[PATCH] New getifaddrs implementation
Thorsten Kukuk
kukuk@suse.de
Fri Mar 28 18:16:00 GMT 2003
Hi,
here is the next try of a IPv6 ready getifaddrs() implementation.
I make only one calloc for the whole struct given back to the caller,
but it is impossible to replace the internal used mallocs with alloca.
I have a version using alloca, but on most of my machines it will
overwrite the stack because I get too much data from the kernel.
And I will fallback to Rolands implementation, if netlink support
is missing from running kernel.
Thorsten
--
Thorsten Kukuk http://www.suse.de/~kukuk/ kukuk@suse.de
SuSE Linux AG Deutschherrnstr. 15-19 D-90429 Nuernberg
--------------------------------------------------------------------
Key fingerprint = A368 676B 5E1B 3E46 CFCE 2D97 F8FD 4E23 56C6 FB4B
-------------- next part --------------
2003-03-28 Thorsten Kukuk <kukuk@suse.de>
* sysdeps/unix/sysv/linux/Dist: add ifaddrs.c
* sysdeps/unix/sysv/linux/ifaddrs.c: New implementation for Linux
* inet/test-ifaddrs.c: Allow AF_PACKET.
* sysdeps/unix/sysv/linux/kernel-features.h: Add __ASSUME_NETLINK_SUPPORT
--- inet/test-ifaddrs.c 2002-12-21 14:38:27.000000000 +0100
+++ inet/test-ifaddrs.c 2003-03-27 21:20:34.000000000 +0100
@@ -69,6 +69,10 @@
#endif
case AF_UNSPEC:
return "---";
+
+ case AF_PACKET:
+ return "<packet>";
+
default:
++failures;
printf ("sa_family=%d %08x\n", sa->sa_family,
--- sysdeps/unix/sysv/linux/Dist 2003-02-26 20:34:23.000000000 +0100
+++ sysdeps/unix/sysv/linux/Dist 2003-03-27 21:20:34.000000000 +0100
@@ -5,6 +5,7 @@
exit-thread.S
getdirentries.c
getdirentries64.c
+ifaddrs.c
ipc_priv.h
kernel-features.h
kernel_sigaction.h
--- sysdeps/unix/sysv/linux/ifaddrs.c 1970-01-01 01:00:00.000000000 +0100
+++ sysdeps/unix/sysv/linux/ifaddrs.c 2003-03-28 19:03:40.000000000 +0100
@@ -0,0 +1,731 @@
+/* getifaddrs -- get names and addresses of all network interfaces
+ Copyright (C) 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <time.h>
+#include <errno.h>
+#include <assert.h>
+#include <net/if.h>
+#include <ifaddrs.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <netpacket/packet.h>
+
+#include <asm/types.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include <stdio.h>
+
+#include "kernel-features.h"
+
+/* We don't know if we have NETLINK support compiled in in our
+ Kernel, so include the old implementation as fallback. */
+#if __ASSUME_NETLINK_SUPPORT == 0
+static int no_netlink_support;
+
+#define getifaddrs fallback_getifaddrs
+#include "sysdeps/gnu/ifaddrs.c"
+#undef getifaddrs
+
+#endif
+
+struct netlink_res
+{
+ struct netlink_res *next;
+ struct nlmsghdr *nlh;
+ size_t size; /* size of response. */
+ uint32_t seq; /* sequentiel number we used. */
+};
+
+struct netlink_handle
+{
+ int fd; /* netlink file descriptor. */
+ pid_t pid; /* Process ID. */
+ uint32_t seq; /* the sequentiell number we use currently. */
+ struct netlink_res *nlm_list; /* pointer to list of responses. */
