1 files changed, 577 insertions, 0 deletions
diff --git a/source3/lib/interface.c b/source3/lib/interface.c
new file mode 100644
index 0000000000..2e7c2706a0
--- /dev/null
+++ b/source3/lib/interface.c
@@ -0,0 +1,577 @@
+/*
+   Unix SMB/CIFS implementation.
+   multiple interface handling
+   Copyright (C) Andrew Tridgell 1992-1998
+   Copyright (C) Jeremy Allison 2007
+
+   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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+static struct iface_struct *probed_ifaces;
+static int total_probed;
+
+static struct interface *local_interfaces;
+
+/****************************************************************************
+ Check if an IP is one of mine.
+**************************************************************************/
+
+bool ismyaddr(const struct sockaddr_storage *ip)
+{
+	struct interface *i;
+	for (i=local_interfaces;i;i=i->next) {
+		if (addr_equal(&i->ip,ip)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+bool ismyip_v4(struct in_addr ip)
+{
+	struct sockaddr_storage ss;
+	in_addr_to_sockaddr_storage(&ss, ip);
+	return ismyaddr(&ss);
+}
+
+/****************************************************************************
+ Try and find an interface that matches an ip. If we cannot, return NULL.
+**************************************************************************/
+
+static struct interface *iface_find(const struct sockaddr_storage *ip,
+				bool check_mask)
+{
+	struct interface *i;
+
+	if (is_address_any(ip)) {
+		return local_interfaces;
+	}
+
+	for (i=local_interfaces;i;i=i->next) {
+		if (check_mask) {
+			if (same_net(ip, &i->ip, &i->netmask)) {
+				return i;
+			}
+		} else if (addr_equal(&i->ip, ip)) {
+			return i;
+		}
+	}
+
+	return NULL;
+}
+
+/****************************************************************************
+ Check if a packet is from a local (known) net.
+**************************************************************************/
+
+bool is_local_net(const struct sockaddr_storage *from)
+{
+	struct interface *i;
+	for (i=local_interfaces;i;i=i->next) {
+		if (same_net(from, &i->ip, &i->netmask)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+#if defined(HAVE_IPV6)
+void setup_linklocal_scope_id(struct sockaddr_storage *pss)
+{
+	struct interface *i;
+	for (i=local_interfaces;i;i=i->next) {
+		if (addr_equal(&i->ip,pss)) {
+			struct sockaddr_in6 *psa6 =
+				(struct sockaddr_in6 *)pss;
+			psa6->sin6_scope_id = if_nametoindex(i->name);
+			return;
+		}
+	}
+}
+#endif
+
+/****************************************************************************
+ Check if a packet is from a local (known) net.
+**************************************************************************/
+
+bool is_local_net_v4(struct in_addr from)
+{
+	struct sockaddr_storage ss;
+
+	in_addr_to_sockaddr_storage(&ss, from);
+	return is_local_net(&ss);
+}
+
+/****************************************************************************
+ How many interfaces do we have ?
+**************************************************************************/
+
+int iface_count(void)
+{
+	int ret = 0;
+	struct interface *i;
+
+	for (i=local_interfaces;i;i=i->next) {
+		ret++;
+	}
+	return ret;
+}
+
+/****************************************************************************
+ How many non-loopback IPv4 interfaces do we have ?
+**************************************************************************/
+
+int iface_count_v4_nl(void)
+{
+	int ret = 0;
+	struct interface *i;
+
+	for (i=local_interfaces;i;i=i->next) {
+		if (is_loopback_addr(&i->ip)) {
+			continue;
+		}
+		if (i->ip.ss_family == AF_INET) {
+			ret++;
+		}
+	}
+	return ret;
+}
+
+/****************************************************************************
+ Return a pointer to the in_addr of the first IPv4 interface.
