diff src/mail/ngx_mail_core_module.c @ 290:f745bf973510 NGINX_0_5_15

nginx 0.5.15 *) Feature: the mail proxy supports authenticated SMTP proxying and the "smtp_auth", "smtp_capablities", and "xclient" directives. Thanks to Anton Yuzhaninov and Maxim Dounin. *) Feature: now the keep-alive connections are closed just after receiving the reconfiguration signal. *) Change: the "imap" and "auth" directives were renamed to the "mail" and "pop3_auth" directives. *) Bugfix: a segmentation fault occurred in worker process if the CRAM-MD5 authentication method was used and the APOP method was disabled. *) Bugfix: if the "starttls only" directive was used in POP3 protocol, then nginx allowed authentication without switching to the SSL mode. *) Bugfix: worker processes did not exit after reconfiguration and did not rotate logs if the eventport method was used. *) Bugfix: a worker process may got caught in an endless loop, if the "ip_hash" directive was used. *) Bugfix: now nginx does not log some alerts if eventport or /dev/poll methods are used.
author Igor Sysoev <http://sysoev.ru>
date Mon, 19 Mar 2007 00:00:00 +0300
parents
children 2ceaee987f37
line wrap: on
line diff
new file mode 100644
--- /dev/null
+++ b/src/mail/ngx_mail_core_module.c
@@ -0,0 +1,772 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+#include <ngx_mail.h>
+
+
+static void *ngx_mail_core_create_main_conf(ngx_conf_t *cf);
+static void *ngx_mail_core_create_srv_conf(ngx_conf_t *cf);
+static char *ngx_mail_core_merge_srv_conf(ngx_conf_t *cf, void *parent,
+    void *child);
+static char *ngx_mail_core_server(ngx_conf_t *cf, ngx_command_t *cmd,
+    void *conf);
+static char *ngx_mail_core_listen(ngx_conf_t *cf, ngx_command_t *cmd,
+    void *conf);
+static char *ngx_mail_core_capability(ngx_conf_t *cf, ngx_command_t *cmd,
+    void *conf);
+
+
+static ngx_conf_enum_t  ngx_mail_core_procotol[] = {
+    { ngx_string("pop3"), NGX_MAIL_POP3_PROTOCOL },
+    { ngx_string("imap"), NGX_MAIL_IMAP_PROTOCOL },
+    { ngx_string("smtp"), NGX_MAIL_SMTP_PROTOCOL },
+    { ngx_null_string, 0 }
+};
+
+
+static ngx_str_t  ngx_pop3_default_capabilities[] = {
+    ngx_string("TOP"),
+    ngx_string("USER"),
+    ngx_string("UIDL"),
+    ngx_null_string
+};
+
+
+static ngx_str_t  ngx_imap_default_capabilities[] = {
+    ngx_string("IMAP4"),
+    ngx_string("IMAP4rev1"),
+    ngx_string("UIDPLUS"),
+    ngx_null_string
+};
+
+
+static ngx_conf_bitmask_t  ngx_pop3_auth_methods[] = {
+    { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED },
+    { ngx_string("apop"), NGX_MAIL_AUTH_APOP_ENABLED },
+    { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED },
+    { ngx_null_string, 0 }
+};
+
+
+static ngx_conf_bitmask_t  ngx_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_null_string, 0 }
+};
+
+
+static ngx_str_t  ngx_smtp_auth_methods_names[] = {
+    ngx_string("PLAIN"), 
+    ngx_string("LOGIN"),
+    ngx_null_string,  /* APOP */
+    ngx_string("CRAM-MD5")
+};
+
+
+static ngx_str_t  ngx_pop3_auth_plain_capability =
+    ngx_string("+OK methods supported:" CRLF
+               "LOGIN" CRLF
+               "PLAIN" CRLF
+               "." CRLF);
+
+
+static ngx_str_t  ngx_pop3_auth_cram_md5_capability =
+    ngx_string("+OK methods supported:" CRLF
+               "LOGIN" CRLF
+               "PLAIN" CRLF
+               "CRAM-MD5" CRLF
+               "." CRLF);
+
+
+
+static ngx_command_t  ngx_mail_core_commands[] = {
+
+    { ngx_string("server"),
