/*
This file is part of GNUnet.
- (C) 2001, 2002, 2003, 2004, 2005, 2006, 2010 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2010, 2011 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
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 include/gnunet_hello_lib.h
- * @brief helper library for handling HELLOs
* @author Christian Grothoff
+ * @file
+ * Helper library for handling HELLOs
+ *
+ * @defgroup hello Hello library
+ * Helper library for handling HELLOs
+ *
+ * @see [Documentation](https://gnunet.org/gnunets-hostlist-subsystem)
+ *
+ * @{
*/
#ifndef GNUNET_HELLO_LIB_H
#endif
#endif
-#include "gnunet_common.h"
-#include "gnunet_crypto_lib.h"
+#include "gnunet_util_lib.h"
+
+
+/**
+ * Prefix that every HELLO URI must start with.
+ */
+#define GNUNET_HELLO_URI_PREFIX "gnunet://hello/"
+
+/**
+ * Prefix that every FRIEND HELLO URI must start with.
+ */
+#define GNUNET_FRIEND_HELLO_URI_PREFIX "gnunet://friend-hello/"
+
+/**
+ * Separator used in HELLO URI
+ */
+#define GNUNET_HELLO_URI_SEP '+'
+
+
+/**
+ * Additional local information about an address
+ *
+ * These information are only valid for the local peer and are not serialized
+ * when a #GNUNET_HELLO_Message is created
+ */
+enum GNUNET_HELLO_AddressInfo
+{
+ /**
+ * No additional information
+ */
+ GNUNET_HELLO_ADDRESS_INFO_NONE = 0,
+
+ /**
+ * This is an inbound address and cannot be used to initiate an outbound
+ * connection to another peer
+ */
+ GNUNET_HELLO_ADDRESS_INFO_INBOUND = 1
+};
+
+
+/**
+ * An address for communicating with a peer. We frequently
+ * need this tuple and the components cannot really be
+ * separated. This is NOT the format that would be used
+ * on the wire.
+ */
+struct GNUNET_HELLO_Address
+{
+
+ /**
+ * For which peer is this an address?
+ */
+ struct GNUNET_PeerIdentity peer;
+
+ /**
+ * Name of the transport plugin enabling the communication using
+ * this address.
+ */
+ const char *transport_name;
+
+ /**
+ * Binary representation of the address (plugin-specific).
+ */
+ const void *address;
+
+ /**
+ * Number of bytes in @e address.
+ */
+ size_t address_length;
+
+ /**
+ * Extended information about address
+ *
+ * This field contains additional #GNUNET_HELLO_AddressInfo flags e.g.
+ * to indicate an address is inbound and cannot be used to initiate an
+ * outbound connection.
+ *
+ * These information are only valid for the local peer and are not serialized
+ * when a #GNUNET_HELLO_Message is created
+ */
+ enum GNUNET_HELLO_AddressInfo local_info;
+
+};
+
+
+/**
+ * Allocate an address struct.
+ *
+ * @param peer the peer
+ * @param transport_name plugin name
+ * @param address binary address
+ * @param address_length number of bytes in @a address
+ * @param local_info additional local information for the address
+ * @return the address struct
+ */
+struct GNUNET_HELLO_Address *
+GNUNET_HELLO_address_allocate (const struct GNUNET_PeerIdentity *peer,
+ const char *transport_name,
+ const void *address,
+ size_t address_length,
+ enum GNUNET_HELLO_AddressInfo local_info);
+
+
+/**
+ * Copy an address struct.
+ *
+ * @param address address to copy
+ * @return a copy of the address struct
+ */
+struct GNUNET_HELLO_Address *
+GNUNET_HELLO_address_copy (const struct GNUNET_HELLO_Address *address);
+
+
+/**
+ * Compare two addresses. Does NOT compare the peer identity,
+ * that is assumed already to match!
+ *
+ * @param a1 first address
+ * @param a2 second address
+ * @return 0 if the addresses are equal, -1 if @a a1< @a a2, 1 if @a a1> @a a2.
