-/* -*- c-file-style: "linux" -*-
-
- rsync -- fast file replication program
-
- Copyright (C) 1992-2001 by Andrew Tridgell <tridge@samba.org>
- Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org>
-
- 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.
-*/
-
-/**
- * @file clientname.c
- *
+/*
* Functions for looking up the remote name or addr of a socket.
*
+ * Copyright (C) 1992-2001 Andrew Tridgell <tridge@samba.org>
+ * Copyright (C) 2001, 2002 Martin Pool <mbp@samba.org>
+ * Copyright (C) 2002-2009 Wayne Davison
+ *
+ * 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 3 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, visit the http://fsf.org website.
+ */
+
+/*
* This file is now converted to use the new-style getaddrinfo()
* interface, which supports IPv6 but is also supported on recent
* IPv4-only machines. On systems that don't have that interface, we
* emulate it using the KAME implementation.
- **/
+ */
#include "rsync.h"
static const char default_name[] = "UNKNOWN";
+extern int am_server;
/**
- * Return the IP addr of the client as a string
+ * Return the IP addr of the client as a string
**/
char *client_addr(int fd)
{
- struct sockaddr_storage ss;
- socklen_t length = sizeof ss;
static char addr_buf[100];
static int initialised;
+ struct sockaddr_storage ss;
+ socklen_t length = sizeof ss;
+ char *ssh_info, *p;
- if (initialised) return addr_buf;
+ if (initialised)
+ return addr_buf;
initialised = 1;
- client_sockaddr(fd, &ss, &length);
+ if (am_server) { /* daemon over --rsh mode */
+ strlcpy(addr_buf, "0.0.0.0", sizeof addr_buf);
+ if ((ssh_info = getenv("SSH_CONNECTION")) != NULL
+ || (ssh_info = getenv("SSH_CLIENT")) != NULL
+ || (ssh_info = getenv("SSH2_CLIENT")) != NULL) {
+ strlcpy(addr_buf, ssh_info, sizeof addr_buf);
+ /* Truncate the value to just the IP address. */
+ if ((p = strchr(addr_buf, ' ')) != NULL)
+ *p = '\0';
+ }
+ } else {
+ client_sockaddr(fd, &ss, &length);
+ getnameinfo((struct sockaddr *)&ss, length,
+ addr_buf, sizeof addr_buf, NULL, 0, NI_NUMERICHOST);
+ }
- getnameinfo((struct sockaddr *)&ss, length,
- addr_buf, sizeof(addr_buf), NULL, 0, NI_NUMERICHOST);
-
return addr_buf;
}
* If anything goes wrong, including the name->addr->name check, then
* we just use "UNKNOWN", so you can use that value in hosts allow
* lines.
+ *
+ * After translation from sockaddr to name we do a forward lookup to
+ * make sure nobody is spoofing PTR records.
**/
char *client_name(int fd)
{
- struct sockaddr_storage ss;
- socklen_t ss_len = sizeof ss;
static char name_buf[100];
static char port_buf[100];
static int initialised;
+ struct sockaddr_storage ss;
+ socklen_t ss_len;
- if (initialised) return name_buf;
+ if (initialised)
+ return name_buf;
- strcpy(name_buf, default_name);
+ strlcpy(name_buf, default_name, sizeof name_buf);
initialised = 1;
- client_sockaddr(fd, &ss, &ss_len);
+ memset(&ss, 0, sizeof ss);
+
+ if (am_server) { /* daemon over --rsh mode */
+ char *addr = client_addr(fd);
+ struct addrinfo hint, *answer;
+ int err;
+
+ if (strcmp(addr, "0.0.0.0") == 0)
+ return name_buf;
- if (!lookup_name(fd, &ss, ss_len, name_buf, sizeof name_buf, port_buf, sizeof port_buf))
- check_name(fd, &ss, ss_len, name_buf, port_buf);
+ memset(&hint, 0, sizeof hint);
+
+#ifdef AI_NUMERICHOST
+ hint.ai_flags = AI_NUMERICHOST;
+#endif
+ hint.ai_socktype = SOCK_STREAM;
+
+ if ((err = getaddrinfo(addr, NULL, &hint, &answer)) != 0) {
+ rprintf(FLOG, "malformed address %s: %s\n",
+ addr, gai_strerror(err));
+ return name_buf;
+ }
+
+ switch (answer->ai_family) {
+ case AF_INET:
+ ss_len = sizeof (struct sockaddr_in);
+ memcpy(&ss, answer->ai_addr, ss_len);
+ break;
+#ifdef INET6
+ case AF_INET6:
+ ss_len = sizeof (struct sockaddr_in6);
+ memcpy(&ss, answer->ai_addr, ss_len);
+ break;
+#endif
+ default:
+ exit_cleanup(RERR_SOCKETIO);
+ }
+ freeaddrinfo(answer);
+ } else {
+ ss_len = sizeof ss;
+ client_sockaddr(fd, &ss, &ss_len);
+ }
+
+ if (lookup_name(fd, &ss, ss_len, name_buf, sizeof name_buf,
+ port_buf, sizeof port_buf) == 0)
+ check_name(fd, &ss, name_buf, sizeof name_buf);
return name_buf;
}
/**
- * Get the sockaddr for the client.
