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86ef235216
cve-2024-38477/httpd-2.4.59/modules/proxy/mod_proxy_http.c
gbucchino 86ef235216 First commit
2025-06-05 15:09:30 +02:00

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/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* HTTP routines for Apache proxy */
#include "mod_proxy.h"
#include "ap_regex.h"
module AP_MODULE_DECLARE_DATA proxy_http_module;
static int (*ap_proxy_clear_connection_fn)(request_rec *r, apr_table_t *headers) =
NULL;
static apr_status_t ap_proxy_http_cleanup(const char *scheme,
request_rec *r,
proxy_conn_rec *backend);
static apr_status_t ap_proxygetline(apr_bucket_brigade *bb, char *s, int n,
request_rec *r, int flags, int *read);
static const char *get_url_scheme(const char **url, int *is_ssl)
{
const char *u = *url;
switch (u[0]) {
case 'h':
case 'H':
if (strncasecmp(u + 1, "ttp", 3) == 0) {
if (u[4] == ':') {
*is_ssl = 0;
*url = u + 5;
return "http";
}
if (apr_tolower(u[4]) == 's' && u[5] == ':') {
*is_ssl = 1;
*url = u + 6;
return "https";
}
}
break;
case 'w':
case 'W':
if (apr_tolower(u[1]) == 's') {
if (u[2] == ':') {
*is_ssl = 0;
*url = u + 3;
return "ws";
}
if (apr_tolower(u[2]) == 's' && u[3] == ':') {
*is_ssl = 1;
*url = u + 4;
return "wss";
}
}
break;
}
*is_ssl = 0;
return NULL;
}
/*
* Canonicalise http-like URLs.
* scheme is the scheme for the URL
* url is the URL starting with the first '/'
*/
static int proxy_http_canon(request_rec *r, char *url)
{
const char *base_url = url;
char *host, *path, sport[7];
char *search = NULL;
const char *err;
const char *scheme;
apr_port_t port, def_port;
int is_ssl = 0;
scheme = get_url_scheme((const char **)&url, &is_ssl);
if (!scheme) {
return DECLINED;
}
port = def_port = (is_ssl) ? DEFAULT_HTTPS_PORT : DEFAULT_HTTP_PORT;
ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r,
"HTTP: canonicalising URL %s", base_url);
/* do syntatic check.
* We break the URL into host, port, path, search
*/
err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
if (err) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01083)
"error parsing URL %s: %s", base_url, err);
return HTTP_BAD_REQUEST;
}
/*
* now parse path/search args, according to rfc1738:
* process the path.
*
* In a reverse proxy, our URL has been processed, so canonicalise
* unless proxy-nocanon is set to say it's raw
* In a forward proxy, we have and MUST NOT MANGLE the original.
*/
switch (r->proxyreq) {
default: /* wtf are we doing here? */
case PROXYREQ_REVERSE:
if (apr_table_get(r->notes, "proxy-nocanon")) {
path = url; /* this is the raw path */
}
else if (apr_table_get(r->notes, "proxy-noencode")) {
path = url; /* this is the encoded path already */
search = r->args;
}
else {
core_dir_config *d = ap_get_core_module_config(r->per_dir_config);
int flags = d->allow_encoded_slashes && !d->decode_encoded_slashes ? PROXY_CANONENC_NOENCODEDSLASHENCODING : 0;
path = ap_proxy_canonenc_ex(r->pool, url, strlen(url), enc_path,
flags, r->proxyreq);
if (!path) {
return HTTP_BAD_REQUEST;
}
search = r->args;
}
break;
case PROXYREQ_PROXY:
path = url;
break;
}
/*
* If we have a raw control character or a ' ' in nocanon path or
* r->args, correct encoding was missed.
*/
if (path == url && *ap_scan_vchar_obstext(path)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10415)
"To be forwarded path contains control "
"characters or spaces");
return HTTP_FORBIDDEN;
}
if (search && *ap_scan_vchar_obstext(search)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10408)
"To be forwarded query string contains control "
"characters or spaces");
return HTTP_FORBIDDEN;
}
if (port != def_port)
apr_snprintf(sport, sizeof(sport), ":%d", port);
else
sport[0] = '\0';
if (ap_strchr_c(host, ':')) { /* if literal IPv6 address */
host = apr_pstrcat(r->pool, "[", host, "]", NULL);
}
r->filename = apr_pstrcat(r->pool, "proxy:", scheme, "://", host, sport,
"/", path, (search) ? "?" : "", search, NULL);
return OK;
}
/* Clear all connection-based headers from the incoming headers table */
typedef struct header_dptr {
apr_pool_t *pool;
apr_table_t *table;
apr_time_t time;
} header_dptr;
static ap_regex_t *warn_rx;
static int clean_warning_headers(void *data, const char *key, const char *val)
{
apr_table_t *headers = ((header_dptr*)data)->table;
apr_pool_t *pool = ((header_dptr*)data)->pool;
char *warning;
char *date;
apr_time_t warn_time;
const int nmatch = 3;
ap_regmatch_t pmatch[3];
if (headers == NULL) {
((header_dptr*)data)->table = headers = apr_table_make(pool, 2);
}
/*
* Parse this, suckers!
*
* Warning = "Warning" ":" 1#warning-value
*
* warning-value = warn-code SP warn-agent SP warn-text
* [SP warn-date]
*
* warn-code = 3DIGIT
* warn-agent = ( host [ ":" port ] ) | pseudonym
* ; the name or pseudonym of the server adding
* ; the Warning header, for use in debugging
* warn-text = quoted-string
* warn-date = <"> HTTP-date <">
*
* Buggrit, use a bloomin' regexp!
* (\d{3}\s+\S+\s+\".*?\"(\s+\"(.*?)\")?) --> whole in $1, date in $3
*/
while (!ap_regexec(warn_rx, val, nmatch, pmatch, 0)) {
warning = apr_pstrndup(pool, val+pmatch[0].rm_so,
pmatch[0].rm_eo - pmatch[0].rm_so);
warn_time = 0;
if (pmatch[2].rm_eo > pmatch[2].rm_so) {
/* OK, we have a date here */
date = apr_pstrndup(pool, val+pmatch[2].rm_so,
pmatch[2].rm_eo - pmatch[2].rm_so);
warn_time = apr_date_parse_http(date);
}
if (!warn_time || (warn_time == ((header_dptr*)data)->time)) {
apr_table_addn(headers, key, warning);
}
val += pmatch[0].rm_eo;
}
return 1;
}
static apr_table_t *ap_proxy_clean_warnings(apr_pool_t *p, apr_table_t *headers)
{
header_dptr x;
x.pool = p;
x.table = NULL;
x.time = apr_date_parse_http(apr_table_get(headers, "Date"));
apr_table_do(clean_warning_headers, &x, headers, "Warning", NULL);
if (x.table != NULL) {
apr_table_unset(headers, "Warning");
return apr_table_overlay(p, headers, x.table);
}
else {
return headers;
}
}
static void add_te_chunked(apr_pool_t *p,
apr_bucket_alloc_t *bucket_alloc,
apr_bucket_brigade *header_brigade)
{
apr_bucket *e;
char *buf;
const char te_hdr[] = "Transfer-Encoding: chunked" CRLF;
buf = apr_pmemdup(p, te_hdr, sizeof(te_hdr)-1);
ap_xlate_proto_to_ascii(buf, sizeof(te_hdr)-1);
e = apr_bucket_pool_create(buf, sizeof(te_hdr)-1, p, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(header_brigade, e);
}
static void add_cl(apr_pool_t *p,
apr_bucket_alloc_t *bucket_alloc,
apr_bucket_brigade *header_brigade,
const char *cl_val)
{
apr_bucket *e;
char *buf;
buf = apr_pstrcat(p, "Content-Length: ",
cl_val,
CRLF,
NULL);
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), p, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(header_brigade, e);
}
#ifndef CRLF_ASCII
#define CRLF_ASCII "\015\012"
#endif
#ifndef ZERO_ASCII
#define ZERO_ASCII "\060"
#endif
#define MAX_MEM_SPOOL 16384
typedef enum {
RB_INIT = 0,
RB_STREAM_CL,
RB_STREAM_CHUNKED,
RB_SPOOL_CL
} rb_methods;
typedef struct {
apr_pool_t *p;
request_rec *r;
const char *proto;
proxy_worker *worker;
proxy_server_conf *sconf;
char server_portstr[32];
proxy_conn_rec *backend;
conn_rec *origin;
apr_bucket_alloc_t *bucket_alloc;
apr_bucket_brigade *header_brigade;
apr_bucket_brigade *input_brigade;
char *old_cl_val, *old_te_val;
