ccm_decrypt_message: length argument is cleartext (dst) length

Also updated related functions.

diff --git a/ChangeLog b/ChangeLog
index 12ddbc7001a19f658ce9a24fada83b6a3e8c798f..2a43a3cb684c82ccbd8840b40ac1057256b893df 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2014-04-25  Niels Möller  <nisse@lysator.liu.se>
+
+       * testsuite/ccm-test.c (test_cipher_ccm): And tests.
+
+       * ccm.c (ccm_decrypt_message): Change length argument, should now
+       be clear text (dst) length.
+       * ccm-aes128.c (ccm_aes128_decrypt_message): Likewise.
+       * ccm-aes192.c (ccm_aes192_decrypt_message): Likewise.
+       * ccm-aes256.c (ccm_aes256_decrypt_message): Likewise.
+       * ccm.h: Updated prototypes.
+
 2014-04-22  Niels Möller  <nisse@lysator.liu.se>
 
        * nettle.texinfo (Recommended hash functions): Document additional

diff --git a/ccm-aes128.c b/ccm-aes128.c
index c47249ea8ae32257bbfd44a0971d0cf8046ce96d..74ae51f4c7eac491ec1f532f8776b15e8dc8ab4e 100644 (file)
--- a/ccm-aes128.c
+++ b/ccm-aes128.c
@@ -105,10 +105,10 @@ ccm_aes128_decrypt_message(struct ccm_aes128_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src)
+                          size_t mlength, uint8_t *dst, const uint8_t *src)
 {
   return ccm_decrypt_message(&ctx->cipher,
                             (nettle_cipher_func *) aes128_encrypt,
                             nlength, nonce, alength, adata,
-                            tlength, clength, dst, src);
+                            tlength, mlength, dst, src);
 }

diff --git a/ccm-aes192.c b/ccm-aes192.c
index 01d406a0d87f1da1f43ce83862df103c5d035277..6b6ebed94abf2a69b9a650e3fae07c9eca4ccbfc 100644 (file)
--- a/ccm-aes192.c
+++ b/ccm-aes192.c
@@ -105,10 +105,10 @@ ccm_aes192_decrypt_message(struct ccm_aes192_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src)
+                          size_t mlength, uint8_t *dst, const uint8_t *src)
 {
   return ccm_decrypt_message(&ctx->cipher,
                             (nettle_cipher_func *) aes192_encrypt,
                             nlength, nonce, alength, adata,
-                            tlength, clength, dst, src);
+                            tlength, mlength, dst, src);
 }

diff --git a/ccm-aes256.c b/ccm-aes256.c
index 9a58ceabee7cb25bec145a42ba2f1df414ac2185..211c411b3200f066d748f444e4995e78637adbb4 100644 (file)
--- a/ccm-aes256.c
+++ b/ccm-aes256.c
@@ -106,9 +106,9 @@ ccm_aes256_decrypt_message(struct ccm_aes256_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src)
+                          size_t mlength, uint8_t *dst, const uint8_t *src)
 {
   return ccm_decrypt_message(&ctx->cipher, (nettle_cipher_func *) aes256_encrypt,
                             nlength, nonce, alength, adata,
-                            tlength, clength, dst, src);
+                            tlength, mlength, dst, src);
 }

diff --git a/ccm.c b/ccm.c
index 496559145ff8cec06da6db2c2fc242a730db5569..00f3f26e4ad51c38305382eff4e5257acbd06380 100644 (file)
--- a/ccm.c
+++ b/ccm.c
@@ -250,14 +250,13 @@ int
 ccm_decrypt_message(const void *cipher, nettle_cipher_func *f,
                    size_t nlength, const uint8_t *nonce,
                    size_t alength, const uint8_t *adata, size_t tlength,
-                   size_t clength, uint8_t *dst, const uint8_t *src)
+                   size_t mlength, uint8_t *dst, const uint8_t *src)
 {
   struct ccm_ctx ctx;
   uint8_t tag[CCM_BLOCK_SIZE];
-  assert(clength >= tlength);
-  ccm_set_nonce(&ctx, cipher, f, nlength, nonce, alength, clength-tlength, tlength);
+  ccm_set_nonce(&ctx, cipher, f, nlength, nonce, alength, mlength, tlength);
   ccm_update(&ctx, cipher, f, alength, adata);
-  ccm_decrypt(&ctx, cipher, f, clength-tlength, dst, src);
+  ccm_decrypt(&ctx, cipher, f, mlength, dst, src);
   ccm_digest(&ctx, cipher, f, tlength, tag);
-  return (memcmp(tag, src + (clength-tlength), tlength) == 0);
+  return (memcmp(tag, src + mlength, tlength) == 0);
 }

