X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fhello%2Fhello.c;h=690a0961a34ffaa344277748415c8fe9a2c3db80;hb=7c1f035ed971e12882cd7a65c7d36883842945b1;hp=4ddeebd037f3c7f78444391b5bf1c5f8ab1cc2ba;hpb=d9dda7eda6b55b311982d99885aafd82448a057e;p=oweals%2Fgnunet.git diff --git a/src/hello/hello.c b/src/hello/hello.c index 4ddeebd03..690a0961a 100644 --- a/src/hello/hello.c +++ b/src/hello/hello.c @@ -1,10 +1,10 @@ /* This file is part of GNUnet. - (C) 2009 Christian Grothoff (and other contributing authors) + Copyright (C) 2009, 2015 GNUnet e.V. GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published - by the Free Software Foundation; either version 2, or (at your + by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but @@ -14,89 +14,120 @@ You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the - Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. + Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. */ /** * @file hello/hello.c * @brief helper library for handling HELLOs * @author Christian Grothoff + * @author Matthias Wachs */ #include "platform.h" #include "gnunet_hello_lib.h" #include "gnunet_protocols.h" -#include "gnunet_server_lib.h" +#include "gnunet_util_lib.h" +#include "gnunet_transport_plugin.h" /** - * A HELLO message is used to exchange information about - * transports with other peers. This struct is always - * followed by the actual network addresses which have - * the format: - * - * 1) transport-name (0-terminated) - * 2) address-length (uint32_t, network byte order; possibly - * unaligned!) - * 3) address expiration (GNUNET_TIME_AbsoluteNBO); possibly - * unaligned!) - * 4) address (address-length bytes; possibly unaligned!) + * Context used for building our own URI. */ -struct GNUNET_HELLO_Message +struct GNUNET_HELLO_ComposeUriContext { /** - * Type will be GNUNET_MESSAGE_TYPE_HELLO. + * Final URI. */ - struct GNUNET_MessageHeader header; + char *uri; /** - * Always zero (for alignment). + * Function for finding transport plugins by name. */ - uint32_t reserved GNUNET_PACKED; + GNUNET_HELLO_TransportPluginsFind plugins_find; +}; + + +/** + * Context for #add_address_to_hello(). + */ +struct GNUNET_HELLO_ParseUriContext +{ + /** + * Position in the URI with the next address to parse. + */ + const char *pos; /** - * The public key of the peer. + * Set to #GNUNET_SYSERR to indicate parse errors. */ - struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded publicKey; + int ret; + /** + * Counter + */ + unsigned int counter_total; + + /** + * Counter skipped addresses + */ + unsigned int counter_added; + + /** + * Function for finding transport plugins by name. + */ + GNUNET_HELLO_TransportPluginsFind plugins_find; }; +/** + * Return HELLO type + * + * @param h HELLO Message to test + * @return #GNUNET_YES for friend-only or #GNUNET_NO otherwise + */ +int +GNUNET_HELLO_is_friend_only (const struct GNUNET_HELLO_Message *h) +{ + if (GNUNET_YES == ntohl(h->friend_only)) + return GNUNET_YES; + return GNUNET_NO; +} + + /** * Copy the given address information into * the given buffer using the format of HELLOs. * - * @param tname name of the transport plugin - * @param expiration expiration for the address - * @param addr the address - * @param addr_len length of the address in bytes - * @param target where to copy the address + * @param address the address + * @param expiration expiration for the @a address + * @param target where to copy the @a address * @param max maximum number of bytes to copy to target * @return number of bytes copied, 0 if * the target buffer was not big enough. */ size_t -GNUNET_HELLO_add_address (const char *tname, +GNUNET_HELLO_add_address (const struct GNUNET_HELLO_Address *address, struct GNUNET_TIME_Absolute expiration, - const void *addr, - size_t addr_len, char *target, size_t max) + char *target, + size_t max) { - uint32_t alen; + uint16_t alen; size_t slen; struct GNUNET_TIME_AbsoluteNBO exp; - slen = strlen (tname) + 1; - if (slen + sizeof (uint32_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO) + - addr_len > max) + slen = strlen (address->transport_name) + 1; + if (slen + sizeof (uint16_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO) + + address->address_length > max) return 0; exp = GNUNET_TIME_absolute_hton (expiration); - alen = htonl ((uint32_t) addr_len); - memcpy (target, tname, slen); - memcpy (&target[slen], &alen, sizeof (uint32_t)); - slen += sizeof (uint32_t); - memcpy (&target[slen], &exp, sizeof (struct GNUNET_TIME_AbsoluteNBO)); + alen = htons ((uint16_t) address->address_length); + GNUNET_memcpy (target, address->transport_name, slen); + GNUNET_memcpy (&target[slen], &alen, sizeof (uint16_t)); + slen += sizeof (uint16_t); + GNUNET_memcpy (&target[slen], &exp, sizeof (struct GNUNET_TIME_AbsoluteNBO)); slen += sizeof (struct GNUNET_TIME_AbsoluteNBO); - memcpy (&target[slen], addr, addr_len); - slen += addr_len; + GNUNET_memcpy (&target[slen], address->address, address->address_length); + slen += address->address_length; return slen; } @@ -105,15 +136,17 @@ GNUNET_HELLO_add_address (const char *tname, * Get the size of an address entry in a HELLO message. * * @param buf pointer to the start of the address entry - * @param max maximum size of the entry (end of buf) + * @param max maximum size of the entry (end of @a buf) * @param ralen set to the address length - * @return size of the entry, or 0 if max is not large enough + * @return size of the entry, or 0 if @a max is not large enough */ static size_t -get_hello_address_size (const char *buf, size_t max, uint32_t * ralen) +get_hello_address_size (const char *buf, + size_t max, + uint16_t *ralen) { const char *pos; - uint32_t alen; + uint16_t alen; size_t left; size_t slen; @@ -121,35 +154,34 @@ get_hello_address_size (const char *buf, size_t max, uint32_t * ralen) pos = buf; slen = 1; while ((left > 0) && ('\0' != *pos)) - { - left--; - pos++; - slen++; - } - if ('\0' != *pos) - { - /* 0-termination not found */ - GNUNET_break_op (0); - abort (); - return 0; - } + { + left--; + pos++; + slen++; + } + if (0 == left) + { + /* 0-termination not found */ + GNUNET_break_op (0); + return 0; + } pos++; - if (left < sizeof (uint32_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO)) - { - /* not enough space for addrlen */ - GNUNET_break_op (0); - return 0; - } - memcpy (&alen, pos, sizeof (uint32_t)); - alen = ntohl (alen); + if (left < sizeof (uint16_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO)) + { + /* not enough space for addrlen */ + GNUNET_break_op (0); + return 0; + } + GNUNET_memcpy (&alen, pos, sizeof (uint16_t)); + alen = ntohs (alen); *ralen = alen; - slen += alen + sizeof (uint32_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO); + slen += alen + sizeof (uint16_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO); if (max < slen) - { - /* not enough space for addr */ - GNUNET_break_op (0); - return 0; - } + { + /* not enough space for addr */ + GNUNET_break_op (0); + return 0; + } return slen; } @@ -159,37 +191,51 @@ get_hello_address_size (const char *buf, size_t max, uint32_t * ralen) * expiration time and an iterator that spews the * transport addresses. * + * If friend only is set to #GNUNET_YES we create a FRIEND_HELLO which + * will not be gossiped to other peers. + * + * @param public_key public key to include in the HELLO + * @param addrgen callback to invoke to get addresses + * @param addrgen_cls closure for @a addrgen + * @param friend_only should the returned HELLO be only visible to friends? * @return the hello message */ struct GNUNET_HELLO_Message * -GNUNET_HELLO_create (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded - *publicKey, +GNUNET_HELLO_create (const struct GNUNET_CRYPTO_EddsaPublicKey *public_key, GNUNET_HELLO_GenerateAddressListCallback addrgen, - void *addrgen_cls) + void *addrgen_cls, + int friend_only) { - char buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE - 256 - + char buffer[GNUNET_MAX_MESSAGE_SIZE - 1 - 256 - sizeof (struct GNUNET_HELLO_Message)]; size_t max; size_t used; size_t ret; struct GNUNET_HELLO_Message *hello; + GNUNET_assert (NULL != public_key); + GNUNET_assert ( (GNUNET_YES == friend_only) || + (GNUNET_NO == friend_only) ); max = sizeof (buffer); used = 0; - if (addrgen != NULL) + if (NULL != addrgen) + { + while (GNUNET_SYSERR != (ret = addrgen (addrgen_cls, + max, + &buffer[used]))) { - while (0 != (ret = addrgen (addrgen_cls, max, &buffer[used]))) - { - max -= ret; - used += ret; - } + max -= ret; + used += ret; } + } hello = GNUNET_malloc (sizeof (struct GNUNET_HELLO_Message) + used); hello->header.type = htons (GNUNET_MESSAGE_TYPE_HELLO); hello->header.size = htons (sizeof (struct GNUNET_HELLO_Message) + used); - memcpy (&hello->publicKey, publicKey, - sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded)); - memcpy (&hello[1], buffer, used); + hello->friend_only = htonl (friend_only); + hello->publicKey = *public_key; + GNUNET_memcpy (&hello[1], + buffer, + used); return hello; } @@ -201,13 +247,16 @@ GNUNET_HELLO_create (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded * @param return_modified if a modified copy should be returned, * otherwise NULL will be returned * @param it iterator to call on each address - * @param it_cls closure for it + * @param it_cls closure for @a it + * @return modified HELLO message */ struct GNUNET_HELLO_Message * GNUNET_HELLO_iterate_addresses (const struct GNUNET_HELLO_Message *msg, int return_modified, - GNUNET_HELLO_AddressIterator it, void *it_cls) + GNUNET_HELLO_AddressIterator it, + void *it_cls) { + struct GNUNET_HELLO_Address address; uint16_t msize; struct GNUNET_HELLO_Message *ret; const char *inptr; @@ -215,151 +264,248 @@ GNUNET_HELLO_iterate_addresses (const struct GNUNET_HELLO_Message *msg, size_t esize; size_t wpos; char *woff; - uint32_t alen; + uint16_t alen; struct GNUNET_TIME_AbsoluteNBO