nginx/src/http/ngx_http_header_filter_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_http.h>
  10 #include <nginx.h>
  11
  12
  13 static ngx_int_t ngx_http_header_filter_init(ngx_conf_t *cf);
  14 static ngx_int_t ngx_http_header_filter(ngx_http_request_t *r);
  15
  16
  17 static ngx_http_module_t  ngx_http_header_filter_module_ctx = {
  18     NULL,                                  /* preconfiguration */
  19     ngx_http_header_filter_init,           /* postconfiguration */
  20
  21     NULL,                                  /* create main configuration */
  22     NULL,                                  /* init main configuration */
  23
  24     NULL,                                  /* create server configuration */
  25     NULL,                                  /* merge server configuration */
  26
  27     NULL,                                  /* create location configuration */
  28     NULL,                                  /* merge location configuration */
  29 };
  30
  31
  32 ngx_module_t  ngx_http_header_filter_module = {
  33     NGX_MODULE_V1,
  34     &ngx_http_header_filter_module_ctx,    /* module context */
  35     NULL,                                  /* module directives */
  36     NGX_HTTP_MODULE,                       /* module type */
  37     NULL,                                  /* init master */
  38     NULL,                                  /* init module */
  39     NULL,                                  /* init process */
  40     NULL,                                  /* init thread */
  41     NULL,                                  /* exit thread */
  42     NULL,                                  /* exit process */
  43     NULL,                                  /* exit master */
  44     NGX_MODULE_V1_PADDING
  45 };
  46
  47
  48 static char ngx_http_server_string[] = "Server: nginx" CRLF;
  49 static char ngx_http_server_full_string[] = "Server: " NGINX_VER CRLF;
  50
  51
  52 static ngx_str_t ngx_http_status_lines[] = {
  53
  54     ngx_string("200 OK"),
  55     ngx_string("201 Created"),
  56     ngx_null_string,  /* "202 Accepted" */
  57     ngx_null_string,  /* "203 Non-Authoritative Information" */
  58     ngx_string("204 No Content"),
  59     ngx_null_string,  /* "205 Reset Content" */
  60     ngx_string("206 Partial Content"),
  61
  62     /* ngx_null_string, */  /* "207 Multi-Status" */
  63
  64 #define NGX_HTTP_LEVEL_200  7
  65
  66     /* ngx_null_string, */  /* "300 Multiple Choices" */
  67
  68     ngx_string("301 Moved Permanently"),
  69     ngx_string("302 Moved Temporarily"),
  70     ngx_null_string,  /* "303 See Other" */
  71     ngx_string("304 Not Modified"),
  72
  73     /* ngx_null_string, */  /* "305 Use Proxy" */
  74     /* ngx_null_string, */  /* "306 unused" */
  75     /* ngx_null_string, */  /* "307 Temporary Redirect" */
  76
  77 #define NGX_HTTP_LEVEL_300  4
  78
  79     ngx_string("400 Bad Request"),
  80     ngx_string("401 Unauthorized"),
  81     ngx_string("402 Payment Required"),
  82     ngx_string("403 Forbidden"),
  83     ngx_string("404 Not Found"),
  84     ngx_string("405 Not Allowed"),
  85     ngx_string("406 Not Acceptable"),
  86     ngx_null_string,  /* "407 Proxy Authentication Required" */
  87     ngx_string("408 Request Time-out"),
  88     ngx_string("409 Conflict"),
  89     ngx_string("410 Gone"),
  90     ngx_string("411 Length Required"),
  91     ngx_string("412 Precondition Failed"),
  92     ngx_string("413 Request Entity Too Large"),
  93     ngx_null_string,  /* "414 Request-URI Too Large", but we never send it
  94                        * because we treat such requests as the HTTP/0.9
  95                        * requests and send only a body without a header
  96                        */
  97     ngx_string("415 Unsupported Media Type"),
  98     ngx_string("416 Requested Range Not Satisfiable"),
  99
 100     /* ngx_null_string, */  /* "417 Expectation Failed" */
 101     /* ngx_null_string, */  /* "418 unused" */
 102     /* ngx_null_string, */  /* "419 unused" */
 103     /* ngx_null_string, */  /* "420 unused" */
 104     /* ngx_null_string, */  /* "421 unused" */
 105     /* ngx_null_string, */  /* "422 Unprocessable Entity" */
 106     /* ngx_null_string, */  /* "423 Locked" */
 107     /* ngx_null_string, */  /* "424 Failed Dependency" */
 108
 109 #define NGX_HTTP_LEVEL_400  17
 110