+ struct netlink_res *end_ptr; /* for faster append of new entries. */
+};
+
+/* struct to hold the data for one ifaddrs entry, so we can allocate
+ everything at once. */
+struct ifaddrs_storage
+{
+ struct ifaddrs ifa;
+ union
+ {
+ /* save space for the biggest of the four used sockaddr types and
+ avoid a lot of casts. */
+ struct sockaddr sa;
+ struct sockaddr_ll sl;
+ struct sockaddr_in s4;
+ struct sockaddr_in6 s6;
+ } addr, netmask, broadaddr;
+ char name[IF_NAMESIZE + 1];
+};
+
+static void
+free_netlink_handle (struct netlink_handle *h)
+{
+ struct netlink_res *ptr;
+ int saved_errno = errno;
+
+ if (h->nlm_list == NULL)
+ return;
+
+ ptr = h->nlm_list;
+ while (ptr)
+ {
+ struct netlink_res *tmpptr;
+
+ if (ptr->nlh)
+ free (ptr->nlh);
+ tmpptr = ptr->next;
+ free (ptr);
+ ptr = tmpptr;
+ }
+
+ errno = saved_errno;
+}
+
+static int
+netlink_sendreq (struct netlink_handle *h, int type)
+{
+ struct
+ {
+ struct nlmsghdr nlh;
+ struct rtgenmsg g;
+ } req;
+ struct sockaddr_nl nladdr;
+
+ if (h->seq == 0)
+ h->seq = time (NULL);
+
+ req.nlh.nlmsg_len = sizeof (req);
+ req.nlh.nlmsg_type = type;
+ req.nlh.nlmsg_flags = NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST;
+ req.nlh.nlmsg_pid = 0;
+ req.nlh.nlmsg_seq = h->seq;
+ req.g.rtgen_family = AF_UNSPEC;
+
+ memset (&nladdr, 0, sizeof (nladdr));
+ nladdr.nl_family = AF_NETLINK;
+
+ return sendto (h->fd, (void *) &req, sizeof (req), 0,
+ (struct sockaddr *) &nladdr, sizeof (nladdr));
+}
+
+static int
+netlink_receive(struct netlink_handle *h)
+{
+ struct netlink_res *nlm_next;
+ char buf[4096];
+ struct iovec iov = { buf, sizeof (buf) };
+ struct sockaddr_nl nladdr;
+ struct nlmsghdr *nlmh;
+ int read_len, done = 0;
+
+ while (!done)
+ {
+ struct msghdr msg = {
+ (void *) &nladdr, sizeof (nladdr),
+ &iov, 1,
+ NULL, 0,
+ 0
+ };
+
+ do
+ {
+ read_len = recvmsg (h->fd, &msg, 0);
+ }
+ while ((read_len < 0) && (errno == EINTR));
+
+ if (read_len < 0)
+ return -1;
+
+ if (msg.msg_flags & MSG_TRUNC)
+ return -1;
+
+ nlm_next = malloc (sizeof (struct netlink_res));
+ nlm_next->next = NULL;
+ nlm_next->nlh = malloc (read_len);
+ memcpy (nlm_next->nlh, buf, read_len);
+ nlm_next->size = read_len;
+ nlm_next->seq = h->seq;
+ if (h->nlm_list == NULL)
+ {
+ h->nlm_list = nlm_next;
+ h->end_ptr = nlm_next;
+ }
+ else
+ {
+ h->end_ptr->next = nlm_next;
+ h->end_ptr = nlm_next;
+ }
+
+ for (nlmh = (struct nlmsghdr *) buf;
+ NLMSG_OK (nlmh, (size_t) read_len);
+ nlmh = (struct nlmsghdr *) NLMSG_NEXT (nlmh, read_len))
+ {
+ if ((pid_t) nlmh->nlmsg_pid != h->pid || nlmh->nlmsg_seq != h->seq)
+ continue;
+
+ if (nlmh->nlmsg_type == NLMSG_DONE)
+ {
+ /* we found the end, leave the loop. */
+ ++done;
+ break;
+ }
+ if (nlmh->nlmsg_type == NLMSG_ERROR)
+ {
+ struct nlmsgerr *nlerr = (struct nlmsgerr *) NLMSG_DATA (nlmh);
+ if (nlmh->nlmsg_len < NLMSG_LENGTH (sizeof (struct nlmsgerr)))
+ errno = EIO;
+ else
+ errno = -nlerr->error;
+ return -1;
+ }
+ }
+ }
+ return 0;
+}
+
+static void
