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      */
  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     */
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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 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 bool policy_process(server_t *pcy, const config_t *config)
 171 {
 172     const query_t* query = pcy->data;
 173     const 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         return false;
 177     }
 178     filter = array_ptr(config->filters, config->entry_points[query->state]);
 179     while (true) {
 180         const filter_hook_t *hook = filter_run(filter, query);
 181         if (hook == NULL) {
 182             syslog(LOG_WARNING, "request aborted");
 183             return false;
 184         } else if (hook->postfix) {
 185             policy_answer(pcy, "%s", hook->value);
 186             return true;
 187         } else {
 188             filter = array_ptr(config->filters, hook->filter_id);
 189         }
 190     }
 191 }
 192
 193 static int policy_run(server_t *pcy, void* vconfig)
 194 {
 195     ssize_t search_offs = MAX(0, (ssize_t)(pcy->ibuf.len - 1));
 196     int nb = buffer_read(&pcy->ibuf, pcy->fd, -1);
 197     const char *eoq;
 198     query_t  *query  = pcy->data;
 199     const config_t *config = vconfig;
 200
 201     if (nb < 0) {
 202         if (errno == EAGAIN || errno == EINTR)
 203             return 0;
 204         UNIXERR("read");
 205         return -1;
 206     }
 207     if (nb == 0) {
 208         if (pcy->ibuf.len)
 209             syslog(LOG_ERR, "unexpected end of data");
 210         return -1;
 211     }
 212
 213     if (!(eoq = strstr(pcy->ibuf.data + search_offs, "\n\n")))
 214         return 0;
 215
 216     if (postfix_parsejob(pcy->data, pcy->ibuf.data) < 0)
 217         return -1;
 218     query->eoq = eoq + strlen("\n\n");
 219     epoll_modify(pcy->fd, 0, pcy);
 220     return policy_process(pcy, config) ? 0 : -1;
 221 }
 222
 223 int start_listener(int port)
 224 {
 225     return start_server(port, NULL, NULL);
 226 }
 227
 228 /* administrivia {{{ */
 229
 230 void usage(void)
 231 {
 232     fputs("usage: "DAEMON_NAME" [options] config\n"
 233           "\n"
 234           "Options:\n"
 235           "    -l <port>    port to listen to\n"
 236           "    -p <pidfile> file to write our pid to\n"
 237           "    -f           stay in foreground\n"
 238          , stderr);
 239 }
 240
 241 /* }}} */
 242
 243 int main(int argc, char *argv[])
 244 {
 245     bool unsafe = false;
 246     const char *pidfile = NULL;
 247     bool daemonize = true;
 248     int port = DEFAULT_PORT;
 249
 250     for (int c = 0; (c = getopt(argc, argv, "hf" "l:p:")) >= 0; ) {
 251         switch (c) {
 252           case 'p':
 253             pidfile = optarg;
 254             break;
 255           case 'u':
 256             unsafe = true;
 257             break;
 258           case 'l':
 259             port = atoi(optarg);
 260             break;
 261           case 'f':
 262             daemonize = false;
 263             break;
 264           default:
 265             usage();
 266             return EXIT_FAILURE;
 267         }
 268     }
 269
 270     if (argc - optind != 1) {
 271         usage();
 272         return EXIT_FAILURE;
 273     }
 274
 275     config_t *config = config_read(argv[optind]);
 276     if (config == NULL) {
 277         return EXIT_FAILURE;
 278     }
 279
 280     if (common_setup(pidfile, false, RUNAS_USER, RUNAS_GROUP,
 281                      daemonize) != EXIT_SUCCESS
 282         || start_listener(port) < 0) {
 283         return EXIT_FAILURE;
 284     }
 285     {
 286         int res = server_loop(query_starter, (delete_client_t)query_delete,
 287                               policy_run, config);
 288         config_delete(&config);
 289         return res;
 290     }
 291 }