aes: Adapt AES code to build for EC

Update header, C code, and tweak the assembly for ARMv7-M.

Rename aes_now_* functions to AES_* to avoid the need for a
separate wrapper.

Also add a test with FIPS-197 test vectors, and speed test.

BRANCH=none
BUG=b:111160949
TEST=make run-aes -j
TEST=make BOARD=nocturne_fp test-aes -j
     flash_fp_mcu aes.bin
     runtest => pass
     (C implementation speed: 11977 us for 1000 iterations)
     (ASM implementation speed: 5815 us for 1000 iterations)

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>

Change-Id: I2048aae73decccb893bc1724b2617b0b902dd992
Reviewed-on: https://chromium-review.googlesource.com/1120340
Commit-Ready: Nicolas Boichat <drinkcat@chromium.org>
Tested-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Adam Langley <agl@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>

1 files changed, 66 insertions, 107 deletions

diff --git a/third_party/boringssl/include/aes.h b/third_party/boringssl/include/aes.h
index 115658542f..6418a350eb 100644
--- a/third_party/boringssl/include/aes.h
+++ b/third_party/boringssl/include/aes.h
@@ -46,125 +46,84 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  * ==================================================================== */
 
-#ifndef OPENSSL_HEADER_AES_H
-#define OPENSSL_HEADER_AES_H
-
-#include <openssl/base.h>
-
-#if defined(__cplusplus)
-extern "C" {
-#endif
-
-
-// Raw AES functions.
+#ifndef __CROS_EC_AES_H
+#define __CROS_EC_AES_H
 
+#include <stdint.h>
 
 #define AES_ENCRYPT 1
 #define AES_DECRYPT 0
 
-// AES_MAXNR is the maximum number of AES rounds.
+/* AES_MAXNR is the maximum number of AES rounds. */
 #define AES_MAXNR 14
 
 #define AES_BLOCK_SIZE 16
 
-// aes_key_st should be an opaque type, but EVP requires that the size be
-// known.
+/*
+ * aes_key_st should be an opaque type, but EVP requires that the size be
+ * known.
+ */
 struct aes_key_st {
   uint32_t rd_key[4 * (AES_MAXNR + 1)];
   unsigned rounds;
 };
 typedef struct aes_key_st AES_KEY;
 
