Add cpu-aarch64-fuchsia.c

Fuchsia/Zircon recently added support for exposing arm64 CPU features;
this CL uses the new system call to set OPENSSL_armcap_P.

Change-Id: I045dc0b58117afe6dae315a82bf9acfd8d99be1a
Reviewed-on: https://boringssl-review.googlesource.com/25865
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

PORTING.md

@@ -210,7 +210,7 @@ strings and loading algorithms, etc. All of these functions still exist in
 BoringSSL for convenience, but they do nothing and are not necessary.
 
 The one exception is `CRYPTO_library_init`. In `BORINGSSL_NO_STATIC_INITIALIZER`
-builds, it must be called to query CPU capabitilies before the rest of the
+builds, it must be called to query CPU capabilities before the rest of the
 library. In the default configuration, this is done with a static initializer
 and is also unnecessary.
 

crypto/CMakeLists.txt

@@ -134,6 +134,7 @@ add_library(
 
   OBJECT
 
+  cpu-aarch64-fuchsia.c
   cpu-aarch64-linux.c
   cpu-arm.c
   cpu-arm-linux.c

crypto/cpu-aarch64-fuchsia.c

@@ -0,0 +1,55 @@
+/* Copyright (c) 2018, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <openssl/cpu.h>
+
+#if defined(OPENSSL_AARCH64) && defined(OPENSSL_FUCHSIA) && \
+    !defined(OPENSSL_STATIC_ARMCAP)
+
+#include <zircon/features.h>
+#include <zircon/syscalls.h>
+#include <zircon/types.h>
+
+#include <openssl/arm_arch.h>
+
+#include "internal.h"
+
+extern uint32_t OPENSSL_armcap_P;
+
+void OPENSSL_cpuid_setup(void) {
+  uint32_t hwcap;
+  zx_status_t rc = zx_system_get_features(ZX_FEATURE_KIND_CPU, &hwcap);
+  if (rc != ZX_OK || (hwcap & ZX_ARM64_FEATURE_ISA_ASIMD) == 0) {
+    // Matching OpenSSL, if NEON/ASIMD is missing, don't report other features
+    // either.
+    return;
+  }
+
+  OPENSSL_armcap_P |= ARMV7_NEON;
+
+  if (hwcap & ZX_ARM64_FEATURE_ISA_AES) {
+    OPENSSL_armcap_P |= ARMV8_AES;
+  }
+  if (hwcap & ZX_ARM64_FEATURE_ISA_PMULL) {
+    OPENSSL_armcap_P |= ARMV8_PMULL;
+  }
+  if (hwcap & ZX_ARM64_FEATURE_ISA_SHA1) {
+    OPENSSL_armcap_P |= ARMV8_SHA1;
+  }
+  if (hwcap & ZX_ARM64_FEATURE_ISA_SHA2) {
+    OPENSSL_armcap_P |= ARMV8_SHA256;
+  }
+}
+
+#endif  // OPENSSL_AARCH64 && !OPENSSL_STATIC_ARMCAP

crypto/cpu-aarch64-linux.c

@@ -14,7 +14,8 @@
 
 #include <openssl/cpu.h>
 
-#if defined(OPENSSL_AARCH64) && !defined(OPENSSL_STATIC_ARMCAP)
+#if defined(OPENSSL_AARCH64) && defined(OPENSSL_LINUX) && \
+    !defined(OPENSSL_STATIC_ARMCAP)
 
 #include <sys/auxv.h>