apr_off_t cl_val;
rb_methods rb_method;
const char *upgrade;
unsigned int do_100_continue :1,
prefetch_nonblocking :1,
force10 :1;
} proxy_http_req_t;
static int stream_reqbody(proxy_http_req_t *req)
{
request_rec *r = req->r;
int seen_eos = 0, rv = OK;
apr_size_t hdr_len;
char chunk_hdr[20]; /* must be here due to transient bucket. */
conn_rec *origin = req->origin;
proxy_conn_rec *p_conn = req->backend;
apr_bucket_alloc_t *bucket_alloc = req->bucket_alloc;
apr_bucket_brigade *header_brigade = req->header_brigade;
apr_bucket_brigade *input_brigade = req->input_brigade;
rb_methods rb_method = req->rb_method;
apr_off_t bytes, bytes_streamed = 0;
apr_bucket *e;
do {
if (APR_BRIGADE_EMPTY(input_brigade)
&& APR_BRIGADE_EMPTY(header_brigade)) {
rv = ap_proxy_read_input(r, p_conn, input_brigade,
HUGE_STRING_LEN);
if (rv != OK) {
return rv;
}
}
if (!APR_BRIGADE_EMPTY(input_brigade)) {
/* If this brigade contains EOS, remove it and be done. */
if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
seen_eos = 1;
/* We can't pass this EOS to the output_filters. */
e = APR_BRIGADE_LAST(input_brigade);
apr_bucket_delete(e);
}
apr_brigade_length(input_brigade, 1, &bytes);
bytes_streamed += bytes;
if (rb_method == RB_STREAM_CHUNKED) {
if (bytes) {
/*
* Prepend the size of the chunk
*/
hdr_len = apr_snprintf(chunk_hdr, sizeof(chunk_hdr),
"%" APR_UINT64_T_HEX_FMT CRLF,
(apr_uint64_t)bytes);
ap_xlate_proto_to_ascii(chunk_hdr, hdr_len);
e = apr_bucket_transient_create(chunk_hdr, hdr_len,
bucket_alloc);
APR_BRIGADE_INSERT_HEAD(input_brigade, e);
/*
* Append the end-of-chunk CRLF
*/
e = apr_bucket_immortal_create(CRLF_ASCII, 2, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(input_brigade, e);
}
if (seen_eos) {
/*
* Append the tailing 0-size chunk
*/
e = apr_bucket_immortal_create(ZERO_ASCII CRLF_ASCII
/* <trailers> */
CRLF_ASCII,
5, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(input_brigade, e);
}
}
else if (rb_method == RB_STREAM_CL
&& (bytes_streamed > req->cl_val
|| (seen_eos && bytes_streamed < req->cl_val))) {
/* C-L != bytes streamed?!?
*
* Prevent HTTP Request/Response Splitting.
*
* We can't stream more (or less) bytes at the back end since
* they could be interpreted in separate requests (more bytes
* now would start a new request, less bytes would make the
* first bytes of the next request be part of the current one).
*
* It can't happen from the client connection here thanks to
* ap_http_filter(), but some module's filter may be playing
* bad games, hence the HTTP_INTERNAL_SERVER_ERROR.
*/
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01086)
"read %s bytes of request body than expected "
"(got %" APR_OFF_T_FMT ", expected "
"%" APR_OFF_T_FMT ")",
bytes_streamed > req->cl_val ? "more" : "less",
bytes_streamed, req->cl_val);
return HTTP_INTERNAL_SERVER_ERROR;
}
if (seen_eos && apr_table_get(r->subprocess_env,
"proxy-sendextracrlf")) {
e = apr_bucket_immortal_create(CRLF_ASCII, 2, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(input_brigade, e);
}
}
/* If we never sent the header brigade, go ahead and take care of
* that now by prepending it (once only since header_brigade will be
* empty afterward).
*/
APR_BRIGADE_PREPEND(input_brigade, header_brigade);
/* Flush here on EOS because we won't ap_proxy_read_input() again. */
rv = ap_proxy_pass_brigade(bucket_alloc, r, p_conn, origin,
input_brigade, seen_eos);
if (rv != OK) {
return rv;
}
} while (!seen_eos);
return OK;
}
static void terminate_headers(proxy_http_req_t *req)
{
apr_bucket_alloc_t *bucket_alloc = req->bucket_alloc;
apr_bucket *e;
char *buf;
/*
* Handle Connection: header if we do HTTP/1.1 request:
* If we plan to close the backend connection sent Connection: close
* otherwise sent Connection: Keep-Alive.
*/
if (!req->force10) {
if (req->upgrade) {
buf = apr_pstrdup(req->p, "Connection: Upgrade" CRLF);
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), req->p, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(req->header_brigade, e);
/* Tell the backend that it can upgrade the connection. */
buf = apr_pstrcat(req->p, "Upgrade: ", req->upgrade, CRLF, NULL);
}
else if (ap_proxy_connection_reusable(req->backend)) {
buf = apr_pstrdup(req->p, "Connection: Keep-Alive" CRLF);
}
else {
buf = apr_pstrdup(req->p, "Connection: close" CRLF);
}
ap_xlate_proto_to_ascii(buf, strlen(buf));
e = apr_bucket_pool_create(buf, strlen(buf), req->p, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(req->header_brigade, e);
}
/* add empty line at the end of the headers */
e = apr_bucket_immortal_create(CRLF_ASCII, 2, bucket_alloc);
APR_BRIGADE_INSERT_TAIL(req->header_brigade, e);
}
static int ap_proxy_http_prefetch(proxy_http_req_t *req,
apr_uri_t *uri, char *url)
{
apr_pool_t *p = req->p;
request_rec *r = req->r;
conn_rec *c = r->connection;
proxy_conn_rec *p_conn = req->backend;
apr_bucket_alloc_t *bucket_alloc = req->bucket_alloc;
apr_bucket_brigade *header_brigade = req->header_brigade;
apr_bucket_brigade *input_brigade = req->input_brigade;
apr_bucket *e;
apr_off_t bytes_read = 0;
apr_off_t bytes;
int rv;
rv = ap_proxy_create_hdrbrgd(p, header_brigade, r, p_conn,
req->worker, req->sconf,
uri, url, req->server_portstr,
&req->old_cl_val, &req->old_te_val);
if (rv != OK) {
return rv;
}
/* sub-requests never use keepalives, and mustn't pass request bodies.
* Because the new logic looks at input_brigade, we will self-terminate
* input_brigade and jump past all of the request body logic...
* Reading anything with ap_get_brigade is likely to consume the
* main request's body or read beyond EOS - which would be unpleasant.
*
* An exception: when a kept_body is present, then subrequest CAN use
* pass request bodies, and we DONT skip the body.
*/
if (!r->kept_body && r->main) {
/* XXX: Why DON'T sub-requests use keepalives? */
p_conn->close = 1;
req->old_te_val = NULL;
req->old_cl_val = NULL;
req->rb_method = RB_STREAM_CL;
e = apr_bucket_eos_create(input_brigade->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(input_brigade, e);
goto skip_body;
}
/* WE only understand chunked. Other modules might inject
* (and therefore, decode) other flavors but we don't know
* that the can and have done so unless they remove
* their decoding from the headers_in T-E list.
* XXX: Make this extensible, but in doing so, presume the
* encoding has been done by the extensions' handler, and
* do not modify add_te_chunked's logic
*/
if (req->old_te_val && ap_cstr_casecmp(req->old_te_val, "chunked") != 0) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01093)
"%s Transfer-Encoding is not supported",
req->old_te_val);
return HTTP_INTERNAL_SERVER_ERROR;
}
if (req->old_cl_val && req->old_te_val) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01094)
"client %s (%s) requested Transfer-Encoding "
"chunked body with Content-Length (C-L ignored)",
c->client_ip, c->remote_host ? c->remote_host: "");
req->old_cl_val = NULL;
p_conn->close = 1;
}
rv = ap_proxy_prefetch_input(r, req->backend, input_brigade,
req->prefetch_nonblocking ? APR_NONBLOCK_READ
: APR_BLOCK_READ,
&bytes_read, MAX_MEM_SPOOL);
if (rv != OK) {
return rv;
}
/* Use chunked request body encoding or send a content-length body?
