/* This file is part of GNUnet (C) 2003, 2004, 2005, 2006, 2007, 2008 Christian Grothoff (and other contributing authors) 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 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 General Public License for more details. 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. */ /** * @file util/pseudonym.c * @brief helper functions * @author Christian Grothoff */ #include "platform.h" #include "gnunet_common.h" #include "gnunet_container_lib.h" #include "gnunet_disk_lib.h" #include "gnunet_pseudonym_lib.h" #include "gnunet_bio_lib.h" #define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__) #define LOG_STRERROR_FILE(kind,syscall,filename) GNUNET_log_from_strerror_file (kind, "util", syscall, filename) /** * Name of the directory which stores meta data for pseudonym */ #define PS_METADATA_DIR DIR_SEPARATOR_STR "data" DIR_SEPARATOR_STR "pseudonyms" DIR_SEPARATOR_STR "metadata" DIR_SEPARATOR_STR /** * Name of the directory which stores names for pseudonyms */ #define PS_NAMES_DIR DIR_SEPARATOR_STR "data" DIR_SEPARATOR_STR "pseudonyms" DIR_SEPARATOR_STR "names" DIR_SEPARATOR_STR /** * Configuration section we use. */ #define GNUNET_CLIENT_SERVICE_NAME "client" /** * Registered callbacks for discovery of pseudonyms. */ struct DiscoveryCallback { /** * This is a linked list. */ struct DiscoveryCallback *next; /** * Function to call each time a pseudonym is discovered. */ GNUNET_PSEUDONYM_Iterator callback; /** * Closure for callback. */ void *closure; }; /** * Head of the linked list of functions to call when * new pseudonyms are added. */ static struct DiscoveryCallback *head; /** * Internal notification about new tracked URI. * @param id a point to the hash code of pseudonym * @param md meta data to be written * @param rating rating of pseudonym */ static void internal_notify (const struct GNUNET_HashCode * id, const struct GNUNET_CONTAINER_MetaData *md, int rating) { struct DiscoveryCallback *pos; pos = head; while (pos != NULL) { pos->callback (pos->closure, id, NULL, NULL, md, rating); pos = pos->next; } } /** * Register callback to be invoked whenever we discover * a new pseudonym. * Will immediately call provided iterator callback for all * already discovered pseudonyms. * * @param cfg configuration to use * @param iterator iterator over pseudonym * @param closure point to a closure */ int GNUNET_PSEUDONYM_discovery_callback_register (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_PSEUDONYM_Iterator iterator, void *closure) { struct DiscoveryCallback *list; list = GNUNET_malloc (sizeof (struct DiscoveryCallback)); list->callback = iterator; list->closure = closure; list->next = head; head = list; GNUNET_PSEUDONYM_list_all (cfg, iterator, closure); return GNUNET_OK; } /** * Unregister pseudonym discovery callback. * @param iterator iterator over pseudonym * @param closure point to a closure */ int GNUNET_PSEUDONYM_discovery_callback_unregister (GNUNET_PSEUDONYM_Iterator iterator, void *closure) { struct DiscoveryCallback *prev; struct DiscoveryCallback *pos; prev = NULL; pos = head; while ((pos != NULL) && ((pos->callback != iterator) || (pos->closure != closure))) { prev = pos; pos = pos->next; } if (pos == NULL) return GNUNET_SYSERR; if (prev == NULL) head = pos->next; else prev->next = pos->next; GNUNET_free (pos); return GNUNET_OK; } /** * Get the filename (or directory name) for the given * pseudonym identifier and directory prefix. * @param cfg configuration to use * @param prefix path