+**************************************************************************/
+
+const struct in_addr *first_ipv4_iface(void)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i ;i=i->next) {
+		if (i->ip.ss_family == AF_INET) {
+			break;
+		}
+	}
+
+	if (!i) {
+		return NULL;
+	}
+	return &((const struct sockaddr_in *)&i->ip)->sin_addr;
+}
+
+/****************************************************************************
+ Return the Nth interface.
+**************************************************************************/
+
+struct interface *get_interface(int n)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i && n;i=i->next) {
+		n--;
+	}
+
+	if (i) {
+		return i;
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Return IP sockaddr_storage of the Nth interface.
+**************************************************************************/
+
+const struct sockaddr_storage *iface_n_sockaddr_storage(int n)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i && n;i=i->next) {
+		n--;
+	}
+
+	if (i) {
+		return &i->ip;
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Return IPv4 of the Nth interface (if a v4 address). NULL otherwise.
+**************************************************************************/
+
+const struct in_addr *iface_n_ip_v4(int n)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i && n;i=i->next) {
+		n--;
+	}
+
+	if (i && i->ip.ss_family == AF_INET) {
+		return &((const struct sockaddr_in *)&i->ip)->sin_addr;
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Return IPv4 bcast of the Nth interface (if a v4 address). NULL otherwise.
+**************************************************************************/
+
+const struct in_addr *iface_n_bcast_v4(int n)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i && n;i=i->next) {
+		n--;
+	}
+
+	if (i && i->ip.ss_family == AF_INET) {
+		return &((const struct sockaddr_in *)&i->bcast)->sin_addr;
+	}
+	return NULL;
+}
+
+/****************************************************************************
+ Return bcast of the Nth interface.
+**************************************************************************/
+
+const struct sockaddr_storage *iface_n_bcast(int n)
+{
+	struct interface *i;
+
+	for (i=local_interfaces;i && n;i=i->next) {
+		n--;
+	}
+
+	if (i) {
+		return &i->bcast;
+	}
+	return NULL;
+}
+
+/* these 3 functions return the ip/bcast/nmask for the interface
+   most appropriate for the given ip address. If they can't find
+   an appropriate interface they return the requested field of the
+   first known interface. */
+
+const struct sockaddr_storage *iface_ip(const struct sockaddr_storage *ip)
+{
+	struct interface *i = iface_find(ip, true);
+	if (i) {
+		return &i->ip;
+	}
+
+	/* Search for the first interface with
+	 * matching address family. */
+
+	for (i=local_interfaces;i;i=i->next) {
+		if (i->ip.ss_family == ip->ss_family) {
+			return &i->ip;
+		}
+	}
+	return NULL;
+}
+
+/*
+  return True if a IP is directly reachable on one of our interfaces
+*/
+
+bool iface_local(const struct sockaddr_storage *ip)
+{
+	return iface_find(ip, True) ? true : false;
+}
+
+/****************************************************************************
+ Add an interface to the linked list of interfaces.
+****************************************************************************/
+
+static void add_interface(const struct iface_struct *ifs)
+{
+	char addr[INET6_ADDRSTRLEN];
+	struct interface *iface;
+
+	if (iface_find(&ifs->ip, False)) {
+		DEBUG(3,("add_interface: not adding duplicate interface %s\n",
+			print_sockaddr(addr, sizeof(addr), &ifs->ip) ));
+		return;
+	}
+
+	if (!(ifs->flags & (IFF_BROADCAST|IFF_LOOPBACK))) {
+		DEBUG(3,("not adding non-broadcast interface %s\n",
+					ifs->name ));
+		return;
+	}
+
+	iface = SMB_MALLOC_P(struct interface);
+	if (!iface) {
+		return;
+	}
+
+	ZERO_STRUCTPN(iface);
+
+	iface->name = SMB_STRDUP(ifs->name);
+	if (!iface->name) {
+		SAFE_FREE(iface);
+		return;
+	}
+	iface->flags = ifs->flags;
+	iface->ip = ifs->ip;
+	iface->netmask = ifs->netmask;
+	iface->bcast = ifs->bcast;
+
+	DLIST_ADD(local_interfaces, iface);
+
+	DEBUG(2,("added interface %s ip=%s ",
+		iface->name,
+		print_sockaddr(addr, sizeof(addr), &iface->ip) ));
+	DEBUG(2,("bcast=%s ",
+		print_sockaddr(addr, sizeof(addr),
+			&iface->bcast) ));
+	DEBUG(2,("netmask=%s\n",
+		print_sockaddr(addr, sizeof(addr),
+			&iface->netmask) ));
+}
+
+/****************************************************************************
+ Interpret a single element from a interfaces= config line.
