TCPCT part 1c: sysctl_tcp_cookie_size, socket option TCP_COOKIE_TRANSACTIONS
Define sysctl (tcp_cookie_size) to turn on and off the cookie option default globally, instead of a compiled configuration option. Define per socket option (TCP_COOKIE_TRANSACTIONS) for setting constant data values, retrieving variable cookie values, and other facilities. Move inline tcp_clear_options() unchanged from net/tcp.h to linux/tcp.h, near its corresponding struct tcp_options_received (prior to changes). This is a straightforward re-implementation of an earlier (year-old) patch that no longer applies cleanly, with permission of the original author (Adam Langley): http://thread.gmane.org/gmane.linux.network/102586 These functions will also be used in subsequent patches that implement additional features. Requires: net: TCP_MSS_DEFAULT, TCP_MSS_DESIRED Signed-off-by: William.Allen.Simpson@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
da5c78c826
commit
519855c508
|
@ -164,6 +164,14 @@ tcp_congestion_control - STRING
|
|||
additional choices may be available based on kernel configuration.
|
||||
Default is set as part of kernel configuration.
|
||||
|
||||
tcp_cookie_size - INTEGER
|
||||
Default size of TCP Cookie Transactions (TCPCT) option, that may be
|
||||
overridden on a per socket basis by the TCPCT socket option.
|
||||
Values greater than the maximum (16) are interpreted as the maximum.
|
||||
Values greater than zero and less than the minimum (8) are interpreted
|
||||
as the minimum. Odd values are interpreted as the next even value.
|
||||
Default: 0 (off).
|
||||
|
||||
tcp_dsack - BOOLEAN
|
||||
Allows TCP to send "duplicate" SACKs.
|
||||
|
||||
|
|
|
@ -102,7 +102,9 @@ enum {
|
|||
#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 */
|
||||
|
||||
/* for TCP_INFO socket option */
|
||||
#define TCPI_OPT_TIMESTAMPS 1
|
||||
#define TCPI_OPT_SACK 2
|
||||
#define TCPI_OPT_WSCALE 4
|
||||
|
@ -174,6 +176,30 @@ struct tcp_md5sig {
|
|||
__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];
|
||||
};
|
||||
|
||||
#ifdef __KERNEL__
|
||||
|
||||
#include <linux/skbuff.h>
|
||||
|
@ -227,6 +253,11 @@ struct tcp_options_received {
|
|||
u16 mss_clamp; /* Maximal mss, negotiated at connection setup */
|
||||
};
|
||||
|
||||
static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
|
||||
{
|
||||
rx_opt->tstamp_ok = rx_opt->sack_ok = rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
|
||||
}
|
||||
|
||||
/* This is the max number of SACKS that we'll generate and process. It's safe
|
||||
* to increse this, although since:
|
||||
* size = TCPOLEN_SACK_BASE_ALIGNED (4) + n * TCPOLEN_SACK_PERBLOCK (8)
|
||||
|
@ -435,6 +466,6 @@ static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)
|
|||
return (struct tcp_timewait_sock *)sk;
|
||||
}
|
||||
|
||||
#endif
|
||||
#endif /* __KERNEL__ */
|
||||
|
||||
#endif /* _LINUX_TCP_H */
|
||||
|
|
|
@ -234,6 +234,7 @@ extern int sysctl_tcp_base_mss;
|
|||
extern int sysctl_tcp_workaround_signed_windows;
|
||||
extern int sysctl_tcp_slow_start_after_idle;
|
||||
extern int sysctl_tcp_max_ssthresh;
|
||||
extern int sysctl_tcp_cookie_size;
|
||||
|
||||
extern atomic_t tcp_memory_allocated;
|
||||
extern struct percpu_counter tcp_sockets_allocated;
|
||||
|
@ -340,11 +341,6 @@ static inline void tcp_dec_quickack_mode(struct sock *sk,
|
|||
|
||||
extern void tcp_enter_quickack_mode(struct sock *sk);
|
||||
|
||||
static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
|
||||
{
|
||||
rx_opt->tstamp_ok = rx_opt->sack_ok = rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
|
||||
}
|
||||
|
||||
#define TCP_ECN_OK 1
|
||||
#define TCP_ECN_QUEUE_CWR 2
|
||||
#define TCP_ECN_DEMAND_CWR 4
|
||||
|
|
|
@ -712,6 +712,14 @@ static struct ctl_table ipv4_table[] = {
|
|||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec,
|
||||
},
|
||||
{
|
||||
.ctl_name = CTL_UNNUMBERED,
|
||||
.procname = "tcp_cookie_size",
|
||||
.data = &sysctl_tcp_cookie_size,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec
|
||||
},
|
||||
{
|
||||
.ctl_name = CTL_UNNUMBERED,
|
||||
.procname = "udp_mem",
|
||||
|
|
|
@ -59,6 +59,9 @@ int sysctl_tcp_base_mss __read_mostly = 512;
|
|||
/* By default, RFC2861 behavior. */
|
||||
int sysctl_tcp_slow_start_after_idle __read_mostly = 1;
|
||||
|
||||
int sysctl_tcp_cookie_size __read_mostly = 0; /* TCP_COOKIE_MAX */
|
||||
|
||||
|
||||
/* Account for new data that has been sent to the network. */
|
||||
static void tcp_event_new_data_sent(struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
|
|
Loading…
Reference in New Issue