components to append to the private directory name * @param psid hash code of pseudonym, can be NULL * @return filename of the pseudonym (if psid != NULL) or directory with the data (if psid == NULL) */ static char * get_data_filename (const struct GNUNET_CONFIGURATION_Handle *cfg, const char *prefix, const struct GNUNET_HashCode * psid) { struct GNUNET_CRYPTO_HashAsciiEncoded enc; if (psid != NULL) GNUNET_CRYPTO_hash_to_enc (psid, &enc); return GNUNET_DISK_get_home_filename (cfg, GNUNET_CLIENT_SERVICE_NAME, prefix, (psid == NULL) ? NULL : (const char *) &enc, NULL); } /** * Write the pseudonym infomation into a file * @param cfg configuration to use * @param nsid hash code of a pseudonym * @param meta meta data to be written into a file * @param ranking ranking of a pseudonym * @param ns_name non-unique name of a pseudonym */ static void write_pseudonym_info (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, const struct GNUNET_CONTAINER_MetaData *meta, int32_t ranking, const char *ns_name) { char *fn; struct GNUNET_BIO_WriteHandle *fileW; fn = get_data_filename (cfg, PS_METADATA_DIR, nsid); GNUNET_assert (fn != NULL); fileW = GNUNET_BIO_write_open (fn); if (NULL != fileW) { if ((GNUNET_OK != GNUNET_BIO_write_int32 (fileW, ranking)) || (GNUNET_OK != GNUNET_BIO_write_string (fileW, ns_name)) || (GNUNET_OK != GNUNET_BIO_write_meta_data (fileW, meta))) { (void) GNUNET_BIO_write_close (fileW); GNUNET_break (GNUNET_OK == GNUNET_DISK_directory_remove (fn)); GNUNET_free (fn); return; } if (GNUNET_OK != GNUNET_BIO_write_close (fileW)) { GNUNET_break (GNUNET_OK == GNUNET_DISK_directory_remove (fn)); GNUNET_free (fn); return; } } GNUNET_free (fn); /* create entry for pseudonym name in names */ if (ns_name != NULL) GNUNET_free_non_null (GNUNET_PSEUDONYM_name_uniquify (cfg, nsid, ns_name, NULL)); } /** * read the pseudonym infomation from a file * @param cfg configuration to use * @param nsid hash code of a pseudonym * @param meta meta data to be read from a file * @param ranking ranking of a pseudonym * @param ns_name name of a pseudonym */ static int read_info (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, struct GNUNET_CONTAINER_MetaData **meta, int32_t * ranking, char **ns_name) { char *fn; char *emsg; struct GNUNET_BIO_ReadHandle *fileR; fn = get_data_filename (cfg, PS_METADATA_DIR, nsid); GNUNET_assert (fn != NULL); fileR = GNUNET_BIO_read_open (fn); if (fileR == NULL) { GNUNET_free (fn); return GNUNET_SYSERR; } emsg = NULL; *ns_name = NULL; if ((GNUNET_OK != GNUNET_BIO_read_int32 (fileR, ranking)) || (GNUNET_OK != GNUNET_BIO_read_string (fileR, "Read string error!", ns_name, 200)) || (GNUNET_OK != GNUNET_BIO_read_meta_data (fileR, "Read meta data error!", meta))) { (void) GNUNET_BIO_read_close (fileR, &emsg); GNUNET_free_non_null (emsg); GNUNET_free_non_null (*ns_name); *ns_name = NULL; GNUNET_break (GNUNET_OK == GNUNET_DISK_directory_remove (fn)); GNUNET_free (fn); return GNUNET_SYSERR; } if (GNUNET_OK != GNUNET_BIO_read_close (fileR, &emsg)) { LOG (GNUNET_ERROR_TYPE_WARNING, _("Failed to parse metadata about pseudonym from file `%s': %s\n"), fn, emsg); GNUNET_break (GNUNET_OK == GNUNET_DISK_directory_remove (fn)); GNUNET_CONTAINER_meta_data_destroy (*meta); *meta = NULL; GNUNET_free_non_null (*ns_name); *ns_name = NULL; GNUNET_free_non_null (emsg); GNUNET_free (fn); return GNUNET_SYSERR; } GNUNET_free (fn); return GNUNET_OK; } /** * Return unique variant of the namespace name. * Use it after GNUNET_PSEUDONYM_get_info() to make sure * that name