nginx/src/mail/ngx_mail_smtp_module.c

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  */
   5
   6
   7 #include <ngx_config.h>
   8 #include <ngx_core.h>
   9 #include <ngx_event.h>
  10 #include <ngx_mail.h>
  11 #include <ngx_mail_smtp_module.h>
  12
  13
  14 static void *ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf);
  15 static char *ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent,
  16     void *child);
  17
  18
  19 static ngx_conf_bitmask_t  ngx_mail_smtp_auth_methods[] = {
  20     { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED },
  21     { ngx_string("login"), NGX_MAIL_AUTH_LOGIN_ENABLED },
  22     { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED },
  23     { ngx_string("none"), NGX_MAIL_AUTH_NONE_ENABLED },
  24     { ngx_null_string, 0 }
  25 };
  26
  27
  28 static ngx_str_t  ngx_mail_smtp_auth_methods_names[] = {
  29     ngx_string("PLAIN"),
  30     ngx_string("LOGIN"),
  31     ngx_null_string,  /* APOP */
  32     ngx_string("CRAM-MD5"),
  33     ngx_null_string   /* NONE */
  34 };
  35
  36
  37 static ngx_mail_protocol_t  ngx_mail_smtp_protocol = {
  38     ngx_string("smtp"),
  39     { 25, 465, 587, 0 },
  40     NGX_MAIL_SMTP_PROTOCOL,
  41
  42     ngx_mail_smtp_init_session,
  43     ngx_mail_smtp_init_protocol,
  44     ngx_mail_smtp_parse_command,
  45     ngx_mail_smtp_auth_state,
  46
  47     ngx_string("451 4.3.2 Internal server error" CRLF)
  48 };
  49
  50
  51 static ngx_command_t  ngx_mail_smtp_commands[] = {
  52
  53     { ngx_string("smtp_client_buffer"),
  54       NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
  55       ngx_conf_set_size_slot,
  56       NGX_MAIL_SRV_CONF_OFFSET,
  57       offsetof(ngx_mail_smtp_srv_conf_t, client_buffer_size),
  58       NULL },
  59
  60     { ngx_string("smtp_greeting_delay"),
  61       NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
  62       ngx_conf_set_msec_slot,
  63       NGX_MAIL_SRV_CONF_OFFSET,
  64       offsetof(ngx_mail_smtp_srv_conf_t, greeting_delay),
  65       NULL },
  66
  67     { ngx_string("smtp_capabilities"),
  68       NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
  69       ngx_mail_capabilities,
  70       NGX_MAIL_SRV_CONF_OFFSET,
  71       offsetof(ngx_mail_smtp_srv_conf_t, capabilities),
  72       NULL },
  73
  74     { ngx_string("smtp_auth"),
  75       NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
  76       ngx_conf_set_bitmask_slot,
  77       NGX_MAIL_SRV_CONF_OFFSET,
  78       offsetof(ngx_mail_smtp_srv_conf_t, auth_methods),
  79       &ngx_mail_smtp_auth_methods },
  80
  81       ngx_null_command
  82 };
  83
  84
  85 static ngx_mail_module_t  ngx_mail_smtp_module_ctx = {
  86     &ngx_mail_smtp_protocol,               /* protocol */
  87
  88     NULL,                                  /* create main configuration */
  89     NULL,                                  /* init main configuration */
  90
  91     ngx_mail_smtp_create_srv_conf,         /* create server configuration */
  92     ngx_mail_smtp_merge_srv_conf           /* merge server configuration */
  93 };
  94
  95
  96 ngx_module_t  ngx_mail_smtp_module = {
  97     NGX_MODULE_V1,
  98     &ngx_mail_smtp_module_ctx,             /* module context */
  99     ngx_mail_smtp_commands,                /* module directives */
 100     NGX_MAIL_MODULE,                       /* module type */
 101     NULL,                                  /* init master */
 102     NULL,                                  /* init module */
 103     NULL,                                  /* init process */
 104     NULL,                                  /* init thread */
 105     NULL,                                  /* exit thread */
 106     NULL,                                  /* exit process */
 107     NULL,                                  /* exit master */
 108     NGX_MODULE_V1_PADDING
 109 };
 110
 111
 112 static void *
 113 ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf)
 114 {
 115     ngx_mail_smtp_srv_conf_t  *sscf;
 116
 117     sscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_smtp_srv_conf_t));
 118     if (sscf == NULL) {
 119         return NULL;
 120     }
 121
 122     sscf->client_buffer_size = NGX_CONF_UNSET_SIZE;
 123     sscf->greeting_delay = NGX_CONF_UNSET_MSEC;
 124
 125     if (ngx_array_init(&sscf->capabilities, cf->pool, 4, sizeof(ngx_str_t))
 126         != NGX_OK)
 127     {
 128         return NULL;
 129     }
 130
 131     return sscf;
 132 }
 133
 134
 135 static char *
 136 ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
 137 {
 138     ngx_mail_smtp_srv_conf_t *prev = parent;
 139     ngx_mail_smtp_srv_conf_t *conf = child;
 140
 141     u_char                    *p, *auth, *last;
 142     size_t                     size;
 143     ngx_str_t                 *c;
 144     ngx_uint_t                 i, m, auth_enabled;
 145     ngx_mail_core_srv_conf_t  *cscf;
 146
 147     ngx_conf_merge_size_value(conf->client_buffer_size,
 148                               prev->client_buffer_size,
