nginx/src/mail/ngx_mail_parse.c

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  */
   5
   6
   7 #include <ngx_config.h>
   8 #include <ngx_core.h>
   9 #include <ngx_event.h>
  10 #include <ngx_mail.h>
  11
  12
  13 ngx_int_t
  14 ngx_mail_pop3_parse_command(ngx_mail_session_t *s)
  15 {
  16     u_char      ch, *p, *c, c0, c1, c2, c3;
  17     ngx_str_t  *arg;
  18     enum {
  19         sw_start = 0,
  20         sw_spaces_before_argument,
  21         sw_argument,
  22         sw_almost_done
  23     } state;
  24
  25     state = s->state;
  26
  27     for (p = s->buffer->pos; p < s->buffer->last; p++) {
  28         ch = *p;
  29
  30         switch (state) {
  31
  32         /* POP3 command */
  33         case sw_start:
  34             if (ch == ' ' || ch == CR || ch == LF) {
  35                 c = s->buffer->start;
  36
  37                 if (p - c == 4) {
  38
  39                     c0 = ngx_toupper(c[0]);
  40                     c1 = ngx_toupper(c[1]);
  41                     c2 = ngx_toupper(c[2]);
  42                     c3 = ngx_toupper(c[3]);
  43
  44                     if (c0 == 'U' && c1 == 'S' && c2 == 'E' && c3 == 'R')
  45                     {
  46                         s->command = NGX_POP3_USER;
  47
  48                     } else if (c0 == 'P' && c1 == 'A' && c2 == 'S' && c3 == 'S')
  49                     {
  50                         s->command = NGX_POP3_PASS;
  51
  52                     } else if (c0 == 'A' && c1 == 'P' && c2 == 'O' && c3 == 'P')
  53                     {
  54                         s->command = NGX_POP3_APOP;
  55
  56                     } else if (c0 == 'Q' && c1 == 'U' && c2 == 'I' && c3 == 'T')
  57                     {
  58                         s->command = NGX_POP3_QUIT;
  59
  60                     } else if (c0 == 'C' && c1 == 'A' && c2 == 'P' && c3 == 'A')
  61                     {
  62                         s->command = NGX_POP3_CAPA;
  63
  64                     } else if (c0 == 'A' && c1 == 'U' && c2 == 'T' && c3 == 'H')
  65                     {
  66                         s->command = NGX_POP3_AUTH;
  67
  68                     } else if (c0 == 'N' && c1 == 'O' && c2 == 'O' && c3 == 'P')
  69                     {
  70                         s->command = NGX_POP3_NOOP;
  71 #if (NGX_MAIL_SSL)
  72                     } else if (c0 == 'S' && c1 == 'T' && c2 == 'L' && c3 == 'S')
  73                     {
  74                         s->command = NGX_POP3_STLS;
  75 #endif
  76                     } else {
  77                         goto invalid;
  78                     }
  79
  80                 } else {
  81                     goto invalid;
  82                 }
  83
  84                 switch (ch) {
  85                 case ' ':
  86                     state = sw_spaces_before_argument;
  87                     break;
  88                 case CR:
  89                     state = sw_almost_done;
  90                     break;
  91                 case LF:
  92                     goto done;
  93                 }
  94                 break;
  95             }
  96
  97             if ((ch < 'A' || ch > 'Z') && (ch < 'a' || ch > 'z')) {
  98                 goto invalid;
  99             }
 100
 101             break;
 102
 103         case sw_spaces_before_argument:
 104             switch (ch) {
 105             case ' ':
 106                 break;
 107             case CR:
 108                 state = sw_almost_done;
 109                 s->arg_end = p;
 110                 break;
 111             case LF:
 112                 s->arg_end = p;
 113                 goto done;
 114             default:
 115                 if (s->args.nelts <= 2) {
 116                     state = sw_argument;
 117                     s->arg_start = p;
 118                     break;
 119                 }
 120                 goto invalid;
 121             }
 122             break;
 123
 124         case sw_argument:
 125             switch (ch) {
