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Files
apache/modules/proxy/proxy_http.c
Jeff Trawick 9a1842b70c get basic HTTP proxy working on EBCDIC machines
(I would bet that there is more work to do throughout proxy, but at least
it can serve some pages now)


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@94811 13f79535-47bb-0310-9956-ffa450edef68
2002-04-26 12:29:38 +00:00

1090 lines
43 KiB
C

/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000-2002 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* Portions of this software are based upon public domain software
* originally written at the National Center for Supercomputing Applications,
* University of Illinois, Urbana-Champaign.
*/
/* HTTP routines for Apache proxy */
#include "mod_proxy.h"
module AP_MODULE_DECLARE_DATA proxy_http_module;
int ap_proxy_http_canon(request_rec *r, char *url);
int ap_proxy_http_handler(request_rec *r, proxy_server_conf *conf,
char *url, const char *proxyname,
apr_port_t proxyport);
typedef struct {
const char *name;
apr_port_t port;
apr_sockaddr_t *addr;
apr_socket_t *sock;
int close;
} proxy_http_conn_t;
static apr_status_t ap_proxy_http_cleanup(request_rec *r,
proxy_http_conn_t *p_conn,
proxy_conn_rec *backend);
/*
* Canonicalise http-like URLs.
* scheme is the scheme for the URL
* url is the URL starting with the first '/'
* def_port is the default port for this scheme.
*/
int ap_proxy_http_canon(request_rec *r, char *url)
{
char *host, *path, *search, sport[7];
const char *err;
const char *scheme;
apr_port_t port, def_port;
/* ap_default_port_for_scheme() */
if (strncasecmp(url, "http:", 5) == 0) {
url += 5;
scheme = "http";
}
else if (strncasecmp(url, "https:", 6) == 0) {
url += 6;
scheme = "https";
}
else {
return DECLINED;
}
def_port = apr_uri_default_port_for_scheme(scheme);
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: HTTP: canonicalising URL %s", url);
/* do syntatic check.
* We break the URL into host, port, path, search
*/
port = def_port;
err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
if (err)
return HTTP_BAD_REQUEST;
/* now parse path/search args, according to rfc1738 */
/* N.B. if this isn't a true proxy request, then the URL _path_
* has already been decoded. True proxy requests have r->uri
* == r->unparsed_uri, and no others have that property.
*/
if (r->uri == r->unparsed_uri) {
search = strchr(url, '?');
if (search != NULL)
*(search++) = '\0';
}
else
search = r->args;
/* process path */
path = ap_proxy_canonenc(r->pool, url, strlen(url), enc_path, r->proxyreq);
if (path == NULL)
return HTTP_BAD_REQUEST;
if (port != def_port)
apr_snprintf(sport, sizeof(sport), ":%d", port);
else
sport[0] = '\0';
r->filename = apr_pstrcat(r->pool, "proxy:", scheme, "://", host, sport,
"/", path, (search) ? "?" : "", (search) ? search : "", NULL);
return OK;
}
static const char *ap_proxy_location_reverse_map(request_rec *r, proxy_server_conf *conf, const char *url)
{
struct proxy_alias *ent;
int i, l1, l2;
char *u;
/* XXX FIXME: Make sure this handled the ambiguous case of the :80
* after the hostname */
l1 = strlen(url);
ent = (struct proxy_alias *)conf->raliases->elts;
for (i = 0; i < conf->raliases->nelts; i++) {
l2 = strlen(ent[i].real);
if (l1 >= l2 && strncmp(ent[i].real, url, l2) == 0) {
u = apr_pstrcat(r->pool, ent[i].fake, &url[l2], NULL);
return ap_construct_url(r->pool, u, r);
}
}
return url;
}
