Mercurial > hg > nginx
view src/mail/ngx_mail_parse.c @ 7694:09fb2135a589
SSL: fixed shutdown handling.
Previously, bidirectional shutdown never worked, due to two issues
in the code:
1. The code only tested SSL_ERROR_WANT_READ and SSL_ERROR_WANT_WRITE
when there was an error in the error queue, which cannot happen.
The bug was introduced in an attempt to fix unexpected error logging
as reported with OpenSSL 0.9.8g
(http://mailman.nginx.org/pipermail/nginx/2008-January/003084.html).
2. The code never called SSL_shutdown() for the second time to wait for
the peer's close_notify alert.
This change fixes both issues.
Note that after this change bidirectional shutdown is expected to work for
the first time, so c->ssl->no_wait_shutdown now makes a difference. This
is not a problem for HTTP code which always uses c->ssl->no_wait_shutdown,
but might be a problem for stream and mail code, as well as 3rd party
modules.
To minimize the effect of the change, the timeout, which was used to be 30
seconds and not configurable, though never actually used, is now set to
3 seconds. It is also expanded to apply to both SSL_ERROR_WANT_READ and
SSL_ERROR_WANT_WRITE, so timeout is properly set if writing to the socket
buffer is not possible.
| author | Maxim Dounin <mdounin@mdounin.ru> |
|---|---|
| date | Mon, 10 Aug 2020 18:52:09 +0300 |
| parents | bcb107bb89cd |
| children | 6a81d96d3733 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_mail.h> #include <ngx_mail_pop3_module.h> #include <ngx_mail_imap_module.h> #include <ngx_mail_smtp_module.h> ngx_int_t ngx_mail_pop3_parse_command(ngx_mail_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 == 'A' && c1 == 'P' && c2 == 'O' && c3 == 'P') { s->command = NGX_POP3_APOP; } 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 == 'A' && c1 == 'U' && c2 == 'T' && c3 == 'H') { s->command = NGX_POP3_AUTH; } else if (c0 == 'N' && c1 == 'O' && c2 == 'O' && c3 == 'P') { s->command = NGX_POP3_NOOP; #if (NGX_MAIL_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) { case ' ': /* * the space should be considered as part of the at username * or password, but not of argument in other commands */ if (s->command == NGX_POP3_USER || s->command == NGX_POP3_PASS) { break; } /* fall through */ 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 = (s->command != NGX_POP3_AUTH) ? sw_start : sw_argument; return NGX_OK; invalid: s->state = sw_start; s->arg_start = NULL; return NGX_MAIL_PARSE_INVALID_COMMAND; } ngx_int_t ngx_mail_imap_parse_command(ngx_mail_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_MAIL_PARSE_INVALID_COMMAND; case LF: s->state = sw_start; return NGX_MAIL_PARSE_INVALID_COMMAND; } break; case sw_spaces_before_command: switch (ch) { case ' ': break; case CR: s->state = sw_start; return NGX_MAIL_PARSE_INVALID_COMMAND; case LF: s->state = sw_start; return NGX_MAIL_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_MAIL_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; case 12: if ((c[0] == 'A'|| c[0] == 'a') && (c[1] == 'U'|| c[1] == 'u') && (c[2] == 'T'|| c[2] == 't') && (c[3] == 'H'|| c[3] == 'h') && (c[4] == 'E'|| c[4] == 'e') && (c[5] == 'N'|| c[5] == 'n') && (c[6] == 'T'|| c[6] == 't') && (c[7] == 'I'|| c[7] == 'i') && (c[8] == 'C'|| c[8] == 'c') && (c[9] == 'A'|| c[9] == 'a') && (c[10] == 'T'|| c[10] == 't') && (c[11] == 'E'|| c[11] == 'e')) { s->command = NGX_IMAP_AUTHENTICATE; } 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: if (ch == ' ' && s->quoted) { break; } 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 = (s->command != NGX_IMAP_AUTHENTICATE) ? sw_start : sw_argument; return NGX_OK; invalid: s->state = sw_start; s->quoted = 0; s->no_sync_literal = 0; s->literal_len = 0; return NGX_MAIL_PARSE_INVALID_COMMAND; } ngx_int_t ngx_mail_smtp_parse_command(ngx_mail_session_t *s) { u_char ch, *p, *c, c0, c1, c2, c3; ngx_str_t *arg; enum { sw_start = 0, sw_command, sw_invalid, 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) { /* SMTP command */ case sw_start: s->cmd_start = p; state = sw_command; /* fall through */ case sw_command: if (ch == ' ' || ch == CR || ch == LF) { c = s->cmd_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 == 'H' && c1 == 'E' && c2 == 'L' && c3 == 'O') { s->command = NGX_SMTP_HELO; } else if (c0 == 'E' && c1 == 'H' && c2 == 'L' && c3 == 'O') { s->command = NGX_SMTP_EHLO; } else if (c0 == 'Q' && c1 == 'U' && c2 == 'I' && c3 == 'T') { s->command = NGX_SMTP_QUIT; } else if (c0 == 'A' && c1 == 'U' && c2 == 'T' && c3 == 'H') { s->command = NGX_SMTP_AUTH; } else if (c0 == 'N' && c1 == 'O' && c2 == 'O' && c3 == 'P') { s->command = NGX_SMTP_NOOP; } else if (c0 == 'M' && c1 == 'A' && c2 == 'I' && c3 == 'L') { s->command = NGX_SMTP_MAIL; } else if (c0 == 'R' && c1 == 'S' && c2 == 'E' && c3 == 'T') { s->command = NGX_SMTP_RSET; } else if (c0 == 'R' && c1 == 'C' && c2 == 'P' && c3 == 'T') { s->command = NGX_SMTP_RCPT; } else if (c0 == 'V' && c1 == 'R' && c2 == 'F' && c3 == 'Y') { s->command = NGX_SMTP_VRFY; } else if (c0 == 'E' && c1 == 'X' && c2 == 'P' && c3 == 'N') { s->command = NGX_SMTP_EXPN; } else if (c0 == 'H' && c1 == 'E' && c2 == 'L' && c3 == 'P') { s->command = NGX_SMTP_HELP; } else { goto invalid; } #if (NGX_MAIL_SSL) } else if (p - c == 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_SMTP_STARTTLS; } else { goto invalid; } #endif } else { goto invalid; } s->cmd.data = s->cmd_start; s->cmd.len = p - s->cmd_start; 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_invalid: goto invalid; 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 <= 10) { state = sw_argument; s->arg_start = p; break; } goto invalid; } break; case sw_argument: switch (ch) { 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 = (s->command != NGX_SMTP_AUTH) ? sw_start : sw_argument; return NGX_OK; invalid: s->state = sw_invalid; s->arg_start = NULL; /* skip invalid command till LF */ for (p = s->buffer->pos; p < s->buffer->last; p++) { if (*p == LF) { s->state = sw_start; p++; break; } } s->buffer->pos = p; return NGX_MAIL_PARSE_INVALID_COMMAND; } ngx_int_t ngx_mail_auth_parse(ngx_mail_session_t *s, ngx_connection_t *c) { ngx_str_t *arg; #if (NGX_MAIL_SSL) if (ngx_mail_starttls_only(s, c)) { return NGX_MAIL_PARSE_INVALID_COMMAND; } #endif if (s->args.nelts == 0) { return NGX_MAIL_PARSE_INVALID_COMMAND; } arg = s->args.elts; if (arg[0].len == 5) { if (ngx_strncasecmp(arg[0].data, (u_char *) "LOGIN", 5) == 0) { if (s->args.nelts == 1) { return NGX_MAIL_AUTH_LOGIN; } if (s->args.nelts == 2) { return NGX_MAIL_AUTH_LOGIN_USERNAME; } return NGX_MAIL_PARSE_INVALID_COMMAND; } if (ngx_strncasecmp(arg[0].data, (u_char *) "PLAIN", 5) == 0) { if (s->args.nelts == 1) { return NGX_MAIL_AUTH_PLAIN; } if (s->args.nelts == 2) { return ngx_mail_auth_plain(s, c, 1); } } return NGX_MAIL_PARSE_INVALID_COMMAND; } if (arg[0].len == 8) { if (ngx_strncasecmp(arg[0].data, (u_char *) "CRAM-MD5", 8) == 0) { if (s->args.nelts != 1) { return NGX_MAIL_PARSE_INVALID_COMMAND; } return NGX_MAIL_AUTH_CRAM_MD5; } if (ngx_strncasecmp(arg[0].data, (u_char *) "EXTERNAL", 8) == 0) { if (s->args.nelts == 1) { return NGX_MAIL_AUTH_EXTERNAL; } if (s->args.nelts == 2) { return ngx_mail_auth_external(s, c, 1); } } return NGX_MAIL_PARSE_INVALID_COMMAND; } return NGX_MAIL_PARSE_INVALID_COMMAND; }