expire; int iret; msize = GNUNET_HELLO_size (msg); if ((msize < sizeof (struct GNUNET_HELLO_Message)) || (ntohs (msg->header.type) != GNUNET_MESSAGE_TYPE_HELLO)) + { + GNUNET_break_op (0); return NULL; + } ret = NULL; if (return_modified) - { - ret = GNUNET_malloc (msize); - memcpy (ret, msg, msize); - } + { + ret = GNUNET_malloc (msize); + GNUNET_memcpy (ret, + msg, + msize); + } inptr = (const char *) &msg[1]; insize = msize - sizeof (struct GNUNET_HELLO_Message); wpos = 0; - woff = (ret != NULL) ? (char *) &ret[1] : NULL; + woff = (NULL != ret) ? (char *) &ret[1] : NULL; + address.peer.public_key = msg->publicKey; + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "HELLO has %u bytes of address data\n", + (unsigned int) insize); + while (insize > 0) + { + esize = get_hello_address_size (inptr, + insize, + &alen); + if (0 == esize) { - esize = get_hello_address_size (inptr, insize, &alen); - if (esize == 0) - { - GNUNET_break (0); - GNUNET_free_non_null (ret); - return NULL; - } - memcpy (&expire, - &inptr[esize - alen - sizeof (struct GNUNET_TIME_AbsoluteNBO)], - sizeof (struct GNUNET_TIME_AbsoluteNBO)); - iret = it (it_cls, - inptr, - GNUNET_TIME_absolute_ntoh (expire), - &inptr[esize - alen], alen); - if (iret == GNUNET_SYSERR) - { - if (ret != NULL) - ret->header.size = - ntohs (sizeof (struct GNUNET_HELLO_Message) + wpos); - return ret; - } - if ((iret == GNUNET_OK) && (ret != NULL)) - { - memcpy (woff, inptr, esize); - woff += esize; - wpos += esize; - } - insize -= esize; - inptr += esize; + GNUNET_break (0); + GNUNET_free_non_null (ret); + return NULL; } - if (ret != NULL) + /* need GNUNET_memcpy() due to possibility of misalignment */ + GNUNET_memcpy (&expire, + &inptr[esize - alen - sizeof (struct GNUNET_TIME_AbsoluteNBO)], + sizeof (struct GNUNET_TIME_AbsoluteNBO)); + address.address = &inptr[esize - alen]; + address.address_length = alen; + address.transport_name = inptr; + address.local_info = GNUNET_HELLO_ADDRESS_INFO_NONE; + iret = it (it_cls, + &address, + GNUNET_TIME_absolute_ntoh (expire)); + if (GNUNET_SYSERR == iret) + break; + if ( (GNUNET_OK == iret) && + (NULL != ret) ) + { + /* copy address over */ + GNUNET_memcpy (woff, + inptr, + esize); + woff += esize; + wpos += esize; + } + insize -= esize; + inptr += esize; + } + if (NULL != ret) ret->header.size = ntohs (sizeof (struct GNUNET_HELLO_Message) + wpos); return ret; } +/** + * Closure for #get_match_exp(). + */ struct ExpireContext { - const void *addr; - const char *tname; - size_t addrlen; + /** + * Address we are looking for. + */ + const struct GNUNET_HELLO_Address *address; + + /** + * Set to #GNUNET_YES if we found the @e address. + */ int found; + + /** + * Set to the expiration of the match if @e found is #GNUNET_YES. + */ struct GNUNET_TIME_Absolute expiration; }; +/** + * Store the expiration time of an address that matches the template. + * + * @param cls the `struct ExpireContext` + * @param address address to match against the template + * @param expiration expiration time of @a address, to store in @a cls + * @return #GNUNET_SYSERR if we found a matching address, #GNUNET_OK otherwise + */ static int get_match_exp (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, size_t addrlen) + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) { struct ExpireContext *ec = cls; - if ( (addrlen == ec->addrlen) && - (0 == memcmp (addr, ec->addr, addrlen)) && - (0 == strcmp (tname, ec->tname)) ) - { - ec->found = GNUNET_YES; - ec->expiration = expiration; - return GNUNET_SYSERR; /* done here */ - } - return GNUNET_OK; + if (0 != GNUNET_HELLO_address_cmp (address, + ec->address)) + return GNUNET_OK; + ec->found = GNUNET_YES; + ec->expiration = expiration; + return GNUNET_SYSERR; /* done here */ } +/** + * Context for a #GNUNET_HELLO_Merge operation. + */ struct MergeContext { + /** + * First HELLO we are merging. + */ const struct GNUNET_HELLO_Message *h1; + + /** + * Second HELLO we are merging. + */ const struct GNUNET_HELLO_Message *h2; + + /** + * Either @e h1 or @e h2, used when copying + * to compare against (so we only copy the + * most recent entry). + */ const struct GNUNET_HELLO_Message *other; + + /** + * Buffer where we copy to. + */ char *buf; + + /** + * Number of bytes allocated in @e buf + */ size_t max; + + /** + * Current (write) offset in @e buf. + */ size_t ret; + + /** + * Should we copy addresses with an identical value + * and expiration time in @e other, or do we only + * copy addresses with strictly later expiration times? + */ int take_equal; }; +/** + * Append the address @a address to the buffer from + * the merge context IF it is more recent than equivalent + * addresses in `other`. + * + * @param cls the `struct MergeContext` + * @param address the HELLO address we might copy + * @param expiration expiration time for @a address + * @return always #GNUNET_OK + */ static int copy_latest (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, size_t