/* Clear all connection-based headers from the incoming headers table */
static void ap_proxy_clear_connection(apr_pool_t *p, apr_table_t *headers)
{
const char *name;
char *next = apr_pstrdup(p, apr_table_get(headers, "Connection"));
apr_table_unset(headers, "Proxy-Connection");
if (!next)
return;
while (*next) {
name = next;
while (*next && !apr_isspace(*next) && (*next != ',')) {
++next;
}
while (*next && (apr_isspace(*next) || (*next == ','))) {
*next = '\0';
++next;
}
apr_table_unset(headers, name);
}
apr_table_unset(headers, "Connection");
}
static
apr_status_t ap_proxy_http_determine_connection(apr_pool_t *p, request_rec *r,
proxy_http_conn_t *p_conn,
conn_rec *c,
proxy_server_conf *conf,
apr_uri_t *uri,
char **url,
const char *proxyname,
apr_port_t proxyport,
char *server_portstr,
int server_portstr_size) {
int server_port;
apr_status_t err;
apr_sockaddr_t *uri_addr;
/*
* Break up the URL to determine the host to connect to
*/
/* we break the URL into host, port, uri */
if (APR_SUCCESS != apr_uri_parse(p, *url, uri)) {
return ap_proxyerror(r, HTTP_BAD_REQUEST,
apr_pstrcat(p,"URI cannot be parsed: ", *url,
NULL));
}
if (!uri->port) {
uri->port = apr_uri_default_port_for_scheme(uri->scheme);
}
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: HTTP connecting %s to %s:%d", *url, uri->hostname,
uri->port);
/* do a DNS lookup for the destination host */
/* see memory note above */
err = apr_sockaddr_info_get(&uri_addr, apr_pstrdup(c->pool, uri->hostname),
APR_UNSPEC, uri->port, 0, c->pool);
/* allocate these out of the connection pool - the check on
* r->connection->id makes sure that this string does not get accessed
* past the connection lifetime */
/* are we connecting directly, or via a proxy? */
if (proxyname) {
p_conn->name = apr_pstrdup(c->pool, proxyname);
p_conn->port = proxyport;
/* see memory note above */
err = apr_sockaddr_info_get(&p_conn->addr, p_conn->name, APR_UNSPEC,
p_conn->port, 0, c->pool);
} else {
p_conn->name = apr_pstrdup(c->pool, uri->hostname);
p_conn->port = uri->port;
p_conn->addr = uri_addr;
*url = apr_pstrcat(p, uri->path, uri->query ? "?" : "",
uri->query ? uri->query : "",
uri->fragment ? "#" : "",
uri->fragment ? uri->fragment : "", NULL);
}
if (err != APR_SUCCESS) {
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
apr_pstrcat(p, "DNS lookup failure for: ",
p_conn->name, NULL));
}
/* Get the server port for the Via headers */
{
server_port = ap_get_server_port(r);
if (ap_is_default_port(server_port, r)) {
strcpy(server_portstr,"");
} else {
apr_snprintf(server_portstr, server_portstr_size, ":%d",
server_port);
}
}
/* check if ProxyBlock directive on this host */
if (OK != ap_proxy_checkproxyblock(r, conf, uri_addr)) {
return ap_proxyerror(r, HTTP_FORBIDDEN,
"Connect to remote machine blocked");
}
return OK;
}
static
apr_status_t ap_proxy_http_create_connection(apr_pool_t *p, request_rec *r,
proxy_http_conn_t *p_conn,
conn_rec *c, conn_rec **origin,
proxy_conn_rec *backend,
proxy_server_conf *conf,
const char *proxyname) {
int failed=0, new=0;
apr_socket_t *client_socket = NULL;
/* We have determined who to connect to. Now make the connection, supporting
* a KeepAlive connection.
*/
/* get all the possible IP addresses for the destname and loop through them
* until we get a successful connection
*/
/* if a keepalive socket is already open, check whether it must stay
* open, or whether it should be closed and a new socket created.
