view src/imap/ngx_imap_parse.c @ 196:8759b346e431 NGINX_0_3_45

nginx 0.3.45 *) Feature: the "ssl_verify_client", "ssl_verify_depth", and "ssl_client_certificate" directives. *) Change: the $request_method variable now returns the main request method. *) Change: the ° symbol codes were changed in koi-win conversion table. *) Feature: the euro É N symbols were added to koi-win conversion table. *) Bugfix: if nginx distributed the requests among several backends and some backend failed, then requests intended for this backend was directed to one live backend only instead of being distributed among the rest.
author Igor Sysoev <http://sysoev.ru>
date Sat, 06 May 2006 00:00:00 +0400
parents 91372f004adf
children fbf2b2f66c9f
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <ngx_imap.h>


ngx_int_t ngx_imap_parse_command(ngx_imap_session_t *s)
{
    u_char      ch, *p, *c;
    ngx_str_t  *arg;
    enum {
        sw_start = 0,
        sw_spaces_before_command,
        sw_command,
        sw_spaces_before_argument,
        sw_argument,
        sw_backslash,
        sw_literal,
        sw_no_sync_literal_argument,
        sw_start_literal_argument,
        sw_literal_argument,
        sw_end_literal_argument,
        sw_almost_done
    } state;

    state = s->state;

    for (p = s->buffer->pos; p < s->buffer->last; p++) {
        ch = *p;

        switch (state) {

        /* IMAP tag */
        case sw_start:
            switch (ch) {
            case ' ':
                s->tag.len = p - s->buffer->start + 1;
                s->tag.data = s->buffer->start;
                state = sw_spaces_before_command;
                break;
            case CR:
                s->state = sw_start;
                return NGX_IMAP_PARSE_INVALID_COMMAND;
            case LF:
                s->state = sw_start;
                return NGX_IMAP_PARSE_INVALID_COMMAND;
            }
            break;

        case sw_spaces_before_command:
            switch (ch) {
            case ' ':
                break;
            case CR:
                s->state = sw_start;
                return NGX_IMAP_PARSE_INVALID_COMMAND;
            case LF:
                s->state = sw_start;
                return NGX_IMAP_PARSE_INVALID_COMMAND;
            default:
                s->cmd_start = p;
                state = sw_command;
                break;
            }
            break;

        case sw_command:
            if (ch == ' ' || ch == CR || ch == LF) {

                c = s->cmd_start;

                switch (p - c) {

                case 4:
                    if ((c[0] == 'N' || c[0] == 'n')
                        && (c[1] == 'O'|| c[1] == 'o')
                        && (c[2] == 'O'|| c[2] == 'o')
                        && (c[3] == 'P'|| c[3] == 'p'))
                    {
                        s->command = NGX_IMAP_NOOP;

                    } else {
                        goto invalid;
                    }
                    break;

                case 5:
                    if ((c[0] == 'L'|| c[0] == 'l')
                        && (c[1] == 'O'|| c[1] == 'o')
                        && (c[2] == 'G'|| c[2] == 'g')
                        && (c[3] == 'I'|| c[3] == 'i')
                        && (c[4] == 'N'|| c[4] == 'n'))
                    {
                        s->command = NGX_IMAP_LOGIN;

                    } else {
                        goto invalid;
                    }
                    break;

                case 6:
                    if ((c[0] == 'L'|| c[0] == 'l')
                        && (c[1] == 'O'|| c[1] == 'o')
                        && (c[2] == 'G'|| c[2] == 'g')
                        && (c[3] == 'O'|| c[3] == 'o')
                        && (c[4] == 'U'|| c[4] == 'u')
                        && (c[5] == 'T'|| c[5] == 't'))
                    {
                        s->command = NGX_IMAP_LOGOUT;

                    } else {
                        goto invalid;
                    }
                    break;

#if (NGX_IMAP_SSL)
                case 8:
                    if ((c[0] == 'S'|| c[0] == 's')
                        && (c[1] == 'T'|| c[1] == 't')
                        && (c[2] == 'A'|| c[2] == 'a')
                        && (c[3] == 'R'|| c[3] == 'r')
                        && (c[4] == 'T'|| c[4] == 't')
                        && (c[5] == 'T'|| c[5] == 't')
                        && (c[6] == 'L'|| c[6] == 'l')
                        && (c[7] == 'S'|| c[7] == 's'))
                    {
                        s->command = NGX_IMAP_STARTTLS;

