Re: [RFC v2 net-next 01/10] net: Add a new socket option for a future transmit time.
From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: 2018-01-19 21:16:27
Also in:
intel-wired-lan
On Wed, Jan 17, 2018 at 6:06 PM, Jesus Sanchez-Palencia [off-list ref] wrote:
From: Richard Cochran <redacted> This patch introduces SO_TXTIME. User space enables this option in order to pass a desired future transmit time in a CMSG when calling sendmsg(2). A new field is added to struct sockcm_cookie, and the tstamp from skbuffs will be used later on. Signed-off-by: Richard Cochran <redacted> Signed-off-by: Jesus Sanchez-Palencia <redacted> ---
quoted hunk ↗ jump to hunk
diff --git a/net/core/sock.c b/net/core/sock.c index abf4cbff99b2..37ef4b33fd92 100644 --- a/net/core/sock.c +++ b/net/core/sock.c@@ -1061,6 +1061,13 @@ int sock_setsockopt(struct socket *sock, int level, int optname, sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); break; + case SO_TXTIME: + if (ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + sock_valbool_flag(sk, SOCK_TXTIME, valbool); + else + ret = -EPERM; + break; + default: ret = -ENOPROTOOPT; break;
Please add getsockopt alongside setsockopt. I would also restrict input to [0, 1] exactly to allow for future extensions. If using ns_capable, skb->tstamp must continue to be scrubbed when traversing network namespaces.
quoted hunk ↗ jump to hunk
@@ -2130,6 +2137,15 @@ int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; sockc->tsflags |= tsflags; break; + case SO_TXTIME: + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + return -EPERM; + if (!sock_flag(sk, SOCK_TXTIME)) + return -EINVAL;
No need for ns_capable check on each packet when already required to toggle socket option.
+ if (cmsg->cmsg_len != CMSG_LEN(sizeof(ktime_t))) + return -EINVAL;
I don't see any existing reference to ktime_t in include/uapi. Just use a s64?