path: root/include/net/tcp.h
diff options
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2019-06-19 23:46:28 +0200
committerDavid S. Miller <davem@davemloft.net>2019-06-22 16:30:37 -0700
commit438ac88009bcb10f9ced07fbb4b32d5377ee936b (patch)
treea28dc489c5852e2894a04478bdd0f37ffe010ad5 /include/net/tcp.h
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net (diff)
net: fastopen: robustness and endianness fixes for SipHash
Some changes to the TCP fastopen code to make it more robust against future changes in the choice of key/cookie size, etc. - Instead of keeping the SipHash key in an untyped u8[] buffer and casting it to the right type upon use, use the correct type directly. This ensures that the key will appear at the correct alignment if we ever change the way these data structures are allocated. (Currently, they are only allocated via kmalloc so they always appear at the correct alignment) - Use DIV_ROUND_UP when sizing the u64[] array to hold the cookie, so it is always of sufficient size, even if TCP_FASTOPEN_COOKIE_MAX is no longer a multiple of 8. - Drop the 'len' parameter from the tcp_fastopen_reset_cipher() function, which is no longer used. - Add endian swabbing when setting the keys and calculating the hash, to ensure that cookie values are the same for a given key and source/destination address pair regardless of the endianness of the server. Note that none of these are functional changes wrt the current state of the code, with the exception of the swabbing, which only affects big endian systems. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 4 insertions, 4 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 573c9e9b0d72..9d36cc88d043 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -43,6 +43,7 @@
#include <linux/seq_file.h>
#include <linux/memcontrol.h>
#include <linux/bpf-cgroup.h>
+#include <linux/siphash.h>
extern struct inet_hashinfo tcp_hashinfo;
@@ -1612,8 +1613,7 @@ void tcp_free_fastopen_req(struct tcp_sock *tp);
void tcp_fastopen_destroy_cipher(struct sock *sk);
void tcp_fastopen_ctx_destroy(struct net *net);
int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk,
- void *primary_key, void *backup_key,
- unsigned int len);
+ void *primary_key, void *backup_key);
void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb);
struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb,
struct request_sock *req,
@@ -1623,14 +1623,14 @@ void tcp_fastopen_init_key_once(struct net *net);
bool tcp_fastopen_cookie_check(struct sock *sk, u16 *mss,
struct tcp_fastopen_cookie *cookie);
bool tcp_fastopen_defer_connect(struct sock *sk, int *err);
+#define TCP_FASTOPEN_KEY_LENGTH sizeof(siphash_key_t)
/* Fastopen key context */
struct tcp_fastopen_context {
+ siphash_key_t key[TCP_FASTOPEN_KEY_MAX];
int num;
struct rcu_head rcu;