[PATCHv4 5/7] Allow disabling TCP timestamp options per route
From: Gilad Ben-Yossef <hidden>
Date: 2009-10-28 14:15:34
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
Implement querying and acting upon the no timestamp bit in the feature field. Signed-off-by: Gilad Ben-Yossef <redacted> Sigend-off-by: Ori Finkelman [off-list ref] Sigend-off-by: Yony Amit [off-list ref] --- include/linux/rtnetlink.h | 2 +- net/ipv4/tcp_input.c | 3 ++- net/ipv4/tcp_output.c | 8 ++++++-- 3 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index 9c802a6..2ab8c75 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h@@ -378,7 +378,7 @@ enum #define RTAX_FEATURE_ECN 0x00000001 #define RTAX_FEATURE_NO_SACK 0x00000002 -#define RTAX_FEATURE_TIMESTAMP 0x00000004 +#define RTAX_FEATURE_NO_TSTAMP 0x00000004 #define RTAX_FEATURE_ALLFRAG 0x00000008 struct rta_session
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index b14f780..d2f9742 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c@@ -3755,7 +3755,8 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx, case TCPOPT_TIMESTAMP: if ((opsize == TCPOLEN_TIMESTAMP) && ((estab && opt_rx->tstamp_ok) || - (!estab && sysctl_tcp_timestamps))) { + (!estab && sysctl_tcp_timestamps && + !dst_feature(dst, RTAX_FEATURE_NO_TSTAMP)))) { opt_rx->saw_tstamp = 1; opt_rx->rcv_tsval = get_unaligned_be32(ptr); opt_rx->rcv_tsecr = get_unaligned_be32(ptr + 4);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 64db8dd..8f30c18 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c@@ -488,7 +488,9 @@ static unsigned tcp_syn_options(struct sock *sk, struct sk_buff *skb, opts->mss = tcp_advertise_mss(sk); size += TCPOLEN_MSS_ALIGNED; - if (likely(sysctl_tcp_timestamps && *md5 == NULL)) { + if (likely(sysctl_tcp_timestamps && + !dst_feature(dst, RTAX_FEATURE_NO_TSTAMP) && + *md5 == NULL)) { opts->options |= OPTION_TS; opts->tsval = TCP_SKB_CB(skb)->when; opts->tsecr = tp->rx_opt.ts_recent;
@@ -2317,7 +2319,9 @@ static void tcp_connect_init(struct sock *sk) * See tcp_input.c:tcp_rcv_state_process case TCP_SYN_SENT. */ tp->tcp_header_len = sizeof(struct tcphdr) + - (sysctl_tcp_timestamps ? TCPOLEN_TSTAMP_ALIGNED : 0); + (sysctl_tcp_timestamps && + (!dst_feature(dst, RTAX_FEATURE_NO_TSTAMP) ? + TCPOLEN_TSTAMP_ALIGNED : 0)); #ifdef CONFIG_TCP_MD5SIG if (tp->af_specific->md5_lookup(sk, sk) != NULL)
--
1.5.6.3