 126
 127             case ' ':
 128
 129                 /*
 130                  * the space should be considered as part of the at username
 131                  * or password, but not of argument in other commands
 132                  */
 133
 134                 if (s->command == NGX_POP3_USER
 135                     || s->command == NGX_POP3_PASS)
 136                 {
 137                     break;
 138                 }
 139
 140                 /* fall through */
 141
 142             case CR:
 143             case LF:
 144                 arg = ngx_array_push(&s->args);
 145                 if (arg == NULL) {
 146                     return NGX_ERROR;
 147                 }
 148                 arg->len = p - s->arg_start;
 149                 arg->data = s->arg_start;
 150                 s->arg_start = NULL;
 151
 152                 switch (ch) {
 153                 case ' ':
 154                     state = sw_spaces_before_argument;
 155                     break;
 156                 case CR:
 157                     state = sw_almost_done;
 158                     break;
 159                 case LF:
 160                     goto done;
 161                 }
 162                 break;
 163
 164             default:
 165                 break;
 166             }
 167             break;
 168
 169         case sw_almost_done:
 170             switch (ch) {
 171             case LF:
 172                 goto done;
 173             default:
 174                 goto invalid;
 175             }
 176         }
 177     }
 178
 179     s->buffer->pos = p;
 180     s->state = state;
 181
 182     return NGX_AGAIN;
 183
 184 done:
 185
 186     s->buffer->pos = p + 1;
 187
 188     if (s->arg_start) {
 189         arg = ngx_array_push(&s->args);
 190         if (arg == NULL) {
 191             return NGX_ERROR;
 192         }
 193         arg->len = s->arg_end - s->arg_start;
 194         arg->data = s->arg_start;
 195         s->arg_start = NULL;
 196     }
 197
 198     s->state = (s->command != NGX_POP3_AUTH) ? sw_start : sw_argument;
 199
 200     return NGX_OK;
 201
 202 invalid:
 203
 204     s->state = sw_start;
 205     s->arg_start = NULL;
 206
 207     return NGX_MAIL_PARSE_INVALID_COMMAND;
 208 }
 209
 210
 211 ngx_int_t
 212 ngx_mail_imap_parse_command(ngx_mail_session_t *s)
 213 {
 214     u_char      ch, *p, *c;
 215     ngx_str_t  *arg;
 216     enum {
 217         sw_start = 0,
 218         sw_spaces_before_command,
 219         sw_command,
 220         sw_spaces_before_argument,
 221         sw_argument,
 222         sw_backslash,
 223         sw_literal,
 224         sw_no_sync_literal_argument,
 225         sw_start_literal_argument,
 226         sw_literal_argument,
 227         sw_end_literal_argument,
 228         sw_almost_done
 229     } state;
 230
 231     state = s->state;
 232
 233     for (p = s->buffer->pos; p < s->buffer->last; p++) {
 234         ch = *p;
 235
 236         switch (state) {
 237
 238         /* IMAP tag */
 239         case sw_start:
 240             switch (ch) {
 241             case ' ':
 242                 s->tag.len = p - s->buffer->start + 1;
 243                 s->tag.data = s->buffer->start;
 244                 state = sw_spaces_before_command;
 245                 break;
 246             case CR:
 247                 s->state = sw_start;
 248                 return NGX_MAIL_PARSE_INVALID_COMMAND;
 249             case LF:
 250                 s->state = sw_start;
 251                 return NGX_MAIL_PARSE_INVALID_COMMAND;
 252             }
 253             break;
 254
 255         case sw_spaces_before_command:
 256             switch (ch) {
 257             case ' ':
 258                 break;
 259             case CR:
 260                 s->state = sw_start;
 261                 return NGX_MAIL_PARSE_INVALID_COMMAND;
 262             case LF:
 263                 s->state = sw_start;
 264                 return NGX_MAIL_PARSE_INVALID_COMMAND;
 265             default:
 266                 s->cmd_start = p;
 267                 state = sw_command;
 268                 break;
 269             }
 270             break;
 271
 272         case sw_command:
 273             if (ch == ' ' || ch == CR || ch == LF) {
 274
 275                 c = s->cmd_start;
 276
 277                 switch (p - c) {
 278
 279                 case 4:
 280                     if ((c[0] == 'N' || c[0] == 'n')
 281                         && (c[1] == 'O'|| c[1] == 'o')
 282                         && (c[2] == 'O'|| c[2] == 'o')
 283                         && (c[3] == 'P'|| c[3] == 'p'))
 284                     {
 285                         s->command = NGX_IMAP_NOOP;
 286
 287                     } else {
 288                         goto invalid;
 289                     }
 290                     break;
 291
 292                 case 5:
 293                     if ((c[0] == 'L'|| c[0] == 'l')
 294                         && (c[1] == 'O'|| c[1] == 'o')
 295                         && (c[2] == 'G'|| c[2] == 'g')
 296                         && (c[3] == 'I'|| c[3] == 'i')
 297                         && (c[4] == 'N'|| c[4] == 'n'))
 298                     {
 299                         s->command = NGX_IMAP_LOGIN;
 300
 301                     } else {
 302                         goto invalid;
 303                     }
 304                     break;
 305
 306                 case 6:
 307                     if ((c[0] == 'L'|| c[0] == 'l')
 308                         && (c[1] == 'O'|| c[1] == 'o')
 309                         && (c[2] == 'G'|| c[2] == 'g')
 310                         && (c[3] == 'O'|| c[3] == 'o')
 311                         && (c[4] == 'U'|| c[4] == 'u')
 312                         && (c[5] == 'T'|| c[5] == 't'))
 313                     {
 314                         s->command = NGX_IMAP_LOGOUT;
 315
 316                     } else {
 317                         goto invalid;
 318                     }
 319                     break;
 320
 321 #if (NGX_MAIL_SSL)
 322                 case 8:
 323                     if ((c[0] == 'S'|| c[0] == 's')
 324                         && (c[1] == 'T'|| c[1] == 't')
 325                         && (c[2] == 'A'|| c[2] == 'a')
 326                         && (c[3] == 'R'|| c[3] == 'r')
 327                         && (c[4] == 'T'|| c[4] == 't')
 328                         && (c[5] == 'T'|| c[5] == 't')
 329                         && (c[6] == 'L'|| c[6] == 'l')
 330                         && (c[7] == 'S'|| c[7] == 's'))
 331                     {
 332                         s->command = NGX_IMAP_STARTTLS;
 333
 334                     } else {
 335                         goto invalid;
 336                     }
 337                     break;
 338 #endif
 339
 340                 case 10:
 341                     if ((c[0] == 'C'|| c[0] == 'c')
 342                         && (c[1] == 'A'|| c[1] == 'a')
 343                         && (c[2] == 'P'|| c[2] == 'p')
 344                         && (c[3] == 'A'|| c[3] == 'a')
 345                         && (c[4] == 'B'|| c[4] == 'b')
 346                         && (c[5] == 'I'|| c[5] == 'i')
 347                         && (c[6] == 'L'|| c[6] == 'l')
 348                         && (c[7] == 'I'|| c[7] == 'i')
 349                         && (c[8] == 'T'|| c[8] == 't')
 350                         && (c[9] == 'Y'|| c[9] == 'y'))
 351                     {
 352                         s->command = NGX_IMAP_CAPABILITY;
 353
 354                     } else {
 355                         goto invalid;
 356                     }
 357                     break;
 358
 359                 case 12:
 360                     if ((c[0] == 'A'|| c[0] == 'a')
 361                         && (c[1] == 'U'|| c[1] == 'u')
 362                         && (c[2] == 'T'|| c[2] == 't')
 363                         && (c[3] == 'H'|| c[3] == 'h')
 364                         && (c[4] == 'E'|| c[4] == 'e')
 365                         && (c[5] == 'N'|| c[5] == 'n')
