mod_cgi.c revision 7619b51fca6ecf16c28389e52a666e82f3c8d3ef
/* 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_script: keeps all script-related ramblings together.
*
* Compliant to CGI/1.1 spec
*
* Adapted by rst from original NCSA code by Rob McCool
*
* Apache adds some new env vars; REDIRECT_URL and REDIRECT_QUERY_STRING for
* custom error responses, and DOCUMENT_ROOT because we found it useful.
* It also adds SERVER_ADMIN - useful for scripts to know who to mail when
* they fail.
*/
#include "apr.h"
#include "apr_strings.h"
#include "apr_thread_proc.h" /* for RLIMIT stuff */
#include "apr_optional.h"
#include "apr_buckets.h"
#include "apr_lib.h"
#include "apr_poll.h"
#define APR_WANT_STRFUNC
#define APR_WANT_MEMFUNC
#include "apr_want.h"
#include "util_filter.h"
#include "ap_config.h"
#include "httpd.h"
#include "http_config.h"
#include "http_request.h"
#include "http_core.h"
#include "http_protocol.h"
#include "http_main.h"
#include "http_log.h"
#include "util_script.h"
#include "ap_mpm.h"
#include "mod_core.h"
#include "mod_cgi.h"
#if APR_HAVE_STRUCT_RLIMIT
#if defined (RLIMIT_CPU) || defined (RLIMIT_NPROC) || defined (RLIMIT_DATA) || defined(RLIMIT_VMEM) || defined(RLIMIT_AS)
#define AP_CGI_USE_RLIMIT
#endif
#endif
module AP_MODULE_DECLARE_DATA cgi_module;
static APR_OPTIONAL_FN_TYPE(ap_register_include_handler) *cgi_pfn_reg_with_ssi;
static APR_OPTIONAL_FN_TYPE(ap_ssi_get_tag_and_value) *cgi_pfn_gtv;
static APR_OPTIONAL_FN_TYPE(ap_ssi_parse_string) *cgi_pfn_ps;
static APR_OPTIONAL_FN_TYPE(ap_cgi_build_command) *cgi_build_command;
/* Read and discard the data in the brigade produced by a CGI script */
static void discard_script_output(apr_bucket_brigade *bb);
/* KLUDGE --- for back-combatibility, we don't have to check ExecCGI
* in ScriptAliased directories, which means we need to know if this
* request came through ScriptAlias or not... so the Alias module
* leaves a note for us.
*/
static int is_scriptaliased(request_rec *r)
{
const char *t = apr_table_get(r->notes, "alias-forced-type");
return t && (!strcasecmp(t, "cgi-script"));
}
/* Configuration stuff */
#define DEFAULT_LOGBYTES 10385760
#define DEFAULT_BUFBYTES 1024
typedef struct {
const char *logname;
long logbytes;
apr_size_t bufbytes;
} cgi_server_conf;
static void *create_cgi_config(apr_pool_t *p, server_rec *s)
{
cgi_server_conf *c =
(cgi_server_conf *) apr_pcalloc(p, sizeof(cgi_server_conf));
c->logname = NULL;
c->logbytes = DEFAULT_LOGBYTES;
c->bufbytes = DEFAULT_BUFBYTES;
return c;
}
static void *merge_cgi_config(apr_pool_t *p, void *basev, void *overridesv)
{
cgi_server_conf *base = (cgi_server_conf *) basev,
*overrides = (cgi_server_conf *) overridesv;
return overrides->logname ? overrides : base;
}
static const char *set_scriptlog(cmd_parms *cmd, void *dummy, const char *arg)
{
server_rec *s = cmd->server;
cgi_server_conf *conf = ap_get_module_config(s->module_config,
&cgi_module);
conf->logname = ap_server_root_relative(cmd->pool, arg);
if (!conf->logname) {
return apr_pstrcat(cmd->pool, "Invalid ScriptLog path ",
arg, NULL);
}
return NULL;
}
static const char *set_scriptlog_length(cmd_parms *cmd, void *dummy,
const char *arg)
{
server_rec *s = cmd->server;
cgi_server_conf *conf = ap_get_module_config(s->module_config,
&cgi_module);
conf->logbytes = atol(arg);
return NULL;
}
static const char *set_scriptlog_buffer(cmd_parms *cmd, void *dummy,
const char *arg)
{
server_rec *s = cmd->server;
cgi_server_conf *conf = ap_get_module_config(s->module_config,
&cgi_module);
conf->bufbytes = atoi(arg);
return NULL;
}
static const command_rec cgi_cmds[] =
{
AP_INIT_TAKE1("ScriptLog", set_scriptlog, NULL, RSRC_CONF,
"the name of a log for script debugging info"),
AP_INIT_TAKE1("ScriptLogLength", set_scriptlog_length, NULL, RSRC_CONF,
"the maximum length (in bytes) of the script debug log"),
AP_INIT_TAKE1("ScriptLogBuffer", set_scriptlog_buffer, NULL, RSRC_CONF,
"the maximum size (in bytes) to record of a POST request"),
{NULL}
