summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJeremy Harris <jgh@exim.org>2025-04-23 13:43:34 +0100
committerJakub Kicinski <kuba@kernel.org>2025-04-24 18:21:04 -0700
commit2b13042d3636327eb50c8a0ee06f629d52d1b8fb (patch)
tree56b3c3d26b4e65bbe2ab42f02a6b71c632818cbb
parentbc2550b4e195754fbb24aac1f012d3dd9e3b4edc (diff)
tcp: fastopen: pass TFO child indication through getsockopt
tcp: fastopen: pass TFO child indication through getsockopt Note that this uses up the last bit of a field in struct tcp_info Signed-off-by: Jeremy Harris <jgh@exim.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20250423124334.4916-3-jgh@exim.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-rw-r--r--include/uapi/linux/tcp.h1
-rw-r--r--net/ipv4/tcp.c2
2 files changed, 3 insertions, 0 deletions
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index dc8fdc80e16b..bdac8c42fa82 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -184,6 +184,7 @@ enum tcp_fastopen_client_fail {
#define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */
#define TCPI_OPT_SYN_DATA 32 /* SYN-ACK acked data in SYN sent or rcvd */
#define TCPI_OPT_USEC_TS 64 /* usec timestamps */
+#define TCPI_OPT_TFO_CHILD 128 /* child from a Fast Open option on SYN */
/*
* Sender's congestion state indicating normal or abnormal situations
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index df3eb0fb7cb3..86c427f16636 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4165,6 +4165,8 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
info->tcpi_options |= TCPI_OPT_SYN_DATA;
if (tp->tcp_usec_ts)
info->tcpi_options |= TCPI_OPT_USEC_TS;
+ if (tp->syn_fastopen_child)
+ info->tcpi_options |= TCPI_OPT_TFO_CHILD;
info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto);
info->tcpi_ato = jiffies_to_usecs(min_t(u32, icsk->icsk_ack.ato,