 111     ngx_string("500 Internal Server Error"),
 112     ngx_string("501 Method Not Implemented"),
 113     ngx_string("502 Bad Gateway"),
 114     ngx_string("503 Service Temporarily Unavailable"),
 115     ngx_string("504 Gateway Time-out"),
 116
 117     ngx_null_string,        /* "505 HTTP Version Not Supported" */
 118     ngx_null_string,        /* "506 Variant Also Negotiates" */
 119     ngx_string("507 Insufficient Storage"),
 120     /* ngx_null_string, */  /* "508 unused" */
 121     /* ngx_null_string, */  /* "509 unused" */
 122     /* ngx_null_string, */  /* "510 Not Extended" */
 123 };
 124
 125
 126 ngx_http_header_out_t  ngx_http_headers_out[] = {
 127     { ngx_string("Server"), offsetof(ngx_http_headers_out_t, server) },
 128     { ngx_string("Date"), offsetof(ngx_http_headers_out_t, date) },
 129 #if 0
 130     { ngx_string("Content-Type"),
 131                  offsetof(ngx_http_headers_out_t, content_type) },
 132 #endif
 133     { ngx_string("Content-Length"),
 134                  offsetof(ngx_http_headers_out_t, content_length) },
 135     { ngx_string("Content-Encoding"),
 136                  offsetof(ngx_http_headers_out_t, content_encoding) },
 137     { ngx_string("Location"), offsetof(ngx_http_headers_out_t, location) },
 138     { ngx_string("Last-Modified"),
 139                  offsetof(ngx_http_headers_out_t, last_modified) },
 140     { ngx_string("Accept-Ranges"),
 141                  offsetof(ngx_http_headers_out_t, accept_ranges) },
 142     { ngx_string("Expires"), offsetof(ngx_http_headers_out_t, expires) },
 143     { ngx_string("Cache-Control"),
 144                  offsetof(ngx_http_headers_out_t, cache_control) },
 145     { ngx_string("ETag"), offsetof(ngx_http_headers_out_t, etag) },
 146
 147     { ngx_null_string, 0 }
 148 };
 149
 150
 151 static ngx_int_t
 152 ngx_http_header_filter(ngx_http_request_t *r)
 153 {
 154     u_char                    *p;
 155     size_t                     len;
 156     ngx_str_t                  host;
 157     ngx_buf_t                 *b;
 158     ngx_uint_t                 status, i, port;
 159     ngx_chain_t                out;
 160     ngx_list_part_t           *part;
 161     ngx_table_elt_t           *header;
 162     ngx_http_core_loc_conf_t  *clcf;
 163     ngx_http_core_srv_conf_t  *cscf;
 164     struct sockaddr_in        *sin;
 165 #if (NGX_HAVE_INET6)
 166     struct sockaddr_in6       *sin6;
 167 #endif
 168     u_char                     addr[NGX_SOCKADDR_STRLEN];
 169
 170     r->header_sent = 1;
 171
 172     if (r != r->main) {
 173         return NGX_OK;
 174     }
 175
 176     if (r->http_version < NGX_HTTP_VERSION_10) {
 177         return NGX_OK;
 178     }
 179
 180     if (r->method == NGX_HTTP_HEAD) {
 181         r->header_only = 1;
 182     }
 183
 184     if (r->headers_out.last_modified_time != -1) {
 185         if (r->headers_out.status != NGX_HTTP_OK
 186             && r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT
 187             && r->headers_out.status != NGX_HTTP_NOT_MODIFIED)
 188         {
 189             r->headers_out.last_modified_time = -1;
 190             r->headers_out.last_modified = NULL;
 191         }
 192     }
 193
 194     len = sizeof("HTTP/1.x ") - 1 + sizeof(CRLF) - 1
 195           /* the end of the header */
 196           + sizeof(CRLF) - 1;
 197
 198     /* status line */
 199
 200     if (r->headers_out.status_line.len) {
 201         len += r->headers_out.status_line.len;
 202 #if (NGX_SUPPRESS_WARN)
 203         status = NGX_INVALID_ARRAY_INDEX;
 204 #endif
 205
 206     } else {
 207
 208         if (r->headers_out.status < NGX_HTTP_MOVED_PERMANENTLY) {
 209             /* 2XX */
 210             status = r->headers_out.status - NGX_HTTP_OK;
 211
 212             if (r->headers_out.status == NGX_HTTP_NO_CONTENT) {
 213                 r->header_only = 1;
 214                 r->headers_out.content_type.len = 0;
 215                 r->headers_out.content_type.data = NULL;
 216                 r->headers_out.last_modified_time = -1;
 217                 r->headers_out.last_modified = NULL;
 218                 r->headers_out.content_length = NULL;
 219                 r->headers_out.content_length_n = -1;
 220             }
 221
 222         } else if (r->headers_out.status < NGX_HTTP_BAD_REQUEST) {
 223             /* 3XX */
 224             status = r->headers_out.status - NGX_HTTP_MOVED_PERMANENTLY
