123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412 |
- /*
- This file is part of GNUnet
- Copyright (C) 2013 GNUnet e.V.
- GNUnet is free software: you can redistribute it and/or modify it
- under the terms of the GNU Affero General Public License as published
- by the Free Software Foundation, either version 3 of the License,
- or (at your option) any later version.
- GNUnet is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Affero General Public License for more details.
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- SPDX-License-Identifier: AGPL3.0-or-later
- */
- /**
- * @file regex/plugin_block_regex.c
- * @brief blocks used for regex storage and search
- * @author Bartlomiej Polot
- */
- #include "platform.h"
- #include "gnunet_block_plugin.h"
- #include "gnunet_block_group_lib.h"
- #include "block_regex.h"
- #include "regex_block_lib.h"
- #include "gnunet_signatures.h"
- /**
- * Number of bits we set per entry in the bloomfilter.
- * Do not change!
- */
- #define BLOOMFILTER_K 16
- /**
- * How big is the BF we use for REGEX blocks?
- */
- #define REGEX_BF_SIZE 8
- /**
- * Create a new block group.
- *
- * @param ctx block context in which the block group is created
- * @param type type of the block for which we are creating the group
- * @param nonce random value used to seed the group creation
- * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
- * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
- * @param va variable arguments specific to @a type
- * @return block group handle, NULL if block groups are not supported
- * by this @a type of block (this is not an error)
- */
- static struct GNUNET_BLOCK_Group *
- block_plugin_regex_create_group (void *cls,
- enum GNUNET_BLOCK_Type type,
- uint32_t nonce,
- const void *raw_data,
- size_t raw_data_size,
- va_list va)
- {
- unsigned int bf_size;
- const char *guard;
- guard = va_arg (va, const char *);
- if (0 == strcmp (guard,
- "seen-set-size"))
- bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned
- int),
- BLOOMFILTER_K);
- else if (0 == strcmp (guard,
- "filter-size"))
- bf_size = va_arg (va, unsigned int);
- else
- {
- GNUNET_break (0);
- bf_size = REGEX_BF_SIZE;
- }
- GNUNET_break (NULL == va_arg (va, const char *));
- return GNUNET_BLOCK_GROUP_bf_create (cls,
- bf_size,
- BLOOMFILTER_K,
- type,
- nonce,
- raw_data,
- raw_data_size);
- }
- /**
- * Function called to validate a reply or a request of type
- * #GNUNET_BLOCK_TYPE_REGEX.
- * For request evaluation, pass "NULL" for the reply_block.
- * Note that it is assumed that the reply has already been
- * matched to the key (and signatures checked) as it would
- * be done with the #GNUNET_BLOCK_get_key() function.
- *
- * @param cls closure
- * @param type block type
- * @param bg block group to evaluate against
- * @param eo control flags
- * @param query original query (hash)
- * @param xquery extrended query data (can be NULL, depending on type)
- * @param xquery_size number of bytes in @a xquery
- * @param reply_block response to validate
- * @param reply_block_size number of bytes in @a reply_block
- * @return characterization of result
- */
- static enum GNUNET_BLOCK_EvaluationResult
- evaluate_block_regex (void *cls,
- enum GNUNET_BLOCK_Type type,
- struct GNUNET_BLOCK_Group *bg,
- enum GNUNET_BLOCK_EvaluationOptions eo,
- const struct GNUNET_HashCode *query,
- const void *xquery,
- size_t xquery_size,
- const void *reply_block,
- size_t reply_block_size)
- {
- struct GNUNET_HashCode chash;
- if (NULL == reply_block)
- {
- if (0 != xquery_size)
- {
- const char *s;
- s = (const char *) xquery;
- if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
- }
- }
- return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
- }
- if (0 != xquery_size)
- {
- const char *s;
- s = (const char *) xquery;
- if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
- }
- }
- else if (NULL != query)
- {
- /* xquery is required for regex GETs, at least an empty string */
- GNUNET_break_op (0);
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "type %d, query %p, xquery %p\n",
- type, query, xquery);
- return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
- }
- switch (REGEX_BLOCK_check (reply_block,
- reply_block_size,
- query,
- xquery))
- {
- case GNUNET_SYSERR:
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
- case GNUNET_NO:
- /* xquery mismatch, can happen */
- return GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT;
- default:
- break;
- }
- GNUNET_CRYPTO_hash (reply_block,
- reply_block_size,
- &chash);
- if (GNUNET_YES ==
- GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
- &chash))
- return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
- return GNUNET_BLOCK_EVALUATION_OK_MORE;
- }
- /**
- * Function called to validate a reply or a request of type
- * #GNUNET_BLOCK_TYPE_REGEX_ACCEPT.
- * For request evaluation, pass "NULL" for the reply_block.
- * Note that it is assumed that the reply has already been
- * matched to the key (and signatures checked) as it would
- * be done with the #GNUNET_BLOCK_get_key() function.