+
+ This handles the following different forms:
+
+ 1) wildcard interface name
+ 2) DNS name
+ 3) IP/masklen
+ 4) ip/mask
+ 5) bcast/mask
+****************************************************************************/
+
+static void interpret_interface(char *token)
+{
+	struct sockaddr_storage ss;
+	struct sockaddr_storage ss_mask;
+	struct sockaddr_storage ss_net;
+	struct sockaddr_storage ss_bcast;
+	struct iface_struct ifs;
+	char *p;
+	int i;
+	bool added=false;
+	bool goodaddr = false;
+
+	/* first check if it is an interface name */
+	for (i=0;i<total_probed;i++) {
+		if (gen_fnmatch(token, probed_ifaces[i].name) == 0) {
+			add_interface(&probed_ifaces[i]);
+			added = true;
+		}
+	}
+	if (added) {
+		return;
+	}
+
+	/* maybe it is a DNS name */
+	p = strchr_m(token,'/');
+	if (p == NULL) {
+		if (!interpret_string_addr(&ss, token, 0)) {
+			DEBUG(2, ("interpret_interface: Can't find address "
+				  "for %s\n", token));
+			return;
+		}
+
+		for (i=0;i<total_probed;i++) {
+			if (addr_equal(&ss, &probed_ifaces[i].ip)) {
+				add_interface(&probed_ifaces[i]);
+				return;
+			}
+		}
+		DEBUG(2,("interpret_interface: "
+			"can't determine interface for %s\n",
+			token));
+		return;
+	}
+
+	/* parse it into an IP address/netmasklength pair */
+	*p = 0;
+	goodaddr = interpret_string_addr(&ss, token, 0);
+	*p++ = '/';
+
+	if (!goodaddr) {
+		DEBUG(2,("interpret_interface: "
+			"can't determine interface for %s\n",
+			token));
+		return;
+	}
+
+	if (strlen(p) > 2) {
+		goodaddr = interpret_string_addr(&ss_mask, p, 0);
+		if (!goodaddr) {
+			DEBUG(2,("interpret_interface: "
+				"can't determine netmask from %s\n",
+				p));
+			return;
+		}
+	} else {
+		char *endp = NULL;
+		unsigned long val = strtoul(p, &endp, 0);
+		if (p == endp || (endp && *endp != '\0')) {
+			DEBUG(2,("interpret_interface: "
+				"can't determine netmask value from %s\n",
+				p));
+			return;
+		}
+		if (!make_netmask(&ss_mask, &ss, val)) {
+			DEBUG(2,("interpret_interface: "
+				"can't apply netmask value %lu from %s\n",
+				val,
+				p));
+			return;
+		}
+	}
+
+	make_bcast(&ss_bcast, &ss, &ss_mask);
+	make_net(&ss_net, &ss, &ss_mask);
+
+	/* Maybe the first component was a broadcast address. */
+	if (addr_equal(&ss_bcast, &ss) || addr_equal(&ss_net, &ss)) {
+		for (i=0;i<total_probed;i++) {
+			if (same_net(&ss, &probed_ifaces[i].ip, &ss_mask)) {
+				/* Temporarily replace netmask on
+				 * the detected interface - user knows
+				 * best.... */
+				struct sockaddr_storage saved_mask =
+					probed_ifaces[i].netmask;
+				probed_ifaces[i].netmask = ss_mask;
+				DEBUG(2,("interpret_interface: "
+					"using netmask value %s from "
+					"config file on interface %s\n",
+					p,
+					probed_ifaces[i].name));
+				add_interface(&probed_ifaces[i]);
+				probed_ifaces[i].netmask = saved_mask;
+				return;
+			}
+		}
+		DEBUG(2,("interpret_interface: Can't determine ip for "
+			"broadcast address %s\n",
+			token));
+		return;
+	}
+
+	/* Just fake up the interface definition. User knows best. */
+
+	DEBUG(2,("interpret_interface: Adding interface %s\n",
+		token));
+
+	ZERO_STRUCT(ifs);
+	(void)strlcpy(ifs.name, token, sizeof(ifs.name));
+	ifs.flags = IFF_BROADCAST;
+	ifs.ip = ss;
+	ifs.netmask = ss_mask;
+	ifs.bcast = ss_bcast;
+	add_interface(&ifs);
+}
+
+/****************************************************************************
+ Load the list of network interfaces.
