEHO @subsubsection LEHO -The LEgacy HOstname of a server. Some webservers expect a specific hostname to -provide a service (virtiual hosting). Also SSL certificates usually contain DNS -names. To provide the expected legacy DNS name for a server, the LEHO record can -be used. To mitigate the just mentioned issues the GNS proxy has to be used. The -GNS proxy will use the LEHO information to apply the necessary transformations. +The LEgacy HOstname of a server. Some webservers expect a specific +hostname to provide a service (virtiual hosting). Also SSL +certificates usually contain DNS names. To provide the expected +legacy DNS name for a server, the LEHO record can be used. +To mitigate the just mentioned issues the GNS proxy has to be used. +The GNS proxy will use the LEHO information to apply the necessary +transformations. @node VPN @subsubsection VPN GNS allows easy access to services provided by the GNUnet Virtual Public -Network. When the GNS resolver encounters a VPN record it will contact the VPN -service to try and allocate an IPv4/v6 address (if the queries record type is an -IP address) that can be used to contact the service. +Network. When the GNS resolver encounters a VPN record it will contact +the VPN service to try and allocate an IPv4/v6 address (if the queries +record type is an IP address) that can be used to contact the service. @b{Example}@ @@ -1580,8 +1740,9 @@ ABC012:@ Name: www; RRType: VPN; Value: 80 ABC012 web.gnu. The peer ABC012 is configured to provide an exit point for the service -"web.gnu." on port 80 to it's server running locally on port 8080 by having the -following lines in the @file{gnunet.conf} configuration file:@ +"web.gnu." on port 80 to it's server running locally on port 8080 by +having the following lines in the @file{gnunet.conf} configuration file: + @example [web.gnunet.] TCP_REDIRECTS = 80:localhost4:8080 @@ -1595,20 +1756,23 @@ Those records work in exactly the same fashion as in traditional DNS. @node CNAME @subsubsection CNAME -As specified in RFC 1035 whenever a CNAME is encountered the query needs to be -restarted with the specified name. In GNS a CNAME can either be: +As specified in RFC 1035 whenever a CNAME is encountered the query +needs to be restarted with the specified name. In GNS a CNAME +can either be: @itemize @bullet @item A zone relative name, @item A zkey name or -@item A DNS name (in which case resolution will continue outside of GNS with the systems DNS resolver) +@item A DNS name (in which case resolution will continue outside +of GNS with the systems DNS resolver) @end itemize @node GNS2DNS @subsubsection GNS2DNS -GNS can delegate authority to a legacy DNS zone. For this, the name of the DNS -nameserver and the name of the DNS zone are specified in a GNS2DNS record. +GNS can delegate authority to a legacy DNS zone. For this, the +name of the DNS nameserver and the name of the DNS zone are +specified in a GNS2DNS record. @b{Example} @@ -1616,44 +1780,49 @@ nameserver and the name of the DNS zone are specified in a GNS2DNS record. Name: pet; RRType: GNS2DNS; Value: gnunet.org@@a.ns.joker.com @end example +@noindent Any query to @code{pet.gnu} will then be delegated to the DNS server at -@code{a.ns.joker.com}.@ -For example, @code{@uref{http://www.pet.gnu/, www.pet.gnu}} will result in a -DNS query for @code{@uref{http://www.gnunet.org/, www.gnunet.org}} to the server -at @code{a.ns.joker.com}. Delegation to DNS via NS records in GNS can be useful -if you do not want to start resolution in the DNS root zone (due to issues such -as censorship or availability). - -Note that you would typically want to use a relative name for the nameserver, -i.e. +@code{a.ns.joker.com}. For example, +@code{@uref{http://www.pet.gnu/, www.pet.gnu}} will result in a DNS query +for @code{@uref{http://www.gnunet.org/, www.gnunet.org}} to the server +at @code{a.ns.joker.com}. Delegation to DNS via NS records in GNS can +be useful if you do not want to start resolution in the DNS root zone +(due to issues such as censorship or availability). + +Note that you would typically want to use a relative name for the +nameserver, i.e. + @example Name: pet; RRType: GNS2DNS; Value: gnunet.org@@ns-joker.