+ */
+int
+GNUNET_HELLO_address_cmp (const struct GNUNET_HELLO_Address *a1,
+ const struct GNUNET_HELLO_Address *a2);
+
+
+/**
+ * Get the size of an address struct.
+ *
+ * @param address address
+ * @return the size
+ */
+size_t
+GNUNET_HELLO_address_get_size (const struct GNUNET_HELLO_Address *address);
+
+
+/**
+ * Check if an address has a local option set
+ *
+ * @param address the address to check
+ * @param option the respective option to check for
+ * @return #GNUNET_YES or #GNUNET_NO
+ */
+int
+GNUNET_HELLO_address_check_option (const struct GNUNET_HELLO_Address *address,
+ enum GNUNET_HELLO_AddressInfo option);
+
+
+/**
+ * Free an address.
+ *
+ * @param addr address to free
+ */
+#define GNUNET_HELLO_address_free(addr) GNUNET_free(addr)
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
/**
* A HELLO message is used to exchange information about
- * transports with other peers. This struct is guaranteed
- * to start with a "GNUNET_MessageHeader", everything else
- * should be internal to the HELLO library.
+ * 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 (uint16_t, network byte order; possibly
+ * unaligned!)
+ * 3) address expiration (`struct GNUNET_TIME_AbsoluteNBO`); possibly
+ * unaligned!)
+ * 4) address (address-length bytes; possibly unaligned!)
+ */
+struct GNUNET_HELLO_Message
+{
+ /**
+ * Type will be #GNUNET_MESSAGE_TYPE_HELLO.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Use in F2F mode: Do not gossip this HELLO message
+ */
+ uint32_t friend_only GNUNET_PACKED;
+
+ /**
+ * The public key of the peer.
+ */
+ struct GNUNET_CRYPTO_EddsaPublicKey publicKey;
+
+};
+GNUNET_NETWORK_STRUCT_END
+
+
+
+/**
+ * Return HELLO type
+ *
+ * @param h HELLO Message to test
+ * @return #GNUNET_YES for friend-only or #GNUNET_NO otherwise
*/
-struct GNUNET_HELLO_Message;
+int
+GNUNET_HELLO_is_friend_only (const struct GNUNET_HELLO_Message *h);
/**
* Copy the given address information into
* the given buffer using the format of HELLOs.
*
- * @param tname name of the transport plugin
+ * @param address address to add
* @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 max maximum number of bytes to copy to target
+ * @param max maximum number of bytes to copy to @a 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);
/**
* Callback function used to fill a buffer of max bytes with a list of
* addresses in the format used by HELLOs. Should use
- * "GNUNET_HELLO_add_address" as a helper function.
+ * #GNUNET_HELLO_add_address() as a helper function.
*
* @param cls closure
- * @param max maximum number of bytes that can be written to buf
+ * @param max maximum number of bytes that can be written to @a buf
* @param buf where to write the address information
- * @return number of bytes written, 0 to signal the
+ * @return number of bytes written or 0, #GNUNET_SYSERR to signal the
* end of the iteration.
*/
-typedef size_t
- (*GNUNET_HELLO_GenerateAddressListCallback) (void *cls,
- size_t max, void *buf);
+typedef ssize_t
+(*GNUNET_HELLO_GenerateAddressListCallback) (void *cls,
+ size_t max,
+ void *buf);
/**
* 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_GenerateAddressListCallback
- addrgen, void *addrgen_cls);
+struct GNUNET_HELLO_Message *
+GNUNET_HELLO_create (const struct GNUNET_CRYPTO_EddsaPublicKey *public_key,
+ GNUNET_HELLO_GenerateAddressListCallback addrgen,
+ void *addrgen_cls,
+ int friend_only);
/**
* Return the size of the given HELLO message.
+ *
* @param hello to inspect
* @return the size, 0 if HELLO is invalid
*/
-uint16_t GNUNET_HELLO_size (const struct GNUNET_HELLO_Message *hello);
+uint16_t
+GNUNET_HELLO_size (const struct GNUNET_HELLO_Message *hello);
/**
* @param h2 the second 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 GNUNET_HELLO_Message *
+GNUNET_HELLO_merge (const struct GNUNET_HELLO_Message *h1,
+ const struct GNUNET_HELLO_Message *h2);
+/**
+ * Test if two HELLO messages contain the same addresses.
