[PATCH iproute2-next v7 1/1] iproute: Extend bonding's "arp_ip_target" parameter to add vlan tags.

[David Wilder <wilder@us.ibm.com>]

This change extends the "arp_ip_target" parameter format to allow for
a list of vlan tags to be included for each arp target.

The new format for arp_ip_target is:
arp_ip_target=ipv4-address[vlan-tag\...],...

Examples:
arp_ip_target=10.0.0.1[10]
arp_ip_target=10.0.0.1[100/200]

The inclusion of the list of vlan tags is optional. The new logic
preserves both forward and backward compatibility with the kernel
and iproute2 versions.

Signed-off-by: David Wilder <wilder@us.ibm.com>
---
 ip/iplink_bond.c | 149 ++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 123 insertions(+), 26 deletions(-)

diff --git a/ip/iplink_bond.c b/ip/iplink_bond.c
index d6960f6d..0f34125d 100644
--- a/ip/iplink_bond.c
+++ b/ip/iplink_bond.c
@@ -173,6 +173,55 @@ static void explain(void)
 	print_explain(stderr);
 }
 
+#define BOND_VLAN_PROTO_NONE htons(0xffff)
+#define BOND_MAX_VLAN_TAGS 5
+#define VLAN_VID_MASK 0x0fff
+
+struct bond_vlan_tag {
+	__be16  vlan_proto;
+	__be16  vlan_id;
+};
+
+static struct bond_vlan_tag *bond_vlan_tags_parse(char *vlan_list, int level, int *size)
+{
+	struct bond_vlan_tag *tags = NULL;
+	char *vlan;
+	int n;
+
+	if (level > BOND_MAX_VLAN_TAGS) {
+		fprintf(stderr, "Error: Too many vlan tags specified, maximum is %d.\n",
+			BOND_MAX_VLAN_TAGS);
+		exit(1);
+	}
+
+	if (!vlan_list || strlen(vlan_list) == 0) {
+		tags = calloc(level + 1, sizeof(*tags));
+		*size = (level + 1) * (sizeof(*tags));
+		if (tags)
+			tags[level].vlan_proto = BOND_VLAN_PROTO_NONE;
+		return tags;
+	}
+
+	for (vlan = strsep(&vlan_list, "/"); (vlan != 0); level++) {
+		tags = bond_vlan_tags_parse(vlan_list, level + 1, size);
+		if (!tags)
+			continue;
+
+		tags[level].vlan_proto = htons(ETH_P_8021Q);
+		n = sscanf(vlan, "%hu", &(tags[level].vlan_id));
+
+		if (n != 1 || tags[level].vlan_id < 1 || tags[level].vlan_id >= VLAN_VID_MASK) {
+			fprintf(stderr, "Error: Invalid vlan_id specified: %hu\n",
+				tags[level].vlan_id);
+			exit(1);
+		}
+
+		return tags;
+	}
+
+	return NULL;
+}
+
 static int bond_parse_opt(struct link_util *lu, int argc, char **argv,
 			  struct nlmsghdr *n)
 {
@@ -239,12 +288,28 @@ static int bond_parse_opt(struct link_util *lu, int argc, char **argv,
 				NEXT_ARG();
 				char *targets = strdupa(*argv);
 				char *target = strtok(targets, ",");
-				int i;
+				struct bond_vlan_tag *tags;
+				int size, i;
 
 				for (i = 0; target && i < BOND_MAX_ARP_TARGETS; i++) {
-					__u32 addr = get_addr32(target);
-
-					addattr32(n, 1024, i, addr);
+					struct {
+						__u32 addr;
+						struct bond_vlan_tag vlans[];
+					} data;
+					char *vlan_list, *dup;
+
+					dup = strdupa(target);
+					data.addr = get_addr32(strsep(&dup, "["));
+					vlan_list = strsep(&dup, "]");
+
+					if (vlan_list) {
+						tags = bond_vlan_tags_parse(vlan_list, 0, &size);
+						memcpy(&data.vlans, tags, size);
+						addattr_l(n, 1024, i, &data,
+							  sizeof(data.addr)+size);
+					} else {
+						addattr32(n, 1024, i, data.addr);
+					}
 					target = strtok(NULL, ",");
 				}
 				addattr_nest_end(n, nest);
@@ -429,6 +494,22 @@ static int bond_parse_opt(struct link_util *lu, int argc, char **argv,
 	return 0;
 }
 
