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authorStefan Metzmacher <metze@samba.org>2006-08-17 13:37:04 +0000
committerGerald (Jerry) Carter <jerry@samba.org>2007-10-10 14:15:39 -0500
commita2eca9174c7803732658a1e6f7e8ed873c4fb6fd (patch)
tree237a5c57dd5b5b311ddc9830f48a7f9fa8401b38 /source4/lib/socket/interface.c
parent04b2dfd9350a218f61a2d83576ca9454e8cfed2b (diff)
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r17586: merge lib/netif into lib/socket and use -lnsl -lsocket on the
configure check for the interfaces. should fix the build on some old sun boxes metze (This used to be commit f20e251bfd9f1eb7ce5c00739631b1625a2aa467)
Diffstat (limited to 'source4/lib/socket/interface.c')
-rw-r--r--source4/lib/socket/interface.c354
1 files changed, 354 insertions, 0 deletions
diff --git a/source4/lib/socket/interface.c b/source4/lib/socket/interface.c
new file mode 100644
index 0000000000..5b2b4fd1ab
--- /dev/null
+++ b/source4/lib/socket/interface.c
@@ -0,0 +1,354 @@
+/*
+ Unix SMB/CIFS implementation.
+
+ multiple interface handling
+
+ Copyright (C) Andrew Tridgell 1992-2005
+
+ 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"
+#include "system/network.h"
+#include "lib/socket/netif.h"
+#include "dlinklist.h"
+
+/** used for network interfaces */
+struct interface {
+ struct interface *next, *prev;
+ struct ipv4_addr ip;
+ struct ipv4_addr nmask;
+ const char *ip_s;
+ const char *bcast_s;
+ const char *nmask_s;
+};
+
+static struct interface *local_interfaces;
+
+#define ALLONES ((uint32_t)0xFFFFFFFF)
+/*
+ address construction based on a patch from fred@datalync.com
+*/
+#define MKBCADDR(_IP, _NM) ((_IP & _NM) | (_NM ^ ALLONES))
+#define MKNETADDR(_IP, _NM) (_IP & _NM)
+
+static struct ipv4_addr tov4(struct in_addr in)
+{
+ struct ipv4_addr in2;
+ in2.addr = in.s_addr;
+ return in2;
+}
+
+/****************************************************************************
+Try and find an interface that matches an ip. If we cannot, return NULL
+ **************************************************************************/
+static struct interface *iface_find(struct in_addr ip, BOOL CheckMask)
+{
+ struct interface *i;
+ if (is_zero_ip(tov4(ip))) return local_interfaces;
+
+ for (i=local_interfaces;i;i=i->next)
+ if (CheckMask) {
+ if (same_net(i->ip,tov4(ip),i->nmask)) return i;
+ } else if (i->ip.addr == ip.s_addr) return i;
+
+ return NULL;
+}
+
+
+/****************************************************************************
+add an interface to the linked list of interfaces
+****************************************************************************/
+static void add_interface(struct in_addr ip, struct in_addr nmask)
+{
+ struct interface *iface;
+ struct ipv4_addr bcast;
+ if (iface_find(ip, False)) {
+ DEBUG(3,("not adding duplicate interface %s\n",inet_ntoa(ip)));
+ return;
+ }
+
+ iface = talloc(local_interfaces, struct interface);
+ if (!iface) return;
+
+ ZERO_STRUCTPN(iface);
+
+ iface->ip = tov4(ip);
+ iface->nmask = tov4(nmask);
+ bcast.addr = MKBCADDR(iface->ip.addr, iface->nmask.addr);
+
+ /* keep string versions too, to avoid people tripping over the implied
+ static in sys_inet_ntoa() */
+ iface->ip_s = talloc_strdup(iface, sys_inet_ntoa(iface->ip));
+ iface->nmask_s = talloc_strdup(iface, sys_inet_ntoa(iface->nmask));
+
+ if (nmask.s_addr != ~0) {
+ iface->bcast_s = talloc_strdup(iface, sys_inet_ntoa(bcast));
+ }
+
+ DLIST_ADD_END(local_interfaces, iface, struct interface *);
+
+ DEBUG(2,("added interface ip=%s nmask=%s\n", iface->ip_s, iface->nmask_s));
+}
+
+
+
+/**
+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(const char *token,
+ struct iface_struct *probed_ifaces,
+ int total_probed)
+{
+ struct in_addr ip, nmask;
+ char *p;
+ int i, added=0;
+
+ ip.s_addr = 0;
+ nmask.s_addr = 0;
+
+ /* 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].ip,
+ probed_ifaces[i].netmask);
+ added = 1;
+ }
+ }
+ if (added) return;
+
+ /* maybe it is a DNS name */