};
static int log_scripterror(request_rec *r, cgi_server_conf * conf, int ret,
apr_status_t rv, char *error)
{
apr_file_t *f = NULL;
apr_finfo_t finfo;
char time_str[APR_CTIME_LEN];
int log_flags = rv ? APLOG_ERR : APLOG_ERR;
ap_log_rerror(APLOG_MARK, log_flags, rv, r,
"%s: %s", error, r->filename);
/* XXX Very expensive mainline case! Open, then getfileinfo! */
if (!conf->logname ||
((apr_stat(&finfo, conf->logname,
APR_FINFO_SIZE, r->pool) == APR_SUCCESS) &&
(finfo.size > conf->logbytes)) ||
(apr_file_open(&f, conf->logname,
APR_APPEND|APR_WRITE|APR_CREATE, APR_OS_DEFAULT,
r->pool) != APR_SUCCESS)) {
return ret;
}
/* "%% [Wed Jun 19 10:53:21 1996] GET /cgi-bin/printenv HTTP/1.0" */
apr_ctime(time_str, apr_time_now());
apr_file_printf(f, "%%%% [%s] %s %s%s%s %s\n", time_str, r->method, r->uri,
r->args ? "?" : "", r->args ? r->args : "", r->protocol);
/* "%% 500 /usr/local/apache/cgi-bin */
apr_file_printf(f, "%%%% %d %s\n", ret, r->filename);
apr_file_printf(f, "%%error\n%s\n", error);
apr_file_close(f);
return ret;
}
/* Soak up stderr from a script and redirect it to the error log.
*/
static apr_status_t log_script_err(request_rec *r, apr_file_t *script_err)
{
char argsbuffer[HUGE_STRING_LEN];
char *newline;
apr_status_t rv;
while ((rv = apr_file_gets(argsbuffer, HUGE_STRING_LEN,
script_err)) == APR_SUCCESS) {
newline = strchr(argsbuffer, '\n');
if (newline) {
*newline = '\0';
}
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01215)
"%s", argsbuffer);
}
return rv;
}
static int log_script(request_rec *r, cgi_server_conf * conf, int ret,
char *dbuf, const char *sbuf, apr_bucket_brigade *bb,
apr_file_t *script_err)
{
const apr_array_header_t *hdrs_arr = apr_table_elts(r->headers_in);
const apr_table_entry_t *hdrs = (const apr_table_entry_t *) hdrs_arr->elts;
char argsbuffer[HUGE_STRING_LEN];
apr_file_t *f = NULL;
apr_bucket *e;
const char *buf;
apr_size_t len;
apr_status_t rv;
int first;
int i;
apr_finfo_t finfo;
char time_str[APR_CTIME_LEN];
/* XXX Very expensive mainline case! Open, then getfileinfo! */
if (!conf->logname ||
((apr_stat(&finfo, conf->logname,
APR_FINFO_SIZE, r->pool) == APR_SUCCESS) &&
(finfo.size > conf->logbytes)) ||
(apr_file_open(&f, conf->logname,
APR_APPEND|APR_WRITE|APR_CREATE, APR_OS_DEFAULT,
r->pool) != APR_SUCCESS)) {
/* Soak up script output */
discard_script_output(bb);
log_script_err(r, script_err);
return ret;
}
/* "%% [Wed Jun 19 10:53:21 1996] GET /cgi-bin/printenv HTTP/1.0" */
apr_ctime(time_str, apr_time_now());
apr_file_printf(f, "%%%% [%s] %s %s%s%s %s\n", time_str, r->method, r->uri,
r->args ? "?" : "", r->args ? r->args : "", r->protocol);
/* "%% 500 /usr/local/apache/cgi-bin" */
apr_file_printf(f, "%%%% %d %s\n", ret, r->filename);
apr_file_puts("%request\n", f);
for (i = 0; i < hdrs_arr->nelts; ++i) {
if (!hdrs[i].key)
continue;
apr_file_printf(f, "%s: %s\n", hdrs[i].key, hdrs[i].val);
}
if ((r->method_number == M_POST || r->method_number == M_PUT) &&
*dbuf) {
apr_file_printf(f, "\n%s\n", dbuf);
}
apr_file_puts("%response\n", f);
hdrs_arr = apr_table_elts(r->err_headers_out);
hdrs = (const apr_table_entry_t *) hdrs_arr->elts;
for (i = 0; i < hdrs_arr->nelts; ++i) {
if (!hdrs[i].key)
continue;
apr_file_printf(f, "%s: %s\n", hdrs[i].key, hdrs[i].val);
}
if (sbuf && *sbuf)
apr_file_printf(f, "%s\n", sbuf);
first = 1;
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 || (len == 0)) {
break;
}
if (first) {
apr_file_puts("%stdout\n", f);
first = 0;
}
apr_file_write(f, buf, &len);
apr_file_puts("\n", f);
}
if (apr_file_gets(argsbuffer, HUGE_STRING_LEN, script_err) == APR_SUCCESS) {
apr_file_puts("%stderr\n", f);
apr_file_puts(argsbuffer, f);
while (apr_file_gets(argsbuffer, HUGE_STRING_LEN,
script_err) == APR_SUCCESS) {
apr_file_puts(argsbuffer, f);
}
apr_file_puts("\n", f);
}
apr_brigade_destroy(bb);
apr_file_close(script_err);
apr_file_close(f);
return ret;
}
/* This is the special environment used for running the "exec cmd="
* variety of SSI directives.
