path: root/meta/recipes-extended/iputils/files/arping-break-libsysfs-dependency.patch

arping: Break libsysfs dependency

Port Fedora 17's iputils-20071127-infiniband.patch, which inlines sysfs
access previously done by libsysfs (which is in /usr, and thus not
usable by /bin/arping).

Upstream-Status: Inappropriate [not author] 
Signed-off-by: Andy Ross <andy.ross@windriver.com>
---
 Makefile |    2 +-
 arping.c |  152 ++++++++++++++++++++++++++++++++++++++++++++------------------
 2 files changed, 109 insertions(+), 45 deletions(-)

diff --git a/Makefile b/Makefile
index d9a5ca5..943f048 100644
--- a/Makefile
+++ b/Makefile
@@ -27,7 +27,7 @@ all: $(TARGETS)
 
 
 tftpd: tftpd.o tftpsubs.o
-arping: arping.o -lsysfs
+arping: arping.o
 ping: ping.o ping_common.o
 ping6: ping6.o ping_common.o -lresolv -lcrypto
 ping.o ping6.o ping_common.o: ping_common.h
diff --git a/arping.c b/arping.c
index 13484de..6379354 100644
--- a/arping.c
+++ b/arping.c
@@ -32,8 +32,6 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-#include <sysfs/libsysfs.h>
-
 #include "SNAPSHOT.h"
 
 static void usage(void) __attribute__((noreturn));
@@ -52,14 +50,22 @@ int unicasting;
 int s;
 int broadcast_only;
 
-struct sockaddr_storage me;
-struct sockaddr_storage he;
+struct sockaddr_ll *me=NULL;
+struct sockaddr_ll *he=NULL;
 
 struct timeval start, last;
 
 int sent, brd_sent;
 int received, brd_recv, req_recv;
 
+#define SYSFS_MNT_PATH          "/sys"
+#define SYSFS_CLASS             "class"
+#define SYSFS_NET               "net"
+#define SYSFS_BROADCAST         "broadcast"
+#define SYSFS_PATH_ENV          "SYSFS_PATH"
+#define SYSFS_PATH_LEN          256
+#define SOCKADDR_LEN		(2 * sizeof(struct sockaddr_ll))
+
 #define MS_TDIFF(tv1,tv2) ( ((tv1).tv_sec-(tv2).tv_sec)*1000 + \
 			   ((tv1).tv_usec-(tv2).tv_usec)/1000 )
 
@@ -166,6 +172,10 @@ void finish(void)
 		printf("\n");
 		fflush(stdout);
 	}
+
+	free(me);
+	free(he);
+
 	if (dad)
 		exit(!!received);
 	if (unsolicited)
@@ -189,8 +199,7 @@ void catcher(void)
 		finish();
 
 	if ( count!=0  && (last.tv_sec==0 || MS_TDIFF(tv,last) > 500 ) ) {
-		send_pack(s, src, dst,
-			  (struct sockaddr_ll *)&me, (struct sockaddr_ll *)&he);
+		send_pack(s, src, dst, me, he);
 		if (count >= 0)
 		    count--;
 		if (count == 0 && unsolicited)
@@ -239,7 +248,7 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 		return 0;
 	if (ah->ar_pln != 4)
 		return 0;
-	if (ah->ar_hln != ((struct sockaddr_ll *)&me)->sll_halen)
+	if (ah->ar_hln != me->sll_halen)
 		return 0;
 	if (len < sizeof(*ah) + 2*(4 + ah->ar_hln))
 		return 0;
@@ -250,7 +259,7 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 			return 0;
 		if (src.s_addr != dst_ip.s_addr)
 			return 0;
-		if (memcmp(p+ah->ar_hln+4, ((struct sockaddr_ll *)&me)->sll_addr, ah->ar_hln))
+		if (memcmp(p+ah->ar_hln+4, me->sll_addr, ah->ar_hln))
 			return 0;
 	} else {
 		/* DAD packet was:
@@ -268,7 +277,7 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 		 */
 		if (src_ip.s_addr != dst.s_addr)
 			return 0;
-		if (memcmp(p, ((struct sockaddr_ll *)&me)->sll_addr, ((struct sockaddr_ll *)&me)->sll_halen) == 0)
+		if (memcmp(p, me->sll_addr, me->sll_halen) == 0)
 			return 0;
 		if (src.s_addr && src.s_addr != dst_ip.s_addr)
 			return 0;
@@ -284,7 +293,7 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 			printf("for %s ", inet_ntoa(dst_ip));
 			s_printed = 1;
 		}
-		if (memcmp(p+ah->ar_hln+4, ((struct sockaddr_ll *)&me)->sll_addr, ah->ar_hln)) {
+		if (memcmp(p+ah->ar_hln+4, me->sll_addr, ah->ar_hln)) {
 			if (!s_printed)
 				printf("for ");
 			printf("[");
@@ -310,40 +319,67 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
 	if (quit_on_reply)
 		finish();
 	if(!broadcast_only) {
-		memcpy(((struct sockaddr_ll *)&he)->sll_addr, p, ((struct sockaddr_ll *)&me)->sll_halen);
+		memcpy(he->sll_addr, p, me->sll_halen);
 		unicasting=1;
 	}
 	return 1;
 }
 
-void set_device_broadcast(char *device, unsigned char *ba, size_t balen)
+int get_sysfs_mnt_path(char *mnt_path, size_t len)
 {
-	struct sysfs_class_device *dev;
-	struct sysfs_attribute *brdcast;
-	unsigned char *p;
-	int ch;
+        const char *sysfs_path_env;
+        int pth_len=0;
 