is unique. * * @param cfg configuration * @param nsid cryptographic ID of the namespace * @param name name to uniquify * @param suffix if not NULL, filled with the suffix value * @return NULL on failure (should never happen), name on success. * Free the name with GNUNET_free(). */ char * GNUNET_PSEUDONYM_name_uniquify (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, const char *name, unsigned int *suffix) { struct GNUNET_HashCode nh; uint64_t len; char *fn; struct GNUNET_DISK_FileHandle *fh; unsigned int i; unsigned int idx; char *ret; struct stat sbuf; GNUNET_CRYPTO_hash (name, strlen (name), &nh); fn = get_data_filename (cfg, PS_NAMES_DIR, &nh); GNUNET_assert (fn != NULL); len = 0; if (0 == STAT (fn, &sbuf)) GNUNET_break (GNUNET_OK == GNUNET_DISK_file_size (fn, &len, GNUNET_YES, GNUNET_YES)); fh = GNUNET_DISK_file_open (fn, GNUNET_DISK_OPEN_CREATE | GNUNET_DISK_OPEN_READWRITE, GNUNET_DISK_PERM_USER_READ | GNUNET_DISK_PERM_USER_WRITE); i = 0; idx = -1; while ((len >= sizeof (struct GNUNET_HashCode)) && (sizeof (struct GNUNET_HashCode) == GNUNET_DISK_file_read (fh, &nh, sizeof (struct GNUNET_HashCode)))) { if (0 == memcmp (&nh, nsid, sizeof (struct GNUNET_HashCode))) { idx = i; break; } i++; len -= sizeof (struct GNUNET_HashCode); } if (idx == -1) { idx = i; if (sizeof (struct GNUNET_HashCode) != GNUNET_DISK_file_write (fh, nsid, sizeof (struct GNUNET_HashCode))) LOG_STRERROR_FILE (GNUNET_ERROR_TYPE_WARNING, "write", fn); } GNUNET_DISK_file_close (fh); ret = GNUNET_malloc (strlen (name) + 32); GNUNET_snprintf (ret, strlen (name) + 32, "%s-%u", name, idx); if (suffix != NULL) *suffix = idx; GNUNET_free (fn); return ret; } /** * Get namespace name, metadata and rank * This is a wrapper around internal read_info() call, and ensures that * returned data is not invalid (not NULL). * * @param cfg configuration * @param nsid cryptographic ID of the namespace * @param ret_meta a location to store metadata pointer. NULL, if metadata * is not needed. Destroy with GNUNET_CONTAINER_meta_data_destroy(). * @param ret_rank a location to store rank. NULL, if rank not needed. * @param ret_name a location to store human-readable name. Name is not unique. * NULL, if name is not needed. Free with GNUNET_free(). * @param name_is_a_dup is set to GNUNET_YES, if ret_name was filled with * a duplicate of a "no-name" placeholder * @return GNUNET_OK on success. GNUENT_SYSERR if the data was * unobtainable (in that case ret_* are filled with placeholders - * empty metadata container, rank -1 and a "no-name" name). */ int GNUNET_PSEUDONYM_get_info (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, struct GNUNET_CONTAINER_MetaData **ret_meta, int32_t *ret_rank, char **ret_name, int *name_is_a_dup) { struct GNUNET_CONTAINER_MetaData *meta; char *name; int32_t rank = -1; meta = NULL; name = NULL; if (GNUNET_OK == read_info (cfg, nsid, &meta, &rank, &name)) { if ((meta != NULL) && (name == NULL)) name = GNUNET_CONTAINER_meta_data_get_first_by_types (meta, EXTRACTOR_METATYPE_TITLE, EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME, EXTRACTOR_METATYPE_FILENAME, EXTRACTOR_METATYPE_DESCRIPTION, EXTRACTOR_METATYPE_SUBJECT, EXTRACTOR_METATYPE_PUBLISHER, EXTRACTOR_METATYPE_AUTHOR_NAME, EXTRACTOR_METATYPE_COMMENT, EXTRACTOR_METATYPE_SUMMARY, -1); if (ret_name != NULL) { if (name == NULL) { name = GNUNET_strdup (_("no-name")); if (name_is_a_dup != NULL) *name_is_a_dup = GNUNET_YES; } else if (name_is_a_dup != NULL) *name_is_a_dup = GNUNET_NO; *ret_name = name; } else if (name != NULL) GNUNET_free (name); if (ret_meta != NULL) { if (meta == NULL) meta = GNUNET_CONTAINER_meta_data_create (); *ret_meta = meta; } else if (meta != NULL) GNUNET_CONTAINER_meta_data_destroy (meta); if (ret_rank != NULL) *ret_rank = rank; return GNUNET_OK; } if (ret_name != NULL) *ret_name = GNUNET_strdup (_("no-name")); if (ret_meta != NULL) *ret_meta = GNUNET_CONTAINER_meta_data_create (); if (ret_rank != NULL) *ret_rank = -1; if (name_is_a_dup != NULL) *name_is_a_dup = GNUNET_YES; return GNUNET_SYSERR; } /** * Get the namespace ID belonging to the given namespace name. * * @param cfg configuration to use * @param ns_uname unique (!) human-readable name for the namespace * @param nsid set to namespace ID based on 'ns_uname' * @return GNUNET_OK on success, GNUNET_SYSERR on failure */ int GNUNET_PSEUDONYM_name_to_id (const struct GNUNET_CONFIGURATION_Handle *cfg, const char *ns_uname, struct GNUNET_HashCode * nsid) { size_t slen; uint64_t len; unsigned int idx; char *name; struct GNUNET_HashCode nh; char *fn; struct GNUNET_DISK_FileHandle *fh; idx = -1; slen = strlen (ns_uname); while ((slen > 0) && (1 != SSCANF (&ns_uname[slen - 1], "-%u", &idx))) slen--; if (slen == 0) return GNUNET_SYSERR; name = GNUNET_strdup (ns_uname); name[slen - 1] = '\0'; GNUNET_CRYPTO_hash (name, strlen (name), &nh); GNUNET_free (name); fn = get_data_filename (cfg, PS_NAMES_DIR, &nh); GNUNET_assert (fn != NULL); if ((GNUNET_OK != GNUNET_DISK_file_test (fn) || (GNUNET_OK != GNUNET_DISK_file_size (fn, &len, GNUNET_YES, GNUNET_YES))) || ((idx + 1) * sizeof (struct GNUNET_HashCode) > len)) { GNUNET_free (fn); return GNUNET_SYSERR; } fh = GNUNET_DISK_file_open (fn, GNUNET_DISK_OPEN_CREATE | GNUNET_DISK_OPEN_READWRITE, GNUNET_DISK_PERM_USER_READ | GNUNET_DISK_PERM_USER_WRITE); GNUNET_free (fn); if (GNUNET_SYSERR == GNUNET_DISK_file_seek (fh, idx * sizeof (struct GNUNET_HashCode), GNUNET_DISK_SEEK_SET)) { GNUNET_DISK_file_close (fh); return GNUNET_SYSERR; } if (sizeof (struct GNUNET_HashCode) != GNUNET_DISK_file_read (fh, nsid, sizeof (struct GNUNET_HashCode))) { GNUNET_DISK_file_close (fh); return GNUNET_SYSERR; } GNUNET_DISK_file_close (fh); return GNUNET_OK; } /** * struct used to list the pseudonym */ struct ListPseudonymClosure { /** * iterator over pseudonym */ GNUNET_PSEUDONYM_Iterator iterator; /** * Closure for iterator. */ void *closure; /** * Configuration to use. */ const struct GNUNET_CONFIGURATION_Handle *cfg; }; /** * the help function to list all available pseudonyms * @param cls point to a struct ListPseudonymClosure * @param fullname name of pseudonym */ static int list_pseudonym_helper (void *cls, const char *fullname) { struct ListPseudonymClosure *c = cls; int ret; struct GNUNET_HashCode id; int32_t rating; struct GNUNET_CONTAINER_MetaData *meta; const char *fn; char *str; char *name_unique; if (strlen (fullname) < sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded)) return GNUNET_OK; fn = &fullname[strlen (fullname) + 1 - sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded)]; if (fn[-1] != DIR_SEPARATOR) return GNUNET_OK; ret = GNUNET_OK; if (GNUNET_OK != GNUNET_CRYPTO_hash_from_string (fn, &id)) return GNUNET_OK; /* invalid name */ str = NULL; if (GNUNET_OK != GNUNET_PSEUDONYM_get_info (c->cfg, &id, &meta, &rating, &str, NULL)) { /* ignore entry. FIXME: Why? Lack of data about a pseudonym is not a reason * to ignore it... So yeah, it will have placeholders instead of name, * empty metadata container and a default rank == -1, so what? We know * its