Improve signature of ssl_compute_master()
Make it more explicit what's used. Unfortunately, we still need ssl as a
parameter for debugging, and because calc_verify wants it as a parameter (for
all TLS versions except SSL3 it would actually only need handshake, but SSL3
also accesses session_negotiate).
It's also because of calc_verify that we can't make it const yet, but see next
commit.
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index a78d6e5..15ce501 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1579,13 +1579,27 @@
/*
* Compute master secret if needed
+ *
+ * Parameters:
+ * [in/out] handshake
+ * [in] resume, premaster, extended_ms, calc_verify, tls_prf
+ * (PSA-PSK) ciphersuite_info
+ * [out] premaster (cleared)
+ * [in] minor_ver (to compute hash_len)
+ * [in] hash_alg (to compute hash_len)
+ * [out] master
+ * [in] ssl: optionally used for debugging, EMS and PSA-PSK
+ * debug: conf->f_dbg, conf->p_dbg
+ * EMS: passed to calc_verify (debug + (SSL3) session_negotiate)
+ * PSA-PSA: conf
*/
-static int ssl_compute_master( mbedtls_ssl_context *ssl )
+static int ssl_compute_master( mbedtls_ssl_handshake_params *handshake,
+ int minor_ver,
+ mbedtls_md_type_t hash_alg,
+ unsigned char *master,
+ mbedtls_ssl_context *ssl )
{
int ret;
- mbedtls_ssl_handshake_params *handshake = ssl->handshake;
- mbedtls_ssl_session *session = ssl->session_negotiate;
- const mbedtls_ssl_ciphersuite_t *ciphersuite_info = handshake->ciphersuite_info;
/* cf. RFC 5246, Section 8.1:
* "The master secret is always exactly 48 bytes in length." */
@@ -1611,6 +1625,19 @@
unsigned char const *salt = handshake->randbytes;
size_t salt_len = 64;
+#if !defined(MBEDTLS_DEBUG_C) && \
+ !defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) && \
+ !(defined(MBEDTLS_USE_PSA_CRYPTO) && \
+ defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED))
+ (void) ssl;
+#endif
+#if !defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) || !defined(MBEDTLS_SSL_PROTO_TLS1_2)
+ (void) minor_ver;
+#if defined(MBEDTLS_SHA512_C)
+ (void) hash_alg;
+#endif
+#endif
+
if( handshake->resume != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "no premaster (session resumed)" ) );
@@ -1618,18 +1645,18 @@
}
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
- if( ssl->handshake->extended_ms == MBEDTLS_SSL_EXTENDED_MS_ENABLED )
+ if( handshake->extended_ms == MBEDTLS_SSL_EXTENDED_MS_ENABLED )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "using extended master secret" ) );
lbl = "extended master secret";
salt = session_hash;
- ssl->handshake->calc_verify( ssl, session_hash );
+ handshake->calc_verify( ssl, session_hash );
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
- if( ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
+ if( minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 )
{
#if defined(MBEDTLS_SHA512_C)
- if( ciphersuite_info->mac == MBEDTLS_MD_SHA384 )
+ if( hash_alg == MBEDTLS_MD_SHA384 )
{
salt_len = 48;
}
@@ -1646,9 +1673,9 @@
#endif /* MBEDTLS_SSL_EXTENDED_MS_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
-defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
- if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK &&
- ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
+ defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
+ if( handshake->ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK &&
+ minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
ssl_use_opaque_psk( ssl ) == 1 )
{
/* Perform PSK-to-MS expansion in a single step. */
@@ -1661,10 +1688,10 @@
MBEDTLS_SSL_DEBUG_MSG( 2, ( "perform PSA-based PSK-to-MS expansion" ) );
psk = ssl->conf->psk_opaque;
- if( ssl->handshake->psk_opaque != 0 )
- psk = ssl->handshake->psk_opaque;
+ if( handshake->psk_opaque != 0 )
+ psk = handshake->psk_opaque;
- if( ciphersuite_info->mac == MBEDTLS_MD_SHA384 )
+ if( hash_alg == MBEDTLS_MD_SHA384 )
alg = PSA_ALG_TLS12_PSK_TO_MS(PSA_ALG_SHA_384);
else
alg = PSA_ALG_TLS12_PSK_TO_MS(PSA_ALG_SHA_256);
@@ -1681,7 +1708,7 @@
}
status = psa_key_derivation_output_bytes( &derivation,
- session->master,
+ master,
master_secret_len );
if( status != PSA_SUCCESS )
{
@@ -1698,7 +1725,7 @@
{
ret = handshake->tls_prf( handshake->premaster, handshake->pmslen,
lbl, salt, salt_len,
- session->master,
+ master,
master_secret_len );
if( ret != 0 )
{
@@ -1732,7 +1759,11 @@
return( ret );
}
- ret = ssl_compute_master( ssl );
+ ret = ssl_compute_master( ssl->handshake,
+ ssl->minor_ver,
+ ciphersuite_info->mac,
+ ssl->session_negotiate->master,
+ ssl );
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "ssl_compute_master", ret );
