postlicyd/config.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 © 2008 Florent Bruneau
  34  */
  35
  36 #include "file.h"
  37 #include "config.h"
  38 #include "str.h"
  39 #include "resources.h"
  40
  41 #define config_param_register(Param)
  42
  43 /* Filter to execute on "CONNECT"
  44  */
  45 config_param_register("client_filter");
  46
  47 /* Filter to execute on "MAIL FROM"
  48  */
  49 config_param_register("sender_filter");
  50
  51 /* Filter to execute on "RCPT TO"
  52  */
  53 config_param_register("recipient_filter");
  54
  55 /* Filter to execute on "DATA"
  56  */
  57 config_param_register("data_filter");
  58
  59 /* Filter to execute on "END-OF-DATA"
  60  */
  61 config_param_register("end_of_data_filter");
  62
  63 /* Filter to execute on "ETRN"
  64  */
  65 config_param_register("etrn_filter");
  66
  67 /* Filter to execute on "HELO"
  68  */
  69 config_param_register("helo_filter");
  70 config_param_register("ehlo_filter");
  71
  72 /* Filter to execute on "VRFY"
  73  */
  74 config_param_register("verify_filter");
  75
  76
  77 /* Where to bind the server.
  78  */
  79 config_param_register("port");
  80
  81
  82 static config_t *global_config = NULL;
  83
  84 static inline config_t *config_new(void)
  85 {
  86     config_t *config = p_new(config_t, 1);
  87     global_config = config;
  88     return config;
  89 }
  90
  91 static void config_close(config_t *config)
  92 {
  93     for (int i = 0 ; i < SMTP_count ; ++i) {
  94         config->entry_points[i] = -1;
  95     }
  96     array_deep_wipe(config->filters, filter_wipe);
  97     array_deep_wipe(config->params, filter_params_wipe);
  98 }
  99
 100 void config_delete(config_t **config)
 101 {
 102     if (*config) {
 103         config_close(*config);
 104         p_delete(config);
 105         global_config = NULL;
 106     }
 107 }
 108
 109 static void config_exit()
 110 {
 111     if (global_config) {
 112         config_delete(&global_config);
 113     }
 114 }
 115 module_exit(config_exit);
 116
 117
 118 static bool config_parse(config_t *config)
 119 {
 120     filter_t filter;
 121     file_map_t map;
 122     const char *p;
 123     int line = 0;
 124     const char *linep;
 125     bool in_section = false;
 126     bool end_of_section = false;
 127
 128     char key[BUFSIZ];
 129     char value[BUFSIZ];
 130     int key_len, value_len;
 131
 132     if (!file_map_open(&map, config->filename, false)) {
 133         return false;
 134     }
 135
 136     filter_init(&filter);
 137     linep = p = map.map;
 138
 139 #define READ_LOG(Lev, Fmt, ...)                                                \
 140     __log(LOG_ ## Lev, "config file %s:%d:%d: " Fmt, config->filename,         \
 141            line + 1, (int)(p - linep + 1), ##__VA_ARGS__)
 142 #define READ_ERROR(Fmt, ...)                                                   \
 143     do {                                                                       \
 144         READ_LOG(ERR, Fmt, ##__VA_ARGS__);                                     \
 145         goto error;                                                            \
 146     } while (0)
 147 #define ADD_IN_BUFFER(Buffer, Len, Char)                                       \
 148     do {                                                                       \
 149         if ((Len) >= BUFSIZ - 1) {                                             \
 150             READ_ERROR("unreasonnable long line");                             \
 151         }                                                                      \
 152         (Buffer)[(Len)++] = (Char);                                            \
 153         (Buffer)[(Len)]   = '\0';                                              \
 154     } while (0)
 155 #define READ_NEXT                                                              \
 156     do {                                                                       \
 157         if (*p == '\n') {                                                      \
 158             ++line;                                                            \
 159             linep = p + 1;                                                     \
 160         }                                                                      \
 161         if (++p >= map.end) {                                                  \
 162             if (!end_of_section) {                                             \
 163                 if (in_section) {                                              \
 164                     goto badeof;                                               \
 165                 } else {                                                       \
 166                     goto ok;                                                   \
 167                 }                                                              \
 168             }                                                                  \
 169         }                                                                      \
 170     } while (0)
 171 #define READ_BLANK                                                             \
 172     do {                                                                       \
 173         bool in_comment = false;                                               \
 174         while (in_comment || isspace(*p) || *p == '#') {                       \
 175             if (*p == '\n') {                                                  \
 176                 in_comment = false;                                            \
 177             } else if (*p == '#') {                                            \
 178                 in_comment = true;                                             \
 179             }                                                                  \
 180             READ_NEXT;                                                         \
 181         }                                                                      \
 182     } while (0)
 183 #define READ_TOKEN(Name, Buffer, Len)                                          \
 184     do {                                                                       \
 185         (Len) = 0;                                                             \
 186         (Buffer)[0] = '\0';                                                    \
 187         if (!isalpha(*p)) {                                                    \
 188             READ_ERROR("invalid %s, unexpected character '%c'", Name, *p);     \
 189         }                                                                      \
 190         do {                                                                   \
 191             ADD_IN_BUFFER(Buffer, Len, *p);                                    \
 192             READ_NEXT;                                                         \
 193         } while (isalnum(*p) || *p == '_');                                    \
 194     } while (0)
 195 #define READ_STRING(Name, Buffer, Len, Ignore)                                 \
 196     do {                                                                       \