*
* Prefer C-L when:
*
* We have no request body (handled by RB_STREAM_CL)
*
* We have a request body length <= MAX_MEM_SPOOL
*
* The administrator has setenv force-proxy-request-1.0
*
* The client sent a C-L body, and the administrator has
* not setenv proxy-sendchunked or has set setenv proxy-sendcl
*
* The client sent a T-E body, and the administrator has
* setenv proxy-sendcl, and not setenv proxy-sendchunked
*
* If both proxy-sendcl and proxy-sendchunked are set, the
* behavior is the same as if neither were set, large bodies
* that can't be read will be forwarded in their original
* form of C-L, or T-E.
*
* To ensure maximum compatibility, setenv proxy-sendcl
* To reduce server resource use, setenv proxy-sendchunked
*
* Then address specific servers with conditional setenv
* options to restore the default behavior where desirable.
*
* We have to compute content length by reading the entire request
* body; if request body is not small, we'll spool the remaining
* input to a temporary file. Chunked is always preferable.
*
* We can only trust the client-provided C-L if the T-E header
* is absent, and the filters are unchanged (the body won't
* be resized by another content filter).
*/
if (!APR_BRIGADE_EMPTY(input_brigade)
&& APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(input_brigade))) {
/* The whole thing fit, so our decision is trivial, use
* the filtered bytes read from the client for the request
* body Content-Length.
*
* If we expected no body, and read no body, do not set
* the Content-Length.
*/
if (req->old_cl_val || req->old_te_val || bytes_read) {
req->old_cl_val = apr_off_t_toa(r->pool, bytes_read);
req->cl_val = bytes_read;
}
req->rb_method = RB_STREAM_CL;
}
else if (req->old_te_val) {
if (req->force10
|| (apr_table_get(r->subprocess_env, "proxy-sendcl")
&& !apr_table_get(r->subprocess_env, "proxy-sendchunks")
&& !apr_table_get(r->subprocess_env, "proxy-sendchunked"))) {
req->rb_method = RB_SPOOL_CL;
}
else {
req->rb_method = RB_STREAM_CHUNKED;
}
}
else if (req->old_cl_val) {
if (r->input_filters == r->proto_input_filters) {
if (!ap_parse_strict_length(&req->cl_val, req->old_cl_val)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01085)
"could not parse request Content-Length (%s)",
req->old_cl_val);
return HTTP_BAD_REQUEST;
}
req->rb_method = RB_STREAM_CL;
}
else if (!req->force10
&& (apr_table_get(r->subprocess_env, "proxy-sendchunks")
|| apr_table_get(r->subprocess_env, "proxy-sendchunked"))
&& !apr_table_get(r->subprocess_env, "proxy-sendcl")) {
req->rb_method = RB_STREAM_CHUNKED;
}
else {
req->rb_method = RB_SPOOL_CL;
}
}
else {
/* This is an appropriate default; very efficient for no-body
* requests, and has the behavior that it will not add any C-L
* when the old_cl_val is NULL.
*/
req->rb_method = RB_SPOOL_CL;
}
switch (req->rb_method) {
case RB_STREAM_CHUNKED:
add_te_chunked(req->p, bucket_alloc, header_brigade);
break;
case RB_STREAM_CL:
if (req->old_cl_val) {
add_cl(req->p, bucket_alloc, header_brigade, req->old_cl_val);
}
break;
default: /* => RB_SPOOL_CL */
/* If we have to spool the body, do it now, before connecting or
* reusing the backend connection.
*/
rv = ap_proxy_spool_input(r, p_conn, input_brigade,
&bytes, MAX_MEM_SPOOL);
if (rv != OK) {
return rv;
}
if (bytes || req->old_te_val || req->old_cl_val) {
add_cl(p, bucket_alloc, header_brigade, apr_off_t_toa(p, bytes));
}
}
/* Yes I hate gotos. This is the subrequest shortcut */
skip_body:
terminate_headers(req);
return OK;
}
static int ap_proxy_http_request(proxy_http_req_t *req)
{
int rv;
request_rec *r = req->r;
/* send the request header/body, if any. */
switch (req->rb_method) {
case RB_SPOOL_CL:
case RB_STREAM_CL:
case RB_STREAM_CHUNKED:
if (req->do_100_continue) {
rv = ap_proxy_pass_brigade(req->bucket_alloc, r, req->backend,
req->origin, req->header_brigade, 1);
}
else {
rv = stream_reqbody(req);
}
break;
default:
/* shouldn't be possible */
rv = HTTP_INTERNAL_SERVER_ERROR;
break;
}
if (rv != OK) {
conn_rec *c = r->connection;
/* apr_status_t value has been logged in lower level method */
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01097)
"pass request body failed to %pI (%s) from %s (%s)",
req->backend->addr,
req->backend->hostname ? req->backend->hostname: "",
c->client_ip, c->remote_host ? c->remote_host: "");
return rv;
}
return OK;
}
/*
* If the date is a valid RFC 850 date or asctime() date, then it
* is converted to the RFC 1123 format.
*/
static const char *date_canon(apr_pool_t *p, const char *date)
{
apr_status_t rv;
char* ndate;
apr_time_t time = apr_date_parse_http(date);
if (!time) {
return date;
}
ndate = apr_palloc(p, APR_RFC822_DATE_LEN);
rv = apr_rfc822_date(ndate, time);
if (rv != APR_SUCCESS) {
return date;
}
return ndate;
}
static request_rec *make_fake_req(conn_rec *c, request_rec *r)
{
apr_pool_t *pool;
request_rec *rp;
apr_pool_create(&pool, c->pool);
apr_pool_tag(pool, "proxy_http_rp");
rp = apr_pcalloc(pool, sizeof(*r));
rp->pool = pool;
rp->status = HTTP_OK;
rp->headers_in = apr_table_make(pool, 50);
rp->trailers_in = apr_table_make(pool, 5);
rp->subprocess_env = apr_table_make(pool, 50);
rp->headers_out = apr_table_make(pool, 12);
rp->trailers_out = apr_table_make(pool, 5);
rp->err_headers_out = apr_table_make(pool, 5);
rp->notes = apr_table_make(pool, 5);
rp->server = r->server;
rp->log = r->log;
rp->proxyreq = r->proxyreq;
rp->request_time = r->request_time;
rp->connection = c;
rp->output_filters = c->output_filters;
rp->input_filters = c->input_filters;
rp->proto_output_filters = c->output_filters;
rp->proto_input_filters = c->input_filters;
rp->useragent_ip = c->client_ip;
rp->useragent_addr = c->client_addr;
rp->request_config = ap_create_request_config(pool);
proxy_run_create_req(r, rp);
return rp;
}
static void process_proxy_header(request_rec *r, proxy_dir_conf *c,
const char *key, const char *value)
{
static const char *date_hdrs[]
= { "Date", "Expires", "Last-Modified", NULL };
static const struct {
const char *name;
ap_proxy_header_reverse_map_fn func;
} transform_hdrs[] = {
{ "Location", ap_proxy_location_reverse_map },
{ "Content-Location", ap_proxy_location_reverse_map },
{ "URI", ap_proxy_location_reverse_map },
{ "Destination", ap_proxy_location_reverse_map },
{ "Set-Cookie", ap_proxy_cookie_reverse_map },
{ NULL, NULL }
};
int i;
for (i = 0; date_hdrs[i]; ++i) {
if (!ap_cstr_casecmp(date_hdrs[i], key)) {
apr_table_add(r->headers_out, key,
date_canon(r->pool, value));
return;
}
}
for (i = 0; transform_hdrs[i].name; ++i) {
if (!ap_cstr_casecmp(transform_hdrs[i].name, key)) {
apr_table_add(r->headers_out, key,
(*transform_hdrs[i].func)(r, c, value));
return;
}
}
apr_table_add(r->headers_out, key, value);
}
/*
* Note: pread_len is the length of the response that we've mistakenly
* read (assuming that we don't consider that an error via
* ProxyBadHeader StartBody). This depends on buffer actually being
* local storage to the calling code in order for pread_len to make
* any sense at all, since we depend on buffer still containing
* what was read by ap_getline() upon return.
