Mercurial > hg > nginx-quic
view src/mail/ngx_mail_smtp_module.c @ 7377:d4448892a294
HTTP/2: flood detection.
Fixed uncontrolled memory growth in case peer is flooding us with
some frames (e.g., SETTINGS and PING) and doesn't read data. Fix
is to limit the number of allocated control frames.
author | Ruslan Ermilov <ru@nginx.com> |
---|---|
date | Tue, 06 Nov 2018 16:29:35 +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; }