Add support for AES256 and AES192

(This will be used by prop224)

src/common/aes.c

@@ -48,7 +48,7 @@ ENABLE_GCC_WARNING(redundant-decls)
 
 /* We have five strategies for implementing AES counter mode.
  *
- * Best with x86 and x86_64: Use EVP_aes_ctr128() and EVP_EncryptUpdate().
+ * Best with x86 and x86_64: Use EVP_aes_*_ctr() and EVP_EncryptUpdate().
  * This is possible with OpenSSL 1.0.1, where the counter-mode implementation
  * can use bit-sliced or vectorized AES or AESNI as appropriate.
  *

src/common/crypto.c

@@ -541,6 +541,20 @@ crypto_pk_free(crypto_pk_t *env)
   tor_free(env);
 }
 
+/** Allocate and return a new symmetric cipher using the provided key and iv.
+ * The key is <b>bits</b> bits long; the IV is CIPHER_IV_LEN bytes.  Both
+ * must be provided. Key length must be 128, 192, or 256 */
+crypto_cipher_t *
+crypto_cipher_new_with_iv_and_bits(const uint8_t *key,
+                                   const uint8_t *iv,
+                                   int bits)
+{
+  tor_assert(key);
+  tor_assert(iv);
+
+  return aes_new_cipher((const uint8_t*)key, (const uint8_t*)iv, bits);
+}
+
 /** Allocate and return a new symmetric cipher using the provided key and iv.
  * The key is CIPHER_KEY_LEN bytes; the IV is CIPHER_IV_LEN bytes.  Both
  * must be provided.
@@ -548,23 +562,28 @@ crypto_pk_free(crypto_pk_t *env)
 crypto_cipher_t *
 crypto_cipher_new_with_iv(const char *key, const char *iv)
 {
-  crypto_cipher_t *env;
-  tor_assert(key);
-  tor_assert(iv);
-
-  env = aes_new_cipher((const uint8_t*)key, (const uint8_t*)iv, 128);
-
-  return env;
+  return crypto_cipher_new_with_iv_and_bits((uint8_t*)key, (uint8_t*)iv,
+                                            128);
 }
 
 /** Return a new crypto_cipher_t with the provided <b>key</b> and an IV of all
- * zero bytes.  */
+ * zero bytes and key length <b>bits</b>.  Key length must be 128, 192, or
+ * 256. */
 crypto_cipher_t *
-crypto_cipher_new(const char *key)
+crypto_cipher_new_with_bits(const char *key, int bits)
 {
   char zeroiv[CIPHER_IV_LEN];
   memset(zeroiv, 0, sizeof(zeroiv));
-  return crypto_cipher_new_with_iv(key, zeroiv);
+  return crypto_cipher_new_with_iv_and_bits((uint8_t*)key, (uint8_t*)zeroiv,
+                                            bits);
+}
+
+/** Return a new crypto_cipher_t with the provided <b>key</b> (of
+ * CIPHER_KEY_LEN bytes) and an IV of all zero bytes.  */
+crypto_cipher_t *
+crypto_cipher_new(const char *key)
+{
+  return crypto_cipher_new_with_bits(key, 128);
 }
 
 /** Free a symmetric cipher.

src/common/crypto.h

@@ -138,7 +138,11 @@ void crypto_pk_free(crypto_pk_t *env);
 
 void crypto_set_tls_dh_prime(void);
 crypto_cipher_t *crypto_cipher_new(const char *key);
+crypto_cipher_t *crypto_cipher_new_with_bits(const char *key, int bits);
 crypto_cipher_t *crypto_cipher_new_with_iv(const char *key, const char *iv);
+crypto_cipher_t *crypto_cipher_new_with_iv_and_bits(const uint8_t *key,
+                                                    const uint8_t *iv,
+                                                    int bits);
 void crypto_cipher_free(crypto_cipher_t *env);
 
 /* public key crypto */

src/test/test_crypto.c

@@ -363,9 +363,9 @@ test_crypto_rng_engine(void *arg)
   ;
 }
 
-/** Run unit tests for our AES functionality */
+/** Run unit tests for our AES128 functionality */
 static void
-test_crypto_aes(void *arg)
+test_crypto_aes128(void *arg)
 {
   char *data1 = NULL, *data2 = NULL, *data3 = NULL;
   crypto_cipher_t *env1 = NULL, *env2 = NULL;
@@ -514,32 +514,61 @@ test_crypto_aes(void *arg)
 static void
 test_crypto_aes_ctr_testvec(void *arg)
 {
-  (void)arg;
+  const char *bitstr = arg;
   char *mem_op_hex_tmp=NULL;
+  crypto_cipher_t *c=NULL;
 