*/
static apr_status_t ap_proxy_read_headers(request_rec *r, request_rec *rr,
char *buffer, int size,
conn_rec *c, int *pread_len)
{
int len;
char *value, *end;
int saw_headers = 0;
void *sconf = r->server->module_config;
proxy_server_conf *psc;
proxy_dir_conf *dconf;
apr_status_t rc;
apr_bucket_brigade *tmp_bb;
dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
psc = (proxy_server_conf *) ap_get_module_config(sconf, &proxy_module);
r->headers_out = apr_table_make(r->pool, 20);
r->trailers_out = apr_table_make(r->pool, 5);
*pread_len = 0;
/*
* Read header lines until we get the empty separator line, a read error,
* the connection closes (EOF), or we timeout.
*/
ap_log_rerror(APLOG_MARK, APLOG_TRACE4, 0, r,
"Headers received from backend:");
tmp_bb = apr_brigade_create(r->pool, c->bucket_alloc);
while (1) {
rc = ap_proxygetline(tmp_bb, buffer, size, rr,
AP_GETLINE_FOLD | AP_GETLINE_NOSPC_EOL, &len);
if (rc != APR_SUCCESS) {
if (APR_STATUS_IS_ENOSPC(rc)) {
int trunc = (len > 128 ? 128 : len) / 2;
ap_log_rerror(APLOG_MARK, APLOG_WARNING, rc, r, APLOGNO(10124)
"header size is over the limit allowed by "
"ResponseFieldSize (%d bytes). "
"Bad response header: '%.*s[...]%s'",
size, trunc, buffer, buffer + len - trunc);
}
else {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, rc, r, APLOGNO(10404)
"Error reading headers from backend");
}
r->headers_out = NULL;
return rc;
}
if (len <= 0) {
break;
}
else {
ap_log_rerror(APLOG_MARK, APLOG_TRACE4, 0, r, "%s", buffer);
}
if (!(value = strchr(buffer, ':'))) { /* Find the colon separator */
/* We may encounter invalid headers, usually from buggy
* MS IIS servers, so we need to determine just how to handle
* them. We can either ignore them, assume that they mark the
* start-of-body (eg: a missing CRLF) or (the default) mark
* the headers as totally bogus and return a 500. The sole
* exception is an extra "HTTP/1.0 200, OK" line sprinkled
* in between the usual MIME headers, which is a favorite
* IIS bug.
*/
/* XXX: The mask check is buggy if we ever see an HTTP/1.10 */
if (!apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
if (psc->badopt == bad_error) {
/* Nope, it wasn't even an extra HTTP header. Give up. */
r->headers_out = NULL;
return APR_EINVAL;
}
else if (psc->badopt == bad_body) {
/* if we've already started loading headers_out, then
* return what we've accumulated so far, in the hopes
* that they are useful; also note that we likely pre-read
* the first line of the response.
*/
if (saw_headers) {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01098)
"Starting body due to bogus non-header "
"in headers returned by %s (%s)",
r->uri, r->method);
*pread_len = len;
return APR_SUCCESS;
}
else {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01099)
"No HTTP headers returned by %s (%s)",
r->uri, r->method);
return APR_SUCCESS;
}
}
}
/* this is the psc->badopt == bad_ignore case */
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01100)
"Ignoring bogus HTTP header returned by %s (%s)",
r->uri, r->method);
continue;
}
*value = '\0';
++value;
/* XXX: RFC2068 defines only SP and HT as whitespace, this test is
* wrong... and so are many others probably.
*/
while (apr_isspace(*value))
++value; /* Skip to start of value */
/* should strip trailing whitespace as well */
for (end = &value[strlen(value)-1]; end > value && apr_isspace(*end); --end)
*end = '\0';
/* make sure we add so as not to destroy duplicated headers
* Modify headers requiring canonicalisation and/or affected
* by ProxyPassReverse and family with process_proxy_header
*/
process_proxy_header(r, dconf, buffer, value);
saw_headers = 1;
}
return APR_SUCCESS;
}
static int addit_dammit(void *v, const char *key, const char *val)
{
apr_table_addn(v, key, val);
return 1;
}
static apr_status_t ap_proxygetline(apr_bucket_brigade *bb, char *s, int n,
request_rec *r, int flags, int *read)
{
apr_status_t rv;
apr_size_t len;
rv = ap_rgetline(&s, n, &len, r, flags, bb);
apr_brigade_cleanup(bb);
if (rv == APR_SUCCESS || APR_STATUS_IS_ENOSPC(rv)) {
*read = (int)len;
} else {
*read = -1;
}
return rv;
}
/*
* Limit the number of interim responses we sent back to the client. Otherwise
* we suffer from a memory build up. Besides there is NO sense in sending back
* an unlimited number of interim responses to the client. Thus if we cross
* this limit send back a 502 (Bad Gateway).
*/
#ifndef AP_MAX_INTERIM_RESPONSES
#define AP_MAX_INTERIM_RESPONSES 10
#endif
static int add_trailers(void *data, const char *key, const char *val)
{
if (val) {
apr_table_add((apr_table_t*)data, key, val);
}
return 1;
}
static int send_continue_body(proxy_http_req_t *req)
{
int status;
/* Send the request body (fully). */
switch(req->rb_method) {
case RB_SPOOL_CL:
case RB_STREAM_CL:
case RB_STREAM_CHUNKED:
status = stream_reqbody(req);
break;
default:
/* Shouldn't happen */
status = HTTP_INTERNAL_SERVER_ERROR;
break;
}
if (status != OK) {
conn_rec *c = req->r->connection;
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, req->r,
APLOGNO(10154) "pass request body failed "
"to %pI (%s) from %s (%s) with status %i",
req->backend->addr,
req->backend->hostname ? req->backend->hostname : "",
c->client_ip, c->remote_host ? c->remote_host : "",
status);
req->backend->close = 1;
}
return status;
}
static
int ap_proxy_http_process_response(proxy_http_req_t *req)
{
apr_pool_t *p = req->p;
request_rec *r = req->r;
conn_rec *c = r->connection;
proxy_worker *worker = req->worker;
proxy_conn_rec *backend = req->backend;
conn_rec *origin = req->origin;
int do_100_continue = req->do_100_continue;
int status;
char *buffer;
char fixed_buffer[HUGE_STRING_LEN];
const char *buf;
char keepchar;
apr_bucket *e;
apr_bucket_brigade *bb;
apr_bucket_brigade *pass_bb;
int len, backasswards;
int interim_response = 0; /* non-zero whilst interim 1xx responses
* are being read. */
apr_size_t response_field_size = 0;
int pread_len = 0;
apr_table_t *save_table;
int backend_broke = 0;
static const char *hop_by_hop_hdrs[] =
{"Keep-Alive", "Proxy-Authenticate", "TE", "Trailer", "Upgrade", NULL};
int i;
const char *te = NULL;
int original_status = r->status;
int proxy_status = OK;
const char *original_status_line = r->status_line;
const char *proxy_status_line = NULL;
apr_interval_time_t old_timeout = 0;
proxy_dir_conf *dconf;
dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
bb = apr_brigade_create(p, c->bucket_alloc);
pass_bb = apr_brigade_create(p, c->bucket_alloc);
/* Only use dynamically sized buffer if user specifies ResponseFieldSize */
if(backend->worker->s->response_field_size_set) {
response_field_size = backend->worker->s->response_field_size;
if (response_field_size != HUGE_STRING_LEN)
buffer = apr_pcalloc(p, response_field_size);
else
buffer = fixed_buffer;
}
else {
response_field_size = HUGE_STRING_LEN;
buffer = fixed_buffer;
}
/* Setup for 100-Continue timeout if appropriate */
if (do_100_continue && worker->s->ping_timeout_set) {
apr_socket_timeout_get(backend->sock, &old_timeout);
if (worker->s->ping_timeout != old_timeout) {
apr_status_t rc;
rc = apr_socket_timeout_set(backend->sock, worker->s->ping_timeout);
if (rc != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(01101)
"could not set 100-Continue timeout");
}
}
}
/* Get response from the remote server, and pass it up the
* filter chain
*/
backend->r = make_fake_req(origin, r);
/* In case anyone needs to know, this is a fake request that is really a
* response.
