move psk_derive_premaster

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index ce111f9..9af6ced 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1009,132 +1009,6 @@
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
 
-#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
-int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex )
-{
-    unsigned char *p = ssl->handshake->premaster;
-    unsigned char *end = p + sizeof( ssl->handshake->premaster );
-    const unsigned char *psk = NULL;
-    size_t psk_len = 0;
-
-    if( mbedtls_ssl_get_psk( ssl, &psk, &psk_len )
-            == MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED )
-    {
-        /*
-         * This should never happen because the existence of a PSK is always
-         * checked before calling this function
-         */
-        MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
-        return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
-    }
-
-    /*
-     * PMS = struct {
-     *     opaque other_secret<0..2^16-1>;
-     *     opaque psk<0..2^16-1>;
-     * };
-     * with "other_secret" depending on the particular key exchange
-     */
-#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
-    if( key_ex == MBEDTLS_KEY_EXCHANGE_PSK )
-    {
-        if( end - p < 2 )
-            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
-
-        MBEDTLS_PUT_UINT16_BE( psk_len, p, 0 );
-        p += 2;
-
-        if( end < p || (size_t)( end - p ) < psk_len )
-            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
-
-        memset( p, 0, psk_len );
-        p += psk_len;
-    }
-    else
-#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */
-#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
-    if( key_ex == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
-    {
-        /*
-         * other_secret already set by the ClientKeyExchange message,
-         * and is 48 bytes long
-         */
-        if( end - p < 2 )
-            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
-
-        *p++ = 0;
-        *p++ = 48;
-        p += 48;
-    }
-    else
-#endif /* MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
-#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
-    if( key_ex == MBEDTLS_KEY_EXCHANGE_DHE_PSK )
-    {
-        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-        size_t len;
-
-        /* Write length only when we know the actual value */
-        if( ( ret = mbedtls_dhm_calc_secret( &ssl->handshake->dhm_ctx,
-                                      p + 2, end - ( p + 2 ), &len,
-                                      ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
-        {
-            MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_calc_secret", ret );
-            return( ret );
-        }
-        MBEDTLS_PUT_UINT16_BE( len, p, 0 );
-        p += 2 + len;
-
-        MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K  );
-    }
-    else
-#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
-#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
-    if( key_ex == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
-    {
-        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-        size_t zlen;
-
-        if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &zlen,
-                                       p + 2, end - ( p + 2 ),
-                                       ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
-        {
-            MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_calc_secret", ret );
-            return( ret );
-        }
-
-        MBEDTLS_PUT_UINT16_BE( zlen, p, 0 );
-        p += 2 + zlen;
-
-        MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
-                                MBEDTLS_DEBUG_ECDH_Z );
-    }
-    else
-#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
-        return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
-    }
-
-    /* opaque psk<0..2^16-1>; */
-    if( end - p < 2 )
-        return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
-
-    MBEDTLS_PUT_UINT16_BE( psk_len, p, 0 );
-    p += 2;
-
-    if( end < p || (size_t)( end - p ) < psk_len )
-        return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
-
-    memcpy( p, psk, psk_len );
-    p += psk_len;
-
-    ssl->handshake->pmslen = p - ssl->handshake->premaster;
-
-    return( 0 );
-}
-#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
-
 #if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_RENEGOTIATION)
 static int ssl_write_hello_request( mbedtls_ssl_context *ssl );
 
@@ -7966,6 +7840,131 @@
 }
 #endif /* MBEDTLS_SHA384_C */
 
+#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
+int mbedtls_ssl_psk_derive_premaster( mbedtls_ssl_context *ssl, mbedtls_key_exchange_type_t key_ex )
+{
+    unsigned char *p = ssl->handshake->premaster;
+    unsigned char *end = p + sizeof( ssl->handshake->premaster );
+    const unsigned char *psk = NULL;
+    size_t psk_len = 0;
+
+    if( mbedtls_ssl_get_psk( ssl, &psk, &psk_len )
+            == MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED )
+    {
+        /*
+         * This should never happen because the existence of a PSK is always
+         * checked before calling this function
+         */
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
+        return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+    }
+
+    /*
+     * PMS = struct {
+     *     opaque other_secret<0..2^16-1>;
+     *     opaque psk<0..2^16-1>;
+     * };
+     * with "other_secret" depending on the particular key exchange
+     */
+#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
+    if( key_ex == MBEDTLS_KEY_EXCHANGE_PSK )
+    {
+        if( end - p < 2 )
+            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+
+        MBEDTLS_PUT_UINT16_BE( psk_len, p, 0 );
+        p += 2;
+
+        if( end < p || (size_t)( end - p ) < psk_len )
+            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+
+        memset( p, 0, psk_len );
+        p += psk_len;
+    }
+    else
+#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */
+#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
+    if( key_ex == MBEDTLS_KEY_EXCHANGE_RSA_PSK )
+    {
+        /*
+         * other_secret already set by the ClientKeyExchange message,
+         * and is 48 bytes long
+         */
+        if( end - p < 2 )
+            return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+
+        *p++ = 0;
+        *p++ = 48;
+        p += 48;
+    }
+    else
+#endif /* MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
+#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
+    if( key_ex == MBEDTLS_KEY_EXCHANGE_DHE_PSK )
+    {
+        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+        size_t len;
+
+        /* Write length only when we know the actual value */
+        if( ( ret = mbedtls_dhm_calc_secret( &ssl->handshake->dhm_ctx,
+                                      p + 2, end - ( p + 2 ), &len,
+                                      ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
+        {
+            MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_dhm_calc_secret", ret );
+            return( ret );
+        }
+        MBEDTLS_PUT_UINT16_BE( len, p, 0 );
+        p += 2 + len;
+
+        MBEDTLS_SSL_DEBUG_MPI( 3, "DHM: K ", &ssl->handshake->dhm_ctx.K  );
+    }
+    else
+#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
+#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
+    if( key_ex == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
+    {
+        int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+        size_t zlen;
+
+        if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx, &zlen,
+                                       p + 2, end - ( p + 2 ),
+                                       ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
+        {
+            MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_calc_secret", ret );
+            return( ret );
+        }
+
+        MBEDTLS_PUT_UINT16_BE( zlen, p, 0 );
+        p += 2 + zlen;
+
+        MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
+                                MBEDTLS_DEBUG_ECDH_Z );
+    }
+    else
+#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
+        return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+    }
+
+    /* opaque psk<0..2^16-1>; */
+    if( end - p < 2 )
+        return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+
+    MBEDTLS_PUT_UINT16_BE( psk_len, p, 0 );
+    p += 2;
+
+    if( end < p || (size_t)( end - p ) < psk_len )
+        return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+
+    memcpy( p, psk, psk_len );
+    p += psk_len;
+
+    ssl->handshake->pmslen = p - ssl->handshake->premaster;
+
+    return( 0 );
+}
+#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
 
 #endif /* MBEDTLS_SSL_TLS_C */