release/src/router/nginx/src/mail/ngx_mail_pop3_handler.c

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  * Copyright (C) Nginx, Inc.
   5  */
   6
   7
   8 #include <ngx_config.h>
   9 #include <ngx_core.h>
  10 #include <ngx_event.h>
  11 #include <ngx_mail.h>
  12 #include <ngx_mail_pop3_module.h>
  13
  14
  15 static ngx_int_t ngx_mail_pop3_user(ngx_mail_session_t *s, ngx_connection_t *c);
  16 static ngx_int_t ngx_mail_pop3_pass(ngx_mail_session_t *s, ngx_connection_t *c);
  17 static ngx_int_t ngx_mail_pop3_capa(ngx_mail_session_t *s, ngx_connection_t *c,
  18     ngx_int_t stls);
  19 static ngx_int_t ngx_mail_pop3_stls(ngx_mail_session_t *s, ngx_connection_t *c);
  20 static ngx_int_t ngx_mail_pop3_apop(ngx_mail_session_t *s, ngx_connection_t *c);
  21 static ngx_int_t ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c);
  22
  23
  24 static u_char  pop3_greeting[] = "+OK POP3 ready" CRLF;
  25 static u_char  pop3_ok[] = "+OK" CRLF;
  26 static u_char  pop3_next[] = "+ " CRLF;
  27 static u_char  pop3_username[] = "+ VXNlcm5hbWU6" CRLF;
  28 static u_char  pop3_password[] = "+ UGFzc3dvcmQ6" CRLF;
  29 static u_char  pop3_invalid_command[] = "-ERR invalid command" CRLF;
  30
  31
  32 void
  33 ngx_mail_pop3_init_session(ngx_mail_session_t *s, ngx_connection_t *c)
  34 {
  35     u_char                    *p;
  36     ngx_mail_core_srv_conf_t  *cscf;
  37     ngx_mail_pop3_srv_conf_t  *pscf;
  38
  39     pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
  40     cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module);
  41
  42     if (pscf->auth_methods
  43         & (NGX_MAIL_AUTH_APOP_ENABLED|NGX_MAIL_AUTH_CRAM_MD5_ENABLED))
  44     {
  45         if (ngx_mail_salt(s, c, cscf) != NGX_OK) {
  46             ngx_mail_session_internal_server_error(s);
  47             return;
  48         }
  49
  50         s->out.data = ngx_pnalloc(c->pool, sizeof(pop3_greeting) + s->salt.len);
  51         if (s->out.data == NULL) {
  52             ngx_mail_session_internal_server_error(s);
  53             return;
  54         }
  55
  56         p = ngx_cpymem(s->out.data, pop3_greeting, sizeof(pop3_greeting) - 3);
  57         *p++ = ' ';
  58         p = ngx_cpymem(p, s->salt.data, s->salt.len);
  59
  60         s->out.len = p - s->out.data;
  61
  62     } else {
  63         ngx_str_set(&s->out, pop3_greeting);
  64     }
  65
  66     c->read->handler = ngx_mail_pop3_init_protocol;
  67
  68     ngx_add_timer(c->read, cscf->timeout);
  69
  70     if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
  71         ngx_mail_close_connection(c);
  72     }
  73
  74     ngx_mail_send(c->write);
  75 }
  76
  77
  78 void
  79 ngx_mail_pop3_init_protocol(ngx_event_t *rev)
  80 {
  81     ngx_connection_t    *c;
  82     ngx_mail_session_t  *s;
  83
  84     c = rev->data;
  85
  86     c->log->action = "in auth state";
  87
  88     if (rev->timedout) {
  89         ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
  90         c->timedout = 1;
  91         ngx_mail_close_connection(c);
  92         return;
  93     }
  94
  95     s = c->data;
  96
  97     if (s->buffer == NULL) {
  98         if (ngx_array_init(&s->args, c->pool, 2, sizeof(ngx_str_t))
  99             == NGX_ERROR)
 100         {
 101             ngx_mail_session_internal_server_error(s);
 102             return;
 103         }
 104
 105         s->buffer = ngx_create_temp_buf(c->pool, 128);
 106         if (s->buffer == NULL) {