*/
backend->r->proxyreq = PROXYREQ_RESPONSE;
apr_table_setn(r->notes, "proxy-source-port", apr_psprintf(r->pool, "%hu",
origin->local_addr->port));
do {
apr_status_t rc;
const char *upgrade = NULL;
int major = 0, minor = 0;
int toclose = 0;
apr_brigade_cleanup(bb);
rc = ap_proxygetline(backend->tmp_bb, buffer, response_field_size,
backend->r, 0, &len);
if (len == 0) {
/* handle one potential stray CRLF */
rc = ap_proxygetline(backend->tmp_bb, buffer, response_field_size,
backend->r, 0, &len);
}
if (len <= 0) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(01102)
"error reading status line from remote "
"server %s:%d", backend->hostname, backend->port);
if (APR_STATUS_IS_TIMEUP(rc)) {
apr_table_setn(r->notes, "proxy_timedout", "1");
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01103) "read timeout");
if (do_100_continue) {
return ap_proxyerror(r, HTTP_SERVICE_UNAVAILABLE,
"Timeout on 100-Continue");
}
}
/*
* If we are a reverse proxy request shutdown the connection
* WITHOUT ANY response to trigger a retry by the client
* if allowed (as for idempotent requests).
* BUT currently we should not do this if the request is the
* first request on a keepalive connection as browsers like
* seamonkey only display an empty page in this case and do
* not do a retry. We should also not do this on a
* connection which times out; instead handle as
* we normally would handle timeouts
*/
if (r->proxyreq == PROXYREQ_REVERSE && c->keepalives &&
!APR_STATUS_IS_TIMEUP(rc)) {
apr_bucket *eos;
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01104)
"Closing connection to client because"
" reading from backend server %s:%d failed."
" Number of keepalives %i", backend->hostname,
backend->port, c->keepalives);
ap_proxy_backend_broke(r, bb);
/*
* Add an EOC bucket to signal the ap_http_header_filter
* that it should get out of our way, BUT ensure that the
* EOC bucket is inserted BEFORE an EOS bucket in bb as
* some resource filters like mod_deflate pass everything
* up to the EOS down the chain immediately and sent the
* remainder of the brigade later (or even never). But in
* this case the ap_http_header_filter does not get out of
* our way soon enough.
*/
e = ap_bucket_eoc_create(c->bucket_alloc);
eos = APR_BRIGADE_LAST(bb);
while ((APR_BRIGADE_SENTINEL(bb) != eos)
&& !APR_BUCKET_IS_EOS(eos)) {
eos = APR_BUCKET_PREV(eos);
}
if (eos == APR_BRIGADE_SENTINEL(bb)) {
APR_BRIGADE_INSERT_TAIL(bb, e);
}
else {
APR_BUCKET_INSERT_BEFORE(eos, e);
}
ap_pass_brigade(r->output_filters, bb);
/* Mark the backend connection for closing */
backend->close = 1;
if (origin->keepalives) {
/* We already had a request on this backend connection and
* might just have run into a keepalive race. Hence we
* think positive and assume that the backend is fine and
* we do not need to signal an error on backend side.
*/
return OK;
}
/*
* This happened on our first request on this connection to the
* backend. This indicates something fishy with the backend.
* Return HTTP_INTERNAL_SERVER_ERROR to signal an unrecoverable
* server error. We do not worry about r->status code and a
* possible error response here as the ap_http_outerror_filter
* will fix all of this for us.
*/
return HTTP_INTERNAL_SERVER_ERROR;
}
if (!c->keepalives) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01105)
"NOT Closing connection to client"
" although reading from backend server %s:%d"
" failed.",
backend->hostname, backend->port);
}
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
"Error reading from remote server");
}
/* XXX: Is this a real headers length send from remote? */
backend->worker->s->read += len;
/* Is it an HTTP/1 response?
* This is buggy if we ever see an HTTP/1.10
*/
if (apr_date_checkmask(buffer, "HTTP/#.# ###*")) {
major = buffer[5] - '0';
minor = buffer[7] - '0';
/* If not an HTTP/1 message or
* if the status line was > 8192 bytes
*/
if ((major != 1) || (len >= response_field_size - 1)) {
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
apr_pstrcat(p, "Corrupt status line returned "
"by remote server: ", buffer, NULL));
}
backasswards = 0;
keepchar = buffer[12];
buffer[12] = '\0';
proxy_status = atoi(&buffer[9]);
apr_table_setn(r->notes, "proxy-status",
apr_pstrdup(r->pool, &buffer[9]));
if (keepchar != '\0') {
buffer[12] = keepchar;
} else {
/* 2616 requires the space in Status-Line; the origin
* server may have sent one but ap_rgetline_core will
* have stripped it. */
buffer[12] = ' ';
buffer[13] = '\0';
}
proxy_status_line = apr_pstrdup(p, &buffer[9]);
/* The status out of the front is the same as the status coming in
* from the back, until further notice.
*/
r->status = proxy_status;
r->status_line = proxy_status_line;
ap_log_rerror(APLOG_MARK, APLOG_TRACE3, 0, r,
"Status from backend: %d", proxy_status);
/* read the headers. */
/* N.B. for HTTP/1.0 clients, we have to fold line-wrapped headers*/
/* Also, take care with headers with multiple occurrences. */
/* First, tuck away all already existing cookies */
save_table = apr_table_make(r->pool, 2);
apr_table_do(addit_dammit, save_table, r->headers_out,
"Set-Cookie", NULL);
/* shove the headers direct into r->headers_out */
rc = ap_proxy_read_headers(r, backend->r, buffer, response_field_size,
origin, &pread_len);
if (rc != APR_SUCCESS || r->headers_out == NULL) {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01106)
"bad HTTP/%d.%d header returned by %s (%s)",
major, minor, r->uri, r->method);
backend->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;
}
/* Now, add in the just read cookies */
apr_table_do(addit_dammit, save_table, r->headers_out,
"Set-Cookie", NULL);
/* and now load 'em all in */
if (!apr_is_empty_table(save_table)) {
apr_table_unset(r->headers_out, "Set-Cookie");
r->headers_out = apr_table_overlay(r->pool,
r->headers_out,
save_table);
}
/*
* Save a possible Transfer-Encoding header as we need it later for
* ap_http_filter to know where to end.
*/
te = apr_table_get(r->headers_out, "Transfer-Encoding");
/* can't have both Content-Length and Transfer-Encoding */
if (te && apr_table_get(r->headers_out, "Content-Length")) {
/*
* 2616 section 4.4, point 3: "if both Transfer-Encoding
* and Content-Length are received, the latter MUST be
* ignored";
*
* To help mitigate HTTP Splitting, unset Content-Length
* and shut down the backend server connection
* XXX: We aught to treat such a response as uncachable
*/
apr_table_unset(r->headers_out, "Content-Length");
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01107)
"server %s:%d returned Transfer-Encoding"
" and Content-Length",
backend->hostname, backend->port);
backend->close = 1;
}
upgrade = apr_table_get(r->headers_out, "Upgrade");
if (proxy_status == HTTP_SWITCHING_PROTOCOLS) {
if (!upgrade || !req->upgrade || (strcasecmp(req->upgrade,
upgrade) != 0)) {
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
apr_pstrcat(p, "Unexpected Upgrade: ",
upgrade ? upgrade : "n/a",
" (expecting ",
req->upgrade ? req->upgrade
: "n/a", ")",
NULL));
}
backend->close = 1;
}
/* strip connection listed hop-by-hop headers from response */
toclose = ap_proxy_clear_connection_fn(r, r->headers_out);
if (toclose) {
backend->close = 1;
if (toclose < 0) {
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
"Malformed connection header");
}
}
if ((buf = apr_table_get(r->headers_out, "Content-Type"))) {
ap_set_content_type(r, apr_pstrdup(p, buf));
}
if (!ap_is_HTTP_INFO(proxy_status)) {
ap_proxy_pre_http_request(origin, backend->r);
}
/* Clear hop-by-hop headers */
for (i=0; hop_by_hop_hdrs[i]; ++i) {
apr_table_unset(r->headers_out, hop_by_hop_hdrs[i]);
}
/* Delete warnings with wrong date */
r->headers_out = ap_proxy_clean_warnings(p, r->headers_out);
/* handle Via header in response */
if (req->sconf->viaopt != via_off
&& req->sconf->viaopt != via_block) {
const char *server_name = ap_get_server_name(r);
/* If USE_CANONICAL_NAME_OFF was configured for the proxy virtual host,
* then the server name returned by ap_get_server_name() is the
* origin server name (which does make too much sense with Via: headers)
* so we use the proxy vhost's name instead.
