Implement if_nameindex & if_freenameindex

Author: MedourMehdi

include/net/if.h

@@ -218,9 +218,18 @@ struct sockaddr_hw {
 	unsigned char	shw_addr[8];	/* address */
 };
 
+struct if_nameindex {
+	short	if_index;      /* 1, 2, ... */
+	char*	if_name;       /* null terminated name: "le0", ... */
+};
+
 /* Convert an interface name to an index, and vice versa.  */
 extern unsigned short if_nametoindex (const char *__ifname) __THROW;
 extern char *if_indextoname (unsigned short __ifindex, char __ifname[IF_NAMESIZE]) __THROW;
+/* Return a list of all interfaces and their indices.  */
+extern struct if_nameindex *if_nameindex (void) __THROW;
+/* Free the data returned from if_nameindex.  */
+extern void if_freenameindex (struct if_nameindex *__ptr) __THROW;
 
 __END_DECLS
 

socket/SRCFILES

@@ -38,7 +38,9 @@ SRCFILES = \
 	hstrerror.c \
 	hton.c \
 	ident_sock.c \
+	if_freenameindex.c \
 	if_indextoname.c \
+	if_nameindex.c \
 	if_nametoindex.c \
 	inet_addr.c \
 	inet_lnaof.c \

socket/if_freenameindex.c

@@ -0,0 +1,12 @@
+#include <net/if.h>
+#include <stdlib.h>
+
+__typeof__(if_freenameindex) __if_freenameindex;
+
+void 
+__if_freenameindex(struct if_nameindex *idx)
+{
+	free(idx);
+}
+
+weak_alias (__if_freenameindex, if_freenameindex)

socket/if_indextoname.c

@@ -7,23 +7,24 @@
 
 __typeof__(if_indextoname) __if_indextoname;
 
-char *
+char*
 __if_indextoname(unsigned short index, char name[IF_NAMESIZE])
 {
 	struct ifreq ifr;
 	int fd, r;
 
 	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0){ 
-        __set_errno (ENXIO);
-        return NULL;
-    }
+		__set_errno (ENXIO);
+		return NULL;
+	}
 	ifr.ifr_ifindex = index;
 	r = ioctl(fd, SIOCGIFNAME_ETH, &ifr);
 	close(fd);
-    if(!r){
-        return strncpy(name, ifr.ifr_name, IF_NAMESIZE);
-    }
-    __set_errno (ENXIO);
+	if(!r){
+		return strncpy(name, ifr.ifr_name, IF_NAMESIZE);
+	}
+	__set_errno (ENXIO);
 	return NULL;
 }
+
 weak_alias (__if_indextoname, if_indextoname)

socket/if_nameindex.c

@@ -0,0 +1,149 @@
+/*	$KAME: if_nameindex.c,v 1.8 2000/11/24 08:20:01 itojun Exp $	*/
+
+/*-
+ * SPDX-License-Identifier: BSD-1-Clause
+ *
+ * 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.
+ *
+ * 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 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)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * 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 <sys/types.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <ifaddrs.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.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().
+ */
+
+__typeof__(if_nameindex) __if_nameindex;
+
+struct if_nameindex*
+__if_nameindex (void)
+{
+	struct ifaddrs *ifaddrs, *ifa;
+	unsigned int ni;
+	int nbytes;
+	struct if_nameindex *ifni, *ifni2;
+	char *cp;
+
+	if (getifaddrs(&ifaddrs) < 0){
+		__set_errno (ENOBUFS);
+		return(NULL);
+	}
+	/*
+	 * First, find out how many interfaces there are, and how
+	 * much space we need for the string names.
+	 */
+	ni = 0;
+	nbytes = 0;
+
+	for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
+		if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) {
+			nbytes += strlen(ifa->ifa_name) + 1;
+			ni++;
+		}
+	}
+
+	/*
+	 * 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){
+		__set_errno (ENOBUFS);
+		goto out;
+	}
+	cp += (ni + 1) * sizeof(struct if_nameindex);
+	/*
+	 * 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_INET) {
+
+			ifni2->if_index = if_nametoindex(ifa->ifa_name);
+
+			ifni2->if_name = cp;
+			strcpy(cp, ifa->ifa_name);
+			ifni2++;
+			cp += strlen(cp) + 1;
+		}
+	}
+
+	/*
+	 * Finally, don't forget to terminate the array.
+	 */
+	ifni2->if_index = 0;
+	ifni2->if_name = NULL;
+out:
+	freeifaddrs(ifaddrs);
+	return(ifni);
+}
+
+weak_alias (__if_nameindex, if_nameindex)

socket/if_nametoindex.c

@@ -8,22 +8,23 @@
 __typeof__(if_nametoindex) __if_nametoindex;
 
 unsigned short 
-if_nametoindex(const char *name)
+__if_nametoindex(const char *name)
 {
 	struct ifreq ifr;
 	int fd, r;
 
 	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
         __set_errno (ENODEV);
         return 0;
-    }
+	}
 	strlcpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
 	r = ioctl(fd, SIOCGIFINDEX, &ifr);
 	close(fd);
-    if(!r){
-        return ifr.ifr_ifindex;
-    }
-    __set_errno (ENODEV);
+	if(!r){
+		return ifr.ifr_ifindex;
+	}
+	__set_errno (ENODEV);
 	return 0;
 }
+
 weak_alias (__if_nametoindex, if_nametoindex)