ipv4: support sport, dport and ip_proto in RTM_GETROUTE

This is a followup to fib rules sport, dport and ipproto
match support. Only supports tcp, udp and icmp for ipproto.
Used by fib rule self tests.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/ip.h b/include/net/ip.h
index bada1f1..0d2281b 100644 (file)
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -664,4 +664,7 @@ extern int sysctl_icmp_msgs_burst;
 int ip_misc_proc_init(void);
 #endif
 
+int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto,
+                               struct netlink_ext_ack *extack);
+
 #endif /* _IP_H */

diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index 9b15005..cabb210 100644 (file)
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -327,6 +327,9 @@ enum rtattr_type_t {
        RTA_PAD,
        RTA_UID,
        RTA_TTL_PROPAGATE,
+       RTA_IP_PROTO,
+       RTA_SPORT,
+       RTA_DPORT,
        __RTA_MAX
 };
 

diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 7018f91..eec9569 100644 (file)
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -14,7 +14,7 @@ obj-y     := route.o inetpeer.o protocol.o \
             udp_offload.o arp.o icmp.o devinet.o af_inet.o igmp.o \
             fib_frontend.o fib_semantics.o fib_trie.o fib_notifier.o \
             inet_fragment.o ping.o ip_tunnel_core.o gre_offload.o \
-            metrics.o
+            metrics.o netlink.o
 
 obj-$(CONFIG_BPFILTER) += bpfilter/
 

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 4d62211..897ae92 100644 (file)
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -649,6 +649,9 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
        [RTA_ENCAP]             = { .type = NLA_NESTED },
        [RTA_UID]               = { .type = NLA_U32 },
        [RTA_MARK]              = { .type = NLA_U32 },
+       [RTA_IP_PROTO]          = { .type = NLA_U8 },
+       [RTA_SPORT]             = { .type = NLA_U16 },
+       [RTA_DPORT]             = { .type = NLA_U16 },
 };
 
 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,

diff --git a/net/ipv4/netlink.c b/net/ipv4/netlink.c
new file mode 100644 (file)
index 0000000..f86bb4f
--- /dev/null
+++ b/net/ipv4/netlink.c
@@ -0,0 +1,23 @@
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <linux/types.h>
+#include <net/net_namespace.h>
+#include <net/netlink.h>
+#include <net/ip.h>
+
+int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto,
+                               struct netlink_ext_ack *extack)
+{
+       *ip_proto = nla_get_u8(attr);
+
+       switch (*ip_proto) {
+       case IPPROTO_TCP:
+       case IPPROTO_UDP:
+       case IPPROTO_ICMP:
+               return 0;
+       default:
+               NL_SET_ERR_MSG(extack, "Unsupported ip proto");
+               return -EOPNOTSUPP;
+       }
+}
+EXPORT_SYMBOL_GPL(rtm_getroute_parse_ip_proto);

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 2cfa1b5..0e401dc 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2574,11 +2574,10 @@ struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
 EXPORT_SYMBOL_GPL(ip_route_output_flow);
 
 /* called with rcu_read_lock held */
-static int rt_fill_info(struct net *net,  __be32 dst, __be32 src, u32 table_id,
-                       struct flowi4 *fl4, struct sk_buff *skb, u32 portid,
-                       u32 seq)
+static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
+                       struct rtable *rt, u32 table_id, struct flowi4 *fl4,
+                       struct sk_buff *skb, u32 portid, u32 seq)
 {
-       struct rtable *rt = skb_rtable(skb);
        struct rtmsg *r;
        struct nlmsghdr *nlh;
        unsigned long expires = 0;
@@ -2674,7 +2673,7 @@ static int rt_fill_info(struct net *net,  __be32 dst, __be32 src, u32 table_id,
                        }
                } else
 #endif
-                       if (nla_put_u32(skb, RTA_IIF, skb->dev->ifindex))
+                       if (nla_put_u32(skb, RTA_IIF, fl4->flowi4_iif))
                                goto nla_put_failure;
        }
 
@@ -2689,43 +2688,93 @@ nla_put_failure:
        return -EMSGSIZE;
 }
 
+static struct sk_buff *inet_rtm_getroute_build_skb(__be32 src, __be32 dst,
+                                                  u8 ip_proto, __be16 sport,
+                                                  __be16 dport)
+{
+       struct sk_buff *skb;
+       struct iphdr *iph;
+
+       skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+       if (!skb)
+               return NULL;
+
+       /* Reserve room for dummy headers, this skb can pass
+        * through good chunk of routing engine.
+        */
+       skb_reset_mac_header(skb);
+       skb_reset_network_header(skb);
+       skb->protocol = htons(ETH_P_IP);
+       iph = skb_put(skb, sizeof(struct iphdr));
+       iph->protocol = ip_proto;
+       iph->saddr = src;
+       iph->daddr = dst;
+       iph->version = 0x4;
+       iph->frag_off = 0;
+       iph->ihl = 0x5;
+       skb_set_transport_header(skb, skb->len);
+
+       switch (iph->protocol) {
+       case IPPROTO_UDP: {
+               struct udphdr *udph;
+
+               udph = skb_put_zero(skb, sizeof(struct udphdr));
+               udph->source = sport;
+               udph->dest = dport;
+               udph->len = sizeof(struct udphdr);
+               udph->check = 0;
+               break;
+       }
+       case IPPROTO_TCP: {
+               struct tcphdr *tcph;
+
+               tcph = skb_put_zero(skb, sizeof(struct tcphdr));
+               tcph->source    = sport;
+               tcph->dest      = dport;
+               tcph->doff      = sizeof(struct tcphdr) / 4;
+               tcph->rst = 1;
+               tcph->check = ~tcp_v4_check(sizeof(struct tcphdr),
+                                           src, dst, 0);
+               break;
+       }
+       case IPPROTO_ICMP: {
+               struct icmphdr *icmph;
+
+               icmph = skb_put_zero(skb, sizeof(struct icmphdr));
+               icmph->type = ICMP_ECHO;
+               icmph->code = 0;
+       }
+       }
+
+       return skb;
+}
+
 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
                             struct netlink_ext_ack *extack)
 {
        struct net *net = sock_net(in_skb->sk);
-       struct rtmsg *rtm;
        struct nlattr *tb[RTA_MAX+1];
+       u32 table_id = RT_TABLE_MAIN;
+       __be16 sport = 0, dport = 0;
        struct fib_result res = {};
+       u8 ip_proto = IPPROTO_UDP;
        struct rtable *rt = NULL;
+       struct sk_buff *skb;
+       struct rtmsg *rtm;
        struct flowi4 fl4;
        __be32 dst = 0;
        __be32 src = 0;
+       kuid_t uid;
        u32 iif;
        int err;
        int mark;
-       struct sk_buff *skb;
-       u32 table_id = RT_TABLE_MAIN;
-       kuid_t uid;
 