+      NGX_MAIL_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_NOARGS,
+      ngx_mail_core_server,
+      0,
+      0,
+      NULL },
+
+    { ngx_string("listen"),
+      NGX_MAIL_SRV_CONF|NGX_CONF_TAKE12,
+      ngx_mail_core_listen,
+      0,
+      0,
+      NULL },
+
+    { ngx_string("protocol"),
+      NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_enum_slot,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, protocol),
+      &ngx_mail_core_procotol },
+
+    { ngx_string("imap_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_core_srv_conf_t, imap_client_buffer_size),
+      NULL },
+
+    { ngx_string("so_keepalive"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, so_keepalive),
+      NULL },
+
+    { ngx_string("timeout"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_msec_slot,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, timeout),
+      NULL },
+
+    { ngx_string("pop3_capabilities"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
+      ngx_mail_core_capability,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, pop3_capabilities),
+      NULL },
+
+    { ngx_string("imap_capabilities"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
+      ngx_mail_core_capability,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, imap_capabilities),
+      NULL },
+
+    { ngx_string("smtp_capabilities"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
+      ngx_mail_core_capability,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, smtp_capabilities),
+      NULL },
+
+    { ngx_string("server_name"),
+      NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
+      ngx_conf_set_str_slot,
+      NGX_MAIL_SRV_CONF_OFFSET,
+      offsetof(ngx_mail_core_srv_conf_t, server_name),
+      NULL },
+
+    { ngx_string("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_core_srv_conf_t, pop3_auth_methods),
+      &ngx_pop3_auth_methods },
+
+    { ngx_string("pop3_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_core_srv_conf_t, pop3_auth_methods),
+      &ngx_pop3_auth_methods },
+
+    { 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_core_srv_conf_t, smtp_auth_methods),
+      &ngx_smtp_auth_methods },
+
+      ngx_null_command
+};
+
+
+static ngx_mail_module_t  ngx_mail_core_module_ctx = {
+    ngx_mail_core_create_main_conf,        /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    ngx_mail_core_create_srv_conf,         /* create server configuration */
+    ngx_mail_core_merge_srv_conf           /* merge server configuration */
+};
+
+
+ngx_module_t  ngx_mail_core_module = {
+    NGX_MODULE_V1,
+    &ngx_mail_core_module_ctx,             /* module context */
+    ngx_mail_core_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_core_create_main_conf(ngx_conf_t *cf)
+{
+    ngx_mail_core_main_conf_t  *cmcf;
+
+    cmcf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_core_main_conf_t));
+    if (cmcf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    if (ngx_array_init(&cmcf->servers, cf->pool, 4,
+                       sizeof(ngx_mail_core_srv_conf_t *))
+        != NGX_OK)
+    {
+        return NGX_CONF_ERROR;
+    }
+
+    if (ngx_array_init(&cmcf->listen, cf->pool, 4, sizeof(ngx_mail_listen_t))
+        != NGX_OK)
+    {
+        return NGX_CONF_ERROR;
+    }
+
+    return cmcf;
+}
+
+
+static void *
+ngx_mail_core_create_srv_conf(ngx_conf_t *cf)
+{
+    ngx_mail_core_srv_conf_t  *cscf;
+
+    cscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_core_srv_conf_t));
