src/server/shttpd/cgi.c - third_party/openwsman - Git at Google

 /*
  * Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
  * All rights reserved
  *
  * "THE BEER-WARE LICENSE" (Revision 42):
  * Sergey Lyubka wrote this file.  As long as you retain this notice you
  * can do whatever you want with this stuff. If we meet some day, and you think
  * this stuff is worth it, you can buy me a beer in return.
  */

 #include "shttpd_defs.h"

 #if !defined(NO_CGI)
 struct env_block {
 	char	buf[ENV_MAX];		/* Environment buffer		*/
 	int	len;			/* Space taken			*/
 	char	*vars[CGI_ENV_VARS];	/* Point into the buffer	*/
 	int	nvars;			/* Number of variables		*/
 };

 /*
  * UNIX socketpair() implementation. Why? Because Windows does not have it.
  * Return 0 on success, -1 on error.
  */
 static int
 my_socketpair(struct conn *c, int sp[2])
 {


 #ifdef ENABLE_IPV6
 	struct sockaddr_in6	sa;
 #else
 	struct sockaddr_in      sa;
 #endif
 	int			sock = -1, ret = -1;
 	socklen_t		len = sizeof(sa);

 	(void) memset(&sa, 0, sizeof(sa));
 #ifdef ENABLE_IPV6
 	sa.sin6_family          = AF_INET6;
         sa.sin6_addr		= in6addr_loopback;
 	sa.sin6_port           	= htons(0);

 #else
 	sa.sin_family           = AF_INET;
 	sa.sin_addr.s_addr      = htonl(INADDR_LOOPBACK);
 	sa.sin_port             = htons(0);
 #endif

 #ifdef ENABLE_IPV6
 	 if (!wsmand_options_get_use_ipv6()
 	     || (sock = socket(AF_INET6, SOCK_STREAM, 0)) == -1) {
 		if(!wsmand_options_get_use_ipv4()
 		   || (sock = socket(AF_INET,SOCK_STREAM,0)) == -1)
 	                elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
         }

 #else
 	if ((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
 		elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
 	}

 #endif
 	else if (bind(sock, (struct sockaddr *) &sa, len) != 0) {
 		elog(E_LOG, c, "mysocketpair: bind(): %d", ERRNO);
 		(void) closesocket(sock);
 	} else if (listen(sock, 1) != 0) {
 		elog(E_LOG, c, "mysocketpair: listen(): %d", ERRNO);
 		(void) closesocket(sock);
 	} else if (getsockname(sock, (struct sockaddr *) &sa, &len) != 0) {
 		elog(E_LOG, c, "mysocketpair: getsockname(): %d", ERRNO);
 		(void) closesocket(sock);
 	}

 #ifdef ENABLE_IPV6
 	else if ((sp[0] = socket(AF_INET6, SOCK_STREAM, 6)) == -1) {
                 elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
                 (void) closesocket(sock);
         }
 #else
 	else if ((sp[0] = socket(AF_INET, SOCK_STREAM, 6)) == -1) {
 		elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
 		(void) closesocket(sock);
 	}
 #endif

 	else if (connect(sp[0], (struct sockaddr *) &sa, len) != 0) {
 		elog(E_LOG, c, "mysocketpair: connect(): %d", ERRNO);
 		(void) closesocket(sock);
 		(void) closesocket(sp[0]);
 	} else if ((sp[1] = accept(sock,(struct sockaddr *) &sa, &len)) == -1) {
 		elog(E_LOG, c, "mysocketpair: accept(): %d", ERRNO);
 		(void) closesocket(sock);
 		(void) closesocket(sp[0]);
 	} else {
 		/* Success */
 		ret = 0;
 		(void) closesocket(sock);
 	}

