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-rw-r--r--libc/inet/if_index.c346
1 files changed, 346 insertions, 0 deletions
diff --git a/libc/inet/if_index.c b/libc/inet/if_index.c
new file mode 100644
index 000000000..40e46d538
--- /dev/null
+++ b/libc/inet/if_index.c
@@ -0,0 +1,346 @@
+/* Copyright (C) 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005
+ 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.
+
+ Reworked Dec 2002 by Erik Andersen <andersen@codepoet.org>
+ */
+
+#define strndup __strndup
+
+#define __FORCE_GLIBC
+#include <features.h>
+#define __USE_GNU
+#include <string.h>
+#include <alloca.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <net/if.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <libc-internal.h>
+
+#include "netlinkaccess.h"
+
+extern int __opensock(void) attribute_hidden;
+
+unsigned int
+if_nametoindex(const char* ifname)
+{
+#ifndef SIOCGIFINDEX
+ __set_errno (ENOSYS);
+ return 0;
+#else
+ struct ifreq ifr;
+ int fd = __opensock();
+
+ if (fd < 0)
+ return 0;
+
+ __strncpy (ifr.ifr_name, ifname, sizeof (ifr.ifr_name));
+ if (__ioctl (fd, SIOCGIFINDEX, &ifr) < 0)
+ {
+ int saved_errno = errno;
+ __close(fd);
+ if (saved_errno == EINVAL)
+ __set_errno(ENOSYS);
+ return 0;
+ }
+
+ __close(fd);
+ return ifr.ifr_ifindex;
+#endif
+}
+hidden_strong_alias(if_nametoindex,__if_nametoindex)
+
+void
+if_freenameindex (struct if_nameindex *ifn)
+{
+ struct if_nameindex *ptr = ifn;
+ while (ptr->if_name || ptr->if_index)
+ {
+ free (ptr->if_name);
+ ++ptr;
+ }
+ free (ifn);
+}
+hidden_strong_alias(if_freenameindex,__if_freenameindex)
+
+#if !__ASSUME_NETLINK_SUPPORT
+struct if_nameindex *
+if_nameindex (void)
+{
+#ifndef SIOCGIFINDEX
+ __set_errno (ENOSYS);
+ return NULL;
+#else
+ int fd = __opensock ();
+ struct ifconf ifc;
+ unsigned int nifs, i;
+ int rq_len;
+ struct if_nameindex *idx = NULL;
+# define RQ_IFS 4
+
+ if (fd < 0)
+ return NULL;
+
+ ifc.ifc_buf = NULL;
+
+ /* Guess on the correct buffer size... */
+ rq_len = RQ_IFS * sizeof (struct ifreq);
+
+ /* Read all the interfaces out of the kernel. */
+ /* Note: alloca's in this loop are diff from glibc because it's smaller */
+ do
+ {
+ ifc.ifc_buf = extend_alloca (ifc.ifc_buf, rq_len, 2 * rq_len);
+ ifc.ifc_len = rq_len;
+
+ if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0)
+ {
+ __close (fd);
+ return NULL;
+ }
+ }
+ while (ifc.ifc_len == rq_len);
+
+ nifs = ifc.ifc_len / sizeof(struct ifreq);
+
+ idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
+ if (idx == NULL)
+ {
+ __close(fd);
+ __set_errno(ENOBUFS);
+ return NULL;
+ }
+
+ for (i = 0; i < nifs; ++i)
+ {
+ struct ifreq *ifr = &ifc.ifc_req[i];
+ idx[i].if_name = __strdup (ifr->ifr_name);
+ if (idx[i].if_name == NULL
+ || __ioctl (fd, SIOCGIFINDEX, ifr) < 0)
+ {
+ int saved_errno = errno;
+ unsigned int j;
+
+ for (j = 0; j < i; ++j)
+ free (idx[j].if_name);
+ free(idx);
+ __close(fd);
+ if (saved_errno == EINVAL)
+ saved_errno = ENOSYS;
+ else if (saved_errno == ENOMEM)