+    if (cscf == NULL) {
+        return NULL;
+    }
+
+    cscf->imap_client_buffer_size = NGX_CONF_UNSET_SIZE;
+    cscf->protocol = NGX_CONF_UNSET_UINT;
+    cscf->timeout = NGX_CONF_UNSET_MSEC;
+    cscf->so_keepalive = NGX_CONF_UNSET;
+
+    if (ngx_array_init(&cscf->pop3_capabilities, cf->pool, 4, sizeof(ngx_str_t))
+        != NGX_OK)
+    {
+        return NULL;
+    }
+
+    if (ngx_array_init(&cscf->imap_capabilities, cf->pool, 4, sizeof(ngx_str_t))
+        != NGX_OK)
+    {
+        return NULL;
+    }
+
+    if (ngx_array_init(&cscf->smtp_capabilities, cf->pool, 4, sizeof(ngx_str_t))
+        != NGX_OK)
+    {
+        return NULL;
+    }
+
+    return cscf;
+}
+
+
+static char *
+ngx_mail_core_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
+{
+    ngx_mail_core_srv_conf_t *prev = parent;
+    ngx_mail_core_srv_conf_t *conf = child;
+
+    u_char      *p;
+    size_t       size, stls_only_size;
+    ngx_str_t   *c, *d;
+    ngx_uint_t   i, m;
+
+    ngx_conf_merge_size_value(conf->imap_client_buffer_size,
+                              prev->imap_client_buffer_size,
+                              (size_t) ngx_pagesize);
+    ngx_conf_merge_msec_value(conf->timeout, prev->timeout, 60000);
+    ngx_conf_merge_uint_value(conf->protocol, prev->protocol,
+                              NGX_MAIL_IMAP_PROTOCOL);
+    ngx_conf_merge_value(conf->so_keepalive, prev->so_keepalive, 0);
+
+
+    ngx_conf_merge_bitmask_value(conf->pop3_auth_methods,
+                                 prev->pop3_auth_methods,
+                                 (NGX_CONF_BITMASK_SET
+                                  |NGX_MAIL_AUTH_PLAIN_ENABLED));
+
+    ngx_conf_merge_bitmask_value(conf->smtp_auth_methods,
+                                 prev->smtp_auth_methods,
+                                 (NGX_CONF_BITMASK_SET
+                                  |NGX_MAIL_AUTH_PLAIN_ENABLED
+                                  |NGX_MAIL_AUTH_LOGIN_ENABLED));
+
+
+    ngx_conf_merge_str_value(conf->server_name, prev->server_name, "");
+
+    if (conf->server_name.len == 0) {
+        conf->server_name.data = ngx_palloc(cf->pool, NGX_MAXHOSTNAMELEN);
+        if (conf->server_name.data == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        if (gethostname((char *) conf->server_name.data, NGX_MAXHOSTNAMELEN)
+            == -1)
+        {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, ngx_errno,
+                               "gethostname() failed");
+            return NGX_CONF_ERROR;
+        }
+
+        conf->server_name.len = ngx_strlen(conf->server_name.data);
+    }
+
+
+    if (conf->pop3_capabilities.nelts == 0) {
+        conf->pop3_capabilities = prev->pop3_capabilities;
+    }
+
+    if (conf->pop3_capabilities.nelts == 0) {
+
+        for (d = ngx_pop3_default_capabilities; d->len; d++) {
+            c = ngx_array_push(&conf->pop3_capabilities);
+            if (c == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            *c = *d;
+        }
+    }
+
+    size = sizeof("+OK Capability list follows" CRLF) - 1
+           + sizeof("." CRLF) - 1;
+
+    stls_only_size = size + sizeof("STLS" CRLF) - 1;
+
+    c = conf->pop3_capabilities.elts;
+    for (i = 0; i < conf->pop3_capabilities.nelts; i++) {
+        size += c[i].len + sizeof(CRLF) - 1;
+
+        if (ngx_strcasecmp(c[i].data, (u_char *) "USER") == 0) {
+            continue;
+        }
+
+        stls_only_size += c[i].len + sizeof(CRLF) - 1;
+    }
+