*/
/* see memory note above */
if (backend->connection) {
client_socket = ap_get_module_config(backend->connection->conn_config, &core_module);
if ((backend->connection->id == c->id) &&
(backend->port == p_conn->port) &&
(backend->hostname) &&
(!apr_strnatcasecmp(backend->hostname, p_conn->name))) {
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: keepalive address match (keep original socket)");
} else {
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: keepalive address mismatch / connection has"
" changed (close old socket (%s/%s, %d/%d))",
p_conn->name, backend->hostname, p_conn->port,
backend->port);
apr_socket_close(client_socket);
backend->connection = NULL;
}
}
/* get a socket - either a keepalive one, or a new one */
new = 1;
if ((backend->connection) && (backend->connection->id == c->id)) {
apr_size_t buffer_len = 1;
char test_buffer[1];
apr_status_t socket_status;
apr_int32_t current_timeout;
/* use previous keepalive socket */
*origin = backend->connection;
p_conn->sock = client_socket;
new = 0;
/* save timeout */
apr_getsocketopt(p_conn->sock, APR_SO_TIMEOUT, &current_timeout);
/* set no timeout */
apr_setsocketopt(p_conn->sock, APR_SO_TIMEOUT, 0);
socket_status = apr_recv(p_conn->sock, test_buffer, &buffer_len);
/* put back old timeout */
apr_setsocketopt(p_conn->sock, APR_SO_TIMEOUT, current_timeout);
if ( APR_STATUS_IS_EOF(socket_status) ) {
ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, NULL,
"proxy: HTTP: previous connection is closed");
new = 1;
}
}
if (new) {
/* create a new socket */
backend->connection = NULL;
/*
* At this point we have a list of one or more IP addresses of
* the machine to connect to. If configured, reorder this
* list so that the "best candidate" is first try. "best
* candidate" could mean the least loaded server, the fastest
* responding server, whatever.
*
* For now we do nothing, ie we get DNS round robin.
* XXX FIXME
*/
failed = ap_proxy_connect_to_backend(&p_conn->sock, "HTTP",
p_conn->addr, p_conn->name,
conf, r->server, c->pool);
/* handle a permanent error on the connect */
if (failed) {
if (proxyname) {
return DECLINED;
} else {
return HTTP_BAD_GATEWAY;
}
}
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: socket is connected");
/* the socket is now open, create a new backend server connection */
*origin = ap_run_create_connection(c->pool, r->server, p_conn->sock,
r->connection->id,
r->connection->sbh, c->bucket_alloc);
if (!origin) {
/* the peer reset the connection already; ap_run_create_connection()
* closed the socket
*/
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0,
r->server, "proxy: an error occurred creating a "
"new connection to %pI (%s)", p_conn->addr,
p_conn->name);
apr_socket_close(p_conn->sock);
return HTTP_INTERNAL_SERVER_ERROR;
}
backend->connection = *origin;
backend->hostname = apr_pstrdup(c->pool, p_conn->name);
backend->port = p_conn->port;
if (backend->is_ssl) {
if (!ap_proxy_ssl_enable(backend->connection)) {
ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0,
r->server, "proxy: failed to enable ssl support "
"for %pI (%s)", p_conn->addr, p_conn->name);
return HTTP_INTERNAL_SERVER_ERROR;
}
}
else {
ap_proxy_ssl_disable(backend->connection);
}
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: connection complete to %pI (%s)",
p_conn->addr, p_conn->name);
/* set up the connection filters */
ap_run_pre_connection(*origin, p_conn->sock);
}
return OK;
}
static
apr_status_t ap_proxy_http_request(apr_pool_t *p, request_rec *r,
proxy_http_conn_t *p_conn, conn_rec *origin,
proxy_server_conf *conf,
apr_uri_t *uri,
char *url, apr_bucket_brigade *bb,
char *server_portstr) {
conn_rec *c = r->connection;
char buffer[HUGE_STRING_LEN];
char *buf;
apr_bucket *e;
const apr_array_header_t *headers_in_array;
const apr_table_entry_t *headers_in;
int counter;
apr_status_t status;
/*
* Send the HTTP/1.1 request to the remote server
*/
/* strip connection listed hop-by-hop headers from the request */
/* even though in theory a connection: close coming from the client
* should not affect the connection to the server, it's unlikely
* that subsequent client requests will hit this thread/process, so
* we cancel server keepalive if the client does.