 366                         && (c[6] == 'T'|| c[6] == 't')
 367                         && (c[7] == 'I'|| c[7] == 'i')
 368                         && (c[8] == 'C'|| c[8] == 'c')
 369                         && (c[9] == 'A'|| c[9] == 'a')
 370                         && (c[10] == 'T'|| c[10] == 't')
 371                         && (c[11] == 'E'|| c[11] == 'e'))
 372                     {
 373                         s->command = NGX_IMAP_AUTHENTICATE;
 374
 375                     } else {
 376                         goto invalid;
 377                     }
 378                     break;
 379
 380                 default:
 381                     goto invalid;
 382                 }
 383
 384                 switch (ch) {
 385                 case ' ':
 386                     state = sw_spaces_before_argument;
 387                     break;
 388                 case CR:
 389                     state = sw_almost_done;
 390                     break;
 391                 case LF:
 392                     goto done;
 393                 }
 394                 break;
 395             }
 396
 397             if ((ch < 'A' || ch > 'Z') && (ch < 'a' || ch > 'z')) {
 398                 goto invalid;
 399             }
 400
 401             break;
 402
 403         case sw_spaces_before_argument:
 404             switch (ch) {
 405             case ' ':
 406                 break;
 407             case CR:
 408                 state = sw_almost_done;
 409                 s->arg_end = p;
 410                 break;
 411             case LF:
 412                 s->arg_end = p;
 413                 goto done;
 414             case '"':
 415                 if (s->args.nelts <= 2) {
 416                     s->quoted = 1;
 417                     s->arg_start = p + 1;
 418                     state = sw_argument;
 419                     break;
 420                 }
 421                 goto invalid;
 422             case '{':
 423                 if (s->args.nelts <= 2) {
 424                     state = sw_literal;
 425                     break;
 426                 }
 427                 goto invalid;
 428             default:
 429                 if (s->args.nelts <= 2) {
 430                     s->arg_start = p;
 431                     state = sw_argument;
 432                     break;
 433                 }
 434                 goto invalid;
 435             }
 436             break;
 437
 438         case sw_argument:
 439             if (ch == ' ' && s->quoted) {
 440                 break;
 441             }
 442
 443             switch (ch) {
 444             case '"':
 445                 if (!s->quoted) {
 446                     break;
 447                 }
 448                 s->quoted = 0;
 449                 /* fall through */
 450             case ' ':
 451             case CR:
 452             case LF:
 453                 arg = ngx_array_push(&s->args);
 454                 if (arg == NULL) {
 455                     return NGX_ERROR;
 456                 }
 457                 arg->len = p - s->arg_start;
 458                 arg->data = s->arg_start;
 459                 s->arg_start = NULL;
 460
 461                 switch (ch) {
 462                 case '"':
 463                 case ' ':
 464                     state = sw_spaces_before_argument;
 465                     break;
 466                 case CR:
 467                     state = sw_almost_done;
 468                     break;
 469                 case LF:
 470                     goto done;
 471                 }
 472                 break;
 473             case '\\':
 474                 if (s->quoted) {
 475                     s->backslash = 1;
 476                     state = sw_backslash;
 477                 }
 478                 break;
 479             }
 480             break;
 481
 482         case sw_backslash:
 483             switch (ch) {
 484             case CR:
 485             case LF:
 486                 goto invalid;