*/
static void add_ssi_vars(request_rec *r)
{
apr_table_t *e = r->subprocess_env;
if (r->path_info && r->path_info[0] != '\0') {
request_rec *pa_req;
apr_table_setn(e, "PATH_INFO", ap_escape_shell_cmd(r->pool,
r->path_info));
pa_req = ap_sub_req_lookup_uri(ap_escape_uri(r->pool, r->path_info),
r, NULL);
if (pa_req->filename) {
apr_table_setn(e, "PATH_TRANSLATED",
apr_pstrcat(r->pool, pa_req->filename,
pa_req->path_info, NULL));
}
ap_destroy_sub_req(pa_req);
}
if (r->args) {
char *arg_copy = apr_pstrdup(r->pool, r->args);
apr_table_setn(e, "QUERY_STRING", r->args);
ap_unescape_url(arg_copy);
apr_table_setn(e, "QUERY_STRING_UNESCAPED",
ap_escape_shell_cmd(r->pool, arg_copy));
}
}
static void cgi_child_errfn(apr_pool_t *pool, apr_status_t err,
const char *description)
{
apr_file_t *stderr_log;
apr_file_open_stderr(&stderr_log, pool);
/* Escape the logged string because it may be something that
* came in over the network.
*/
apr_file_printf(stderr_log,
"(%d)%pm: %s\n",
err,
&err,
#ifndef AP_UNSAFE_ERROR_LOG_UNESCAPED
ap_escape_logitem(pool,
#endif
description
#ifndef AP_UNSAFE_ERROR_LOG_UNESCAPED
)
#endif
);
}
static apr_status_t run_cgi_child(apr_file_t **script_out,
apr_file_t **script_in,
apr_file_t **script_err,
const char *command,
const char * const argv[],
request_rec *r,
apr_pool_t *p,
cgi_exec_info_t *e_info)
{
const char * const *env;
apr_procattr_t *procattr;
apr_proc_t *procnew;
apr_status_t rc = APR_SUCCESS;
#ifdef AP_CGI_USE_RLIMIT
core_dir_config *conf = ap_get_core_module_config(r->per_dir_config);
#endif
#ifdef DEBUG_CGI
#ifdef OS2
/* Under OS/2 need to use device con. */
FILE *dbg = fopen("con", "w");
#else
FILE *dbg = fopen("/dev/tty", "w");
#endif
int i;
#endif
RAISE_SIGSTOP(CGI_CHILD);
#ifdef DEBUG_CGI
fprintf(dbg, "Attempting to exec %s as CGI child (argv0 = %s)\n",
r->filename, argv[0]);
#endif
env = (const char * const *)ap_create_environment(p, r->subprocess_env);
#ifdef DEBUG_CGI
fprintf(dbg, "Environment: \n");
for (i = 0; env[i]; ++i)
fprintf(dbg, "'%s'\n", env[i]);
fclose(dbg);
#endif
/* Transmute ourselves into the script.
* NB only ISINDEX scripts get decoded arguments.
*/
if (((rc = apr_procattr_create(&procattr, p)) != APR_SUCCESS) ||
((rc = apr_procattr_io_set(procattr,
e_info->in_pipe,
e_info->out_pipe,
e_info->err_pipe)) != APR_SUCCESS) ||
((rc = apr_procattr_dir_set(procattr,
ap_make_dirstr_parent(r->pool,
r->filename))) != APR_SUCCESS) ||
#if defined(RLIMIT_CPU) && defined(AP_CGI_USE_RLIMIT)
((rc = apr_procattr_limit_set(procattr, APR_LIMIT_CPU,
conf->limit_cpu)) != APR_SUCCESS) ||
#endif
#if defined(AP_CGI_USE_RLIMIT) && (defined(RLIMIT_DATA) || defined(RLIMIT_VMEM) || defined(RLIMIT_AS))
((rc = apr_procattr_limit_set(procattr, APR_LIMIT_MEM,
conf->limit_mem)) != APR_SUCCESS) ||
#endif
#if defined(RLIMIT_NPROC) && defined(AP_CGI_USE_RLIMIT)
((rc = apr_procattr_limit_set(procattr, APR_LIMIT_NPROC,
conf->limit_nproc)) != APR_SUCCESS) ||
#endif
((rc = apr_procattr_cmdtype_set(procattr,
e_info->cmd_type)) != APR_SUCCESS) ||
((rc = apr_procattr_detach_set(procattr,
e_info->detached)) != APR_SUCCESS) ||
((rc = apr_procattr_addrspace_set(procattr,
e_info->addrspace)) != APR_SUCCESS) ||
((rc = apr_procattr_child_errfn_set(procattr, cgi_child_errfn)) != APR_SUCCESS)) {
/* Something bad happened, tell the world. */
ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r, APLOGNO(01216)
"couldn't set child process attributes: %s", r->filename);
}
else {
procnew = apr_pcalloc(p, sizeof(*procnew));
rc = ap_os_create_privileged_process(r, procnew, command, argv, env,
procattr, p);
if (rc != APR_SUCCESS) {
/* Bad things happened. Everyone should have cleaned up. */
ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_TOCLIENT, rc, r,
"couldn't create child process: %d: %s", rc,
apr_filepath_name_get(r->filename));
}
else {
apr_pool_note_subprocess(p, procnew, APR_KILL_AFTER_TIMEOUT);
*script_in = procnew->out;
if (!*script_in)
return APR_EBADF;
apr_file_pipe_timeout_set(*script_in, r->server->timeout);
if (e_info->prog_type == RUN_AS_CGI) {
*script_out = procnew->in;
if (!*script_out)
return APR_EBADF;
apr_file_pipe_timeout_set(*script_out, r->server->timeout);
*script_err = procnew->err;
if (!*script_err)
return APR_EBADF;
apr_file_pipe_timeout_set(*script_err, r->server->timeout);
}
}
}
return (rc);
}
static apr_status_t default_build_command(const char **cmd, const char ***argv,
request_rec *r, apr_pool_t *p,
cgi_exec_info_t *e_info)
{
int numwords, x, idx;
char *w;
const char *args = NULL;
if (e_info->process_cgi) {
*cmd = r->filename;
/* Do not process r->args if they contain an '=' assignment
*/
if (r->args && r->args[0] && !ap_strchr_c(r->args, '=')) {
args = r->args;
}
}
if (!args) {
numwords = 1;
}
else {
/* count the number of keywords */
for (x = 0, numwords = 2; args[x]; x++) {
if (args[x] == '+') {
++numwords;
}
}
}
/* Everything is - 1 to account for the first parameter
* which is the program name.