                    } else {
                        goto invalid;
                    }
                    break;
#endif

                case 10:
                    if ((c[0] == 'C'|| c[0] == 'c')
                        && (c[1] == 'A'|| c[1] == 'a')
                        && (c[2] == 'P'|| c[2] == 'p')
                        && (c[3] == 'A'|| c[3] == 'a')
                        && (c[4] == 'B'|| c[4] == 'b')
                        && (c[5] == 'I'|| c[5] == 'i')
                        && (c[6] == 'L'|| c[6] == 'l')
                        && (c[7] == 'I'|| c[7] == 'i')
                        && (c[8] == 'T'|| c[8] == 't')
                        && (c[9] == 'Y'|| c[9] == 'y'))
                    {
                        s->command = NGX_IMAP_CAPABILITY;

                    } else {
                        goto invalid;
                    }
                    break;

                default:
                    goto invalid;
                }

                switch (ch) {
                case ' ':
                    state = sw_spaces_before_argument;
                    break;
                case CR:
                    state = sw_almost_done;
                    break;
                case LF:
                    goto done;
                }
                break;
            }

            if ((ch < 'A' || ch > 'Z') && (ch < 'a' || ch > 'z')) {
                goto invalid;
            }

            break;

        case sw_spaces_before_argument:
            switch (ch) {
            case ' ':
                break;
            case CR:
                state = sw_almost_done;
                s->arg_end = p;
                break;
            case LF:
                s->arg_end = p;
                goto done;
            case '"':
                if (s->args.nelts <= 2) {
                    s->quoted = 1;
                    s->arg_start = p + 1;
                    state = sw_argument;
                    break;
                }
                goto invalid;
            case '{':
                if (s->args.nelts <= 2) {
                    state = sw_literal;
                    break;
                }
                goto invalid;
            default:
                if (s->args.nelts <= 2) {
                    s->arg_start = p;
                    state = sw_argument;
                    break;
                }
                goto invalid;
            }
            break;

        case sw_argument:
            switch (ch) {
            case '"':
                if (!s->quoted) {
                    break;
                }
                s->quoted = 0;
                /* fall through */
            case ' ':
            case CR:
            case LF:
                arg = ngx_array_push(&s->args);
                if (arg == NULL) {
                    return NGX_ERROR;
                }
                arg->len = p - s->arg_start;
                arg->data = s->arg_start;
                s->arg_start = NULL;

                switch (ch) {
                case '"':
                case ' ':
                    state = sw_spaces_before_argument;
                    break;
                case CR:
                    state = sw_almost_done;
                    break;
                case LF:
                    goto done;
                }
                break;
            case '\\':
                if (s->quoted) {
                    s->backslash = 1;
                    state = sw_backslash;
                }
                break;
            }
            break;

        case sw_backslash:
            switch (ch) {
            case CR:
            case LF:
                goto invalid;
            default:
                state = sw_argument;
            }
            break;

        case sw_literal:
            if (ch >= '0' && ch <= '9') {
                s->literal_len = s->literal_len * 10 + (ch - '0');
                break;
            }
            if (ch == '}') {
                state = sw_start_literal_argument;
                break;
            }
            if (ch == '+') {
                state = sw_no_sync_literal_argument;
                break;
            }
            goto invalid;

        case sw_no_sync_literal_argument:
            if (ch == '}') {
                s->no_sync_literal = 1;
                state = sw_start_literal_argument;
                break;
            }
            goto invalid;

        case sw_start_literal_argument:
            switch (ch) {
            case CR:
                break;
            case LF:
                s->buffer->pos = p + 1;
                s->arg_start = p + 1;
                if (s->no_sync_literal == 0) {
                    s->state = sw_literal_argument;
                    return NGX_IMAP_NEXT;
                }
                state = sw_literal_argument;
                s->no_sync_literal = 0;
                break;
            default:
                goto invalid;
            }
            break;

        case sw_literal_argument:
            if (s->literal_len && --s->literal_len) {
                break;
            }

            arg = ngx_array_push(&s->args);
            if (arg == NULL) {
                return NGX_ERROR;
            }
            arg->len = p + 1 - s->arg_start;
            arg->data = s->arg_start;
            s->arg_start = NULL;
            state = sw_end_literal_argument;

            break;

        case sw_end_literal_argument:
            switch (ch) {
            case '{':
                if (s->args.nelts <= 2) {
                    state = sw_literal;
                    break;
                }
                goto invalid;
            case CR:
                state = sw_almost_done;
                break;
            case LF:
                goto done;
            default:
                state = sw_spaces_before_argument;
                break;
            }
            break;

        case sw_almost_done:
            switch (ch) {
            case LF:
                goto done;
            default:
                goto invalid;
            }
        }
    }

    s->buffer->pos = p;
    s->state = state;

    return NGX_AGAIN;

done:

    s->buffer->pos = p + 1;

    if (s->arg_start) {
        arg = ngx_array_push(&s->args);
        if (arg == NULL) {
            return NGX_ERROR;
        }
        arg->len = s->arg_end - s->arg_start;
        arg->data = s->arg_start;

        s->arg_start = NULL;
        s->cmd_start = NULL;
        s->quoted = 0;
        s->no_sync_literal = 0;
        s->literal_len = 0;
    }

    s->state = sw_start;

    return NGX_OK;

invalid:

    s->state = sw_start;
    s->quoted = 0;
    s->no_sync_literal = 0;
    s->literal_len = 0;

    return NGX_IMAP_PARSE_INVALID_COMMAND;
}


ngx_int_t ngx_pop3_parse_command(ngx_imap_session_t *s)
{
    u_char      ch, *p, *c, c0, c1, c2, c3;
    ngx_str_t  *arg;
    enum {
        sw_start = 0,
        sw_spaces_before_argument,
        sw_argument,
        sw_almost_done
    } state;

    state = s->state;

    for (p = s->buffer->pos; p < s->buffer->last; p++) {
        ch = *p;

        switch (state) {

        /* POP3 command */
        case sw_start:
            if (ch == ' ' || ch == CR || ch == LF) {
                c = s->buffer->start;

                if (p - c == 4) {

                    c0 = ngx_toupper(c[0]);
                    c1 = ngx_toupper(c[1]);
                    c2 = ngx_toupper(c[2]);
                    c3 = ngx_toupper(c[3]);

                    if (c0 == 'U' && c1 == 'S' && c2 == 'E' && c3 == 'R')
                    {
                        s->command = NGX_POP3_USER;

                    } else if (c0 == 'P' && c1 == 'A' && c2 == 'S' && c3 == 'S')
                    {
                        s->command = NGX_POP3_PASS;

                    } else if (c0 == 'Q' && c1 == 'U' && c2 == 'I' && c3 == 'T')
                    {
                        s->command = NGX_POP3_QUIT;

                    } else if (c0 == 'C' && c1 == 'A' && c2 == 'P' && c3 == 'A')
                    {
                        s->command = NGX_POP3_CAPA;

                    } else if (c0 == 'N' && c1 == 'O' && c2 == 'O' && c3 == 'P')
                    {
                        s->command = NGX_POP3_NOOP;
#if (NGX_IMAP_SSL)
                    } else if (c0 == 'S' && c1 == 'T' && c2 == 'L' && c3 == 'S')
                    {
                        s->command = NGX_POP3_STLS;
#endif
                    } else {
                        goto invalid;
                    }

                } else {
                    goto invalid;
                }

                switch (ch) {
                case ' ':
                    state = sw_spaces_before_argument;
                    break;
                case CR:
                    state = sw_almost_done;
                    break;
                case LF:
                    goto done;
                }
                break;
            }

            if ((ch < 'A' || ch > 'Z') && (ch < 'a' || ch > 'z')) {
                goto invalid;
            }

            break;

        case sw_spaces_before_argument:
            switch (ch) {
            case ' ':
                break;
            case CR:
                state = sw_almost_done;
                s->arg_end = p;
                break;
            case LF:
                s->arg_end = p;
                goto done;
            default:
                if (s->args.nelts <= 2) {
                    state = sw_argument;
                    s->arg_start = p;
                    break;
                }
                goto invalid;
            }
            break;

        case sw_argument:
            switch (ch) {

         /*
          * the space should be considered part of the at username
          * or password, but not of argument in other commands
          *
          * case ' ':
          */

            case CR:
            case LF:
                arg = ngx_array_push(&s->args);
                if (arg == NULL) {
                    return NGX_ERROR;
                }
                arg->len = p - s->arg_start;
                arg->data = s->arg_start;
                s->arg_start = NULL;

                switch (ch) {
                case ' ':
                    state = sw_spaces_before_argument;
                    break;
                case CR:
                    state = sw_almost_done;
                    break;
                case LF:
                    goto done;
                }
                break;

            default:
                break;
            }
            break;

        case sw_almost_done:
            switch (ch) {
            case LF:
                goto done;
            default:
                goto invalid;
            }
        }
    }

    s->buffer->pos = p;
    s->state = state;

    return NGX_AGAIN;

done:

    s->buffer->pos = p + 1;

    if (s->arg_start) {
        arg = ngx_array_push(&s->args);
        if (arg == NULL) {
            return NGX_ERROR;
        }
        arg->len = s->arg_end - s->arg_start;
        arg->data = s->arg_start;
        s->arg_start = NULL;
    }

    s->state = sw_start;

    return NGX_OK;

invalid:

    s->state = sw_start;

    return NGX_IMAP_PARSE_INVALID_COMMAND;
}