addrlen) + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) { struct MergeContext *mc = cls; struct ExpireContext ec; - ec.addr = addr; - ec.addrlen = addrlen; + ec.address = address; ec.found = GNUNET_NO; - ec.tname = tname; - GNUNET_HELLO_iterate_addresses (mc->other, GNUNET_NO, &get_match_exp, &ec); - if ( (ec.found == GNUNET_NO) || - (ec.expiration.value < expiration.value) || - ( (ec.expiration.value == expiration.value) && - (mc->take_equal == GNUNET_YES) ) ) - { - mc->ret += GNUNET_HELLO_add_address (tname, - expiration, - addr, - addrlen, - &mc->buf[mc->ret], - mc->max - mc->ret); - } + /* check if address exists in other */ + GNUNET_HELLO_iterate_addresses (mc->other, + GNUNET_NO, + &get_match_exp, + &ec); + if ( (GNUNET_NO == ec.found) || + (ec.expiration.abs_value_us < expiration.abs_value_us) || + ( (ec.expiration.abs_value_us == expiration.abs_value_us) && + (GNUNET_YES == mc->take_equal) ) ) + { + /* copy address to buffer */ + mc->ret += + GNUNET_HELLO_add_address (address, + expiration, + &mc->buf[mc->ret], + mc->max - mc->ret); + } return GNUNET_OK; } -static size_t -merge_addr (void *cls, size_t max, void *buf) +/** + * Function called to build the HELLO during + * #GNUNET_HELLO_merge() by merging addresses from + * two original HELLOs. + * + * @param cls the `struct MergeContext` + * @param max number of bytes we can write at most in @a buf + * @param buf where to copy the addresses + * @return #GNUNET_SYSERR to end iteration, otherwise number of bytes written to @a buf + */ +static ssize_t +merge_addr (void *cls, + size_t max, + void *buf) { struct MergeContext *mc = cls; - if (mc->h1 == NULL) - return 0; + if (NULL == mc->h1) + return GNUNET_SYSERR; /* Stop iteration */ mc->ret = 0; mc->max = max; mc->buf = buf; mc->take_equal = GNUNET_NO; mc->other = mc->h2; - GNUNET_HELLO_iterate_addresses (mc->h1, GNUNET_NO, ©_latest, mc); + /* copy addresses from h1, if strictly larger expiration than h2 */ + GNUNET_HELLO_iterate_addresses (mc->h1, + GNUNET_NO, + ©_latest, + mc); mc->take_equal = GNUNET_YES; mc->other = mc->h1; - GNUNET_HELLO_iterate_addresses (mc->h2, GNUNET_NO, ©_latest, mc); + /* copy addresses from h2, if larger or equal expiration than h1 */ + GNUNET_HELLO_iterate_addresses (mc->h2, + GNUNET_NO, + ©_latest, + mc); + /* set marker to stop iteration */ mc->h1 = NULL; return mc->ret; } @@ -372,73 +518,111 @@ merge_addr (void *cls, size_t max, void *buf) * * @param h1 first HELLO message * @param h2 the second HELLO message - * @return the combined hello message + * @return the combined HELLO message */ struct GNUNET_HELLO_Message * GNUNET_HELLO_merge (const struct GNUNET_HELLO_Message *h1, const struct GNUNET_HELLO_Message *h2) { struct MergeContext mc = { h1, h2, NULL, NULL, 0, 0, 0 }; + int friend_only; - return GNUNET_HELLO_create (&h1->publicKey, &merge_addr, &mc); + if (h1->friend_only != h2->friend_only) + friend_only = GNUNET_YES; /* One of the HELLOs is friend only */ + else + friend_only = ntohl (h1->friend_only); /* Both HELLO's have the same type */ + + return GNUNET_HELLO_create (&h1->publicKey, + &merge_addr, + &mc, + friend_only); } +/** + * Context used in #GNUNET_HELLO_iterate_new_addresses() to + * figure out which addresses are in fact 'new'. + */ struct DeltaContext { + /** + * We should ignore addresses that expire before this time. + */ struct GNUNET_TIME_Absolute expiration_limit; + /** + * Function to call on addresses that are indeed new. + */ GNUNET_HELLO_AddressIterator it; + /** + * Closure for @e it. + */ void *it_cls; + /** + * HELLO with known addresses, addresses in this HELLO + * we must always ignore. + */ const struct GNUNET_HELLO_Message *old_hello; }; +/** + * Check if the given address is 'new', and if so, call + * the iterator. Compares the existing address against + * addresses in the context's `old_hello` and calls the + * iterator on those that are new (and not expired). + * + * @param cls the `struct DeltaContext` + * @param address an address to check whether it is new + * @param expiration expiration time for @a address + * @return #GNUNET_YES if the address is ignored, otherwise + * whatever the iterator returned. + */ static int delta_match (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, size_t addrlen) + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) { struct DeltaContext *dc = cls; int ret; struct ExpireContext ec; - ec.addr = addr; - ec.addrlen = addrlen; + ec.address = address; ec.found = GNUNET_NO; - ec.tname = tname; GNUNET_HELLO_iterate_addresses (dc->old_hello, - GNUNET_NO, &get_match_exp, &ec); - if ((ec.found == GNUNET_YES) && - ((ec.expiration.value > expiration.value) || - (ec.expiration.value >= dc->expiration_limit.value))) - return GNUNET_YES; /* skip */ - ret = dc->it (dc->it_cls, tname, expiration, addr, addrlen); + GNUNET_NO, + &get_match_exp, + &ec); + if ( (GNUNET_YES == ec.found) && + ( (ec.expiration.abs_value_us > expiration.abs_value_us) || + (ec.expiration.abs_value_us >= dc->expiration_limit.abs_value_us))) + return GNUNET_YES; /* skip: found and boring */ + ret = dc->it (dc->it_cls, + address, + expiration); return ret; } /** - * Iterate over addresses in "new_hello" that - * are NOT already present in "old_hello". + * Iterate over addresses in @a new_hello that are NOT already present + * in @a old_hello. Note that if the address is present in @a old_hello + * but the expiration time in @a new_hello is more recent, the iterator + * is also called. * * @param new_hello a HELLO message * @param old_hello a HELLO message - * @param expiration_limit ignore addresses in old_hello + * @param expiration_limit ignore addresses in @a old_hello * that expired before the given time stamp * @param it iterator to call on each address - * @param it_cls closure for it + * @param it_cls closure for @a it */ void -GNUNET_HELLO_iterate_new_addresses (const struct GNUNET_HELLO_Message - *new_hello, - const struct GNUNET_HELLO_Message - *old_hello, - struct GNUNET_TIME_Absolute - expiration_limit, +GNUNET_HELLO_iterate_new_addresses (const struct GNUNET_HELLO_Message *new_hello, + const struct GNUNET_HELLO_Message *old_hello, + struct GNUNET_TIME_Absolute expiration_limit, GNUNET_HELLO_AddressIterator it, void *it_cls) { @@ -448,7 +632,11 @@ GNUNET_HELLO_iterate_new_addresses (const struct GNUNET_HELLO_Message dc.it = it; dc.it_cls = it_cls; dc.old_hello = old_hello; - GNUNET_HELLO_iterate_addresses (new_hello, GNUNET_NO, &delta_match, &dc); + GNUNET_assert (NULL == + GNUNET_HELLO_iterate_addresses (new_hello, + GNUNET_NO, + &delta_match, + &dc)); } @@ -461,6 +649,7 @@ uint16_t GNUNET_HELLO_size (const struct GNUNET_HELLO_Message *hello) { uint16_t ret = ntohs (hello->header.size); + if ((ret < sizeof (struct GNUNET_HELLO_Message)) || (ntohs (hello->header.type) != GNUNET_MESSAGE_TYPE_HELLO)) return 0; @@ -468,48 +657,27 @@ GNUNET_HELLO_size (const struct GNUNET_HELLO_Message *hello) } -/** - * Get the public key from a HELLO message. - * - * @param hello the hello message - * @param publicKey where to copy the public key information, can be NULL - * @return GNUNET_SYSERR if the HELLO was malformed - */ -int -GNUNET_HELLO_get_key (const struct GNUNET_HELLO_Message *hello, - struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded - *publicKey) -{ - uint16_t ret = ntohs (hello->header.size); - if ((ret < sizeof (struct GNUNET_HELLO_Message)) || - (ntohs (hello->header.type) != GNUNET_MESSAGE_TYPE_HELLO)) - return GNUNET_SYSERR; - *publicKey = hello->publicKey; - return GNUNET_OK; -} - - /** * Get the peer identity from a HELLO message. * * @param hello the hello message * @param peer where to store the peer's identity - * @return GNUNET_SYSERR if the HELLO was malformed + * @return #GNUNET_SYSERR if the HELLO was malformed */ int GNUNET_HELLO_get_id (const struct GNUNET_HELLO_Message *hello, - struct GNUNET_PeerIdentity *peer) + struct GNUNET_PeerIdentity *peer) { uint16_t ret = ntohs (hello->header.size); + if ((ret < sizeof (struct GNUNET_HELLO_Message)) || (ntohs (hello->header.type) != GNUNET_MESSAGE_TYPE_HELLO)) return GNUNET_SYSERR; - GNUNET_CRYPTO_hash (&hello->publicKey, - sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded), - &peer->hashPubKey); + peer->public_key = hello->publicKey; return GNUNET_OK; } + /** * Get the header from a HELLO message, used so other code * can correctly send HELLO messages. @@ -522,6 +690,7 @@ struct GNUNET_MessageHeader * GNUNET_HELLO_get_header (struct GNUNET_HELLO_Message *hello) { uint16_t ret = ntohs (hello->header.size); + if ((ret < sizeof (struct GNUNET_HELLO_Message)) || (ntohs (hello->header.type) != GNUNET_MESSAGE_TYPE_HELLO)) return NULL; @@ -529,4 +698,571 @@ GNUNET_HELLO_get_header (struct GNUNET_HELLO_Message *hello) return &hello->header; } + +/** + * Context used for comparing HELLOs in #GNUNET_HELLO_equals(). + */ +struct EqualsContext +{ + /** + * Addresses that expired before this date are ignored for + * the comparisson. + */ + struct GNUNET_TIME_Absolute expiration_limit; + + /** + * Earliest expiration time for which we found a match + * with a difference in expiration times. + * At this time, the two HELLOs may start to diverge. + */ + struct GNUNET_TIME_Absolute result; + + /** + * HELLO message to compare against. (First set to the second + * HELLO, then set to the first HELLO.) + */ + const struct GNUNET_HELLO_Message *ref; + + /** + * Address we are currently looking for. + */ + const struct GNUNET_HELLO_Address *address; + + /** + * Expiration time of @e address. + */ + struct GNUNET_TIME_Absolute expiration; + + /** + * Did we find the address we were looking for? + */ + int found; + +}; + + +/** + * Check if the given address matches the address we are currently + * looking for. If so, sets `found` to #GNUNET_YES and, if the + * expiration times for the two addresses differ, updates `result` to + * the minimum