+ * If they only differ in expiration time, the lowest
+ * expiration time larger than '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 >= now if
+ * they only differ in timestamps;
+ * zero if the some addresses with expirations >= 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);
+
/**
* Iterator callback to go over all addresses.
*
* @param cls closure
- * @param tname name of the transport
+ * @param address the address
* @param expiration expiration time
- * @param addr the address
- * @param addrlen length of the address
- * @return GNUNET_OK to keep the address,
- * GNUNET_NO to delete it from the HELLO
- * GNUNET_SYSERR to stop iterating (but keep current address)
+ * @return #GNUNET_OK to keep the address,
+ * #GNUNET_NO to delete it from the HELLO
+ * #GNUNET_SYSERR to stop iterating (but keep current address)
*/
typedef int
- (*GNUNET_HELLO_AddressIterator) (void *cls,
- const char *tname,
- struct GNUNET_TIME_Absolute expiration,
- const void *addr, size_t addrlen);
+(*GNUNET_HELLO_AddressIterator) (void *cls,
+ const struct GNUNET_HELLO_Address *address,
+ struct GNUNET_TIME_Absolute expiration);
+
+
+/**
+ * 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);
/**
* @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 the modified HELLO or NULL
*/
-struct GNUNET_HELLO_Message *GNUNET_HELLO_iterate_addresses (const struct
- GNUNET_HELLO_Message
- *msg,
- int
- return_modified,
- GNUNET_HELLO_AddressIterator
- it,
- void *it_cls);
+struct GNUNET_HELLO_Message *
+GNUNET_HELLO_iterate_addresses (const struct GNUNET_HELLO_Message *msg,
+ int return_modified,
+ GNUNET_HELLO_AddressIterator it, void *it_cls);
/**
- * 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
* 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);
/**
- * Get the public key from a HELLO message.
+ * Get the peer identity 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
+ * @param peer where to store the peer's identity
+ * @return #GNUNET_SYSERR if the HELLO was malformed
*/
int
-GNUNET_HELLO_get_key (const struct GNUNET_HELLO_Message *hello,
- struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded
- *publicKey);
+GNUNET_HELLO_get_id (const struct GNUNET_HELLO_Message *hello,
+ struct GNUNET_PeerIdentity *peer);
/**
- * Get the peer identity from a HELLO message.
+ * Get the header from a HELLO message, used so other code
+ * can correctly send HELLO messages.
*
* @param hello the hello message
- * @param peer where to store the peer's identity
- * @return GNUNET_SYSERR if the HELLO was malformed
+ *
+ * @return header or NULL if the HELLO was malformed
+ */
+struct GNUNET_MessageHeader *
+GNUNET_HELLO_get_header (struct GNUNET_HELLO_Message *hello);
+
+
+/**
+ * Helper function to load/access transport plugins.
+ * FIXME: pass closure!
+ *
+ * @param name name of the transport plugin to load
+ * @return NULL if a plugin with name @a name is not known/loadable
+ */
+typedef struct GNUNET_TRANSPORT_PluginFunctions *
+(*GNUNET_HELLO_TransportPluginsFind) (const char *name);
+
+
+/**
+ * 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);
+
+
+/**
+ * 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_get_id (const struct GNUNET_HELLO_Message *hello,
- struct GNUNET_PeerIdentity *peer);
+GNUNET_HELLO_parse_uri (const char *uri,
+ struct GNUNET_CRYPTO_EddsaPublicKey *pubkey,
+ struct GNUNET_HELLO_Message **hello,
+ GNUNET_HELLO_TransportPluginsFind plugins_find);
+
+
+#if 0 /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
/* ifndef GNUNET_HELLO_LIB_H */
#endif
+
+/** @} */ /* end of group */
+
/* end of gnunet_hello_lib.h */