postlicyd/main-postlicyd.c

   1 /******************************************************************************/
   2 /*          pfixtools: a collection of postfix related tools                  */
   3 /*          ~~~~~~~~~                                                         */
   4 /*  ________________________________________________________________________  */
   5 /*                                                                            */
   6 /*  Redistribution and use in source and binary forms, with or without        */
   7 /*  modification, are permitted provided that the following conditions        */
   8 /*  are met:                                                                  */
   9 /*                                                                            */
  10 /*  1. Redistributions of source code must retain the above copyright         */
  11 /*     notice, this list of conditions and the following disclaimer.          */
  12 /*  2. Redistributions in binary form must reproduce the above copyright      */
  13 /*     notice, this list of conditions and the following disclaimer in the    */
  14 /*     documentation and/or other materials provided with the distribution.   */
  15 /*  3. The names of its contributors may not be used to endorse or promote    */
  16 /*     products derived from this software without specific prior written     */
  17 /*     permission.                                                            */
  18 /*                                                                            */
  19 /*  THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND   */
  20 /*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE     */
  21 /*  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR        */
  22 /*  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS    */
  23 /*  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR    */
  24 /*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF      */
  25 /*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  */
  26 /*  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN   */
  27 /*  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)   */
  28 /*  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF    */
  29 /*  THE POSSIBILITY OF SUCH DAMAGE.                                           */
  30 /******************************************************************************/
  31
  32 /*
  33  * Copyright © 2006-2007 Pierre Habouzit
  34  * Copyright © 2008 Florent Bruneau
  35  */
  36
  37 #include <getopt.h>
  38
  39 #include "buffer.h"
  40 #include "common.h"
  41 #include "epoll.h"
  42 #include "policy_tokens.h"
  43 #include "server.h"
  44 #include "query.h"
  45 #include "config.h"
  46
  47 #define DAEMON_NAME             "postlicyd"
  48 #define DEFAULT_PORT            10000
  49 #define RUNAS_USER              "nobody"
  50 #define RUNAS_GROUP             "nogroup"
  51
  52 DECLARE_MAIN
  53
  54 static void *query_starter(server_t* server)
  55 {
  56     return query_new();
  57 }
  58
  59 static int postfix_parsejob(query_t *query, char *p)
  60 {
  61 #define PARSE_CHECK(expr, error, ...)                                        \
  62     do {                                                                     \
  63         if (!(expr)) {                                                       \
  64             syslog(LOG_ERR, error, ##__VA_ARGS__);                           \
  65             return -1;                                                       \
  66         }                                                                    \
  67     } while (0)
  68
  69     p_clear(query, 1);
  70     query->state = SMTP_UNKNOWN;
  71     while (*p != '\n') {
  72         char *k, *v;
  73         int klen, vlen, vtk;
  74
  75         while (isblank(*p))
  76             p++;
  77         p = strchr(k = p, '=');
  78         PARSE_CHECK(p, "could not find '=' in line");
  79         for (klen = p - k; klen && isblank(k[klen]); klen--);
  80         p += 1; /* skip = */
  81
  82         while (isblank(*p))
  83             p++;
  84         p = strchr(v = p, '\n');
  85         PARSE_CHECK(p, "could not find final \\n in line");
  86         for (vlen = p - v; vlen && isblank(v[vlen]); vlen--);
  87         p += 1; /* skip \n */
  88
  89         vtk = policy_tokenize(v, vlen);
  90         switch (policy_tokenize(k, klen)) {
  91 #define CASE(up, low)  case PTK_##up: query->low = v; v[vlen] = '\0'; syslog(LOG_DEBUG, "%s = %s", ptokens[PTK_##up], query->low); break;
  92             CASE(HELO_NAME,           helo_name);
  93             CASE(QUEUE_ID,            queue_id);
  94             CASE(SENDER,              sender);
  95             CASE(RECIPIENT,           recipient);
  96             CASE(RECIPIENT_COUNT,     recipient_count);
  97             CASE(CLIENT_ADDRESS,      client_address);
  98             CASE(CLIENT_NAME,         client_name);
  99             CASE(REVERSE_CLIENT_NAME, reverse_client_name);
 100             CASE(INSTANCE,            instance);
 101             CASE(SASL_METHOD,         sasl_method);
 102             CASE(SASL_USERNAME,       sasl_username);
 103             CASE(SASL_SENDER,         sasl_sender);
 104             CASE(SIZE,                size);
 105             CASE(CCERT_SUBJECT,       ccert_subject);
 106             CASE(CCERT_ISSUER,        ccert_issuer);
 107             CASE(CCERT_FINGERPRINT,   ccert_fingerprint);
 108             CASE(ENCRYPTION_PROTOCOL, encryption_protocol);
 109             CASE(ENCRYPTION_CIPHER,   encryption_cipher);
 110             CASE(ENCRYPTION_KEYSIZE,  encryption_keysize);
 111             CASE(ETRN_DOMAIN,         etrn_domain);
 112             CASE(STRESS,              stress);
 113 #undef CASE
 114
 115           case PTK_REQUEST:
 116             PARSE_CHECK(vtk == PTK_SMTPD_ACCESS_POLICY,
 117                         "unexpected `request' value: %.*s", vlen, v);
 118             break;
 119
 120           case PTK_PROTOCOL_NAME:
 121             PARSE_CHECK(vtk == PTK_SMTP || vtk == PTK_ESMTP,
 122                         "unexpected `protocol_name' value: %.*s", vlen, v);
 123             query->esmtp = vtk == PTK_ESMTP;
 124             break;
 125
 126           case PTK_PROTOCOL_STATE:
 127             switch (vtk) {
 128 #define CASE(name)  case PTK_##name: query->state = SMTP_##name; break;
 129                 CASE(CONNECT);
 130                 CASE(EHLO);
 131                 CASE(HELO);
 132                 CASE(MAIL);
 133                 CASE(RCPT);
 134                 CASE(DATA);
 135                 CASE(END_OF_MESSAGE);
 136                 CASE(VRFY);
 137                 CASE(ETRN);
 138               default:
 139                 PARSE_CHECK(false, "unexpected `protocol_state` value: %.*s",
 140                             vlen, v);
 141 #undef CASE
 142             }
 143             break;
 144
 145           default:
 146             syslog(LOG_WARNING, "unexpected key, skipped: %.*s", klen, k);
 147             continue;
 148         }
 149     }
 150
 151     return query->state == SMTP_UNKNOWN ? -1 : 0;
 152 #undef PARSE_CHECK
 153 }
 154
 155 __attribute__((format(printf,2,0)))
 156 static void policy_answer(server_t *pcy, const char *fmt, ...)
