pppd: Combine get_first_ethernet() and get_if_hwaddr() into one function (#207)

On all places is just needed hardware address for the first ethernet-style
interface. So provide it by new get_first_ether_hwaddr() function.

Signed-off-by: Pali Rohár <pali@kernel.org>

Author: pali

pppd/ipv6cp.c

@@ -1068,18 +1068,10 @@ static int
 ether_to_eui64(eui64_t *p_eui64)
 {
     u_char addr[6];
-    char *if_name;
-
-    if (get_if_hwaddr(addr, devnam) < 0) {
-        if ((if_name = get_first_ethernet()) == NULL) {
-            error("no persistent id can be found");
-            return 0;
-        }
-
-        if (get_if_hwaddr(addr, if_name) < 0) {
-            error("could not obtain hardware address for %s", if_name);
-            return 0;
-        }
+
+    if (get_if_hwaddr(addr, devnam) < 0 || get_first_ether_hwaddr(addr) < 0) {
+        error("ipv6cp: no persistent id can be found");
+        return 0;
     }
 
     /*

pppd/multilink.c

@@ -430,13 +430,11 @@ owns_unit(TDB_DATA key, int unit)
 static int
 get_default_epdisc(struct epdisc *ep)
 {
-	char *p;
 	struct hostent *hp;
 	u_int32_t addr;
 
 	/* First try for an ethernet MAC address */
-	p = get_first_ethernet();
-	if (p != 0 && get_if_hwaddr(ep->value, p) >= 0) {
+	if (get_first_ether_hwaddr(ep->value) >= 0) {
 		ep->class = EPD_MAC;
 		ep->length = 6;
 		return 1;

pppd/pppd.h

@@ -710,7 +710,7 @@ int  sipxfaddr(int, unsigned long, unsigned char *);
 int  cipxfaddr(int);
 #endif
 int  get_if_hwaddr(u_char *addr, char *name);
-char *get_first_ethernet(void);
+int  get_first_ether_hwaddr(u_char *addr);
 int get_time(struct timeval *);
 				/* Get current time, monotonic if possible. */
 

pppd/sys-linux.c

@@ -2159,46 +2159,43 @@ get_if_hwaddr(u_char *addr, char *name)
 }
 
 /*
- * get_first_ethernet - return the name of the first ethernet-style
- * interface on this system.
+ * get_first_ether_hwaddr - get the hardware address for the first
+ * ethernet-style interface on this system.
  */
-static char first_ether_name[IF_NAMESIZE];
-char *
-get_first_ethernet(void)
+int
+get_first_ether_hwaddr(u_char *addr)
 {
 	struct if_nameindex *if_ni, *i;
 	struct ifreq ifreq;
 	int ret, sock_fd;
 
 	sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
 	if (sock_fd < 0)
-		return NULL;
+		return -1;
 
 	if_ni = if_nameindex();
 	if (!if_ni) {
 		close(sock_fd);
-		return NULL;
+		return -1;
 	}
 
-	first_ether_name[0] = 0;
+	ret = -1;
 
 	for (i = if_ni; !(i->if_index == 0 && i->if_name == NULL); i++) {
 		memset(&ifreq.ifr_hwaddr, 0, sizeof(struct sockaddr));
 		strlcpy(ifreq.ifr_name, i->if_name, sizeof(ifreq.ifr_name));
 		ret = ioctl(sock_fd, SIOCGIFHWADDR, &ifreq);
 		if (ret >= 0 && ifreq.ifr_hwaddr.sa_family == ARPHRD_ETHER) {
-			strlcpy(first_ether_name, i->if_name, sizeof(first_ether_name));
+			memcpy(addr, ifreq.ifr_hwaddr.sa_data, 6);
 			break;
 		}
+		ret = -1;
 	}
 
 	if_freenameindex(if_ni);
 	close(sock_fd);
 
-	if (!first_ether_name[0])
-		return NULL;
-
-	return first_ether_name;
+	return ret;
 }
 
 /********************************************************************

pppd/sys-solaris.c

@@ -218,10 +218,7 @@ static int	if6_is_up = 0;	/* IPv6 interface has been marked up */
 
 #endif /* defined(INET6) && defined(SOL2) */
 
-#if defined(INET6) && defined(SOL2)
-static char	first_ether_name[LIFNAMSIZ];	/* Solaris 8 and above */
-#else
-static char	first_ether_name[IFNAMSIZ];	/* Before Solaris 8 */
+#if !defined(INET6) || !defined(SOL2)
 #define MAXIFS		256			/* Max # of interfaces */
 #endif /* defined(INET6) && defined(SOL2) */
 
@@ -294,13 +291,13 @@ sifppa(fd, ppa)
 