of our @a expiration and the existing value + * + * @param cls the `struct EqualsContext` + * @param address address from the reference HELLO + * @param expiration expiration time for @a address + * @return #GNUNET_YES if the address is expired or does not match + * #GNUNET_SYSERR if the address does match. + */ +static int +find_other_matching (void *cls, + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) +{ + struct EqualsContext *ec = cls; + + if (expiration.abs_value_us < ec->expiration_limit.abs_value_us) + return GNUNET_YES; + if (0 == GNUNET_HELLO_address_cmp (address, ec->address)) + { + ec->found = GNUNET_YES; + if (expiration.abs_value_us < ec->expiration.abs_value_us) + ec->result = GNUNET_TIME_absolute_min (expiration, + ec->result); + return GNUNET_SYSERR; + } + return GNUNET_YES; +} + + +/** + * Helper function for #GNUNET_HELLO_equals(). Checks + * if the given @a address exists also in the other HELLO; + * if not, the result time is set to zero and the iteration + * is aborted. + * + * @param cls the `struct EqualsContext` + * @param address address to locate + * @param expiration expiration time of the current address + * @return #GNUNET_OK if the address exists or is expired, + * #GNUNET_SYSERR if it was not found + */ +static int +find_matching (void *cls, + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) +{ + struct EqualsContext *ec = cls; + + if (expiration.abs_value_us < ec->expiration_limit.abs_value_us) + return GNUNET_OK; /* expired, we don't care */ + ec->address = address; + ec->expiration = expiration; + ec->found = GNUNET_NO; + GNUNET_HELLO_iterate_addresses (ec->ref, + GNUNET_NO, + &find_other_matching, + ec); + if (GNUNET_NO == ec->found) + { + /* not found, we differ *now* */ + ec->result = GNUNET_TIME_UNIT_ZERO_ABS; + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * Test if two HELLO messages contain the same addresses. + * If they only differ in expiration time, the lowest + * expiration time larger than @a now where they differ + * is returned. + * + * @param h1 first HELLO message + * @param h2 the second HELLO message + * @param now time to use for deciding which addresses have + * expired and should not be considered at all + * @return absolute time forever if the two HELLOs are + * totally identical; smallest timestamp >= @a now if + * they only differ in timestamps; + * zero if the some addresses with expirations >= @a now + * do not match at all + */ +struct GNUNET_TIME_Absolute +GNUNET_HELLO_equals (const struct GNUNET_HELLO_Message *h1, + const struct GNUNET_HELLO_Message *h2, + struct GNUNET_TIME_Absolute now) +{ + struct EqualsContext ec; + + if (h1->header.type != h2->header.type) + return GNUNET_TIME_UNIT_ZERO_ABS; + if (0 != + memcmp (&h1->publicKey, + &h2->publicKey, + sizeof (struct GNUNET_CRYPTO_EddsaPublicKey))) + return GNUNET_TIME_UNIT_ZERO_ABS; + ec.expiration_limit = now; + ec.result = GNUNET_TIME_UNIT_FOREVER_ABS; + ec.ref = h2; + GNUNET_HELLO_iterate_addresses (h1, + GNUNET_NO, + &find_matching, + &ec); + if (ec.result.abs_value_us == GNUNET_TIME_UNIT_ZERO.rel_value_us) + return ec.result; + ec.ref = h1; + GNUNET_HELLO_iterate_addresses (h2, + GNUNET_NO, + &find_matching, + &ec); + return ec.result; +} + + +/** + * Iterator to find the time when the last address will expire. + * Updates the maximum value stored in @a cls. + * + * @param cls where to store the max, a `struct GNUNET_TIME_Absolute` + * @param address an address (ignored) + * @param expiration expiration time for @a address + * @return #GNUNET_OK (always) + */ +static int +find_max_expire (void *cls, + const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) +{ + struct GNUNET_TIME_Absolute *max = cls; + + *max = GNUNET_TIME_absolute_max (*max, expiration); + return GNUNET_OK; +} + + +/** + * When does the last address in the given HELLO expire? + * + * @param msg HELLO to inspect + * @return time the last address expires, 0 if there are no addresses in the HELLO + */ +struct GNUNET_TIME_Absolute +GNUNET_HELLO_get_last_expiration (const struct GNUNET_HELLO_Message *msg) +{ + struct GNUNET_TIME_Absolute ret; + + ret = GNUNET_TIME_UNIT_ZERO_ABS; + GNUNET_HELLO_iterate_addresses (msg, + GNUNET_NO, + &find_max_expire, + &ret); + return ret; +} + + +/** + * GNUnet URIs are of the general form "gnunet://MODULE/IDENTIFIER". + * The specific structure of "IDENTIFIER" depends on the module and + * maybe differenciated into additional subcategories if applicable. + * This module only deals with hello identifiers (MODULE = "hello"). + *
+ *
+ * The concrete URI format is:
+ *
+ * "gnunet://hello/PEER[+YYYYMMDDHHMMSS+
+ */
+
+
+
+/**
+ * Function that is called on each address of this peer.
+ * Expands the corresponding URI string.
+ *
+ * @param cls the `struct GNUNET_HELLO_ComposeUriContext`
+ * @param address address to add
+ * @param expiration expiration time for the address
+ * @return #GNUNET_OK (continue iteration).
