[PATCH v5 04/20] tcp: md5: Refactor tcp_sig_hash_skb_data for AO

From: Leonard Crestez
Date: Mon Jan 24 2022 - 07:14:20 EST


This chunk of code is identical between the implementation of TCP-MD5
and TCP-AO so rename and refactor

Signed-off-by: Leonard Crestez <cdleonard@xxxxxxxxx>
---
include/net/tcp.h | 2 +-
net/ipv4/tcp.c | 38 ++++++++++++++++++++------------------
net/ipv4/tcp_ipv4.c | 2 +-
net/ipv6/tcp_ipv6.c | 2 +-
4 files changed, 23 insertions(+), 21 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 6cc2eeb45deb..1a0513b0ead0 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1688,11 +1688,11 @@ struct tcp_md5sig_pool *tcp_get_md5sig_pool(void);
static inline void tcp_put_md5sig_pool(void)
{
local_bh_enable();
}

-int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *, const struct sk_buff *,
+int tcp_sig_hash_skb_data(struct ahash_request *, const struct sk_buff *,
unsigned int header_len);
int tcp_md5_hash_key(struct tcp_md5sig_pool *hp,
const struct tcp_md5sig_key *key);

/* From tcp_fastopen.c */
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 3651a1e13a16..f00f67d1f2b0 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4399,16 +4399,31 @@ struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
local_bh_enable();
return NULL;
}
EXPORT_SYMBOL(tcp_get_md5sig_pool);

-int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp,
+int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key)
+{
+ u8 keylen = READ_ONCE(key->keylen); /* paired with WRITE_ONCE() in tcp_md5_do_add */
+ struct scatterlist sg;
+
+ sg_init_one(&sg, key->key, keylen);
+ ahash_request_set_crypt(hp->md5_req, &sg, NULL, keylen);
+
+ /* We use data_race() because tcp_md5_do_add() might change key->key under us */
+ return data_race(crypto_ahash_update(hp->md5_req));
+}
+EXPORT_SYMBOL(tcp_md5_hash_key);
+#endif /* CONFIG_TCP_MD5SIG */
+
+#if defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AUTHOPT)
+
+int tcp_sig_hash_skb_data(struct ahash_request *req,
const struct sk_buff *skb, unsigned int header_len)
{
struct scatterlist sg;
const struct tcphdr *tp = tcp_hdr(skb);
- struct ahash_request *req = hp->md5_req;
unsigned int i;
const unsigned int head_data_len = skb_headlen(skb) > header_len ?
skb_headlen(skb) - header_len : 0;
const struct skb_shared_info *shi = skb_shinfo(skb);
struct sk_buff *frag_iter;
@@ -4431,31 +4446,18 @@ int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp,
if (crypto_ahash_update(req))
return 1;
}

skb_walk_frags(skb, frag_iter)
- if (tcp_md5_hash_skb_data(hp, frag_iter, 0))
+ if (tcp_sig_hash_skb_data(req, frag_iter, 0))
return 1;

return 0;
}
-EXPORT_SYMBOL(tcp_md5_hash_skb_data);
+EXPORT_SYMBOL(tcp_sig_hash_skb_data);

-int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key)
-{
- u8 keylen = READ_ONCE(key->keylen); /* paired with WRITE_ONCE() in tcp_md5_do_add */
- struct scatterlist sg;
-
- sg_init_one(&sg, key->key, keylen);
- ahash_request_set_crypt(hp->md5_req, &sg, NULL, keylen);
-
- /* We use data_race() because tcp_md5_do_add() might change key->key under us */
- return data_race(crypto_ahash_update(hp->md5_req));
-}
-EXPORT_SYMBOL(tcp_md5_hash_key);
-
-#endif
+#endif /* defined(CONFIG_TCP_MD5SIG) || defined(CONFIG_TCP_AUTHOPT) */

void tcp_done(struct sock *sk)
{
struct request_sock *req;

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index f03d48e574c9..442c28e1c72a 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1381,11 +1381,11 @@ int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key,
if (crypto_ahash_init(req))
goto clear_hash;

if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len))
goto clear_hash;
- if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
+ if (tcp_sig_hash_skb_data(hp->md5_req, skb, th->doff << 2))
goto clear_hash;
if (tcp_md5_hash_key(hp, key))
goto clear_hash;
ahash_request_set_crypt(req, NULL, md5_hash, 0);
if (crypto_ahash_final(req))
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 075ee8a2df3b..7aed4cdfcd65 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -750,11 +750,11 @@ static int tcp_v6_md5_hash_skb(char *md5_hash,
if (crypto_ahash_init(req))
goto clear_hash;

if (tcp_v6_md5_hash_headers(hp, daddr, saddr, th, skb->len))
goto clear_hash;
- if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
+ if (tcp_sig_hash_skb_data(hp->md5_req, skb, th->doff << 2))
goto clear_hash;
if (tcp_md5_hash_key(hp, key))
goto clear_hash;
ahash_request_set_crypt(req, NULL, md5_hash, 0);
if (crypto_ahash_final(req))
--
2.25.1