1 files changed, 62 insertions, 10 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 61723a7c21fe..7fee8a4df931 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -81,6 +81,12 @@ enum {
         TCP_DATA_OFFSET = __cpu_to_be32(0xF0000000)
 }; 
 
+/*
+ * TCP general constants
+ */
+#define TCP_MSS_DEFAULT          536U   /* IPv4 (RFC1122, RFC2581) */
+#define TCP_MSS_DESIRED         1220U   /* IPv6 (tunneled), EDNS0 (RFC3226) */
+
 /* TCP socket options */
 #define TCP_NODELAY             1       /* Turn off Nagle's algorithm. */
 #define TCP_MAXSEG              2       /* Limit MSS */
@@ -96,14 +102,15 @@ 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
 #define TCPI_OPT_ECN            8
 
-enum tcp_ca_state
-{
+enum tcp_ca_state {
         TCP_CA_Open = 0,
 #define TCPF_CA_Open    (1<<TCP_CA_Open)
         TCP_CA_Disorder = 1,
@@ -116,8 +123,7 @@ enum tcp_ca_state
 #define TCPF_CA_Loss    (1<<TCP_CA_Loss)
 };
 
-struct tcp_info
-{
+struct tcp_info {
         __u8    tcpi_state;
         __u8    tcpi_ca_state;
         __u8    tcpi_retransmits;
@@ -170,6 +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>
@@ -217,26 +247,38 @@ struct tcp_options_received {
                 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   */
-/*      SACKs data      */
+        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     user_mss;       /* mss requested by user in ioctl       */
         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 = 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
- * to increse this, although since:
+ * to increase this, although since:
  *   size = TCPOLEN_SACK_BASE_ALIGNED (4) + n * TCPOLEN_SACK_PERBLOCK (8)
  * only four options will fit in a standard TCP header */
 #define TCP_NUM_SACKS 4
 
+struct tcp_cookie_values;
+struct tcp_request_sock_ops;
+
 struct tcp_request_sock {
         struct inet_request_sock        req;
 #ifdef CONFIG_TCP_MD5SIG
         /* Only used by TCP MD5 Signature so far. */
         const struct tcp_request_sock_ops *af_specific;
 #endif
-        u32                             rcv_isn;
-        u32                             snt_isn;
+        u32                             rcv_isn;
+        u32                             snt_isn;
 };
 
 static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req)
@@ -406,6 +448,12 @@ struct tcp_sock {
 /* TCP MD5 Signature Option information */
         struct tcp_md5sig_info  *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;
 };
 
 static inline struct tcp_sock *tcp_sk(const struct sock *sk)
@@ -424,6 +472,10 @@ struct tcp_timewait_sock {
         u16                       tw_md5_keylen;
         u8                        tw_md5_key[TCP_MD5SIG_MAXKEYLEN];
 #endif
+        /* Few sockets in timewait have cookies; in that case, then this
+         * object holds a reference to them (tw_cookie_values->kref).
+         */
+        struct tcp_cookie_values  *tw_cookie_values;
 };
 
 static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk)
@@ -431,6 +483,6 @@ 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 */