*/
p_conn->close += ap_proxy_liststr(apr_table_get(r->headers_in,
"Connection"), "close");
/* sub-requests never use keepalives */
if (r->main) {
p_conn->close++;
}
ap_proxy_clear_connection(p, r->headers_in);
if (p_conn->close) {
apr_table_setn(r->headers_in, "Connection", "close");
origin->keepalive = 0;
}
buf = apr_pstrcat(p, r->method, " ", url, " HTTP/1.1" CRLF, NULL);
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
if ( conf->preserve_host == 0 ) {
if (uri->port_str && uri->port != DEFAULT_HTTP_PORT) {
buf = apr_pstrcat(p, "Host: ", uri->hostname, ":", uri->port_str, CRLF,
NULL);
} else {
buf = apr_pstrcat(p, "Host: ", uri->hostname, CRLF, NULL);
}
}
else {
/* don't want to use r->hostname, as the incoming header might have a
* port attached
*/
const char* hostname = apr_table_get(r->headers_in,"Host");
if (!hostname) {
hostname = r->server->server_hostname;
ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, r,
"proxy: no HTTP 0.9 request (with no host line) "
"on incoming request and preserve host set "
"forcing hostname to be %s for uri %s",
hostname,
r->uri );
}
buf = apr_pstrcat(p, "Host: ", hostname, CRLF, NULL);
}
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
/* handle Via */
if (conf->viaopt == via_block) {
/* Block all outgoing Via: headers */
apr_table_unset(r->headers_in, "Via");
} else if (conf->viaopt != via_off) {
/* Create a "Via:" request header entry and merge it */
/* Generate outgoing Via: header with/without server comment: */
apr_table_mergen(r->headers_in, "Via",
(conf->viaopt == via_full)
? apr_psprintf(p, "%d.%d %s%s (%s)",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
ap_get_server_name(r), server_portstr,
AP_SERVER_BASEVERSION)
: apr_psprintf(p, "%d.%d %s%s",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
ap_get_server_name(r), server_portstr)
);
}
/* X-Forwarded-*: handling
*
* XXX Privacy Note:
* -----------------
*
* These request headers are only really useful when the mod_proxy
* is used in a reverse proxy configuration, so that useful info
* about the client can be passed through the reverse proxy and on
* to the backend server, which may require the information to
* function properly.
*
* In a forward proxy situation, these options are a potential
* privacy violation, as information about clients behind the proxy
* are revealed to arbitrary servers out there on the internet.
*
* The HTTP/1.1 Via: header is designed for passing client
* information through proxies to a server, and should be used in
* a forward proxy configuation instead of X-Forwarded-*. See the
* ProxyVia option for details.
*/
if (PROXYREQ_REVERSE == r->proxyreq) {
const char *buf;
/* Add X-Forwarded-For: so that the upstream has a chance to
* determine, where the original request came from.
*/
apr_table_mergen(r->headers_in, "X-Forwarded-For",
r->connection->remote_ip);
/* Add X-Forwarded-Host: so that upstream knows what the
* original request hostname was.
*/
if ((buf = apr_table_get(r->headers_in, "Host"))) {
apr_table_mergen(r->headers_in, "X-Forwarded-Host", buf);
}
/* Add X-Forwarded-Server: so that upstream knows what the
* name of this proxy server is (if there are more than one)
* XXX: This duplicates Via: - do we strictly need it?
*/
apr_table_mergen(r->headers_in, "X-Forwarded-Server",
r->server->server_hostname);
}
/* send request headers */
proxy_run_fixups(r);
headers_in_array = apr_table_elts(r->headers_in);
headers_in = (const apr_table_entry_t *) headers_in_array->elts;
for (counter = 0; counter < headers_in_array->nelts; counter++) {
if (headers_in[counter].key == NULL || headers_in[counter].val == NULL
/* Clear out hop-by-hop request headers not to send
* RFC2616 13.5.1 says we should strip these headers
*/
/* Already sent */
|| !apr_strnatcasecmp(headers_in[counter].key, "Host")
|| !apr_strnatcasecmp(headers_in[counter].key, "Keep-Alive")
|| !apr_strnatcasecmp(headers_in[counter].key, "TE")
|| !apr_strnatcasecmp(headers_in[counter].key, "Trailer")
|| !apr_strnatcasecmp(headers_in[counter].key, "Transfer-Encoding")
|| !apr_strnatcasecmp(headers_in[counter].key, "Upgrade")
/* XXX: @@@ FIXME: "Proxy-Authorization" should *only* be
* suppressed if THIS server requested the authentication,
* not when a frontend proxy requested it!