diff --git a/ccm.h b/ccm.h
index b215360d8555775797b04e4a2d888973fc9203e7..9827e45db9dfc7d9dab11cd9112a1bfe3f080be7 100644 (file)
--- a/ccm.h
+++ b/ccm.h
@@ -150,7 +150,7 @@ ccm_decrypt_message(const void *cipher, nettle_cipher_func *f,
                    size_t nlength, const uint8_t *nonce,
                    size_t alength, const uint8_t *adata,
                    size_t tlength,
-                   size_t clength, uint8_t *dst, const uint8_t *src);
+                   size_t mlength, uint8_t *dst, const uint8_t *src);
 
 /* CCM Mode with AES-128 */
 struct ccm_aes128_ctx {
@@ -194,7 +194,7 @@ ccm_aes128_decrypt_message(struct ccm_aes128_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src);
+                          size_t mlength, uint8_t *dst, const uint8_t *src);
 
 struct ccm_aes192_ctx {
     struct ccm_ctx      ccm;
@@ -238,7 +238,7 @@ ccm_aes192_decrypt_message(struct ccm_aes192_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src);
+                          size_t mlength, uint8_t *dst, const uint8_t *src);
 
 /* CCM Mode with AES-256 */
 struct ccm_aes256_ctx {
@@ -282,7 +282,7 @@ ccm_aes256_decrypt_message(struct ccm_aes256_ctx *ctx,
                           size_t nlength, const uint8_t *nonce,
                           size_t alength, const uint8_t *adata,
                           size_t tlength,
-                          size_t clength, uint8_t *dst, const uint8_t *src);
+                          size_t mlength, uint8_t *dst, const uint8_t *src);
 
 #ifdef __cplusplus
 }

diff --git a/testsuite/ccm-test.c b/testsuite/ccm-test.c
index 9a7161b9c9108ca2c107b6bc60644c6beff8c099..4176cc7fbcbf450522a6b8e9bd6355f239a13f25 100644 (file)
--- a/testsuite/ccm-test.c
+++ b/testsuite/ccm-test.c
@@ -156,10 +156,12 @@ test_cipher_ccm(const struct nettle_cipher *cipher,
     memset(de_digest, 0, sizeof(de_digest));
 
     ccm_encrypt_message(ctx, cipher->encrypt, nonce->length, nonce->data,
-                       authdata->length, authdata->data, tlength, ciphertext->length, en_data, cleartext->data);
+                       authdata->length, authdata->data, tlength,
+                       ciphertext->length, en_data, cleartext->data);
 
     ret = ccm_decrypt_message(ctx, cipher->encrypt, nonce->length, nonce->data,
-                             authdata->length, authdata->data, tlength, ciphertext->length, de_data, ciphertext->data);
+                             authdata->length, authdata->data, tlength,
+                             cleartext->length, de_data, ciphertext->data);
 
     if (ret != 1) fprintf(stderr, "ccm_decrypt_message failed to validate message\n");
     test_compare_results("CCM_MSG", authdata,
@@ -169,13 +171,15 @@ test_cipher_ccm(const struct nettle_cipher *cipher,
     if (tlength) {
       en_data[0] ^= 1;
       ret = ccm_decrypt_message(ctx, cipher->encrypt, nonce->length, nonce->data,
-                               authdata->length, authdata->data, tlength, ciphertext->length, de_data, en_data);
+                               authdata->length, authdata->data, tlength,
+                               cleartext->length, de_data, en_data);
       if (ret != 0) fprintf(stderr, "ccm_decrypt_message failed to detect corrupted message\n");
     }
     /* Ensure we can detect corrupted adata. */
     if (tlength && authdata->length) {
       ret = ccm_decrypt_message(ctx, cipher->encrypt, nonce->length, nonce->data,
-                               authdata->length-1, authdata->data, tlength, ciphertext->length, de_data, ciphertext->data);
+                               authdata->length-1, authdata->data, tlength,
+                               cleartext->length, de_data, ciphertext->data);
       if (ret != 0) fprintf(stderr, "ccm_decrypt_message failed to detect corrupted message\n");
     }
   }