 225                                            + NGX_HTTP_LEVEL_200;
 226
 227             if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED) {
 228                 r->header_only = 1;
 229             }
 230
 231         } else if (r->headers_out.status < NGX_HTTP_INTERNAL_SERVER_ERROR) {
 232             /* 4XX */
 233             status = r->headers_out.status - NGX_HTTP_BAD_REQUEST
 234                                            + NGX_HTTP_LEVEL_200
 235                                            + NGX_HTTP_LEVEL_300;
 236
 237         } else {
 238             /* 5XX */
 239             status = r->headers_out.status - NGX_HTTP_INTERNAL_SERVER_ERROR
 240                                            + NGX_HTTP_LEVEL_200
 241                                            + NGX_HTTP_LEVEL_300
 242                                            + NGX_HTTP_LEVEL_400;
 243         }
 244
 245         len += ngx_http_status_lines[status].len;
 246     }
 247
 248     clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
 249
 250     if (r->headers_out.server == NULL) {
 251         len += clcf->server_tokens ? sizeof(ngx_http_server_full_string) - 1:
 252                                      sizeof(ngx_http_server_string) - 1;
 253     }
 254
 255     if (r->headers_out.date == NULL) {
 256         len += sizeof("Date: Mon, 28 Sep 1970 06:00:00 GMT" CRLF) - 1;
 257     }
 258
 259     if (r->headers_out.content_type.len) {
 260         len += sizeof("Content-Type: ") - 1
 261                + r->headers_out.content_type.len + 2;
 262
 263         if (r->headers_out.content_type_len == r->headers_out.content_type.len
 264             && r->headers_out.charset.len)
 265         {
 266             len += sizeof("; charset=") - 1 + r->headers_out.charset.len;
 267         }
 268     }
 269
 270     if (r->headers_out.content_length == NULL
 271         && r->headers_out.content_length_n >= 0)
 272     {
 273         len += sizeof("Content-Length: ") - 1 + NGX_OFF_T_LEN + 2;
 274     }
 275
 276     if (r->headers_out.last_modified == NULL
 277         && r->headers_out.last_modified_time != -1)
 278     {
 279         len += sizeof("Last-Modified: Mon, 28 Sep 1970 06:00:00 GMT" CRLF) - 1;
 280     }
 281
 282     if (r->headers_out.location
 283         && r->headers_out.location->value.len
 284         && r->headers_out.location->value.data[0] == '/')
 285     {
 286         r->headers_out.location->hash = 0;
 287
 288         if (clcf->server_name_in_redirect) {
 289             cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
 290             host = cscf->server_name;
 291
 292         } else if (r->headers_in.server.len) {
 293             host = r->headers_in.server;
 294
 295         } else {
 296             host.len = NGX_SOCKADDR_STRLEN;
 297             host.data = addr;
 298
 299             if (ngx_http_server_addr(r, &host) != NGX_OK) {
 300                 return NGX_ERROR;
 301             }
 302         }
 303
 304         switch (r->connection->local_sockaddr->sa_family) {
 305
 306 #if (NGX_HAVE_INET6)
 307         case AF_INET6:
 308             sin6 = (struct sockaddr_in6 *) r->connection->local_sockaddr;
 309             port = ntohs(sin6->sin6_port);
 310             break;
 311 #endif
 312         default: /* AF_INET */
 313             sin = (struct sockaddr_in *) r->connection->local_sockaddr;
 314             port = ntohs(sin->sin_port);
 315             break;
 316         }
 317
 318         len += sizeof("Location: https://") - 1
 319                + host.len
 320                + r->headers_out.location->value.len + 2;
 321
 322         if (clcf->port_in_redirect) {
 323
 324 #if (NGX_HTTP_SSL)
 325             if (r->connection->ssl)
 326                 port = (port == 443) ? 0 : port;
 327             else
 328 #endif
 329                 port = (port == 80) ? 0 : port;
 330         }
 331
 332         if (port) {
 333             len += sizeof(":65535") - 1;
 334         }
 335
 336     } else {
 337         host.len = 0;
 338         host.data = NULL;
 339         port = 0;
 340     }
 341
 342     if (r->chunked) {
 343         len += sizeof("Transfer-Encoding: chunked" CRLF) - 1;
 344     }
 345
 346     if (r->keepalive) {
 347         len += sizeof("Connection: keep-alive" CRLF) - 1;
 348
 349         /*
 350          * MSIE and Opera ignore the "Keep-Alive: timeout=<N>" header.