*/
if (server_name == r->hostname)
server_name = r->server->server_hostname;
/* create a "Via:" response header entry and merge it */
apr_table_addn(r->headers_out, "Via",
(req->sconf->viaopt == via_full)
? apr_psprintf(p, "%d.%d %s%s (%s)",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
server_name,
req->server_portstr,
AP_SERVER_BASEVERSION)
: apr_psprintf(p, "%d.%d %s%s",
HTTP_VERSION_MAJOR(r->proto_num),
HTTP_VERSION_MINOR(r->proto_num),
server_name,
req->server_portstr)
);
}
/* cancel keepalive if HTTP/1.0 or less */
if ((major < 1) || (minor < 1)) {
backend->close = 1;
origin->keepalive = AP_CONN_CLOSE;
}
else {
/*
* Keep track of the number of keepalives we processed on this
* connection.
*/
origin->keepalives++;
}
} else {
/* an http/0.9 response */
backasswards = 1;
r->status = proxy_status = 200;
r->status_line = "200 OK";
backend->close = 1;
}
if (ap_is_HTTP_INFO(proxy_status)) {
const char *policy = NULL;
/* RFC2616 tells us to forward this.
*
* OTOH, an interim response here may mean the backend
* is playing sillybuggers. The Client didn't ask for
* it within the defined HTTP/1.1 mechanisms, and if
* it's an extension, it may also be unsupported by us.
*
* There's also the possibility that changing existing
* behaviour here might break something.
*
* So let's make it configurable.
*
* We need to force "r->expecting_100 = 1" for RFC behaviour
* otherwise ap_send_interim_response() does nothing when
* the client did not ask for 100-continue.
*
* 101 Switching Protocol has its own configuration which
* shouldn't be interfered by "proxy-interim-response".
*/
if (proxy_status != HTTP_SWITCHING_PROTOCOLS) {
policy = apr_table_get(r->subprocess_env,
"proxy-interim-response");
}
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
"HTTP: received interim %d response (policy: %s)",
r->status, policy ? policy : "n/a");
if (!policy
|| (!strcasecmp(policy, "RFC")
&& (proxy_status != HTTP_CONTINUE
|| (r->expecting_100 = 1)))) {
switch (proxy_status) {
case HTTP_SWITCHING_PROTOCOLS:
AP_DEBUG_ASSERT(upgrade != NULL);
apr_table_setn(r->headers_out, "Connection", "Upgrade");
apr_table_setn(r->headers_out, "Upgrade",
apr_pstrdup(p, upgrade));
break;
}
ap_send_interim_response(r, 1);
}
/* FIXME: refine this to be able to specify per-response-status
* policies and maybe also add option to bail out with 502
*/
else if (strcasecmp(policy, "Suppress")) {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01108)
"undefined proxy interim response policy");
}
interim_response++;
}
else {
interim_response = 0;
}
/* If we still do 100-continue (end-to-end or ping), either the
* current response is the expected "100 Continue" and we are done
* with this mode, or this is another interim response and we'll wait
* for the next one, or this is a final response and hence the backend
* did not honor our expectation.
*/
if (do_100_continue && (!interim_response
|| proxy_status == HTTP_CONTINUE)) {
/* RFC 7231 - Section 5.1.1 - Expect - Requirement for servers
* A server that responds with a final status code before
* reading the entire message body SHOULD indicate in that
* response whether it intends to close the connection or
* continue reading and discarding the request message.
*
* So, if this response is not an interim 100 Continue, we can
* avoid sending the request body if the backend responded with
* "Connection: close" or HTTP < 1.1, and either let the core
* discard it or the caller try another balancer member with the
* same body (given status 503, though not implemented yet).
*/
int do_send_body = (proxy_status == HTTP_CONTINUE
|| (!toclose && major > 0 && minor > 0));
/* Reset to old timeout iff we've adjusted it. */
if (worker->s->ping_timeout_set) {
apr_socket_timeout_set(backend->sock, old_timeout);
}
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(10153)
"HTTP: %s100 continue sent by %pI (%s): "
"%ssending body (response: HTTP/%i.%i %s)",
proxy_status != HTTP_CONTINUE ? "no " : "",
backend->addr,
backend->hostname ? backend->hostname : "",
do_send_body ? "" : "not ",
major, minor, proxy_status_line);
if (do_send_body) {
status = send_continue_body(req);
if (status != OK) {
return status;
}
}
else {
/* If we don't read the client connection any further, since
* there are pending data it should be "Connection: close"d to
* prevent reuse. We don't exactly c->keepalive = AP_CONN_CLOSE
* here though, because error_override or a potential retry on
* another backend could finally read that data and finalize
* the request processing, making keep-alive possible. So what
* we do is leaving r->expecting_100 alone, ap_set_keepalive()
* will do the right thing according to the final response and
* any later update of r->expecting_100.
*/
}
/* Once only! */
do_100_continue = 0;
}
if (proxy_status == HTTP_SWITCHING_PROTOCOLS) {
apr_status_t rv;
proxy_tunnel_rec *tunnel;
apr_interval_time_t client_timeout = -1,
backend_timeout = -1;
/* If we didn't send the full body yet, do it now */
if (do_100_continue) {
r->expecting_100 = 0;
status = send_continue_body(req);
if (status != OK) {
return status;
}
}
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(10239)
"HTTP: tunneling protocol %s", upgrade);
rv = ap_proxy_tunnel_create(&tunnel, r, origin, upgrade);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(10240)
"can't create tunnel for %s", upgrade);
return HTTP_INTERNAL_SERVER_ERROR;
}
/* Set timeout to the highest configured for client or backend */
apr_socket_timeout_get(backend->sock, &backend_timeout);
apr_socket_timeout_get(ap_get_conn_socket(c), &client_timeout);
if (backend_timeout >= 0 && backend_timeout > client_timeout) {
tunnel->timeout = backend_timeout;
}
else {
tunnel->timeout = client_timeout;
}
/* Let proxy tunnel forward everything */
status = ap_proxy_tunnel_run(tunnel);
/* We are done with both connections */
return DONE;
}
if (interim_response) {
/* Already forwarded above, read next response */
continue;
}
/* Moved the fixups of Date headers and those affected by
* ProxyPassReverse/etc from here to ap_proxy_read_headers
*/
/* PR 41646: get HEAD right with ProxyErrorOverride */
if (ap_proxy_should_override(dconf, proxy_status)) {
if (proxy_status == HTTP_UNAUTHORIZED) {
const char *buf;
const char *wa = "WWW-Authenticate";
if ((buf = apr_table_get(r->headers_out, wa))) {
apr_table_set(r->err_headers_out, wa, buf);
} else {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01109)
"origin server sent 401 without "
"WWW-Authenticate header");
}
}
/* clear r->status for override error, otherwise ErrorDocument
* thinks that this is a recursive error, and doesn't find the
* custom error page
*/
r->status = HTTP_OK;
/* Discard body, if one is expected */
if (!r->header_only && !AP_STATUS_IS_HEADER_ONLY(proxy_status)) {
const char *tmp;
/* Add minimal headers needed to allow http_in filter
* detecting end of body without waiting for a timeout. */
if ((tmp = apr_table_get(r->headers_out, "Transfer-Encoding"))) {
apr_table_set(backend->r->headers_in, "Transfer-Encoding", tmp);
}
else if ((tmp = apr_table_get(r->headers_out, "Content-Length"))) {
apr_table_set(backend->r->headers_in, "Content-Length", tmp);
}
else if (te) {
apr_table_set(backend->r->headers_in, "Transfer-Encoding", te);
}
ap_discard_request_body(backend->r);
}
/*
* prevent proxy_handler() from treating this as an
* internal error.
*/
apr_table_setn(r->notes, "proxy-error-override", "1");
return proxy_status;
}
/* Forward back Upgrade header if it matches the configured one(s), it
* may be an HTTP_UPGRADE_REQUIRED response or some other status where
* Upgrade makes sense to negotiate the protocol by other means.
*/
if (upgrade && ap_proxy_worker_can_upgrade(p, worker, upgrade,
(*req->proto == 'w')
? "WebSocket" : NULL)) {
apr_table_setn(r->headers_out, "Connection", "Upgrade");
apr_table_setn(r->headers_out, "Upgrade", apr_pstrdup(p, upgrade));
}
r->sent_bodyct = 1;
/*
* Is it an HTTP/0.9 response or did we maybe preread the 1st line of
* the response? If so, load the extra data. These are 2 mutually
* exclusive possibilities, that just happen to require very
* similar behavior.