*
* The solution to this problem is probably to strip out
* the Proxy-Authorisation header in the authorisation
* code itself, not here. This saves us having to signal
* somehow whether this request was authenticated or not.
*/
|| !apr_strnatcasecmp(headers_in[counter].key,"Proxy-Authorization")
|| !apr_strnatcasecmp(headers_in[counter].key,"Proxy-Authenticate")) {
continue;
}
/* for sub-requests, ignore freshness/expiry headers */
if (r->main) {
if (headers_in[counter].key == NULL || headers_in[counter].val == NULL
|| !apr_strnatcasecmp(headers_in[counter].key, "If-Match")
|| !apr_strnatcasecmp(headers_in[counter].key, "If-Modified-Since")
|| !apr_strnatcasecmp(headers_in[counter].key, "If-Range")
|| !apr_strnatcasecmp(headers_in[counter].key, "If-Unmodified-Since")
|| !apr_strnatcasecmp(headers_in[counter].key, "If-None-Match")) {
continue;
}
}
buf = apr_pstrcat(p, headers_in[counter].key, ": ",
headers_in[counter].val, CRLF,
NULL);
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), p, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
}
/* add empty line at the end of the headers */
#if APR_CHARSET_EBCDIC
e = apr_bucket_immortal_create("\015\012", 2, c->bucket_alloc);
#else
e = apr_bucket_immortal_create(CRLF, sizeof(CRLF)-1, c->bucket_alloc);
#endif
APR_BRIGADE_INSERT_TAIL(bb, e);
e = apr_bucket_flush_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
status = ap_pass_brigade(origin->output_filters, bb);
if (status != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
"proxy: request failed to %pI (%s)",
p_conn->addr, p_conn->name);
return status;
}
/* send the request data, if any. */
if (ap_should_client_block(r)) {
while ((counter = ap_get_client_block(r, buffer, sizeof(buffer))) > 0) {
e = apr_bucket_pool_create(buffer, counter, p, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
e = apr_bucket_flush_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
status = ap_pass_brigade(origin->output_filters, bb);
if (status != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_ERR, status, r->server,
"proxy: pass request data failed to %pI (%s)",
p_conn->addr, p_conn->name);
return status;
}
apr_brigade_cleanup(bb);
}
}
return APR_SUCCESS;
}
static
apr_status_t ap_proxy_http_process_response(apr_pool_t * p, request_rec *r,
proxy_http_conn_t *p_conn,
conn_rec *origin,
proxy_conn_rec *backend,
proxy_server_conf *conf,
apr_bucket_brigade *bb,
char *server_portstr) {
conn_rec *c = r->connection;
char buffer[HUGE_STRING_LEN];
request_rec *rp;
apr_bucket *e;
int len, backasswards;
int received_continue = 1; /* flag to indicate if we should
* loop over response parsing logic
* in the case that the origin told us
* to HTTP_CONTINUE
*/
/* Get response from the remote server, and pass it up the
* filter chain
*/
rp = ap_proxy_make_fake_req(origin, r);
while (received_continue) {
apr_brigade_cleanup(bb);
len = ap_getline(buffer, sizeof(buffer), rp, 0);
if (len == 0) {
/* handle one potential stray CRLF */
len = ap_getline(buffer, sizeof(buffer), rp, 0);
}
if (len <= 0) {
apr_socket_close(p_conn->sock);
backend->connection = NULL;
ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, r,
"proxy: error reading status line from remote "
"server %s", p_conn->name);
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
"Error reading from remote server");
}
/* Is it an HTTP/1 response?