 #ifndef _WIN32
 	(void) fcntl(sp[0], F_SETFD, FD_CLOEXEC);
 	(void) fcntl(sp[1], F_SETFD, FD_CLOEXEC);
 #endif /* _WIN32*/

 	return (ret);
 }

 static void
 addenv(struct env_block *block, const char *fmt, ...)
 {
 	int	n, space;
 	va_list	ap;

 	space = sizeof(block->buf) - block->len - 2;
 	assert(space >= 0);

 	va_start(ap, fmt);
 	n = vsnprintf(block->buf + block->len, space, fmt, ap);
 	va_end(ap);

 	if (n > 0 && n < space && block->nvars < CGI_ENV_VARS - 2) {
 		block->vars[block->nvars++] = block->buf + block->len;
 		block->len += n + 1;	/* Include \0 terminator */
 	}
 }

 static void
 add_http_headers_to_env(struct env_block *b, const char *s, int len)
 {
 	const char	*p, *v, *e = s + len;
 	int		space, n, i, ch;

 	/* Loop through all headers in the request */
 	while (s < e) {

 		/* Find where this header ends. Remember where value starts */
 		for (p = s, v = NULL; p < e && *p != '\n'; p++)
 			if (v == NULL && *p == ':')
 				v = p;

 		/* 2 null terminators and "HTTP_" */
 		space = (sizeof(b->buf) - b->len) - (2 + 5);
 		assert(space >= 0);

 		/* Copy header if enough space in the environment block */
 		if (v > s && p > v + 2 && space > p - s) {

 			/* Store var */
 			if (b->nvars < (int) NELEMS(b->vars) - 1)
 				b->vars[b->nvars++] = b->buf + b->len;

 			(void) memcpy(b->buf + b->len, "HTTP_", 5);
 			b->len += 5;

 			/* Copy header name. Substitute '-' to '_' */
 			n = v - s;
 			for (i = 0; i < n; i++) {
 				ch = s[i] == '-' ? '_' : s[i];
 				b->buf[b->len++] = toupper(ch);
 			}

 			b->buf[b->len++] = '=';

 			/* Copy header value */
 			v += 2;
 			n = p[-1] == '\r' ? (p - v) - 1 : p - v;
 			for (i = 0; i < n; i++)
 				b->buf[b->len++] = v[i];

 			/* Null-terminate */
 			b->buf[b->len++] = '\0';
 		}

 		s = p + 1;	/* Shift to the next header */
 	}
 }

 static void
 prepare_environment(const struct conn *c, const char *prog,
 		struct env_block *blk)
 {
 	const struct headers	*h = &c->ch;
 	const char		*s;
 	size_t			len;

 	blk->len = blk->nvars = 0;

 	/* Prepare the environment block */
 	addenv(blk, "%s", "GATEWAY_INTERFACE=CGI/1.1");
 	addenv(blk, "%s", "SERVER_PROTOCOL=HTTP/1.1");
 	addenv(blk, "%s", "REDIRECT_STATUS=200");	/* PHP */
 	addenv(blk, "SERVER_PORT=%d", c->loc_port);
 	addenv(blk, "SERVER_NAME=%s", c->ctx->auth_realm);
 	addenv(blk, "SERVER_ROOT=%s", c->ctx->document_root);
 	addenv(blk, "DOCUMENT_ROOT=%s", c->ctx->document_root);
 	addenv(blk, "REQUEST_METHOD=%s", known_http_methods[c->method].ptr);
 #ifdef ENABLE_IPV6
 	if (wsmand_options_get_use_ipv6()) {
 		char str[INET6_ADDRSTRLEN];
 		inet_ntop( AF_INET6,&c->sa.u.sin.sin6_addr, str, sizeof(str));
 		addenv(blk, "REMOTE_ADDR=%s", str);
 		addenv(blk, "REMOTE_PORT=%hu", ntohs(c->sa.u.sin.sin6_port));
 	}
 	else {
 #endif
 		addenv(blk, "REMOTE_ADDR=%s", inet_ntoa(c->sa.u.sin.sin_addr));
 		addenv(blk, "REMOTE_PORT=%hu", ntohs(c->sa.u.sin.sin_port));
 #ifdef ENABLE_IPV6
 	}
 #endif

