src/feature/nodelist/fmt_routerstatus.c

   1 /* Copyright (c) 2001-2004, Roger Dingledine.
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file fmt_routerstatus.h
   8  * \brief Format routerstatus entries for controller, vote, or consensus.
   9  *
  10  * (Because controllers consume this format, we can't make this
  11  * code dirauth-only.)
  12  **/
  13
  14 #include "core/or/or.h"
  15 #include "feature/nodelist/fmt_routerstatus.h"
  16
  17 #include "core/or/policies.h"
  18 #include "feature/dirauth/dirvote.h"
  19 #include "feature/nodelist/routerinfo_st.h"
  20 #include "feature/nodelist/routerlist.h"
  21 #include "feature/nodelist/vote_routerstatus_st.h"
  22 #include "feature/stats/rephist.h"
  23
  24 #include "lib/crypt_ops/crypto_format.h"
  25
  26 /** Helper: write the router-status information in <b>rs</b> into a newly
  27  * allocated character buffer.  Use the same format as in network-status
  28  * documents.  If <b>version</b> is non-NULL, add a "v" line for the platform.
  29  *
  30  * Return 0 on success, -1 on failure.
  31  *
  32  * The format argument has one of the following values:
  33  *   NS_V2 - Output an entry suitable for a V2 NS opinion document
  34  *   NS_V3_CONSENSUS - Output the first portion of a V3 NS consensus entry
  35  *        for consensus_method.
  36  *   NS_V3_CONSENSUS_MICRODESC - Output the first portion of a V3 microdesc
  37  *        consensus entry for consensus_method.
  38  *   NS_V3_VOTE - Output a complete V3 NS vote. If <b>vrs</b> is present,
  39  *        it contains additional information for the vote.
  40  *   NS_CONTROL_PORT - Output a NS document for the control port.
  41  */
  42 char *
  43 routerstatus_format_entry(const routerstatus_t *rs, const char *version,
  44                           const char *protocols,
  45                           routerstatus_format_type_t format,
  46                           const vote_routerstatus_t *vrs)
  47 {
  48   char *summary;
  49   char *result = NULL;
  50
  51   char published[ISO_TIME_LEN+1];
  52   char identity64[BASE64_DIGEST_LEN+1];
  53   char digest64[BASE64_DIGEST_LEN+1];
  54   smartlist_t *chunks = smartlist_new();
  55
  56   const char *ip_str = fmt_addr(&rs->ipv4_addr);
  57   if (ip_str[0] == '\0')
  58     goto err;
  59
  60   format_iso_time(published, rs->published_on);
  61   digest_to_base64(identity64, rs->identity_digest);
  62   digest_to_base64(digest64, rs->descriptor_digest);
  63
  64   smartlist_add_asprintf(chunks,
  65                    "r %s %s %s%s%s %s %" PRIu16 " %" PRIu16 "\n",
  66                    rs->nickname,
  67                    identity64,
  68                    (format==NS_V3_CONSENSUS_MICRODESC)?"":digest64,
  69                    (format==NS_V3_CONSENSUS_MICRODESC)?"":" ",
  70                    published,
  71                    ip_str,
  72                    rs->ipv4_orport,
  73                    rs->ipv4_dirport);
  74
  75   /* TODO: Maybe we want to pass in what we need to build the rest of
  76    * this here, instead of in the caller. Then we could use the
  77    * networkstatus_type_t values, with an additional control port value
  78    * added -MP */
  79
  80   /* Possible "a" line. At most one for now. */
  81   if (!tor_addr_is_null(&rs->ipv6_addr)) {
  82     smartlist_add_asprintf(chunks, "a %s\n",
  83                            fmt_addrport(&rs->ipv6_addr, rs->ipv6_orport));
  84   }
  85
  86   if (format == NS_V3_CONSENSUS || format == NS_V3_CONSENSUS_MICRODESC)
  87     goto done;
  88
  89   smartlist_add_asprintf(chunks,
  90                    "s%s%s%s%s%s%s%s%s%s%s%s%s\n",
  91                   /* These must stay in alphabetical order. */
  92                    rs->is_authority?" Authority":"",
  93                    rs->is_bad_exit?" BadExit":"",
  94                    rs->is_exit?" Exit":"",
  95                    rs->is_fast?" Fast":"",
  96                    rs->is_possible_guard?" Guard":"",
  97                    rs->is_hs_dir?" HSDir":"",
  98                    rs->is_flagged_running?" Running":"",
  99                    rs->is_stable?" Stable":"",
 100                    rs->is_staledesc?" StaleDesc":"",
 101                    rs->is_sybil?" Sybil":"",
 102                    rs->is_v2_dir?" V2Dir":"",
 103                    rs->is_valid?" Valid":"");
 104
 105   /* length of "opt v \n" */
 106 #define V_LINE_OVERHEAD 7
 107   if (version && strlen(version) < MAX_V_LINE_LEN - V_LINE_OVERHEAD) {
 108     smartlist_add_asprintf(chunks, "v %s\n", version);
 109   }
 110   if (protocols) {
 111     smartlist_add_asprintf(chunks, "pr %s\n", protocols);
 112   }
 113
 114   if (format != NS_V2) {
 115     const routerinfo_t* desc = router_get_by_id_digest(rs->identity_digest);
 116     uint32_t bw_kb;
 117
 118     if (format != NS_CONTROL_PORT) {
 119       /* Blow up more or less nicely if we didn't get anything or not the
 120        * thing we expected.