* This is buggy if we ever see an HTTP/1.10
*/
if (apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
int major, minor;
if (2 != sscanf(buffer, "HTTP/%u.%u", &major, &minor)) {
major = 1;
minor = 1;
}
/* If not an HTTP/1 message or
* if the status line was > 8192 bytes
*/
else if ((buffer[5] != '1') || (len >= sizeof(buffer)-1)) {
apr_socket_close(p_conn->sock);
backend->connection = NULL;
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
apr_pstrcat(p, "Corrupt status line returned by remote "
"server: ", buffer, NULL));
}
backasswards = 0;
buffer[12] = '\0';
r->status = atoi(&buffer[9]);
buffer[12] = ' ';
r->status_line = apr_pstrdup(p, &buffer[9]);
/* read the headers. */
/* N.B. for HTTP/1.0 clients, we have to fold line-wrapped headers*/
/* Also, take care with headers with multiple occurences. */
r->headers_out = ap_proxy_read_headers(r, rp, buffer,
sizeof(buffer), origin);
if (r->headers_out == NULL) {
ap_log_error(APLOG_MARK, APLOG_WARNING|APLOG_NOERRNO, 0,
r->server, "proxy: bad HTTP/%d.%d header "
"returned by %s (%s)", major, minor, r->uri,
r->method);
p_conn->close += 1;
/*
* ap_send_error relies on a headers_out to be present. we
* are in a bad position here.. so force everything we send out
* to have nothing to do with the incoming packet
*/
r->headers_out = apr_table_make(r->pool,1);
r->status = HTTP_BAD_GATEWAY;
r->status_line = "bad gateway";
return r->status;
} else {
/* strip connection listed hop-by-hop headers from response */
const char *buf;
p_conn->close += ap_proxy_liststr(apr_table_get(r->headers_out,
"Connection"),
"close");
ap_proxy_clear_connection(p, r->headers_out);
if ((buf = apr_table_get(r->headers_out, "Content-Type"))) {
ap_set_content_type(r, apr_pstrdup(p, buf));
}
ap_proxy_pre_http_request(origin,rp);
}
/* handle Via header in response */
if (conf->viaopt != via_off && conf->viaopt != via_block) {
/* create a "Via:" response header entry and merge it */
ap_table_mergen(r->headers_out, "Via",
(conf->viaopt == via_full)
? apr_psprintf(p, "%d.%d %s%s (%s)",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
ap_get_server_name(r),
server_portstr,
AP_SERVER_BASEVERSION)
: apr_psprintf(p, "%d.%d %s%s",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
ap_get_server_name(r),
server_portstr)
);
}
/* cancel keepalive if HTTP/1.0 or less */
if ((major < 1) || (minor < 1)) {
p_conn->close += 1;
origin->keepalive = 0;
}
} else {
/* an http/0.9 response */
backasswards = 1;
r->status = 200;
r->status_line = "200 OK";
p_conn->close += 1;
}
if ( r->status != HTTP_CONTINUE ) {
received_continue = 0;
} else {
ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_DEBUG, 0, NULL,
"proxy: HTTP: received 100 CONTINUE");
}
/* we must accept 3 kinds of date, but generate only 1 kind of date */
{
const char *buf;
if ((buf = apr_table_get(r->headers_out, "Date")) != NULL) {
apr_table_set(r->headers_out, "Date",
ap_proxy_date_canon(p, buf));
}
if ((buf = apr_table_get(r->headers_out, "Expires")) != NULL) {
apr_table_set(r->headers_out, "Expires",
ap_proxy_date_canon(p, buf));
}
if ((buf = apr_table_get(r->headers_out, "Last-Modified")) != NULL) {
apr_table_set(r->headers_out, "Last-Modified",
ap_proxy_date_canon(p, buf));
}
}
/* munge the Location and URI response headers according to
* ProxyPassReverse
*/
{
const char *buf;
if ((buf = apr_table_get(r->headers_out, "Location")) != NULL) {
apr_table_set(r->headers_out, "Location",
ap_proxy_location_reverse_map(r, conf, buf));
}
if ((buf = apr_table_get(r->headers_out, "Content-Location")) != NULL) {
apr_table_set(r->headers_out, "Content-Location",
ap_proxy_location_reverse_map(r, conf, buf));
}
if ((buf = apr_table_get(r->headers_out, "URI")) != NULL) {
apr_table_set(r->headers_out, "URI",
ap_proxy_location_reverse_map(r, conf, buf));
}
}
r->sent_bodyct = 1;
/* Is it an HTTP/0.9 response? If so, send the extra data */
if (backasswards) {
apr_ssize_t cntr = len;
e = apr_bucket_heap_create(buffer, cntr, NULL, c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
}
/* send body - but only if a body is expected */
if ((!r->header_only) && /* not HEAD request */
(r->status > 199) && /* not any 1xx response */
(r->status != HTTP_NO_CONTENT) && /* not 204 */
(r->status != HTTP_RESET_CONTENT) && /* not 205 */
(r->status != HTTP_NOT_MODIFIED)) { /* not 304 */
/* We need to copy the output headers and treat them as input
* headers as well. BUT, we need to do this before we remove
* TE and C-L, so that they are preserved accordingly for
* ap_http_filter to know where to end.
