postlicyd/main-postlicyd.c

   1 /******************************************************************************/
   2 /*          pfixtools: a collection of postfix related tools                  */
   3 /*          ~~~~~~~~~                                                         */
   4 /*  ________________________________________________________________________  */
   5 /*                                                                            */
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   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      */
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  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     */
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  22 /*  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS    */
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  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   */
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  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 bool config_refresh(void *config)
  60 {
  61     return config_reload(config);
  62 }
  63
  64 static int postfix_parsejob(query_t *query, char *p)
  65 {
  66 #define PARSE_CHECK(expr, error, ...)                                        \
  67     do {                                                                     \
  68         if (!(expr)) {                                                       \
  69             syslog(LOG_ERR, error, ##__VA_ARGS__);                           \
  70             return -1;                                                       \
  71         }                                                                    \
  72     } while (0)
  73
  74     p_clear(query, 1);
  75     query->state = SMTP_UNKNOWN;
  76     while (*p != '\n') {
  77         char *k, *v;
  78         int klen, vlen, vtk;
  79
  80         while (isblank(*p))
  81             p++;
  82         p = strchr(k = p, '=');
  83         PARSE_CHECK(p, "could not find '=' in line");
  84         for (klen = p - k; klen && isblank(k[klen]); klen--);
  85         p += 1; /* skip = */
  86
  87         while (isblank(*p))
  88             p++;
  89         p = strchr(v = p, '\n');
  90         PARSE_CHECK(p, "could not find final \\n in line");
  91         for (vlen = p - v; vlen && isblank(v[vlen]); vlen--);
  92         p += 1; /* skip \n */
  93
  94         vtk = policy_tokenize(v, vlen);
  95         switch (policy_tokenize(k, klen)) {
  96 #define CASE(up, low)  case PTK_##up: query->low = v; v[vlen] = '\0'; syslog(LOG_DEBUG, "%s = %s", ptokens[PTK_##up], query->low); break;
  97             CASE(HELO_NAME,           helo_name);
  98             CASE(QUEUE_ID,            queue_id);
  99             CASE(SENDER,              sender);
 100             CASE(RECIPIENT,           recipient);
 101             CASE(RECIPIENT_COUNT,     recipient_count);
 102             CASE(CLIENT_ADDRESS,      client_address);
 103             CASE(CLIENT_NAME,         client_name);
 104             CASE(REVERSE_CLIENT_NAME, reverse_client_name);
 105             CASE(INSTANCE,            instance);
 106             CASE(SASL_METHOD,         sasl_method);
 107             CASE(SASL_USERNAME,       sasl_username);
 108             CASE(SASL_SENDER,         sasl_sender);
 109             CASE(SIZE,                size);
 110             CASE(CCERT_SUBJECT,       ccert_subject);
 111             CASE(CCERT_ISSUER,        ccert_issuer);
 112             CASE(CCERT_FINGERPRINT,   ccert_fingerprint);
 113             CASE(ENCRYPTION_PROTOCOL, encryption_protocol);
 114             CASE(ENCRYPTION_CIPHER,   encryption_cipher);
 115             CASE(ENCRYPTION_KEYSIZE,  encryption_keysize);
 116             CASE(ETRN_DOMAIN,         etrn_domain);
 117             CASE(STRESS,              stress);
 118 #undef CASE
 119
 120           case PTK_REQUEST:
 121             PARSE_CHECK(vtk == PTK_SMTPD_ACCESS_POLICY,
 122                         "unexpected `request' value: %.*s", vlen, v);
 123             break;
 124
 125           case PTK_PROTOCOL_NAME:
 126             PARSE_CHECK(vtk == PTK_SMTP || vtk == PTK_ESMTP,
 127                         "unexpected `protocol_name' value: %.*s", vlen, v);
 128             query->esmtp = vtk == PTK_ESMTP;
 129             break;
 130
 131           case PTK_PROTOCOL_STATE:
 132             switch (vtk) {
 133 #define CASE(name)  case PTK_##name: query->state = SMTP_##name; break;
 134                 CASE(CONNECT);
 135                 CASE(EHLO);
 136                 CASE(HELO);
 137                 CASE(MAIL);
 138                 CASE(RCPT);
 139                 CASE(DATA);
 140                 CASE(END_OF_MESSAGE);
 141                 CASE(VRFY);
 142                 CASE(ETRN);
 143               default:
 144                 PARSE_CHECK(false, "unexpected `protocol_state` value: %.*s",
 145                             vlen, v);
 146 #undef CASE
 147             }
 148             break;
 149
 150           default:
 151             syslog(LOG_WARNING, "unexpected key, skipped: %.*s", klen, k);
 152             continue;
 153         }
 154     }
 155
 156     return query->state == SMTP_UNKNOWN ? -1 : 0;
 157 #undef PARSE_CHECK
 158 }
 159
 160 __attribute__((format(printf,2,0)))
 161 static void policy_answer(server_t *pcy, const char *fmt, ...)
