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Diffstat (limited to 'lib/libc/net/if_nameindex.c')
-rw-r--r--lib/libc/net/if_nameindex.c233
1 files changed, 103 insertions, 130 deletions
diff --git a/lib/libc/net/if_nameindex.c b/lib/libc/net/if_nameindex.c
index 2b85fbae959..3675a2a4507 100644
--- a/lib/libc/net/if_nameindex.c
+++ b/lib/libc/net/if_nameindex.c
@@ -1,26 +1,20 @@
-/*
- * Copyright (c) 1998-1999, Craig Metz, All rights reserved.
+/* $OpenBSD: if_nameindex.c,v 1.9 2002/03/07 22:40:23 millert Exp $ */
+/* $KAME: if_nameindex.c,v 1.7 2000/11/24 08:17:20 itojun Exp $ */
+
+/*-
+ * Copyright (c) 1997, 2000
+ * Berkeley Software Design, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by Craig Metz and
- * by other contributors.
- * 4. Neither the name of the author nor the names of contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
*
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
@@ -28,140 +22,119 @@
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
+ *
+ * BSDI Id: if_nameindex.c,v 2.3 2000/04/17 22:38:05 dab Exp
*/
-#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
-#include <sys/ioctl.h>
-#include <net/if.h>
#include <net/if_dl.h>
-#include <errno.h>
-#include <unistd.h>
+#include <net/if.h>
+#include <ifaddrs.h>
+#include <stdlib.h>
#include <string.h>
+/*
+ * From RFC 2553:
+ *
+ * 4.3 Return All Interface Names and Indexes
+ *
+ * The if_nameindex structure holds the information about a single
+ * interface and is defined as a result of including the <net/if.h>
+ * header.
+ *
+ * struct if_nameindex {
+ * unsigned int if_index;
+ * char *if_name;
+ * };
+ *
+ * The final function returns an array of if_nameindex structures, one
+ * structure per interface.
+ *
+ * struct if_nameindex *if_nameindex(void);
+ *
+ * The end of the array of structures is indicated by a structure with
+ * an if_index of 0 and an if_name of NULL. The function returns a NULL
+ * pointer upon an error, and would set errno to the appropriate value.
+ *
+ * The memory used for this array of structures along with the interface
+ * names pointed to by the if_name members is obtained dynamically.
+ * This memory is freed by the next function.
+ *
+ * 4.4. Free Memory
+ *
+ * The following function frees the dynamic memory that was allocated by
+ * if_nameindex().
+ *
+ * #include <net/if.h>
+ *
+ * void if_freenameindex(struct if_nameindex *ptr);
+ *
+ * The argument to this function must be a pointer that was returned by
+ * if_nameindex().
+ */
+
struct if_nameindex *
if_nameindex(void)
{
- int i, j, fd = -1, extra, len = 0;
- struct if_nameindex *nameindex = NULL;
- struct ifconf ifconf;
- char lastname[IFNAMSIZ], *c, *inbuf;
- struct if_nameindex *n;
- struct sockaddr *sa;
- void *p;
-
- ifconf.ifc_buf = NULL;
+ struct ifaddrs *ifaddrs, *ifa;
+ unsigned int ni;
+ size_t nbytes;
+ struct if_nameindex *ifni, *ifni2;
+ char *cp;
- if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0)
- goto ret;
+ if (getifaddrs(&ifaddrs) < 0)
+ return(NULL);
/*
- * Try ifc_len == 0 hack first, to get the actual length.
- * If that fails, revert to a loop which grows the ifc_buf
- * until it is sufficiently large.
+ * First, find out how many interfaces there are, and how
+ * much space we need for the string names.