*/
if (numwords > APACHE_ARG_MAX - 1) {
numwords = APACHE_ARG_MAX - 1; /* Truncate args to prevent overrun */
}
*argv = apr_palloc(p, (numwords + 2) * sizeof(char *));
(*argv)[0] = *cmd;
for (x = 1, idx = 1; x < numwords; x++) {
w = ap_getword_nulls(p, &args, '+');
ap_unescape_url(w);
(*argv)[idx++] = ap_escape_shell_cmd(p, w);
}
(*argv)[idx] = NULL;
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
/* 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;
struct cgi_bucket_data {
apr_pollset_t *pollset;
request_rec *r;
};
/* Create a CGI bucket using pipes from script stdout 'out'
* and stderr 'err', for request 'r'. */
static apr_bucket *cgi_bucket_create(request_rec *r,
apr_file_t *out, apr_file_t *err,
apr_bucket_alloc_t *list)
{
apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
apr_status_t rv;
apr_pollfd_t fd;
struct cgi_bucket_data *data = apr_palloc(r->pool, sizeof *data);
APR_BUCKET_INIT(b);
b->free = apr_bucket_free;
b->list = list;
b->type = &bucket_type_cgi;
b->length = (apr_size_t)(-1);
b->start = -1;
/* Create the pollset */
rv = apr_pollset_create(&data->pollset, 2, r->pool, 0);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01217)
"apr_pollset_create(); check system or user limits");
return NULL;
}
fd.desc_type = APR_POLL_FILE;
fd.reqevents = APR_POLLIN;
fd.p = r->pool;
fd.desc.f = out; /* script's stdout */
fd.client_data = (void *)1;
rv = apr_pollset_add(data->pollset, &fd);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01218)
"apr_pollset_add(); check system or user limits");
return NULL;
}
fd.desc.f = err; /* script's stderr */
fd.client_data = (void *)2;
rv = apr_pollset_add(data->pollset, &fd);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01219)
"apr_pollset_add(); check system or user limits");
return NULL;
}
data->r = r;
b->data = data;
return b;
}
/* Create a duplicate CGI bucket using given bucket data */
static apr_bucket *cgi_bucket_dup(struct cgi_bucket_data *data,
apr_bucket_alloc_t *list)
{
apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
APR_BUCKET_INIT(b);
b->free = apr_bucket_free;
b->list = list;
b->type = &bucket_type_cgi;
b->length = (apr_size_t)(-1);
b->start = -1;
b->data = data;
return b;
}
/* Handle stdout from CGI child. Duplicate of logic from the _read
* method of the real APR pipe bucket implementation. */
static apr_status_t cgi_read_stdout(apr_bucket *a, apr_file_t *out,
const char **str, apr_size_t *len)
{
char *buf;
apr_status_t rv;
*str = NULL;
*len = APR_BUCKET_BUFF_SIZE;
buf = apr_bucket_alloc(*len, a->list); /* XXX: check for failure? */
rv = apr_file_read(out, buf, len);
if (rv != APR_SUCCESS && rv != APR_EOF) {
apr_bucket_free(buf);
return rv;
}
if (*len > 0) {
struct cgi_bucket_data *data = a->data;
apr_bucket_heap *h;
/* Change the current bucket to refer to what we read */
a = apr_bucket_heap_make(a, buf, *len, apr_bucket_free);
h = a->data;
h->alloc_len = APR_BUCKET_BUFF_SIZE; /* note the real buffer size */
*str = buf;
APR_BUCKET_INSERT_AFTER(a, cgi_bucket_dup(data, a->list));
}
else {
apr_bucket_free(buf);
a = apr_bucket_immortal_make(a, "", 0);
*str = a->data;
}
return rv;
}
/* Read method of CGI bucket: polls on stderr and stdout of the child,
* sending any stderr output immediately away to the error log. */
static apr_status_t cgi_bucket_read(apr_bucket *b, const char **str,
apr_size_t *len, apr_read_type_e block)
{
struct cgi_bucket_data *data = b->data;
apr_interval_time_t timeout;
apr_status_t rv;
int gotdata = 0;
timeout = block == APR_NONBLOCK_READ ? 0 : data->r->server->timeout;
do {
const apr_pollfd_t *results;
apr_int32_t num;
rv = apr_pollset_poll(data->pollset, timeout, &num, &results);
if (APR_STATUS_IS_TIMEUP(rv)) {
if (timeout) {
ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, data->r, APLOGNO(01220)
"Timeout waiting for output from CGI script %s",
data->r->filename);
return rv;
}
else {
return APR_EAGAIN;
}
}
else if (APR_STATUS_IS_EINTR(rv)) {
continue;
}
else if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, data->r, APLOGNO(01221)
"poll failed waiting for CGI child");
return rv;
}
for (; num; num--, results++) {
if (results[0].client_data == (void *)1) {
/* stdout */
rv = cgi_read_stdout(b, results[0].desc.f, str, len);
if (APR_STATUS_IS_EOF(rv)) {
rv = APR_SUCCESS;
}
gotdata = 1;
} else {
/* stderr */
apr_status_t rv2 = log_script_err(data->r, results[0].desc.f);