 	addenv(blk, "REQUEST_URI=%s", c->uri);
 	addenv(blk, "SCRIPT_NAME=%s", prog + strlen(c->ctx->document_root));
 	addenv(blk, "SCRIPT_FILENAME=%s", prog);	/* PHP */
 	addenv(blk, "PATH_TRANSLATED=%s", prog);

 	if (h->ct.v_vec.len > 0)
 		addenv(blk, "CONTENT_TYPE=%.*s",
 		    h->ct.v_vec.len, h->ct.v_vec.ptr);

 	if (c->query != NULL)
 		addenv(blk, "QUERY_STRING=%s", c->query);

 	if (c->path_info != NULL)
 		addenv(blk, "PATH_INFO=/%s", c->path_info);

 	if (h->cl.v_big_int > 0)
 		addenv(blk, "CONTENT_LENGTH=%lu", h->cl.v_big_int);

 	if ((s = getenv("PATH")) != NULL)
 		addenv(blk, "PATH=%s", s);

 #ifdef _WIN32
 	if ((s = getenv("COMSPEC")) != NULL)
 		addenv(blk, "COMSPEC=%s", s);
 	if ((s = getenv("SYSTEMROOT")) != NULL)
 		addenv(blk, "SYSTEMROOT=%s", s);
 #else
 	if ((s = getenv("LD_LIBRARY_PATH")) != NULL)
 		addenv(blk, "LD_LIBRARY_PATH=%s", s);
 #endif /* _WIN32 */

 	if ((s = getenv("PERLLIB")) != NULL)
 		addenv(blk, "PERLLIB=%s", s);

 	if (h->user.v_vec.len > 0) {
 		addenv(blk, "REMOTE_USER=%.*s",
 		    h->user.v_vec.len, h->user.v_vec.ptr);
 		addenv(blk, "%s", "AUTH_TYPE=Digest");
 	}

 	/* Add user-specified variables */
 	s = c->ctx->cgi_vars;
 	FOR_EACH_WORD_IN_LIST(s, len)
 		addenv(blk, "%.*s", len, s);

 	/* Add all headers as HTTP_* variables */
 	add_http_headers_to_env(blk, c->headers,
 	    c->rem.headers_len - (c->headers - c->request));

 	blk->vars[blk->nvars++] = NULL;
 	blk->buf[blk->len++] = '\0';

 	assert(blk->nvars < CGI_ENV_VARS);
 	assert(blk->len > 0);
 	assert(blk->len < (int) sizeof(blk->buf));

 	/* Debug stuff to view passed environment */
 	DBG(("%s: %d vars, %d env size", prog, blk->nvars, blk->len));
 	{
 		int i;
 		for (i = 0 ; i < blk->nvars; i++)
 			DBG(("[%s]", blk->vars[i] ? blk->vars[i] : "null"));
 	}
 }

 int
 run_cgi(struct conn *c, const char *prog)
 {
 	struct env_block	blk;
 	char			dir[FILENAME_MAX], *p;
 	int			ret, pair[2];

 	prepare_environment(c, prog, &blk);
 	pair[0] = pair[1] = -1;

 	/* CGI must be executed in its own directory */
 	(void) snprintf(dir, sizeof(dir), "%s", prog);
 	for (p = dir + strlen(dir) - 1; p > dir; p--)
 		if (*p == '/') {
 			*p++ = '\0';
 			break;
 		}

 	if (my_socketpair(c, pair) != 0) {
 		ret = -1;
 	} else if (spawn_process(c, prog, blk.buf, blk.vars, pair[1], dir)) {
 		ret = -1;
 		(void) closesocket(pair[0]);
 		(void) closesocket(pair[1]);
 	} else {
 		ret = 0;
 		c->loc.chan.sock = pair[0];
 	}

 	return (ret);
 }

 void
 do_cgi(struct conn *c)
 {
 	DBG(("running CGI: [%s]", c->uri));
 	assert(c->loc.io.size > CGI_REPLY_LEN);
 	memcpy(c->loc.io.buf, CGI_REPLY, CGI_REPLY_LEN);
 	c->loc.io.head = c->loc.io.tail = c->loc.io.total = CGI_REPLY_LEN;
 	c->loc.io_class = &io_cgi;
 	c->loc.flags = FLAG_R;
 	if (c->method == METHOD_POST)
 		c->loc.flags |= FLAG_W;
 }