 487             default:
 488                 state = sw_argument;
 489             }
 490             break;
 491
 492         case sw_literal:
 493             if (ch >= '0' && ch <= '9') {
 494                 s->literal_len = s->literal_len * 10 + (ch - '0');
 495                 break;
 496             }
 497             if (ch == '}') {
 498                 state = sw_start_literal_argument;
 499                 break;
 500             }
 501             if (ch == '+') {
 502                 state = sw_no_sync_literal_argument;
 503                 break;
 504             }
 505             goto invalid;
 506
 507         case sw_no_sync_literal_argument:
 508             if (ch == '}') {
 509                 s->no_sync_literal = 1;
 510                 state = sw_start_literal_argument;
 511                 break;
 512             }
 513             goto invalid;
 514
 515         case sw_start_literal_argument:
 516             switch (ch) {
 517             case CR:
 518                 break;
 519             case LF:
 520                 s->buffer->pos = p + 1;
 521                 s->arg_start = p + 1;
 522                 if (s->no_sync_literal == 0) {
 523                     s->state = sw_literal_argument;
 524                     return NGX_IMAP_NEXT;
 525                 }
 526                 state = sw_literal_argument;
 527                 s->no_sync_literal = 0;
 528                 break;
 529             default:
 530                 goto invalid;
 531             }
 532             break;
 533
 534         case sw_literal_argument:
 535             if (s->literal_len && --s->literal_len) {
 536                 break;
 537             }
 538
 539             arg = ngx_array_push(&s->args);
 540             if (arg == NULL) {
 541                 return NGX_ERROR;
 542             }
 543             arg->len = p + 1 - s->arg_start;
 544             arg->data = s->arg_start;
 545             s->arg_start = NULL;
 546             state = sw_end_literal_argument;
 547
 548             break;
 549
 550         case sw_end_literal_argument:
 551             switch (ch) {
 552             case '{':
 553                 if (s->args.nelts <= 2) {
 554                     state = sw_literal;
 555                     break;
 556                 }
 557                 goto invalid;
 558             case CR:
 559                 state = sw_almost_done;
 560                 break;
 561             case LF:
 562                 goto done;
 563             default:
 564                 state = sw_spaces_before_argument;
 565                 break;
 566             }
 567             break;
 568
 569         case sw_almost_done:
 570             switch (ch) {
 571             case LF:
 572                 goto done;
 573             default:
 574                 goto invalid;
 575             }
 576         }
 577     }
 578
 579     s->buffer->pos = p;
 580     s->state = state;
 581
 582     return NGX_AGAIN;
 583
 584 done:
 585
 586     s->buffer->pos = p + 1;
 587
 588     if (s->arg_start) {
 589         arg = ngx_array_push(&s->args);
 590         if (arg == NULL) {
 591             return NGX_ERROR;
 592         }
 593         arg->len = s->arg_end - s->arg_start;
 594         arg->data = s->arg_start;
 595
 596         s->arg_start = NULL;
 597         s->cmd_start = NULL;
 598         s->quoted = 0;
 599         s->no_sync_literal = 0;
 600         s->literal_len = 0;
 601     }
 602
 603     s->state = (s->command != NGX_IMAP_AUTHENTICATE) ? sw_start : sw_argument;
 604
 605     return NGX_OK;
 606
 607 invalid:
 608
 609     s->state = sw_start;
 610     s->quoted = 0;
 611     s->no_sync_literal = 0;
 612     s->literal_len = 0;
 613
 614     return NGX_MAIL_PARSE_INVALID_COMMAND;
 615 }
 616
 617
 618 ngx_int_t
 619 ngx_mail_smtp_parse_command(ngx_mail_session_t *s)
 620 {
 621     u_char      ch, *p, *c, c0, c1, c2, c3;
 622     ngx_str_t  *arg;
 623     enum {
 624         sw_start = 0,
 625         sw_spaces_before_argument,