if (APR_STATUS_IS_EOF(rv2)) {
apr_pollset_remove(data->pollset, &results[0]);
}
}
}
} while (!gotdata);
return rv;
}
static const apr_bucket_type_t bucket_type_cgi = {
"CGI", 5, APR_BUCKET_DATA,
apr_bucket_destroy_noop,
cgi_bucket_read,
apr_bucket_setaside_notimpl,
apr_bucket_split_notimpl,
apr_bucket_copy_notimpl
};
#endif
static int cgi_handler(request_rec *r)
{
int nph;
apr_size_t dbpos = 0;
const char *argv0;
const char *command;
const char **argv;
char *dbuf = NULL;
apr_file_t *script_out = NULL, *script_in = NULL, *script_err = NULL;
apr_bucket_brigade *bb;
apr_bucket *b;
int is_included;
int seen_eos, child_stopped_reading;
apr_pool_t *p;
cgi_server_conf *conf;
apr_status_t rv;
cgi_exec_info_t e_info;
conn_rec *c;
if (strcmp(r->handler, CGI_MAGIC_TYPE) && strcmp(r->handler, "cgi-script")) {
return DECLINED;
}
c = r->connection;
is_included = !strcmp(r->protocol, "INCLUDED");
p = r->main ? r->main->pool : r->pool;
argv0 = apr_filepath_name_get(r->filename);
nph = !(strncmp(argv0, "nph-", 4));
conf = ap_get_module_config(r->server->module_config, &cgi_module);
if (!(ap_allow_options(r) & OPT_EXECCGI) && !is_scriptaliased(r))
return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
"Options ExecCGI is off in this directory");
if (nph && is_included)
return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
"attempt to include NPH CGI script");
if (r->finfo.filetype == APR_NOFILE)
return log_scripterror(r, conf, HTTP_NOT_FOUND, 0,
"script not found or unable to stat");
if (r->finfo.filetype == APR_DIR)
return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
"attempt to invoke directory as script");
if ((r->used_path_info == AP_REQ_REJECT_PATH_INFO) &&
r->path_info && *r->path_info)
{
/* default to accept */
return log_scripterror(r, conf, HTTP_NOT_FOUND, 0,
"AcceptPathInfo off disallows user's path");
}
/*
if (!ap_suexec_enabled) {
if (!ap_can_exec(&r->finfo))
return log_scripterror(r, conf, HTTP_FORBIDDEN, 0,
"file permissions deny server execution");
}
*/
ap_add_common_vars(r);
ap_add_cgi_vars(r);
e_info.process_cgi = 1;
e_info.cmd_type = APR_PROGRAM;
e_info.detached = 0;
e_info.in_pipe = APR_CHILD_BLOCK;
e_info.out_pipe = APR_CHILD_BLOCK;
e_info.err_pipe = APR_CHILD_BLOCK;
e_info.prog_type = RUN_AS_CGI;
e_info.bb = NULL;
e_info.ctx = NULL;
e_info.next = NULL;
e_info.addrspace = 0;
/* build the command line */
if ((rv = cgi_build_command(&command, &argv, r, p, &e_info)) != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01222)
"don't know how to spawn child process: %s",
r->filename);
return HTTP_INTERNAL_SERVER_ERROR;
}
/* run the script in its own process */
if ((rv = run_cgi_child(&script_out, &script_in, &script_err,
command, argv, r, p, &e_info)) != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01223)
"couldn't spawn child process: %s", r->filename);
return HTTP_INTERNAL_SERVER_ERROR;
}
/* Transfer any put/post args, CERN style...
* Note that we already ignore SIGPIPE in the core server.
*/
bb = apr_brigade_create(r->pool, c->bucket_alloc);
seen_eos = 0;
child_stopped_reading = 0;
if (conf->logname) {
dbuf = apr_palloc(r->pool, conf->bufbytes + 1);
dbpos = 0;
}
do {
apr_bucket *bucket;
rv = ap_get_brigade(r->input_filters, bb, AP_MODE_READBYTES,
APR_BLOCK_READ, HUGE_STRING_LEN);
if (rv != APR_SUCCESS) {
if (APR_STATUS_IS_TIMEUP(rv)) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01224)
"Timeout during reading request entity data");
return HTTP_REQUEST_TIME_OUT;
}
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01225)
"Error reading request entity data");
return ap_map_http_request_error(rv, HTTP_INTERNAL_SERVER_ERROR);
}
for (bucket = APR_BRIGADE_FIRST(bb);
bucket != APR_BRIGADE_SENTINEL(bb);
bucket = APR_BUCKET_NEXT(bucket))
{
const char *data;
apr_size_t len;
if (APR_BUCKET_IS_EOS(bucket)) {
seen_eos = 1;
break;
}
/* We can't do much with this. */
if (APR_BUCKET_IS_FLUSH(bucket)) {
continue;
}
/* If the child stopped, we still must read to EOS. */
if (child_stopped_reading) {
continue;
}
/* read */
apr_bucket_read(bucket, &data, &len, APR_BLOCK_READ);
if (conf->logname && dbpos < conf->bufbytes) {
int cursize;
if ((dbpos + len) > conf->bufbytes) {
cursize = conf->bufbytes - dbpos;
}
else {
cursize = len;
}
memcpy(dbuf + dbpos, data, cursize);
dbpos += cursize;
}
/* Keep writing data to the child until done or too much time
* elapses with no progress or an error occurs.
