s3: in sys_popen(), fix a debug message

[Samba/gebeck_regimport.git] / source4 / lib / socket / interface.c

/* 
   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 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"
#include "system/network.h"
#include "param/param.h"
#include "lib/socket/netif.h"
#include "../lib/util/util_net.h"
#include "../lib/util/dlinklist.h"

/* used for network interfaces */
struct interface {
        struct interface *next, *prev;
        char *name;
        int flags;
        struct sockaddr_storage ip;
        struct sockaddr_storage netmask;
        struct sockaddr_storage bcast;
        const char *ip_s;
        const char *bcast_s;
        const char *nmask_s;
};

#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)

/****************************************************************************
Try and find an interface that matches an ip. If we cannot, return NULL
  **************************************************************************/
static struct interface *iface_list_find(struct interface *interfaces,
                                         const struct sockaddr *ip,
                                         bool check_mask)
{
        struct interface *i;

        if (is_address_any(ip)) {
                return interfaces;
        }

        for (i=interfaces;i;i=i->next) {
                if (check_mask) {
                        if (same_net(ip, (struct sockaddr *)&i->ip, (struct sockaddr *)&i->netmask)) {
                                return i;
                        }
                } else if (sockaddr_equal((struct sockaddr *)&i->ip, ip)) {
                        return i;
                }
        }

        return NULL;
}

/****************************************************************************
add an interface to the linked list of interfaces
****************************************************************************/
static void add_interface(TALLOC_CTX *mem_ctx, const struct iface_struct *ifs, struct interface **interfaces,
                          bool enable_ipv6)
{
        char addr[INET6_ADDRSTRLEN];
        struct interface *iface;

        if (iface_list_find(*interfaces, (const struct sockaddr *)&ifs->ip, false)) {
                DEBUG(3,("add_interface: not adding duplicate interface %s\n",
                        print_sockaddr(addr, sizeof(addr), &ifs->ip) ));
                return;
        }

        if (ifs->ip.ss_family == AF_INET &&
                !(ifs->flags & (IFF_BROADCAST|IFF_LOOPBACK))) {
                DEBUG(3,("not adding non-broadcast interface %s\n",
                                        ifs->name ));
                return;
        }

        if (!enable_ipv6 && ifs->ip.ss_family != AF_INET) {
                return;
        }

        iface = talloc(*interfaces == NULL ? mem_ctx : *interfaces, struct interface);
        if (iface == NULL) 
                return;
        
        ZERO_STRUCTPN(iface);

        iface->name = talloc_strdup(iface, 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;

        /* keep string versions too, to avoid people tripping over the implied
           static in inet_ntoa() */
        print_sockaddr(addr, sizeof(addr), &iface->ip);
        DEBUG(4,("added interface %s ip=%s ",
                 iface->name, addr));
        iface->ip_s = talloc_strdup(iface, addr);

        print_sockaddr(addr, sizeof(addr),
                       &iface->bcast);
        DEBUG(4,("bcast=%s ", addr));
        iface->bcast_s = talloc_strdup(iface, addr);

        print_sockaddr(addr, sizeof(addr),
                       &iface->netmask);
        DEBUG(4,("netmask=%s\n", addr));
        iface->nmask_s = talloc_strdup(iface, addr);

        /*
           this needs to be a ADD_END, as some tests (such as the
           spoolss notify test) depend on the interfaces ordering
        */
        DLIST_ADD_END(*interfaces, iface, NULL);
}

/**
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(TALLOC_CTX *mem_ctx, 
                                const char *token, 
                                struct iface_struct *probed_ifaces, 
                                int total_probed,
                                struct interface **local_interfaces,
                                bool enable_ipv6)
{
        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(mem_ctx, &probed_ifaces[i],
                                      local_interfaces, enable_ipv6);
                        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 (sockaddr_equal((struct sockaddr *)&ss, (struct sockaddr *)&probed_ifaces[i].ip)) {
                                add_interface(mem_ctx, &probed_ifaces[i],
                                              local_interfaces, enable_ipv6);
                                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 (sockaddr_equal((struct sockaddr *)&ss_bcast, (struct sockaddr *)&ss) ||
                sockaddr_equal((struct sockaddr *)&ss_net, (struct sockaddr *)&ss)) {
                for (i=0;i<total_probed;i++) {
                        if (same_net((struct sockaddr *)&ss,
                                                 (struct sockaddr *)&probed_ifaces[i].ip,
                                                 (struct sockaddr *)&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(mem_ctx, &probed_ifaces[i],
                                              local_interfaces, enable_ipv6);
                                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(mem_ctx, &ifs,
                      local_interfaces, enable_ipv6);
}


/**
load the list of network interfaces
**/
void load_interface_list(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx, struct interface **local_interfaces)
{
        const char **ptr = lpcfg_interfaces(lp_ctx);
        int i;
        struct iface_struct *ifaces = NULL;
        int total_probed;
        bool enable_ipv6 = lpcfg_parm_bool(lp_ctx, NULL, "ipv6", "enable", true);

        *local_interfaces = NULL;

        /* probe the kernel for interfaces */
        total_probed = get_interfaces(mem_ctx, &ifaces);