*/
if (backasswards || pread_len) {
apr_ssize_t cntr = (apr_ssize_t)pread_len;
if (backasswards) {
/*@@@FIXME:
* At this point in response processing of a 0.9 response,
* we don't know yet whether data is binary or not.
* mod_charset_lite will get control later on, so it cannot
* decide on the conversion of this buffer full of data.
* However, chances are that we are not really talking to an
* HTTP/0.9 server, but to some different protocol, therefore
* the best guess IMHO is to always treat the buffer as "text/x":
*/
ap_xlate_proto_to_ascii(buffer, len);
cntr = (apr_ssize_t)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 */
(proxy_status != HTTP_NO_CONTENT) && /* not 204 */
(proxy_status != HTTP_NOT_MODIFIED)) { /* not 304 */
apr_read_type_e mode;
int finish;
/* 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, so that they are preserved accordingly for
* ap_http_filter to know where to end.
*/
backend->r->headers_in = apr_table_clone(backend->r->pool, r->headers_out);
/*
* Restore Transfer-Encoding header from response if we saved
* one before and there is none left. We need it for the
* ap_http_filter. See above.
*/
if (te && !apr_table_get(backend->r->headers_in, "Transfer-Encoding")) {
apr_table_add(backend->r->headers_in, "Transfer-Encoding", te);
}
apr_table_unset(r->headers_out,"Transfer-Encoding");
ap_log_rerror(APLOG_MARK, APLOG_TRACE3, 0, r, "start body send");
/* read the body, pass it to the output filters */
/* Handle the case where the error document is itself reverse
* proxied and was successful. We must maintain any previous
* error status so that an underlying error (eg HTTP_NOT_FOUND)
* doesn't become an HTTP_OK.
*/
if (ap_proxy_should_override(dconf, original_status)) {
r->status = original_status;
r->status_line = original_status_line;
}
mode = APR_NONBLOCK_READ;
finish = FALSE;
do {
apr_off_t readbytes;
apr_status_t rv;
rv = ap_get_brigade(backend->r->input_filters, bb,
AP_MODE_READBYTES, mode,
req->sconf->io_buffer_size);
/* ap_get_brigade will return success with an empty brigade
* for a non-blocking read which would block: */
if (mode == APR_NONBLOCK_READ
&& (APR_STATUS_IS_EAGAIN(rv)
|| (rv == APR_SUCCESS && APR_BRIGADE_EMPTY(bb)))) {
/* flush to the client and switch to blocking mode */
e = apr_bucket_flush_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
if (ap_pass_brigade(r->output_filters, bb)
|| c->aborted) {
backend->close = 1;
break;
}
apr_brigade_cleanup(bb);
mode = APR_BLOCK_READ;
continue;
}
else if (rv == APR_EOF) {
backend->close = 1;
break;
}
else if (rv != APR_SUCCESS) {
/* In this case, we are in real trouble because
* our backend bailed on us. Pass along a 502 error
* error bucket
*/
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01110)
"error reading response");
apr_brigade_cleanup(bb);
ap_proxy_backend_broke(r, bb);
ap_pass_brigade(r->output_filters, bb);
backend_broke = 1;
backend->close = 1;
break;
}
/* next time try a non-blocking read */
mode = APR_NONBLOCK_READ;
if (!apr_is_empty_table(backend->r->trailers_in)) {
apr_table_do(add_trailers, r->trailers_out,
backend->r->trailers_in, NULL);
apr_table_clear(backend->r->trailers_in);
}
apr_brigade_length(bb, 0, &readbytes);
backend->worker->s->read += readbytes;
#if DEBUGGING
{
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01111)
"readbytes: %#x", readbytes);
}
#endif
/* sanity check */
if (APR_BRIGADE_EMPTY(bb)) {
break;
}
/* Switch the allocator lifetime of the buckets */
ap_proxy_buckets_lifetime_transform(r, bb, pass_bb);
/* found the last brigade? */
if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(pass_bb))) {
/* signal that we must leave */
finish = TRUE;
/* the brigade may contain transient buckets that contain
* data that lives only as long as the backend connection.
* Force a setaside so these transient buckets become heap
* buckets that live as long as the request.
*/
for (e = APR_BRIGADE_FIRST(pass_bb); e
!= APR_BRIGADE_SENTINEL(pass_bb); e
= APR_BUCKET_NEXT(e)) {
apr_bucket_setaside(e, r->pool);
}
/* finally it is safe to clean up the brigade from the
* connection pool, as we have forced a setaside on all
* buckets.
*/
apr_brigade_cleanup(bb);
/* make sure we release the backend connection as soon
* as we know we are done, so that the backend isn't
* left waiting for a slow client to eventually
* acknowledge the data.
*/
ap_proxy_release_connection(backend->worker->s->scheme,
backend, r->server);
/* Ensure that the backend is not reused */
req->backend = NULL;
}
/* try send what we read */
if (ap_pass_brigade(r->output_filters, pass_bb) != APR_SUCCESS
|| c->aborted) {
/* Ack! Phbtt! Die! User aborted! */
/* Only close backend if we haven't got all from the
* backend. Furthermore if req->backend is NULL it is no
* longer safe to fiddle around with backend as it might
* be already in use by another thread.
*/
if (req->backend) {
/* this causes socket close below */
req->backend->close = 1;
}
finish = TRUE;
}
/* make sure we always clean up after ourselves */
apr_brigade_cleanup(pass_bb);
apr_brigade_cleanup(bb);
} while (!finish);
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "end body send");
}
else {
ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "header only");
/* make sure we release the backend connection as soon
* as we know we are done, so that the backend isn't
* left waiting for a slow client to eventually
* acknowledge the data.
*/
ap_proxy_release_connection(backend->worker->s->scheme,
backend, r->server);
/* Ensure that the backend is not reused */
req->backend = NULL;
/* Pass EOS bucket down the filter chain. */
e = apr_bucket_eos_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, e);
ap_pass_brigade(r->output_filters, bb);
apr_brigade_cleanup(bb);
}
} while (interim_response && (interim_response < AP_MAX_INTERIM_RESPONSES));
/* We have to cleanup bb brigade, because buckets inserted to it could be
* created from scpool and this pool can be freed before this brigade. */
apr_brigade_cleanup(bb);
/* See define of AP_MAX_INTERIM_RESPONSES for why */
if (interim_response >= AP_MAX_INTERIM_RESPONSES) {
return ap_proxyerror(r, HTTP_BAD_GATEWAY,
apr_psprintf(p,
"Too many (%d) interim responses from origin server",
interim_response));
}
/* If our connection with the client is to be aborted, return DONE. */
if (c->aborted || backend_broke) {
return DONE;
}
return OK;
}
static
apr_status_t ap_proxy_http_cleanup(const char *scheme, request_rec *r,
proxy_conn_rec *backend)
{
ap_proxy_release_connection(scheme, backend, r->server);
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.)
*/
static int proxy_http_handler(request_rec *r, proxy_worker *worker,
proxy_server_conf *conf,
char *url, const char *proxyname,
apr_port_t proxyport)
{
int status;
const char *scheme;
const char *u = url;
proxy_http_req_t *req = NULL;
proxy_conn_rec *backend = NULL;
apr_bucket_brigade *input_brigade = NULL;
int is_ssl = 0;
conn_rec *c = r->connection;
proxy_dir_conf *dconf;
int retry = 0;
char *locurl = url;
int toclose = 0;
/*
* Use a shorter-lived pool to reduce memory usage
* and avoid a memory leak
*/
apr_pool_t *p = r->pool;
apr_uri_t *uri;
scheme = get_url_scheme(&u, &is_ssl);
if (!scheme && proxyname && strncasecmp(url, "ftp:", 4) == 0) {
u = url + 4;
scheme = "ftp";
is_ssl = 0;
}
if (!scheme || u[0] != '/' || u[1] != '/' || u[2] == '\0') {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01113)
"HTTP: declining URL %s", url);
return DECLINED; /* only interested in HTTP, WS or FTP via proxy */
}
if (is_ssl && !ap_ssl_has_outgoing_handlers()) {
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01112)
"HTTP: declining URL %s (mod_ssl not configured?)", url);
return DECLINED;
}
ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r, "HTTP: serving URL %s", url);
/* create space for state information */
if ((status = ap_proxy_acquire_connection(scheme, &backend,
worker, r->server)) != OK) {
return status;
}
backend->is_ssl = is_ssl;
req = apr_pcalloc(p, sizeof(*req));
req->p = p;
req->r = r;
req->sconf = conf;
req->worker = worker;
req->backend = backend;
req->proto = scheme;
req->bucket_alloc = c->bucket_alloc;
req->rb_method = RB_INIT;
dconf = ap_get_module_config(r->per_dir_config, &proxy_module);
if (apr_table_get(r->subprocess_env, "force-proxy-request-1.0")) {
req->force10 = 1;
}
else if (*worker->s->upgrade || *req->proto == 'w') {
/* Forward Upgrade header if it matches the configured one(s),
* the default being "WebSocket" for ws[s] schemes.
