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/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#include <nginx.h>
static ngx_int_t ngx_http_header_filter_init(ngx_cycle_t *cycle);
static ngx_int_t ngx_http_header_filter(ngx_http_request_t *r);
static ngx_http_module_t ngx_http_header_filter_module_ctx = {
NULL, /* pre conf */
NULL, /* create main configuration */
NULL, /* init main configuration */
NULL, /* create server configuration */
NULL, /* merge server configuration */
NULL, /* create location configuration */
NULL, /* merge location configuration */
};
ngx_module_t ngx_http_header_filter_module = {
NGX_MODULE,
&ngx_http_header_filter_module_ctx, /* module context */
NULL, /* module directives */
NGX_HTTP_MODULE, /* module type */
ngx_http_header_filter_init, /* init module */
NULL /* init child */
};
static char server_string[] = "Server: " NGINX_VER CRLF;
static ngx_str_t http_codes[] = {
ngx_string("200 OK"),
ngx_null_string, /* "201 Created" */
ngx_null_string, /* "202 Accepted" */
ngx_null_string, /* "203 Non-Authoritative Information" */
ngx_null_string, /* "204 No Content" */
ngx_null_string, /* "205 Reset Content" */
ngx_string("206 Partial Content"),
ngx_null_string, /* "207 Multi-Status" */
#if 0
ngx_null_string, /* "300 Multiple Choices" */
#endif
ngx_string("301 Moved Permanently"),
#if 0
ngx_string("302 Moved Temporarily"),
#else
ngx_string("302 Found"),
#endif
ngx_null_string, /* "303 See Other" */
ngx_string("304 Not Modified"),
ngx_string("400 Bad Request"),
ngx_string("401 Unauthorized"),
ngx_null_string, /* "402 Payment Required" */
ngx_string("403 Forbidden"),
ngx_string("404 Not Found"),
ngx_string("405 Not Allowed"),
ngx_null_string, /* "406 Not Acceptable" */
ngx_null_string, /* "407 Proxy Authentication Required" */
ngx_string("408 Request Time-out"),
ngx_null_string, /* "409 Conflict" */
ngx_null_string, /* "410 Gone" */
ngx_string("411 Length Required"),
ngx_null_string, /* "412 Precondition Failed" */
ngx_string("413 Request Entity Too Large"),
ngx_null_string, /* "414 Request-URI Too Large" but we never send it
* because we treat such requests as the HTTP/0.9
* requests and send only a body without a header
*/
ngx_null_string, /* "415 Unsupported Media Type" */
ngx_string("416 Requested Range Not Satisfiable"),
ngx_string("500 Internal Server Error"),
ngx_string("501 Method Not Implemented"),
ngx_string("502 Bad Gateway"),
ngx_string("503 Service Temporarily Unavailable"),
ngx_string("504 Gateway Time-out")
};
ngx_http_header_t ngx_http_headers_out[] = {
{ ngx_string("Server"), offsetof(ngx_http_headers_out_t, server) },
{ ngx_string("Date"), offsetof(ngx_http_headers_out_t, date) },
{ ngx_string("Content-Type"),
offsetof(ngx_http_headers_out_t, content_type) },
{ ngx_string("Content-Length"),
offsetof(ngx_http_headers_out_t, content_length) },
{ ngx_string("Content-Encoding"),
offsetof(ngx_http_headers_out_t, content_encoding) },
{ ngx_string("Location"), offsetof(ngx_http_headers_out_t, location) },
{ ngx_string("Last-Modified"),
offsetof(ngx_http_headers_out_t, last_modified) },
{ ngx_string("Accept-Ranges"),
offsetof(ngx_http_headers_out_t, accept_ranges) },
{ ngx_string("Expires"), offsetof(ngx_http_headers_out_t, expires) },
{ ngx_string("Cache-Control"),
offsetof(ngx_http_headers_out_t, cache_control) },
{ ngx_string("ETag"), offsetof(ngx_http_headers_out_t, etag) },
{ ngx_null_string, 0 }
};