+@ Name: ns-joker; RRType: A; Value: 184.172.157.218 @end example +@noindent This way, you can avoid involving the DNS hierarchy in the resolution of -@code{a.ns.joker.com}. In the example above, the problem may not be obvious as -the nameserver for "gnunet.org" is in the ".com" zone. However, imagine the -nameserver was "ns.gnunet.org". In this case, delegating to "ns.gnunet.org" -would mean that despite using GNS, censorship in the DNS ".org" zone would still -be effective. +@code{a.ns.joker.com}. In the example above, the problem may not be +obvious as the nameserver for "gnunet.org" is in the ".com" zone. +However, imagine the nameserver was "ns.gnunet.org". In this case, +delegating to "ns.gnunet.org" would mean that despite using GNS, +censorship in the DNS ".org" zone would still be effective. @node SOA SRV PTR and MX @subsubsection SOA SRV PTR and MX The domain names in those records can, again, be either + @itemize @bullet @item A zone relative name, @item A zkey name or @item A DNS name @end itemize -The resolver will expand the zone relative name if possible. Note that when -using MX records within GNS, the target mail server might still refuse to accept -e-mails to the resulting domain as the name might not match. GNS-enabled mail -clients should use the ZKEY zone as the destination hostname and GNS-enabled -mail servers should be configured to accept e-mails to the ZKEY-zones of all -local users. +The resolver will expand the zone relative name if possible. +Note that when using MX records within GNS, the target mail +server might still refuse to accept e-mails to the resulting +domain as the name might not match. GNS-enabled mail clients +should use the ZKEY zone as the destination hostname and +GNS-enabled mail servers should be configured to accept +e-mails to the ZKEY-zones of all local users. @node Using the Virtual Public Network @section Using the Virtual Public Network @@ -1664,156 +1833,177 @@ local users. * Setting up VPN node for protocol translation and tunneling:: @end menu -Using the GNUnet Virtual Public Network (VPN) application you can tunnel IP -traffic over GNUnet. Moreover, the VPN comes with built-in protocol translation -and DNS-ALG support, enabling IPv4-to-IPv6 protocol translation -(in both directions). This chapter documents how to use the GNUnet VPN. - -The first thing to note about the GNUnet VPN is that it is a public network. All -participating peers can participate and there is no secret key to control -access. So unlike common virtual private networks, the GNUnet VPN is not useful -as a means to provide a "private" network abstraction over the Internet. The -GNUnet VPN is a virtual network in the sense that it is an overlay over the -Internet, using its own routing mechanisms and can also use an internal -addressing scheme. The GNUnet VPN is an Internet underlay --- TCP/IP -applications run on top of it. - -The VPN is currently only supported on GNU/Linux systems. Support for operating -systems that support TUN (such as FreeBSD) should be easy to add (or might not -even require any coding at all --- we just did not test this so far). Support -for other operating systems would require re-writing the code to create virtual +Using the GNUnet Virtual Public Network (VPN) application you can +tunnel IP traffic over GNUnet. Moreover, the VPN comes +with built-in protocol translation and DNS-ALG support, enabling +IPv4-to-IPv6 protocol translation (in both directions). +This chapter documents how to use the GNUnet VPN. + +The first thing to note about the GNUnet VPN is that it is a public +network. All participating peers can participate and there is no +secret key to control access. So unlike common virtual private +networks, the GNUnet VPN is not useful as a means to provide a +"private" network abstraction over the Internet. The GNUnet VPN +is a virtual network in the sense that it is an overlay over the +Internet, using its own routing mechanisms and can also use an +internal addressing scheme. The GNUnet VPN is an Internet +underlay --- TCP/IP applications run on top of it. + +The VPN is currently only supported on GNU/Linux systems. +Support for operating systems that support TUN (such as FreeBSD) +should be easy to add (or might not even require any coding at +all --- we just did not test this so far). Support for other +operating systems would require re-writing the code to create virtual network interfaces and to intercept DNS requests. -The VPN does not provide good anonymity. While requests are routed over the -GNUnet network, other peers can directly see the source and destination of each -(encapsulated) IP packet. Finally, if you use the VPN to access Internet -services, the peer sending the request to the Internet will be able to observe -and even alter the IP traffic. We will discuss additional security implications +The VPN does not provide good anonymity. While requests are routed +over the GNUnet network, other peers can directly see the source +and destination of each (encapsulated) IP packet. Finally, if you +use the VPN to access Internet services, the peer sending the +request to the Internet will be able to observe and even alter +the IP traffic. We will discuss additional security implications of using the VPN later in this chapter. @node Setting up an Exit node @subsection Setting up an Exit node -Any useful operation with the