 351          * MSIE keeps the connection alive for about 60-65 seconds.
 352          * Opera keeps the connection alive very long.
 353          * Mozilla keeps the connection alive for N plus about 1-10 seconds.
 354          * Konqueror keeps the connection alive for about N seconds.
 355          */
 356
 357         if (clcf->keepalive_header) {
 358             len += sizeof("Keep-Alive: timeout=") - 1 + NGX_TIME_T_LEN + 2;
 359         }
 360
 361     } else {
 362         len += sizeof("Connection: closed" CRLF) - 1;
 363     }
 364
 365 #if (NGX_HTTP_GZIP)
 366     if (r->gzip && clcf->gzip_vary) {
 367         len += sizeof("Vary: Accept-Encoding" CRLF) - 1;
 368     }
 369 #endif
 370
 371     part = &r->headers_out.headers.part;
 372     header = part->elts;
 373
 374     for (i = 0; /* void */; i++) {
 375
 376         if (i >= part->nelts) {
 377             if (part->next == NULL) {
 378                 break;
 379             }
 380
 381             part = part->next;
 382             header = part->elts;
 383             i = 0;
 384         }
 385
 386         if (header[i].hash == 0) {
 387             continue;
 388         }
 389
 390         len += header[i].key.len + sizeof(": ") - 1 + header[i].value.len
 391                + sizeof(CRLF) - 1;
 392     }
 393
 394     b = ngx_create_temp_buf(r->pool, len);
 395     if (b == NULL) {
 396         return NGX_ERROR;
 397     }
 398
 399     /* "HTTP/1.x " */
 400     b->last = ngx_cpymem(b->last, "HTTP/1.1 ", sizeof("HTTP/1.x ") - 1);
 401
 402     /* status line */
 403     if (r->headers_out.status_line.len) {
 404         b->last = ngx_copy(b->last, r->headers_out.status_line.data,
 405                            r->headers_out.status_line.len);
 406
 407     } else {
 408         b->last = ngx_copy(b->last, ngx_http_status_lines[status].data,
 409                            ngx_http_status_lines[status].len);
 410     }
 411     *b->last++ = CR; *b->last++ = LF;
 412
 413     if (r->headers_out.server == NULL) {
 414         if (clcf->server_tokens) {
 415             p = (u_char *) ngx_http_server_full_string;
 416             len = sizeof(ngx_http_server_full_string) - 1;
 417
 418         } else {
 419             p = (u_char *) ngx_http_server_string;
 420             len = sizeof(ngx_http_server_string) - 1;
 421         }
 422
 423         b->last = ngx_cpymem(b->last, p, len);
 424     }
 425
 426     if (r->headers_out.date == NULL) {
 427         b->last = ngx_cpymem(b->last, "Date: ", sizeof("Date: ") - 1);
 428         b->last = ngx_cpymem(b->last, ngx_cached_http_time.data,
 429                              ngx_cached_http_time.len);
 430
 431         *b->last++ = CR; *b->last++ = LF;
 432     }
 433
 434     if (r->headers_out.content_type.len) {
 435         b->last = ngx_cpymem(b->last, "Content-Type: ",
 436                              sizeof("Content-Type: ") - 1);
 437         p = b->last;
 438         b->last = ngx_copy(b->last, r->headers_out.content_type.data,
 439                            r->headers_out.content_type.len);
 440
 441         if (r->headers_out.content_type_len == r->headers_out.content_type.len
 442             && r->headers_out.charset.len)
 443         {
 444             b->last = ngx_cpymem(b->last, "; charset=",
 445                                  sizeof("; charset=") - 1);
 446             b->last = ngx_copy(b->last, r->headers_out.charset.data,
 447                                r->headers_out.charset.len);
 448
 449             /* update r->headers_out.content_type for possible logging */
 450
 451             r->headers_out.content_type.len = b->last - p;
 452             r->headers_out.content_type.data = p;
 453         }
 454
 455         *b->last++ = CR; *b->last++ = LF;
 456     }
 457
 458     if (r->headers_out.content_length == NULL
 459         && r->headers_out.content_length_n >= 0)
 460     {
 461         b->last = ngx_sprintf(b->last, "Content-Length: %O" CRLF,
 462                               r->headers_out.content_length_n);
