net: ipmr: remove some pimsm ifdefs and simplify

Add the helper pimsm_enabled() which replaces the old CONFIG_IP_PIMSM
define and is used to check if any version of PIM-SM has been enabled.
Use a single if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
for the pim-sm shared code. This is okay w.r.t IGMPMSG_WHOLEPKT because
only a VIFF_REGISTER device can send such packet, and it can't be
created if pimsm_enabled() is false.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index dd2462f70d3432621d9f278ce02d9299a8ce6f67..e153ab7b17a143a3869bc5aa7091ff478bb31435 100644 (file)
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -67,10 +67,6 @@
 #include <net/fib_rules.h>
 #include <linux/netconf.h>
 
-#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
-#define CONFIG_IP_PIMSM        1
-#endif
-
 struct mr_table {
        struct list_head        list;
        possible_net_t          net;
@@ -95,6 +91,11 @@ struct ipmr_result {
        struct mr_table         *mrt;
 };
 
+static inline bool pimsm_enabled(void)
+{
+       return IS_BUILTIN(CONFIG_IP_PIMSM_V1) || IS_BUILTIN(CONFIG_IP_PIMSM_V2);
+}
+
 /* Big lock, protecting vif table, mrt cache and mroute socket state.
  * Note that the changes are semaphored via rtnl_lock.
  */
@@ -454,8 +455,7 @@ failure:
        return NULL;
 }
 
-#ifdef CONFIG_IP_PIMSM
-
+#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
 static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
 {
        struct net *net = dev_net(dev);
@@ -552,6 +552,51 @@ failure:
        unregister_netdevice(dev);
        return NULL;
 }
+
+/* called with rcu_read_lock() */
+static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
+                    unsigned int pimlen)
+{
+       struct net_device *reg_dev = NULL;
+       struct iphdr *encap;
+
+       encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
+       /*
+        * Check that:
+        * a. packet is really sent to a multicast group
+        * b. packet is not a NULL-REGISTER
+        * c. packet is not truncated
+        */
+       if (!ipv4_is_multicast(encap->daddr) ||
+           encap->tot_len == 0 ||
+           ntohs(encap->tot_len) + pimlen > skb->len)
+               return 1;
+
+       read_lock(&mrt_lock);
+       if (mrt->mroute_reg_vif_num >= 0)
+               reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
+       read_unlock(&mrt_lock);
+
+       if (!reg_dev)
+               return 1;
+
+       skb->mac_header = skb->network_header;
+       skb_pull(skb, (u8 *)encap - skb->data);
+       skb_reset_network_header(skb);
+       skb->protocol = htons(ETH_P_IP);
+       skb->ip_summed = CHECKSUM_NONE;
+
+       skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
+
+       netif_rx(skb);
+
+       return NET_RX_SUCCESS;
+}
+#else
+static struct net_device *ipmr_reg_vif(struct net *net, struct mr_table *mrt)
+{
+       return NULL;
+}
 #endif
 
 /**
@@ -734,10 +779,10 @@ static int vif_add(struct net *net, struct mr_table *mrt,
                return -EADDRINUSE;
 
        switch (vifc->vifc_flags) {
-#ifdef CONFIG_IP_PIMSM
        case VIFF_REGISTER:
-               /*
-                * Special Purpose VIF in PIM
+               if (!pimsm_enabled())
+                       return -EINVAL;
+               /* Special Purpose VIF in PIM
                 * All the packets will be sent to the daemon
                 */
                if (mrt->mroute_reg_vif_num >= 0)
@@ -752,7 +797,6 @@ static int vif_add(struct net *net, struct mr_table *mrt,
                        return err;
                }
                break;
-#endif
        case VIFF_TUNNEL:
                dev = ipmr_new_tunnel(net, vifc);
                if (!dev)
@@ -942,34 +986,29 @@ static void ipmr_cache_resolve(struct net *net, struct mr_table *mrt,
        }
 }
 
-/*
- *     Bounce a cache query up to mrouted. We could use netlink for this but mrouted
- *     expects the following bizarre scheme.
+/* Bounce a cache query up to mrouted. We could use netlink for this but mrouted
+ * expects the following bizarre scheme.
  *
- *     Called under mrt_lock.
+ * Called under mrt_lock.
  */
-
 static int ipmr_cache_report(struct mr_table *mrt,
                             struct sk_buff *pkt, vifi_t vifi, int assert)
 {
-       struct sk_buff *skb;
        const int ihl = ip_hdrlen(pkt);
+       struct sock *mroute_sk;
        struct igmphdr *igmp;
        struct igmpmsg *msg;
-       struct sock *mroute_sk;
+       struct sk_buff *skb;
        int ret;
 
-#ifdef CONFIG_IP_PIMSM
        if (assert == IGMPMSG_WHOLEPKT)
                skb = skb_realloc_headroom(pkt, sizeof(struct iphdr));
        else
-#endif
                skb = alloc_skb(128, GFP_ATOMIC);
 
        if (!skb)
                return -ENOBUFS;
 
