Mercurial > hg > nginx
view src/mail/ngx_mail_smtp_module.c @ 7836:6a81d96d3733
Mail: fixed handling of invalid SMTP commands split between reads.
Previously, if an invalid SMTP command was split between reads, nginx failed
to wait for LF before returning an error, and interpreted the rest of the
command received later as a separate command.
The sw_invalid state in ngx_mail_smtp_parse_command(), introduced in
04e43d03e153, did not work, since ngx_mail_smtp_auth_state() clears
s->state when returning an error due to NGX_MAIL_PARSE_INVALID_COMMAND.
And not clearing s->state will introduce another problem: the rest
of the command would trigger duplicate error when rest of the command is
received.
Fix is to return NGX_AGAIN from ngx_mail_smtp_parse_command() until full
command is received.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 19 May 2021 03:13:15 +0300 |
parents | f18c285c2e59 |
children | dc955d274130 |
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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_smtp_module.h> static void *ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf); static char *ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_conf_bitmask_t ngx_mail_smtp_auth_methods[] = { { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED }, { ngx_string("login"), NGX_MAIL_AUTH_LOGIN_ENABLED }, { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED }, { ngx_string("external"), NGX_MAIL_AUTH_EXTERNAL_ENABLED }, { ngx_string("none"), NGX_MAIL_AUTH_NONE_ENABLED }, { ngx_null_string, 0 } }; static ngx_str_t ngx_mail_smtp_auth_methods_names[] = { ngx_string("PLAIN"), ngx_string("LOGIN"), ngx_null_string, /* APOP */ ngx_string("CRAM-MD5"), ngx_string("EXTERNAL"), ngx_null_string /* NONE */ }; static ngx_mail_protocol_t ngx_mail_smtp_protocol = { ngx_string("smtp"), { 25, 465, 587, 0 }, NGX_MAIL_SMTP_PROTOCOL, ngx_mail_smtp_init_session, ngx_mail_smtp_init_protocol, ngx_mail_smtp_parse_command, ngx_mail_smtp_auth_state, ngx_string("451 4.3.2 Internal server error" CRLF), ngx_string("421 4.7.1 SSL certificate error" CRLF), ngx_string("421 4.7.1 No required SSL certificate" CRLF) }; static ngx_command_t ngx_mail_smtp_commands[] = { { ngx_string("smtp_client_buffer"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_smtp_srv_conf_t, client_buffer_size), NULL }, { ngx_string("smtp_greeting_delay"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_smtp_srv_conf_t, greeting_delay), NULL }, { ngx_string("smtp_capabilities"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_mail_capabilities, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_smtp_srv_conf_t, capabilities), NULL }, { ngx_string("smtp_auth"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_conf_set_bitmask_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_smtp_srv_conf_t, auth_methods), &ngx_mail_smtp_auth_methods }, ngx_null_command }; static ngx_mail_module_t ngx_mail_smtp_module_ctx = { &ngx_mail_smtp_protocol, /* protocol */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_mail_smtp_create_srv_conf, /* create server configuration */ ngx_mail_smtp_merge_srv_conf /* merge server configuration */ }; ngx_module_t ngx_mail_smtp_module = { NGX_MODULE_V1, &ngx_mail_smtp_module_ctx, /* module context */ ngx_mail_smtp_commands, /* module directives */ NGX_MAIL_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void * ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf) { ngx_mail_smtp_srv_conf_t *sscf; sscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_smtp_srv_conf_t)); if (sscf == NULL) { return NULL; } sscf->client_buffer_size = NGX_CONF_UNSET_SIZE; sscf->greeting_delay = NGX_CONF_UNSET_MSEC; if (ngx_array_init(&sscf->capabilities, cf->pool, 4, sizeof(ngx_str_t)) != NGX_OK) { return NULL; } return sscf; } static char * ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_mail_smtp_srv_conf_t *prev = parent; ngx_mail_smtp_srv_conf_t *conf = child; u_char *p, *auth, *last; size_t size; ngx_str_t *c; ngx_uint_t i, m, auth_enabled; ngx_mail_core_srv_conf_t *cscf; ngx_conf_merge_size_value(conf->client_buffer_size, prev->client_buffer_size, (size_t) ngx_pagesize); ngx_conf_merge_msec_value(conf->greeting_delay, prev->greeting_delay, 0); ngx_conf_merge_bitmask_value(conf->auth_methods, prev->auth_methods, (NGX_CONF_BITMASK_SET |NGX_MAIL_AUTH_PLAIN_ENABLED |NGX_MAIL_AUTH_LOGIN_ENABLED)); cscf = ngx_mail_conf_get_module_srv_conf(cf, ngx_mail_core_module); size = sizeof("220 ESMTP ready" CRLF) - 1 + cscf->server_name.len; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->greeting.len = size; conf->greeting.data = p; *p++ = '2'; *p++ = '2'; *p++ = '0'; *p++ = ' '; p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len); ngx_memcpy(p, " ESMTP ready" CRLF, sizeof(" ESMTP ready" CRLF) - 1); size = sizeof("250 " CRLF) - 1 + cscf->server_name.len; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->server_name.len = size; conf->server_name.data = p; *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' '; p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len); *p++ = CR; *p = LF; if (conf->capabilities.nelts == 0) { conf->capabilities = prev->capabilities; } size = sizeof("250-") - 1 + cscf->server_name.len + sizeof(CRLF) - 1; c = conf->capabilities.elts; for (i = 0; i < conf->capabilities.nelts; i++) { size += sizeof("250 ") - 1 + c[i].len + sizeof(CRLF) - 1; } auth_enabled = 0; for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (m & conf->auth_methods) { size += 1 + ngx_mail_smtp_auth_methods_names[i].len; auth_enabled = 1; } } if (auth_enabled) { size += sizeof("250 AUTH") - 1 + sizeof(CRLF) - 1; } p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->capability.len = size; conf->capability.data = p; last = p; *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-'; p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len); *p++ = CR; *p++ = LF; for (i = 0; i < conf->capabilities.nelts; i++) { last = p; *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-'; p = ngx_cpymem(p, c[i].data, c[i].len); *p++ = CR; *p++ = LF; } auth = p; if (auth_enabled) { last = p; *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' '; *p++ = 'A'; *p++ = 'U'; *p++ = 'T'; *p++ = 'H'; for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (m & conf->auth_methods) { *p++ = ' '; p = ngx_cpymem(p, ngx_mail_smtp_auth_methods_names[i].data, ngx_mail_smtp_auth_methods_names[i].len); } } *p++ = CR; *p = LF; } else { last[3] = ' '; } size += sizeof("250 STARTTLS" CRLF) - 1; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_capability.len = size; conf->starttls_capability.data = p; p = ngx_cpymem(p, conf->capability.data, conf->capability.len); ngx_memcpy(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1); p = conf->starttls_capability.data + (last - conf->capability.data) + 3; *p = '-'; size = (auth - conf->capability.data) + sizeof("250 STARTTLS" CRLF) - 1; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_only_capability.len = size; conf->starttls_only_capability.data = p; p = ngx_cpymem(p, conf->capability.data, auth - conf->capability.data); ngx_memcpy(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1); if (last < auth) { p = conf->starttls_only_capability.data + (last - conf->capability.data) + 3; *p = '-'; } return NGX_CONF_OK; }