X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fhello%2Fhello.c;h=e964ec1a3312d67f80e8c46ffc614570dbdcb7e8;hb=0778d7e951b20f42af01597ae41ba8d2d26857d0;hp=f41a601fd77d239330dd478ef554d81bfd3b20f8;hpb=537903a8dc4c3ecf2dfa382af0289ddf890adfc7;p=oweals%2Fgnunet.git diff --git a/src/hello/hello.c b/src/hello/hello.c index f41a601fd..e964ec1a3 100644 --- a/src/hello/hello.c +++ b/src/hello/hello.c @@ -4,7 +4,7 @@ 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 @@ -26,7 +26,10 @@ #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" + +GNUNET_NETWORK_STRUCT_BEGIN /** * A HELLO message is used to exchange information about @@ -37,66 +40,118 @@ * 1) transport-name (0-terminated) * 2) address-length (uint16_t, network byte order; possibly * unaligned!) - * 3) address expiration (GNUNET_TIME_AbsoluteNBO); possibly + * 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. + * Type will be #GNUNET_MESSAGE_TYPE_HELLO. */ struct GNUNET_MessageHeader header; /** - * Always zero (for alignment). + * Use in F2F mode: Do not gossip this HELLO message */ - uint32_t reserved GNUNET_PACKED; + uint32_t friend_only GNUNET_PACKED; /** * The public key of the peer. */ - struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded publicKey; + struct GNUNET_CRYPTO_EddsaPublicKey publicKey; + +}; +GNUNET_NETWORK_STRUCT_END + + +/** + * Context used for building our own URI. + */ +struct GNUNET_HELLO_ComposeUriContext +{ + /** + * Final URI. + */ + char *uri; + /** + * Function for finding transport plugins by name. + */ + 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; + + /** + * Set to #GNUNET_SYSERR to indicate parse errors. + */ + int ret; + + /** + * Function for finding transport plugins by name. + */ + GNUNET_HELLO_TransportPluginsFind plugins_find; +}; + + +/** Return HELLO type + * + * @param h HELLO Message to test + * @return #GNUNET_YES or #GNUNET_NO + */ +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, - struct GNUNET_TIME_Absolute expiration, - const void *addr, - uint16_t addr_len, char *target, size_t max) +GNUNET_HELLO_add_address (const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration, char *target, + size_t max) { uint16_t alen; size_t slen; struct GNUNET_TIME_AbsoluteNBO exp; - slen = strlen (tname) + 1; + slen = strlen (address->transport_name) + 1; if (slen + sizeof (uint16_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO) + - addr_len > max) + address->address_length > max) return 0; exp = GNUNET_TIME_absolute_hton (expiration); - alen = htons (addr_len); - memcpy (target, tname, slen); + alen = htons ((uint16_t) address->address_length); + memcpy (target, address->transport_name, slen); memcpy (&target[slen], &alen, sizeof (uint16_t)); slen += sizeof (uint16_t); memcpy (&target[slen], &exp, sizeof (struct GNUNET_TIME_AbsoluteNBO)); slen += sizeof (struct GNUNET_TIME_AbsoluteNBO); - memcpy (&target[slen], addr, addr_len); - slen += addr_len; + memcpy (&target[slen], address->address, address->address_length); + slen += address->address_length; return slen; } @@ -110,7 +165,9 @@ GNUNET_HELLO_add_address (const char *tname, * @return size of the entry, or 0 if max is not large enough */ static size_t -get_hello_address_size (const char *buf, size_t max, uint16_t * ralen) +get_hello_address_size (const char *buf, + size_t max, + uint16_t *ralen) { const char *pos; uint16_t alen; @@ -121,35 +178,34 @@ get_hello_address_size (const char *buf, size_t max, uint16_t * ralen) pos = buf; slen = 1; while ((left > 0) && ('\0' != *pos)) - { - left--; - pos++; - slen++; - } - if (left == 0) - { - /* 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 (uint16_t) + sizeof (struct GNUNET_TIME_AbsoluteNBO)) - { - /* not enough space for addrlen */ - GNUNET_break_op (0); - return 0; - } + { + /* not enough space for addrlen */ + GNUNET_break_op (0); + return 0; + } memcpy (&alen, pos, sizeof (uint16_t)); alen = ntohs (alen); *ralen = alen; 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; } @@ -162,10 +218,10 @@ get_hello_address_size (const char *buf, size_t max, uint16_t * ralen) * @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 *publicKey, GNUNET_HELLO_GenerateAddressListCallback addrgen, - void *addrgen_cls) + void *addrgen_cls, + int friend_only) { char buffer[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1 - 256 - sizeof (struct GNUNET_HELLO_Message)]; @@ -174,21 +230,26 @@ GNUNET_HELLO_create (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded size_t ret; struct GNUNET_HELLO_Message *hello; + GNUNET_assert (NULL != publicKey); + GNUNET_assert ((GNUNET_YES == friend_only) || (GNUNET_NO == friend_only)); + max = sizeof (buffer); used = 0; if (addrgen != NULL) + { + while (0 != (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); + hello->friend_only = htonl (friend_only); + memcpy (&hello->publicKey, publicKey, - sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded)); + sizeof (struct GNUNET_CRYPTO_EddsaPublicKey)); memcpy (&hello[1], buffer, used); return hello; } @@ -201,13 +262,15 @@ 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) { + struct GNUNET_HELLO_Address address; uint16_t msize; struct GNUNET_HELLO_Message *ret; const char *inptr; @@ -225,46 +288,47 @@ GNUNET_HELLO_iterate_addresses (const struct GNUNET_HELLO_Message *msg, return NULL; ret = NULL; if (return_modified) - { - ret = GNUNET_malloc (msize); - memcpy (ret, msg, msize); - } + { + ret = GNUNET_malloc (msize); + 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; + address.peer.public_key = msg->publicKey; while (insize > 0) + { + esize = get_hello_address_size (inptr, insize, &alen); + if (0 == esize) + { + 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)); + 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 (iret == GNUNET_SYSERR) { - 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; + 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; + } if (ret != NULL) ret->header.size = ntohs (sizeof (struct GNUNET_HELLO_Message) + wpos); return ret; @@ -273,30 +337,24 @@ GNUNET_HELLO_iterate_addresses (const struct GNUNET_HELLO_Message *msg, struct ExpireContext { - const void *addr; - const char *tname; - uint16_t addrlen; + const struct GNUNET_HELLO_Address *address; int found; struct GNUNET_TIME_Absolute expiration; }; static int -get_match_exp (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, uint16_t addrlen) +get_match_exp (void *cls, 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 */ - } + if (0 == GNUNET_HELLO_address_cmp (address, ec->address)) + { + ec->found = GNUNET_YES; + ec->expiration = expiration; + return GNUNET_SYSERR; /* done here */ + } return GNUNET_OK; } @@ -315,31 +373,24 @@ struct MergeContext static int -copy_latest (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, uint16_t addrlen) +copy_latest (void *cls, 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); - } + if ((ec.found == GNUNET_NO) || + (ec.expiration.abs_value_us < expiration.abs_value_us) || + ((ec.expiration.abs_value_us == expiration.abs_value_us) && + (mc->take_equal == GNUNET_YES))) + { + mc->ret += + GNUNET_HELLO_add_address (address, expiration, &mc->buf[mc->ret], + mc->max - mc->ret); + } return GNUNET_OK; } @@ -379,8 +430,14 @@ 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; + + 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); + return GNUNET_HELLO_create (&h1->publicKey, &merge_addr, &mc, friend_only); } @@ -397,26 +454,22 @@ struct DeltaContext static int -delta_match (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, uint16_t addrlen) +delta_match (void *cls, 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); + 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))) + ((ec.expiration.abs_value_us > expiration.abs_value_us) || + (ec.expiration.abs_value_us >= dc->expiration_limit.abs_value_us))) return GNUNET_YES; /* skip */ - ret = dc->it (dc->it_cls, tname, expiration, addr, addrlen); + ret = dc->it (dc->it_cls, address, expiration); return ret; } @@ -461,6 +514,7 @@ 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; @@ -477,10 +531,10 @@ GNUNET_HELLO_size (const struct GNUNET_HELLO_Message *hello) */ int GNUNET_HELLO_get_key (const struct GNUNET_HELLO_Message *hello, - struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded - *publicKey) + struct GNUNET_CRYPTO_EddsaPublicKey *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; @@ -494,19 +548,18 @@ GNUNET_HELLO_get_key (const struct GNUNET_HELLO_Message *hello, * * @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; } @@ -523,6 +576,7 @@ 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; @@ -538,74 +592,56 @@ struct EqualsContext struct GNUNET_TIME_Absolute result; const struct GNUNET_HELLO_Message *h2; - - const char *tname; - - const void *addr; - + + const struct GNUNET_HELLO_Address *address; + struct GNUNET_TIME_Absolute expiration; int found; - uint16_t addrlen; - }; static int -find_other_matching (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, uint16_t addrlen) +find_other_matching (void *cls, const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) { struct EqualsContext *ec = cls; - if (expiration.value < ec->expiration_limit.value) + if (expiration.abs_value_us < ec->expiration_limit.abs_value_us) return GNUNET_YES; - if ( (addrlen == ec->addrlen) && - (0 == strcmp (tname, - ec->tname)) && - (0 == memcmp (addr, - ec->addr, - addrlen)) ) - { - ec->found = GNUNET_YES; - if (expiration.value < ec->expiration.value) - ec->result = GNUNET_TIME_absolute_min (expiration, - ec->result); - return GNUNET_SYSERR; - } + 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; } static int -find_matching (void *cls, - const char *tname, - struct GNUNET_TIME_Absolute expiration, - const void *addr, uint16_t addrlen) +find_matching (void *cls, const struct GNUNET_HELLO_Address *address, + struct GNUNET_TIME_Absolute expiration) { struct EqualsContext *ec = cls; - if (expiration.value < ec->expiration_limit.value) + if (expiration.abs_value_us < ec->expiration_limit.abs_value_us) return GNUNET_YES; - ec->tname = tname; + ec->address = address; ec->expiration = expiration; - ec->addr = addr; - ec->addrlen = addrlen; ec->found = GNUNET_NO; - GNUNET_HELLO_iterate_addresses (ec->h2, - GNUNET_NO, - &find_other_matching, - ec); + GNUNET_HELLO_iterate_addresses (ec->h2, GNUNET_NO, &find_other_matching, ec); if (ec->found == GNUNET_NO) - { - ec->result = GNUNET_TIME_UNIT_ZERO_ABS; - return GNUNET_SYSERR; - } + { + 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 @@ -616,42 +652,440 @@ find_matching (void *cls, * @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 + * @return absolute time forever if the two HELLOs are * totally identical; smallest timestamp >= now if - * they only differ in timestamps; + * 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) +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 (0 != memcmp (&h1->publicKey, - &h2->publicKey, - sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded))) + 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.h2 = h2; - GNUNET_HELLO_iterate_addresses (h1, - GNUNET_NO, - &find_matching, - &ec); - if (ec.result.value == - GNUNET_TIME_UNIT_ZERO.value) - return ec.result; + 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.h2 = h1; - GNUNET_HELLO_iterate_addresses (h2, - GNUNET_NO, - &find_matching, - &ec); + GNUNET_HELLO_iterate_addresses (h2, GNUNET_NO, &find_matching, &ec); return ec.result; } +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.abs_value_us = 0; + 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!!

]...". + * These URIs can be used to add a peer record to peerinfo service. + * PEER is the string representation of peer's public key. + * YYYYMMDDHHMMSS is the expiration date. + * TYPE is a transport type. + * ADDRESS is the address, its format depends upon the transport type. + * The concrete transport types and corresponding address formats are: + * + * + * + * The encoding for hexadecimal values is defined in the crypto_hash.c + * module in the gnunetutil library and discussed there. + * + * Examples: + * + * gnunet://hello/0430205UC7D56PTQK8NV05776671CNN44FK4TL6D0GQ35OMF8MEN4RNMKA5UF6AL3DQO8B1SC5AQF50SQ2MABIRU4HC8H2HAJKJ59JL1JVRJAK308F9GASRFLMGUBB5TQ5AKR94AS5T3MDG8B9O1EMPRKB0HVCG7T6QPP4CDJ913LAEHVJ2DI1TOBB15Q1JIT5ARBOD12U4SIGRFDV3Q7T66G4TBVSJJ90UQF1BG29TGJJKLGEIMSPHHKO544D6EALQ4F2K0416311JC22GVAD48R616I7VK03K7MP7N0RS2MBV1TE9JV8CK1LSQMR7KCDRTLDA6917UGA67DHTGHERIACCGQ54TGSR48RMSGS9BA5HLMOKASFC1I6V4TT09TUGCU8GNDHQF0JF3H7LPV59UL5I38QID040G000!20120302010059!TCP!192.168.0.1:2086!TCP!64.23.8.174:0 + * gnunet://hello/0430205UC7D56PTQK8NV05776671CNN44FK4TL6D0GQ35OMF8MEN4RNMKA5UF6AL3DQO8B1SC5AQF50SQ2MABIRU4HC8H2HAJKJ59JL1JVRJAK308F9GASRFLMGUBB5TQ5AKR94AS5T3MDG8B9O1EMPRKB0HVCG7T6QPP4CDJ913LAEHVJ2DI1TOBB15Q1JIT5ARBOD12U4SIGRFDV3Q7T66G4TBVSJJ90UQF1BG29TGJJKLGEIMSPHHKO544D6EALQ4F2K0416311JC22GVAD48R616I7VK03K7MP7N0RS2MBV1TE9JV8CK1LSQMR7KCDRTLDA6917UGA67DHTGHERIACCGQ54TGSR48RMSGS9BA5HLMOKASFC1I6V4TT09TUGCU8GNDHQF0JF3H7LPV59UL5I38QID040G000!20120302010059!TCP!(2001:db8:85a3:8d3:1319:8a2e:370:7348):2086 + * + *