 107             ngx_mail_session_internal_server_error(s);
 108             return;
 109         }
 110     }
 111
 112     s->mail_state = ngx_pop3_start;
 113     c->read->handler = ngx_mail_pop3_auth_state;
 114
 115     ngx_mail_pop3_auth_state(rev);
 116 }
 117
 118
 119 void
 120 ngx_mail_pop3_auth_state(ngx_event_t *rev)
 121 {
 122     ngx_int_t            rc;
 123     ngx_connection_t    *c;
 124     ngx_mail_session_t  *s;
 125
 126     c = rev->data;
 127     s = c->data;
 128
 129     ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "pop3 auth state");
 130
 131     if (rev->timedout) {
 132         ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
 133         c->timedout = 1;
 134         ngx_mail_close_connection(c);
 135         return;
 136     }
 137
 138     if (s->out.len) {
 139         ngx_log_debug0(NGX_LOG_DEBUG_MAIL, c->log, 0, "pop3 send handler busy");
 140         s->blocked = 1;
 141         return;
 142     }
 143
 144     s->blocked = 0;
 145
 146     rc = ngx_mail_read_command(s, c);
 147
 148     if (rc == NGX_AGAIN || rc == NGX_ERROR) {
 149         return;
 150     }
 151
 152     ngx_str_set(&s->out, pop3_ok);
 153
 154     if (rc == NGX_OK) {
 155         switch (s->mail_state) {
 156
 157         case ngx_pop3_start:
 158
 159             switch (s->command) {
 160
 161             case NGX_POP3_USER:
 162                 rc = ngx_mail_pop3_user(s, c);
 163                 break;
 164
 165             case NGX_POP3_CAPA:
 166                 rc = ngx_mail_pop3_capa(s, c, 1);
 167                 break;
 168
 169             case NGX_POP3_APOP:
 170                 rc = ngx_mail_pop3_apop(s, c);
 171                 break;
 172
 173             case NGX_POP3_AUTH:
 174                 rc = ngx_mail_pop3_auth(s, c);
 175                 break;
 176
 177             case NGX_POP3_QUIT:
 178                 s->quit = 1;
 179                 break;
 180
 181             case NGX_POP3_NOOP:
 182                 break;
 183
 184             case NGX_POP3_STLS:
 185                 rc = ngx_mail_pop3_stls(s, c);
 186                 break;
 187
 188             default:
 189                 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
 190                 break;
 191             }
 192
 193             break;
 194
 195         case ngx_pop3_user:
 196
 197             switch (s->command) {
 198
 199             case NGX_POP3_PASS:
 200                 rc = ngx_mail_pop3_pass(s, c);
 201                 break;
 202
 203             case NGX_POP3_CAPA:
 204                 rc = ngx_mail_pop3_capa(s, c, 0);
 205                 break;
 206
 207             case NGX_POP3_QUIT:
 208                 s->quit = 1;
 209                 break;
 210
 211             case NGX_POP3_NOOP:
 212                 break;
 213
 214             default:
 215                 rc = NGX_MAIL_PARSE_INVALID_COMMAND;
 216                 break;
 217             }
 218
 219             break;
 220
 221         /* suppress warnings */
 222         case ngx_pop3_passwd:
 223             break;
 224
 225         case ngx_pop3_auth_login_username:
 226             rc = ngx_mail_auth_login_username(s, c, 0);
 227
 228             ngx_str_set(&s->out, pop3_password);
 229             s->mail_state = ngx_pop3_auth_login_password;
 230             break;
 231
 232         case ngx_pop3_auth_login_password:
 233             rc = ngx_mail_auth_login_password(s, c);
 234             break;
 235
 236         case ngx_pop3_auth_plain:
 237             rc = ngx_mail_auth_plain(s, c, 0);
