Move common (and near-identical) code for CGI response output handling

to cgi_common.h; the diff between the modules for this code was as
follows:

https://people.apache.org/~jorton/mod_cgi-to-cgid-handler.diff

Change from previous: mod_cgi will now explicitly discard output when
returning HTTP_MOVED_TEMPORARILY for relative redirects (should not be
functionally different), TRACE1 logging of ap_pass_brigade failures
for mod_cgid is dropped.

* modules/generators/cgi_common.h (cgi_handle_response): New function,
  factored out from mod_cgid.
  (discard_script_output): Copied function from mod_cgi/d unchanged.

* modules/generator/mod_cgid.c (cgid_handler),
  modules/generator/mod_cgi.c (cgi_handler): Use cgi_handle_response.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1867968 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Joe Orton
2019-10-04 09:20:33 +00:00
parent 58b69a442e
commit 54c71d419a
3 changed files with 143 additions and 258 deletions

View File

@ -27,6 +27,27 @@
#include "httpd.h"
#include "util_filter.h"
static void discard_script_output(apr_bucket_brigade *bb)
{
apr_bucket *e;
const char *buf;
apr_size_t len;
apr_status_t rv;
for (e = APR_BRIGADE_FIRST(bb);
e != APR_BRIGADE_SENTINEL(bb);
e = APR_BUCKET_NEXT(e))
{
if (APR_BUCKET_IS_EOS(e)) {
break;
}
rv = apr_bucket_read(e, &buf, &len, APR_BLOCK_READ);
if (rv != APR_SUCCESS) {
break;
}
}
}
/* A CGI bucket type is needed to catch any output to stderr from the
* script; see PR 22030. */
static const apr_bucket_type_t bucket_type_cgi;
@ -218,3 +239,122 @@ static const apr_bucket_type_t bucket_type_cgi = {
apr_bucket_copy_notimpl
};
/* Handle the CGI response output, having set up the brigade with the
* CGI or PIPE bucket as appropriate. */
static int cgi_handle_response(request_rec *r, int nph, apr_bucket_brigade *bb,
apr_interval_time_t timeout, cgi_server_conf *conf,
char *logdata, apr_file_t *script_err)
{
apr_status_t rv;
/* Handle script return... */
if (!nph) {
const char *location;
char sbuf[MAX_STRING_LEN];
int ret;
if ((ret = ap_scan_script_header_err_brigade_ex(r, bb, sbuf,
APLOG_MODULE_INDEX)))
{
ret = log_script(r, conf, ret, logdata, sbuf, bb, script_err);
/*
* ret could be HTTP_NOT_MODIFIED in the case that the CGI script
* does not set an explicit status and ap_meets_conditions, which
* is called by ap_scan_script_header_err_brigade, detects that
* the conditions of the requests are met and the response is
* not modified.
* In this case set r->status and return OK in order to prevent
* running through the error processing stack as this would
* break with mod_cache, if the conditions had been set by
* mod_cache itself to validate a stale entity.
* BTW: We circumvent the error processing stack anyway if the
* CGI script set an explicit status code (whatever it is) and
* the only possible values for ret here are:
*
* HTTP_NOT_MODIFIED (set by ap_meets_conditions)
* HTTP_PRECONDITION_FAILED (set by ap_meets_conditions)
* HTTP_INTERNAL_SERVER_ERROR (if something went wrong during the
* processing of the response of the CGI script, e.g broken headers
* or a crashed CGI process).
*/
if (ret == HTTP_NOT_MODIFIED) {
r->status = ret;
return OK;
}
return ret;
}
location = apr_table_get(r->headers_out, "Location");
if (location && r->status == 200) {
/* For a redirect whether internal or not, discard any
* remaining stdout from the script, and log any remaining
* stderr output, as normal. */
discard_script_output(bb);
apr_brigade_destroy(bb);
if (script_err) {
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
}
if (location && location[0] == '/' && r->status == 200) {
/* This redirect needs to be a GET no matter what the original
* method was.
*/
r->method = "GET";
r->method_number = M_GET;
/* We already read the message body (if any), so don't allow
* the redirected request to think it has one. We can ignore
* Transfer-Encoding, since we used REQUEST_CHUNKED_ERROR.
*/
apr_table_unset(r->headers_in, "Content-Length");
ap_internal_redirect_handler(location, r);
return OK;
}
else if (location && r->status == 200) {
/* XXX: Note that if a script wants to produce its own Redirect
* body, it now has to explicitly *say* "Status: 302"
*/
discard_script_output(bb);
apr_brigade_destroy(bb);
return HTTP_MOVED_TEMPORARILY;
}
rv = ap_pass_brigade(r->output_filters, bb);
}
else /* nph */ {
struct ap_filter_t *cur;
/* get rid of all filters up through protocol... since we
* haven't parsed off the headers, there is no way they can
* work
*/
cur = r->proto_output_filters;
while (cur && cur->frec->ftype < AP_FTYPE_CONNECTION) {
cur = cur->next;
}
r->output_filters = r->proto_output_filters = cur;
rv = ap_pass_brigade(r->output_filters, bb);
}
/* don't soak up script output if errors occurred writing it
* out... otherwise, we prolong the life of the script when the
* connection drops or we stopped sending output for some other
* reason */
if (script_err && rv == APR_SUCCESS && !r->connection->aborted) {
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
if (script_err) apr_file_close(script_err);
return OK; /* NOT r->status, even if it has changed. */
}