        /* 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 (!is_loopback_addr((struct sockaddr *)&ifaces[i].ip)) {
                                add_interface(mem_ctx, &ifaces[i], local_interfaces, enable_ipv6);
                        }
                }
        }

        while (ptr && *ptr) {
                interpret_interface(mem_ctx, *ptr, ifaces, total_probed, local_interfaces, enable_ipv6);
                ptr++;
        }

        if (!*local_interfaces) {
                DEBUG(0,("WARNING: no network interfaces found\n"));
        }
        talloc_free(ifaces);
}

/**
  how many interfaces do we have
  **/
int iface_list_count(struct interface *ifaces)
{
        int ret = 0;
        struct interface *i;

        for (i=ifaces;i;i=i->next)
                ret++;
        return ret;
}

/**
  return IP of the Nth interface
  **/
const char *iface_list_n_ip(struct interface *ifaces, int n)
{
        struct interface *i;
  
        for (i=ifaces;i && n;i=i->next)
                n--;

        if (i) {
                return i->ip_s;
        }
        return NULL;
}


/**
  return the first IPv4 interface address we have registered
  **/
const char *iface_list_first_v4(struct interface *ifaces)
{
        struct interface *i;

        for (i=ifaces; i; i=i->next) {
                if (i->ip.ss_family == AF_INET) {
                        return i->ip_s;
                }
        }
        return NULL;
}

/**
  return the first IPv6 interface address we have registered
  **/
static const char *iface_list_first_v6(struct interface *ifaces)
{
        struct interface *i;

#ifdef HAVE_IPV6
        for (i=ifaces; i; i=i->next) {
                if (i->ip.ss_family == AF_INET6) {
                        return i->ip_s;
                }
        }
#endif
        return NULL;
}

/**
   check if an interface is IPv4
  **/
bool iface_list_n_is_v4(struct interface *ifaces, int n)
{
        struct interface *i;

        for (i=ifaces;i && n;i=i->next)
                n--;

        if (i) {
                return i->ip.ss_family == AF_INET;
        }
        return false;
}

/**
  return bcast of the Nth interface
  **/
const char *iface_list_n_bcast(struct interface *ifaces, int n)
{
        struct interface *i;
  
        for (i=ifaces;i && n;i=i->next)
                n--;

        if (i) {
                return i->bcast_s;
        }
        return NULL;
}

/**
  return netmask of the Nth interface
  **/
const char *iface_list_n_netmask(struct interface *ifaces, int n)
{
        struct interface *i;
  
        for (i=ifaces;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_list_best_ip(struct interface *ifaces, const char *dest)
{
        struct interface *iface;
        struct sockaddr_storage ss;

        if (!interpret_string_addr(&ss, dest, AI_NUMERICHOST)) {
                return iface_list_n_ip(ifaces, 0);
        }
        iface = iface_list_find(ifaces, (const struct sockaddr *)&ss, true);
        if (iface) {
                return iface->ip_s;
        }
#ifdef HAVE_IPV6
        if (ss.ss_family == AF_INET6) {
                return iface_list_first_v6(ifaces);
        }
#endif
        return iface_list_first_v4(ifaces);
}

/**
  return true if an IP is one one of our local networks
*/
bool iface_list_is_local(struct interface *ifaces, const char *dest)
{
        struct sockaddr_storage ss;

        if (!interpret_string_addr(&ss, dest, AI_NUMERICHOST)) {
                return false;
        }
        if (iface_list_find(ifaces, (const struct sockaddr *)&ss, true)) {
                return true;
        }
        return false;
}

/**
  return true if a IP matches a IP/netmask pair
*/
bool iface_list_same_net(const char *ip1, const char *ip2, const char *netmask)
{
        struct sockaddr_storage ip1_ss, ip2_ss, nm_ss;

        if (!interpret_string_addr(&ip1_ss, ip1, AI_NUMERICHOST)) {
                return false;
        }
        if (!interpret_string_addr(&ip2_ss, ip2, AI_NUMERICHOST)) {
                return false;
        }
        if (!interpret_string_addr(&nm_ss, netmask, AI_NUMERICHOST)) {
                return false;
        }

        return same_net((struct sockaddr *)&ip1_ss,
                        (struct sockaddr *)&ip2_ss,
                        (struct sockaddr *)&nm_ss);
}

/**
   return the list of wildcard interfaces
   this will include the IPv4 0.0.0.0, and may include IPv6 ::
*/
const char **iface_list_wildcard(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx)
{
        const char **ret;
        ret = (const char **)str_list_make(mem_ctx, "0.0.0.0", NULL);
        if (ret == NULL) return NULL;

#ifdef HAVE_IPV6
        if (lpcfg_parm_bool(lp_ctx, NULL, "ipv6", "enable", true)) {
                struct interface *local_interfaces = NULL;

                load_interface_list(ret, lp_ctx, &local_interfaces);

                if (iface_list_first_v6(local_interfaces)) {
                        TALLOC_FREE(local_interfaces);
                        /*
                         * only add "::" if we have at least
                         * one ipv6 interface
                         */
                        return str_list_add(ret, "::");
                }
                TALLOC_FREE(local_interfaces);
        }
#endif

        return ret;
}