*/
const char *upgrade = apr_table_get(r->headers_in, "Upgrade");
if (upgrade && ap_proxy_worker_can_upgrade(p, worker, upgrade,
(*req->proto == 'w')
? "WebSocket" : NULL)) {
req->upgrade = upgrade;
}
}
/* We possibly reuse input data prefetched in previous call(s), e.g. for a
* balancer fallback scenario, and in this case the 100 continue settings
* should be consistent between balancer members. If not, we need to ignore
* Proxy100Continue on=>off once we tried to prefetch already, otherwise
* the HTTP_IN filter won't send 100 Continue for us anymore, and we might
* deadlock with the client waiting for each other. Note that off=>on is
* not an issue because in this case r->expecting_100 is false (the 100
* Continue is out already), but we make sure that prefetch will be
* nonblocking to avoid passing more time there.
*/
apr_pool_userdata_get((void **)&input_brigade, "proxy-req-input", p);
/* Should we handle end-to-end or ping 100-continue? */
if (!req->force10
&& ((r->expecting_100 && (dconf->forward_100_continue || input_brigade))
|| PROXY_SHOULD_PING_100_CONTINUE(worker, r))) {
/* Tell ap_proxy_create_hdrbrgd() to preserve/add the Expect header */
apr_table_setn(r->notes, "proxy-100-continue", "1");
req->do_100_continue = 1;
}
/* Should we block while prefetching the body or try nonblocking and flush
* data to the backend ASAP?
*/
if (input_brigade
|| req->do_100_continue
|| apr_table_get(r->subprocess_env,
"proxy-prefetch-nonblocking")) {
req->prefetch_nonblocking = 1;
}
/*
* In the case that we are handling a reverse proxy connection and this
* is not a request that is coming over an already kept alive connection
* with the client, do NOT reuse the connection to the backend, because
* we cannot forward a failure to the client in this case as the client
* does NOT expect this in this situation.
* Yes, this creates a performance penalty.
*/
if ((r->proxyreq == PROXYREQ_REVERSE) && (!c->keepalives)
&& (apr_table_get(r->subprocess_env, "proxy-initial-not-pooled"))) {
backend->close = 1;
}
/* Step One: Determine Who To Connect To */
uri = apr_palloc(p, sizeof(*uri));
if ((status = ap_proxy_determine_connection(p, r, conf, worker, backend,
uri, &locurl, proxyname,
proxyport, req->server_portstr,
sizeof(req->server_portstr))))
goto cleanup;
/* The header is always (re-)built since it depends on worker settings,
* but the body can be fetched only once (even partially), so it's saved
* in between proxy_http_handler() calls should we come back here.
*/
req->header_brigade = apr_brigade_create(p, req->bucket_alloc);
if (input_brigade == NULL) {
input_brigade = apr_brigade_create(p, req->bucket_alloc);
apr_pool_userdata_setn(input_brigade, "proxy-req-input", NULL, p);
}
req->input_brigade = input_brigade;
/* Prefetch (nonlocking) the request body so to increase the chance to get
* the whole (or enough) body and determine Content-Length vs chunked or
* spooled. By doing this before connecting or reusing the backend, we want
* to minimize the delay between this connection is considered alive and
* the first bytes sent (should the client's link be slow or some input
* filter retain the data). This is a best effort to prevent the backend
* from closing (from under us) what it thinks is an idle connection, hence
* to reduce to the minimum the unavoidable local is_socket_connected() vs
* remote keepalive race condition.
*/
if ((status = ap_proxy_http_prefetch(req, uri, locurl)) != OK)
goto cleanup;
/* We need to reset backend->close now, since ap_proxy_http_prefetch() set
* it to disable the reuse of the connection *after* this request (no keep-
* alive), not to close any reusable connection before this request. However
* assure what is expected later by using a local flag and do the right thing
* when ap_proxy_connect_backend() below provides the connection to close.
*/
toclose = backend->close;
backend->close = 0;
while (retry < 2) {
if (retry) {
char *newurl = url;
/* Step One (again): (Re)Determine Who To Connect To */
if ((status = ap_proxy_determine_connection(p, r, conf, worker,
backend, uri, &newurl, proxyname, proxyport,
req->server_portstr, sizeof(req->server_portstr))))
break;
/* The code assumes locurl is not changed during the loop, or
* ap_proxy_http_prefetch() would have to be called every time,
* and header_brigade be changed accordingly...
*/
AP_DEBUG_ASSERT(strcmp(newurl, locurl) == 0);
}
/* Step Two: Make the Connection */
if (ap_proxy_check_connection(scheme, backend, r->server, 1,
PROXY_CHECK_CONN_EMPTY)
&& ap_proxy_connect_backend(scheme, backend, worker,
r->server)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01114)
"HTTP: failed to make connection to backend: %s",
backend->hostname);
status = HTTP_SERVICE_UNAVAILABLE;
break;
}
/* Step Three: Create conn_rec */
if ((status = ap_proxy_connection_create_ex(scheme, backend, r)) != OK)
break;
req->origin = backend->connection;
/* Don't recycle the connection if prefetch (above) told not to do so */
if (toclose) {
backend->close = 1;
req->origin->keepalive = AP_CONN_CLOSE;
}
/* Step Four: Send the Request
* On the off-chance that we forced a 100-Continue as a
* kinda HTTP ping test, allow for retries
*/
status = ap_proxy_http_request(req);
if (status != OK) {
if (req->do_100_continue && status == HTTP_SERVICE_UNAVAILABLE) {
ap_log_rerror(APLOG_MARK, APLOG_INFO, status, r, APLOGNO(01115)
"HTTP: 100-Continue failed to %pI (%s:%d)",
backend->addr, backend->hostname, backend->port);
backend->close = 1;
retry++;
continue;
}
break;
}
/* Step Five: Receive the Response... Fall thru to cleanup */
status = ap_proxy_http_process_response(req);
break;
}
/* Step Six: Clean Up */
cleanup:
if (req->backend) {
if (status != OK)
req->backend->close = 1;
ap_proxy_http_cleanup(scheme, r, req->backend);
}
return status;
}
/* post_config hook: */
static int proxy_http_post_config(apr_pool_t *pconf, apr_pool_t *plog,
apr_pool_t *ptemp, server_rec *s)
{
/* proxy_http_post_config() will be called twice during startup. So, don't
* set up the static data the 1st time through. */
if (ap_state_query(AP_SQ_MAIN_STATE) == AP_SQ_MS_CREATE_PRE_CONFIG) {
return OK;
}
ap_proxy_clear_connection_fn =
APR_RETRIEVE_OPTIONAL_FN(ap_proxy_clear_connection);
if (!ap_proxy_clear_connection_fn) {
ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s, APLOGNO(02477)
"mod_proxy must be loaded for mod_proxy_http");
return !OK;
}
return OK;
}
static void ap_proxy_http_register_hook(apr_pool_t *p)
{
ap_hook_post_config(proxy_http_post_config, NULL, NULL, APR_HOOK_MIDDLE);
proxy_hook_scheme_handler(proxy_http_handler, NULL, NULL, APR_HOOK_FIRST);
proxy_hook_canon_handler(proxy_http_canon, NULL, NULL, APR_HOOK_FIRST);
warn_rx = ap_pregcomp(p, "[0-9]{3}[ \t]+[^ \t]+[ \t]+\"[^\"]*\"([ \t]+\"([^\"]+)\")?", 0);
}
AP_DECLARE_MODULE(proxy_http) = {
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 */
};
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