diff options
Diffstat (limited to 'src/or/dirserv.c')
| -rw-r--r-- | src/or/dirserv.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/src/or/dirserv.c b/src/or/dirserv.c index 7bc91985a2..114b26163d 100644 --- a/src/or/dirserv.c +++ b/src/or/dirserv.c @@ -1915,6 +1915,13 @@ routerstatus_format_entry(const routerstatus_t *rs, const char *version, smartlist_add_asprintf(chunks, " Measured=%d", vrs->measured_bw_kb); } + /* Write down guardfraction information if we have it. */ + if (format == NS_V3_VOTE && vrs && vrs->status.has_guardfraction) { + smartlist_add_asprintf(chunks, + " GuardFraction=%d", + vrs->status.guardfraction_percentage); + } + smartlist_add(chunks, tor_strdup("\n")); if (desc) { @@ -2144,6 +2151,319 @@ clear_status_flags_on_sybil(routerstatus_t *rs) * forget to add it to this clause. */ } +/** The guardfraction of the guard with identity fingerprint <b>guard_id</b> + * is <b>guardfraction_percentage</b>. See if we have a vote routerstatus for + * this guard in <b>vote_routerstatuses</b>, and if we do, register the + * information to it. + * + * Return 1 if we applied the information and 0 if we couldn't find a + * matching guard. + * + * Requires that <b>vote_routerstatuses</b> be sorted. + */ +static int +guardfraction_line_apply(const char *guard_id, + uint32_t guardfraction_percentage, + smartlist_t *vote_routerstatuses) +{ + vote_routerstatus_t *vrs = NULL; + + tor_assert(vote_routerstatuses); + + vrs = smartlist_bsearch(vote_routerstatuses, guard_id, + compare_digest_to_vote_routerstatus_entry); + + if (!vrs) { + return 0; + } + + vrs->status.has_guardfraction = 1; + vrs->status.guardfraction_percentage = guardfraction_percentage; + + return 1; +} + +/* Given a guard line from a guardfraction file, parse it and register + * its information to <b>vote_routerstatuses</b>. + * + * Return: + * * 1 if the line was proper and its information got registered. + * * 0 if the line was proper but no currently active guard was found + * to register the guardfraction information to. + * * -1 if the line could not be parsed and set <b>err_msg</b> to a + newly allocated string containing the error message. + */ +static int +guardfraction_file_parse_guard_line(const char *guard_line, + smartlist_t *vote_routerstatuses, + char **err_msg) +{ + char guard_id[DIGEST_LEN]; + uint32_t guardfraction; + char *inputs_tmp = NULL; + int num_ok = 1; + + smartlist_t *sl = smartlist_new(); + int retval = -1; + + tor_assert(err_msg); + + /* guard_line should contain something like this: + <hex digest> <guardfraction> <appearances> */ + smartlist_split_string(sl, guard_line, " ", + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 3); + if (smartlist_len(sl) < 3) { + tor_asprintf(err_msg, "bad line '%s'", guard_line); + goto done; + } + + inputs_tmp = smartlist_get(sl, 0); + if (strlen(inputs_tmp) != HEX_DIGEST_LEN || + base16_decode(guard_id, DIGEST_LEN, inputs_tmp, HEX_DIGEST_LEN)) { + tor_asprintf(err_msg, "bad digest '%s'", inputs_tmp); + goto done; + } + + inputs_tmp = smartlist_get(sl, 1); + /* Guardfraction is an integer in [0, 100]. */ + guardfraction = + (uint32_t) tor_parse_long(inputs_tmp, 10, 0, 100, &num_ok, NULL); + if (!num_ok) { + tor_asprintf(err_msg, "wrong percentage '%s'", inputs_tmp); + goto done; + } + + /* If routerstatuses were provided, apply this info to actual routers. */ + if (vote_routerstatuses) { + retval = guardfraction_line_apply(guard_id, guardfraction, + vote_routerstatuses); + } else { + retval = 0; /* If we got this far, line was correctly formatted. */ + } + + done: + + SMARTLIST_FOREACH(sl, char *, cp, tor_free(cp)); + smartlist_free(sl); + + return retval; +} + +/** Given an inputs line from a guardfraction file, parse it and + * register its information to <b>total_consensuses</b> and + * <b>total_days</b>. + * + * Return 0 if it parsed well. Return -1 if there was an error, and + * set <b>err_msg</b> to a newly allocated string containing the + * error message. + */ +static int +guardfraction_file_parse_inputs_line(const char *inputs_line, + int *total_consensuses, + int *total_days, + char **err_msg) +{ + int retval = -1; + char *inputs_tmp = NULL; + int num_ok = 1; + smartlist_t *sl = smartlist_new(); + + tor_assert(err_msg); + + /* Second line is inputs information: + * n-inputs <total_consensuses> <total_days>. */ + smartlist_split_string(sl, inputs_line, " ", + SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 3); + if (smartlist_len(sl) < 2) { + tor_asprintf(err_msg, "incomplete line '%s'", inputs_line); + goto done; + } + + inputs_tmp = smartlist_get(sl, 0); + *total_consensuses = + (int) tor_parse_long(inputs_tmp, 10, 0, INT_MAX, &num_ok, NULL); + if (!num_ok) { + tor_asprintf(err_msg, "unparseable consensus '%s'", inputs_tmp); + goto done; + } + + inputs_tmp = smartlist_get(sl, 1); + *total_days = + (int) tor_parse_long(inputs_tmp, 10, 0, INT_MAX, &num_ok, NULL); + if (!num_ok) { + tor_asprintf(err_msg, "unparseable days '%s'", inputs_tmp); + goto done; + } + + retval = 0; + + done: + SMARTLIST_FOREACH(sl, char *, cp, tor_free(cp)); + smartlist_free(sl); + + return retval; +} + +/* Maximum age of a guardfraction file that we are willing to accept. */ +#define MAX_GUARDFRACTION_FILE_AGE (7*24*60*60) /* approx a week */ + +/** Static strings of guardfraction files. */ +#define GUARDFRACTION_DATE_STR "written-at" +#define GUARDFRACTION_INPUTS "n-inputs" +#define GUARDFRACTION_GUARD "guard-seen" +#define GUARDFRACTION_VERSION "guardfraction-file-version" + +/** Given a guardfraction file in a string, parse it and register the + * guardfraction information to the provided vote routerstatuses. + * + * This is the rough format of the guardfraction file: + * + * guardfraction-file-version 1 + * written-at <date and time> + * n-inputs <number of consesuses parsed> <number of days considered> + * + * guard-seen <fpr 1> <guardfraction percentage> <consensus appearances> + * guard-seen <fpr 2> <guardfraction percentage> <consensus appearances> + * guard-seen <fpr 3> <guardfraction percentage> <consensus appearances> + * guard-seen <fpr 4> <guardfraction percentage> <consensus appearances> + * guard-seen <fpr 5> <guardfraction percentage> <consensus appearances> + * ... + * + * Return -1 if the parsing failed and 0 if it went smoothly. Parsing + * should tolerate errors in all lines but the written-at header. + */ +STATIC int +dirserv_read_guardfraction_file_from_str(const char *guardfraction_file_str, + smartlist_t *vote_routerstatuses) +{ + config_line_t *front=NULL, *line; + int ret_tmp; + int retval = -1; + int current_line_n = 0; /* line counter for better log messages */ + + /* Guardfraction info to be parsed */ + int total_consensuses = 0; + int total_days = 0; + + /* Stats */ + int guards_read_n = 0; + int guards_applied_n = 0; + + /* Parse file and split it in lines */ + ret_tmp = config_get_lines(guardfraction_file_str, &front, 0); + if (ret_tmp < 0) { + log_warn(LD_CONFIG, "Error reading from guardfraction file"); + goto done; + } + + /* Sort routerstatuses (needed later when applying guardfraction info) */ + if (vote_routerstatuses) + smartlist_sort(vote_routerstatuses, compare_vote_routerstatus_entries); + + for (line = front; line; line=line->next) { + current_line_n++; + + if (!strcmp(line->key, GUARDFRACTION_VERSION)) { + int num_ok = 1; + unsigned int version; + + version = + (unsigned int) tor_parse_long(line->value, + 10, 0, INT_MAX, &num_ok, NULL); + + if (!num_ok || version != 1) { + log_warn(LD_GENERAL, "Got unknown guardfraction version %d.", version); + goto done; + } + } else if (!strcmp(line->key, GUARDFRACTION_DATE_STR)) { + time_t file_written_at; + time_t now = time(NULL); + + /* First line is 'written-at <date>' */ + if (parse_iso_time(line->value, &file_written_at) < 0) { + log_warn(LD_CONFIG, "Guardfraction:%d: Bad date '%s'. Ignoring", + current_line_n, line->value); + goto done; /* don't tolerate failure here. */ + } + if (file_written_at < now - MAX_GUARDFRACTION_FILE_AGE) { + log_warn(LD_CONFIG, "Guardfraction:%d: was written very long ago '%s'", + current_line_n, line->value); + goto done; /* don't tolerate failure here. */ + } + } else if (!strcmp(line->key, GUARDFRACTION_INPUTS)) { + char *err_msg = NULL; + + if (guardfraction_file_parse_inputs_line(line->value, + &total_consensuses, + &total_days, + &err_msg) < 0) { + log_warn(LD_CONFIG, "Guardfraction:%d: %s", + current_line_n, err_msg); + tor_free(err_msg); + continue; + } + + } else if (!strcmp(line->key, GUARDFRACTION_GUARD)) { + char *err_msg = NULL; + + ret_tmp = guardfraction_file_parse_guard_line(line->value, + vote_routerstatuses, + &err_msg); + if (ret_tmp < 0) { /* failed while parsing the guard line */ + log_warn(LD_CONFIG, "Guardfraction:%d: %s", + current_line_n, err_msg); + tor_free(err_msg); + continue; + } + + /* Successfully parsed guard line. Check if it was applied properly. */ + guards_read_n++; + if (ret_tmp > 0) { + guards_applied_n++; + } + } else { + log_warn(LD_CONFIG, "Unknown guardfraction line %d (%s %s)", + current_line_n, line->key, line->value); + } + } + + retval = 0; + + log_info(LD_CONFIG, + "Successfully parsed guardfraction file with %d consensuses over " + "%d days. Parsed %d nodes and applied %d of them%s.", + total_consensuses, total_days, guards_read_n, guards_applied_n, + vote_routerstatuses ? "" : " (no routerstatus provided)" ); + + done: + config_free_lines(front); + + if (retval < 0) { + return retval; + } else { + return guards_read_n; + } +} + +/** Read a guardfraction file at <b>fname</b> and load all its + * information to <b>vote_routerstatuses</b>. */ +int +dirserv_read_guardfraction_file(const char *fname, + smartlist_t *vote_routerstatuses) +{ + char *guardfraction_file_str; + + /* Read file to a string */ + guardfraction_file_str = read_file_to_str(fname, RFTS_IGNORE_MISSING, NULL); + if (!guardfraction_file_str) { + log_warn(LD_FS, "Cannot open guardfraction file '%s'. Failing.", fname); + return -1; + } + + return dirserv_read_guardfraction_file_from_str(guardfraction_file_str, + vote_routerstatuses); +} + /** * Helper function to parse out a line in the measured bandwidth file * into a measured_bw_line_t output structure. Returns -1 on failure @@ -2456,6 +2776,12 @@ dirserv_generate_networkstatus_vote_obj(crypto_pk_t *private_key, smartlist_free(routers); digestmap_free(omit_as_sybil, NULL); + /* Apply guardfraction information to routerstatuses. */ + if (options->GuardfractionFile) { + dirserv_read_guardfraction_file(options->GuardfractionFile, + routerstatuses); + } + /* This pass through applies the measured bw lines to the routerstatuses */ if (options->V3BandwidthsFile) { dirserv_read_measured_bandwidths(options->V3BandwidthsFile, |