X-Git-Url: http://git.maemo.org/git/?p=samba;a=blobdiff_plain;f=source%2Flib%2Fsocket_wrapper.c;fp=source%2Flib%2Fsocket_wrapper.c;h=9d65aa923afa77f8c42d3150114392e9a6118df4;hp=0000000000000000000000000000000000000000;hb=6bca4ca307d55b6dc888e56cee47aebcddbce786;hpb=7fd70fa738b636089bcc6c961aa3eaa02f20dda2

diff --git a/source/lib/socket_wrapper.c b/source/lib/socket_wrapper.c
new file mode 100644
index 0000000..9d65aa9
--- /dev/null
+++ b/source/lib/socket_wrapper.c
@@ -0,0 +1,539 @@
+/* 
+   Socket wrapper library. Passes all socket communication over 
+   unix domain sockets if the environment variable SOCKET_WRAPPER_DIR 
+   is set.
+   Copyright (C) Jelmer Vernooij 2005
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+#ifdef SOCKET_WRAPPER_REPLACE
+#undef accept
+#undef connect
+#undef bind
+#undef getpeername
+#undef getsockname
+#undef getsockopt
+#undef setsockopt
+#undef recvfrom
+#undef sendto
+#undef socket
+#undef close
+#endif
+
+/* LD_PRELOAD doesn't work yet, so REWRITE_CALLS is all we support
+ * for now */
+#define REWRITE_CALLS 
+
+#ifdef REWRITE_CALLS
+#define real_accept accept
+#define real_connect connect
+#define real_bind bind
+#define real_getpeername getpeername
+#define real_getsockname getsockname
+#define real_getsockopt getsockopt
+#define real_setsockopt setsockopt
+#define real_recvfrom recvfrom
+#define real_sendto sendto
+#define real_socket socket
+#define real_close close
+#endif
+
+#undef malloc
+#undef calloc
+#undef strdup
+/* we need to use a very terse format here as IRIX 6.4 silently
+   truncates names to 16 chars, so if we use a longer name then we
+   can't tell which port a packet came from with recvfrom() 
+   
+   with this format we have 8 chars left for the directory name
+*/
+#define SOCKET_FORMAT "%u_%u"
+
+static struct sockaddr *sockaddr_dup(const void *data, socklen_t len)
+{
+	struct sockaddr *ret = (struct sockaddr *)malloc(len);
+	memcpy(ret, data, len);
+	return ret;
+}
+
+struct socket_info
+{
+	int fd;
+
+	int domain;
+	int type;
+	int protocol;
+	int bound;
+
+	char *path;
+	char *tmp_path;
+
+	struct sockaddr *myname;
+	socklen_t myname_len;
+
+	struct sockaddr *peername;
+	socklen_t peername_len;
+
+	struct socket_info *prev, *next;
+};
+
+static struct socket_info *sockets = NULL;
+
+
+static const char *socket_wrapper_dir(void)
+{
+	const char *s = getenv("SOCKET_WRAPPER_DIR");
+	if (s == NULL) {
+		return NULL;
+	}
+	if (strncmp(s, "./", 2) == 0) {
+		s += 2;
+	}
+	return s;
+}
+
+static int convert_un_in(const struct sockaddr_un *un, struct sockaddr_in *in, socklen_t *len)
+{
+	unsigned int prt;
+	const char *p;
+	int type;
+
+	if ((*len) < sizeof(struct sockaddr_in)) {
+		return 0;
+	}
+
+	in->sin_family = AF_INET;
+	in->sin_port = htons(1025); /* Default to 1025 */
+	p = strrchr(un->sun_path, '/');
+	if (p) p++; else p = un->sun_path;
+
+	if (sscanf(p, SOCKET_FORMAT, &type, &prt) == 2) {
+		in->sin_port = htons(prt);
+	}
+	in->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+	*len = sizeof(struct sockaddr_in);
+	return 0;
+}
+