+    if (conf->pop3_auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED) {
+        size += sizeof("SASL LOGIN PLAIN CRAM-MD5" CRLF) - 1;
+
+    } else {
+        size += sizeof("SASL LOGIN PLAIN" CRLF) - 1;
+    }
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->pop3_capability.len = size;
+    conf->pop3_capability.data = p;
+
+    p = ngx_cpymem(p, "+OK Capability list follows" CRLF,
+                   sizeof("+OK Capability list follows" CRLF) - 1);
+
+    for (i = 0; i < conf->pop3_capabilities.nelts; i++) {
+        p = ngx_cpymem(p, c[i].data, c[i].len);
+        *p++ = CR; *p++ = LF;
+    }
+
+    if (conf->pop3_auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED) {
+        p = ngx_cpymem(p, "SASL LOGIN PLAIN CRAM-MD5" CRLF,
+                       sizeof("SASL LOGIN PLAIN CRAM-MD5" CRLF) - 1);
+
+    } else {
+        p = ngx_cpymem(p, "SASL LOGIN PLAIN" CRLF,
+                       sizeof("SASL LOGIN PLAIN" CRLF) - 1);
+    }
+
+    *p++ = '.'; *p++ = CR; *p = LF;
+
+
+    size += sizeof("STLS" CRLF) - 1;
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->pop3_starttls_capability.len = size;
+    conf->pop3_starttls_capability.data = p;
+
+    p = ngx_cpymem(p, conf->pop3_capability.data,
+                   conf->pop3_capability.len - (sizeof("." CRLF) - 1));
+
+    p = ngx_cpymem(p, "STLS" CRLF, sizeof("STLS" CRLF) - 1);
+    *p++ = '.'; *p++ = CR; *p = LF;
+
+
+    if (conf->pop3_auth_methods & NGX_MAIL_AUTH_CRAM_MD5_ENABLED) {
+        conf->pop3_auth_capability = ngx_pop3_auth_cram_md5_capability;
+
+    } else {
+        conf->pop3_auth_capability = ngx_pop3_auth_plain_capability;
+    }
+
+
+    p = ngx_palloc(cf->pool, stls_only_size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->pop3_starttls_only_capability.len = stls_only_size;
+    conf->pop3_starttls_only_capability.data = p;
+
+    p = ngx_cpymem(p, "+OK Capability list follows" CRLF,
+                   sizeof("+OK Capability list follows" CRLF) - 1);
+
+    for (i = 0; i < conf->pop3_capabilities.nelts; i++) {
+        if (ngx_strcasecmp(c[i].data, (u_char *) "USER") == 0) {
+            continue;
+        }
+
+        p = ngx_cpymem(p, c[i].data, c[i].len);
+        *p++ = CR; *p++ = LF;
+    }
+
+    p = ngx_cpymem(p, "STLS" CRLF, sizeof("STLS" CRLF) - 1);
+    *p++ = '.'; *p++ = CR; *p = LF;
+
+
+    if (conf->imap_capabilities.nelts == 0) {
+        conf->imap_capabilities = prev->imap_capabilities;
+    }
+
+    if (conf->imap_capabilities.nelts == 0) {
+
+        for (d = ngx_imap_default_capabilities; d->len; d++) {
+            c = ngx_array_push(&conf->imap_capabilities);
+            if (c == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            *c = *d;
+        }
+    }
+
+    size = sizeof("* CAPABILITY" CRLF) - 1;
+
+    c = conf->imap_capabilities.elts;
+    for (i = 0; i < conf->imap_capabilities.nelts; i++) {
+        size += 1 + c[i].len;
+    }
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->imap_capability.len = size;
+    conf->imap_capability.data = p;
+
+    p = ngx_cpymem(p, "* CAPABILITY", sizeof("* CAPABILITY") - 1);
+
+    for (i = 0; i < conf->imap_capabilities.nelts; i++) {
+        *p++ = ' ';
+        p = ngx_cpymem(p, c[i].data, c[i].len);
+    }
+
+    *p++ = CR; *p = LF;
+
+
+    size += sizeof(" STARTTLS") - 1;
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->imap_starttls_capability.len = size;
+    conf->imap_starttls_capability.data = p;
+
+    p = ngx_cpymem(p, conf->imap_capability.data,
