Tools: hv: Prepare to expand kvp_get_ip_address() functionality

kvp_get_ip_address() implemented the functionality to retrieve IP address info.
Make this function more generic so that we could retrieve additional
per-interface information.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/hv/hv_kvp_daemon.c

@@ -492,7 +492,8 @@ void kvp_get_os_info(void)
 }
 
 static int
-kvp_get_ip_address(int family, char *buffer, int length)
+kvp_get_ip_address(int family, char *if_name, int op,
+		 void  *out_buffer, int length)
 {
 	struct ifaddrs *ifap;
 	struct ifaddrs *curp;
@@ -502,10 +503,19 @@ kvp_get_ip_address(int family, char *buffer, int length)
 	const char *str;
 	char tmp[50];
 	int error = 0;
+	char *buffer;
+	struct hv_kvp_ipaddr_value *ip_buffer;
 
+	if (op == KVP_OP_ENUMERATE) {
+		buffer = out_buffer;
+	} else {
+		ip_buffer = out_buffer;
+		buffer = (char *)ip_buffer->ip_addr;
+		ip_buffer->addr_family = 0;
+	}
 	/*
 	 * On entry into this function, the buffer is capable of holding the
-	 * maximum key value (2048 bytes).
+	 * maximum key value.
 	 */
 
 	if (getifaddrs(&ifap)) {
@@ -515,14 +525,43 @@ kvp_get_ip_address(int family, char *buffer, int length)
 
 	curp = ifap;
 	while (curp != NULL) {
-		if ((curp->ifa_addr != NULL) &&
-		   (curp->ifa_addr->sa_family == family)) {
-			if (family == AF_INET) {
+		if (curp->ifa_addr == NULL) {
+			curp = curp->ifa_next;
+			continue;
+		}
+
+		if ((if_name != NULL) &&
+			(strncmp(curp->ifa_name, if_name, strlen(if_name)))) {
+			/*
+			 * We want info about a specific interface;
+			 * just continue.
+			 */
+			curp = curp->ifa_next;
+			continue;
+		}
+
+		/*
+		 * We only support two address families: AF_INET and AF_INET6.
+		 * If a family value of 0 is specified, we collect both
+		 * supported address families; if not we gather info on
+		 * the specified address family.
+		 */
+		if ((family != 0) && (curp->ifa_addr->sa_family != family)) {
+			curp = curp->ifa_next;
+			continue;
+		}
+		if ((curp->ifa_addr->sa_family != AF_INET) &&
+			(curp->ifa_addr->sa_family != AF_INET6)) {
+			curp = curp->ifa_next;
+			continue;
+		}
+
+		if ((curp->ifa_addr->sa_family == AF_INET) &&
+			((family == AF_INET) || (family == 0))) {
 			struct sockaddr_in *addr =
 			(struct sockaddr_in *) curp->ifa_addr;
 
-				str = inet_ntop(family, &addr->sin_addr,
-						tmp, 50);
+			str = inet_ntop(AF_INET, &addr->sin_addr, tmp, 50);
 			if (str == NULL) {
 				strcpy(buffer, "inet_ntop failed\n");
 				error = 1;
@@ -538,7 +577,7 @@ kvp_get_ip_address(int family, char *buffer, int length)
 			if ((length - offset) < (ipv4_len + 1))
 				goto getaddr_done;
 
-			} else {
+		} else if ((family == AF_INET6) || (family == 0)) {
 
 			/*
 			 * We only support AF_INET and AF_INET6
@@ -547,7 +586,7 @@ kvp_get_ip_address(int family, char *buffer, int length)
 			struct sockaddr_in6 *addr =
 				(struct sockaddr_in6 *) curp->ifa_addr;
 
-				str = inet_ntop(family,
+			str = inet_ntop(AF_INET6,
 					&addr->sin6_addr.s6_addr,
 					tmp, 50);
 			if (str == NULL) {
@@ -566,7 +605,7 @@ kvp_get_ip_address(int family, char *buffer, int length)
 
 		}
 
-		}
+
 		curp = curp->ifa_next;
 	}
 
@@ -811,13 +850,13 @@ int main(void)
 			strcpy(key_value, lic_version);
 			break;
 		case NetworkAddressIPv4:
-			kvp_get_ip_address(AF_INET, key_value,
-					HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
+			kvp_get_ip_address(AF_INET, NULL, KVP_OP_ENUMERATE,
+				key_value, HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
 			strcpy(key_name, "NetworkAddressIPv4");
 			break;
 		case NetworkAddressIPv6:
-			kvp_get_ip_address(AF_INET6, key_value,
-					HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
+			kvp_get_ip_address(AF_INET6, NULL, KVP_OP_ENUMERATE,
+				key_value, HV_KVP_EXCHANGE_MAX_VALUE_SIZE);
 			strcpy(key_name, "NetworkAddressIPv6");
 			break;
 		case OSBuildNumber: