Mercurial > hg > nginx
view src/mail/ngx_mail_parse.c @ 6749:f88a145b093e stable-1.10
HTTP/2: the "421 Misdirected Request" response (closes #848).
Since 4fbef397c753 nginx rejects with the 400 error any attempts of
requesting different host over the same connection, if the relevant
virtual server requires verification of a client certificate.
While requesting hosts other than negotiated isn't something legal
in HTTP/1.x, the HTTP/2 specification explicitly permits such requests
for connection reuse and has introduced a special response code 421.
According to RFC 7540 Section 9.1.2 this code can be sent by a server
that is not configured to produce responses for the combination of
scheme and authority that are included in the request URI. And the
client may retry the request over a different connection.
Now this code is used for requests that aren't authorized in current
connection. After receiving the 421 response a client will be able
to open a new connection, provide the required certificate and retry
the request.
Unfortunately, not all clients currently are able to handle it well.
Notably Chrome just shows an error, while at least the latest version
of Firefox retries the request over a new connection.
| author | Valentin Bartenev <vbart@nginx.com> |
|---|---|
| date | Fri, 20 May 2016 18:41:17 +0300 |
| parents | 04e43d03e153 |
| children | bcb107bb89cd |
line wrap: on
line source
/* * 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 (s->args.nelts != 1) { return NGX_MAIL_PARSE_INVALID_COMMAND; } if (ngx_strncasecmp(arg[0].data, (u_char *) "CRAM-MD5", 8) == 0) { return NGX_MAIL_AUTH_CRAM_MD5; } } return NGX_MAIL_PARSE_INVALID_COMMAND; }