Fix seal/open, ECB mode does not use an IV.

Change-Id: I953bf874f2bb760d129e90dac3246c9f24e0c5ec

diff --git a/src/seal.c b/src/seal.c
index c07fe3f..7dd3ba8 100644 (file)
--- a/src/seal.c
+++ b/src/seal.c
@@ -110,6 +110,9 @@ static int seal_init(yaca_ctx_h *ctx,
        struct yaca_seal_ctx_s *nc;
        const EVP_CIPHER *cipher;
        int pub_key_length;
+       unsigned char *key_data = NULL;
+       int key_data_length;
+       unsigned char *iv_data = NULL;
        int iv_length;
        int ret;
 
@@ -150,6 +153,7 @@ static int seal_init(yaca_ctx_h *ctx,
                ret = YACA_ERROR_OUT_OF_MEMORY;
                goto exit;
        }
+       key_data = (unsigned char*)lkey->d;
 
        ret = encrypt_get_algorithm(algo, bcm, sym_key_bits, &cipher);
        if (ret != YACA_ERROR_NONE)
@@ -163,20 +167,20 @@ static int seal_init(yaca_ctx_h *ctx,
        }
 
        iv_length = ret;
-       liv = yaca_zalloc(sizeof(struct yaca_key_simple_s) + iv_length);
-       if (liv == NULL) {
-               ret = YACA_ERROR_OUT_OF_MEMORY;
-               goto exit;
+       if (iv_length > 0) {
+               liv = yaca_zalloc(sizeof(struct yaca_key_simple_s) + iv_length);
+               if (liv == NULL) {
+                       ret = YACA_ERROR_OUT_OF_MEMORY;
+                       goto exit;
+               }
+               iv_data = (unsigned char*)liv->d;
        }
 
-       unsigned char *key_data = (unsigned char*)lkey->d;
-       int key_data_length;
-
        ret = EVP_SealInit(nc->cipher_ctx,
                           cipher,
                           &key_data,
                           &key_data_length,
-                          (unsigned char*)liv->d,
+                          iv_data,
                           &lpub->evp,
                           1);
 
@@ -191,11 +195,14 @@ static int seal_init(yaca_ctx_h *ctx,
        *sym_key = (yaca_key_h)lkey;
        lkey = NULL;
 
-       liv->bits = iv_length * 8;
-       liv->key.type = YACA_KEY_TYPE_IV;
-       *iv = (yaca_key_h)liv;
-       liv = NULL;
-
+       if (iv_length > 0) {
+               liv->bits = iv_length * 8;
+               liv->key.type = YACA_KEY_TYPE_IV;
+               *iv = (yaca_key_h)liv;
+               liv = NULL;
+       } else {
+               *iv = NULL;
+       }
        *ctx = (yaca_ctx_h)nc;
        nc = NULL;
        ret = YACA_ERROR_NONE;
@@ -221,6 +228,7 @@ static int open_init(yaca_ctx_h *ctx,
        const struct yaca_key_simple_s *liv;
        struct yaca_seal_ctx_s *nc;
        const EVP_CIPHER *cipher;
+       unsigned char *iv_data = NULL;
        size_t iv_bits;
        size_t iv_bits_check;
        int ret;
@@ -263,22 +271,23 @@ static int open_init(yaca_ctx_h *ctx,
                goto exit;
        }
 
-       liv = key_get_simple(iv);
-       /* cipher requires iv, but none was provided, or provided wrong iv */
-       if (iv_bits != 0 && (liv == NULL || liv->key.type != YACA_KEY_TYPE_IV)) {
-               ret = YACA_ERROR_INVALID_ARGUMENT;
-               goto exit;
-       }
-
-       // TODO: handling of algorithms with variable IV length
-       ret = yaca_key_get_bits(iv, &iv_bits_check);
-       if (ret != YACA_ERROR_NONE) {
-               ret = YACA_ERROR_INVALID_ARGUMENT;
-               goto exit;
-       }
-       if (iv_bits != iv_bits_check) { /* IV length doesn't match cipher */
-               ret = YACA_ERROR_INVALID_ARGUMENT;
-               goto exit;
+       if (iv_bits > 0) { /* cipher requires iv*/
+               liv = key_get_simple(iv);
+               if (liv == NULL || liv->key.type != YACA_KEY_TYPE_IV) { /* iv was not provided */
+                       ret = YACA_ERROR_INVALID_ARGUMENT;
+                       goto exit;
+               }
+               ret = yaca_key_get_bits(iv, &iv_bits_check);
+               if (ret != YACA_ERROR_NONE) {
+                       ret = YACA_ERROR_INVALID_ARGUMENT;
+                       goto exit;
+               }
+               /* IV length doesn't match cipher */
+               if (iv_bits != iv_bits_check) {
+                       ret = YACA_ERROR_INVALID_ARGUMENT;
+                       goto exit;
+               }
+               iv_data = (unsigned char*)liv->d;
        }
 
        nc->cipher_ctx = EVP_CIPHER_CTX_new();
@@ -291,7 +300,7 @@ static int open_init(yaca_ctx_h *ctx,
        ret = EVP_OpenInit(nc->cipher_ctx, cipher,
                           (unsigned char*)lkey->d,
                           EVP_PKEY_size(lprv->evp),
-                          (unsigned char*)liv->d,
+                          iv_data,
                           lprv->evp);
        if (ret != 1) {
                ret = YACA_ERROR_INTERNAL;