Reorganize the list of addresses associated with an interface and group them

based on the address family. This should help to recognize interfaces with
multiple AF (e.g. ipv4 and ipv6) with many aliases or additional addresses. The
order of addresses inside a single group is strictly preserved.

Improve the scope_id output for AF_INET6 families, as the
current approach uses hexadecimal string that is basically the ID of an
interface, whilst this information is already depicted by getnameinfo(3) call.
Therefore, now ifconfig just prints the scope of address as it is defined in
2.4 of RFC 2373.

PR:		197270
Approved by:	bapt
MFC after:	2 weeks

sbin/ifconfig/af_inet6.c

@@ -166,6 +166,33 @@ setip6eui64(const char *cmd, int dummy __unused, int s,
 	freeifaddrs(ifap);
 }
 
+static void
+in6_print_scope(uint8_t *a) 
+{
+	const char *sname = NULL;
+	uint16_t val;
+
+	val = (a[0] << 4) + ((a[1] & 0xc0) >> 4);
+
+	if ((val & 0xff0) == 0xff0)
+		sname = "Multicast";
+	else {
+		switch(val) {
+			case 0xfe8:
+				sname = "Link";
+				break;
+			case 0xfec:
+				sname = "Site";
+				break;
+			default:
+				sname = "Global";
+				break;
+		}
+	}
+
+	printf("scope: %s ", sname);
+}
+
 static void
 in6_status(int s __unused, const struct ifaddrs *ifa)
 {
@@ -257,9 +284,7 @@ in6_status(int s __unused, const struct ifaddrs *ifa)
 	if ((flags6 & IN6_IFF_PREFER_SOURCE) != 0)
 		printf("prefer_source ");
 
-	if (((struct sockaddr_in6 *)(ifa->ifa_addr))->sin6_scope_id)
-		printf("scopeid 0x%x ",
-		    ((struct sockaddr_in6 *)(ifa->ifa_addr))->sin6_scope_id);
+	in6_print_scope((uint8_t *)&((struct sockaddr_in6 *)(ifa->ifa_addr))->sin6_addr);
 
 	if (ip6lifetime && (lifetime.ia6t_preferred || lifetime.ia6t_expire)) {
 		printf("pltime ");

sbin/ifconfig/ifconfig.c

@@ -47,6 +47,7 @@ static const char rcsid[] =
 #include <sys/time.h>
 #include <sys/module.h>
 #include <sys/linker.h>
+#include <sys/queue.h>
 
 #include <net/ethernet.h>
 #include <net/if.h>
@@ -110,6 +111,15 @@ static void af_other_status(int);
 
 static struct option *opts = NULL;
 
+struct ifa_order_elt {
+	int if_order;
+	int af_orders[255];
+	struct ifaddrs *ifa;
+	TAILQ_ENTRY(ifa_order_elt) link;
+};
+
+TAILQ_HEAD(ifa_queue, ifa_order_elt);
+
 void
 opt_register(struct option *p)
 {
@@ -141,16 +151,162 @@ usage(void)
 	exit(1);
 }
 
