tcp: Remove TCPCT
TCPCT uses option-number 253, reserved for experimental use and should
not be used in production environments.
Further, TCPCT does not fully implement RFC 6013.
As a nice side-effect, removing TCPCT increases TCP's performance for
very short flows:
Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests
for files of 1KB size.
before this patch:
average (among 7 runs) of 20845.5 Requests/Second
after:
average (among 7 runs) of 21403.6 Requests/Second
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 763c108..ed6a745 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -90,9 +90,6 @@
sack_ok : 4, /* SACK seen on SYN packet */
snd_wscale : 4, /* Window scaling received from sender */
rcv_wscale : 4; /* Window scaling to send to receiver */
- u8 cookie_plus:6, /* bytes in authenticator/cookie option */
- cookie_out_never:1,
- cookie_in_always:1;
u8 num_sacks; /* Number of SACK blocks */
u16 user_mss; /* mss requested by user in ioctl */
u16 mss_clamp; /* Maximal mss, negotiated at connection setup */
@@ -102,7 +99,6 @@
{
rx_opt->tstamp_ok = rx_opt->sack_ok = 0;
rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
- rx_opt->cookie_plus = 0;
}
/* This is the max number of SACKS that we'll generate and process. It's safe
@@ -320,12 +316,6 @@
struct tcp_md5sig_info __rcu *md5sig_info;
#endif
- /* When the cookie options are generated and exchanged, then this
- * object holds a reference to them (cookie_values->kref). Also
- * contains related tcp_cookie_transactions fields.
- */
- struct tcp_cookie_values *cookie_values;
-
/* TCP fastopen related information */
struct tcp_fastopen_request *fastopen_req;
/* fastopen_rsk points to request_sock that resulted in this big
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index a51dbd1..9069e65 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -27,19 +27,13 @@
struct dst_entry;
struct proto;
-/* empty to "strongly type" an otherwise void parameter.
- */
-struct request_values {
-};
-
struct request_sock_ops {
int family;
int obj_size;
struct kmem_cache *slab;
char *slab_name;
int (*rtx_syn_ack)(struct sock *sk,
- struct request_sock *req,
- struct request_values *rvp);
+ struct request_sock *req);
void (*send_ack)(struct sock *sk, struct sk_buff *skb,
struct request_sock *req);
void (*send_reset)(struct sock *sk,
diff --git a/include/net/tcp.h b/include/net/tcp.h
index ab9f947..7f2f171 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -179,7 +179,6 @@
#define TCPOPT_SACK 5 /* SACK Block */
#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
#define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */
-#define TCPOPT_COOKIE 253 /* Cookie extension (experimental) */
#define TCPOPT_EXP 254 /* Experimental */
/* Magic number to be after the option value for sharing TCP
* experimental options. See draft-ietf-tcpm-experimental-options-00.txt
@@ -454,7 +453,7 @@
extern int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t len, int nonblock, int flags, int *addr_len);
extern void tcp_parse_options(const struct sk_buff *skb,
- struct tcp_options_received *opt_rx, const u8 **hvpp,
+ struct tcp_options_received *opt_rx,
int estab, struct tcp_fastopen_cookie *foc);
extern const u8 *tcp_parse_md5sig_option(const struct tcphdr *th);
@@ -476,7 +475,6 @@
extern int tcp_connect(struct sock *sk);
extern struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
struct request_sock *req,
- struct request_values *rvp,
struct tcp_fastopen_cookie *foc);
extern int tcp_disconnect(struct sock *sk, int flags);
@@ -1589,91 +1587,6 @@
#endif
};
-/* Using SHA1 for now, define some constants.
- */
-#define COOKIE_DIGEST_WORDS (SHA_DIGEST_WORDS)
-#define COOKIE_MESSAGE_WORDS (SHA_MESSAGE_BYTES / 4)
-#define COOKIE_WORKSPACE_WORDS (COOKIE_DIGEST_WORDS + COOKIE_MESSAGE_WORDS)
-
-extern int tcp_cookie_generator(u32 *bakery);
-
-/**
- * struct tcp_cookie_values - each socket needs extra space for the
- * cookies, together with (optional) space for any SYN data.
- *
- * A tcp_sock contains a pointer to the current value, and this is
- * cloned to the tcp_timewait_sock.
- *
- * @cookie_pair: variable data from the option exchange.