 157 {
 158     va_list args;
 159     const query_t* query = pcy->data;
 160
 161     buffer_addstr(&pcy->obuf, "action=");
 162     va_start(args, fmt);
 163     buffer_addvf(&pcy->obuf, fmt, args);
 164     va_end(args);
 165     buffer_addstr(&pcy->obuf, "\n\n");
 166     buffer_consume(&pcy->ibuf, query->eoq - pcy->ibuf.data);
 167     epoll_modify(pcy->fd, EPOLLIN | EPOLLOUT, pcy);
 168 }
 169
 170 static void policy_process(server_t *pcy, config_t *config)
 171 {
 172     const query_t* query = pcy->data;
 173     filter_t *filter;
 174     if (config->entry_points[query->state] == -1) {
 175         syslog(LOG_WARNING, "no filter defined for current protocol_state (%d)", query->state);
 176         policy_answer(pcy, "DUNNO");
 177         return;
 178     }
 179     filter = array_ptr(config->filters, config->entry_points[query->state]);
 180     while (true) {
 181         filter_hook_t *hook = filter_run(filter, query);
 182         if (hook == NULL) {
 183             policy_answer(pcy, "DUNNO");
 184             return;
 185         } else if (hook->postfix) {
 186             policy_answer(pcy, "%s", hook->value);
 187             return;
 188         } else {
 189             filter = array_ptr(config->filters, hook->filter_id);
 190         }
 191     }
 192 }
 193
 194 static int policy_run(server_t *pcy, void* vconfig)
 195 {
 196     ssize_t search_offs = MAX(0, pcy->ibuf.len - 1);
 197     int nb = buffer_read(&pcy->ibuf, pcy->fd, -1);
 198     const char *eoq;
 199     query_t  *query  = pcy->data;
 200     config_t *config = vconfig;
 201
 202     if (nb < 0) {
 203         if (errno == EAGAIN || errno == EINTR)
 204             return 0;
 205         UNIXERR("read");
 206         return -1;
 207     }
 208     if (nb == 0) {
 209         if (pcy->ibuf.len)
 210             syslog(LOG_ERR, "unexpected end of data");
 211         return -1;
 212     }
 213
 214     if (!(eoq = strstr(pcy->ibuf.data + search_offs, "\n\n")))
 215         return 0;
 216
 217     if (postfix_parsejob(pcy->data, pcy->ibuf.data) < 0)
 218         return -1;
 219     query->eoq = eoq + strlen("\n\n");
 220     epoll_modify(pcy->fd, 0, pcy);
 221     policy_process(pcy, config);
 222     return 0;
 223 }
 224
 225 int start_listener(int port)
 226 {
 227     return start_server(port, NULL, NULL);
 228 }
 229
 230 /* administrivia {{{ */
 231
 232 void usage(void)
 233 {
 234     fputs("usage: "DAEMON_NAME" [options] config\n"
 235           "\n"
 236           "Options:\n"
 237           "    -l <port>    port to listen to\n"
 238           "    -p <pidfile> file to write our pid to\n"
 239           "    -f           stay in foreground\n"
 240          , stderr);
 241 }
 242
 243 /* }}} */
 244
 245 int main(int argc, char *argv[])
 246 {
 247     bool unsafe = false;
 248     const char *pidfile = NULL;
 249     bool daemonize = true;
 250     int port = DEFAULT_PORT;
 251
 252     for (int c = 0; (c = getopt(argc, argv, "hf" "l:p:")) >= 0; ) {
 253         switch (c) {
 254           case 'p':
 255             pidfile = optarg;
 256             break;
 257           case 'u':
 258             unsafe = true;
 259             break;
 260           case 'l':
 261             port = atoi(optarg);
 262             break;
 263           case 'f':
 264             daemonize = false;
 265             break;
 266           default:
 267             usage();
 268             return EXIT_FAILURE;
 269         }
 270     }
 271
 272     if (argc - optind != 1) {
 273         usage();
 274         return EXIT_FAILURE;
 275     }
 276
 277     config_t *config = config_read(argv[optind]);
 278     if (config == NULL) {
 279         return EXIT_FAILURE;
 280     }
 281
 282     if (common_setup(pidfile, false, RUNAS_USER, RUNAS_GROUP,
 283                      daemonize) != EXIT_SUCCESS
 284         || start_listener(port) < 0) {
 285         return EXIT_FAILURE;
 286     }
 287     {
 288         int res = server_loop(query_starter, (delete_client_t)query_delete,
 289                               policy_run, config);
 290         config_delete(&config);
 291         return res;
 292     }
 293 }