+ */ + + +/* ************************* Compose HELLO URI ************************** */ + + +/** + * Replace all characters in the input 'in' according + * to the mapping. The mapping says to map each character + * in 'oldchars' to the corresponding character (by offset) + * in 'newchars'. + * + * @param in input string to remap + * @param oldchars characters to replace + * @param newchars replacement characters, must have same length as 'oldchars' + * @return copy of string with replacement applied. + */ +static char * +map_characters (const char *in, + const char *oldchars, + const char *newchars) +{ + char *ret; + const char *off; + size_t i; + + GNUNET_assert (strlen (oldchars) == strlen (newchars)); + ret = GNUNET_strdup (in); + i = 0; + while (ret[i] != '\0') + { + off = strchr (oldchars, ret[i]); + if (NULL != off) + ret[i] = newchars[off - oldchars]; + i++; + } + return ret; +} + + +/** + * Function that is called on each address of this peer. + * Expands the corresponding URI string. + * + * @param cls the 'GNUNET_HELLO_GetUriContext' + * @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 *uri_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 (papi == NULL) + { + /* 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 ( (addr == NULL) || (strlen(addr) == 0) ) + return GNUNET_OK; + + addr_dup = GNUNET_strdup (addr); + if (NULL != (pos = strstr (addr_dup, "_server"))) + memcpy (pos, client_str, strlen(client_str)); /* Replace all server addresses with client addresses */ + + /* For URIs we use '(' and ')' instead of '[' and ']' as brackets are reserved + characters in URIs */ + uri_addr = map_characters (addr_dup, "[]", "()"); + GNUNET_free (addr_dup); + seconds = expiration.abs_value_us / 1000LL / 1000LL; + t = gmtime (&seconds); + + GNUNET_asprintf (&ret, + "%s!%s!%s!%s", + ctx->uri, + strftime (tbuf, sizeof (tbuf), "%Y%m%d%H%M%S", t) ? tbuf : "0", + address->transport_name, + uri_addr); + GNUNET_free (uri_addr); + 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; + ctx.plugins_find = plugins_find; + + char *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_AddressParsingContext' + * @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 + */ +static size_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; + char *plugin_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; + size_t ret; + + if (NULL == ctx->pos) + return 0; + if ('!' != ctx->pos[0]) + { + ctx->ret = GNUNET_SYSERR; + GNUNET_break (0); + return 0; + } + ctx->pos++; + + if ('0' == ctx->pos[0] && '!' == 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 0; + } + + 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 0; + } + expire.abs_value_us = expiration_seconds * 1000LL * 1000LL; + } + if ('!' != tname[0]) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("Failed to parse HELLO message: malformed\n")); + ctx->ret = GNUNET_SYSERR; + GNUNET_break (0); + return 0; + } + tname++; + address = strchr (tname, (int) '!'); + 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 0; + } + address++; + end = strchr (address, (int) '!'); + ctx->pos = end; + 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_ERROR, + _("Plugin `%s' not found\n"), + plugin_name); + GNUNET_free (plugin_name); + GNUNET_break (0); + return 0; + } + if (NULL == papi->string_to_address) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("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); + /* For URIs we use '(' and ')' instead of '[' and ']' as brackets are reserved + characters in URIs; need to convert back to '[]' for the plugin */ + plugin_address = map_characters (uri_address, "()", "[]"); + GNUNET_free (uri_address); + if (GNUNET_OK != + papi->string_to_address (papi->cls, + plugin_address, + strlen (plugin_address) + 1, + &addr, + &addr_len)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("Failed to parse `%s' as an address for plugin `%s'\n"), + plugin_address, + plugin_name); + GNUNET_free (plugin_name); + GNUNET_free (plugin_address); + return 0; + } + GNUNET_free (plugin_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); + 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 = strstr (pks, "!"); + + 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.plugins_find = plugins_find; + *hello = GNUNET_HELLO_create (pubkey, &add_address_to_hello, &ctx, friend_only); + + return ctx.ret; +} + + /* end of hello.c */