diff options
| author |   Eric Dumazet <edumazet@google.com> | 2016-09-07 21:52:56 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2016-09-08 17:45:57 -0700 |
| commit | e895cdce683161081e3626c4f5a5c55cb72089f8 (patch) | |
| tree | 59fb73c7597f6a72969991254145dc5ca1a4817d | |
| parent | bpf: fix range propagation on direct packet access (diff) | |
| download | linux-dev-e895cdce683161081e3626c4f5a5c55cb72089f8.tar.xz linux-dev-e895cdce683161081e3626c4f5a5c55cb72089f8.zip | |
ipv4: accept u8 in IP_TOS ancillary data
In commit f02db315b8d8 ("ipv4: IP_TOS and IP_TTL can be specified as
ancillary data") Francesco added IP_TOS values specified as integer.
However, kernel sends to userspace (at recvmsg() time) an IP_TOS value
in a single byte, when IP_RECVTOS is set on the socket.
It can be very useful to reflect all ancillary options as given by the
kernel in a subsequent sendmsg(), instead of aborting the sendmsg() with
EINVAL after Francesco patch.
So this patch extends IP_TOS ancillary to accept an u8, so that an UDP
server can simply reuse same ancillary block without having to mangle
it.
Jesper can then augment
https://github.com/netoptimizer/network-testing/blob/master/src/udp_example02.c
to add TOS reflection ;)
Fixes: f02db315b8d8 ("ipv4: IP_TOS and IP_TTL can be specified as ancillary data")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/ip_sockglue.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 71a52f4d4cff..af4919792b6a 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -284,9 +284,12 @@ int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc, ipc->ttl = val; break; case IP_TOS: - if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) + if (cmsg->cmsg_len == CMSG_LEN(sizeof(int))) + val = *(int *)CMSG_DATA(cmsg); + else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8))) + val = *(u8 *)CMSG_DATA(cmsg); + else return -EINVAL; - val = *(int *)CMSG_DATA(cmsg); if (val < 0 || val > 255) return -EINVAL; ipc->tos = val; |