+                   conf->imap_capability.len - (sizeof(CRLF) - 1));
+    p = ngx_cpymem(p, " STARTTLS", sizeof(" STARTTLS") - 1);
+    *p++ = CR; *p = LF;
+
+
+    size += sizeof(" LOGINDISABLED") - 1;
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->imap_starttls_only_capability.len = size;
+    conf->imap_starttls_only_capability.data = p;
+
+    p = ngx_cpymem(p, conf->imap_starttls_capability.data,
+                   conf->imap_starttls_capability.len - (sizeof(CRLF) - 1));
+    p = ngx_cpymem(p, " LOGINDISABLED", sizeof(" LOGINDISABLED") - 1);
+    *p++ = CR; *p = LF;
+
+
+    size = sizeof("220  ESMTP ready" CRLF) - 1 + conf->server_name.len;
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->smtp_greeting.len = size;
+    conf->smtp_greeting.data = p;
+
+    *p++ = '2'; *p++ = '2'; *p++ = '0'; *p++ = ' ';
+    p = ngx_cpymem(p, conf->server_name.data, conf->server_name.len);
+    ngx_memcpy(p, " ESMTP ready" CRLF, sizeof(" ESMTP ready" CRLF) - 1);
+
+
+    size = sizeof("250 " CRLF) - 1 + conf->server_name.len;
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->smtp_server_name.len = size;
+    conf->smtp_server_name.data = p;
+
+    *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' ';
+    p = ngx_cpymem(p, conf->server_name.data, conf->server_name.len);
+    *p++ = CR; *p = LF;
+
+
+    if (conf->smtp_capabilities.nelts == 0) {
+        conf->smtp_capabilities = prev->smtp_capabilities;
+    }
+
+    size = sizeof("250-") - 1 + conf->server_name.len + sizeof(CRLF) - 1
+           + sizeof("250 AUTH") - 1 + sizeof(CRLF) - 1;
+
+    c = conf->smtp_capabilities.elts;
+    for (i = 0; i < conf->smtp_capabilities.nelts; i++) {
+        size += sizeof("250 ") - 1 + c[i].len + sizeof(CRLF) - 1;
+    }
+
+    for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0;
+         m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED;
+         m <<= 1, i++)
+    {
+        if (m & conf->smtp_auth_methods) {
+            size += 1 + ngx_smtp_auth_methods_names[i].len;
+        }
+    }
+
+    p = ngx_palloc(cf->pool, size);
+    if (p == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->smtp_capability.len = size;
+    conf->smtp_capability.data = p;
+
+    *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
+    p = ngx_cpymem(p, conf->server_name.data, conf->server_name.len);
+    *p++ = CR; *p++ = LF;
+
+    for (i = 0; i < conf->smtp_capabilities.nelts; i++) {
+        *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
+        p = ngx_cpymem(p, c[i].data, c[i].len);
+        *p++ = CR; *p++ = LF;
+    }
+
+    *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_CRAM_MD5_ENABLED;
+         m <<= 1, i++)
+    {
+        if (m & conf->smtp_auth_methods) {
+            *p++ = ' ';
+            p = ngx_cpymem(p, ngx_smtp_auth_methods_names[i].data,
+                           ngx_smtp_auth_methods_names[i].len);
+        }
+    }
+
+    *p++ = CR; *p = LF;
+
+    return NGX_CONF_OK;
+}
+
+
+static char *
+ngx_mail_core_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    char                       *rv;
+    void                       *mconf;
+    ngx_uint_t                  m;
+    ngx_conf_t                  pcf;
+    ngx_mail_module_t          *module;
+    ngx_mail_conf_ctx_t        *ctx, *mail_ctx;
+    ngx_mail_core_srv_conf_t   *cscf, **cscfp;
+    ngx_mail_core_main_conf_t  *cmcf;
+
+
+    ctx = ngx_pcalloc(cf->pool, sizeof(ngx_mail_conf_ctx_t));