+ saved_errno = ENOBUFS;
+ __set_errno (saved_errno);
+ return NULL;
+ }
+ idx[i].if_index = ifr->ifr_ifindex;
+ }
+
+ idx[i].if_index = 0;
+ idx[i].if_name = NULL;
+
+ __close(fd);
+ return idx;
+#endif
+}
+#else
+struct if_nameindex *
+if_nameindex (void)
+{
+ unsigned int nifs = 0;
+ struct netlink_handle nh = { 0, 0, 0, NULL, NULL };
+ struct if_nameindex *idx = NULL;
+ struct netlink_res *nlp;
+
+ if (__netlink_open (&nh) < 0)
+ return NULL;
+
+
+ /* Tell the kernel that we wish to get a list of all
+ active interfaces. Collect all data for every interface. */
+ if (__netlink_request (&nh, RTM_GETLINK) < 0)
+ goto exit_free;
+
+ /* Count the interfaces. */
+ 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)
+ ++nifs;
+ }
+ }
+
+ idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
+ if (idx == NULL)
+ {
+ nomem:
+ __set_errno (ENOBUFS);
+ goto exit_free;
+ }
+
+ /* Add the interfaces. */
+ nifs = 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)
+ {
+ struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh);
+ struct rtattr *rta = IFLA_RTA (ifim);
+ size_t rtasize = IFLA_PAYLOAD (nlh);
+
+ idx[nifs].if_index = ifim->ifi_index;
+
+ while (RTA_OK (rta, rtasize))
+ {
+ char *rta_data = RTA_DATA (rta);
+ size_t rta_payload = RTA_PAYLOAD (rta);
+
+ if (rta->rta_type == IFLA_IFNAME)
+ {
+ idx[nifs].if_name = __strndup (rta_data, rta_payload);
+ if (idx[nifs].if_name == NULL)
+ {
+ idx[nifs].if_index = 0;
+ __if_freenameindex (idx);
+ idx = NULL;
+ goto nomem;
+ }
+ break;
+ }
+
+ rta = RTA_NEXT (rta, rtasize);
+ }
+
+ ++nifs;
+ }
+ }
+ }
+
+ idx[nifs].if_index = 0;
+ idx[nifs].if_name = NULL;
+
+ exit_free:
+ __netlink_free_handle (&nh);
+ __netlink_close (&nh);
+
+ return idx;
+}
+#endif
+hidden_strong_alias(if_nameindex,__if_nameindex)
+
+#if 0
+struct if_nameindex *
+if_nameindex (void)
+{
+ return (if_nameindex_netlink () != NULL ? : if_nameindex_ioctl ());
+}
+#endif
+
+char *
+if_indextoname (unsigned int ifindex, char *ifname)
+{
+#if !defined SIOCGIFINDEX
+ __set_errno (ENOSYS);
+ return NULL;
+#else
+# ifdef SIOCGIFNAME
+ /* Use ioctl to avoid searching the list. */
+ struct ifreq ifr;
+ int fd;
+
+ fd = __opensock ();
+
+ if (fd < 0)
+ return NULL;
+
+ ifr.ifr_ifindex = ifindex;
+ if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
+ {
+ int serrno = errno;
+ __close (fd);
+ if (serrno == ENODEV)
+ /* POSIX requires ENXIO. */
+ serrno = ENXIO;
+ __set_errno (serrno);
+ return NULL;
+ }
+ __close (fd);
+
+ return __strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
+# else
+ struct if_nameindex *idx;
+ struct if_nameindex *p;
+ char *result = NULL;
+
+ idx = __if_nameindex();
+
+ if (idx != NULL)
+ {
+ for (p = idx; p->if_index || p->if_name; ++p)
+ if (p->if_index == ifindex)
+ {
+ result = __strncpy (ifname, p->if_name, IFNAMSIZ);
+ break;
+ }
+
+ __if_freenameindex (idx);
+
+ if (result == NULL)
+ __set_errno (ENXIO);
+ }
+ return result;
+# endif
+#endif
+}
+
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