+netlink_close (struct netlink_handle *h)
+{
+ /* save errno, so that netlink_close will not overwrite previous
+ error code. */
+ int saved_errno = errno;
+
+ close (h->fd);
+ errno = saved_errno;
+}
+
+/* Open a NETLINK socket. */
+static int
+netlink_open (struct netlink_handle *h)
+{
+ struct sockaddr_nl nladdr;
+
+ h->fd = socket (PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (h->fd < 0)
+ return -1;
+
+ memset (&nladdr, 0, sizeof (nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ if (bind (h->fd, (struct sockaddr *) &nladdr, sizeof (nladdr)) < 0)
+ {
+ netlink_close (h);
+ return -1;
+ }
+ return 0;
+}
+
+/* We know the number of RTM_NEWLINK entries, so we reserve the first
+ # of entries for this type. All RTM_NEWADDR entries have a index
+ pointer to the RTM_NEWLINK entry. To find the entry, create
+ a table to map kernel index entries to our index numbers.
+ Since we get at first all RTM_NEWLINK entries, it can never happen
+ that a RTM_NEWADDR index is not known to this map. */
+static int
+map_newlink (int index, int *map, int max)
+{
+ int i;
+
+ for (i = 0; i < max; i++)
+ {
+ if (map[i] == -1)
+ {
+ map[i] = index;
+ return i;
+ }
+ else if (map[i] == index)
+ return i;
+ }
+ /* this should never be reached. If this will be reached, we have
+ very big problem. */
+ abort ();
+}
+
+/* Create a linked list of `struct ifaddrs' structures, one for each
+ network interface on the host machine. If successful, store the
+ list in *IFAP and return 0. On errors, return -1 and set `errno'. */
+int
+getifaddrs (struct ifaddrs **ifap)
+{
+ struct netlink_handle nh = { 0, 0, 0, NULL, NULL };
+ struct netlink_res *nlp;
+ struct ifaddrs_storage *ifas;
+ unsigned int i, newlink, newaddr, newaddr_idx;
+ int *map_newlink_data;
+ size_t ifa_data_size = 0; /* size to allocate for all ifa_data. */
+ char *ifa_data_ptr; /* pointer to the unused part of memory for ifa_data. */
+
+#if __ASSUME_NETLINK_SUPPORT == 0
+ if (no_netlink_support)
+ return fallback_getifaddrs (ifap);
+#endif
+
+ if (ifap)
+ *ifap = NULL;
+
+ if (netlink_open (&nh) < 0)
+#if __ASSUME_NETLINK_SUPPORT == 0
+ {
+ no_netlink_support = 1;
+ return fallback_getifaddrs (ifap);
+ }
+#else
+ return -1;
+#endif
+
+ nh.pid = getpid ();
+
+ /* Tell the kernel that we wish to get a list of all
+ active interfaces. */
+ if (netlink_sendreq (&nh, RTM_GETLINK) < 0)
+ {
+ netlink_close (&nh);
+ return -1;
+ }
+ /* Collect all data for every interface. */
+ if (netlink_receive (&nh) < 0)
+ {
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ return -1;
+ }
+
+
+ /* Now ask the kernel for all addresses which are assigned
+ to an interface. Since we store the addresses after the
+ interfaces in the list, we will later always find the
+ interface before the corresponding addresses. */
+ ++nh.seq;
+ if (netlink_sendreq (&nh, RTM_GETADDR) < 0)
+ {
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ return -1;
+ }
+ /* Collect all data for every inerface. */