*/
rv = apr_file_write_full(script_out, data, len, NULL);
if (rv != APR_SUCCESS) {
/* silly script stopped reading, soak up remaining message */
child_stopped_reading = 1;
}
}
apr_brigade_cleanup(bb);
}
while (!seen_eos);
if (conf->logname) {
dbuf[dbpos] = '\0';
}
/* Is this flush really needed? */
apr_file_flush(script_out);
apr_file_close(script_out);
AP_DEBUG_ASSERT(script_in != NULL);
#if APR_FILES_AS_SOCKETS
apr_file_pipe_timeout_set(script_in, 0);
apr_file_pipe_timeout_set(script_err, 0);
b = cgi_bucket_create(r, script_in, script_err, c->bucket_alloc);
if (b == NULL)
return HTTP_INTERNAL_SERVER_ERROR;
#else
b = apr_bucket_pipe_create(script_in, c->bucket_alloc);
#endif
APR_BRIGADE_INSERT_TAIL(bb, b);
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, r->server->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, r->server->timeout);
log_script_err(r, script_err);
}
apr_file_close(script_err);
return OK; /* NOT r->status, even if it has changed. */
}
/*============================================================================
*============================================================================
* This is the beginning of the cgi filter code moved from mod_include. This
* is the code required to handle the "exec" SSI directive.
*============================================================================
*============================================================================*/
static apr_status_t include_cgi(include_ctx_t *ctx, ap_filter_t *f,
apr_bucket_brigade *bb, char *s)
{
request_rec *r = f->r;
request_rec *rr = ap_sub_req_lookup_uri(s, r, f->next);
int rr_status;
if (rr->status != HTTP_OK) {
ap_destroy_sub_req(rr);
return APR_EGENERAL;
}
/* No hardwired path info or query allowed */
if ((rr->path_info && rr->path_info[0]) || rr->args) {
ap_destroy_sub_req(rr);
return APR_EGENERAL;
}
if (rr->finfo.filetype != APR_REG) {
ap_destroy_sub_req(rr);
return APR_EGENERAL;
}
/* Script gets parameters of the *document*, for back compatibility */
rr->path_info = r->path_info; /* hard to get right; see mod_cgi.c */
rr->args = r->args;
/* Force sub_req to be treated as a CGI request, even if ordinary
* typing rules would have called it something else.
*/
ap_set_content_type(rr, CGI_MAGIC_TYPE);
/* Run it. */
rr_status = ap_run_sub_req(rr);
if (ap_is_HTTP_REDIRECT(rr_status)) {
const char *location = apr_table_get(rr->headers_out, "Location");
if (location) {
char *buffer;
location = ap_escape_html(rr->pool, location);
buffer = apr_pstrcat(ctx->pool, "<a href=\"", location, "\">",
location, "</a>", NULL);
APR_BRIGADE_INSERT_TAIL(bb, apr_bucket_pool_create(buffer,
strlen(buffer), ctx->pool,
f->c->bucket_alloc));
}
}
ap_destroy_sub_req(rr);
return APR_SUCCESS;
}
static apr_status_t include_cmd(include_ctx_t *ctx, ap_filter_t *f,
apr_bucket_brigade *bb, const char *command)
{
cgi_exec_info_t e_info;
const char **argv;
apr_file_t *script_out = NULL, *script_in = NULL, *script_err = NULL;
apr_status_t rv;
request_rec *r = f->r;
add_ssi_vars(r);
e_info.process_cgi = 0;
e_info.cmd_type = APR_SHELLCMD;
e_info.detached = 0;
e_info.in_pipe = APR_NO_PIPE;
e_info.out_pipe = APR_FULL_BLOCK;
e_info.err_pipe = APR_NO_PIPE;
e_info.prog_type = RUN_AS_SSI;
e_info.bb = &bb;
e_info.ctx = ctx;
e_info.next = f->next;
e_info.addrspace = 0;
if ((rv = cgi_build_command(&command, &argv, r, r->pool,
&e_info)) != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01226)
"don't know how to spawn cmd child process: %s",
r->filename);
return rv;
}
/* run the script in its own process */
if ((rv = run_cgi_child(&script_out, &script_in, &script_err,
command, argv, r, r->pool,
&e_info)) != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01227)
"couldn't spawn child process: %s", r->filename);
return rv;
}
APR_BRIGADE_INSERT_TAIL(bb, apr_bucket_pipe_create(script_in,
f->c->bucket_alloc));
ctx->flush_now = 1;
/* We can't close the pipe here, because we may return before the
* full CGI has been sent to the network. That's okay though,
* because we can rely on the pool to close the pipe for us.