 197         (Len) = 0;                                                             \
 198         (Buffer)[0] = '\0';                                                    \
 199         if (*p == '"') {                                                       \
 200             bool escaped = false;                                              \
 201             while (*p == '"') {                                                \
 202                 READ_NEXT;                                                     \
 203                 while (true) {                                                 \
 204                     if (*p == '\n') {                                          \
 205                         READ_ERROR("string must not contain EOL");             \
 206                     } else if (escaped) {                                      \
 207                         ADD_IN_BUFFER(Buffer, Len, *p);                        \
 208                         escaped = false;                                       \
 209                     } else if (*p == '\\') {                                   \
 210                         escaped = true;                                        \
 211                     } else if (*p == '"') {                                    \
 212                         READ_NEXT;                                \
 213                         break;                                                 \
 214                     } else {                                                   \
 215                         ADD_IN_BUFFER(Buffer, Len, *p);                        \
 216                     }                                                          \
 217                     READ_NEXT;                                                 \
 218                 }                                                              \
 219                 READ_BLANK;                                                    \
 220             }                                                                  \
 221             if (*p != ';') {                                                   \
 222                 READ_ERROR("%s must end with a ';'", Name);                    \
 223             }                                                                  \
 224         } else {                                                               \
 225             bool escaped = false;                                              \
 226             while (*p != ';' && isascii(*p) && (isprint(*p) || isspace(*p))) { \
 227                 if (escaped) {                                                 \
 228                     if (*p == '\r' || *p == '\n') {                            \
 229                         READ_BLANK;                                            \
 230                     } else {                                                   \
 231                         ADD_IN_BUFFER(Buffer, Len, '\\');                      \
 232                     }                                                          \
 233                     escaped = false;                                           \
 234                 }                                                              \
 235                 if (*p == '\\') {                                              \
 236                     escaped = true;                                            \
 237                 } else if (*p == '\r' || *p == '\n') {                         \
 238                     READ_ERROR("%s must not contain EOL", Name);               \
 239                 } else {                                                       \
 240                     ADD_IN_BUFFER(Buffer, Len, *p);                            \
 241                 }                                                              \
 242                 READ_NEXT;                                                     \
 243             }                                                                  \
 244             if (escaped) {                                                     \
 245                 ADD_IN_BUFFER(Buffer, Len, '\\');                              \
 246             }                                                                  \
 247             while ((Len) > 0 && isspace((Buffer)[(Len) - 1])) {                \
 248                 (Buffer)[--(Len)] = '\0';                                      \
 249             }                                                                  \
 250         }                                                                      \
 251         end_of_section = Ignore;                                               \
 252         READ_NEXT;                                                             \
 253     } while(0)
 254
 255
 256 read_section:
 257     if (p >= map.end) {
 258         goto ok;
 259     }
 260
 261     value[0] = key[0] = '\0';
 262     value_len = key_len = 0;
 263
 264     in_section = end_of_section = false;
 265     READ_BLANK;
 266     in_section = true;
 267     READ_TOKEN("section name", key, key_len);
 268     READ_BLANK;
 269     switch (*p) {
 270       case '=':
 271         READ_NEXT;
 272         goto read_param_value;
 273       case '{':
 274         READ_NEXT;
 275         goto read_filter;
 276       default:
 277         READ_ERROR("invalid character '%c', expected '=' or '{'", *p);
 278     }
 279
 280 read_param_value:
 281     READ_BLANK;
 282     READ_STRING("parameter value", value, value_len, true);
 283     {
 284         filter_param_t param;
 285         param.type  = param_tokenize(key, key_len);
 286         if (param.type != ATK_UNKNOWN) {
 287             param.value     = p_dupstr(value, value_len);
 288             param.value_len = value_len;
 289             array_add(config->params, param);
 290         } else {
 291             READ_LOG(INFO, "unknown parameter %.*s", key_len, key);
 292         }
 293     }
 294     goto read_section;
 295
 296 read_filter:
 297     filter_set_name(&filter, key, key_len);
 298     READ_BLANK;
 299     while (*p != '}') {
 300         READ_TOKEN("filter parameter name", key, key_len);
 301         READ_BLANK;
 302         if (*p != '=') {
 303             READ_ERROR("invalid character '%c', expected '='", *p);
 304         }
 305         READ_NEXT;
 306         READ_BLANK;
 307         READ_STRING("filter parameter value", value, value_len, false);
 308         READ_BLANK;
 309         if (strcmp(key, "type") == 0) {
 310             if (!filter_set_type(&filter, value, value_len)) {
 311                 READ_ERROR("unknow filter type (%s) for filter %s",
 312                            value, filter.name);
 313             }
 314         } else if (key_len > 3 && strncmp(key, "on_", 3) == 0) {
 315             if (!filter_add_hook(&filter, key + 3, key_len - 3,
 316                                  value, value_len)) {
 317                 READ_ERROR("hook %s not supported by filter %s",
 318                            key + 3, filter.name);
 319             }
 320         } else {
 321             /* filter_add_param failure mean unknown type or unsupported type.