+static int
+calcorders(struct ifaddrs *ifa, struct ifa_queue *q)
+{
+	unsigned int ord, af, ifa_ord;
+	struct ifaddrs *prev;
+	struct ifa_order_elt *cur;
+
+	prev = NULL;
+	cur = NULL;
+	ord = 0;
+	ifa_ord = 0;
+
+	while (ifa != NULL) {
+		if (prev == NULL || strcmp(ifa->ifa_name, prev->ifa_name) != 0) {
+			cur = calloc(1, sizeof(*cur));
+
+			if (cur == NULL)
+				return (-1);
+
+			TAILQ_INSERT_TAIL(q, cur, link);
+			cur->if_order = ifa_ord ++;
+			cur->ifa = ifa;
+			ord = 0;
+		}
+
+		if (ifa->ifa_addr) {
+			af = ifa->ifa_addr->sa_family;
+
+			if (af < sizeof(cur->af_orders) / sizeof(cur->af_orders[0]) && 
+			  cur->af_orders[af] == 0)
+				cur->af_orders[af] = ++ord;
+		}
+		prev = ifa;
+		ifa = ifa->ifa_next;	
+	}
+
+	return (0);
+}
+
+static int
+cmpifaddrs(struct ifaddrs *a, struct ifaddrs *b, struct ifa_queue *q)
+{
+	int ret;
+	unsigned int af1, af2;
+	struct ifa_order_elt *cur, *e1, *e2;
+
+	e1 = e2 = NULL;
+
+	ret = strcmp(a->ifa_name, b->ifa_name);
+	if (ret != 0) {
+		/* We need to find elements corresponding to these different names */
+		TAILQ_FOREACH(cur, q, link) {
+			if (e1 && e2)
+				break;
+
+			if (strcmp(cur->ifa->ifa_name, a->ifa_name) == 0)
+				e1 = cur;
+			else if (strcmp(cur->ifa->ifa_name, b->ifa_name) == 0)
+				e2 = cur;
+		}
+
+		if (!e1 || !e2)
+			return (0);
+		else
+			return (e1->if_order - e2->if_order);
+
+	} else if (a->ifa_addr != NULL && b->ifa_addr != NULL) {
+		TAILQ_FOREACH(cur, q, link) {
+			if (strcmp(cur->ifa->ifa_name, a->ifa_name) == 0) {
+				e1 = cur;
+				break;
+			}
+		}
+
+		if (!e1)
+			return (0);
+
+		af1 = a->ifa_addr->sa_family;
+		af2 = b->ifa_addr->sa_family;
+
+		if (af1 < sizeof(e1->af_orders) / sizeof(e1->af_orders[0]) && 
+		  af2 < sizeof(e1->af_orders) / sizeof(e1->af_orders[0]))
+			return (e1->af_orders[af2] - e1->af_orders[af1]);
+	}
+
+	return (0);
+}
+
+static struct ifaddrs *
+sortifaddrs(struct ifaddrs *list,
+	int (*compare)(struct ifaddrs *, struct ifaddrs *, struct ifa_queue *),
+	struct ifa_queue *q)
+{
+
+	struct ifaddrs *right, *temp, *last, *result, *next, *tail;
+	
+	right = list;
+	temp = list;
+	last = list;
+	result = NULL;
+	next = NULL;
+	tail = NULL;
+
+	if (!list || !list->ifa_next)
+		return (list);
+
+	while (temp && temp->ifa_next) {
+		last = right;
+		right = right->ifa_next;
+		temp = temp->ifa_next->ifa_next;
+	}
+
+	last->ifa_next = NULL;
+
+	list = sortifaddrs(list, compare, q);
+	right = sortifaddrs(right, compare, q);
+
+	while (list || right) {
+
+		if (!right) {
+			next = list;
+			list = list->ifa_next;
+		} else if (!list) {
+			next = right;
+			right = right->ifa_next;
+		} else if (compare(list, right, q) <= 0) {
+			next = list;
+			list = list->ifa_next;
+		} else {
+			next = right;
+			right = right->ifa_next;
+		}
+
+		if (!result)
+			result = next;
+		else
+			tail->ifa_next = next;
+
+		tail = next;
+	}
+
+	return (result);
+}
+
 int
 main(int argc, char *argv[])
 {
 	int c, all, namesonly, downonly, uponly;
 	const struct afswtch *afp = NULL;
 	int ifindex;
-	struct ifaddrs *ifap, *ifa;
+	struct ifaddrs *ifap, *sifap, *ifa;
 	struct ifreq paifr;
 	const struct sockaddr_dl *sdl;
 	char options[1024], *cp, *namecp = NULL;
+	struct ifa_queue q = TAILQ_HEAD_INITIALIZER(q);
+	struct ifa_order_elt *cur, *tmp;
 	const char *ifname;
 	struct option *p;
 	size_t iflen;
@@ -285,9 +441,19 @@ main(int argc, char *argv[])
 
 	if (getifaddrs(&ifap) != 0)
 		err(EXIT_FAILURE, "getifaddrs");
+
 	cp = NULL;
+	
+	if (calcorders(ifap, &q) != 0)
+		err(EXIT_FAILURE, "calcorders");
+		
+	sifap = sortifaddrs(ifap, cmpifaddrs, &q);
+
+	TAILQ_FOREACH_SAFE(cur, &q, link, tmp)
+		free(cur);
+
 	ifindex = 0;
-	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
+	for (ifa = sifap; ifa; ifa = ifa->ifa_next) {
 		memset(&paifr, 0, sizeof(paifr));
 		strncpy(paifr.ifr_name, ifa->ifa_name, sizeof(paifr.ifr_name));
 		if (sizeof(paifr.ifr_addr) >= ifa->ifa_addr->sa_len) {