+ if (netlink_receive (&nh) < 0)
+ {
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ return -1;
+ }
+
+ /* Count all RTM_NEWLINK and RTM_NEWADDR entries to allocate
+ enough memory. */
+ newlink = newaddr = 0;
+ for (nlp = nh.nlm_list; nlp; nlp = nlp->next)
+ {
+ struct nlmsghdr *nlh;
+ size_t size = nlp->size;
+
+ if (nlp->nlh == NULL)
+ continue;
+
+ /* Walk through all entries we got from the kernel and look, which
+ message type they contain. */
+ for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size))
+ {
+ /* check if the message is what we want */
+ if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq)
+ continue;
+
+ if (nlh->nlmsg_type == NLMSG_DONE)
+ break; /* ok */
+
+ if (nlh->nlmsg_type == RTM_NEWLINK)
+ {
+ /* A RTM_NEWLINK message can have IFLA_STATS data. We need to
+ know the size before creating the list to allocate enough
+ memory. */
+ struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh);
+ struct rtattr *rta = IFLA_RTA (ifim);
+ size_t rtasize = IFLA_PAYLOAD (nlh);
+
+ while (RTA_OK (rta, rtasize))
+ {
+ size_t rta_payload = RTA_PAYLOAD (rta);
+
+ if (rta->rta_type == IFLA_STATS)
+ {
+ ifa_data_size += rta_payload;
+ break;
+ }
+ else
+ rta = RTA_NEXT (rta, rtasize);
+ }
+ ++newlink;
+ }
+ else if (nlh->nlmsg_type == RTM_NEWADDR)
+ ++newaddr;
+ }
+ }
+
+ /* return if no interface is up. */
+ if ((newlink + newaddr) == 0)
+ {
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ return 0;
+ }
+
+ /* table for mapping kernel index to entry in our list. */
+ map_newlink_data = alloca (newlink * sizeof (int));
+
+ /* allocate memory for all entries we have and initialize next
+ pointer. */
+ ifas = calloc (1, (newlink + newaddr) * sizeof (struct ifaddrs_storage)
+ + ifa_data_size);
+ if (ifas == NULL)
+ {
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ return -1;
+ }
+
+ for (i = 0; i < newlink + newaddr - 1; i++)
+ {
+ ifas[i].ifa.ifa_next = &ifas[i + 1].ifa;
+ map_newlink_data[i] = -1;
+ }
+ ifa_data_ptr = (char *)&ifas[newlink + newaddr];
+ newaddr_idx = 0; /* counter for newaddr index. */
+
+ /* Walk through the list of data we got from the kernel. */
+ for (nlp = nh.nlm_list; nlp; nlp = nlp->next)
+ {
+ struct nlmsghdr *nlh;
+ size_t size = nlp->size;
+
+ if (nlp->nlh == NULL)
+ continue;
+
+ /* Walk through one message and look at the type: If it is our
+ message, we need RTM_NEWLINK/RTM_NEWADDR and stop if we reach
+ the end or we find the end marker (in this case we ignore the
+ following data. */
+ for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size))
+ {
+ int ifa_index = 0;
+
+ /* check if the message is the one we want */
+ if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq)
+ continue;
+
+ if (nlh->nlmsg_type == NLMSG_DONE)
+ break; /* ok */
+ else if (nlh->nlmsg_type == RTM_NEWLINK)
+ {
+ /* We found a new interface. Now extract everything from the
+ interface data we got and need. */
+ struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh);
+ struct rtattr *rta = IFLA_RTA (ifim);
+ size_t rtasize = IFLA_PAYLOAD (nlh);
+
+ /* interfaces are stored in the first "newlink" entries
+ of our list, starting in the order as we got from the
+ kernel. */
+ ifa_index = map_newlink (ifim->ifi_index - 1,
+ map_newlink_data, newlink);
+ ifas[ifa_index].ifa.ifa_flags = ifim->ifi_flags;
+
+ while (RTA_OK (rta, rtasize))
+ {
+ char *rta_data = RTA_DATA (rta);
+ size_t rta_payload = RTA_PAYLOAD (rta);
+
+ switch (rta->rta_type)
+ {
+ case IFLA_ADDRESS:
+ ifas[ifa_index].addr.sl.sll_family = AF_PACKET;
+ memcpy (ifas[ifa_index].addr.sl.sll_addr, (char *) rta_data,
+ rta_payload);
+ ifas[ifa_index].addr.sl.sll_halen = rta_payload;
+ ifas[ifa_index].addr.sl.sll_ifindex = ifim->ifi_index;
+ ifas[ifa_index].addr.sl.sll_hatype = ifim->ifi_type;
+
+ ifas[ifa_index].ifa.ifa_addr = &ifas[ifa_index].addr.sa;
+ break;
+ case IFLA_BROADCAST:
+ ifas[ifa_index].broadaddr.sl.sll_family = AF_PACKET;
+ memcpy (ifas[ifa_index].broadaddr.sl.sll_addr, (char *) rta_data,
+ rta_payload);
+ ifas[ifa_index].broadaddr.sl.sll_halen = rta_payload;
+ ifas[ifa_index].broadaddr.sl.sll_ifindex = ifim->ifi_index;
+ ifas[ifa_index].broadaddr.sl.sll_hatype = ifim->ifi_type;
+
+ ifas[ifa_index].ifa.ifa_broadaddr = &ifas[ifa_index].broadaddr.sa;
+ break;
+ case IFLA_IFNAME: /* Name of Interface */
+ if ((rta_payload + 1) <= sizeof (ifas[ifa_index].name))
+ {
+ ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name;
+ strncpy (ifas[ifa_index].name, rta_data,
+ rta_payload);
+ ifas[ifa_index].name[rta_payload] = '\0';
+ }
+ break;
+ case IFLA_STATS: /* Statistics of Interface */
+ ifas[ifa_index].ifa.ifa_data = ifa_data_ptr;
+ ifa_data_ptr += rta_payload;
+ memcpy (ifas[ifa_index].ifa.ifa_data, rta_data,
+ rta_payload);
+ break;
+ case IFLA_UNSPEC:
+ break;
+ case IFLA_MTU:
+ break;
+ case IFLA_LINK:
+ break;
+ case IFLA_QDISC:
+ break;
+ default:
+ break;
+ }
+
+ rta = RTA_NEXT (rta, rtasize);
+ }
+ }
+ else if (nlh->nlmsg_type == RTM_NEWADDR)
+ {
+ struct ifaddrmsg *ifam = (struct ifaddrmsg *) NLMSG_DATA (nlh);
+ struct rtattr *rta = IFA_RTA (ifam);
+ size_t rtasize = IFA_PAYLOAD (nlh);
+
+ /* New Addresses are stored in the order we got them from
+ the kernel after interfaces. Theoretical it is possible
+ that we have holes in the interface part of the list,
+ but we always have already the interface for this
+ address. */
+ ifa_index = newlink + newaddr_idx;
+ ifas[ifa_index].ifa.ifa_flags = ifas[map_newlink(ifam->ifa_index - 1, map_newlink_data, newlink)].ifa.ifa_flags;
+ ++newaddr_idx;
+
+ while (RTA_OK (rta, rtasize))
+ {
+ char *rta_data = RTA_DATA (rta);
+ size_t rta_payload = RTA_PAYLOAD (rta);
+
+ switch (rta->rta_type)
+ {
+ case IFA_ADDRESS:
+ {
+ struct sockaddr *sa;
+
+ if (ifas[ifa_index].ifa.ifa_addr != NULL)
+ {
+ /* In a point-to-poing network IFA_ADDRESS
+ contains the destination address, local
+ address is supplied in IFA_LOCAL attribute.
