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-rw-r--r--source3/lib/socket_wrapper.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/source3/lib/socket_wrapper.c b/source3/lib/socket_wrapper.c
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--- /dev/null
+++ b/source3/lib/socket_wrapper.c
@@ -0,0 +1,467 @@
+/*
+ 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.
+*/
+
+#ifdef _SAMBA_BUILD
+#include "includes.h"
+#include "system/network.h"
+#else
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <errno.h>
+#include <sys/un.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include "dlinklist.h"
+#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
+
+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 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 = 1025; /* Default to 1025 */
+ p = strchr(un->sun_path, '/');
+ if (p) p++; else p = un->sun_path;
+
+ if (sscanf(p, "sock_ip_%d_%u", &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(int type, const struct sockaddr_in *in, struct sockaddr_un *un)
+{
+ uint16_t prt = ntohs(in->sin_port);
+ snprintf(un->sun_path, sizeof(un->sun_path), "%s/sock_ip_%d_%u",
+ getenv("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(const 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->type, (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 (!getenv("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);
+ }
+
+ 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;
+
+ if (addr && addrlen) {
+ child_si->myname_len = *addrlen;
+ child_si->myname = sockaddr_dup(addr, *addrlen);
+ }
+
+ return fd;
+}
+
+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;
+ }
+
+ 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);
+ }
+
+ 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->myname_len = addrlen;
+ si->myname = sockaddr_dup(myaddr, addrlen);
+ 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);
+ }
+
+ 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);
+ }
+
+ /* using sendto() on an unbound DGRAM socket would give the
+ recipient no way to reply, as unlike UDP, a unix domain socket
+ can't auto-assign emphemeral port numbers, so we need to assign
+ it here */
+ if (si->bound == 0 && si->type == SOCK_DGRAM) {
+ 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/sock_ip_%u_%u", getenv("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;
+ }
+ }
+
+
+ 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);
+}