-// AES_set_encrypt_key configures |aeskey| to encrypt with the |bits|-bit key,
-// |key|.
-//
-// WARNING: unlike other OpenSSL functions, this returns zero on success and a
-// negative number on error.
-OPENSSL_EXPORT int AES_set_encrypt_key(const uint8_t *key, unsigned bits,
-                                       AES_KEY *aeskey);
-
-// AES_set_decrypt_key configures |aeskey| to decrypt with the |bits|-bit key,
-// |key|.
-//
-// WARNING: unlike other OpenSSL functions, this returns zero on success and a
-// negative number on error.
-OPENSSL_EXPORT int AES_set_decrypt_key(const uint8_t *key, unsigned bits,
-                                       AES_KEY *aeskey);
-
-// AES_encrypt encrypts a single block from |in| to |out| with |key|. The |in|
-// and |out| pointers may overlap.
-OPENSSL_EXPORT void AES_encrypt(const uint8_t *in, uint8_t *out,
-                                const AES_KEY *key);
-
-// AES_decrypt decrypts a single block from |in| to |out| with |key|. The |in|
-// and |out| pointers may overlap.
-OPENSSL_EXPORT void AES_decrypt(const uint8_t *in, uint8_t *out,
-                                const AES_KEY *key);
-
-
-// Block cipher modes.
-
-// AES_ctr128_encrypt encrypts (or decrypts, it's the same in CTR mode) |len|
-// bytes from |in| to |out|. The |num| parameter must be set to zero on the
-// first call and |ivec| will be incremented.
-OPENSSL_EXPORT void AES_ctr128_encrypt(const uint8_t *in, uint8_t *out,
-                                       size_t len, const AES_KEY *key,
-                                       uint8_t ivec[AES_BLOCK_SIZE],
-                                       uint8_t ecount_buf[AES_BLOCK_SIZE],
-                                       unsigned int *num);
-
-// AES_ecb_encrypt encrypts (or decrypts, if |enc| == |AES_DECRYPT|) a single,
-// 16 byte block from |in| to |out|.
-OPENSSL_EXPORT void AES_ecb_encrypt(const uint8_t *in, uint8_t *out,
-                                    const AES_KEY *key, const int enc);
-
-// AES_cbc_encrypt encrypts (or decrypts, if |enc| == |AES_DECRYPT|) |len|
-// bytes from |in| to |out|. The length must be a multiple of the block size.
-OPENSSL_EXPORT void AES_cbc_encrypt(const uint8_t *in, uint8_t *out, size_t len,
-                                    const AES_KEY *key, uint8_t *ivec,
-                                    const int enc);
-
-// AES_ofb128_encrypt encrypts (or decrypts, it's the same in OFB mode) |len|
-// bytes from |in| to |out|. The |num| parameter must be set to zero on the
-// first call.
-OPENSSL_EXPORT void AES_ofb128_encrypt(const uint8_t *in, uint8_t *out,
-                                       size_t len, const AES_KEY *key,
-                                       uint8_t *ivec, int *num);
-
-// AES_cfb128_encrypt encrypts (or decrypts, if |enc| == |AES_DECRYPT|) |len|
-// bytes from |in| to |out|. The |num| parameter must be set to zero on the
-// first call.
-OPENSSL_EXPORT void AES_cfb128_encrypt(const uint8_t *in, uint8_t *out,
-                                       size_t len, const AES_KEY *key,
-                                       uint8_t *ivec, int *num, int enc);
-
-
-// AES key wrap.
-//
-// These functions implement AES Key Wrap mode, as defined in RFC 3394. They
-// should never be used except to interoperate with existing systems that use
-// this mode.
-
-// AES_wrap_key performs AES key wrap on |in| which must be a multiple of 8
-// bytes. |iv| must point to an 8 byte value or be NULL to use the default IV.
-// |key| must have been configured for encryption. On success, it writes
-// |in_len| + 8 bytes to |out| and returns |in_len| + 8. Otherwise, it returns
-// -1.
-OPENSSL_EXPORT int AES_wrap_key(const AES_KEY *key, const uint8_t *iv,
-                                uint8_t *out, const uint8_t *in, size_t in_len);
-
-// AES_unwrap_key performs AES key unwrap on |in| which must be a multiple of 8
-// bytes. |iv| must point to an 8 byte value or be NULL to use the default IV.
-// |key| must have been configured for decryption. On success, it writes
-// |in_len| - 8 bytes to |out| and returns |in_len| - 8. Otherwise, it returns
-// -1.
-OPENSSL_EXPORT int AES_unwrap_key(const AES_KEY *key, const uint8_t *iv,
-                                  uint8_t *out, const uint8_t *in,
-                                  size_t in_len);
-
-
-#if defined(__cplusplus)
-}  // extern C
-#endif
-
-#endif  // OPENSSL_HEADER_AES_H
+/*
+ * These functions are provided by either common/aes.c, or assembly code,
+ * and should not be called directly.
+ */
+void aes_nohw_encrypt(const uint8_t *in, uint8_t *out, const AES_KEY *key);
+void aes_nohw_decrypt(const uint8_t *in, uint8_t *out, const AES_KEY *key);
+int aes_nohw_set_encrypt_key(const uint8_t *key, unsigned bits,
+                             AES_KEY *aeskey);
+int aes_nohw_set_decrypt_key(const uint8_t *key, unsigned bits,
+                             AES_KEY *aeskey);
+
+/**
+ * AES_set_encrypt_key configures |aeskey| to encrypt with the |bits|-bit key,
+ * |key|.
+ *
+ * WARNING: unlike other OpenSSL functions, this returns zero on success and a
+ * negative number on error.
+ */
+static inline int AES_set_encrypt_key(const uint8_t *key, unsigned int bits,
+				      AES_KEY *aeskey)
+{
+	return aes_nohw_set_encrypt_key(key, bits, aeskey);
+}
+
+/**
+ * AES_set_decrypt_key configures |aeskey| to decrypt with the |bits|-bit key,
+ * |key|.
+ *
+ * WARNING: unlike other OpenSSL functions, this returns zero on success and a
+ * negative number on error.
+ */
+static inline int AES_set_decrypt_key(const uint8_t *key, unsigned int bits,
+				      AES_KEY *aeskey)
+{
+	return aes_nohw_set_decrypt_key(key, bits, aeskey);
+}
+
+/**
+ * AES_encrypt encrypts a single block from |in| to |out| with |key|. The |in|
+ * and |out| pointers may overlap.
+ */
+static inline void AES_encrypt(const uint8_t *in, uint8_t *out,
+			       const AES_KEY *key)
+{
+	aes_nohw_encrypt(in, out, key);
+}
+
+/**
+ * AES_decrypt decrypts a single block from |in| to |out| with |key|. The |in|
+ * and |out| pointers may overlap.
+ */
+static inline void AES_decrypt(const uint8_t *in, uint8_t *out,
+			const AES_KEY *key)
+{
+	aes_nohw_decrypt(in, out, key);
+}
+
+#endif  /* __CROS_EC_AES_H */