 238             break;
 239
 240         case ngx_pop3_auth_cram_md5:
 241             rc = ngx_mail_auth_cram_md5(s, c);
 242             break;
 243         }
 244     }
 245
 246     switch (rc) {
 247
 248     case NGX_DONE:
 249         ngx_mail_auth(s, c);
 250         return;
 251
 252     case NGX_ERROR:
 253         ngx_mail_session_internal_server_error(s);
 254         return;
 255
 256     case NGX_MAIL_PARSE_INVALID_COMMAND:
 257         s->mail_state = ngx_pop3_start;
 258         s->state = 0;
 259
 260         ngx_str_set(&s->out, pop3_invalid_command);
 261
 262         /* fall through */
 263
 264     case NGX_OK:
 265
 266         s->args.nelts = 0;
 267         s->buffer->pos = s->buffer->start;
 268         s->buffer->last = s->buffer->start;
 269
 270         if (s->state) {
 271             s->arg_start = s->buffer->start;
 272         }
 273
 274         ngx_mail_send(c->write);
 275     }
 276 }
 277
 278 static ngx_int_t
 279 ngx_mail_pop3_user(ngx_mail_session_t *s, ngx_connection_t *c)
 280 {
 281     ngx_str_t  *arg;
 282
 283 #if (NGX_MAIL_SSL)
 284     if (ngx_mail_starttls_only(s, c)) {
 285         return NGX_MAIL_PARSE_INVALID_COMMAND;
 286     }
 287 #endif
 288
 289     if (s->args.nelts != 1) {
 290         return NGX_MAIL_PARSE_INVALID_COMMAND;
 291     }
 292
 293     arg = s->args.elts;
 294     s->login.len = arg[0].len;
 295     s->login.data = ngx_pnalloc(c->pool, s->login.len);
 296     if (s->login.data == NULL) {
 297         return NGX_ERROR;
 298     }
 299
 300     ngx_memcpy(s->login.data, arg[0].data, s->login.len);
 301
 302     ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
 303                    "pop3 login: \"%V\"", &s->login);
 304
 305     s->mail_state = ngx_pop3_user;
 306
 307     return NGX_OK;
 308 }
 309
 310
 311 static ngx_int_t
 312 ngx_mail_pop3_pass(ngx_mail_session_t *s, ngx_connection_t *c)
 313 {
 314     ngx_str_t  *arg;
 315
 316     if (s->args.nelts != 1) {
 317         return NGX_MAIL_PARSE_INVALID_COMMAND;
 318     }
 319
 320     arg = s->args.elts;
 321     s->passwd.len = arg[0].len;
 322     s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
 323     if (s->passwd.data == NULL) {
 324         return NGX_ERROR;
 325     }
 326
 327     ngx_memcpy(s->passwd.data, arg[0].data, s->passwd.len);
 328
 329 #if (NGX_DEBUG_MAIL_PASSWD)
 330     ngx_log_debug1(NGX_LOG_DEBUG_MAIL, c->log, 0,
 331                    "pop3 passwd: \"%V\"", &s->passwd);
 332 #endif
 333
 334     return NGX_DONE;
 335 }
 336
 337
 338 static ngx_int_t
 339 ngx_mail_pop3_capa(ngx_mail_session_t *s, ngx_connection_t *c, ngx_int_t stls)
 340 {
 341     ngx_mail_pop3_srv_conf_t  *pscf;
 342
 343     pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
 344
 345 #if (NGX_MAIL_SSL)
 346
 347     if (stls && c->ssl == NULL) {
 348         ngx_mail_ssl_conf_t  *sslcf;
 349
 350         sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
 351
 352         if (sslcf->starttls == NGX_MAIL_STARTTLS_ON) {
 353             s->out = pscf->starttls_capability;
 354             return NGX_OK;
 355         }
 356
 357         if (sslcf->starttls == NGX_MAIL_STARTTLS_ONLY) {
 358             s->out = pscf->starttls_only_capability;
 359             return NGX_OK;
 360         }
 361     }
 362
 363 #endif
 364
 365     s->out = pscf->capability;
 366     return NGX_OK;
 367 }
 368
 369
 370 static ngx_int_t
 371 ngx_mail_pop3_stls(ngx_mail_session_t *s, ngx_connection_t *c)
 372 {