static ngx_int_t ngx_http_header_filter(ngx_http_request_t *r)
{
u_char *p;
size_t len;
ngx_uint_t status, i;
ngx_buf_t *b;
ngx_chain_t *ln;
ngx_list_part_t *part;
ngx_table_elt_t *header;
ngx_http_core_loc_conf_t *clcf;
if (r->http_version < NGX_HTTP_VERSION_10) {
return NGX_OK;
}
if (r->method == NGX_HTTP_HEAD) {
r->header_only = 1;
}
if (r->headers_out.last_modified_time != -1) {
if (r->headers_out.status != NGX_HTTP_OK
&& r->headers_out.status != NGX_HTTP_NOT_MODIFIED
&& r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT)
{
r->headers_out.last_modified_time = -1;
r->headers_out.last_modified = NULL;
}
}
/* 2 is for trailing "\r\n" and 2 is for "\r\n" in the end of header */
len = sizeof("HTTP/1.x ") - 1 + 2 + 2;
/* status line */
if (r->headers_out.status_line.len) {
len += r->headers_out.status_line.len;
#if (NGX_SUPPRESS_WARN)
status = NGX_INVALID_ARRAY_INDEX;
#endif
} else {
if (r->headers_out.status < NGX_HTTP_MOVED_PERMANENTLY) {
/* 2XX */
status = r->headers_out.status - NGX_HTTP_OK;
} else if (r->headers_out.status < NGX_HTTP_BAD_REQUEST) {
/* 3XX */
status = r->headers_out.status - NGX_HTTP_MOVED_PERMANENTLY + 8;
if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED) {
r->header_only = 1;
}
} else if (r->headers_out.status < NGX_HTTP_INTERNAL_SERVER_ERROR) {
/* 4XX */
status = r->headers_out.status - NGX_HTTP_BAD_REQUEST + 8 + 4;
} else {
/* 5XX */
status = r->headers_out.status
- NGX_HTTP_INTERNAL_SERVER_ERROR + 8 + 4 + 17;
}
len += http_codes[status].len;
}
if (r->headers_out.server && r->headers_out.server->key.len) {
len += r->headers_out.server->key.len
+ r->headers_out.server->value.len + 2;
} else {
len += sizeof(server_string) - 1;
}
if (r->headers_out.date && r->headers_out.date->key.len) {
len += r->headers_out.date->key.len
+ r->headers_out.date->value.len + 2;
} else {
len += sizeof("Date: Mon, 28 Sep 1970 06:00:00 GMT" CRLF) - 1;
}
if (r->headers_out.content_length == NULL) {
if (r->headers_out.content_length_n >= 0) {
len += sizeof("Content-Length: ") - 1 + NGX_OFF_T_LEN + 2;
}
}
if (r->headers_out.content_type && r->headers_out.content_type->value.len) {
r->headers_out.content_type->key.len = 0;
len += sizeof("Content-Type: ") - 1
+ r->headers_out.content_type->value.len + 2;
if (r->headers_out.charset.len) {
len += sizeof("; charset=") - 1 + r->headers_out.charset.len;
}
}
if (r->headers_out.location
&& r->headers_out.location->value.len
&& r->headers_out.location->value.data[0] == '/')
{
r->headers_out.location->key.len = 0;
len += sizeof("Location: http://") - 1
+ r->server_name.len + r->headers_out.location->value.len + 2;
if (r->port != 80) {
len += r->port_text->len;
}
}
if (r->headers_out.last_modified && r->headers_out.last_modified->key.len) {
len += r->headers_out.last_modified->key.len
+ r->headers_out.last_modified->value.len + 2;
} else if (r->headers_out.last_modified_time != -1) {
len += sizeof("Last-Modified: Mon, 28 Sep 1970 06:00:00 GMT" CRLF) - 1;
}
if (r->chunked) {
len += sizeof("Transfer-Encoding: chunked" CRLF) - 1;
}
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
if (r->keepalive) {
len += sizeof("Connection: keep-alive" CRLF) - 1;
/*
* MSIE and Opera ignore the "Keep-Alive: timeout=<N>" header.
* MSIE keeps the connection alive for about 60-65 seconds.
* Opera keeps the connection alive very long.
* Mozilla keeps the connection alive for N plus about 1-10 seconds.
* Konqueror keeps the connection alive for about N seconds.
