[PATCH iproute2 1/6] ip vrf: Add name_is_vrf

[David Ahern]

Add name_is_vrf function to determine if given name corresponds to a
VRF device.

Signed-off-by: David Ahern <d...@cumulusnetworks.com>
---
 ip/ip_common.h  |  2 ++
 ip/iplink_vrf.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/ip/ip_common.h b/ip/ip_common.h
index e8da9e034b15..410eb135774a 100644
--- a/ip/ip_common.h
+++ b/ip/ip_common.h
@@ -90,6 +90,8 @@ struct link_util *get_link_slave_kind(const char *slave_kind);
 
 void br_dump_bridge_id(const struct ifla_bridge_id *id, char *buf, size_t len);
 
+bool name_is_vrf(char *name);
+
 #ifndef        INFINITY_LIFE_TIME
 #define     INFINITY_LIFE_TIME      0xFFFFFFFFU
 #endif
diff --git a/ip/iplink_vrf.c b/ip/iplink_vrf.c
index e3c7b4652da5..abd43c08423e 100644
--- a/ip/iplink_vrf.c
+++ b/ip/iplink_vrf.c
@@ -96,3 +96,56 @@ struct link_util vrf_slave_link_util = {
        .print_opt      = vrf_slave_print_opt,
        .slave          = true,
 };
+
+bool name_is_vrf(char *name)
+{
+       struct {
+               struct nlmsghdr         n;
+               struct ifinfomsg        i;
+               char                    buf[1024];
+       } req = {
+               .n = {
+                       .nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
+                       .nlmsg_flags = NLM_F_REQUEST,
+                       .nlmsg_type  = RTM_GETLINK,
+               },
+               .i = {
+                       .ifi_family  = preferred_family,
+               },
+       };
+       struct {
+               struct nlmsghdr n;
+               char buf[8192];
+       } answer;
+       struct rtattr *tb[IFLA_MAX+1];
+       struct rtattr *li[IFLA_INFO_MAX+1];
+       struct ifinfomsg *ifi;
+       int len;
+
+       addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, strlen(name) + 1);
+
+       if (rtnl_talk(&rth, &req.n, &answer.n, sizeof(answer)) < 0)
+               goto err;
+
+       ifi = NLMSG_DATA(&answer.n);
+       len = answer.n.nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
+       if (len < 0) {
+               fprintf(stderr, "BUG: Invalid response to link query.\n");
+               goto err;
+       }
+
+       parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
+
+       if (!tb[IFLA_LINKINFO])
+               goto err;
+
+       parse_rtattr_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
+
+       if (!li[IFLA_INFO_KIND])
+               goto err;
+
+       return strcmp(RTA_DATA(li[IFLA_INFO_KIND]), "vrf") == 0;
+
+err:
+       return false;
+}
-- 
2.1.4