- *
- * @cookie_desired: user specified tcpct_cookie_desired. Zero
- * indicates default (sysctl_tcp_cookie_size).
- * After cookie sent, remembers size of cookie.
- * Range 0, TCP_COOKIE_MIN to TCP_COOKIE_MAX.
- *
- * @s_data_desired: user specified tcpct_s_data_desired. When the
- * constant payload is specified (@s_data_constant),
- * holds its length instead.
- * Range 0 to TCP_MSS_DESIRED.
- *
- * @s_data_payload: constant data that is to be included in the
- * payload of SYN or SYNACK segments when the
- * cookie option is present.
- */
-struct tcp_cookie_values {
- struct kref kref;
- u8 cookie_pair[TCP_COOKIE_PAIR_SIZE];
- u8 cookie_pair_size;
- u8 cookie_desired;
- u16 s_data_desired:11,
- s_data_constant:1,
- s_data_in:1,
- s_data_out:1,
- s_data_unused:2;
- u8 s_data_payload[0];
-};
-
-static inline void tcp_cookie_values_release(struct kref *kref)
-{
- kfree(container_of(kref, struct tcp_cookie_values, kref));
-}
-
-/* The length of constant payload data. Note that s_data_desired is
- * overloaded, depending on s_data_constant: either the length of constant
- * data (returned here) or the limit on variable data.
- */
-static inline int tcp_s_data_size(const struct tcp_sock *tp)
-{
- return (tp->cookie_values != NULL && tp->cookie_values->s_data_constant)
- ? tp->cookie_values->s_data_desired
- : 0;
-}
-
-/**
- * struct tcp_extend_values - tcp_ipv?.c to tcp_output.c workspace.
- *
- * As tcp_request_sock has already been extended in other places, the
- * only remaining method is to pass stack values along as function
- * parameters. These parameters are not needed after sending SYNACK.
- *
- * @cookie_bakery: cryptographic secret and message workspace.
- *
- * @cookie_plus: bytes in authenticator/cookie option, copied from
- * struct tcp_options_received (above).
- */
-struct tcp_extend_values {
- struct request_values rv;
- u32 cookie_bakery[COOKIE_WORKSPACE_WORDS];
- u8 cookie_plus:6,
- cookie_out_never:1,
- cookie_in_always:1;
-};
-
-static inline struct tcp_extend_values *tcp_xv(struct request_values *rvp)
-{
- return (struct tcp_extend_values *)rvp;
-}
-
extern void tcp_v4_init(void);
extern void tcp_init(void);
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index 6b1ead0..8d776eb 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -102,7 +102,6 @@
#define TCP_QUICKACK 12 /* Block/reenable quick acks */
#define TCP_CONGESTION 13 /* Congestion control algorithm */
#define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */
-#define TCP_COOKIE_TRANSACTIONS 15 /* TCP Cookie Transactions */
#define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/
#define TCP_THIN_DUPACK 17 /* Fast retrans. after 1 dupack */
#define TCP_USER_TIMEOUT 18 /* How long for loss retry before timeout */
@@ -199,29 +198,4 @@
__u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */
};
-/* for TCP_COOKIE_TRANSACTIONS (TCPCT) socket option */
-#define TCP_COOKIE_MIN 8 /* 64-bits */
-#define TCP_COOKIE_MAX 16 /* 128-bits */
-#define TCP_COOKIE_PAIR_SIZE (2*TCP_COOKIE_MAX)
-
-/* Flags for both getsockopt and setsockopt */
-#define TCP_COOKIE_IN_ALWAYS (1 << 0) /* Discard SYN without cookie */
-#define TCP_COOKIE_OUT_NEVER (1 << 1) /* Prohibit outgoing cookies,
- * supercedes everything. */
-
-/* Flags for getsockopt */
-#define TCP_S_DATA_IN (1 << 2) /* Was data received? */
-#define TCP_S_DATA_OUT (1 << 3) /* Was data sent? */
-
-/* TCP_COOKIE_TRANSACTIONS data */
-struct tcp_cookie_transactions {
- __u16 tcpct_flags; /* see above */
- __u8 __tcpct_pad1; /* zero */
- __u8 tcpct_cookie_desired; /* bytes */
- __u16 tcpct_s_data_desired; /* bytes of variable data */
- __u16 tcpct_used; /* bytes in value */
- __u8 tcpct_value[TCP_MSS_DEFAULT];
-};
-
-
#endif /* _UAPI_LINUX_TCP_H */