*/
- extra = sizeof(struct ifreq);
- while (1) {
- ifconf.ifc_len = len;
- if (ioctl(fd, SIOCGIFCONF, (void *) &ifconf) == -1 &&
- ifconf.ifc_buf)
- goto ret;
- if (ifconf.ifc_buf &&
- ifconf.ifc_len + extra < len)
- break;
- if (ifconf.ifc_buf) {
- if (len == 0)
- len = 4096;
- ifconf.ifc_len = len *= 2;
- } else {
- len = ifconf.ifc_len;
- extra = 0;
- }
- inbuf = realloc(ifconf.ifc_buf, ifconf.ifc_len);
- if (inbuf == NULL)
- goto ret;
- ifconf.ifc_buf = inbuf;
- }
-
- i = sizeof(struct if_nameindex);
- j = 0;
- p = ifconf.ifc_buf;
- len = ifconf.ifc_len;
- lastname[0] = 0;
- lastname[sizeof(lastname)-1] = 0;
-
- while (len > 0) {
- if (len < (IFNAMSIZ + sizeof(struct sockaddr)))
- goto ret;
- if (strncmp(lastname, p, IFNAMSIZ)) {
- strlcpy(lastname, p, sizeof(lastname));
- i += sizeof(struct if_nameindex);
- j += strlen(lastname) + 1;
+ ni = 0;
+ nbytes = 0;
+ for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
+ if (ifa->ifa_addr &&
+ ifa->ifa_addr->sa_family == AF_LINK) {
+ nbytes += strlen(ifa->ifa_name) + 1;
+ ni++;
}
- len -= IFNAMSIZ;
- p += IFNAMSIZ;
- sa = p;
-
- if (sa->sa_len < sizeof(struct sockaddr))
- sa->sa_len = sizeof(struct sockaddr);
-
- if (len < sa->sa_len)
- goto ret;
- len -= sa->sa_len;
- p += sa->sa_len;
- }
-
- nameindex = malloc(i + j);
- if (nameindex == NULL) {
- errno = ENOMEM;
- goto ret;
}
- memset(nameindex, 0, i + j);
- n = nameindex;
- p = ifconf.ifc_buf;
- c = (void *) nameindex + i;
- i = 0;
- len = ifconf.ifc_len;
- lastname[0] = 0;
-
- while (len > 0) {
- if (len < IFNAMSIZ + sizeof(struct sockaddr))
- goto ret;
- if (strncmp(lastname, p, IFNAMSIZ)) {
- if (i) {
- if (!n->if_index)
- n->if_index = i;
- n++;
- }
- i++;
- memcpy(lastname, p, sizeof(lastname));
- strlcpy(c, lastname, sizeof(lastname));
- n->if_name = c;
- c += strlen(c) + 1;
- }
- len -= IFNAMSIZ;
- p += IFNAMSIZ;
- sa = p;
+ /*
+ * Next, allocate a chunk of memory, use the first part
+ * for the array of structures, and the last part for
+ * the strings.
+ */
+ cp = malloc((ni + 1) * sizeof(struct if_nameindex) + nbytes);
+ ifni = (struct if_nameindex *)cp;
+ if (ifni == NULL)
+ goto out;
+ cp += (ni + 1) * sizeof(struct if_nameindex);
- if (len < sa->sa_len)
- goto ret;
- if (sa->sa_family == AF_LINK) {
- struct sockaddr_dl *sd = (struct sockaddr_dl *)sa;
- n->if_index = sd->sdl_index;
+ /*
+ * Now just loop through the list of interfaces again,
+ * filling in the if_nameindex array and making copies
+ * of all the strings.
+ */
+ ifni2 = ifni;
+ for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
+ if (ifa->ifa_addr &&
+ ifa->ifa_addr->sa_family == AF_LINK) {
+ ifni2->if_index =
+ ((struct sockaddr_dl*)ifa->ifa_addr)->sdl_index;
+ ifni2->if_name = cp;
+ nbytes = strlen(ifa->ifa_name) + 1;
+ memcpy(cp, ifa->ifa_name, nbytes);
+ ifni2++;
+ cp += nbytes;
}
- len -= sa->sa_len;
- p += sa->sa_len;
}
-
- if (n->if_index == 0)
- n->if_index = i;
-
-ret:
- if (fd != -1)
- close(fd);
- if (ifconf.ifc_buf)
- free(ifconf.ifc_buf);
- return (nameindex);
+ /*
+ * Finally, don't forget to terminate the array.
+ */
+ ifni2->if_index = 0;
+ ifni2->if_name = NULL;
+out:
+ freeifaddrs(ifaddrs);
+ return(ifni);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-24 01:06:23 +0000