/* -*- c-file-style: "linux" -*-
Copyright (C) 1992-2001 by Andrew Tridgell <tridge@samba.org>
- Copyright (C) 2001 by Martin Pool <mbp@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
* @file socket.c
*
* Socket functions used in rsync.
+ *
+ * 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"
-#ifndef HAVE_GETADDRINFO
-#include "lib/addrinfo.h"
-#endif
-
-// extern int af; /* NO MORE BLOODY GLOBALS! */
-
/* Establish a proxy connection on an open socket to a web roxy by
* using the CONNECT method. */
static int establish_proxy_connection(int fd, char *host, int port)
}
+/**
+ * Try to set the local address for a newly-created socket. Return -1
+ * if this fails.
+ **/
+int try_bind_local(int s,
+ int ai_family, int ai_socktype,
+ const char *bind_address)
+{
+ int error;
+ struct addrinfo bhints, *bres_all, *r;
+
+ memset(&bhints, 0, sizeof(bhints));
+ bhints.ai_family = ai_family;
+ bhints.ai_socktype = ai_socktype;
+ bhints.ai_flags = AI_PASSIVE;
+ if (getaddrinfo(bind_address, NULL, &bhints, &bres_all) == -1) {
+ rprintf(FERROR, RSYNC_NAME ": getaddrinfo %s: %s\n",
+ bind_address, gai_strerror(error));
+ return -1;
+ }
+
+ for (r = bres_all; r; r = r->ai_next) {
+ if (bind(s, r->ai_addr, r->ai_addrlen) == -1)
+ continue;
+ return s;
+ }
+
+ /* no error message; there might be some problem that allows
+ * creation of the socket but not binding, perhaps if the
+ * machine has no ipv6 address of this name. */
+ return -1;
+}
+
/**
* Open a socket to a tcp remote host with the specified port .
}
s = -1;
+ /* Try to connect to all addresses for this machine until we get
+ * through. It might e.g. be multi-homed, or have both IPv4 and IPv6
+ * addresses. We need to create a socket for each record, since the
+ * address record tells us what protocol to use to try to connect. */
for (res = res0; res; res = res->ai_next) {
s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (s < 0)
continue;
- if (bind_address) {
- struct addrinfo bhints, *bres;
-
- memset(&bhints, 0, sizeof(bhints));
- bhints.ai_family = res->ai_family;
- bhints.ai_socktype = type;
- bhints.ai_flags = AI_PASSIVE;
- error = getaddrinfo(bind_address, NULL, &bhints, &bres);
- if (error) {
- rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s <noport>: %s\n",
- bind_address, gai_strerror(error));
- continue;
- }
- if (bres->ai_next) {
- rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s resolved to multiple hosts\n",
- bind_address);
- freeaddrinfo(bres);
+ if (bind_address)
+ if (try_bind_local(s, res->ai_family, type,
+ bind_address) == -1) {
+ close(s);
+ s = -1;
continue;
}
- bind(s, bres->ai_addr, bres->ai_addrlen);
- }
if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
close(s);
/**
* Open a socket of the specified type, port and address for incoming data
*
+ * Try to be better about handling the results of getaddrinfo(): when
+ * opening an inbound socket, we might get several address results,
+ * e.g. for the machine's ipv4 and ipv6 name.
+ *
+ * If binding a wildcard, then any one of them should do. If an address
+ * was specified but it's insufficiently specific then that's not our
+ * fault.
+ *
+ * However, some of the advertized addresses may not work because e.g. we
+ * don't have IPv6 support in the kernel. In that case go on and try all
+ * addresses until one succeeds.
+ *
* @param bind_address Local address to bind, or NULL to allow it to
* default.
**/
{
int one=1;
int s;
- struct addrinfo hints, *res;
+ struct addrinfo hints, *all_ai, *resp;
char portbuf[10];
int error;
hints.ai_socktype = type;
hints.ai_flags = AI_PASSIVE;
snprintf(portbuf, sizeof(portbuf), "%d", port);
- error = getaddrinfo(bind_address, portbuf, &hints, &res);
+ error = getaddrinfo(bind_address, portbuf, &hints, &all_ai);
if (error) {
rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: %s\n",
bind_address, gai_strerror(error));
return -1;
}
- if (res->ai_next) {
- rprintf(FERROR, RSYNC_NAME ": getaddrinfo: bind address %s: "
- "resolved to multiple hosts\n",
- bind_address);
- freeaddrinfo(res);
- return -1;
- }
- s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
- if (s < 0) {
- rprintf(FERROR, RSYNC_NAME ": open socket in failed: %s\n",
- strerror(errno));
- freeaddrinfo(res);
- return -1;
- }
+ /* We may not be able to create the socket, if for example the
+ * machine knows about IPv6 in the C library, but not in the
+ * kernel. */
+ for (resp = all_ai; resp; resp = resp->ai_next) {
+ s = socket(resp->ai_family, resp->ai_socktype,
+ resp->ai_protocol);
- setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
-
- /* now we've got a socket - we need to bind it */
- if (bind(s, res->ai_addr, res->ai_addrlen) < 0) {
- rprintf(FERROR, RSYNC_NAME ": bind failed on port %d\n", port);
- freeaddrinfo(res);
- close(s);
- return -1;
+ if (s == -1)
+ /* See if there's another address that will work... */
+ continue;
+
+ setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
+ (char *)&one, sizeof one);
+
+ /* now we've got a socket - we need to bind it */