+ * Get the sockaddr for the client.
+ *
+ * If it comes in as an ipv4 address mapped into IPv6 format then we
+ * convert it back to a regular IPv4.
**/
void client_sockaddr(int fd,
struct sockaddr_storage *ss,
socklen_t *ss_len)
{
+ memset(ss, 0, sizeof *ss);
+
if (getpeername(fd, (struct sockaddr *) ss, ss_len)) {
/* FIXME: Can we really not continue? */
- rprintf(FERROR, RSYNC_NAME ": getpeername on fd%d failed: %s\n",
- fd, strerror(errno));
+ rsyserr(FLOG, errno, "getpeername on fd%d failed", fd);
exit_cleanup(RERR_SOCKETIO);
}
#ifdef INET6
- if (get_sockaddr_family(ss) == AF_INET6 &&
+ if (get_sockaddr_family(ss) == AF_INET6 &&
IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)ss)->sin6_addr)) {
/* OK, so ss is in the IPv6 family, but it is really
* an IPv4 address: something like
struct sockaddr_in6 sin6;
struct sockaddr_in *sin;
- memcpy(&sin6, ss, sizeof(sin6));
+ memcpy(&sin6, ss, sizeof sin6);
sin = (struct sockaddr_in *)ss;
- memset(sin, 0, sizeof(*sin));
+ memset(sin, 0, sizeof *sin);
sin->sin_family = AF_INET;
- *ss_len = sizeof(struct sockaddr_in);
-#ifdef HAVE_SOCKADDR_LEN
+ *ss_len = sizeof (struct sockaddr_in);
+#ifdef HAVE_SOCKADDR_IN_LEN
sin->sin_len = *ss_len;
#endif
sin->sin_port = sin6.sin6_port;
* (IN6_V4MAPPED_TO_SINADDR ?), but it does not seem
* to be present in the Linux headers. */
memcpy(&sin->sin_addr, &sin6.sin6_addr.s6_addr[12],
- sizeof(sin->sin_addr));
- }
+ sizeof sin->sin_addr);
+ }
#endif
}
/**
* Look up a name from @p ss into @p name_buf.
+ *
+ * @param fd file descriptor for client socket.
**/
int lookup_name(int fd, const struct sockaddr_storage *ss,
socklen_t ss_len,
- char *name_buf, size_t name_buf_len,
- char *port_buf, size_t port_buf_len)
+ char *name_buf, size_t name_buf_size,
+ char *port_buf, size_t port_buf_size)
{
int name_err;
-
+
/* reverse lookup */
name_err = getnameinfo((struct sockaddr *) ss, ss_len,
- name_buf, name_buf_len,
- port_buf, port_buf_len,
+ name_buf, name_buf_size,
+ port_buf, port_buf_size,
NI_NAMEREQD | NI_NUMERICSERV);
if (name_err != 0) {
- strcpy(name_buf, default_name);
- rprintf(FERROR, RSYNC_NAME ": name lookup failed for %s: %s\n",
- client_addr(fd),
- gai_strerror(name_err));
+ strlcpy(name_buf, default_name, name_buf_size);
+ rprintf(FLOG, "name lookup failed for %s: %s\n",
+ client_addr(fd), gai_strerror(name_err));
return name_err;
}
-/* Do a forward lookup on name_buf and make sure it corresponds to ss
- * -- otherwise we may be being spoofed. If we suspect we are, then
- * we don't abort the connection but just emit a warning. */
+/**
+ * Compare an addrinfo from the resolver to a sockinfo.
+ *
+ * Like strcmp, returns 0 for identical.
