implemented printing and up/down of simple interfaces

2 files changed, 200 insertions, 4 deletions

diff --git a/README b/README
index 295c21a..24f0c06 100644
--- a/README
+++ b/README
@@ -8,7 +8,9 @@ Currently it contains the following:
 - a simple 'hexdump'
 - a 'fdisk' (but we have to decide for which kind of partition types
   and what kind of operations, could be too big)
-- a 'ifconfig'
+- a 'ifconfig': show and configure simple interfaces
+- a 'ping': test a network connection
+- a 'netstat': see list of active connections of a machine
 
 Note: abase is a shameless copy of sbase/ubase in certain areas like
 the Makefile, libutil, etc. This might also make an integration into
diff --git a/ifconfig.c b/ifconfig.c
index 2d3b8eb..809be95 100644
--- a/ifconfig.c
+++ b/ifconfig.c
@@ -1,26 +1,203 @@
 /* See LICENSE file for copyright and license details. */
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
 #include <net/if.h>
 #include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
 
 #include "util.h"
 
 static void
 usage(void)
 {
-	eprintf("usage: %s [-a]\n", argv0);
+	eprintf("usage: %s [-a] [<interface>] [up|down]\n", argv0);
 }
 
+#ifndef IFF_LOWER_UP
+#define IFF_LOWER_UP 1<<16
+#endif
+#ifndef IFF_DORMANT
+#define IFF_DORMANT 1<<17
+#endif
+#ifndef IFF_ECHO
+#define IFF_ECHO 1<<18
+#endif
+
 static void
 print_interface(char *name)
 {
-	printf("%s\n", name);
+	int fd;
+	struct ifreq ifr;
+	int first;
+	
+	fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (fd < 0) {
+		weprintf("error in socket(AF_INTER, SOCK_DGRAM, 0) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
+
+	strncpy(ifr.ifr_name, name, IF_NAMESIZE);
+	if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
+		close(fd);
+		weprintf("error in ioctl(SIOCGIFFLAGS) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
+
+	printf("%s: flags=%d<", name, ifr.ifr_flags);
+	
+	if (ifr.ifr_flags == 0) {
+		printf(">");
+	} else {
+		first = 1;		
+		if (ifr.ifr_flags & IFF_UP) {
+			printf("%sUP", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_BROADCAST) {
+			printf("%sBROADCAST", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_DEBUG) {
+			printf("%sDEBUG", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_LOOPBACK) {
+			printf("%sLOOPBACK", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_POINTOPOINT) {
+			printf("%sPOINTOPOINT", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_RUNNING) {
+			printf("%sRUNNING", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_NOARP) {
+			printf("%sNOARP", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_PROMISC) {
+			printf("%sPROMISC", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_NOTRAILERS) {
+			printf("%sNOTRAILERS", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_ALLMULTI) {
+			printf("%sALLMULTI", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_MASTER) {
+			printf("%sMASTER", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_SLAVE) {
+			printf("%sSLAVE", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_MULTICAST) {
+			printf("%sMULTICAST", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_PORTSEL) {
+			printf("%sPORTSEL", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_AUTOMEDIA) {
+			printf("%sAUTOMEDIA", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_DYNAMIC) {
+			printf("%sDYNAMIC", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_LOWER_UP) {
+			printf("%sLOWER_UP", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_DORMANT) {
+			printf("%sDORMANT", !first ? "," : ""); first = 0;
+		}
+		if (ifr.ifr_flags & IFF_ECHO) {
+			printf("%sECHO", !first ? "," : ""); first = 0;
+		}
+		printf(">");
+	}
+
+	if (ioctl(fd, SIOCGIFMTU, &ifr) < 0) {
+		close(fd);
+		weprintf("error in ioctl(SIOCGIFMTU) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
+ 	printf("  mtu %d\n", ifr.ifr_mtu);
+
+	char ip_addr[INET_ADDRSTRLEN];
+	if (ioctl(fd, SIOCGIFADDR, &ifr) == 0) {
+		struct sockaddr_in* addr = (struct sockaddr_in*)&ifr.ifr_addr;
+		inet_ntop(AF_INET, &addr->sin_addr, ip_addr, INET_ADDRSTRLEN);
+	} else {
+		ip_addr[0] = '\0';
+	}
+	
+	char ip_netmask[INET_ADDRSTRLEN];
+	if (ioctl(fd, SIOCGIFNETMASK, &ifr) == 0) {
+		struct sockaddr_in* netmask = (struct sockaddr_in*)&ifr.ifr_netmask;
+		inet_ntop(AF_INET, &netmask->sin_addr, ip_netmask, INET_ADDRSTRLEN);
+	} else {
+		ip_netmask[0] = '\0';
+	}
+
+	char ip_broadcast[INET_ADDRSTRLEN];
+	if (ioctl(fd, SIOCGIFBRDADDR, &ifr) == 0) {
+		struct sockaddr_in* broadcast = (struct sockaddr_in*)&ifr.ifr_broadaddr;
+		inet_ntop(AF_INET, &broadcast->sin_addr, ip_broadcast, INET_ADDRSTRLEN);
+	} else {
+		ip_broadcast[0] = '\0';
+	}
+	
+	char ip_hwaddr[32];
+	if (ioctl(fd, SIOCGIFHWADDR, &ifr) == 0) {
+		memcpy(ip_hwaddr, ifr.ifr_hwaddr.sa_data, 8);
+	} else {
+		memset(ip_hwaddr, 0, 32);
+	}
+
+	printf("        inet %s  netmask %s  broadcast %s\n",
+	       ip_addr, ip_netmask, ip_broadcast);
+	printf("        ether ");
+	first = 1;
+	for (int i = 0; i <6; i++) {
+		printf("%s%02x", ( !first ) ? ":" : "", ip_hwaddr[i] & 0xFF); first = 0;
+	}
+	puts("");
+
+	close(fd);
+}
+
+static void
+set_up_down(char *name, int up)
+{
+	int fd;
+	struct ifreq ifr;
+	
+	fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (fd < 0) {
+		weprintf("error in socket(AF_INTER, SOCK_DGRAM, 0) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
+
+	strncpy(ifr.ifr_name, name, IF_NAMESIZE);
+	if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
+		close(fd);
+		weprintf("error in ioctl(SIOCGIFFLAGS) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
+	
+	if (up) {
+		ifr.ifr_flags |= IFF_UP;
+	} else  {
+		ifr.ifr_flags &= ~IFF_UP;
+	}
+
+	if (ioctl(fd, SIOCSIFFLAGS, &ifr) < 0) {
+		close(fd);
+		weprintf("error in ioctl(SIOCGIFFLAGS) on interface '%s': %s\n", name, strerror(errno));
+		return;
+	}
 }
 
 int
 main(int argc, char *argv[])
 {
 	int show_all = 0;
-	//~ struct ifreq ifr;
 	
 	ARGBEGIN {
 	case 'a':
@@ -42,5 +219,22 @@ main(int argc, char *argv[])
 		}
 	}
 	
+	if (argc == 1) {
+		print_interface(argv[0]);
+	} else if (argc == 2) {
+		int up;
+		if (strcmp(argv[1], "up") == 0) {
+			up = 1;
+		} else if (strcmp(argv[1], "down") == 0) {
+			up = 0;
+		} else {
+			weprintf("Expecting 'up' or 'down'\n");
+			usage();
+		}
+		set_up_down(argv[0], up);
+	} else {
+		usage();
+	}
+	
 	return 0;
 }