 626         sw_argument,
 627         sw_almost_done
 628     } state;
 629
 630     state = s->state;
 631
 632     for (p = s->buffer->pos; p < s->buffer->last; p++) {
 633         ch = *p;
 634
 635         switch (state) {
 636
 637         /* SMTP command */
 638         case sw_start:
 639             if (ch == ' ' || ch == CR || ch == LF) {
 640                 c = s->buffer->start;
 641
 642                 if (p - c == 4) {
 643
 644                     c0 = ngx_toupper(c[0]);
 645                     c1 = ngx_toupper(c[1]);
 646                     c2 = ngx_toupper(c[2]);
 647                     c3 = ngx_toupper(c[3]);
 648
 649                     if (c0 == 'H' && c1 == 'E' && c2 == 'L' && c3 == 'O')
 650                     {
 651                         s->command = NGX_SMTP_HELO;
 652
 653                     } else if (c0 == 'E' && c1 == 'H' && c2 == 'L' && c3 == 'O')
 654                     {
 655                         s->command = NGX_SMTP_EHLO;
 656
 657                     } else if (c0 == 'Q' && c1 == 'U' && c2 == 'I' && c3 == 'T')
 658                     {
 659                         s->command = NGX_SMTP_QUIT;
 660
 661                     } else if (c0 == 'A' && c1 == 'U' && c2 == 'T' && c3 == 'H')
 662                     {
 663                         s->command = NGX_SMTP_AUTH;
 664
 665                     } else if (c0 == 'N' && c1 == 'O' && c2 == 'O' && c3 == 'P')
 666                     {
 667                         s->command = NGX_SMTP_NOOP;
 668
 669                     } else if (c0 == 'M' && c1 == 'A' && c2 == 'I' && c3 == 'L')
 670                     {
 671                         s->command = NGX_SMTP_MAIL;
 672
 673                     } else if (c0 == 'R' && c1 == 'S' && c2 == 'E' && c3 == 'T')
 674                     {
 675                         s->command = NGX_SMTP_RSET;
 676
 677                     } else if (c0 == 'R' && c1 == 'C' && c2 == 'P' && c3 == 'T')
 678                     {
 679                         s->command = NGX_SMTP_RCPT;
 680
 681                     } else if (c0 == 'V' && c1 == 'R' && c2 == 'F' && c3 == 'Y')
 682                     {
 683                         s->command = NGX_SMTP_VRFY;
 684
 685                     } else if (c0 == 'E' && c1 == 'X' && c2 == 'P' && c3 == 'N')
 686                     {
 687                         s->command = NGX_SMTP_EXPN;
 688
 689                     } else if (c0 == 'H' && c1 == 'E' && c2 == 'L' && c3 == 'P')
 690                     {
 691                         s->command = NGX_SMTP_HELP;
 692
 693                     } else {
 694                         goto invalid;
 695                     }
 696 #if (NGX_MAIL_SSL)
 697                 } else if (p - c == 8) {
 698
 699                     if ((c[0] == 'S'|| c[0] == 's')
 700                         && (c[1] == 'T'|| c[1] == 't')
 701                         && (c[2] == 'A'|| c[2] == 'a')
 702                         && (c[3] == 'R'|| c[3] == 'r')
 703                         && (c[4] == 'T'|| c[4] == 't')
 704                         && (c[5] == 'T'|| c[5] == 't')
 705                         && (c[6] == 'L'|| c[6] == 'l')
 706                         && (c[7] == 'S'|| c[7] == 's'))
 707                     {
 708                         s->command = NGX_SMTP_STARTTLS;
 709
 710                     } else {
 711                         goto invalid;
 712                     }
 713 #endif
 714                 } else {
 715                     goto invalid;
 716                 }
 717
 718                 switch (ch) {
 719                 case ' ':
 720                     state = sw_spaces_before_argument;
 721                     break;
 722                 case CR:
 723                     state = sw_almost_done;
 724                     break;
 725                 case LF:
 726                     goto done;
 727                 }
 728                 break;
 729             }
 730
 731             if ((ch < 'A' || ch > 'Z') && (ch < 'a' || ch > 'z')) {