+ */
+static int
+add_address_to_uri (void *cls,
+ const struct GNUNET_HELLO_Address *address,
+ struct GNUNET_TIME_Absolute expiration)
+{
+ struct GNUNET_HELLO_ComposeUriContext *ctx = cls;
+ struct GNUNET_TRANSPORT_PluginFunctions *papi;
+ const char *addr;
+ char *ret;
+ char *addr_dup;
+ char *pos;
+ char tbuf[16] = "";
+ char *client_str = "_client";
+ struct tm *t;
+ time_t seconds;
+
+ papi = ctx->plugins_find (address->transport_name);
+ if (NULL == papi)
+ {
+ /* Not an error - we might just not have the right plugin. */
+ return GNUNET_OK;
+ }
+ if (NULL == papi->address_to_string)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "URI conversion not implemented for plugin `%s'\n",
+ address->transport_name);
+ return GNUNET_OK;
+ }
+ addr = papi->address_to_string (papi->cls,
+ address->address,
+ address->address_length);
+ if ( (NULL == addr) ||
+ (0 == strlen(addr)) )
+ return GNUNET_OK;
+
+ addr_dup = GNUNET_strdup (addr);
+ if (NULL != (pos = strstr (addr_dup, "_server")))
+ GNUNET_memcpy (pos,
+ client_str,
+ strlen (client_str)); /* Replace all server addresses with client addresses */
+
+ seconds = expiration.abs_value_us / 1000LL / 1000LL;
+ t = gmtime (&seconds);
+
+ GNUNET_asprintf (&ret,
+ "%s%c%s%c%s%c%s",
+ ctx->uri,
+ GNUNET_HELLO_URI_SEP,
+ strftime (tbuf,
+ sizeof (tbuf),
+ "%Y%m%d%H%M%S",
+ t) ? tbuf : "0",
+ GNUNET_HELLO_URI_SEP,
+ address->transport_name,
+ GNUNET_HELLO_URI_SEP,
+ addr_dup);
+ GNUNET_free (addr_dup);
+ GNUNET_free (ctx->uri);
+ ctx->uri = ret;
+ return GNUNET_OK;
+}
+
+
+/**
+ * Compose a hello URI string from a hello message.
+ *
+ * @param hello Hello message
+ * @param plugins_find Function to find transport plugins by name
+ * @return Hello URI string
+ */
+char *
+GNUNET_HELLO_compose_uri (const struct GNUNET_HELLO_Message *hello,
+ GNUNET_HELLO_TransportPluginsFind plugins_find)
+{
+ struct GNUNET_HELLO_ComposeUriContext ctx;
+ char *pkey;
+
+ ctx.plugins_find = plugins_find;
+ pkey = GNUNET_CRYPTO_eddsa_public_key_to_string (&hello->publicKey);
+ GNUNET_asprintf (&ctx.uri,
+ "%s%s",
+ (GNUNET_YES == GNUNET_HELLO_is_friend_only (hello))
+ ? GNUNET_FRIEND_HELLO_URI_PREFIX
+ : GNUNET_HELLO_URI_PREFIX,
+ pkey);
+ GNUNET_free (pkey);
+ GNUNET_HELLO_iterate_addresses (hello,
+ GNUNET_NO,
+ &add_address_to_uri,
+ &ctx);
+ return ctx.uri;
+}
+
+
+/* ************************* Parse HELLO URI ********************* */
+
+
+/**
+ * We're building a HELLO. Parse the next address from the
+ * parsing context and append it.
+ *
+ * @param cls the `struct GNUNET_HELLO_ParseUriContext`
+ * @param max number of bytes available for HELLO construction
+ * @param buffer where to copy the next address (in binary format)
+ * @return number of bytes added to buffer, #GNUNET_SYSERR on error
+ */
+static ssize_t
+add_address_to_hello (void *cls,
+ size_t max,
+ void *buffer)
+{
+ struct GNUNET_HELLO_ParseUriContext *ctx = cls;
+ const char *tname;
+ const char *address;
+ char *uri_address;
+ const char *end;
+ char *plugin_name;
+ struct tm expiration_time;
+ time_t expiration_seconds;
+ struct GNUNET_TIME_Absolute expire;
+ struct GNUNET_TRANSPORT_PluginFunctions *papi;
+ void *addr;
+ size_t addr_len;
+ struct GNUNET_HELLO_Address haddr;
+ ssize_t ret;
+
+ if (NULL == ctx->pos)
+ return GNUNET_SYSERR;
+ if (GNUNET_HELLO_URI_SEP != ctx->pos[0])
+ {
+ ctx->ret = GNUNET_SYSERR;
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ ctx->pos++;
+
+ if ( ('0' == ctx->pos[0]) &&
+ (GNUNET_HELLO_URI_SEP == ctx->pos[1]) )
+ {
+ expire = GNUNET_TIME_UNIT_FOREVER_ABS;
+ tname = ctx->pos + 1;
+ }
+ else
+ {
+ memset (&expiration_time, 0, sizeof (expiration_time));
+ tname = strptime (ctx->pos,
+ "%Y%m%d%H%M%S",
+ &expiration_time);
+ if (NULL == tname)
+ {
+ ctx->ret = GNUNET_SYSERR;
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ _("Failed to parse HELLO message: missing expiration time\n"));
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+
+ expiration_seconds = mktime (&expiration_time);
+ if (expiration_seconds == (time_t) -1)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ _("Failed to parse HELLO message: invalid expiration time\n"));
+ ctx->ret = GNUNET_SYSERR;
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ expire.abs_value_us = expiration_seconds * 1000LL * 1000LL;
+ }
+ if (GNUNET_HELLO_URI_SEP != tname[0])
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ _("Failed to parse HELLO message: malformed\n"));
+ ctx->ret = GNUNET_SYSERR;
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ tname++;
+ address = strchr (tname,
+ (int) GNUNET_HELLO_URI_SEP);
+ if (NULL == address)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ _("Failed to parse HELLO message: missing transport plugin\n"));
+ ctx->ret = GNUNET_SYSERR;
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ address++;
+ end = strchr (address, (int) GNUNET_HELLO_URI_SEP);
+ ctx->pos = end;
+ ctx->counter_total ++;
+ plugin_name = GNUNET_strndup (tname, address - (tname+1));
+ papi = ctx->plugins_find (plugin_name);
+ if (NULL == papi)
+ {
+ /* Not an error - we might just not have the right plugin.