 121        * This should be kept in sync with the function
 122        * routerstatus_has_visibly_changed and the struct routerstatus_t
 123        */
 124       if (!desc) {
 125         char id[HEX_DIGEST_LEN+1];
 126         char dd[HEX_DIGEST_LEN+1];
 127
 128         base16_encode(id, sizeof(id), rs->identity_digest, DIGEST_LEN);
 129         base16_encode(dd, sizeof(dd), rs->descriptor_digest, DIGEST_LEN);
 130         log_warn(LD_BUG, "Cannot get any descriptor for %s "
 131             "(wanted descriptor %s).",
 132             id, dd);
 133         goto err;
 134       }
 135
 136       /* This assert could fire for the control port, because
 137        * it can request NS documents before all descriptors
 138        * have been fetched. Therefore, we only do this test when
 139        * format != NS_CONTROL_PORT. */
 140       if (tor_memneq(desc->cache_info.signed_descriptor_digest,
 141             rs->descriptor_digest,
 142             DIGEST_LEN)) {
 143         char rl_d[HEX_DIGEST_LEN+1];
 144         char rs_d[HEX_DIGEST_LEN+1];
 145         char id[HEX_DIGEST_LEN+1];
 146
 147         base16_encode(rl_d, sizeof(rl_d),
 148             desc->cache_info.signed_descriptor_digest, DIGEST_LEN);
 149         base16_encode(rs_d, sizeof(rs_d), rs->descriptor_digest, DIGEST_LEN);
 150         base16_encode(id, sizeof(id), rs->identity_digest, DIGEST_LEN);
 151         log_err(LD_BUG, "descriptor digest in routerlist does not match "
 152             "the one in routerstatus: %s vs %s "
 153             "(router %s)\n",
 154             rl_d, rs_d, id);
 155
 156         tor_assert(tor_memeq(desc->cache_info.signed_descriptor_digest,
 157               rs->descriptor_digest,
 158               DIGEST_LEN));
 159       }
 160     }
 161
 162     if (format == NS_CONTROL_PORT && rs->has_bandwidth) {
 163       bw_kb = rs->bandwidth_kb;
 164     } else {
 165       tor_assert(desc);
 166       bw_kb = router_get_advertised_bandwidth_capped(desc) / 1000;
 167     }
 168     smartlist_add_asprintf(chunks,
 169                      "w Bandwidth=%d", bw_kb);
 170
 171     if (format == NS_V3_VOTE && vrs && vrs->has_measured_bw) {
 172       smartlist_add_asprintf(chunks,
 173                        " Measured=%d", vrs->measured_bw_kb);
 174     }
 175     /* Write down guardfraction information if we have it. */
 176     if (format == NS_V3_VOTE && vrs && vrs->status.has_guardfraction) {
 177       smartlist_add_asprintf(chunks,
 178                              " GuardFraction=%d",
 179                              vrs->status.guardfraction_percentage);
 180     }
 181
 182     smartlist_add_strdup(chunks, "\n");
 183
 184     if (desc) {
 185       summary = policy_summarize(desc->exit_policy, AF_INET);
 186       smartlist_add_asprintf(chunks, "p %s\n", summary);
 187       tor_free(summary);
 188     }
 189
 190     if (format == NS_V3_VOTE && vrs) {
 191       if (fast_mem_is_zero((char*)vrs->ed25519_id, ED25519_PUBKEY_LEN)) {
 192         smartlist_add_strdup(chunks, "id ed25519 none\n");
 193       } else {
 194         char ed_b64[BASE64_DIGEST256_LEN+1];
 195         digest256_to_base64(ed_b64, (const char*)vrs->ed25519_id);
 196         smartlist_add_asprintf(chunks, "id ed25519 %s\n", ed_b64);
 197       }
 198
 199       /* We'll add a series of statistics to the vote per relays so we are
 200        * able to assess what each authorities sees and help our health and
 201        * performance work. */
 202       time_t now = time(NULL);
 203       smartlist_add_asprintf(chunks, "stats wfu=%.6f tk=%lu mtbf=%.0f\n",
 204         rep_hist_get_weighted_fractional_uptime(rs->identity_digest, now),
 205         rep_hist_get_weighted_time_known(rs->identity_digest, now),
 206         rep_hist_get_stability(rs->identity_digest, now));
 207     }
 208   }
 209
 210  done:
 211   result = smartlist_join_strings(chunks, "", 0, NULL);
 212
 213  err:
 214   SMARTLIST_FOREACH(chunks, char *, cp, tor_free(cp));
 215   smartlist_free(chunks);
 216
 217   return result;
 218 }