nsid - that's all we really need. Right? */ GNUNET_free (str); GNUNET_CONTAINER_meta_data_destroy (meta); return GNUNET_OK; } name_unique = GNUNET_PSEUDONYM_name_uniquify (c->cfg, &id, str, NULL); if (c->iterator != NULL) ret = c->iterator (c->closure, &id, str, name_unique, meta, rating); GNUNET_free_non_null (str); GNUNET_free_non_null (name_unique); GNUNET_CONTAINER_meta_data_destroy (meta); return ret; } /** * List all available pseudonyms. * * @param cfg overall configuration * @param iterator function to call for each pseudonym * @param closure closure for iterator * @return number of pseudonyms found */ int GNUNET_PSEUDONYM_list_all (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_PSEUDONYM_Iterator iterator, void *closure) { struct ListPseudonymClosure cls; char *fn; int ret; cls.iterator = iterator; cls.closure = closure; cls.cfg = cfg; fn = get_data_filename (cfg, PS_METADATA_DIR, NULL); GNUNET_assert (fn != NULL); GNUNET_DISK_directory_create (fn); ret = GNUNET_DISK_directory_scan (fn, &list_pseudonym_helper, &cls); GNUNET_free (fn); return ret; } /** * Change the ranking of a pseudonym. * * @param cfg overall configuration * @param nsid id of the pseudonym * @param delta by how much should the rating be * changed? * @return new rating of the pseudonym */ int GNUNET_PSEUDONYM_rank (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, int delta) { struct GNUNET_CONTAINER_MetaData *meta; int ret; int32_t ranking; char *name; name = NULL; ret = read_info (cfg, nsid, &meta, &ranking, &name); if (ret == GNUNET_SYSERR) { ranking = 0; meta = GNUNET_CONTAINER_meta_data_create (); } ranking += delta; write_pseudonym_info (cfg, nsid, meta, ranking, name); GNUNET_CONTAINER_meta_data_destroy (meta); GNUNET_free_non_null (name); return ranking; } /** * Set the pseudonym metadata, rank and name. * * @param cfg overall configuration * @param nsid id of the pseudonym * @param name name to set. Must be the non-unique version of it. * May be NULL, in which case it erases pseudonym's name! * @param md metadata to set * May be NULL, in which case it erases pseudonym's metadata! * @param rank rank to assign * @return GNUNET_OK on success, GNUNET_SYSERR on failure */ int GNUNET_PSEUDONYM_set_info (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * nsid, const char *name, const struct GNUNET_CONTAINER_MetaData *md, int rank) { GNUNET_assert (cfg != NULL); GNUNET_assert (nsid != NULL); write_pseudonym_info (cfg, nsid, md, rank, name); return GNUNET_OK; } /** * Add a pseudonym to the set of known pseudonyms. * For all pseudonym advertisements that we discover * FS should automatically call this function. * * @param cfg overall configuration * @param id the pseudonym identifier * @param meta metadata for the pseudonym */ void GNUNET_PSEUDONYM_add (const struct GNUNET_CONFIGURATION_Handle *cfg, const struct GNUNET_HashCode * id, const struct GNUNET_CONTAINER_MetaData *meta) { char *name; int32_t ranking; struct GNUNET_CONTAINER_MetaData *old; char *fn; struct stat sbuf; ranking = 0; fn = get_data_filename (cfg, PS_METADATA_DIR, id); GNUNET_assert (fn != NULL); if ((0 == STAT (fn, &sbuf)) && (GNUNET_OK == read_info (cfg, id, &old, &ranking, &name))) { GNUNET_CONTAINER_meta_data_merge (old, meta); write_pseudonym_info (cfg, id, old, ranking, name); GNUNET_CONTAINER_meta_data_destroy (old); GNUNET_free_non_null (name); } else { write_pseudonym_info (cfg, id, meta, ranking, NULL); } GNUNET_free (fn); internal_notify (id, meta, ranking); } /* end of pseudonym.c */