Add ncr_symm_cipher_change_iv

3 files changed, 77 insertions, 0 deletions

diff --git a/include/ncrypto/ncrypto.h b/include/ncrypto/ncrypto.h
index 024d5a7..a09d451 100644
--- a/include/ncrypto/ncrypto.h
+++ b/include/ncrypto/ncrypto.h
@@ -158,6 +158,8 @@ struct ncr_symm_cipher_session;
 CK_RV ncr_symm_cipher_alloc (struct ncr_symm_cipher_session **sess,
 			     CK_MECHANISM_TYPE mech);
 CK_RV ncr_symm_cipher_free (struct ncr_symm_cipher_session *sess);
+CK_RV ncr_symm_cipher_change_iv (struct ncr_symm_cipher_session *sess,
+				 const void *iv, size_t iv_size);
 /* Use either ncr_symm_cipher_encrypt_{init,update,final} (), or
    ncr_symm_cipher_{encrypt_init,encrypt} ().  After finishing such a call
    sequence, a new sequence can be started within the same session.  Same for
diff --git a/lib/ncrypto_local.c b/lib/ncrypto_local.c
index da1ccab..537aaac 100644
--- a/lib/ncrypto_local.c
+++ b/lib/ncrypto_local.c
@@ -501,6 +501,25 @@ ncr_symm_cipher_free (struct ncr_symm_cipher_session *sess)
   return CKR_OK;
 }
 
+CK_RV
+ncr_symm_cipher_change_iv (struct ncr_symm_cipher_session *sess, const void *iv,
+			   size_t iv_size)
+{
+  g_return_val_if_fail (sess != NULL, CKR_SESSION_HANDLE_INVALID);
+  g_return_val_if_fail (sess->state == NSCS_INITIALIZED
+			|| sess->state == NSCS_UPDATED,
+			CKR_OPERATION_NOT_INITIALIZED);
+  g_return_val_if_fail (iv != NULL || iv_size == 0, CKR_ARGUMENTS_BAD);
+
+  g_return_val_if_fail (iv_size
+			== (unsigned)EVP_CIPHER_CTX_iv_length (&sess->ctx),
+			CKR_MECHANISM_PARAM_INVALID);
+  g_assert (iv_size <= sizeof (sess->ctx.iv));
+
+  memcpy (sess->ctx.iv, iv, iv_size);
+  return CKR_OK;
+}
+
 static CK_RV
 symm_cipher_init (struct ncr_symm_cipher_session *sess, bool encrypt,
 		  struct ncr_symm_key *key, const void *param,
diff --git a/tests/symm_ciphers.c b/tests/symm_ciphers.c
index a6f3570..2c2cd92 100644
--- a/tests/symm_ciphers.c
+++ b/tests/symm_ciphers.c
@@ -209,6 +209,62 @@ main (void)
       res = ncr_symm_cipher_alloc (&sess, tvs[i].mech);
       assert (res == CKR_OK);
 
+      res = ncr_symm_key_create (&key, tvs[i].key_type, true, tvs[i].key,
+				 tvs[i].key_size);
+      assert (res == CKR_OK);
+
+      res = ncr_symm_cipher_encrypt_init (sess, key, tvs[i].iv, tvs[i].iv_size);
+      assert (res == CKR_OK);
+
+      dest_size = sizeof (dest);
+      res = ncr_symm_cipher_encrypt_update (sess, dest, &dest_size,
+					    tvs[i].input, tvs[i].input_size);
+      assert (res == CKR_OK);
+      assert (dest_size == tvs[i].output_size);
+      assert (memcmp (dest, tvs[i].output, dest_size) == 0);
+
+      res = ncr_symm_cipher_change_iv (sess, tvs[i].iv, tvs[i].iv_size);
+      assert (res == CKR_OK);
+
+      dest_size = sizeof (dest);
+      res = ncr_symm_cipher_encrypt_final (sess, dest, &dest_size, tvs[i].input,
+					   tvs[i].input_size);
+      assert (res == CKR_OK);
+      assert (dest_size == tvs[i].output_size);
+      assert (memcmp (dest, tvs[i].output, dest_size) == 0);
+
+      res = ncr_symm_cipher_decrypt_init (sess, key, tvs[i].iv, tvs[i].iv_size);
+      assert (res == CKR_OK);
+
+      dest_size = sizeof (dest);
+      res = ncr_symm_cipher_decrypt_update (sess, dest, &dest_size,
+					    tvs[i].output, tvs[i].output_size);
+      assert (res == CKR_OK);
+      assert (dest_size == tvs[i].input_size);
+      assert (memcmp (dest, tvs[i].input, dest_size) == 0);
+
+      res = ncr_symm_cipher_change_iv (sess, tvs[i].iv, tvs[i].iv_size);
+      assert (res == CKR_OK);
+
+      dest_size = sizeof (dest);
+      res = ncr_symm_cipher_decrypt_final (sess, dest, &dest_size,
+					   tvs[i].output, tvs[i].output_size);
+      assert (res == CKR_OK);
+      assert (dest_size == tvs[i].input_size);
+      assert (memcmp (dest, tvs[i].input, dest_size) == 0);
+
+      res = ncr_symm_key_destroy (key);
+      assert (res == CKR_OK);
+
+      res = ncr_symm_cipher_free (sess);
+      assert (res == CKR_OK);
+    }
+
+  for (i = 0; i < G_N_ELEMENTS (tvs); i++)
+    {
+      res = ncr_symm_cipher_alloc (&sess, tvs[i].mech);
+      assert (res == CKR_OK);
+
       res = ncr_symm_key_generate (&key, tvs[i].key_gen_mech, true,
 				   tvs[i].key_size);
       assert (res == CKR_OK);