tc: flower: support matching flags

Enhance flower to support matching on flags.

The 1st flag allows to match on whether the packet is
an IP fragment.

Example:

	# add a flower filter that will drop fragmented packets
	# (bit 0 of control flags)
	tc filter add dev ens4f0 protocol ip parent ffff: \
		flower \
		src_mac e4:1d:2d:fd:8b:01 \
		dst_mac e4:1d:2d:fd:8b:02 \
		indev ens4f0 \
		matching_flags 0x1/0x1 \
	action drop

Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>

diff --git a/tc/f_flower.c b/tc/f_flower.c
index 4d305b6e1e6317acb46ccb2bf6a4fd8f723da026..ba8b756b8a9efbf09bc8c33601110e514a4d0ee9 100644 (file)
--- a/tc/f_flower.c
+++ b/tc/f_flower.c
@@ -57,6 +57,7 @@ static void explain(void)
                "                       enc_dst_ip [ IPV4-ADDR | IPV6-ADDR ] |\n"
                "                       enc_src_ip [ IPV4-ADDR | IPV6-ADDR ] |\n"
                "                       enc_key_id [ KEY-ID ] |\n"
+               "                       matching_flags MATCHING-FLAGS | \n"
                "                       enc_dst_port [ UDP-PORT ] }\n"
                "       FILTERID := X:Y:Z\n"
                "       MASKED_LLADDR := { LLADDR | LLADDR/MASK | LLADDR/BITS }\n"
@@ -129,6 +130,31 @@ static int flower_parse_vlan_eth_type(char *str, __be16 eth_type, int type,
        return 0;
 }
 
+static int flower_parse_matching_flags(char *str, int type, int mask_type,
+                                      struct nlmsghdr *n)
+{
+       __u32 mtf, mtf_mask;
+       char *c;
+
+       c = strchr(str, '/');
+       if (c)
+               *c = '\0';
+
+       if (get_u32(&mtf, str, 0))
+               return -1;
+
+       if (c) {
+               if (get_u32(&mtf_mask, ++c, 0))
+                       return -1;
+       } else {
+               mtf_mask = 0xffffffff;
+       }
+
+       addattr32(n, MAX_MSG, type, htonl(mtf));
+       addattr32(n, MAX_MSG, mask_type, htonl(mtf_mask));
+       return 0;
+}
+
 static int flower_parse_ip_proto(char *str, __be16 eth_type, int type,
                                 __u8 *p_ip_proto, struct nlmsghdr *n)
 {
@@ -358,6 +384,16 @@ static int flower_parse_opt(struct filter_util *qu, char *handle,
                                return -1;
                        }
                        addattr_l(n, MAX_MSG, TCA_FLOWER_CLASSID, &handle, 4);
+               } else if (matches(*argv, "matching_flags") == 0) {
+                       NEXT_ARG();
+                       ret = flower_parse_matching_flags(*argv,
+                                                         TCA_FLOWER_KEY_FLAGS,
+                                                         TCA_FLOWER_KEY_FLAGS_MASK,
+                                                         n);
+                       if (ret < 0) {
+                               fprintf(stderr, "Illegal \"matching_flags\"\n");
+                               return -1;
+                       }
                } else if (matches(*argv, "skip_hw") == 0) {
                        flags |= TCA_CLS_FLAGS_SKIP_HW;
                } else if (matches(*argv, "skip_sw") == 0) {
@@ -656,6 +692,17 @@ static void flower_print_ip_proto(FILE *f, __u8 *p_ip_proto,
        *p_ip_proto = ip_proto;
 }
 
+static void flower_print_matching_flags(FILE *f, char *name,
+                                       struct rtattr *attr,
+                                       struct rtattr *mask_attr)
+{
+       if (!mask_attr || RTA_PAYLOAD(mask_attr) != 4)
+               return;
+
+       fprintf(f, "\n  %s 0x%08x/0x%08x", name, ntohl(rta_getattr_u32(attr)),
+               mask_attr ? ntohl(rta_getattr_u32(mask_attr)) : 0xffffffff);
+}
+
 static void flower_print_ip_addr(FILE *f, char *name, __be16 eth_type,
                                 struct rtattr *addr4_attr,
                                 struct rtattr *mask4_attr,
@@ -809,6 +856,10 @@ static int flower_print_opt(struct filter_util *qu, FILE *f,
        flower_print_port(f, "enc_dst_port",
                          tb[TCA_FLOWER_KEY_ENC_UDP_DST_PORT]);
 
+       flower_print_matching_flags(f, "matching_flags",
+                                   tb[TCA_FLOWER_KEY_FLAGS],
+                                   tb[TCA_FLOWER_KEY_FLAGS_MASK]);
+
        if (tb[TCA_FLOWER_FLAGS]) {
                __u32 flags = rta_getattr_u32(tb[TCA_FLOWER_FLAGS]);