*/
return APR_SUCCESS;
}
static apr_status_t handle_exec(include_ctx_t *ctx, ap_filter_t *f,
apr_bucket_brigade *bb)
{
char *tag = NULL;
char *tag_val = NULL;
request_rec *r = f->r;
char *file = r->filename;
char parsed_string[MAX_STRING_LEN];
if (!ctx->argc) {
ap_log_rerror(APLOG_MARK,
(ctx->flags & SSI_FLAG_PRINTING)
? APLOG_ERR : APLOG_WARNING,
0, r, "missing argument for exec element in %s",
r->filename);
}
if (!(ctx->flags & SSI_FLAG_PRINTING)) {
return APR_SUCCESS;
}
if (!ctx->argc) {
SSI_CREATE_ERROR_BUCKET(ctx, f, bb);
return APR_SUCCESS;
}
if (ctx->flags & SSI_FLAG_NO_EXEC) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01228) "exec used but not allowed "
"in %s", r->filename);
SSI_CREATE_ERROR_BUCKET(ctx, f, bb);
return APR_SUCCESS;
}
while (1) {
cgi_pfn_gtv(ctx, &tag, &tag_val, SSI_VALUE_DECODED);
if (!tag || !tag_val) {
break;
}
if (!strcmp(tag, "cmd")) {
apr_status_t rv;
cgi_pfn_ps(ctx, tag_val, parsed_string, sizeof(parsed_string),
SSI_EXPAND_LEAVE_NAME);
rv = include_cmd(ctx, f, bb, parsed_string);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01229) "execution failure "
"for parameter \"%s\" to tag exec in file %s",
tag, r->filename);
SSI_CREATE_ERROR_BUCKET(ctx, f, bb);
break;
}
}
else if (!strcmp(tag, "cgi")) {
apr_status_t rv;
cgi_pfn_ps(ctx, tag_val, parsed_string, sizeof(parsed_string),
SSI_EXPAND_DROP_NAME);
rv = include_cgi(ctx, f, bb, parsed_string);
if (rv != APR_SUCCESS) {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01230) "invalid CGI ref "
"\"%s\" in %s", tag_val, file);
SSI_CREATE_ERROR_BUCKET(ctx, f, bb);
break;
}
}
else {
ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01231) "unknown parameter "
"\"%s\" to tag exec in %s", tag, file);
SSI_CREATE_ERROR_BUCKET(ctx, f, bb);
break;
}
}
return APR_SUCCESS;
}
/*============================================================================
*============================================================================
* This is the end of the cgi filter code moved from mod_include.
*============================================================================
*============================================================================*/
static int cgi_post_config(apr_pool_t *p, apr_pool_t *plog,
apr_pool_t *ptemp, server_rec *s)
{
cgi_pfn_reg_with_ssi = APR_RETRIEVE_OPTIONAL_FN(ap_register_include_handler);
cgi_pfn_gtv = APR_RETRIEVE_OPTIONAL_FN(ap_ssi_get_tag_and_value);
cgi_pfn_ps = APR_RETRIEVE_OPTIONAL_FN(ap_ssi_parse_string);
if ((cgi_pfn_reg_with_ssi) && (cgi_pfn_gtv) && (cgi_pfn_ps)) {
/* Required by mod_include filter. This is how mod_cgi registers
* with mod_include to provide processing of the exec directive.
*/
cgi_pfn_reg_with_ssi("exec", handle_exec);
}
/* This is the means by which unusual (non-unix) os's may find alternate
* means to run a given command (e.g. shebang/registry parsing on Win32)
*/
cgi_build_command = APR_RETRIEVE_OPTIONAL_FN(ap_cgi_build_command);
if (!cgi_build_command) {
cgi_build_command = default_build_command;
}
return OK;
}
static void register_hooks(apr_pool_t *p)
{
static const char * const aszPre[] = { "mod_include.c", NULL };
ap_hook_handler(cgi_handler, NULL, NULL, APR_HOOK_MIDDLE);
ap_hook_post_config(cgi_post_config, aszPre, NULL, APR_HOOK_REALLY_FIRST);
}
AP_DECLARE_MODULE(cgi) =
{
STANDARD20_MODULE_STUFF,
NULL, /* dir config creater */
NULL, /* dir merger --- default is to override */
create_cgi_config, /* server config */
merge_cgi_config, /* merge server config */
cgi_cmds, /* command apr_table_t */
register_hooks /* register hooks */
};