 373 #if (NGX_MAIL_SSL)
 374     ngx_mail_ssl_conf_t  *sslcf;
 375
 376     if (c->ssl == NULL) {
 377         sslcf = ngx_mail_get_module_srv_conf(s, ngx_mail_ssl_module);
 378         if (sslcf->starttls) {
 379             c->read->handler = ngx_mail_starttls_handler;
 380             return NGX_OK;
 381         }
 382     }
 383
 384 #endif
 385
 386     return NGX_MAIL_PARSE_INVALID_COMMAND;
 387 }
 388
 389
 390 static ngx_int_t
 391 ngx_mail_pop3_apop(ngx_mail_session_t *s, ngx_connection_t *c)
 392 {
 393     ngx_str_t                 *arg;
 394     ngx_mail_pop3_srv_conf_t  *pscf;
 395
 396 #if (NGX_MAIL_SSL)
 397     if (ngx_mail_starttls_only(s, c)) {
 398         return NGX_MAIL_PARSE_INVALID_COMMAND;
 399     }
 400 #endif
 401
 402     if (s->args.nelts != 2) {
 403         return NGX_MAIL_PARSE_INVALID_COMMAND;
 404     }
 405
 406     pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
 407
 408     if (!(pscf->auth_methods & NGX_MAIL_AUTH_APOP_ENABLED)) {
 409         return NGX_MAIL_PARSE_INVALID_COMMAND;
 410     }
 411
 412     arg = s->args.elts;
 413
 414     s->login.len = arg[0].len;
 415     s->login.data = ngx_pnalloc(c->pool, s->login.len);
 416     if (s->login.data == NULL) {
 417         return NGX_ERROR;
 418     }
 419
 420     ngx_memcpy(s->login.data, arg[0].data, s->login.len);
 421
 422     s->passwd.len = arg[1].len;
 423     s->passwd.data = ngx_pnalloc(c->pool, s->passwd.len);
 424     if (s->passwd.data == NULL) {
 425         return NGX_ERROR;
 426     }
 427
 428     ngx_memcpy(s->passwd.data, arg[1].data, s->passwd.len);
 429
 430     ngx_log_debug2(NGX_LOG_DEBUG_MAIL, c->log, 0,
 431                    "pop3 apop: \"%V\" \"%V\"", &s->login, &s->passwd);
 432
 433     s->auth_method = NGX_MAIL_AUTH_APOP;
 434
 435     return NGX_DONE;
 436 }
 437
 438
 439 static ngx_int_t
 440 ngx_mail_pop3_auth(ngx_mail_session_t *s, ngx_connection_t *c)
 441 {
 442     ngx_int_t                  rc;
 443     ngx_mail_pop3_srv_conf_t  *pscf;
 444
 445 #if (NGX_MAIL_SSL)
 446     if (ngx_mail_starttls_only(s, c)) {
 447         return NGX_MAIL_PARSE_INVALID_COMMAND;
 448     }
 449 #endif
 450
 451     pscf = ngx_mail_get_module_srv_conf(s, ngx_mail_pop3_module);
 452
 453     if (s->args.nelts == 0) {
 454         s->out = pscf->auth_capability;
 455         s->state = 0;
 456
 457         return NGX_OK;
 458     }
 459
 460     rc = ngx_mail_auth_parse(s, c);
 461
 462     switch (rc) {
 463
 464     case NGX_MAIL_AUTH_LOGIN:
 465
 466         ngx_str_set(&s->out, pop3_username);
 467         s->mail_state = ngx_pop3_auth_login_username;
 468
 469         return NGX_OK;
 470
 471     case NGX_MAIL_AUTH_LOGIN_USERNAME:
 472
 473         ngx_str_set(&s->out, pop3_password);
 474         s->mail_state = ngx_pop3_auth_login_password;
 475
 476         return ngx_mail_auth_login_username(s, c, 1);
 477
 478     case NGX_MAIL_AUTH_PLAIN:
 479
 480         ngx_str_set(&s->out, pop3_next);
 481         s->mail_state = ngx_pop3_auth_plain;
 482
 483         return NGX_OK;
 484
 485     case NGX_MAIL_AUTH_CRAM_MD5:
 486
 487         if (!(pscf->auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED)) {
 488             return NGX_MAIL_PARSE_INVALID_COMMAND;
 489         }
 490
 491         if (ngx_mail_auth_cram_md5_salt(s, c, "+ ", 2) == NGX_OK) {
 492             s->mail_state = ngx_pop3_auth_cram_md5;
 493             return NGX_OK;
 494         }
 495
 496         return NGX_ERROR;
 497     }
 498
 499     return rc;
 500 }