+ p = strchr_m(token,'/');
+ if (!p) {
+ /* don't try to do dns lookups on wildcard names */
+ if (strpbrk(token, "*?") != NULL) {
+ return;
+ }
+ ip.s_addr = interpret_addr2(token).addr;
+ for (i=0;i<total_probed;i++) {
+ if (ip.s_addr == probed_ifaces[i].ip.s_addr) {
+ add_interface(probed_ifaces[i].ip,
+ probed_ifaces[i].netmask);
+ return;
+ }
+ }
+ DEBUG(2,("can't determine netmask for %s\n", token));
+ return;
+ }
+
+ /* parse it into an IP address/netmasklength pair */
+ *p++ = 0;
+
+ ip.s_addr = interpret_addr2(token).addr;
+
+ if (strlen(p) > 2) {
+ nmask.s_addr = interpret_addr2(p).addr;
+ } else {
+ nmask.s_addr = htonl(((ALLONES >> atoi(p)) ^ ALLONES));
+ }
+
+ /* maybe the first component was a broadcast address */
+ if (ip.s_addr == MKBCADDR(ip.s_addr, nmask.s_addr) ||
+ ip.s_addr == MKNETADDR(ip.s_addr, nmask.s_addr)) {
+ for (i=0;i<total_probed;i++) {
+ if (same_net(tov4(ip), tov4(probed_ifaces[i].ip), tov4(nmask))) {
+ add_interface(probed_ifaces[i].ip, nmask);
+ return;
+ }
+ }
+ DEBUG(2,("Can't determine ip for broadcast address %s\n", token));
+ return;
+ }
+
+ add_interface(ip, nmask);
+}
+
+
+/**
+load the list of network interfaces
+**/
+static void load_interfaces(void)
+{
+ const char **ptr;
+ int i;
+ struct iface_struct ifaces[MAX_INTERFACES];
+ struct ipv4_addr loopback_ip;
+ int total_probed;
+
+ if (local_interfaces != NULL) {
+ return;
+ }
+
+ ptr = lp_interfaces();
+ loopback_ip = interpret_addr2("127.0.0.1");
+
+ /* probe the kernel for interfaces */
+ total_probed = get_interfaces(ifaces, MAX_INTERFACES);
+
+ /* if we don't have a interfaces line then use all 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"));
+ }
+ for (i=0;i<total_probed;i++) {
+ if (ifaces[i].ip.s_addr != loopback_ip.addr) {
+ add_interface(ifaces[i].ip,
+ ifaces[i].netmask);
+ }
+ }
+ }
+
+ while (ptr && *ptr) {
+ interpret_interface(*ptr, ifaces, total_probed);
+ ptr++;
+ }
+
+ if (!local_interfaces) {
+ DEBUG(0,("WARNING: no network interfaces found\n"));
+ }
+}
+
+
+/**
+ unload the interfaces list, so it can be reloaded when needed
+*/
+void unload_interfaces(void)
+{
+ talloc_free(local_interfaces);
+ local_interfaces = NULL;
+}
+
+/**
+ how many interfaces do we have
+ **/
+int iface_count(void)
+{
+ int ret = 0;
+ struct interface *i;
+
+ load_interfaces();
+
+ for (i=local_interfaces;i;i=i->next)
+ ret++;
+ return ret;
+}
+
+/**
+ return IP of the Nth interface
+ **/
+const char *iface_n_ip(int n)
+{
+ struct interface *i;
+
+ load_interfaces();
+
+ for (i=local_interfaces;i && n;i=i->next)
+ n--;
+
+ if (i) {
+ return i->ip_s;
+ }
+ return NULL;
+}
+
+/**
+ return bcast of the Nth interface
+ **/
+const char *iface_n_bcast(int n)
+{
+ struct interface *i;
+
+ load_interfaces();
+
+ for (i=local_interfaces;i && n;i=i->next)
+ n--;
+
+ if (i) {
+ return i->bcast_s;
+ }
+ return NULL;
+}
+
+/**
+ return netmask of the Nth interface
+ **/
+const char *iface_n_netmask(int n)
+{
+ struct interface *i;
+
+ load_interfaces();
+
+ for (i=local_interfaces;i && n;i=i->next)
+ n--;
+
+ if (i) {
+ return i->nmask_s;
+ }
+ return NULL;
+}
+
+/**
+ return the local IP address that best matches a destination IP, or
+ our first interface if none match
+*/
+const char *iface_best_ip(const char *dest)
+{
+ struct interface *iface;
+ struct in_addr ip;
+
+ load_interfaces();
+
+ ip.s_addr = interpret_addr(dest);
+ iface = iface_find(ip, True);
+ if (iface) {
+ return iface->ip_s;
+ }
+ return iface_n_ip(0);
+}
+
+/**
+ return True if an IP is one one of our local networks
+*/
+BOOL iface_is_local(const char *dest)
+{
+ struct in_addr ip;
+
+ load_interfaces();
+
+ ip.s_addr = interpret_addr(dest);
+ if (iface_find(ip, True)) {
+ return True;
+ }
+ return False;
+}
+
+/**
+ return True if a IP matches a IP/netmask pair
+*/
+BOOL iface_same_net(const char *ip1, const char *ip2, const char *netmask)
+{
+ return same_net(interpret_addr2(ip1),
+ interpret_addr2(ip2),
+ interpret_addr2(netmask));
+}