+static void bond_vlan_tags_print(const struct bond_vlan_tag *vlan)
+{
+	for (unsigned int l = 0; l < BOND_MAX_VLAN_TAGS + 1; l++, vlan++) {
+		if (vlan->vlan_proto == BOND_VLAN_PROTO_NONE)
+			return;
+
+		if (l > 0)
+			print_string(PRINT_FP, NULL, "/", NULL);
+
+		print_uint(PRINT_ANY, NULL, "%u", vlan->vlan_id);
+	}
+
+	fprintf(stderr, "Internal Error: too many vlan tags.\n");
+	exit(1);
+}
+
 static void bond_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 {
 	int i;
@@ -499,24 +580,44 @@ static void bond_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 	if (tb[IFLA_BOND_ARP_IP_TARGET]) {
 		struct rtattr *iptb[BOND_MAX_ARP_TARGETS + 1];
 
-		parse_rtattr_nested(iptb, BOND_MAX_ARP_TARGETS,
-				    tb[IFLA_BOND_ARP_IP_TARGET]);
+		parse_rtattr_nested(iptb, BOND_MAX_ARP_TARGETS, tb[IFLA_BOND_ARP_IP_TARGET]);
 
 		if (iptb[0]) {
 			open_json_array(PRINT_JSON, "arp_ip_target");
 			print_string(PRINT_FP, NULL, "arp_ip_target ", NULL);
 		}
 
-		for (i = 0; i < BOND_MAX_ARP_TARGETS; i++) {
-			if (iptb[i])
-				print_string(PRINT_ANY,
-					     NULL,
-					     "%s",
-					     rt_addr_n2a_rta(AF_INET, iptb[i]));
-			if (!is_json_context()
-			    && i < BOND_MAX_ARP_TARGETS-1
-			    && iptb[i+1])
-				fprintf(f, ",");
+		for (unsigned int i = 0; i < BOND_MAX_ARP_TARGETS && iptb[i]; i++) {
+			struct {
+				__u32 addr;
+				struct bond_vlan_tag vlans[BOND_MAX_VLAN_TAGS + 1];
+			} data;
+
+			if (RTA_PAYLOAD(iptb[i]) < sizeof(data.addr) ||
+				RTA_PAYLOAD(iptb[i]) > sizeof(data)) {
+				fprintf(stderr, "Internal Error: Bad payload for arp_ip_target.\n");
+				exit(1);
+			}
+			memcpy(&data, RTA_DATA(iptb[i]), RTA_PAYLOAD(iptb[i]));
+
+			open_json_object(NULL);
+			print_color_string(PRINT_ANY, COLOR_INET, "addr", "%s",
+					   rt_addr_n2a(AF_INET, sizeof(data.addr), &data.addr));
+
+			if (RTA_PAYLOAD(iptb[i]) > sizeof(data.addr)) {
+				open_json_array(PRINT_JSON, "vlan");
+				print_string(PRINT_FP, NULL, "[", NULL);
+
+				bond_vlan_tags_print(data.vlans);
+
+				close_json_array(PRINT_JSON, NULL);
+				print_string(PRINT_FP, NULL, "]", NULL);
+			}
+
+			if (i < BOND_MAX_ARP_TARGETS - 1 && iptb[i+1])
+				print_string(PRINT_FP, NULL, ",", NULL);
+
+			close_json_object();
 		}
 
 		if (iptb[0]) {
@@ -528,8 +629,7 @@ static void bond_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 	if (tb[IFLA_BOND_NS_IP6_TARGET]) {
 		struct rtattr *ip6tb[BOND_MAX_NS_TARGETS + 1];
 
-		parse_rtattr_nested(ip6tb, BOND_MAX_NS_TARGETS,
-				    tb[IFLA_BOND_NS_IP6_TARGET]);
+		parse_rtattr_nested(ip6tb, BOND_MAX_NS_TARGETS, tb[IFLA_BOND_NS_IP6_TARGET]);
 
 		if (ip6tb[0]) {
 			open_json_array(PRINT_JSON, "ns_ip6_target");
@@ -538,14 +638,11 @@ static void bond_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 
 		for (i = 0; i < BOND_MAX_NS_TARGETS; i++) {
 			if (ip6tb[i])
-				print_string(PRINT_ANY,
-					     NULL,
-					     "%s",
-					     rt_addr_n2a_rta(AF_INET6, ip6tb[i]));
-			if (!is_json_context()
-			    && i < BOND_MAX_NS_TARGETS-1
-			    && ip6tb[i+1])
-				fprintf(f, ",");
+				print_color_string(PRINT_ANY, COLOR_INET6, NULL, "%s",
+						   rt_addr_n2a_rta(AF_INET6, ip6tb[i]));
+
+			if (i < BOND_MAX_NS_TARGETS - 1 && ip6tb[i+1])
+				print_string(PRINT_FP, NULL, ",", NULL);
 		}
 
 		if (ip6tb[0]) {
-- 
2.50.1