Prefer AES-GCM when hardware support is available.
BUG=396787
Change-Id: I72ddb0ec3c71dbc70054403163930cbbde4b6009
Reviewed-on: https://boringssl-review.googlesource.com/1581
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/include/openssl/aead.h b/include/openssl/aead.h
index 7e4682c..6f66e9c 100644
--- a/include/openssl/aead.h
+++ b/include/openssl/aead.h
@@ -115,6 +115,10 @@
* See |EVP_aead_aes_128_key_wrap| for details. */
OPENSSL_EXPORT const EVP_AEAD *EVP_aead_aes_256_key_wrap();
+/* EVP_has_aes_hardware returns one if we enable hardware support for fast and
+ * constant-time AES-GCM. */
+OPENSSL_EXPORT int EVP_has_aes_hardware(void);
+
/* TLS specific AEAD algorithms.
*
diff --git a/include/openssl/cpu.h b/include/openssl/cpu.h
index bec157f..3cc1e5e 100644
--- a/include/openssl/cpu.h
+++ b/include/openssl/cpu.h
@@ -79,7 +79,10 @@
* Index 1:
* ECX for CPUID where EAX = 1
* Index 2:
- * EBX for CPUID where EAX = 7 */
+ * EBX for CPUID where EAX = 7
+ *
+ * Note: the CPUID bits are pre-adjusted for the OSXSAVE bit and the YMM and XMM
+ * bits in XCR0, so it is not necessary to check those. */
extern uint32_t OPENSSL_ia32cap_P[4];
#endif