-#ifdef CONFIG_IP_PIMSM
        if (assert == IGMPMSG_WHOLEPKT) {
                /* Ugly, but we have no choice with this interface.
                 * Duplicate old header, fix ihl, length etc.
@@ -987,28 +1026,23 @@ static int ipmr_cache_report(struct mr_table *mrt,
                ip_hdr(skb)->ihl = sizeof(struct iphdr) >> 2;
                ip_hdr(skb)->tot_len = htons(ntohs(ip_hdr(pkt)->tot_len) +
                                             sizeof(struct iphdr));
-       } else
-#endif
-       {
-
-       /* Copy the IP header */
-
-       skb_set_network_header(skb, skb->len);
-       skb_put(skb, ihl);
-       skb_copy_to_linear_data(skb, pkt->data, ihl);
-       ip_hdr(skb)->protocol = 0;      /* Flag to the kernel this is a route add */
-       msg = (struct igmpmsg *)skb_network_header(skb);
-       msg->im_vif = vifi;
-       skb_dst_set(skb, dst_clone(skb_dst(pkt)));
-
-       /* Add our header */
-
-       igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
-       igmp->type      =
-       msg->im_msgtype = assert;
-       igmp->code      = 0;
-       ip_hdr(skb)->tot_len = htons(skb->len);         /* Fix the length */
-       skb->transport_header = skb->network_header;
+       } else {
+               /* Copy the IP header */
+               skb_set_network_header(skb, skb->len);
+               skb_put(skb, ihl);
+               skb_copy_to_linear_data(skb, pkt->data, ihl);
+               /* Flag to the kernel this is a route add */
+               ip_hdr(skb)->protocol = 0;
+               msg = (struct igmpmsg *)skb_network_header(skb);
+               msg->im_vif = vifi;
+               skb_dst_set(skb, dst_clone(skb_dst(pkt)));
+               /* Add our header */
+               igmp = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
+               igmp->type = assert;
+               msg->im_msgtype = assert;
+               igmp->code = 0;
+               ip_hdr(skb)->tot_len = htons(skb->len); /* Fix the length */
+               skb->transport_header = skb->network_header;
        }
 
        rcu_read_lock();
@@ -1020,7 +1054,6 @@ static int ipmr_cache_report(struct mr_table *mrt,
        }
 
        /* Deliver to mrouted */
-
        ret = sock_queue_rcv_skb(mroute_sk, skb);
        rcu_read_unlock();
        if (ret < 0) {
@@ -1377,11 +1410,12 @@ int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsi
                mrt->mroute_do_assert = v;
                return 0;
        }
-#ifdef CONFIG_IP_PIMSM
        case MRT_PIM:
        {
                int v;
 
+               if (!pimsm_enabled())
+                       return -ENOPROTOOPT;
                if (optlen != sizeof(v))
                        return -EINVAL;
                if (get_user(v, (int __user *)optval))
@@ -1397,7 +1431,6 @@ int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsi
                rtnl_unlock();
                return ret;
        }
-#endif
 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
        case MRT_TABLE:
        {
@@ -1452,9 +1485,7 @@ int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int
                return -ENOENT;
 
        if (optname != MRT_VERSION &&
-#ifdef CONFIG_IP_PIMSM
           optname != MRT_PIM &&
-#endif
           optname != MRT_ASSERT)
                return -ENOPROTOOPT;
 
@@ -1467,14 +1498,15 @@ int ip_mroute_getsockopt(struct sock *sk, int optname, char __user *optval, int
 
        if (put_user(olr, optlen))
                return -EFAULT;
-       if (optname == MRT_VERSION)
+       if (optname == MRT_VERSION) {
                val = 0x0305;
-#ifdef CONFIG_IP_PIMSM
-       else if (optname == MRT_PIM)
+       } else if (optname == MRT_PIM) {
+               if (!pimsm_enabled())
+                       return -ENOPROTOOPT;
                val = mrt->mroute_do_pim;
-#endif
-       else
+       } else {
                val = mrt->mroute_do_assert;
+       }
        if (copy_to_user(optval, &val, olr))
                return -EFAULT;
        return 0;
@@ -1707,7 +1739,6 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
        if (!vif->dev)
                goto out_free;
 
-#ifdef CONFIG_IP_PIMSM
        if (vif->flags & VIFF_REGISTER) {
                vif->pkt_out++;
                vif->bytes_out += skb->len;
@@ -1716,7 +1747,6 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
                ipmr_cache_report(mrt, skb, vifi, IGMPMSG_WHOLEPKT);
                goto out_free;
        }
-#endif
 
        if (vif->flags & VIFF_TUNNEL) {
                rt = ip_route_output_ports(net, &fl4, NULL,
@@ -2047,48 +2077,6 @@ dont_forward:
        return 0;
 }
 
-#ifdef CONFIG_IP_PIMSM
-/* called with rcu_read_lock() */
-static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb,
-                    unsigned int pimlen)
-{
-       struct net_device *reg_dev = NULL;
-       struct iphdr *encap;
-
-       encap = (struct iphdr *)(skb_transport_header(skb) + pimlen);
-       /*
-        * Check that:
-        * a. packet is really sent to a multicast group
-        * b. packet is not a NULL-REGISTER
-        * c. packet is not truncated
-        */
-       if (!ipv4_is_multicast(encap->daddr) ||
-           encap->tot_len == 0 ||
-           ntohs(encap->tot_len) + pimlen > skb->len)
-               return 1;
-
-       read_lock(&mrt_lock);
-       if (mrt->mroute_reg_vif_num >= 0)
-               reg_dev = mrt->vif_table[mrt->mroute_reg_vif_num].dev;
-       read_unlock(&mrt_lock);
-
-       if (!reg_dev)
-               return 1;
-
-       skb->mac_header = skb->network_header;
-       skb_pull(skb, (u8 *)encap - skb->data);
-       skb_reset_network_header(skb);
-       skb->protocol = htons(ETH_P_IP);
-       skb->ip_summed = CHECKSUM_NONE;
-
-       skb_tunnel_rx(skb, reg_dev, dev_net(reg_dev));
-
-       netif_rx(skb);
-
-       return NET_RX_SUCCESS;
-}
-#endif
-
 #ifdef CONFIG_IP_PIMSM_V1
 /*
  * Handle IGMP messages of PIMv1