+    if (ctx == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    mail_ctx = cf->ctx;
+    ctx->main_conf = mail_ctx->main_conf;
+
+    /* the server{}'s srv_conf */
+
+    ctx->srv_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_mail_max_module);
+    if (ctx->srv_conf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    for (m = 0; ngx_modules[m]; m++) {
+        if (ngx_modules[m]->type != NGX_MAIL_MODULE) {
+            continue;
+        }
+
+        module = ngx_modules[m]->ctx;
+
+        if (module->create_srv_conf) {
+            mconf = module->create_srv_conf(cf);
+            if (mconf == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            ctx->srv_conf[ngx_modules[m]->ctx_index] = mconf;
+        }
+    }
+
+    /* the server configuration context */
+
+    cscf = ctx->srv_conf[ngx_mail_core_module.ctx_index];
+    cscf->ctx = ctx;
+
+    cmcf = ctx->main_conf[ngx_mail_core_module.ctx_index];
+
+    cscfp = ngx_array_push(&cmcf->servers);
+    if (cscfp == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    *cscfp = cscf;
+
+
+    /* parse inside server{} */
+
+    pcf = *cf;
+    cf->ctx = ctx;
+    cf->cmd_type = NGX_MAIL_SRV_CONF;
+
+    rv = ngx_conf_parse(cf, NULL);
+
+    *cf = pcf;
+
+    return rv;
+}
+
+
+/* AF_INET only */
+
+static char *
+ngx_mail_core_listen(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    ngx_str_t                  *value;
+    ngx_url_t                   u;
+    ngx_uint_t                  i;
+    ngx_mail_listen_t          *imls;
+    ngx_mail_core_main_conf_t  *cmcf;
+
+    value = cf->args->elts;
+
+    ngx_memzero(&u, sizeof(ngx_url_t));
+
+    u.url = value[1];
+    u.listen = 1;
+
+    if (ngx_parse_url(cf, &u) != NGX_OK) {
+        if (u.err) {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                               "%s in \"%V\" of the \"listen\" directive",
+                               u.err, &u.url);
+        }
+
+        return NGX_CONF_ERROR;
+    }
+
+    cmcf = ngx_mail_conf_get_module_main_conf(cf, ngx_mail_core_module);
+
+    imls = cmcf->listen.elts;
+
+    for (i = 0; i < cmcf->listen.nelts; i++) {
+
+        if (imls[i].addr != u.addr.in_addr || imls[i].port != u.port) {
+            continue;
+        }
+
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                           "duplicate \"%V\" address and port pair", &u.url);
+        return NGX_CONF_ERROR;
+    }
+
+    imls = ngx_array_push(&cmcf->listen);
+    if (imls == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    ngx_memzero(imls, sizeof(ngx_mail_listen_t));
+
+    imls->addr = u.addr.in_addr;
+    imls->port = u.port;
+    imls->family = AF_INET;
+    imls->ctx = cf->ctx;
+
+    if (cf->args->nelts == 2) {
+        return NGX_CONF_OK;
+    }
+
+    if (ngx_strcmp(value[2].data, "bind") == 0) {
+        imls->bind = 1;
+        return NGX_CONF_OK;
+    }
+
+    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                       "the invalid \"%V\" parameter", &value[2]);
+    return NGX_CONF_ERROR;
+}
+
+
+static char *
+ngx_mail_core_capability(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    char  *p = conf;
+
+    ngx_str_t    *c, *value;
+    ngx_uint_t    i;
+    ngx_array_t  *a;
+
+    a = (ngx_array_t *) (p + cmd->offset);
+
+    value = cf->args->elts;
+
+    for (i = 1; i < cf->args->nelts; i++) {
+        c = ngx_array_push(a);
+        if (c == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        *c = value[i];
+    }
+
+    return NGX_CONF_OK;
+}