 322              * this are non-fatal errors.
 323              */
 324             (void)filter_add_param(&filter, key, key_len, value, value_len);
 325         }
 326     }
 327     end_of_section = true;
 328     READ_NEXT;
 329     array_add(config->filters, filter);
 330     filter_init(&filter);
 331     goto read_section;
 332
 333 ok:
 334     file_map_close(&map);
 335     return true;
 336
 337 badeof:
 338     err("Unexpected end of file");
 339
 340 error:
 341     if (filter.name) {
 342         filter_wipe(&filter);
 343     }
 344     file_map_close(&map);
 345     return false;
 346 }
 347
 348 static bool config_build_structure(config_t *config)
 349 {
 350     bool ok = true;
 351     if (config->filters.len > 0) {
 352 #       define QSORT_TYPE filter_t
 353 #       define QSORT_BASE config->filters.data
 354 #       define QSORT_NELT config->filters.len
 355 #       define QSORT_LT(a,b) strcmp(a->name, b->name) < 0
 356 #       include "qsort.c"
 357     }
 358
 359     foreach (filter_t *filter, config->filters) {
 360         if (!filter_update_references(filter, &config->filters)) {
 361             ok = false;
 362             break;
 363         }
 364     }}
 365     if (!ok) {
 366         return false;
 367     }
 368     if (!filter_check_safety(&config->filters)) {
 369         return false;
 370     }
 371
 372     ok = false;
 373 #define PARSE_CHECK(Expr, Fmt, ...)                                            \
 374     if (!(Expr)) {                                                             \
 375         err(Fmt, ##__VA_ARGS__);                                               \
 376         return false;                                                          \
 377     }
 378     foreach (filter_param_t *param, config->params) {
 379         switch (param->type) {
 380 #define   CASE(Param, State)                                                   \
 381             case ATK_ ## Param ## _FILTER:                                     \
 382               ok = true;                                                       \
 383               config->entry_points[SMTP_ ## State]                             \
 384                   = filter_find_with_name(&config->filters, param->value);     \
 385               PARSE_CHECK(config->entry_points[SMTP_ ## State] >= 0,           \
 386                           "invalid filter name %s", param->value);             \
 387               break;
 388           CASE(CLIENT,      CONNECT)
 389           CASE(EHLO,        EHLO)
 390           CASE(HELO,        HELO)
 391           CASE(SENDER,      MAIL)
 392           CASE(RECIPIENT,   RCPT)
 393           CASE(DATA,        DATA)
 394           CASE(END_OF_DATA, END_OF_MESSAGE)
 395           CASE(VERIFY,      VRFY)
 396           CASE(ETRN,        ETRN)
 397 #undef    CASE
 398           FILTER_PARAM_PARSE_INT(PORT, config->port);
 399           default: break;
 400         }
 401     }}
 402     array_deep_wipe(config->params, filter_params_wipe);
 403
 404     if (!ok) {
 405         err("no entry point defined");
 406     }
 407     return ok;
 408 }
 409
 410 static bool config_build_filters(config_t *config)
 411 {
 412     foreach (filter_t *filter, config->filters) {
 413         if (!filter_build(filter)) {
 414             return false;
 415         }
 416     }}
 417
 418     return true;
 419 }
 420
 421 static bool config_load(config_t *config) {
 422     config_close(config);
 423
 424     if (!config_parse(config)) {
 425         err("Invalid configuration: cannot parse configuration file \"%s\"", config->filename);
 426         return false;
 427     }
 428     if (!config_build_structure(config)) {
 429         err("Invalid configuration: inconsistent filter structure");
 430         return false;
 431     }
 432     if (!config_build_filters(config)) {
 433         err("Invalid configuration: invalid filter");
 434         return false;
 435     }
 436
 437     resource_garbage_collect();
 438     return true;
 439 }
 440
 441 bool config_reload(config_t *config)
 442 {
 443     return config_load(config);
 444 }
 445
 446 config_t *config_read(const char *file)
 447 {
 448     config_t *config = config_new();
 449     config->filename = file;
 450     if (!config_reload(config)) {
 451         config_delete(&config);
 452         return NULL;
 453     }
 454     return config;
 455 }
 456
 457 bool config_check(const char *file)
 458 {
 459     config_t *config = config_new();
 460     config->filename = file;
 461
 462     bool ret = config_parse(config) && config_build_structure(config);
 463
 464     config_delete(&config);
 465     return ret;
 466 }