+static int convert_in_un(struct socket_info *si, const struct sockaddr_in *in, struct sockaddr_un *un)
+{
+	int type = si->type;
+	uint16_t prt = ntohs(in->sin_port);
+	if (prt == 0) {
+		struct stat st;
+		/* handle auto-allocation of ephemeral ports */
+		prt = 5000;
+		do {
+			snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT, 
+				 socket_wrapper_dir(), type, ++prt);
+		} while (stat(un->sun_path, &st) == 0 && prt < 10000);
+		((struct sockaddr_in *)si->myname)->sin_port = htons(prt);
+	} 
+	snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT, 
+		 socket_wrapper_dir(), type, prt);
+	return 0;
+}
+
+static struct socket_info *find_socket_info(int fd)
+{
+	struct socket_info *i;
+	for (i = sockets; i; i = i->next) {
+		if (i->fd == fd) 
+			return i;
+	}
+
+	return NULL;
+}
+
+static int sockaddr_convert_to_un(struct socket_info *si, const struct sockaddr *in_addr, socklen_t in_len, 
+					 struct sockaddr_un *out_addr)
+{
+	if (!out_addr)
+		return 0;
+
+	out_addr->sun_family = AF_UNIX;
+
+	switch (in_addr->sa_family) {
+	case AF_INET:
+		return convert_in_un(si, (const struct sockaddr_in *)in_addr, out_addr);
+	case AF_UNIX:
+		memcpy(out_addr, in_addr, sizeof(*out_addr));
+		return 0;
+	default:
+		break;
+	}
+	
+	errno = EAFNOSUPPORT;
+	return -1;
+}
+
+static int sockaddr_convert_from_un(const struct socket_info *si, 
+				    const struct sockaddr_un *in_addr, 
+				    socklen_t un_addrlen,
+				    int family,
+				    struct sockaddr *out_addr,
+				    socklen_t *out_len)
+{
+	if (out_addr == NULL || out_len == NULL) 
+		return 0;
+
+	if (un_addrlen == 0) {
+		*out_len = 0;
+		return 0;
+	}
+
+	switch (family) {
+	case AF_INET:
+		return convert_un_in(in_addr, (struct sockaddr_in *)out_addr, out_len);
+	case AF_UNIX:
+		memcpy(out_addr, in_addr, sizeof(*in_addr));
+		*out_len = sizeof(*in_addr);
+		return 0;
+	default:
+		break;
+	}
+
+	errno = EAFNOSUPPORT;
+	return -1;
+}
+
+int swrap_socket(int domain, int type, int protocol)
+{
+	struct socket_info *si;
+	int fd;
+
+	if (!socket_wrapper_dir()) {
+		return real_socket(domain, type, protocol);
+	}
+	
+	fd = real_socket(AF_UNIX, type, 0);
+
+	if (fd == -1) return -1;
+
+	si = calloc(1, sizeof(struct socket_info));
+
+	si->domain = domain;
+	si->type = type;
+	si->protocol = protocol;
+	si->fd = fd;
+
+	DLIST_ADD(sockets, si);
+
+	return si->fd;
+}
+
+int swrap_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
+{
+	struct socket_info *parent_si, *child_si;
+	int fd;
+	socklen_t un_addrlen = sizeof(struct sockaddr_un);
+	struct sockaddr_un un_addr;
+	int ret;
+
+	parent_si = find_socket_info(s);
+	if (!parent_si) {
+		return real_accept(s, addr, addrlen);
+	}
+
+	memset(&un_addr, 0, sizeof(un_addr));
+
+	ret = real_accept(s, (struct sockaddr *)&un_addr, &un_addrlen);
+	if (ret == -1) return ret;
+
+	fd = ret;
+
+	ret = sockaddr_convert_from_un(parent_si, &un_addr, un_addrlen,
+				       parent_si->domain, addr, addrlen);
+	if (ret == -1) return ret;
+
+	child_si = malloc(sizeof(struct socket_info));
+	memset(child_si, 0, sizeof(*child_si));
+
