Support setting IPV6_HOPLIMIT, IPV6_TCLASS, IPV6_DONTFRAG
during sendmsg via SOL_IPV6 cmsgs.
tclass and dontfrag are init'ed from struct ipv6_pinfo in
ipcm6_init_sk(), while hlimit is inited to -1, so we need
to handle it being populated via cmsg explicitly.
Leave extension headers and flowlabel unimplemented.
Those are slightly more laborious to test and users
seem to primarily care about IPV6_TCLASS.
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
---
net/ipv6/ip6_output.c | 1 +
net/ipv6/ping.c | 21 ++++++++++++++++-----
2 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 0c6c971ce0a5..3286b64ec03d 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1487,6 +1487,7 @@ static int __ip6_append_data(struct sock *sk,
if (cork->length + length > mtu - headersize && ipc6->dontfrag &&
(sk->sk_protocol == IPPROTO_UDP ||
+ sk->sk_protocol == IPPROTO_ICMPV6 ||
sk->sk_protocol == IPPROTO_RAW)) {
ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
sizeof(struct ipv6hdr));
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index d5544cf67ffe..ff033d16549e 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -101,11 +101,21 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
ipc6.sockc.tsflags = sk->sk_tsflags;
ipc6.sockc.mark = sk->sk_mark;
- err = sock_cmsg_send(sk, msg, &ipc6.sockc);
- if (err)
- return err;
+ if (msg->msg_controllen) {
+ struct ipv6_txoptions opt = {};
+
+ opt.tot_len = sizeof(opt);
+ ipc6.opt = &opt;
- /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
+ err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6);
+ if (err < 0)
+ return err;
+
+ /* Changes to txoptions and flow info are not implemented, yet.
+ * Drop the options, fl6 is wiped below.
+ */
+ ipc6.opt = NULL;
+ }
memset(&fl6, 0, sizeof(fl6));
@@ -140,7 +150,8 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
pfh.wcheck = 0;
pfh.family = AF_INET6;
- ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
+ if (ipc6.hlimit < 0)
+ ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
lock_sock(sk);
err = ip6_append_data(sk, ping_getfrag, &pfh, len,
--
2.34.1