VPN requires the existence of an exit node in the -GNUnet Peer-to-Peer network. Exit functionality can only be enabled on peers -that have regular Internet access. If you want to play around with the VPN or -support the network, we encourage you to setup exit nodes. This chapter -documents how to setup an exit node. +Any useful operation with the VPN requires the existence of an exit +node in the GNUnet Peer-to-Peer network. Exit functionality can only +be enabled on peers that have regular Internet access. If you want +to play around with the VPN or support the network, we encourage +you to setup exit nodes. This chapter documents how to setup an +exit node. + +There are four types of exit functions an exit node can provide, +and using the GNUnet VPN to access the Internet will only work +nicely if the first three types are provided somewhere in +the network. The four exit functions are: -There are four types of exit functions an exit node can provide, and using the -GNUnet VPN to access the Internet will only work nicely if the first three types -are provided somewhere in the network. The four exit functions are: @itemize @bullet @item DNS: allow other peers to use your DNS resolver @item IPv4: allow other peers to access your IPv4 Internet connection @item IPv6: allow other peers to access your IPv6 Internet connection -@item Local service: allow other peers to access a specific TCP or UDP service your peer is providing +@item Local service: allow other peers to access a specific TCP or +UDP service your peer is providing @end itemize -By enabling "exit" in gnunet-setup and checking the respective boxes in the -"exit" tab, you can easily choose which of the above exit functions you want to -support. +By enabling "exit" in gnunet-setup and checking the respective boxes +in the "exit" tab, you can easily choose which of the above exit +functions you want to support. -Note, however, that by supporting the first three functions you will allow -arbitrary other GNUnet users to access the Internet via your system. This is -somewhat similar to running a Tor exit node. The torproject has a nice article -about what to consider if you want to do this here. We believe that generally -running a DNS exit node is completely harmless. +Note, however, that by supporting the first three functions you will +allow arbitrary other GNUnet users to access the Internet via your +system. This is somewhat similar to running a Tor exit node. The +Torproject has a nice article about what to consider if you want +to do this here. We believe that generally running a DNS exit node +is completely harmless. The exit node configuration does currently not allow you to restrict the -Internet traffic that leaves your system. In particular, you cannot exclude SMTP -traffic (or block port 25) or limit to HTTP traffic using the GNUnet -configuration. However, you can use your host firewall to restrict outbound -connections from the virtual tunnel interface. This is highly recommended. In -the future, we plan to offer a wider range of configuration options for exit -nodes. - -Note that by running an exit node GNUnet will configure your kernel to perform -IP-forwarding (for IPv6) and NAT (for IPv4) so that the traffic from the virtual -interface can be routed to the Internet. In order to provide an IPv6-exit, you -need to have a subnet routed to your host's external network interface and -assign a subrange of that subnet to the GNUnet exit's TUN interface. - -When running a local service, you should make sure that the local service is -(also) bound to the IP address of your EXIT interface (i.e. 169.254.86.1). It -will NOT work if your local service is just bound to loopback. You may also want -to create a "VPN" record in your zone of the GNU Name System to make it easy for -others to access your service via a name instead of just the full service -descriptor. Note that the identifier you assign the service can serve as a -passphrase or shared secret, clients connecting to the service must somehow -learn the service's name. VPN records in the GNU Name System can make this -easier. +Internet traffic that leaves your system. In particular, you cannot +exclude SMTP traffic (or block port 25) or limit to HTTP traffic using +the GNUnet configuration. However, you can use your host firewall to +restrict outbound connections from the virtual tunnel interface. This +is highly recommended. In the future, we plan to offer a wider range +of configuration options for exit nodes. + +Note that by running an exit node GNUnet will configure your kernel +to perform IP-forwarding (for IPv6) and NAT (for IPv4) so that the +traffic from the virtual interface can be routed to the Internet. +In order to provide an IPv6-exit, you need to have a subnet routed +to your host's