*/
if (clcf->keepalive_header) {
len += sizeof("Keep-Alive: timeout=") - 1 + TIME_T_LEN + 2;
}
} else {
len += sizeof("Connection: closed" CRLF) - 1;
}
part = &r->headers_out.headers.part;
header = part->elts;
for (i = 0; /* void */; i++) {
if (i >= part->nelts) {
if (part->next == NULL) {
break;
}
part = part->next;
header = part->elts;
i = 0;
}
if (header[i].key.len == 0) {
continue;
}
/* 2 is for ": " and 2 is for "\r\n" */
len += header[i].key.len + 2 + header[i].value.len + 2;
}
if (!(b = ngx_create_temp_buf(r->pool, len))) {
return NGX_ERROR;
}
/* "HTTP/1.x " */
b->last = ngx_cpymem(b->last, "HTTP/1.1 ", sizeof("HTTP/1.x ") - 1);
/* status line */
if (r->headers_out.status_line.len) {
b->last = ngx_cpymem(b->last, r->headers_out.status_line.data,
r->headers_out.status_line.len);
} else {
b->last = ngx_cpymem(b->last, http_codes[status].data,
http_codes[status].len);
}
*(b->last++) = CR; *(b->last++) = LF;
if (!(r->headers_out.server && r->headers_out.server->key.len)) {
b->last = ngx_cpymem(b->last, server_string, sizeof(server_string) - 1);
}
if (!(r->headers_out.date && r->headers_out.date->key.len)) {
b->last = ngx_cpymem(b->last, "Date: ", sizeof("Date: ") - 1);
b->last = ngx_cpymem(b->last, ngx_cached_http_time.data,
ngx_cached_http_time.len);
*(b->last++) = CR; *(b->last++) = LF;
}
if (r->headers_out.content_length == NULL) {
if (r->headers_out.content_length_n >= 0) {
b->last = ngx_sprintf(b->last, "Content-Length: %O" CRLF,
r->headers_out.content_length_n);
}
}
if (r->headers_out.content_type && r->headers_out.content_type->value.len) {
b->last = ngx_cpymem(b->last, "Content-Type: ",
sizeof("Content-Type: ") - 1);
p = b->last;
b->last = ngx_cpymem(b->last, r->headers_out.content_type->value.data,
r->headers_out.content_type->value.len);
if (r->headers_out.charset.len) {
b->last = ngx_cpymem(b->last, "; charset=",
sizeof("; charset=") - 1);
b->last = ngx_cpymem(b->last, r->headers_out.charset.data,
r->headers_out.charset.len);
r->headers_out.content_type->value.len = b->last - p;
r->headers_out.content_type->value.data = p;
}
*(b->last++) = CR; *(b->last++) = LF;
}
if (r->headers_out.location
&& r->headers_out.location->value.len
&& r->headers_out.location->value.data[0] == '/')
{
p = b->last + sizeof("Location: ") - 1;
b->last = ngx_cpymem(b->last, "Location: http://",
sizeof("Location: http://") - 1);
b->last = ngx_cpymem(b->last, r->server_name.data,
r->server_name.len);
if (r->port != 80) {
b->last = ngx_cpymem(b->last, r->port_text->data,
r->port_text->len);
}
b->last = ngx_cpymem(b->last, r->headers_out.location->value.data,
r->headers_out.location->value.len);
r->headers_out.location->value.len = b->last - p;
r->headers_out.location->value.data = p;
*(b->last++) = CR; *(b->last++) = LF;
}
if (!(r->headers_out.last_modified && r->headers_out.last_modified->key.len)
&& r->headers_out.last_modified_time != -1)
{
b->last = ngx_cpymem(b->last, "Last-Modified: ",
sizeof("Last-Modified: ") - 1);
b->last = ngx_http_time(b->last, r->headers_out.last_modified_time);
*(b->last++) = CR; *(b->last++) = LF;
}
if (r->chunked) {
b->last = ngx_cpymem(b->last, "Transfer-Encoding: chunked" CRLF,
sizeof("Transfer-Encoding: chunked" CRLF) - 1);
}
if (r->keepalive) {
b->last = ngx_cpymem(b->last, "Connection: keep-alive" CRLF,
sizeof("Connection: keep-alive" CRLF) - 1);
if (clcf->keepalive_header) {
b->last = ngx_sprintf(b->last, "Keep-Alive: timeout=%T" CRLF,
clcf->keepalive_header);
}
} else {
b->last = ngx_cpymem(b->last, "Connection: close" CRLF,
sizeof("Connection: close" CRLF) - 1);
}
part = &r->headers_out.headers.part;
header = part->elts;
for (i = 0; /* void */; i++) {
if (i >= part->nelts) {
if (part->next == NULL) {
break;
}
part = part->next;
header = part->elts;
i = 0;
}
if (header[i].key.len == 0) {
continue;
}
b->last = ngx_cpymem(b->last, header[i].key.data, header[i].key.len);
*(b->last++) = ':' ; *(b->last++) = ' ' ;
b->last = ngx_cpymem(b->last, header[i].value.data,
header[i].value.len);
*(b->last++) = CR; *(b->last++) = LF;
}
#if (NGX_DEBUG)
*(b->last) = '\0';
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "%s\n", b->pos);
#endif
/* the end of HTTP header */
*(b->last++) = CR; *(b->last++) = LF;
r->header_size = b->last - b->pos;
if (r->header_only) {
b->last_buf = 1;
}
if (!(ln = ngx_alloc_chain_link(r->pool))) {
return NGX_ERROR;
}
ln->buf = b;
ln->next = NULL;
return ngx_http_write_filter(r, ln);
}
static ngx_int_t ngx_http_header_filter_init(ngx_cycle_t *cycle)
{
ngx_http_top_header_filter = ngx_http_header_filter;
return NGX_OK;
}
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