 #endif /* !NO_CGI */
	/*
	* Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
	* All rights reserved
	*
	* "THE BEER-WARE LICENSE" (Revision 42):
	* Sergey Lyubka wrote this file. As long as you retain this notice you
	* can do whatever you want with this stuff. If we meet some day, and you think
	* this stuff is worth it, you can buy me a beer in return.
	*/

	#include "shttpd_defs.h"

	#if !defined(NO_CGI)
	struct env_block {
	char buf[ENV_MAX]; /* Environment buffer */
	int len; /* Space taken */
	char vars[CGI_ENV_VARS]; / Point into the buffer */
	int nvars; /* Number of variables */
	};

	/*
	* UNIX socketpair() implementation. Why? Because Windows does not have it.
	* Return 0 on success, -1 on error.
	*/
	static int
	my_socketpair(struct conn *c, int sp[2])
	{


	#ifdef ENABLE_IPV6
	struct sockaddr_in6 sa;
	#else
	struct sockaddr_in sa;
	#endif
	int sock = -1, ret = -1;
	socklen_t len = sizeof(sa);

	(void) memset(&sa, 0, sizeof(sa));
	#ifdef ENABLE_IPV6
	sa.sin6_family = AF_INET6;
	sa.sin6_addr = in6addr_loopback;
	sa.sin6_port = htons(0);

	#else
	sa.sin_family = AF_INET;
	sa.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
	sa.sin_port = htons(0);
	#endif

	#ifdef ENABLE_IPV6
	if (!wsmand_options_get_use_ipv6()
	\|\| (sock = socket(AF_INET6, SOCK_STREAM, 0)) == -1) {
	if(!wsmand_options_get_use_ipv4()
	\|\| (sock = socket(AF_INET,SOCK_STREAM,0)) == -1)
	elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
	}

	#else
	if ((sock = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
	elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
	}

	#endif
	else if (bind(sock, (struct sockaddr *) &sa, len) != 0) {
	elog(E_LOG, c, "mysocketpair: bind(): %d", ERRNO);
	(void) closesocket(sock);
	} else if (listen(sock, 1) != 0) {
	elog(E_LOG, c, "mysocketpair: listen(): %d", ERRNO);
	(void) closesocket(sock);
	} else if (getsockname(sock, (struct sockaddr *) &sa, &len) != 0) {
	elog(E_LOG, c, "mysocketpair: getsockname(): %d", ERRNO);
	(void) closesocket(sock);
	}

	#ifdef ENABLE_IPV6
	else if ((sp[0] = socket(AF_INET6, SOCK_STREAM, 6)) == -1) {
	elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
	(void) closesocket(sock);
	}
	#else
	else if ((sp[0] = socket(AF_INET, SOCK_STREAM, 6)) == -1) {
	elog(E_LOG, c, "mysocketpair: socket(): %d", ERRNO);
	(void) closesocket(sock);
	}
	#endif

	else if (connect(sp[0], (struct sockaddr *) &sa, len) != 0) {
	elog(E_LOG, c, "mysocketpair: connect(): %d", ERRNO);
	(void) closesocket(sock);
	(void) closesocket(sp[0]);
	} else if ((sp[1] = accept(sock,(struct sockaddr *) &sa, &len)) == -1) {
	elog(E_LOG, c, "mysocketpair: accept(): %d", ERRNO);
	(void) closesocket(sock);
	(void) closesocket(sp[0]);
	} else {
	/* Success */
	ret = 0;
	(void) closesocket(sock);
	}

