[PATCH 10/19] ipv4: take handling of group_source_req options into a helper

From: Al Viro
Date: Mon May 11 2020 - 00:46:59 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
net/ipv4/ip_sockglue.c | 83 ++++++++++++++++++++++++++------------------------
1 file changed, 44 insertions(+), 39 deletions(-)

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 937f39906419..4f412b0bdda4 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -624,6 +624,49 @@ static int set_mcast_msfilter(struct sock *sk, int ifindex,
return -EADDRNOTAVAIL;
}

+static int do_mcast_group_source(struct sock *sk, int optname,
+ struct group_source_req *greqs)
+{
+ struct ip_mreq_source mreqs;
+ struct sockaddr_in *psin;
+ int omode, add, err;
+
+ if (greqs->gsr_group.ss_family != AF_INET ||
+ greqs->gsr_source.ss_family != AF_INET)
+ return -EADDRNOTAVAIL;
+
+ psin = (struct sockaddr_in *)&greqs->gsr_group;
+ mreqs.imr_multiaddr = psin->sin_addr.s_addr;
+ psin = (struct sockaddr_in *)&greqs->gsr_source;
+ mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
+ mreqs.imr_interface = 0; /* use index for mc_source */
+
+ if (optname == MCAST_BLOCK_SOURCE) {
+ omode = MCAST_EXCLUDE;
+ add = 1;
+ } else if (optname == MCAST_UNBLOCK_SOURCE) {
+ omode = MCAST_EXCLUDE;
+ add = 0;
+ } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
+ struct ip_mreqn mreq;
+
+ psin = (struct sockaddr_in *)&greqs->gsr_group;
+ mreq.imr_multiaddr = psin->sin_addr;
+ mreq.imr_address.s_addr = 0;
+ mreq.imr_ifindex = greqs->gsr_interface;
+ err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
+ if (err && err != -EADDRINUSE)
+ return err;
+ greqs->gsr_interface = mreq.imr_ifindex;
+ omode = MCAST_INCLUDE;
+ add = 1;
+ } else /* MCAST_LEAVE_SOURCE_GROUP */ {
+ omode = MCAST_INCLUDE;
+ add = 0;
+ }
+ return ip_mc_source(add, omode, sk, &mreqs, greqs->gsr_interface);
+}
+
static int do_ip_setsockopt(struct sock *sk, int level,
int optname, char __user *optval, unsigned int optlen)
{
@@ -1066,9 +1109,6 @@ static int do_ip_setsockopt(struct sock *sk, int level,
case MCAST_UNBLOCK_SOURCE:
{
struct group_source_req greqs;
- struct ip_mreq_source mreqs;
- struct sockaddr_in *psin;
- int omode, add;

if (optlen != sizeof(struct group_source_req))
goto e_inval;
@@ -1076,42 +1116,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
err = -EFAULT;
break;
}
- if (greqs.gsr_group.ss_family != AF_INET ||
- greqs.gsr_source.ss_family != AF_INET) {
- err = -EADDRNOTAVAIL;
- break;
- }
- psin = (struct sockaddr_in *)&greqs.gsr_group;
- mreqs.imr_multiaddr = psin->sin_addr.s_addr;
- psin = (struct sockaddr_in *)&greqs.gsr_source;
- mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
- mreqs.imr_interface = 0; /* use index for mc_source */
-
- if (optname == MCAST_BLOCK_SOURCE) {
- omode = MCAST_EXCLUDE;
- add = 1;
- } else if (optname == MCAST_UNBLOCK_SOURCE) {
- omode = MCAST_EXCLUDE;
- add = 0;
- } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
- struct ip_mreqn mreq;
-
- psin = (struct sockaddr_in *)&greqs.gsr_group;
- mreq.imr_multiaddr = psin->sin_addr;
- mreq.imr_address.s_addr = 0;
- mreq.imr_ifindex = greqs.gsr_interface;
- err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
- if (err && err != -EADDRINUSE)
- break;
- greqs.gsr_interface = mreq.imr_ifindex;
- omode = MCAST_INCLUDE;
- add = 1;
- } else /* MCAST_LEAVE_SOURCE_GROUP */ {
- omode = MCAST_INCLUDE;
- add = 0;
- }
- err = ip_mc_source(add, omode, sk, &mreqs,
- greqs.gsr_interface);
+ err = do_mcast_group_source(sk, optname, &greqs);
break;
}
case MCAST_MSFILTER:
--
2.11.0