 732                 goto invalid;
 733             }
 734
 735             break;
 736
 737         case sw_spaces_before_argument:
 738             switch (ch) {
 739             case ' ':
 740                 break;
 741             case CR:
 742                 state = sw_almost_done;
 743                 s->arg_end = p;
 744                 break;
 745             case LF:
 746                 s->arg_end = p;
 747                 goto done;
 748             default:
 749                 if (s->args.nelts <= 10) {
 750                     state = sw_argument;
 751                     s->arg_start = p;
 752                     break;
 753                 }
 754                 goto invalid;
 755             }
 756             break;
 757
 758         case sw_argument:
 759             switch (ch) {
 760             case ' ':
 761             case CR:
 762             case LF:
 763                 arg = ngx_array_push(&s->args);
 764                 if (arg == NULL) {
 765                     return NGX_ERROR;
 766                 }
 767                 arg->len = p - s->arg_start;
 768                 arg->data = s->arg_start;
 769                 s->arg_start = NULL;
 770
 771                 switch (ch) {
 772                 case ' ':
 773                     state = sw_spaces_before_argument;
 774                     break;
 775                 case CR:
 776                     state = sw_almost_done;
 777                     break;
 778                 case LF:
 779                     goto done;
 780                 }
 781                 break;
 782
 783             default:
 784                 break;
 785             }
 786             break;
 787
 788         case sw_almost_done:
 789             switch (ch) {
 790             case LF:
 791                 goto done;
 792             default:
 793                 goto invalid;
 794             }
 795         }
 796     }
 797
 798     s->buffer->pos = p;
 799     s->state = state;
 800
 801     return NGX_AGAIN;
 802
 803 done:
 804
 805     s->buffer->pos = p + 1;
 806
 807     if (s->arg_start) {
 808         arg = ngx_array_push(&s->args);
 809         if (arg == NULL) {
 810             return NGX_ERROR;
 811         }
 812         arg->len = s->arg_end - s->arg_start;
 813         arg->data = s->arg_start;
 814         s->arg_start = NULL;
 815     }
 816
 817     s->state = (s->command != NGX_SMTP_AUTH) ? sw_start : sw_argument;
 818
 819     return NGX_OK;
 820
 821 invalid:
 822
 823     s->state = sw_start;
 824     s->arg_start = NULL;
 825
 826     return NGX_MAIL_PARSE_INVALID_COMMAND;
 827 }
 828
 829
 830 ngx_int_t
 831 ngx_mail_auth_parse(ngx_mail_session_t *s, ngx_connection_t *c)
 832 {
 833     ngx_str_t                 *arg;
 834
 835 #if (NGX_MAIL_SSL)
 836     if (ngx_mail_starttls_only(s, c)) {
 837         return NGX_MAIL_PARSE_INVALID_COMMAND;
 838     }
 839 #endif
 840
 841     arg = s->args.elts;
 842
 843     if (arg[0].len == 5) {
 844
 845         if (ngx_strncasecmp(arg[0].data, (u_char *) "LOGIN", 5) == 0) {
 846
 847             if (s->args.nelts == 1) {
 848                 return NGX_MAIL_AUTH_LOGIN;
 849             }
 850
 851             return NGX_MAIL_PARSE_INVALID_COMMAND;
 852         }
 853
 854         if (ngx_strncasecmp(arg[0].data, (u_char *) "PLAIN", 5) == 0) {
 855
 856             if (s->args.nelts == 1) {
 857                 return NGX_MAIL_AUTH_PLAIN;
 858             }
 859
 860             if (s->args.nelts == 2) {
 861                 return ngx_mail_auth_plain(s, c, 1);
 862             }
 863         }
 864
 865         return NGX_MAIL_PARSE_INVALID_COMMAND;
 866     }
 867
 868     if (arg[0].len == 8) {
 869
 870         if (s->args.nelts != 1) {
 871             return NGX_MAIL_PARSE_INVALID_COMMAND;
 872         }
 873
 874         if (ngx_strncasecmp(arg[0].data, (u_char *) "CRAM-MD5", 8) == 0) {
 875             return NGX_MAIL_AUTH_CRAM_MD5;
 876         }
 877     }
 878
 879     return NGX_MAIL_PARSE_INVALID_COMMAND;
 880 }