external network interface and assign a subrange of +that subnet to the GNUnet exit's TUN interface. + +When running a local service, you should make sure that the local +service is (also) bound to the IP address of your EXIT interface +(i.e. 169.254.86.1). It will NOT work if your local service is +just bound to loopback. You may also want to create a "VPN" record +in your zone of the GNU Name System to make it easy for others to +access your service via a name instead of just the full service +descriptor. Note that the identifier you assign the service can +serve as a passphrase or shared secret, clients connecting to the +service must somehow learn the service's name. VPN records in the +GNU Name System can make this easier. @node Fedora and the Firewall @subsection Fedora and the Firewall -When using an exit node on Fedora 15, the standard firewall can create trouble -even when not really exiting the local system! For IPv4, the standard rules seem -fine. However, for IPv6 the standard rules prohibit traffic from the network -range of the virtual interface created by the exit daemon to the local IPv6 -address of the same interface (which is essentially loopback traffic, so you -might suspect that a standard firewall would leave this traffic alone). However, -as somehow for IPv6 the traffic is not recognized as originating from the local -system (and as the connection is not already "established"), the firewall drops -the traffic. You should still get ICMPv6 packets back, but that's obviously not -very useful. - -Possible ways to fix this include disabling the firewall (do you have a good -reason for having it on?) or disabling the firewall at least for the GNUnet exit -interface (or the respective IPv4/IPv6 address range). The best way to diagnose -these kinds of problems in general involves setting the firewall to REJECT -instead of DROP and to watch the traffic using wireshark (or tcpdump) to see if -ICMP messages are generated when running some tests that should work. +When using an exit node on Fedora 15, the standard firewall can +create trouble even when not really exiting the local system! +For IPv4, the standard rules seem fine. However, for IPv6 the +standard rules prohibit traffic from the network range of the +virtual interface created by the exit daemon to the local IPv6 +address of the same interface (which is essentially loopback +traffic, so you might suspect that a standard firewall would +leave this traffic alone). However, as somehow for IPv6 the +traffic is not recognized as originating from the local +system (and as the connection is not already "established"), +the firewall drops the traffic. You should still get ICMPv6 +packets back, but that's obviously not very useful. + +Possible ways to fix this include disabling the firewall (do you +have a good reason for having it on?) or disabling the firewall +at least for the GNUnet exit interface (or the respective +IPv4/IPv6 address range). The best way to diagnose these kinds +of problems in general involves setting the firewall to REJECT +instead of DROP and to watch the traffic using wireshark +(or tcpdump) to see if ICMP messages are generated when running +some tests that should work. @node Setting up VPN node for protocol translation and tunneling @subsection Setting up VPN node for protocol translation and tunneling -The GNUnet VPN/PT subsystem enables you to tunnel IP traffic over the VPN to an -exit node, from where it can then be forwarded to the Internet. This section -documents how to setup VPN/PT on a node. Note that you can enable both the VPN -and an exit on the same peer. In this case, IP traffic from your system may -enter your peer's VPN and leave your peer's exit. This can be useful as a means -to do protocol translation. For example, you might have an application that -supports only IPv4 but needs to access an IPv6-only site. In this case, GNUnet -would perform 4to6 protocol translation between the VPN (IPv4) and the -Exit (IPv6). Similarly, 6to4 protocol translation is also possible. However, the -primary use for GNUnet would be to access an Internet service running with an -IP version that is not supported by your ISP. In this case, your IP traffic -would be routed via GNUnet to a peer that has access to the Internet with the -desired IP version. - -Setting up an entry node into the GNUnet VPN primarily requires you to enable -the "VPN/PT" option in "gnunet-setup". This will launch the -"gnunet-service-vpn", "gnunet-service-dns" and "gnunet-daemon-pt" processes. -The "gnunet-service-vpn" will create a virtual interface which will be used as -the target for your IP traffic that enters the VPN. Additionally, a second -virtual interface will be created by the "gnunet-service-dns" for your DNS -traffic. You will then need to specify which traffic you want to tunnel over -GNUnet. If your ISP only provides you with IPv4 or IPv6-access, you may choose -to tunnel the other IP protocol over the GNUnet VPN. If you do not have an ISP -(and are connected to other GNUnet peers via WLAN), you can also choose to -tunnel all IP traffic over GNUnet. This might also provide you with some -anonymity. After you enable the respective options and restart your peer, your -Internet traffic should be tunneled over the GNUnet VPN. - -The GNUnet VPN uses DNS-ALG to hijack your IP traffic. Whenever an application -resolves a hostname (i.e. 