+	child_si->fd = fd;
+	child_si->bound = 1;
+
+	child_si->myname_len = parent_si->myname_len;
+	child_si->myname = sockaddr_dup(parent_si->myname, parent_si->myname_len);
+
+	child_si->peername_len = *addrlen;
+	child_si->peername = sockaddr_dup(addr, *addrlen);
+
+	DLIST_ADD(sockets, child_si);
+
+	return fd;
+}
+
+/* using sendto() or connect() on an unbound socket would give the
+   recipient no way to reply, as unlike UDP and TCP, a unix domain
+   socket can't auto-assign emphemeral port numbers, so we need to
+   assign it here */
+static int swrap_auto_bind(struct socket_info *si)
+{
+	struct sockaddr_un un_addr;
+	struct sockaddr_in in;
+	int i;
+	
+	un_addr.sun_family = AF_UNIX;
+	
+	for (i=0;i<1000;i++) {
+		snprintf(un_addr.sun_path, sizeof(un_addr.sun_path), 
+			 "%s/"SOCKET_FORMAT, socket_wrapper_dir(),
+			 SOCK_DGRAM, i + 10000);
+		if (bind(si->fd, (struct sockaddr *)&un_addr, 
+			 sizeof(un_addr)) == 0) {
+			si->tmp_path = strdup(un_addr.sun_path);
+			si->bound = 1;
+			break;
+		}
+	}
+	if (i == 1000) {
+		return -1;
+	}
+	
+	memset(&in, 0, sizeof(in));
+	in.sin_family = AF_INET;
+	in.sin_port   = htons(i);
+	in.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+	
+	si->myname_len = sizeof(in);
+	si->myname = sockaddr_dup(&in, si->myname_len);
+	si->bound = 1;
+	return 0;
+}
+
+
+int swrap_connect(int s, const struct sockaddr *serv_addr, socklen_t addrlen)
+{
+	int ret;
+	struct sockaddr_un un_addr;
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_connect(s, serv_addr, addrlen);
+	}
+
+	/* only allow pseudo loopback connections */
+	if (serv_addr->sa_family == AF_INET &&
+		((const struct sockaddr_in *)serv_addr)->sin_addr.s_addr != 
+	    htonl(INADDR_LOOPBACK)) {
+		errno = ENETUNREACH;
+		return -1;
+	}
+
+	if (si->bound == 0 && si->domain != AF_UNIX) {
+		ret = swrap_auto_bind(si);
+		if (ret == -1) return -1;
+	}
+
+	ret = sockaddr_convert_to_un(si, (const struct sockaddr *)serv_addr, addrlen, &un_addr);
+	if (ret == -1) return -1;
+
+	ret = real_connect(s, (struct sockaddr *)&un_addr, 
+			   sizeof(struct sockaddr_un));
+
+	if (ret == 0) {
+		si->peername_len = addrlen;
+		si->peername = sockaddr_dup(serv_addr, addrlen);
+	}
+
+	return ret;
+}
+
+int swrap_bind(int s, const struct sockaddr *myaddr, socklen_t addrlen)
+{
+	int ret;
+	struct sockaddr_un un_addr;
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_bind(s, myaddr, addrlen);
+	}
+
+	si->myname_len = addrlen;
+	si->myname = sockaddr_dup(myaddr, addrlen);
+
+	if (myaddr->sa_family == AF_INET &&
+	    ((const struct sockaddr_in *)myaddr)->sin_addr.s_addr == 0) {
+		((struct sockaddr_in *)si->myname)->sin_addr.s_addr = 
+			htonl(INADDR_LOOPBACK);
+	}
+	ret = sockaddr_convert_to_un(si, (const struct sockaddr *)myaddr, addrlen, &un_addr);
+	if (ret == -1) return -1;
+
+	unlink(un_addr.sun_path);
+
+	ret = real_bind(s, (struct sockaddr *)&un_addr,
+			sizeof(struct sockaddr_un));
+
+	if (ret == 0) {
+		si->bound = 1;
+	}
+
+	return ret;
+}
+
+int swrap_getpeername(int s, struct sockaddr *name, socklen_t *addrlen)
+{