- *
- * @param cls closure
- * @param type block type
- * @param bg block group to evaluate against
- * @param eo control flags
- * @param query original query (hash)
- * @param xquery extrended query data (can be NULL, depending on type)
- * @param xquery_size number of bytes in @a xquery
- * @param reply_block response to validate
- * @param reply_block_size number of bytes in @a reply_block
- * @return characterization of result
- */
- static enum GNUNET_BLOCK_EvaluationResult
- evaluate_block_regex_accept (void *cls,
- enum GNUNET_BLOCK_Type type,
- struct GNUNET_BLOCK_Group *bg,
- enum GNUNET_BLOCK_EvaluationOptions eo,
- const struct GNUNET_HashCode *query,
- const void *xquery,
- size_t xquery_size, const void *reply_block,
- size_t reply_block_size)
- {
- const struct RegexAcceptBlock *rba;
- struct GNUNET_HashCode chash;
- if (0 != xquery_size)
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
- }
- if (NULL == reply_block)
- return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
- if (sizeof(struct RegexAcceptBlock) != reply_block_size)
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
- }
- rba = reply_block;
- if (ntohl (rba->purpose.size) !=
- sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose)
- + sizeof(struct GNUNET_TIME_AbsoluteNBO)
- + sizeof(struct GNUNET_HashCode))
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
- }
- if (0 == GNUNET_TIME_absolute_get_remaining (GNUNET_TIME_absolute_ntoh (
- rba->expiration_time)).
- rel_value_us)
- {
- /* technically invalid, but can happen without an error, so
- we're nice by reporting it as a 'duplicate' */
- return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
- }
- if (GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify_ (GNUNET_SIGNATURE_PURPOSE_REGEX_ACCEPT,
- &rba->purpose,
- &rba->signature,
- &rba->peer.public_key))
- {
- GNUNET_break_op (0);
- return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
- }
- GNUNET_CRYPTO_hash (reply_block,
- reply_block_size,
- &chash);
- if (GNUNET_YES ==
- GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
- &chash))
- return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
- return GNUNET_BLOCK_EVALUATION_OK_MORE;
- }
- /**
- * Function called to validate a reply or a request. For
- * request evaluation, simply pass "NULL" for the reply_block.
- * Note that it is assumed that the reply has already been
- * matched to the key (and signatures checked) as it would
- * be done with the #GNUNET_BLOCK_get_key() function.
- *
- * @param cls closure
- * @param ctx block context
- * @param type block type
- * @param bg group to evaluate against
- * @param eo control flags
- * @param query original query (hash)
- * @param xquery extrended query data (can be NULL, depending on type)
- * @param xquery_size number of bytes in xquery
- * @param reply_block response to validate
- * @param reply_block_size number of bytes in reply block
- * @return characterization of result
- */
- static enum GNUNET_BLOCK_EvaluationResult
- block_plugin_regex_evaluate (void *cls,
- struct GNUNET_BLOCK_Context *ctx,
- enum GNUNET_BLOCK_Type type,
- struct GNUNET_BLOCK_Group *bg,
- enum GNUNET_BLOCK_EvaluationOptions eo,
- const struct GNUNET_HashCode *query,
- const void *xquery,
- size_t xquery_size,
- const void *reply_block,
- size_t reply_block_size)
- {
- enum GNUNET_BLOCK_EvaluationResult result;
- switch (type)
- {
- case GNUNET_BLOCK_TYPE_REGEX:
- result = evaluate_block_regex (cls,
- type,
- bg,
- eo,
- query,
- xquery, xquery_size,
- reply_block, reply_block_size);
- break;
- case GNUNET_BLOCK_TYPE_REGEX_ACCEPT:
- result = evaluate_block_regex_accept (cls,
- type,
- bg,
- eo,
- query,
- xquery, xquery_size,
- reply_block, reply_block_size);
- break;
- default:
- result = GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
- }
- return result;
- }
- /**
- * Function called to obtain the key for a block.
- *
- * @param cls closure
- * @param type block type
- * @param block block to get the key for
- * @param block_size number of bytes in @a block
- * @param key set to the key (query) for the given block
- * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
- * (or if extracting a key from a block of this type does not work)
- */
- static int
- block_plugin_regex_get_key (void *cls,
- enum GNUNET_BLOCK_Type type,
- const void *block,
- size_t block_size,
- struct GNUNET_HashCode *key)
- {
- switch (type)
- {
- case GNUNET_BLOCK_TYPE_REGEX:
- if (GNUNET_OK !=
- REGEX_BLOCK_get_key (block, block_size,
- key))
- {
- GNUNET_break_op (0);
- return GNUNET_NO;
- }
- return GNUNET_OK;
- case GNUNET_BLOCK_TYPE_REGEX_ACCEPT:
- if (sizeof(struct RegexAcceptBlock) != block_size)
- {
- GNUNET_break_op (0);
- return GNUNET_NO;
- }
- *key = ((struct RegexAcceptBlock *) block)->key;
- return GNUNET_OK;
- default:
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- }
- /**
- * Entry point for the plugin.
- */
- void *
- libgnunet_plugin_block_regex_init (void *cls)
- {
- static enum GNUNET_BLOCK_Type types[] = {
- GNUNET_BLOCK_TYPE_REGEX,
- GNUNET_BLOCK_TYPE_REGEX_ACCEPT,
- GNUNET_BLOCK_TYPE_ANY /* end of list */
- };
- struct GNUNET_BLOCK_PluginFunctions *api;
- api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
- api->evaluate = &block_plugin_regex_evaluate;
- api->get_key = &block_plugin_regex_get_key;
- api->create_group = &block_plugin_regex_create_group;
- api->types = types;
- return api;
- }
- /**
- * Exit point from the plugin.
- */
- void *
- libgnunet_plugin_block_regex_done (void *cls)
- {
- struct GNUNET_BLOCK_PluginFunctions *api = cls;
- GNUNET_free (api);
- return NULL;
- }
- /* end of plugin_block_regex.c */
|