 162 {
 163     va_list args;
 164     const query_t* query = pcy->data;
 165
 166     buffer_addstr(&pcy->obuf, "action=");
 167     va_start(args, fmt);
 168     buffer_addvf(&pcy->obuf, fmt, args);
 169     va_end(args);
 170     buffer_addstr(&pcy->obuf, "\n\n");
 171     buffer_consume(&pcy->ibuf, query->eoq - pcy->ibuf.data);
 172     epoll_modify(pcy->fd, EPOLLIN | EPOLLOUT, pcy);
 173 }
 174
 175 static bool policy_process(server_t *pcy, const config_t *config)
 176 {
 177     const query_t* query = pcy->data;
 178     const filter_t *filter;
 179     if (config->entry_points[query->state] == -1) {
 180         syslog(LOG_WARNING, "no filter defined for current protocol_state (%d)", query->state);
 181         return false;
 182     }
 183     filter = array_ptr(config->filters, config->entry_points[query->state]);
 184     while (true) {
 185         const filter_hook_t *hook = filter_run(filter, query);
 186         if (hook == NULL) {
 187             syslog(LOG_WARNING, "request aborted");
 188             return false;
 189         } else if (hook->postfix) {
 190             policy_answer(pcy, "%s", hook->value);
 191             return true;
 192         } else {
 193             filter = array_ptr(config->filters, hook->filter_id);
 194         }
 195     }
 196 }
 197
 198 static int policy_run(server_t *pcy, void* vconfig)
 199 {
 200     ssize_t search_offs = MAX(0, (ssize_t)(pcy->ibuf.len - 1));
 201     int nb = buffer_read(&pcy->ibuf, pcy->fd, -1);
 202     const char *eoq;
 203     query_t  *query  = pcy->data;
 204     const config_t *config = vconfig;
 205
 206     if (nb < 0) {
 207         if (errno == EAGAIN || errno == EINTR)
 208             return 0;
 209         UNIXERR("read");
 210         return -1;
 211     }
 212     if (nb == 0) {
 213         if (pcy->ibuf.len)
 214             syslog(LOG_ERR, "unexpected end of data");
 215         return -1;
 216     }
 217
 218     if (!(eoq = strstr(pcy->ibuf.data + search_offs, "\n\n")))
 219         return 0;
 220
 221     if (postfix_parsejob(pcy->data, pcy->ibuf.data) < 0)
 222         return -1;
 223     query->eoq = eoq + strlen("\n\n");
 224     epoll_modify(pcy->fd, 0, pcy);
 225     return policy_process(pcy, config) ? 0 : -1;
 226 }
 227
 228 int start_listener(int port)
 229 {
 230     return start_server(port, NULL, NULL);
 231 }
 232
 233 /* administrivia {{{ */
 234
 235 void usage(void)
 236 {
 237     fputs("usage: "DAEMON_NAME" [options] config\n"
 238           "\n"
 239           "Options:\n"
 240           "    -l <port>    port to listen to\n"
 241           "    -p <pidfile> file to write our pid to\n"
 242           "    -f           stay in foreground\n"
 243          , stderr);
 244 }
 245
 246 /* }}} */
 247
 248 int main(int argc, char *argv[])
 249 {
 250     bool unsafe = false;
 251     const char *pidfile = NULL;
 252     bool daemonize = true;
 253     int port = DEFAULT_PORT;
 254     bool port_from_cli = false;
 255
 256     for (int c = 0; (c = getopt(argc, argv, "hf" "l:p:")) >= 0; ) {
 257         switch (c) {
 258           case 'p':
 259             pidfile = optarg;
 260             break;
 261           case 'u':
 262             unsafe = true;
 263             break;
 264           case 'l':
 265             port = atoi(optarg);
 266             port_from_cli = true;
 267             break;
 268           case 'f':
 269             daemonize = false;
 270             break;
 271           default:
 272             usage();
 273             return EXIT_FAILURE;
 274         }
 275     }
 276
 277     if (argc - optind != 1) {
 278         usage();
 279         return EXIT_FAILURE;
 280     }
 281
 282     config_t *config = config_read(argv[optind]);
 283     if (config == NULL) {
 284         return EXIT_FAILURE;
 285     }
 286     if (port_from_cli || config->port == 0) {
 287         config->port = port;
 288     }
 289
 290     if (common_setup(pidfile, false, RUNAS_USER, RUNAS_GROUP,
 291                      daemonize) != EXIT_SUCCESS
 292         || start_listener(config->port) < 0) {
 293         config_delete(&config);
 294         return EXIT_FAILURE;
 295     }
 296     {
 297         int res = server_loop(query_starter, (delete_client_t)query_delete,
 298                               policy_run, config_refresh, config);
 299         config_delete(&config);
 300         return res;
 301     }
 302 }