View File

@ -568,27 +568,6 @@ static apr_status_t default_build_command(const char **cmd, const char ***argv,
return APR_SUCCESS;
}
static void discard_script_output(apr_bucket_brigade *bb)
{
apr_bucket *e;
const char *buf;
apr_size_t len;
apr_status_t rv;
for (e = APR_BRIGADE_FIRST(bb);
e != APR_BRIGADE_SENTINEL(bb);
e = APR_BUCKET_NEXT(e))
{
if (APR_BUCKET_IS_EOS(e)) {
break;
}
rv = apr_bucket_read(e, &buf, &len, APR_BLOCK_READ);
if (rv != APR_SUCCESS) {
break;
}
}
}
#if APR_FILES_AS_SOCKETS
#include "cgi_common.h"
#endif
@ -782,111 +761,7 @@ static int cgi_handler(request_rec *r)
b = apr_bucket_eos_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, b);
/* Handle script return... */
if (!nph) {
const char *location;
char sbuf[MAX_STRING_LEN];
int ret;
if ((ret = ap_scan_script_header_err_brigade_ex(r, bb, sbuf,
APLOG_MODULE_INDEX)))
{
ret = log_script(r, conf, ret, dbuf, sbuf, bb, script_err);
/*
* ret could be HTTP_NOT_MODIFIED in the case that the CGI script
* does not set an explicit status and ap_meets_conditions, which
* is called by ap_scan_script_header_err_brigade, detects that
* the conditions of the requests are met and the response is
* not modified.
* In this case set r->status and return OK in order to prevent
* running through the error processing stack as this would
* break with mod_cache, if the conditions had been set by
* mod_cache itself to validate a stale entity.
* BTW: We circumvent the error processing stack anyway if the
* CGI script set an explicit status code (whatever it is) and
* the only possible values for ret here are:
*
* HTTP_NOT_MODIFIED (set by ap_meets_conditions)
* HTTP_PRECONDITION_FAILED (set by ap_meets_conditions)
* HTTP_INTERNAL_SERVER_ERROR (if something went wrong during the
* processing of the response of the CGI script, e.g broken headers
* or a crashed CGI process).
*/
if (ret == HTTP_NOT_MODIFIED) {
r->status = ret;
return OK;
}
return ret;
}
location = apr_table_get(r->headers_out, "Location");
if (location && r->status == 200) {
/* For a redirect whether internal or not, discard any
* remaining stdout from the script, and log any remaining
* stderr output, as normal. */
discard_script_output(bb);
apr_brigade_destroy(bb);
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
if (location && location[0] == '/' && r->status == 200) {
/* This redirect needs to be a GET no matter what the original
* method was.
*/
r->method = "GET";
r->method_number = M_GET;
/* We already read the message body (if any), so don't allow
* the redirected request to think it has one. We can ignore
* Transfer-Encoding, since we used REQUEST_CHUNKED_ERROR.
*/
apr_table_unset(r->headers_in, "Content-Length");
ap_internal_redirect_handler(location, r);
return OK;
}
else if (location && r->status == 200) {
/* XXX: Note that if a script wants to produce its own Redirect
* body, it now has to explicitly *say* "Status: 302"
*/
return HTTP_MOVED_TEMPORARILY;
}
rv = ap_pass_brigade(r->output_filters, bb);
}
else /* nph */ {
struct ap_filter_t *cur;
/* get rid of all filters up through protocol... since we
* haven't parsed off the headers, there is no way they can
* work
*/
cur = r->proto_output_filters;
while (cur && cur->frec->ftype < AP_FTYPE_CONNECTION) {
cur = cur->next;
}
r->output_filters = r->proto_output_filters = cur;
rv = ap_pass_brigade(r->output_filters, bb);
}
/* don't soak up script output if errors occurred writing it
* out... otherwise, we prolong the life of the script when the
* connection drops or we stopped sending output for some other
* reason */
if (rv == APR_SUCCESS && !r->connection->aborted) {
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
apr_file_close(script_err);
return OK; /* NOT r->status, even if it has changed. */
return cgi_handle_response(r, nph, bb, timeout, conf, dbuf, script_err);
}
/*============================================================================