        err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy,
                          extack);
        if (err < 0)
-               goto errout;
+               return err;
 
        rtm = nlmsg_data(nlh);
-
-       skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
-       if (!skb) {
-               err = -ENOBUFS;
-               goto errout;
-       }
-
-       /* Reserve room for dummy headers, this skb can pass
-          through good chunk of routing engine.
-        */
-       skb_reset_mac_header(skb);
-       skb_reset_network_header(skb);
-
        src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
        dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
        iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
@@ -2735,14 +2784,22 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
        else
                uid = (iif ? INVALID_UID : current_uid());
 
-       /* Bugfix: need to give ip_route_input enough of an IP header to
-        * not gag.
-        */
-       ip_hdr(skb)->protocol = IPPROTO_UDP;
-       ip_hdr(skb)->saddr = src;
-       ip_hdr(skb)->daddr = dst;
+       if (tb[RTA_IP_PROTO]) {
+               err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
+                                                 &ip_proto, extack);
+               if (err)
+                       return err;
+       }
+
+       if (tb[RTA_SPORT])
+               sport = nla_get_be16(tb[RTA_SPORT]);
 
-       skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
+       if (tb[RTA_DPORT])
+               dport = nla_get_be16(tb[RTA_DPORT]);
+
+       skb = inet_rtm_getroute_build_skb(src, dst, ip_proto, sport, dport);
+       if (!skb)
+               return -ENOBUFS;
 
        memset(&fl4, 0, sizeof(fl4));
        fl4.daddr = dst;
@@ -2751,6 +2808,11 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
        fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
        fl4.flowi4_mark = mark;
        fl4.flowi4_uid = uid;
+       if (sport)
+               fl4.fl4_sport = sport;
+       if (dport)
+               fl4.fl4_dport = dport;
+       fl4.flowi4_proto = ip_proto;
 
        rcu_read_lock();
 
@@ -2760,10 +2822,10 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
                dev = dev_get_by_index_rcu(net, iif);
                if (!dev) {
                        err = -ENODEV;
-                       goto errout_free;
+                       goto errout_rcu;
                }
 
-               skb->protocol   = htons(ETH_P_IP);
+               fl4.flowi4_iif = iif; /* for rt_fill_info */
                skb->dev        = dev;
                skb->mark       = mark;
                err = ip_route_input_rcu(skb, dst, src, rtm->rtm_tos,
@@ -2783,7 +2845,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
        }
 
        if (err)
-               goto errout_free;
+               goto errout_rcu;
 
        if (rtm->rtm_flags & RTM_F_NOTIFY)
                rt->rt_flags |= RTCF_NOTIFY;
@@ -2791,34 +2853,40 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
        if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE)
                table_id = res.table ? res.table->tb_id : 0;
 
+       /* reset skb for netlink reply msg */
+       skb_trim(skb, 0);
+       skb_reset_network_header(skb);
+       skb_reset_transport_header(skb);
+       skb_reset_mac_header(skb);
+
        if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
                if (!res.fi) {
                        err = fib_props[res.type].error;
                        if (!err)
                                err = -EHOSTUNREACH;
-                       goto errout_free;
+                       goto errout_rcu;
                }
                err = fib_dump_info(skb, NETLINK_CB(in_skb).portid,
                                    nlh->nlmsg_seq, RTM_NEWROUTE, table_id,
                                    rt->rt_type, res.prefix, res.prefixlen,
                                    fl4.flowi4_tos, res.fi, 0);
        } else {
-               err = rt_fill_info(net, dst, src, table_id, &fl4, skb,
+               err = rt_fill_info(net, dst, src, rt, table_id, &fl4, skb,
                                   NETLINK_CB(in_skb).portid, nlh->nlmsg_seq);
        }
        if (err < 0)
-               goto errout_free;
+               goto errout_rcu;
 
        rcu_read_unlock();
 
        err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
-errout:
-       return err;
 
 errout_free:
+       return err;
+errout_rcu:
        rcu_read_unlock();
        kfree_skb(skb);
-       goto errout;
+       goto errout_free;
 }
 
 void ip_rt_multicast_event(struct in_device *in_dev)