X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=src%2Fifspec.c;fp=src%2Fifspec.c;h=c375bcc083c2789f3813760f54ee9668655923ed;hb=06e1018272502e1d15d6d8f32b80fa96420785b8;hp=0000000000000000000000000000000000000000;hpb=8a59994861a17eb92c11553d88631757ee8e63c3;p=util-vserver.git

diff --git a/src/ifspec.c b/src/ifspec.c
new file mode 100644
index 0000000..c375bcc
--- /dev/null
+++ b/src/ifspec.c
@@ -0,0 +1,188 @@
+// $Id: ifspec.c,v 1.1.4.1 2003/11/21 16:01:09 ensc Exp $
+
+// Copyright (C) 2003 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
+// based on ifspec.cc by Jacques Gelinas
+//  
+// 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 2, 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, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+/*
+	Prints the specs of a network device in shell like form
+
+	ADDR=
+	NETMASK=
+	BCAST=
+*/
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <net/if.h>
+
+static void usage()
+{
+	fprintf (stderr,"ifspec version %s\n",VERSION);
+	fprintf (stderr
+		,"ifspec network-device [ ipaddr netmask broadcast ]\n"
+		 "prints device specification in a shell usable way\n");
+	exit (-1);
+}
+
+static int ifconfig_ioctl(
+	int fd,
+	const char *ifname,
+	int cmd,
+	struct ifreq *ifr)
+{
+	strcpy(ifr->ifr_name, ifname);
+	return ioctl(fd, cmd,ifr);
+}
+
+static unsigned long ip_cnv (const char *str)
+{
+	const char *start_str = str;
+	unsigned tb[4];
+	int no = 0;
+	unsigned long ret;
+	  
+	memset (tb,-1,sizeof(tb));
+	while (*str != '\0' && no < 4){
+		if (isdigit(*str)){
+			int val = atoi(str);
+			if (val > 255) break;
+			tb[no++] = val;
+			while (isdigit(*str)) str++;
+			if (*str == '.'){
+				str++;
+			}else{
+				break;
+			}
+		}else{
+			break;
+		}
+	}
+
+	ret = (tb[0] << 24) | (tb[1]<<16) | (tb[2] << 8) | tb[3];
+	if (no != 4 || *str != '\0'){
+		fprintf (stderr,"Invalid IP number or netmask: %s\n",start_str);
+		ret = 0xffffffff;
+	}
+	return ret;
+}
+
+
+/*
+	Fetch the IP number of an interface from the kernel.
+	Assume the device is already available in the kernel
+	Return -1 if any error.
+*/
+int ifconfig_print (
+	const char *ifname,
+	const char *addrstr,
+	const char *maskstr,
+	const char *bcaststr)
+{
+	int ret = -1;
+	int skfd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (skfd != -1){
+		struct ifreq ifr;
+		struct {
+			unsigned long addr;
+			unsigned long mask;
+		} solved = {0,0};
+		if (addrstr != NULL && addrstr[0] != '\0'){
+			printf ("ADDR=%s\n",addrstr);
+			solved.addr = ip_cnv (addrstr);
+		}else if (ifconfig_ioctl(skfd,ifname,SIOCGIFADDR, &ifr) >= 0){
+			struct sockaddr_in *sin = (struct sockaddr_in*)&ifr.ifr_addr;
+			unsigned long addr = ntohl(sin->sin_addr.s_addr);
+			printf ("ADDR=%lu.%lu.%lu.%lu\n"
+				,(addr>>24)&0xff
+				,(addr>>16)&0xff
+				,(addr>>8)&0xff
+				,addr&0xff);
+			solved.addr = addr;
+			ret = 0;
+		}
+		else {
+		  perror("ioctl(SIOCGIFADDR)");
+		}
+		
+		if (maskstr != NULL && maskstr[0] != '\0'){
+			printf ("NETMASK=%s\n",maskstr);
+			solved.mask = ip_cnv (maskstr);
+		}else		if (ifconfig_ioctl(skfd,ifname,SIOCGIFNETMASK, &ifr) >= 0){
+			struct sockaddr_in *sin = (struct sockaddr_in*)&ifr.ifr_addr;
+			unsigned long addr = ntohl(sin->sin_addr.s_addr);
+			printf ("NETMASK=%lu.%lu.%lu.%lu\n"
+				,(addr>>24)&0xff
+				,(addr>>16)&0xff
+				,(addr>>8)&0xff
+				,addr&0xff);
+			solved.mask = addr;
+			ret = 0;
+		}
+		else {
+		  perror("ioctl(SIOCGIFNETMASK)");
+		}
+		
+		if (bcaststr != NULL && bcaststr[0] != '\0'){
+			printf ("BCAST=%s\n",bcaststr);
+		}else if (ifconfig_ioctl(skfd,ifname,SIOCGIFBRDADDR, &ifr) >= 0){
+			struct sockaddr_in *sin = (struct sockaddr_in*)&ifr.ifr_addr;
+			unsigned long addr = ntohl(sin->sin_addr.s_addr);
+			printf ("BCAST=%lu.%lu.%lu.%lu\n"
+				,(addr>>24)&0xff
+				,(addr>>16)&0xff
+				,(addr>>8)&0xff
+				,addr&0xff);
+			ret = 0;
+		}else if (solved.addr!=0 && solved.mask!=0) {
+			// Can't get it from the kernel, compute it from the IP
+			// and the netmask
+			unsigned long addr = (solved.addr & solved.mask)
+				| ~solved.mask;
+			printf ("BCAST=%lu.%lu.%lu.%lu\n"
+				,(addr>>24)&0xff
+				,(addr>>16)&0xff
+				,(addr>>8)&0xff
+				,addr&0xff);
+			
+		}
+		close (skfd);
+	}
+	return ret;
+}
+
+
+int main (int argc, char *argv[])
+{
+	int ret = -1;
+	if (argc < 2){
+		usage();
+	}else{
+		const char *addrstr = argc >= 3 ? argv[2] : NULL;
+		const char *maskstr = argc >= 4 ? argv[3] : NULL;
+		const char *bcaststr = argc >= 5 ? argv[4] : NULL;
+		ret = ifconfig_print (argv[1],addrstr,maskstr,bcaststr);
+	}
+	return ret;
+}
+
+
+