	#ifndef _WIN32
	(void) fcntl(sp[0], F_SETFD, FD_CLOEXEC);
	(void) fcntl(sp[1], F_SETFD, FD_CLOEXEC);
	#endif /* _WIN32*/

	return (ret);
	}

	static void
	addenv(struct env_block block, const char fmt, ...)
	{
	int n, space;
	va_list ap;

	space = sizeof(block->buf) - block->len - 2;
	assert(space >= 0);

	va_start(ap, fmt);
	n = vsnprintf(block->buf + block->len, space, fmt, ap);
	va_end(ap);

	if (n > 0 && n < space && block->nvars < CGI_ENV_VARS - 2) {
	block->vars[block->nvars++] = block->buf + block->len;
	block->len += n + 1; /* Include \0 terminator */
	}
	}

	static void
	add_http_headers_to_env(struct env_block b, const char s, int len)
	{
	const char p, v, *e = s + len;
	int space, n, i, ch;

	/* Loop through all headers in the request */
	while (s < e) {

	/* Find where this header ends. Remember where value starts */
	for (p = s, v = NULL; p < e && *p != '\n'; p++)
	if (v == NULL && *p == ':')
	v = p;

	/* 2 null terminators and "HTTP_" */
	space = (sizeof(b->buf) - b->len) - (2 + 5);
	assert(space >= 0);

	/* Copy header if enough space in the environment block */
	if (v > s && p > v + 2 && space > p - s) {

	/* Store var */
	if (b->nvars < (int) NELEMS(b->vars) - 1)
	b->vars[b->nvars++] = b->buf + b->len;

	(void) memcpy(b->buf + b->len, "HTTP_", 5);
	b->len += 5;

	/* Copy header name. Substitute '-' to '_' */
	n = v - s;
	for (i = 0; i < n; i++) {
	ch = s[i] == '-' ? '_' : s[i];
	b->buf[b->len++] = toupper(ch);
	}

	b->buf[b->len++] = '=';

	/* Copy header value */
	v += 2;
	n = p[-1] == '\r' ? (p - v) - 1 : p - v;
	for (i = 0; i < n; i++)
	b->buf[b->len++] = v[i];

	/* Null-terminate */
	b->buf[b->len++] = '\0';
	}

	s = p + 1; /* Shift to the next header */
	}
	}

	static void
	prepare_environment(const struct conn c, const char prog,
	struct env_block *blk)
	{
	const struct headers *h = &c->ch;
	const char *s;
	size_t len;

	blk->len = blk->nvars = 0;

	/* Prepare the environment block */
	addenv(blk, "%s", "GATEWAY_INTERFACE=CGI/1.1");
	addenv(blk, "%s", "SERVER_PROTOCOL=HTTP/1.1");
	addenv(blk, "%s", "REDIRECT_STATUS=200"); /* PHP */
	addenv(blk, "SERVER_PORT=%d", c->loc_port);
	addenv(blk, "SERVER_NAME=%s", c->ctx->auth_realm);
	addenv(blk, "SERVER_ROOT=%s", c->ctx->document_root);
	addenv(blk, "DOCUMENT_ROOT=%s", c->ctx->document_root);
	addenv(blk, "REQUEST_METHOD=%s", known_http_methods[c->method].ptr);
	#ifdef ENABLE_IPV6
	if (wsmand_options_get_use_ipv6()) {
	char str[INET6_ADDRSTRLEN];
	inet_ntop( AF_INET6,&c->sa.u.sin.sin6_addr, str, sizeof(str));
	addenv(blk, "REMOTE_ADDR=%s", str);
	addenv(blk, "REMOTE_PORT=%hu", ntohs(c->sa.u.sin.sin6_port));
	}
	else {
	#endif
	addenv(blk, "REMOTE_ADDR=%s", inet_ntoa(c->sa.u.sin.sin_addr));
	addenv(blk, "REMOTE_PORT=%hu", ntohs(c->sa.u.sin.sin_port));
	#ifdef ENABLE_IPV6
	}
	#endif

	addenv(blk, "REQUEST_URI=%s", c->uri);
	addenv(blk, "SCRIPT_NAME=%s", prog + strlen(c->ctx->document_root));
	addenv(blk, "SCRIPT_FILENAME=%s", prog); /* PHP */
	addenv(blk, "PATH_TRANSLATED=%s", prog);