+ if (bind(s, all_ai->ai_addr, all_ai->ai_addrlen) < 0) {
+ /* Nope, try another */
+ close(s);
+ continue;
+ }
+
+ return s;
}
- return s;
+ rprintf(FERROR, RSYNC_NAME ": open inbound socket on port %d failed: "
+ "%s\n",
+ port,
+ strerror(errno));
+
+ freeaddrinfo(all_ai);
+ return -1;
}
{
int s;
extern char *bind_address;
+ extern int default_af_hint;
/* open an incoming socket */
- s = open_socket_in(SOCK_STREAM, port, bind_address,
- global_opts.af_hint);
+ s = open_socket_in(SOCK_STREAM, port, bind_address, default_af_hint);
if (s == -1)
exit_cleanup(RERR_SOCKETIO);
while (1) {
fd_set fds;
int fd;
- struct sockaddr addr;
- int in_addrlen = sizeof(addr);
+ struct sockaddr_storage addr;
+ int addrlen = sizeof(addr);
/* close log file before the potentially very long select so
file can be trimmed by another process instead of growing
if(!FD_ISSET(s, &fds)) continue;
- fd = accept(s,(struct sockaddr *)&addr,&in_addrlen);
+ fd = accept(s,(struct sockaddr *)&addr,&addrlen);
if (fd == -1) continue;
**/
char *client_addr(int fd)
{
- struct sockaddr ss;
+ struct sockaddr_storage ss;
int length = sizeof(ss);
static char addr_buf[100];
static int initialised;
initialised = 1;
- if (getpeername(fd, &ss, &length)) {
+ if (getpeername(fd, (struct sockaddr *)&ss, &length)) {
exit_cleanup(RERR_SOCKETIO);
}
- getnameinfo(&ss, length,
+ getnameinfo((struct sockaddr *)&ss, length,
addr_buf, sizeof(addr_buf), NULL, 0, NI_NUMERICHOST);
return addr_buf;
}
+static int get_sockaddr_family(const struct sockaddr_storage *ss)
+{
+ return ((struct sockaddr *) ss)->sa_family;
+}
+
+
/**
* Return the DNS name of the client
**/
char *client_name(int fd)
{
- struct sockaddr ss;
+ struct sockaddr_storage ss;
int length = sizeof(ss);
static char name_buf[100];
static char port_buf[100];
if (getpeername(fd, (struct sockaddr *)&ss, &length)) {
/* FIXME: Can we really not continue? */
rprintf(FERROR, RSYNC_NAME ": getpeername on fd%d failed: %s\n",
- strerror(errno));
+ fd, strerror(errno));
exit_cleanup(RERR_SOCKETIO);
}
#ifdef INET6
- if (ss.ss_family == 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
+ * "::ffff:10.130.1.2". If we use it as-is, then the
+ * reverse lookup might fail or perhaps something else
+ * bad might happen. So instead we convert it to an
+ * equivalent address in the IPv4 address family. */
struct sockaddr_in6 sin6;
struct sockaddr_in *sin;
sin->sin_len = length;
#endif
sin->sin_port = sin6.sin6_port;
+ /* FIXME: Isn't there a macro we can use here rather
+ * than grovelling through the struct? It might be
+ * wrong on some systems. */
memcpy(&sin->sin_addr, &sin6.sin6_addr.s6_addr[12],
sizeof(sin->sin_addr));
}
/* XXX sin6_flowinfo and other fields */
for (res = res0; res; res = res->ai_next) {
- if (res->ai_family != ss.sa_family)
+ if (res->ai_family != get_sockaddr_family(&ss))
continue;
if (res->ai_addrlen != length)
continue;
break;
}
- /* TODO: Do a forward lookup as well to prevent spoofing */
-
if (res == NULL) {
strcpy(name_buf, def);
rprintf(FERROR, RSYNC_NAME ": "
- "reverse name lookup mismatch on fd%d - spoofed address?\n",
- fd);
+ "reverse name lookup for \"%s\" failed on fd%d - spoofed address? \n",
+ name_buf, fd);
}
freeaddrinfo(res0);
return name_buf;
}
-/**
- * Convert a string to an IP address. The string can be a name or
- * dotted decimal number.
- *
- * Returns a pointer to a static in_addr struct -- if you call this
- * more than once then you should copy it.
- *
- * TODO: Use getaddrinfo() instead, or make this function call getnameinfo
- **/
-struct in_addr *ip_address(const char *str)
-{
- static struct in_addr ret;
- struct hostent *hp;
-
- if (!str) {
- rprintf (FERROR, "ip_address received NULL name\n");
- return NULL;
- }
-
- /* try as an IP address */
- if (inet_aton(str, &ret) != 0) {
- return &ret;
- }
-
- /* otherwise assume it's a network name of some sort and use
- gethostbyname */
- if ((hp = gethostbyname (str)) == 0) {
- rprintf(FERROR, "gethostbyname failed for \"%s\": unknown host?\n",str);
- return NULL;
- }
-
- if (hp->h_addr == NULL) {
- rprintf(FERROR, "gethostbyname: host address is invalid for host \"%s\"\n",str);
- return NULL;
- }
-
- if (hp->h_length > sizeof ret) {
- rprintf(FERROR, "gethostbyname: host address for \"%s\" is too large\n",
- str);
- return NULL;
- }
-
- if (hp->h_addrtype != AF_INET) {
- rprintf (FERROR, "gethostname: host address for \"%s\" is not IPv4\n",
- str);
- return NULL;
- }
-
- /* This is kind of difficult. The only field in ret is
- s_addr, which is the IP address as a 32-bit int. On
- UNICOS, s_addr is in fact a *bitfield* for reasons best
- know to Cray. This means we can't memcpy in to it. On the
- other hand, h_addr is a char*, so we can't just assign.
-
- Since there's meant to be only one field inside the in_addr
- structure we will try just copying over the top and see how
- that goes. */
- memcpy (&ret, hp->h_addr, hp->h_length);
-
- return &ret;
-}
-
-
/*******************************************************************
this is like socketpair but uses tcp. It is used by the Samba