-	dev = sysfs_open_class_device("net", device);
-	if (!dev) {
-		perror("sysfs_open_class_device(net)");
-		exit(2);
-	}
+        if (len == 0 || mnt_path == NULL)
+                return -1;
 
-	brdcast = sysfs_get_classdev_attr(dev, "broadcast");
-	if (!brdcast) {
-		perror("sysfs_get_classdev_attr(broadcast)");
-		exit(2);
-	}
+        /* possible overrride of real mount path */
+        sysfs_path_env = getenv(SYSFS_PATH_ENV);
+        memset(mnt_path, 0, len);
+        strncpy(mnt_path,
+                sysfs_path_env != NULL ? sysfs_path_env : SYSFS_MNT_PATH,
+                len-1);
 
-	if (sysfs_read_attribute(brdcast)) {
-		perror("sysfs_read_attribute");
-		exit(2);
-	}
+        if ((pth_len = strlen(mnt_path)) > 0 && mnt_path[pth_len-1] == '/')
+                mnt_path[pth_len-1] = '\0';
+
+        return 0;
+}
+
+int make_sysfs_broadcast_path(char *broadcast_path, size_t len)
+{
+        char mnt_path[SYSFS_PATH_LEN];
+
+        if (get_sysfs_mnt_path(mnt_path, len) != 0)
+                return -1;
 
-	for (p = ba, ch = 0; p < ba + balen; p++, ch += 3)
-		*p = strtoul(brdcast->value + ch, NULL, 16);
+        snprintf(broadcast_path, len,
+                "%s/" SYSFS_CLASS "/" SYSFS_NET "/%s/" SYSFS_BROADCAST,
+                mnt_path, device);
 
-	return;
+        return 0;
+}
+
+char * read_sysfs_broadcast(char *brdcast_path)
+{
+        int fd;
+        int len_to_read;
+        char *brdcast = NULL;
+
+        if ((fd = open(brdcast_path, O_RDONLY)) > -1) {
+                len_to_read = lseek(fd, 0L, SEEK_END);
+                if ((brdcast = malloc(len_to_read+1)) != NULL) {
+                        lseek(fd, 0L, SEEK_SET);
+                        memset(brdcast, 0, len_to_read+1);
+                        if (read(fd, brdcast, len_to_read) == -1) {
+                                free(brdcast);
+                                brdcast = NULL;
+                        }
+                }
+                close(fd);
+        }
+
+        return brdcast;
 }
 
 int
@@ -361,6 +397,17 @@ main(int argc, char **argv)
 		exit(-1);
 	}
 
+	me = malloc(SOCKADDR_LEN);
+	if (!me) {
+		fprintf(stderr, "arping: could not allocate memory\n");
+		exit(1);
+	}
+	he = malloc(SOCKADDR_LEN);
+	if (!he) {
+		fprintf(stderr, "arping: could not allocate memory\n");
+		exit(1);
+	}
+
 	while ((ch = getopt(argc, argv, "h?bfDUAqc:w:s:I:V")) != EOF) {
 		switch(ch) {
 		case 'b':
@@ -509,34 +556,51 @@ main(int argc, char **argv)
 		close(probe_fd);
 	};
 
-	((struct sockaddr_ll *)&me)->sll_family = AF_PACKET;
-	((struct sockaddr_ll *)&me)->sll_ifindex = ifindex;
-	((struct sockaddr_ll *)&me)->sll_protocol = htons(ETH_P_ARP);
-	if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
+	me->sll_family = AF_PACKET;
+	me->sll_ifindex = ifindex;
+	me->sll_protocol = htons(ETH_P_ARP);
+	if (bind(s, (struct sockaddr*)me, SOCKADDR_LEN) == -1) {
 		perror("bind");
 		exit(2);
 	}
 
 	if (1) {
-		socklen_t alen = sizeof(me);
-		if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
+		socklen_t alen = SOCKADDR_LEN;
+		if (getsockname(s, (struct sockaddr*)me, &alen) == -1) {
 			perror("getsockname");
 			exit(2);
 		}
 	}
-	if (((struct sockaddr_ll *)&me)->sll_halen == 0) {
+	if (me->sll_halen == 0) {
 		if (!quiet)
 			printf("Interface \"%s\" is not ARPable (no ll address)\n", device);
 		exit(dad?0:2);
 	}
 
-	he = me;
+	memcpy(he, me, SOCKADDR_LEN);
 
 #if 1
-	set_device_broadcast(device, ((struct sockaddr_ll *)&he)->sll_addr,
-			     ((struct sockaddr_ll *)&he)->sll_halen);
+	char brdcast_path[SYSFS_PATH_LEN];
+	char *brdcast_val=NULL;
+	char *next_ch;
+
+	if (make_sysfs_broadcast_path(brdcast_path, sizeof brdcast_path) != 0) {
+		perror("sysfs attribute broadcast");
+		exit(2);
+	}
+
+	if ((brdcast_val = read_sysfs_broadcast(brdcast_path)) == NULL) {
+		perror("sysfs read broadcast value");
+		exit(2);
+	}
+
+	for (ch=0; ch<he->sll_halen; ch++) {
+		he->sll_addr[ch] = strtol(brdcast_val + (ch*3), &next_ch, 16);
+	}
+
+	free(brdcast_val);
 #else
-	memset(((struct sockaddr_ll *)&he)->sll_addr, -1, ((struct sockaddr_ll *)&he)->sll_halen);
+	memset(he->sll_addr, -1, he->sll_halen);
 #endif
 
 	if (!quiet) {
-- 
1.7.10.4