	if (h->ct.v_vec.len > 0)
	addenv(blk, "CONTENT_TYPE=%.*s",
	h->ct.v_vec.len, h->ct.v_vec.ptr);

	if (c->query != NULL)
	addenv(blk, "QUERY_STRING=%s", c->query);

	if (c->path_info != NULL)
	addenv(blk, "PATH_INFO=/%s", c->path_info);

	if (h->cl.v_big_int > 0)
	addenv(blk, "CONTENT_LENGTH=%lu", h->cl.v_big_int);

	if ((s = getenv("PATH")) != NULL)
	addenv(blk, "PATH=%s", s);

	#ifdef _WIN32
	if ((s = getenv("COMSPEC")) != NULL)
	addenv(blk, "COMSPEC=%s", s);
	if ((s = getenv("SYSTEMROOT")) != NULL)
	addenv(blk, "SYSTEMROOT=%s", s);
	#else
	if ((s = getenv("LD_LIBRARY_PATH")) != NULL)
	addenv(blk, "LD_LIBRARY_PATH=%s", s);
	#endif /* _WIN32 */

	if ((s = getenv("PERLLIB")) != NULL)
	addenv(blk, "PERLLIB=%s", s);

	if (h->user.v_vec.len > 0) {
	addenv(blk, "REMOTE_USER=%.*s",
	h->user.v_vec.len, h->user.v_vec.ptr);
	addenv(blk, "%s", "AUTH_TYPE=Digest");
	}

	/* Add user-specified variables */
	s = c->ctx->cgi_vars;
	FOR_EACH_WORD_IN_LIST(s, len)
	addenv(blk, "%.*s", len, s);

	/* Add all headers as HTTP_* variables */
	add_http_headers_to_env(blk, c->headers,
	c->rem.headers_len - (c->headers - c->request));

	blk->vars[blk->nvars++] = NULL;
	blk->buf[blk->len++] = '\0';

	assert(blk->nvars < CGI_ENV_VARS);
	assert(blk->len > 0);
	assert(blk->len < (int) sizeof(blk->buf));

	/* Debug stuff to view passed environment */
	DBG(("%s: %d vars, %d env size", prog, blk->nvars, blk->len));
	{
	int i;
	for (i = 0 ; i < blk->nvars; i++)
	DBG(("[%s]", blk->vars[i] ? blk->vars[i] : "null"));
	}
	}

	int
	run_cgi(struct conn c, const char prog)
	{
	struct env_block blk;
	char dir[FILENAME_MAX], *p;
	int ret, pair[2];

	prepare_environment(c, prog, &blk);
	pair[0] = pair[1] = -1;

	/* CGI must be executed in its own directory */
	(void) snprintf(dir, sizeof(dir), "%s", prog);
	for (p = dir + strlen(dir) - 1; p > dir; p--)
	if (*p == '/') {
	*p++ = '\0';
	break;
	}

	if (my_socketpair(c, pair) != 0) {
	ret = -1;
	} else if (spawn_process(c, prog, blk.buf, blk.vars, pair[1], dir)) {
	ret = -1;
	(void) closesocket(pair[0]);
	(void) closesocket(pair[1]);
	} else {
	ret = 0;
	c->loc.chan.sock = pair[0];
	}

	return (ret);
	}

	void
	do_cgi(struct conn *c)
	{
	DBG(("running CGI: [%s]", c->uri));
	assert(c->loc.io.size > CGI_REPLY_LEN);
	memcpy(c->loc.io.buf, CGI_REPLY, CGI_REPLY_LEN);
	c->loc.io.head = c->loc.io.tail = c->loc.io.total = CGI_REPLY_LEN;
	c->loc.io_class = &io_cgi;
	c->loc.flags = FLAG_R;
	if (c->method == METHOD_POST)
	c->loc.flags \|= FLAG_W;
	}

	#endif /* !NO_CGI */