*/
rp->headers_in = apr_table_copy(r->pool, r->headers_out);
/* In order for ap_set_keepalive to work properly, we can NOT
* have any length information stored in the output headers.
*/
apr_table_unset(r->headers_out,"Transfer-Encoding");
apr_table_unset(r->headers_out,"Content-Length");
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: start body send");
/*
* if we are overriding the errors, we can't put the content
* of the page into the brigade
*/
if ( (conf->error_override ==0) || r->status < 400 ) {
/* read the body, pass it to the output filters */
int finish = FALSE;
while (ap_get_brigade(rp->input_filters,
bb,
AP_MODE_READBYTES,
APR_BLOCK_READ,
conf->io_buffer_size) == APR_SUCCESS) {
#if DEBUGGING
{
apr_off_t readbytes;
apr_brigade_length(bb, 0, &readbytes);
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0,
r->server, "proxy (PID %d): readbytes: %#x",
getpid(), readbytes);
}
#endif
/* sanity check */
if (APR_BRIGADE_EMPTY(bb)) {
apr_brigade_cleanup(bb);
break;
}
/* found the last brigade? */
if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) {
/* if this is the last brigade, cleanup the
* backend connection first to prevent the
* backend server from hanging around waiting
* for a slow client to eat these bytes
*/
ap_proxy_http_cleanup(r, p_conn, backend);
/* signal that we must leave */
finish = TRUE;
}
/* try send what we read */
if (ap_pass_brigade(r->output_filters, bb) != APR_SUCCESS) {
/* Ack! Phbtt! Die! User aborted! */
p_conn->close = 1; /* this causes socket close below */
finish = TRUE;
}
/* make sure we always clean up after ourselves */
apr_brigade_cleanup(bb);
/* if we are done, leave */
if (TRUE == finish) {
break;
}
}
}
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: end body send");
} else {
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: header only");
}
}
if ( conf->error_override ) {
/* the code above this checks for 'OK' which is what the hook expects */
if ( r->status == HTTP_OK )
return OK;
else {
/* clear r->status for override error, otherwise ErrorDocument
* thinks that this is a recursive error, and doesn't find the
* custom error page
*/
int status = r->status;
r->status = HTTP_OK;
return status;
}
} else
return OK;
}
static
apr_status_t ap_proxy_http_cleanup(request_rec *r, proxy_http_conn_t *p_conn,
proxy_conn_rec *backend) {
/* If there are no KeepAlives, or if the connection has been signalled
* to close, close the socket and clean up
*/
/* if the connection is < HTTP/1.1, or Connection: close,
* we close the socket, otherwise we leave it open for KeepAlive support
*/
if (p_conn->close || (r->proto_num < HTTP_VERSION(1,1))) {
if (p_conn->sock) {
apr_socket_close(p_conn->sock);
p_conn->sock = NULL;
backend->connection = NULL;
}
}
return OK;
}
/*
* This handles http:// URLs, and other URLs using a remote proxy over http
* If proxyhost is NULL, then contact the server directly, otherwise
* go via the proxy.
* Note that if a proxy is used, then URLs other than http: can be accessed,
* also, if we have trouble which is clearly specific to the proxy, then
* we return DECLINED so that we can try another proxy. (Or the direct
* route.)