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_getpeername(s, name, addrlen);
+	}
+
+	if (!si->peername) 
+	{
+		errno = ENOTCONN;
+		return -1;
+	}
+
+	memcpy(name, si->peername, si->peername_len);
+	*addrlen = si->peername_len;
+
+	return 0;
+}
+
+int swrap_getsockname(int s, struct sockaddr *name, socklen_t *addrlen)
+{
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_getsockname(s, name, addrlen);
+	}
+
+	memcpy(name, si->myname, si->myname_len);
+	*addrlen = si->myname_len;
+
+	return 0;
+}
+
+int swrap_getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen)
+{
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_getsockopt(s, level, optname, optval, optlen);
+	}
+
+	if (level == SOL_SOCKET) {
+		return real_getsockopt(s, level, optname, optval, optlen);
+	} 
+
+	switch (si->domain) {
+	case AF_UNIX:
+		return real_getsockopt(s, level, optname, optval, optlen);
+	default:
+		errno = ENOPROTOOPT;
+		return -1;
+	}
+}
+
+int swrap_setsockopt(int s, int  level,  int  optname,  const  void  *optval, socklen_t optlen)
+{
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_setsockopt(s, level, optname, optval, optlen);
+	}
+
+	if (level == SOL_SOCKET) {
+		return real_setsockopt(s, level, optname, optval, optlen);
+	}
+
+	switch (si->domain) {
+	case AF_UNIX:
+		return real_setsockopt(s, level, optname, optval, optlen);
+	case AF_INET:
+		/* Silence some warnings */
+#ifdef TCP_NODELAY
+		if (optname == TCP_NODELAY) 
+			return 0;
+#endif
+	default:
+		errno = ENOPROTOOPT;
+		return -1;
+	}
+}
+
+ssize_t swrap_recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen)
+{
+	struct sockaddr_un un_addr;
+	socklen_t un_addrlen = sizeof(un_addr);
+	int ret;
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_recvfrom(s, buf, len, flags, from, fromlen);
+	}
+
+	/* irix 6.4 forgets to null terminate the sun_path string :-( */
+	memset(&un_addr, 0, sizeof(un_addr));
+	ret = real_recvfrom(s, buf, len, flags, (struct sockaddr *)&un_addr, &un_addrlen);
+	if (ret == -1) 
+		return ret;
+
+	if (sockaddr_convert_from_un(si, &un_addr, un_addrlen,
+				     si->domain, from, fromlen) == -1) {
+		return -1;
+	}
+	
+	return ret;
+}
+
+
+ssize_t swrap_sendto(int  s,  const  void *buf, size_t len, int flags, const struct sockaddr *to, socklen_t tolen)
+{
+	struct sockaddr_un un_addr;
+	int ret;
+	struct socket_info *si = find_socket_info(s);
+
+	if (!si) {
+		return real_sendto(s, buf, len, flags, to, tolen);
+	}
+
+	if (si->bound == 0 && si->domain != AF_UNIX) {
+		ret = swrap_auto_bind(si);
+		if (ret == -1) return -1;
+	}
+
+	ret = sockaddr_convert_to_un(si, to, tolen, &un_addr);
+	if (ret == -1) return -1;
+
+	ret = real_sendto(s, buf, len, flags, (struct sockaddr *)&un_addr, sizeof(un_addr));
+
+	return ret;
+}
+
+int swrap_close(int fd)
+{
+	struct socket_info *si = find_socket_info(fd);
+
+	if (si) {
+		DLIST_REMOVE(sockets, si);
+
+		free(si->path);
+		free(si->myname);
+		free(si->peername);
+		if (si->tmp_path) {
+			unlink(si->tmp_path);
+			free(si->tmp_path);
+		}
+		free(si);
+	}
+
+	return real_close(fd);
+}