Introduce zlen size variable in ECHDE-PSK part of ssl_write_client_key_exchange()
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/library/ssl_tls12_client.c b/library/ssl_tls12_client.c
index 91cad8b..d372663 100644
--- a/library/ssl_tls12_client.c
+++ b/library/ssl_tls12_client.c
@@ -3098,6 +3098,8 @@
unsigned char *p = ssl->handshake->premaster;
const unsigned char* const p_end = p +
sizeof( ssl->handshake->premaster );
+ /* uint16 to store length (in octets) of the ECDH computation */
+ const size_t zlen_size = 2;
size_t zlen = 0;
/* Perform ECDH computation after the uint16 reserved for the length */
@@ -3105,8 +3107,8 @@
handshake->ecdh_psa_privkey,
handshake->ecdh_psa_peerkey,
handshake->ecdh_psa_peerkey_len,
- p + 2,
- p_end - ( p + 2 ),
+ p + zlen_size,
+ p_end - ( p + zlen_size ),
&zlen );
destruction_status = psa_destroy_key( handshake->ecdh_psa_privkey );
@@ -3119,7 +3121,7 @@
/* Write the ECDH computation length before the ECDH computation */
MBEDTLS_PUT_UINT16_BE( zlen, p, 0 );
- p += 2 + zlen;
+ p += zlen_size + zlen;
/* opaque psk<0..2^16-1>; */
if( p_end - p < 2 )