Get mod_cgid to use apr calls for creating the actual CGI process. (3a32d979) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP Apache Httpd

CHANGES

+6 −0

Original line number	Diff line number	Diff line
		Changes with Apache 2.0b1

		*) Get mod_cgid to use apr calls for creating the actual CGI process.
		This also allows mod_cgid to use ap_os_create_priviledged_process,
		thus allowing for SuExec execution from mod_cgid. Currently, we do
		not support everything that standard SuExec supports, but at least
		it works minimally now. [Ryan Bloom]

		*) Allow SuExec to be configured from the ./configure command line.
		[Ryan Bloom]

modules/generators/mod_cgid.c

+53 −64

Original line number	Diff line number	Diff line
		@@ -203,31 +203,6 @@ static char *create_argv(apr_pool_t p, char path, char user, char *group,
		return av;
		}

		static int call_exec(request_rec r, char argv0, char **env, int shellcmd)
		{
		int pid = 0;
		int errfileno = STDERR_FILENO;
		/* the fd on r->server->error_log is closed, but we need somewhere to
		* put the error messages from the log_* functions. So, we use stderr,
		* since that is better than allowing errors to go unnoticed.
		*/
		apr_put_os_file(&r->server->error_log, &errfileno, r->pool);
		if (shellcmd) {
		execle(SHELL_PATH, SHELL_PATH, "-c", argv0, NULL, env);
		}

		else if ((!r->args) \|\| (!r->args[0]) \|\| strchr(r->args, '=')) {
		execle(r->filename, argv0, NULL, env);
		}

		else {
		execve(r->filename,
		create_argv(r->pool, NULL, NULL, NULL, argv0, r->args),
		env);
		}
		return (pid);
		}

		static void cgid_maint(int reason, void *data, apr_wait_t status)
		{
		#if APR_HAS_OTHER_CHILD
		@@ -319,6 +294,12 @@ static void get_req(int fd, request_rec r, char filename, char *argv0, char
		#endif
		dconf[i] = (void *)temp_core;
		r->per_dir_config = dconf;

		/* For right now, just make the notes table. At some point we will need
		* to actually fill this out, but for now we just don't want suexec to
		* seg fault.
		*/
		r->notes = apr_make_table(r->pool, 1);
		}


		@@ -397,30 +378,10 @@ static void send_req(int fd, request_rec r, char argv0, char **env)
		#endif
		}

		static void cgid_server_child(int sd)
		{
		char *argv0;
		char *filename;
		char **env;
		apr_pool_t *p;
		request_rec *r;

		apr_create_pool(&p, pcgi);
		r = apr_pcalloc(p, sizeof(request_rec));
		r->pool = p;
		dup2(sd, STDIN_FILENO);
		dup2(sd, STDOUT_FILENO);
		get_req(sd, r, &filename, &argv0, &env);
		call_exec(r, argv0, env, 0);
		exit(-1); /* We should NEVER get here */
		}

		static int cgid_server(void *data)
		{
		struct sockaddr_un unix_addr;
		int pid;
		int sd, sd2, rc;
		int errfile;
		mode_t omask;
		apr_socklen_t len;
		server_rec *main_server = data;
		@@ -473,6 +434,18 @@ static int cgid_server(void *data)
		unixd_setup_child(); /* if running as root, switch to configured user/group */

		while (1) {
		int errfileno = STDERR_FILENO;
		char *argv0;
		char *filename;
		char **env;
		const char * const *argv;
		apr_pool_t *p;
		request_rec *r;
		apr_procattr_t *procattr = NULL;
		apr_proc_t *procnew = NULL;
		apr_file_t *inout = NULL;


		len = sizeof(unix_addr);
		sd2 = accept(sd, (struct sockaddr *)&unix_addr, &len);
		if (sd2 < 0) {
		@@ -484,26 +457,42 @@ static int cgid_server(void *data)
		continue;
		}

		if ((pid = fork()) > 0) {
		close(sd2);
		}
		else if (pid == 0) {
		/* setup the STDERR here, because I have all the info
		* for it. I'll do the STDIN and STDOUT later, but I can't
		* do STDERR as easily.
		*/
		if (sconf->logname) {
		dup2(open(sconf->logname, O_WRONLY), STDERR_FILENO);
		apr_create_pool(&p, pcgi);

		r = apr_pcalloc(p, sizeof(request_rec));
		procnew = apr_pcalloc(p, sizeof(*procnew));
		r->pool = p;
		get_req(sd2, r, &filename, &argv0, &env);
		apr_put_os_file(&r->server->error_log, &errfileno, r->pool);
		apr_put_os_file(&inout, &sd2, r->pool);

		if (((rc = apr_createprocattr_init(&procattr, p)) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_io(procattr,
		APR_CHILD_BLOCK,
		APR_CHILD_BLOCK,
		APR_CHILD_BLOCK)) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_childin(procattr, inout, NULL)) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_childout(procattr, inout, NULL)) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_childerr(procattr, r->server->error_log, NULL)) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_dir(procattr,
		ap_make_dirstr_parent(r->pool, r->filename))) != APR_SUCCESS) \|\|
		((rc = apr_setprocattr_cmdtype(procattr, APR_PROGRAM)) != APR_SUCCESS)) {
		/* Something bad happened, tell the world. */
		ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r,
		"couldn't set child process attributes: %s", r->filename);
		}
		else {
		apr_get_os_file(&errfile, main_server->error_log);
		dup2(errfile, STDERR_FILENO);
		}
		cgid_server_child(sd2);
		argv = (const char * const *)create_argv(r->pool, NULL, NULL, NULL, argv0, r->args);
		rc = ap_os_create_privileged_process(r, procnew, argv0, argv,
		(const char * const *)env,
		procattr, p);

		close(sd2);
		if (rc != APR_SUCCESS) {
		/* Bad things happened. Everyone should have cleaned up. */
		ap_log_rerror(APLOG_MARK, APLOG_ERR, rc, r,
		"couldn't create child process: %d: %s", rc, r->filename);
		}
		else {
		ap_log_error(APLOG_MARK, APLOG_ERR, errno, (server_rec *)data,
		"Couldn't fork cgi script");
		}
		}
		return -1;