+ **/
+int compare_addrinfo_sockaddr(const struct addrinfo *ai,
+ const struct sockaddr_storage *ss)
+{
+ int ss_family = get_sockaddr_family(ss);
+ const char fn[] = "compare_addrinfo_sockaddr";
+
+ if (ai->ai_family != ss_family) {
+ rprintf(FLOG, "%s: response family %d != %d\n",
+ fn, ai->ai_family, ss_family);
+ return 1;
+ }
+
+ /* The comparison method depends on the particular AF. */
+ if (ss_family == AF_INET) {
+ const struct sockaddr_in *sin1, *sin2;
+
+ sin1 = (const struct sockaddr_in *) ss;
+ sin2 = (const struct sockaddr_in *) ai->ai_addr;
+
+ return memcmp(&sin1->sin_addr, &sin2->sin_addr,
+ sizeof sin1->sin_addr);
+ }
+
+#ifdef INET6
+ if (ss_family == AF_INET6) {
+ const struct sockaddr_in6 *sin1, *sin2;
+
+ sin1 = (const struct sockaddr_in6 *) ss;
+ sin2 = (const struct sockaddr_in6 *) ai->ai_addr;
+
+ if (ai->ai_addrlen < sizeof (struct sockaddr_in6)) {
+ rprintf(FLOG, "%s: too short sockaddr_in6; length=%d\n",
+ fn, (int)ai->ai_addrlen);
+ return 1;
+ }
+
+ if (memcmp(&sin1->sin6_addr, &sin2->sin6_addr,
+ sizeof sin1->sin6_addr))
+ return 1;
+
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ if (sin1->sin6_scope_id != sin2->sin6_scope_id)
+ return 1;
+#endif
+ return 0;
+ }
+#endif /* INET6 */
+
+ /* don't know */
+ return 1;
+}
+
+
+/**
+ * Do a forward lookup on @p name_buf and make sure it corresponds to
+ * @p ss -- otherwise we may be being spoofed. If we suspect we are,
+ * then we don't abort the connection but just emit a warning, and
+ * change @p name_buf to be "UNKNOWN".
+ *
+ * We don't do anything with the service when checking the name,
+ * because it doesn't seem that it could be spoofed in any way, and
+ * getaddrinfo on random service names seems to cause problems on AIX.
+ **/
int check_name(int fd,
const struct sockaddr_storage *ss,
- socklen_t ss_len,
- char *name_buf,
- const char *port_buf)
+ char *name_buf, size_t name_buf_size)
{
struct addrinfo hints, *res, *res0;
int error;
int ss_family = get_sockaddr_family(ss);
- memset(&hints, 0, sizeof(hints));
- hints.ai_family = PF_UNSPEC;
- hints.ai_flags = ss_family;
+ memset(&hints, 0, sizeof hints);
+ hints.ai_family = ss_family;
+ hints.ai_flags = AI_CANONNAME;
hints.ai_socktype = SOCK_STREAM;
- error = getaddrinfo(name_buf, port_buf, &hints, &res0);
+ error = getaddrinfo(name_buf, NULL, &hints, &res0);
if (error) {
- rprintf(FERROR,
- RSYNC_NAME ": forward name lookup for %s:%s failed: %s\n",
- name_buf, port_buf,
- gai_strerror(error));
- strcpy(name_buf, default_name);
+ rprintf(FLOG, "forward name lookup for %s failed: %s\n",
+ name_buf, gai_strerror(error));
+ strlcpy(name_buf, default_name, name_buf_size);
return error;
}
-
- /* We expect that one of the results will be the same as ss. */
+ /* Given all these results, we expect that one of them will be
+ * the same as ss. The comparison is a bit complicated. */
for (res = res0; res; res = res->ai_next) {
- if (res->ai_family != ss_family) {
- rprintf(FERROR,
- "check_name: response family %d != %d\n",
- res->ai_family, ss_family);
- continue;
- }
- if (res->ai_addrlen != ss_len) {
- rprintf(FERROR,
- "check_name: addrlen %d != %d\n",
- res->ai_addrlen, ss_len);
- continue;
- }
- if (memcmp(res->ai_addr, ss, res->ai_addrlen) == 0) {
- rprintf(FERROR,
- "check_name: %d bytes of address identical\n",
- res->ai_addrlen);
- break;
- } else{
- rprintf(FERROR,
- "check_name: %d bytes of address NOT identical\n",
- res->ai_addrlen);
- }
+ if (!compare_addrinfo_sockaddr(res, ss))
+ break; /* OK, identical */
}
if (!res0) {
/* We hit the end of the list without finding an
* address that was the same as ss. */
- rprintf(FERROR, RSYNC_NAME
- ": no known address for \"%s\": "
- "spoofed address?\n",
- name_buf);
- strcpy(name_buf, default_name);
- }
- if (res == NULL) {
+ rprintf(FLOG, "no known address for \"%s\": "
+ "spoofed address?\n", name_buf);
+ strlcpy(name_buf, default_name, name_buf_size);
+ } else if (res == NULL) {
/* We hit the end of the list without finding an
* address that was the same as ss. */
- rprintf(FERROR, RSYNC_NAME
- ": %s is not a known address for \"%s\": "
- "spoofed address?\n",
- client_addr(fd),
- name_buf);
- strcpy(name_buf, default_name);
+ rprintf(FLOG, "%s is not a known address for \"%s\": "
+ "spoofed address?\n", client_addr(fd), name_buf);
+ strlcpy(name_buf, default_name, name_buf_size);
}
freeaddrinfo(res0);
return 0;
}
-
git.samba.org / rsync.git / blobdiff