+ * Skip this part, advance to the next one and recurse.
+ * But only if this is not the end of string.
+ */
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ _("Plugin `%s' not found, skipping address\n"),
+ plugin_name);
+ GNUNET_free (plugin_name);
+ return 0;
+ }
+ if (NULL == papi->string_to_address)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ _("Plugin `%s' does not support URIs yet\n"),
+ plugin_name);
+ GNUNET_free (plugin_name);
+ GNUNET_break (0);
+ return 0;
+ }
+ uri_address = GNUNET_strndup (address, end - address);
+ if (GNUNET_OK !=
+ papi->string_to_address (papi->cls,
+ uri_address,
+ strlen (uri_address) + 1,
+ &addr,
+ &addr_len))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ _("Failed to parse `%s' as an address for plugin `%s'\n"),
+ uri_address,
+ plugin_name);
+ GNUNET_free (plugin_name);
+ GNUNET_free (uri_address);
+ return 0;
+ }
+ GNUNET_free (uri_address);
+ /* address.peer is unset - not used by add_address() */
+ haddr.address_length = addr_len;
+ haddr.address = addr;
+ haddr.transport_name = plugin_name;
+ ret = GNUNET_HELLO_add_address (&haddr,
+ expire,
+ buffer,
+ max);
+ ctx->counter_added ++;
+ GNUNET_free (addr);
+ GNUNET_free (plugin_name);
+ return ret;
+}
+
+
+/**
+ * Parse a hello URI string to a hello message.
+ *
+ * @param uri URI string to parse
+ * @param pubkey Pointer to struct where public key is parsed
+ * @param hello Pointer to struct where hello message is parsed
+ * @param plugins_find Function to find transport plugins by name
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR if the URI was invalid, #GNUNET_NO on other errors
+ */
+int
+GNUNET_HELLO_parse_uri (const char *uri,
+ struct GNUNET_CRYPTO_EddsaPublicKey *pubkey,
+ struct GNUNET_HELLO_Message **hello,
+ GNUNET_HELLO_TransportPluginsFind plugins_find)
+{
+ const char *pks;
+ const char *exc;
+ int friend_only;
+ struct GNUNET_HELLO_ParseUriContext ctx;
+
+ if (0 == strncmp (uri,
+ GNUNET_HELLO_URI_PREFIX,
+ strlen (GNUNET_HELLO_URI_PREFIX)))
+ {
+ pks = &uri[strlen (GNUNET_HELLO_URI_PREFIX)];
+ friend_only = GNUNET_NO;
+ }
+ else if (0 == strncmp (uri,
+ GNUNET_FRIEND_HELLO_URI_PREFIX,
+ strlen (GNUNET_FRIEND_HELLO_URI_PREFIX)))
+ {
+ pks = &uri[strlen (GNUNET_FRIEND_HELLO_URI_PREFIX)];
+ friend_only = GNUNET_YES;
+ }
+ else
+ return GNUNET_SYSERR;
+ exc = strchr (pks, GNUNET_HELLO_URI_SEP);
+
+ if (GNUNET_OK !=
+ GNUNET_STRINGS_string_to_data (pks,
+ (NULL == exc) ? strlen (pks) : (exc - pks),
+ (unsigned char *) pubkey,
+ sizeof (*pubkey)))
+ return GNUNET_SYSERR;
+
+ ctx.pos = exc;
+ ctx.ret = GNUNET_OK;
+ ctx.counter_total = 0;
+ ctx.counter_added = 0;
+ ctx.plugins_find = plugins_find;
+ *hello = GNUNET_HELLO_create (pubkey,
+ &add_address_to_hello,
+ &ctx,
+ friend_only);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "HELLO URI contained %u addresses, added %u addresses\n",
+ ctx.counter_total,
+ ctx.counter_added);
+
+ return ctx.ret;
+}
+
+
/* end of hello.c */
+ *
+ * The encoding for hexadecimal values is defined in the crypto_hash.c
+ * module in the gnunetutil library and discussed there.
+ *
+ * Examples:
+ *
+ * gnunet://hello/V8XXK9GAN5ZJFRFQP8MQX3D83BZTSBQVHKWWD0JPE63Z821906EG+20120302010059+TCP+192.168.0.1:2086+TCP+64.23.8.174:0
+ * gnunet://hello/V8XXK9GAN5ZJFRFQP8MQX3D83BZTSBQVHKWWD0JPE63Z821906EG+20120302010059+TCP+[2001:db8:85a3:8d3:1319:8a2e:370:7348]:2086
+ *
+ *