View File

@ -1351,6 +1351,7 @@ static int log_script(request_rec *r, cgid_server_conf * conf, int ret,
#ifdef HAVE_CGID_FDPASSING
/* Pull in CGI bucket implementation. */
#define cgi_server_conf cgid_server_conf
#include "cgi_common.h"
#endif
@ -1420,27 +1421,6 @@ static int connect_to_daemon(int *sdptr, request_rec *r,
return OK;
}
static void discard_script_output(apr_bucket_brigade *bb)
{
apr_bucket *e;
const char *buf;
apr_size_t len;
apr_status_t rv;
for (e = APR_BRIGADE_FIRST(bb);
e != APR_BRIGADE_SENTINEL(bb);
e = APR_BUCKET_NEXT(e))
{
if (APR_BUCKET_IS_EOS(e)) {
break;
}
rv = apr_bucket_read(e, &buf, &len, APR_BLOCK_READ);
if (rv != APR_SUCCESS) {
break;
}
}
}
/****************************************************************
*
* Actual cgid handling...
@ -1779,117 +1759,7 @@ static int cgid_handler(request_rec *r)
b = apr_bucket_eos_create(c->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, b);
/* Handle script return... */
if (!nph) {
const char *location;
char sbuf[MAX_STRING_LEN];
int ret;
if ((ret = ap_scan_script_header_err_brigade_ex(r, bb, sbuf,
APLOG_MODULE_INDEX)))
{
ret = log_script(r, conf, ret, dbuf, sbuf, bb, script_err);
/*
* ret could be HTTP_NOT_MODIFIED in the case that the CGI script
* does not set an explicit status and ap_meets_conditions, which
* is called by ap_scan_script_header_err_brigade, detects that
* the conditions of the requests are met and the response is
* not modified.
* In this case set r->status and return OK in order to prevent
* running through the error processing stack as this would
* break with mod_cache, if the conditions had been set by
* mod_cache itself to validate a stale entity.
* BTW: We circumvent the error processing stack anyway if the
* CGI script set an explicit status code (whatever it is) and
* the only possible values for ret here are:
*
* HTTP_NOT_MODIFIED (set by ap_meets_conditions)
* HTTP_PRECONDITION_FAILED (set by ap_meets_conditions)
* HTTP_INTERNAL_SERVER_ERROR (if something went wrong during the
* processing of the response of the CGI script, e.g broken headers
* or a crashed CGI process).
*/
if (ret == HTTP_NOT_MODIFIED) {
r->status = ret;
return OK;
}
return ret;
}
location = apr_table_get(r->headers_out, "Location");
if (location && location[0] == '/' && r->status == 200) {
/* Soak up all the script output */
discard_script_output(bb);
apr_brigade_destroy(bb);
if (script_err) {
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
/* This redirect needs to be a GET no matter what the original
* method was.
*/
r->method = "GET";
r->method_number = M_GET;
/* We already read the message body (if any), so don't allow
* the redirected request to think it has one. We can ignore
* Transfer-Encoding, since we used REQUEST_CHUNKED_ERROR.
*/
apr_table_unset(r->headers_in, "Content-Length");
ap_internal_redirect_handler(location, r);
return OK;
}
else if (location && r->status == 200) {
/* XXX: Note that if a script wants to produce its own Redirect
* body, it now has to explicitly *say* "Status: 302"
*/
discard_script_output(bb);
apr_brigade_destroy(bb);
return HTTP_MOVED_TEMPORARILY;
}
rv = ap_pass_brigade(r->output_filters, bb);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_TRACE1, rv, r,
"Failed to flush CGI output to client");
}
}
if (nph) {
struct ap_filter_t *cur;
/* get rid of all filters up through protocol... since we
* haven't parsed off the headers, there is no way they can
* work
*/
cur = r->proto_output_filters;
while (cur && cur->frec->ftype < AP_FTYPE_CONNECTION) {
cur = cur->next;
}
r->output_filters = r->proto_output_filters = cur;
rv = ap_pass_brigade(r->output_filters, bb);
}
/* don't soak up script output if errors occurred writing it
* out... otherwise, we prolong the life of the script when the
* connection drops or we stopped sending output for some other
* reason */
if (script_err && rv == APR_SUCCESS && !r->connection->aborted) {
apr_file_pipe_timeout_set(script_err, timeout);
log_script_err(r, script_err);
}
if (script_err) apr_file_close(script_err);
return OK; /* NOT r->status, even if it has changed. */
return cgi_handle_response(r, nph, bb, timeout, conf, dbuf, script_err);
}