 #if defined(SOL2) && defined(INET6)
 /*
- * get_first_ethernet - returns the first Ethernet interface name found in 
- * the system, or NULL if none is found
+ * get_first_ether_hwaddr - get the hardware address for the first
+ * ethernet-style interface on this system.
  *
  * NOTE: This is the lifreq version (Solaris 8 and above)
  */
-char *
-get_first_ethernet(void)
+int
+get_first_ether_hwaddr(u_char *addr)
 {
     struct lifnum lifn;
     struct lifconf lifc;
@@ -312,7 +309,7 @@ get_first_ethernet(void)
 
     fd = socket(AF_INET, SOCK_DGRAM, 0);
     if (fd < 0) {
-	return 0;
+	return -1;
     }
 
     /*
@@ -323,7 +320,7 @@ get_first_ethernet(void)
     if (ioctl(fd, SIOCGLIFNUM, &lifn) < 0) {
 	close(fd);
 	error("could not determine number of interfaces: %m");
-	return 0;
+	return -1;
     }
 
     num_ifs = lifn.lifn_count;
@@ -332,7 +329,7 @@ get_first_ethernet(void)
     if (req == NULL) {
 	close(fd);
 	error("out of memory");
-	return 0;
+	return -1;
     }
 
     /*
@@ -346,7 +343,7 @@ get_first_ethernet(void)
 	close(fd);
 	free(req);
 	error("SIOCGLIFCONF: %m");
-	return 0;
+	return -1;
     }
 
     /*
@@ -363,38 +360,38 @@ get_first_ethernet(void)
 	memset(&lifr, 0, sizeof(lifr));
 	strncpy(lifr.lifr_name, plifreq->lifr_name, sizeof(lifr.lifr_name));
 	if (ioctl(fd, SIOCGLIFFLAGS, &lifr) < 0) {
-	    close(fd);
-	    free(req);
 	    error("SIOCGLIFFLAGS: %m");
-	    return 0;
+	    break;
 	}
 	fl = lifr.lifr_flags;
 
 	if ((fl & (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|IFF_LOOPBACK|IFF_NOARP))
 		!= (IFF_UP | IFF_BROADCAST))
 	    continue;
 
+	if (get_if_hwaddr(addr, lifr.lifr_name) < 0)
+	    continue;
+
 	found = 1;
 	break;
     }
     free(req);
     close(fd);
 
-    if (found) {
-	strncpy(first_ether_name, lifr.lifr_name, sizeof(first_ether_name));
-	return (char *)first_ether_name;
-    } else
-	return NULL;
+    if (found)
+	return 0;
+    else
+	return -1;
 }
 #else
 /*
- * get_first_ethernet - returns the first Ethernet interface name found in 
- * the system, or NULL if none is found
+ * get_first_ether_hwaddr - get the hardware address for the first
+ * ethernet-style interface on this system.
  *
  * NOTE: This is the ifreq version (before Solaris 8). 
  */
-char *
-get_first_ethernet(void)
+int
+get_first_ether_hwaddr(u_char *addr)
 {
     struct ifconf ifc;
     struct ifreq *pifreq;
@@ -405,7 +402,7 @@ get_first_ethernet(void)
 
     fd = socket(AF_INET, SOCK_DGRAM, 0);
     if (fd < 0) {
-	return 0;
+	return -1;
     }
 
     /*
@@ -420,7 +417,7 @@ get_first_ethernet(void)
     if (req == NULL) {
 	close(fd);
 	error("out of memory");
-	return 0;
+	return -1;
     }
 
     /*
@@ -432,7 +429,7 @@ get_first_ethernet(void)
 	close(fd);
 	free(req);
 	error("SIOCGIFCONF: %m");
-	return 0;
+	return -1;
     }
 
     /*
@@ -449,28 +446,28 @@ get_first_ethernet(void)
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, pifreq->ifr_name, sizeof(ifr.ifr_name));
 	if (ioctl(fd, SIOCGIFFLAGS, &ifr) < 0) {
-	    close(fd);
-	    free(req);
 	    error("SIOCGIFFLAGS: %m");
-	    return 0;
+	    break;
 	}
 	fl = ifr.ifr_flags;
 
 	if ((fl & (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|IFF_LOOPBACK|IFF_NOARP))
 		!= (IFF_UP | IFF_BROADCAST))
 	    continue;
 
+	if (get_if_hwaddr(addr, ifr.ifr_name) < 0)
+	    continue;
+
 	found = 1;
 	break;
     }
     free(req);
     close(fd);
 
-    if (found) {
-	strncpy(first_ether_name, ifr.ifr_name, sizeof(first_ether_name));
-	return (char *)first_ether_name;
-    } else
-	return NULL;
+    if (found)
+	return 0;
+    else
+	return -1;
 }
 #endif /* defined(SOL2) && defined(INET6) */