bootutil: Enc uses one context type for key exchange

Signed-off-by: Dominik Ermel <[email protected]>

Author: de-nordic

boot/bootutil/include/bootutil/crypto/ecdh_p256.h

@@ -35,6 +35,7 @@ extern "C" {
 
 #if defined(MCUBOOT_USE_TINYCRYPT)
 typedef uintptr_t bootutil_ecdh_p256_context;
+typedef bootutil_ecdh_p256_context bootutil_key_xchange_ctx;
 static inline void bootutil_ecdh_p256_init(bootutil_ecdh_p256_context *ctx)
 {
     (void)ctx;

boot/bootutil/include/bootutil/crypto/ecdh_x25519.h

@@ -26,6 +26,7 @@ extern int X25519(uint8_t out_shared_key[32], const uint8_t private_key[32],
                   const uint8_t peer_public_value[32]);
 
 typedef uintptr_t bootutil_ecdh_x25519_context;
+typedef bootutil_ecdh_x25519_context bootutil_key_xchange_ctx;
 static inline void bootutil_ecdh_x25519_init(bootutil_ecdh_x25519_context *ctx)
 {
     (void)ctx;

boot/bootutil/include/bootutil/crypto/rsa.h

@@ -68,6 +68,7 @@ extern "C" {
 typedef struct {
     psa_key_id_t key_id;
 } bootutil_rsa_context;
+typedef bootutil_rsa_context bootutil_key_xchange_ctx;
 
 static inline void bootutil_rsa_init(bootutil_rsa_context *ctx)
 {
@@ -176,6 +177,7 @@ static inline int bootutil_rsassa_pss_verify(const bootutil_rsa_context *ctx,
 #elif defined(MCUBOOT_USE_MBED_TLS)
 
 typedef mbedtls_rsa_context bootutil_rsa_context;
+typedef bootutil_rsa_context bootutil_key_xchange_ctx;
 
 static inline void bootutil_rsa_init(bootutil_rsa_context *ctx)
 {

boot/bootutil/src/encrypted.c

@@ -405,15 +405,7 @@ static int fake_rng(void *p_rng, unsigned char *output, size_t len)
 int
 boot_decrypt_key(const uint8_t *buf, uint8_t *enckey)
 {
-#if defined(MCUBOOT_ENCRYPT_RSA)
-    bootutil_rsa_context            pk_ctx;
-#endif
-#if defined(MCUBOOT_ENCRYPT_EC256)
-    bootutil_ecdh_p256_context      pk_ctx;
-#endif
-#if defined(MCUBOOT_ENCRYPT_X25519)
-    bootutil_ecdh_x25519_context    pk_ctx;
-#endif
+    bootutil_key_exchange_ctx       pk_ctx;
 #if defined(MCUBOOT_ENCRYPT_EC256) || defined(MCUBOOT_ENCRYPT_X25519)
     bootutil_hmac_sha256_context hmac;
     bootutil_aes_ctr_context aes_ctr;