+****************************************************************************/
+
+void load_interfaces(void)
+{
+	struct iface_struct ifaces[MAX_INTERFACES];
+	const char **ptr = lp_interfaces();
+	int i;
+
+	SAFE_FREE(probed_ifaces);
+
+	/* dump the current interfaces if any */
+	while (local_interfaces) {
+		struct interface *iface = local_interfaces;
+		DLIST_REMOVE(local_interfaces, local_interfaces);
+		SAFE_FREE(iface->name);
+		SAFE_FREE(iface);
+	}
+
+	/* Probe the kernel for interfaces */
+	total_probed = get_interfaces(ifaces, MAX_INTERFACES);
+
+	if (total_probed > 0) {
+		probed_ifaces = (struct iface_struct *)memdup(ifaces,
+				sizeof(ifaces[0])*total_probed);
+		if (!probed_ifaces) {
+			DEBUG(0,("ERROR: memdup failed\n"));
+			exit(1);
+		}
+	}
+
+	/* if we don't have a interfaces line then use all broadcast capable
+	   interfaces except loopback */
+	if (!ptr || !*ptr || !**ptr) {
+		if (total_probed <= 0) {
+			DEBUG(0,("ERROR: Could not determine network "
+			"interfaces, you must use a interfaces config line\n"));
+			exit(1);
+		}
+		for (i=0;i<total_probed;i++) {
+			if (probed_ifaces[i].flags & IFF_BROADCAST) {
+				add_interface(&probed_ifaces[i]);
+			}
+		}
+		return;
+	}
+
+	if (ptr) {
+		while (*ptr) {
+			char *ptr_cpy = SMB_STRDUP(*ptr);
+			if (ptr_cpy) {
+				interpret_interface(ptr_cpy);
+				free(ptr_cpy);
+			}
+			ptr++;
+		}
+	}
+
+	if (!local_interfaces) {
+		DEBUG(0,("WARNING: no network interfaces found\n"));
+	}
+}
+
+
+void gfree_interfaces(void)
+{
+	while (local_interfaces) {
+		struct interface *iface = local_interfaces;
+		DLIST_REMOVE(local_interfaces, local_interfaces);
+		SAFE_FREE(iface->name);
+		SAFE_FREE(iface);
+	}
+
+	SAFE_FREE(probed_ifaces);
+}
+
+/****************************************************************************
+ Return True if the list of probed interfaces has changed.
+****************************************************************************/
+
+bool interfaces_changed(void)
+{
+	int n;
+	struct iface_struct ifaces[MAX_INTERFACES];
+
+	n = get_interfaces(ifaces, MAX_INTERFACES);
+
+	if ((n > 0 )&& (n != total_probed ||
+			memcmp(ifaces, probed_ifaces, sizeof(ifaces[0])*n))) {
+		return true;
+	}
+
+	return false;
+}