*/
int ap_proxy_http_handler(request_rec *r, proxy_server_conf *conf,
char *url, const char *proxyname,
apr_port_t proxyport)
{
int status;
char server_portstr[32];
conn_rec *origin = NULL;
proxy_conn_rec *backend = NULL;
int is_ssl = 0;
/* Note: Memory pool allocation.
* A downstream keepalive connection is always connected to the existence
* (or not) of an upstream keepalive connection. If this is not done then
* load balancing against multiple backend servers breaks (one backend
* server ends up taking 100% of the load), and the risk is run of
* downstream keepalive connections being kept open unnecessarily. This
* keeps webservers busy and ties up resources.
*
* As a result, we allocate all sockets out of the upstream connection
* pool, and when we want to reuse a socket, we check first whether the
* connection ID of the current upstream connection is the same as that
* of the connection when the socket was opened.
*/
apr_pool_t *p = r->connection->pool;
conn_rec *c = r->connection;
apr_bucket_brigade *bb = apr_brigade_create(p, c->bucket_alloc);
apr_uri_t *uri = apr_palloc(r->connection->pool, sizeof(*uri));
proxy_http_conn_t *p_conn = apr_pcalloc(r->connection->pool,
sizeof(*p_conn));
/* is it for us? */
if (strncasecmp(url, "https:", 6) == 0) {
if (!ap_proxy_ssl_enable(NULL)) {
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: HTTPS: declining URL %s"
" (mod_ssl not configured?)", url);
return DECLINED;
}
is_ssl = 1;
}
else if (strncasecmp(url, "http:", 5)) {
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: HTTP: declining URL %s", url);
return DECLINED; /* only interested in HTTP */
}
ap_log_error(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, r->server,
"proxy: HTTP: serving URL %s", url);
/* only use stored info for top-level pages. Sub requests don't share
* in keepalives
*/
if (!r->main) {
backend = (proxy_conn_rec *) ap_get_module_config(c->conn_config,
&proxy_http_module);
}
/* create space for state information */
if (!backend) {
backend = ap_pcalloc(c->pool, sizeof(proxy_conn_rec));
backend->connection = NULL;
backend->hostname = NULL;
backend->port = 0;
if (!r->main) {
ap_set_module_config(c->conn_config, &proxy_http_module, backend);
}
}
backend->is_ssl = is_ssl;
/* Step One: Determine Who To Connect To */
status = ap_proxy_http_determine_connection(p, r, p_conn, c, conf, uri,
&url, proxyname, proxyport,
server_portstr,
sizeof(server_portstr));
if ( status != OK ) {
return status;
}
/* Step Two: Make the Connection */
status = ap_proxy_http_create_connection(p, r, p_conn, c, &origin, backend,
conf, proxyname);
if ( status != OK ) {
return status;
}
/* Step Three: Send the Request */
status = ap_proxy_http_request(p, r, p_conn, origin, conf, uri, url, bb,
server_portstr);
if ( status != OK ) {
return status;
}
/* Step Four: Receive the Response */
status = ap_proxy_http_process_response(p, r, p_conn, origin, backend, conf,
bb, server_portstr);
if ( status != OK ) {
/* clean up even if there is an error */
ap_proxy_http_cleanup(r, p_conn, backend);
return status;
}
/* Step Five: Clean Up */
status = ap_proxy_http_cleanup(r, p_conn, backend);
if ( status != OK ) {
return status;
}
return OK;
}
static void ap_proxy_http_register_hook(apr_pool_t *p)
{
proxy_hook_scheme_handler(ap_proxy_http_handler, NULL, NULL, APR_HOOK_FIRST);
proxy_hook_canon_handler(ap_proxy_http_canon, NULL, NULL, APR_HOOK_FIRST);
}
module AP_MODULE_DECLARE_DATA proxy_http_module = {
STANDARD20_MODULE_STUFF,
NULL, /* create per-directory config structure */
NULL, /* merge per-directory config structures */
NULL, /* create per-server config structure */
NULL, /* merge per-server config structures */
NULL, /* command apr_table_t */
ap_proxy_http_register_hook/* register hooks */
};