 463     }
 464
 465     if (r->headers_out.last_modified == NULL
 466         && r->headers_out.last_modified_time != -1)
 467     {
 468         b->last = ngx_cpymem(b->last, "Last-Modified: ",
 469                              sizeof("Last-Modified: ") - 1);
 470         b->last = ngx_http_time(b->last, r->headers_out.last_modified_time);
 471
 472         *b->last++ = CR; *b->last++ = LF;
 473     }
 474
 475     if (host.data) {
 476
 477         p = b->last + sizeof("Location: ") - 1;
 478
 479         b->last = ngx_cpymem(b->last, "Location: http",
 480                              sizeof("Location: http") - 1);
 481
 482 #if (NGX_HTTP_SSL)
 483         if (r->connection->ssl) {
 484             *b->last++ ='s';
 485         }
 486 #endif
 487
 488         *b->last++ = ':'; *b->last++ = '/'; *b->last++ = '/';
 489         b->last = ngx_copy(b->last, host.data, host.len);
 490
 491         if (port) {
 492             b->last = ngx_sprintf(b->last, ":%ui", port);
 493         }
 494
 495         b->last = ngx_copy(b->last, r->headers_out.location->value.data,
 496                            r->headers_out.location->value.len);
 497
 498         /* update r->headers_out.location->value for possible logging */
 499
 500         r->headers_out.location->value.len = b->last - p;
 501         r->headers_out.location->value.data = p;
 502         r->headers_out.location->key.len = sizeof("Location: ") - 1;
 503         r->headers_out.location->key.data = (u_char *) "Location: ";
 504
 505         *b->last++ = CR; *b->last++ = LF;
 506     }
 507
 508     if (r->chunked) {
 509         b->last = ngx_cpymem(b->last, "Transfer-Encoding: chunked" CRLF,
 510                              sizeof("Transfer-Encoding: chunked" CRLF) - 1);
 511     }
 512
 513     if (r->keepalive) {
 514         b->last = ngx_cpymem(b->last, "Connection: keep-alive" CRLF,
 515                              sizeof("Connection: keep-alive" CRLF) - 1);
 516
 517         if (clcf->keepalive_header) {
 518             b->last = ngx_sprintf(b->last, "Keep-Alive: timeout=%T" CRLF,
 519                                   clcf->keepalive_header);
 520         }
 521
 522     } else {
 523         b->last = ngx_cpymem(b->last, "Connection: close" CRLF,
 524                              sizeof("Connection: close" CRLF) - 1);
 525     }
 526
 527 #if (NGX_HTTP_GZIP)
 528     if (r->gzip && clcf->gzip_vary) {
 529         b->last = ngx_cpymem(b->last, "Vary: Accept-Encoding" CRLF,
 530                              sizeof("Vary: Accept-Encoding" CRLF) - 1);
 531     }
 532 #endif
 533
 534     part = &r->headers_out.headers.part;
 535     header = part->elts;
 536
 537     for (i = 0; /* void */; i++) {
 538
 539         if (i >= part->nelts) {
 540             if (part->next == NULL) {
 541                 break;
 542             }
 543
 544             part = part->next;
 545             header = part->elts;
 546             i = 0;
 547         }
 548
 549         if (header[i].hash == 0) {
 550             continue;
 551         }
 552
 553         b->last = ngx_copy(b->last, header[i].key.data, header[i].key.len);
 554         *b->last++ = ':'; *b->last++ = ' ';
 555
 556         b->last = ngx_copy(b->last, header[i].value.data, header[i].value.len);
 557         *b->last++ = CR; *b->last++ = LF;
 558     }
 559
 560     ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
 561                    "%*s\n", (size_t) (b->last - b->pos), b->pos);
 562
 563     /* the end of HTTP header */
 564     *b->last++ = CR; *b->last++ = LF;
 565
 566     r->header_size = b->last - b->pos;
 567
 568     if (r->header_only) {
 569         b->last_buf = 1;
 570     }
 571
 572     out.buf = b;
 573     out.next = NULL;
 574
 575     return ngx_http_write_filter(r, &out);
 576 }
 577
 578
 579 static ngx_int_t
 580 ngx_http_header_filter_init(ngx_conf_t *cf)
 581 {
 582     ngx_http_top_header_filter = ngx_http_header_filter;
 583
 584     return NGX_OK;
 585 }