Commit 738667df authored by Graham Leggett's avatar Graham Leggett
Browse files

Added Max-Forwards support for all request types so as to prevent 

loops.
PR: 1085
Obtained from:
Reviewed by:


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@88848 13f79535-47bb-0310-9956-ffa450edef68
parent 499e991e

modules/proxy/mod_proxy.c

+37 −6
Original line number Diff line number Diff line
@@ -269,15 +269,17 @@ static int proxy_handler(request_rec *r) 
    struct proxy_remote *ents = (struct proxy_remote *) proxies->elts;

    int i, rc;

    int direct_connect = 0;

    const char *maxfwd_str;

    const char *str;

    const char *pragma, *auth, *imstr;

    long maxfwd;



    /* is this for us? */

    if (!r->proxyreq || strncmp(r->filename, "proxy:", 6) != 0)

	return DECLINED;



    if ((r->method_number == M_TRACE || r->method_number == M_OPTIONS) &&

	(maxfwd_str = apr_table_get(r->headers_in, "Max-Forwards")) != NULL) {

	long maxfwd = strtol(maxfwd_str, NULL, 10);

    /* handle max-forwards / OPTIONS / TRACE */

    if ((str = apr_table_get(r->headers_in, "Max-Forwards"))) {

	maxfwd = strtol(str, NULL, 10);

	if (maxfwd < 1) {

            switch (r->method_number) {

            case M_TRACE: {
@@ -298,11 +300,20 @@ static int proxy_handler(request_rec *r) 
		    ap_finalize_request_protocol(r);

	        return OK;

            }

	    default: {

		return ap_proxyerror(r, HTTP_BAD_GATEWAY,

		                     "Max-Forwards has reached zero - proxy loop?");

	    }

            }

	apr_table_setn(r->headers_in, "Max-Forwards", 

		      apr_psprintf(r->pool, "%ld", (maxfwd > 0) ? maxfwd-1 : 0));

	}

	maxfwd = (maxfwd > 0) ? maxfwd - 1 : 0;

    }

    else {

	/* set configured max-forwards */

	maxfwd = conf->maxfwd;

    }

    apr_table_setn(r->headers_in, "Max-Forwards", 

		   apr_psprintf(r->pool, "%ld", (maxfwd > 0) ? maxfwd : 0));



    if ((rc = ap_setup_client_block(r, REQUEST_CHUNKED_ERROR)))

	return rc;
@@ -417,6 +428,8 @@ static void * create_proxy_config(apr_pool_t *p, server_rec *s) 
    ps->req_set = 0;

    ps->recv_buffer_size = 0; /* this default was left unset for some reason */

    ps->recv_buffer_size_set = 0;

    ps->maxfwd = DEFAULT_MAX_FORWARDS;

    ps->maxfwd_set = 0;



    return ps;

}
@@ -438,6 +451,7 @@ static void * merge_proxy_config(apr_pool_t *p, void *basev, void *overridesv) 
    ps->viaopt = (overrides->viaopt_set == 0) ? base->viaopt : overrides->viaopt;

    ps->req = (overrides->req_set == 0) ? base->req : overrides->req;

    ps->recv_buffer_size = (overrides->recv_buffer_size_set == 0) ? base->recv_buffer_size : overrides->recv_buffer_size;

    ps->maxfwd = (overrides->maxfwd_set == 0) ? base->maxfwd : overrides->maxfwd;



    return ps;

}
@@ -664,6 +678,21 @@ static const char * 
    return NULL;

}



static const char *

    set_max_forwards(cmd_parms *parms, void *dummy, const char *arg)

{

    proxy_server_conf *psf =

    ap_get_module_config(parms->server->module_config, &proxy_module);

    long s = atol(arg);

    if (s < 0) {

	return "ProxyMaxForwards must be greater or equal to zero..";

    }



    psf->maxfwd = s;

    psf->maxfwd_set = 1;

    return NULL;

}



static const char*

    set_via_opt(cmd_parms *parms, void *dummy, const char *arg)

{
@@ -701,6 +730,8 @@ static const command_rec proxy_cmds[] = 
     "A list of names, hosts or domains to which the proxy will not connect"),

    AP_INIT_TAKE1("ProxyReceiveBufferSize", set_recv_buffer_size, NULL, RSRC_CONF,

     "Receive buffer size for outgoing HTTP and FTP connections in bytes"),

    AP_INIT_TAKE1("ProxyMaxForwards", set_max_forwards, NULL, RSRC_CONF,

     "The maximum number of proxies a request may be forwarded through."),

    AP_INIT_ITERATE("NoProxy", set_proxy_dirconn, NULL, RSRC_CONF,

     "A list of domains, hosts, or subnets to which the proxy will connect directly"),

    AP_INIT_TAKE1("ProxyDomain", set_proxy_domain, NULL, RSRC_CONF,

modules/proxy/mod_proxy.h

+4 −0
Original line number Diff line number Diff line
@@ -134,6 +134,8 @@ enum enctype { 
#define CRLF   "\015\012"

#endif /*APR_CHARSET_EBCDIC*/



/* default Max-Forwards header setting */

#define DEFAULT_MAX_FORWARDS	10



/* static information about a remote proxy */

struct proxy_remote {
@@ -179,6 +181,8 @@ typedef struct { 
    char viaopt_set;

    size_t recv_buffer_size;

    char recv_buffer_size_set;

    long maxfwd;

    char maxfwd_set;

} proxy_server_conf;



struct per_thread_data {