From: Jeremy Harris Date: Wed, 23 Apr 2025 12:43:34 +0000 (+0100) Subject: tcp: fastopen: pass TFO child indication through getsockopt X-Git-Tag: v6.16-rc1~132^2~218^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2b13042d3636327eb50c8a0ee06f629d52d1b8fb;p=thirdparty%2Flinux.git 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 Reviewed-by: Eric Dumazet Reviewed-by: Neal Cardwell Link: https://patch.msgid.link/20250423124334.4916-3-jgh@exim.org Signed-off-by: Jakub Kicinski --- diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index dc8fdc80e16b0..bdac8c42fa82a 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 df3eb0fb7cb3d..86c427f166367 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,