tcp md5sig: Share MD5 Signature option parser between IPv4 and IPv6.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 633147c..b1c4b78 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -399,6 +399,8 @@
struct tcp_options_received *opt_rx,
int estab);
+extern u8 *tcp_parse_md5sig_option(struct tcphdr *th);
+
/*
* TCP v4 functions exported for the inet6 API
*/
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index eba873e9..f331e67 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3450,6 +3450,43 @@
return 1;
}
+#ifdef CONFIG_TCP_MD5SIG
+/*
+ * Parse MD5 Signature option
+ */
+u8 *tcp_parse_md5sig_option(struct tcphdr *th)
+{
+ int length = (th->doff << 2) - sizeof (*th);
+ u8 *ptr = (u8*)(th + 1);
+
+ /* If the TCP option is too short, we can short cut */
+ if (length < TCPOLEN_MD5SIG)
+ return NULL;
+
+ while (length > 0) {
+ int opcode = *ptr++;
+ int opsize;
+
+ switch(opcode) {
+ case TCPOPT_EOL:
+ return NULL;
+ case TCPOPT_NOP:
+ length--;
+ continue;
+ default:
+ opsize = *ptr++;
+ if (opsize < 2 || opsize > length)
+ return NULL;
+ if (opcode == TCPOPT_MD5SIG)
+ return ptr;
+ }
+ ptr += opsize - 2;
+ length -= opsize;
+ }
+ return NULL;
+}
+#endif
+
static inline void tcp_store_ts_recent(struct tcp_sock *tp)
{
tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval;
@@ -5467,6 +5504,9 @@
EXPORT_SYMBOL(sysctl_tcp_reordering);
EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
EXPORT_SYMBOL(tcp_parse_options);
+#ifdef CONFIG_TCP_MD5SIG
+EXPORT_SYMBOL(tcp_parse_md5sig_option);
+#endif
EXPORT_SYMBOL(tcp_rcv_established);
EXPORT_SYMBOL(tcp_rcv_state_process);
EXPORT_SYMBOL(tcp_initialize_rcv_mss);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index cd601a8..56f5509 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1134,52 +1134,12 @@
struct tcp_md5sig_key *hash_expected;
const struct iphdr *iph = ip_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
- int length = (th->doff << 2) - sizeof(struct tcphdr);
int genhash;
- unsigned char *ptr;
unsigned char newhash[16];
hash_expected = tcp_v4_md5_do_lookup(sk, iph->saddr);
+ hash_location = tcp_parse_md5sig_option(th);
- /*
- * If the TCP option length is less than the TCP_MD5SIG
- * option length, then we can shortcut
- */
- if (length < TCPOLEN_MD5SIG) {
- if (hash_expected)
- return 1;
- else
- return 0;
- }
-
- /* Okay, we can't shortcut - we have to grub through the options */
- ptr = (unsigned char *)(th + 1);
- while (length > 0) {
- int opcode = *ptr++;
- int opsize;
-
- switch (opcode) {
- case TCPOPT_EOL:
- goto done_opts;
- case TCPOPT_NOP:
- length--;
- continue;
- default:
- opsize = *ptr++;
- if (opsize < 2)
- goto done_opts;
- if (opsize > length)
- goto done_opts;
-
- if (opcode == TCPOPT_MD5SIG) {
- hash_location = ptr;
- goto done_opts;
- }
- }
- ptr += opsize-2;
- length -= opsize;
- }
-done_opts:
/* We've parsed the options - do we have a hash? */
if (!hash_expected && !hash_location)
return 0;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 715965f..dd4ddb3 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -844,43 +844,12 @@
struct tcp_md5sig_key *hash_expected;
struct ipv6hdr *ip6h = ipv6_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
- int length = (th->doff << 2) - sizeof (*th);
int genhash;
- u8 *ptr;
u8 newhash[16];
hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
+ hash_location = tcp_parse_md5sig_option(th);
- /* If the TCP option is too short, we can short cut */
- if (length < TCPOLEN_MD5SIG)
- return hash_expected ? 1 : 0;
-
- /* parse options */
- ptr = (u8*)(th + 1);
- while (length > 0) {
- int opcode = *ptr++;
- int opsize;
-
- switch(opcode) {
- case TCPOPT_EOL:
- goto done_opts;
- case TCPOPT_NOP:
- length--;
- continue;
- default:
- opsize = *ptr++;
- if (opsize < 2 || opsize > length)
- goto done_opts;
- if (opcode == TCPOPT_MD5SIG) {
- hash_location = ptr;
- goto done_opts;
- }
- }
- ptr += opsize - 2;
- length -= opsize;
- }
-
-done_opts:
/* do we have a hash as expected? */
if (!hash_expected) {
if (!hash_location)