+ destination address and broadcast address
+ are stored in a union, so it doesn't matter
+ which name we use. */
+ ifas[ifa_index].ifa.ifa_broadaddr =
+ &ifas[ifa_index].broadaddr.sa;
+ sa = &ifas[ifa_index].broadaddr.sa;
+ }
+ else
+ {
+ ifas[ifa_index].ifa.ifa_addr =
+ &ifas[ifa_index].addr.sa;
+ sa = &ifas[ifa_index].addr.sa;
+ }
+ sa->sa_family = ifam->ifa_family;
+ switch (ifam->ifa_family)
+ {
+ case AF_INET:
+ memcpy (&((struct sockaddr_in *) sa)->sin_addr,
+ rta_data, rta_payload);
+ break;
+ case AF_INET6:
+ memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr,
+ rta_data, rta_payload);
+ if (IN6_IS_ADDR_LINKLOCAL (rta_data) ||
+ IN6_IS_ADDR_MC_LINKLOCAL (rta_data))
+ ((struct sockaddr_in6 *) sa)->sin6_scope_id =
+ ifam->ifa_scope;
+ break;
+ default:
+ memcpy (sa->sa_data, rta_data, rta_payload);
+ break;
+ }
+ }
+ break;
+ case IFA_LOCAL:
+ if (ifas[ifa_index].ifa.ifa_addr != NULL)
+ {
+ /* If ifa_addr is set and we get IFA_LOCAL,
+ assume we have a point-to-point network.
+ Move address to correct field. */
+ ifas[ifa_index].broadaddr = ifas[ifa_index].addr;
+ ifas[ifa_index].ifa.ifa_broadaddr =
+ &ifas[ifa_index].broadaddr.sa;
+ memset (&ifas[ifa_index].addr, 0,
+ sizeof (ifas[ifa_index].addr));
+ }
+
+ ifas[ifa_index].ifa.ifa_addr = &ifas[ifa_index].addr.sa;
+ ifas[ifa_index].ifa.ifa_addr->sa_family =
+ ifam->ifa_family;
+ switch (ifam->ifa_family)
+ {
+ case AF_INET:
+ memcpy (&ifas[ifa_index].addr.s4.sin_addr,
+ rta_data, rta_payload);
+ break;
+ case AF_INET6:
+ memcpy (&ifas[ifa_index].addr.s6.sin6_addr,
+ rta_data, rta_payload);
+ if (IN6_IS_ADDR_LINKLOCAL (rta_data) ||
+ IN6_IS_ADDR_MC_LINKLOCAL (rta_data))
+ ifas[ifa_index].addr.s6.sin6_scope_id =
+ ifam->ifa_scope;
+ break;
+ default:
+ memcpy (ifas[ifa_index].addr.sa.sa_data,
+ rta_data, rta_payload);
+ break;
+ }
+ break;
+ case IFA_BROADCAST:
+ /* We get IFA_BROADCAST, so IFA_LOCAL was too much. */
+ if (ifas[ifa_index].ifa.ifa_broadaddr != NULL)
+ memset (&ifas[ifa_index].broadaddr, 0,
+ sizeof (ifas[ifa_index].broadaddr));
+
+ ifas[ifa_index].ifa.ifa_broadaddr =
+ &ifas[ifa_index].broadaddr.sa;
+ ifas[ifa_index].ifa.ifa_broadaddr->sa_family =
+ ifam->ifa_family;
+ switch (ifam->ifa_family)
+ {
+ case AF_INET:
+ memcpy (&ifas[ifa_index].broadaddr.s4.sin_addr,
+ rta_data, rta_payload);
+ break;
+ case AF_INET6:
+ memcpy (&ifas[ifa_index].broadaddr.s6.sin6_addr,
+ rta_data, rta_payload);
+ if (IN6_IS_ADDR_LINKLOCAL (rta_data) ||
+ IN6_IS_ADDR_MC_LINKLOCAL (rta_data))