   /* from NIST SP800-38a, section F.5 */
-  const char key16[] = "2b7e151628aed2a6abf7158809cf4f3c";
   const char ctr16[] = "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";
   const char plaintext16[] =
     "6bc1bee22e409f96e93d7e117393172a"
     "ae2d8a571e03ac9c9eb76fac45af8e51"
     "30c81c46a35ce411e5fbc1191a0a52ef"
     "f69f2445df4f9b17ad2b417be66c3710";
-  const char ciphertext16[] =
-    "874d6191b620e3261bef6864990db6ce"
-    "9806f66b7970fdff8617187bb9fffdff"
-    "5ae4df3edbd5d35e5b4f09020db03eab"
-    "1e031dda2fbe03d1792170a0f3009cee";
+  const char *ciphertext16;
+  const char *key16;
+  int bits;
 
-  char key[16];
+  if (!strcmp(bitstr, "128")) {
+    ciphertext16 = /* section F.5.1 */
+      "874d6191b620e3261bef6864990db6ce"
+      "9806f66b7970fdff8617187bb9fffdff"
+      "5ae4df3edbd5d35e5b4f09020db03eab"
+      "1e031dda2fbe03d1792170a0f3009cee";
+    key16 = "2b7e151628aed2a6abf7158809cf4f3c";
+    bits = 128;
+  } else if (!strcmp(bitstr, "192")) {
+    ciphertext16 = /* section F.5.3 */
+      "1abc932417521ca24f2b0459fe7e6e0b"
+      "090339ec0aa6faefd5ccc2c6f4ce8e94"
+      "1e36b26bd1ebc670d1bd1d665620abf7"
+      "4f78a7f6d29809585a97daec58c6b050";
+    key16 = "8e73b0f7da0e6452c810f32b809079e562f8ead2522c6b7b";
+    bits = 192;
+  } else if (!strcmp(bitstr, "256")) {
+    ciphertext16 = /* section F.5.5 */
+      "601ec313775789a5b7a7f504bbf3d228"
+      "f443e3ca4d62b59aca84e990cacaf5c5"
+      "2b0930daa23de94ce87017ba2d84988d"
+      "dfc9c58db67aada613c2dd08457941a6";
+    key16 =
+      "603deb1015ca71be2b73aef0857d7781"
+      "1f352c073b6108d72d9810a30914dff4";
+    bits = 256;
+  } else {
+    tt_abort_msg("AES doesn't support this number of bits.");
+  }
+
+  char key[32];
   char iv[16];
   char plaintext[16*4];
+  memset(key, 0xf9, sizeof(key)); /* poison extra bytes */
   base16_decode(key, sizeof(key), key16, strlen(key16));
   base16_decode(iv, sizeof(iv), ctr16, strlen(ctr16));
   base16_decode(plaintext, sizeof(plaintext),
                 plaintext16, strlen(plaintext16));
 
-  crypto_cipher_t *c = crypto_cipher_new_with_iv(key, iv);
+  c = crypto_cipher_new_with_iv_and_bits((uint8_t*)key, (uint8_t*)iv, bits);
   crypto_cipher_crypt_inplace(c, plaintext, sizeof(plaintext));
   test_memeq_hex(plaintext, ciphertext16);
 
@@ -2873,9 +2902,14 @@ struct testcase_t crypto_tests[] = {
   { "rng_strongest_broken", test_crypto_rng_strongest, TT_FORK,
     &passthrough_setup, (void*)"broken" },
   { "openssl_version", test_crypto_openssl_version, TT_FORK, NULL, NULL },
-  { "aes_AES", test_crypto_aes, TT_FORK, &passthrough_setup, (void*)"aes" },
-  { "aes_EVP", test_crypto_aes, TT_FORK, &passthrough_setup, (void*)"evp" },
-  { "aes_ctr_testvec", test_crypto_aes_ctr_testvec, 0, NULL, NULL },
+  { "aes_AES", test_crypto_aes128, TT_FORK, &passthrough_setup, (void*)"aes" },
+  { "aes_EVP", test_crypto_aes128, TT_FORK, &passthrough_setup, (void*)"evp" },
+  { "aes128_ctr_testvec", test_crypto_aes_ctr_testvec, 0,
+    &passthrough_setup, (void*)"128" },
+  { "aes192_ctr_testvec", test_crypto_aes_ctr_testvec, 0,
+    &passthrough_setup, (void*)"192" },
+  { "aes256_ctr_testvec", test_crypto_aes_ctr_testvec, 0,
+    &passthrough_setup, (void*)"256" },
   CRYPTO_LEGACY(sha),
   CRYPTO_LEGACY(pk),
   { "pk_fingerprints", test_crypto_pk_fingerprints, TT_FORK, NULL, NULL },