'gnunet.org'), the "gnunet-daemon-pt" will instruct -the "gnunet-service-dns" to intercept the request (possibly route it over GNUnet -as well) and replace the normal answer with an IP in the range of the VPN's -interface. "gnunet-daemon-pt" will then tell "gnunet-service-vpn" to forward all +The GNUnet VPN/PT subsystem enables you to tunnel IP traffic over the +VPN to an exit node, from where it can then be forwarded to the +Internet. This section documents how to setup VPN/PT on a node. +Note that you can enable both the VPN and an exit on the same peer. +In this case, IP traffic from your system may enter your peer's VPN +and leave your peer's exit. This can be useful as a means to do +protocol translation. For example, you might have an application that +supports only IPv4 but needs to access an IPv6-only site. In this case, +GNUnet would perform 4to6 protocol translation between the VPN (IPv4) +and the Exit (IPv6). Similarly, 6to4 protocol translation is also +possible. However, the primary use for GNUnet would be to access +an Internet service running with an IP version that is not supported +by your ISP. In this case, your IP traffic would be routed via GNUnet +to a peer that has access to the Internet with the desired IP version. + +Setting up an entry node into the GNUnet VPN primarily requires you +to enable the "VPN/PT" option in "gnunet-setup". This will launch the +"gnunet-service-vpn", "gnunet-service-dns" and "gnunet-daemon-pt" +processes. The "gnunet-service-vpn" will create a virtual interface +which will be used as the target for your IP traffic that enters the +VPN. Additionally, a second virtual interface will be created by +the "gnunet-service-dns" for your DNS traffic. You will then need to +specify which traffic you want to tunnel over GNUnet. If your ISP only +provides you with IPv4 or IPv6-access, you may choose to tunnel the +other IP protocol over the GNUnet VPN. If you do not have an ISP +(and are connected to other GNUnet peers via WLAN), you can also +choose to tunnel all IP traffic over GNUnet. This might also provide +you with some anonymity. After you enable the respective options +and restart your peer, your Internet traffic should be tunneled +over the GNUnet VPN. + +The GNUnet VPN uses DNS-ALG to hijack your IP traffic. Whenever an +application resolves a hostname (i.e. 'gnunet.org'), the +"gnunet-daemon-pt" will instruct the "gnunet-service-dns" to intercept +the request (possibly route it over GNUnet as well) and replace the +normal answer with an IP in the range of the VPN's interface. +"gnunet-daemon-pt" will then tell "gnunet-service-vpn" to forward all traffic it receives on the TUN interface via the VPN to the original destination. -For applications that do not use DNS, you can also manually create such a -mapping using the gnunet-vpn command-line tool. Here, you specfiy the desired -address family of the result (i.e. "-4"), and the intended target IP on the -Internet ("-i 131.159.74.67") and "gnunet-vpn" will tell you which IP address in -the range of your VPN tunnel was mapped. - -gnunet-vpn can also be used to access "internal" services offered by GNUnet -nodes. So if you happen to know a peer and a service offered by that peer, you -can create an IP tunnel to that peer by specifying the peer's identity, service -name and protocol (--tcp or --udp) and you will again receive an IP address that -will terminate at the respective peer's service. +For applications that do not use DNS, you can also manually create +such a mapping using the gnunet-vpn command-line tool. Here, you +specfiy the desired address family of the result (i.e. "-4"), and the +intended target IP on the Internet ("-i 131.159.74.67") and +"gnunet-vpn" will tell you which IP address in the range of your +VPN tunnel was mapped. + +@command{gnunet-vpn} can also be used to access "internal" services +offered by GNUnet nodes. So if you happen to know a peer and a +service offered by that peer, you can create an IP tunnel to +that peer by specifying the peer's identity, service name and +protocol (--tcp or --udp) and you will again receive an IP address +that will terminate at the respective peer's service. -- 2.25.1