+ ifas[ifa_index].broadaddr.s6.sin6_scope_id =
+ ifam->ifa_scope;
+ break;
+ default:
+ memcpy (&ifas[ifa_index].broadaddr.sa.sa_data,
+ rta_data, rta_payload);
+ break;
+ }
+ break;
+ case IFA_LABEL:
+ if (rta_payload + 1 <= sizeof (ifas[ifa_index].name))
+ {
+ ifas[ifa_index].ifa.ifa_name = ifas[ifa_index].name;
+ strncpy (ifas[ifa_index].name, rta_data,
+ rta_payload);
+ ifas[ifa_index].name[rta_payload] = '\0';
+ }
+ else
+ abort ();
+ break;
+ case IFA_UNSPEC:
+ break;
+ case IFA_CACHEINFO:
+ break;
+ default:
+ break;
+ }
+
+ rta = RTA_NEXT (rta, rtasize);
+ }
+
+ /* If we didn't get the interface name with the
+ address, use the name from the interface entry. */
+ if (ifas[ifa_index].ifa.ifa_name == NULL)
+ ifas[ifa_index].ifa.ifa_name =
+ ifas[map_newlink(ifam->ifa_index - 1,
+ map_newlink_data, newlink)].ifa.ifa_name;
+
+ /* Calculate the netmask. */
+ if (ifas[ifa_index].ifa.ifa_addr &&
+ ifas[ifa_index].ifa.ifa_addr->sa_family != AF_UNSPEC &&
+ ifas[ifa_index].ifa.ifa_addr->sa_family != AF_PACKET)
+ {
+ uint32_t max_prefixlen = 0;
+ char *cp = NULL;
+
+ ifas[ifa_index].ifa.ifa_netmask = &ifas[ifa_index].netmask.sa;
+ switch (ifas[ifa_index].ifa.ifa_addr->sa_family)
+ {
+ case AF_INET:
+ cp = (char *) &ifas[ifa_index].netmask.s4.sin_addr;
+ max_prefixlen = 32;
+ break;
+ case AF_INET6:
+ cp = (char *) &ifas[ifa_index].netmask.s6.sin6_addr;
+ max_prefixlen = 128;
+ break;
+ }
+ ifas[ifa_index].ifa.ifa_netmask->sa_family =
+ ifas[ifa_index].ifa.ifa_addr->sa_family;
+ if (cp)
+ {
+ char c;
+ unsigned int preflen;
+
+ if ((max_prefixlen > 0) &&
+ (ifam->ifa_prefixlen > max_prefixlen))
+ preflen = max_prefixlen;
+ else
+ preflen = ifam->ifa_prefixlen;
+
+ for (i = 0; i < (preflen / 8); i++)
+ *cp++ = 0xff;
+ c = 0xff;
+ c <<= (8 - (preflen % 8));
+ *cp = c;
+ }
+ }
+ }
+ }
+ }
+
+ free_netlink_handle (&nh);
+ netlink_close (&nh);
+ if (ifap != NULL)
+ *ifap = &ifas[0].ifa;
+
+ return 0;
+}
+
+#if __ASSUME_NETLINK_SUPPORT == 1
+void
+freeifaddrs (struct ifaddrs *ifa)
+{
+ free (ifa);
+}
+#endif
--- sysdeps/unix/sysv/linux/kernel-features.h 2003-03-27 20:29:57.000000000 +0100
+++ sysdeps/unix/sysv/linux/kernel-features.h 2003-03-27 21:34:20.000000000 +0100
@@ -279,3 +279,9 @@
&& (defined __ia64__ || defined __s390__ || defined __powerpc__)
# define __ASSUME_CLONE_THREAD_FLAGS 1
#endif
+
+/* With kernel 2.4.17 we always have netlink support. */
+#if __LINUX_KERNEL_VERSION >= (132096+17)
+# define __ASSUME_NETLINK_SUPPORT 1
+#endif
+
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