 149                               (size_t) ngx_pagesize);
 150
 151     ngx_conf_merge_msec_value(conf->greeting_delay,
 152                               prev->greeting_delay, 0);
 153
 154     ngx_conf_merge_bitmask_value(conf->auth_methods,
 155                               prev->auth_methods,
 156                               (NGX_CONF_BITMASK_SET
 157                                |NGX_MAIL_AUTH_PLAIN_ENABLED
 158                                |NGX_MAIL_AUTH_LOGIN_ENABLED));
 159
 160
 161     cscf = ngx_mail_conf_get_module_srv_conf(cf, ngx_mail_core_module);
 162
 163     size = sizeof("220  ESMTP ready" CRLF) - 1 + cscf->server_name.len;
 164
 165     p = ngx_pnalloc(cf->pool, size);
 166     if (p == NULL) {
 167         return NGX_CONF_ERROR;
 168     }
 169
 170     conf->greeting.len = size;
 171     conf->greeting.data = p;
 172
 173     *p++ = '2'; *p++ = '2'; *p++ = '0'; *p++ = ' ';
 174     p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
 175     ngx_memcpy(p, " ESMTP ready" CRLF, sizeof(" ESMTP ready" CRLF) - 1);
 176
 177
 178     size = sizeof("250 " CRLF) - 1 + cscf->server_name.len;
 179
 180     p = ngx_pnalloc(cf->pool, size);
 181     if (p == NULL) {
 182         return NGX_CONF_ERROR;
 183     }
 184
 185     conf->server_name.len = size;
 186     conf->server_name.data = p;
 187
 188     *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' ';
 189     p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
 190     *p++ = CR; *p = LF;
 191
 192
 193     if (conf->capabilities.nelts == 0) {
 194         conf->capabilities = prev->capabilities;
 195     }
 196
 197     size = sizeof("250-") - 1 + cscf->server_name.len + sizeof(CRLF) - 1;
 198
 199     c = conf->capabilities.elts;
 200     for (i = 0; i < conf->capabilities.nelts; i++) {
 201         size += sizeof("250 ") - 1 + c[i].len + sizeof(CRLF) - 1;
 202     }
 203
 204     auth_enabled = 0;
 205
 206     for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0;
 207          m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED;
 208          m <<= 1, i++)
 209     {
 210         if (m & conf->auth_methods) {
 211             size += 1 + ngx_mail_smtp_auth_methods_names[i].len;
 212             auth_enabled = 1;
 213         }
 214     }
 215
 216     if (auth_enabled) {
 217         size += sizeof("250 AUTH") - 1 + sizeof(CRLF) - 1;
 218     }
 219
 220     p = ngx_pnalloc(cf->pool, size);
 221     if (p == NULL) {
 222         return NGX_CONF_ERROR;
 223     }
 224
 225     conf->capability.len = size;
 226     conf->capability.data = p;
 227
 228     last = p;
 229
 230     *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
 231     p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
 232     *p++ = CR; *p++ = LF;
 233
 234     for (i = 0; i < conf->capabilities.nelts; i++) {
 235         last = p;
 236         *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
 237         p = ngx_cpymem(p, c[i].data, c[i].len);
 238         *p++ = CR; *p++ = LF;
 239     }
 240
 241     auth = p;
 242
 243     if (auth_enabled) {
 244         last = p;
 245
 246         *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' ';
 247         *p++ = 'A'; *p++ = 'U'; *p++ = 'T'; *p++ = 'H';
 248
 249         for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0;
 250              m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED;
 251              m <<= 1, i++)
 252         {
 253             if (m & conf->auth_methods) {
 254                 *p++ = ' ';
 255                 p = ngx_cpymem(p, ngx_mail_smtp_auth_methods_names[i].data,
 256                                ngx_mail_smtp_auth_methods_names[i].len);
 257             }
 258         }
 259
 260         *p++ = CR; *p = LF;
 261
 262     } else {
 263         last[3] = ' ';
 264     }
 265
 266     size += sizeof("250 STARTTLS" CRLF) - 1;
 267
 268     p = ngx_pnalloc(cf->pool, size);
 269     if (p == NULL) {
 270         return NGX_CONF_ERROR;
 271     }
 272
 273     conf->starttls_capability.len = size;
 274     conf->starttls_capability.data = p;
 275
 276     p = ngx_cpymem(p, conf->capability.data, conf->capability.len);
 277
 278     p = ngx_cpymem(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1);
 279     *p++ = CR; *p = LF;
 280
 281     p = conf->starttls_capability.data
 282         + (last - conf->capability.data) + 3;
 283     *p = '-';
 284
 285     size = (auth - conf->capability.data)
 286             + sizeof("250 STARTTLS" CRLF) - 1;
 287
 288     p = ngx_pnalloc(cf->pool, size);
 289     if (p == NULL) {
 290         return NGX_CONF_ERROR;
 291     }
 292
 293     conf->starttls_only_capability.len = size;
 294     conf->starttls_only_capability.data = p;
 295
 296     p = ngx_cpymem(p, conf->capability.data, auth - conf->capability.data);
 297
 298     ngx_memcpy(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1);
 299
 300     if (last < auth) {
 301         p = conf->starttls_only_capability.data
 302             + (last - conf->capability.data) + 3;
 303         *p = '-';
 304     }
 305
 306     return NGX_CONF_OK;
 307 }