Move ARM cpuinfo functions to the header.

ClusterFuzz folks want to switch to a shared library build, so call into
these another way. The new setup isn't quite ideal because the real code
builds as C and now tests as C++, but it should work.

Bug: chromium:907115
Change-Id: Ia1ffc18832739b09fee21b84ee5d181e61feaa15
Reviewed-on: https://boringssl-review.googlesource.com/c/33285
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>

crypto/cpu-arm-linux.c

@@ -14,9 +14,6 @@
 
 #include <openssl/cpu.h>
 
-#include "cpu-arm-linux.h"
-#include "internal.h"
-
 #if defined(OPENSSL_ARM) && !defined(OPENSSL_STATIC_ARMCAP)
 #include <errno.h>
 #include <fcntl.h>
@@ -26,155 +23,8 @@
 #include <openssl/arm_arch.h>
 #include <openssl/buf.h>
 #include <openssl/mem.h>
-#endif
-
-
-// The following functions are only used in ARM, but they are defined on all
-// platforms for testing and fuzzing purposes.
-
-static int STRING_PIECE_equals(const STRING_PIECE *a, const char *b) {
-  size_t b_len = strlen(b);
-  return a->len == b_len && OPENSSL_memcmp(a->data, b, b_len) == 0;
-}
-
-// STRING_PIECE_split finds the first occurence of |sep| in |in| and, if found,
-// sets |*out_left| and |*out_right| to |in| split before and after it. It
-// returns one if |sep| was found and zero otherwise.
-static int STRING_PIECE_split(STRING_PIECE *out_left, STRING_PIECE *out_right,
-                              const STRING_PIECE *in, char sep) {
-  const char *p = OPENSSL_memchr(in->data, sep, in->len);
-  if (p == NULL) {
-    return 0;
-  }
-  // |out_left| or |out_right| may alias |in|, so make a copy.
-  STRING_PIECE in_copy = *in;
-  out_left->data = in_copy.data;
-  out_left->len = p - in_copy.data;
-  out_right->data = in_copy.data + out_left->len + 1;
-  out_right->len = in_copy.len - out_left->len - 1;
-  return 1;
-}
-
-// STRING_PIECE_get_delimited reads a |sep|-delimited entry from |s|, writing it
-// to |out| and updating |s| to point beyond it. It returns one on success and
-// zero if |s| is empty. If |s| is has no copies of |sep| and is non-empty, it
-// reads the entire string to |out|.
-static int STRING_PIECE_get_delimited(STRING_PIECE *s, STRING_PIECE *out, char sep) {
-  if (s->len == 0) {
-    return 0;
-  }
-  if (!STRING_PIECE_split(out, s, s, sep)) {
-    // |s| had no instances of |sep|. Return the entire string.
-    *out = *s;
-    s->data += s->len;
-    s->len = 0;
-  }
-  return 1;
-}
-
-// STRING_PIECE_trim removes leading and trailing whitespace from |s|.
-static void STRING_PIECE_trim(STRING_PIECE *s) {
-  while (s->len != 0 && (s->data[0] == ' ' || s->data[0] == '\t')) {
-    s->data++;
-    s->len--;
-  }
-  while (s->len != 0 &&
-         (s->data[s->len - 1] == ' ' || s->data[s->len - 1] == '\t')) {
-    s->len--;
-  }
-}
-
-// extract_cpuinfo_field extracts a /proc/cpuinfo field named |field| from
-// |in|. If found, it sets |*out| to the value and returns one. Otherwise, it
-// returns zero.
-static int extract_cpuinfo_field(STRING_PIECE *out, const STRING_PIECE *in,
-                                 const char *field) {
-  // Process |in| one line at a time.
-  STRING_PIECE remaining = *in, line;
-  while (STRING_PIECE_get_delimited(&remaining, &line, '\n')) {
-    STRING_PIECE key, value;
-    if (!STRING_PIECE_split(&key, &value, &line, ':')) {
-      continue;
-    }
-    STRING_PIECE_trim(&key);
-    if (STRING_PIECE_equals(&key, field)) {
-      STRING_PIECE_trim(&value);
-      *out = value;
-      return 1;
-    }
-  }
-
-  return 0;
-}
 
-static int cpuinfo_field_equals(const STRING_PIECE *cpuinfo, const char *field,
-                                const char *value) {
-  STRING_PIECE extracted;
-  return extract_cpuinfo_field(&extracted, cpuinfo, field) &&
-         STRING_PIECE_equals(&extracted, value);
-}
-
-// has_list_item treats |list| as a space-separated list of items and returns
-// one if |item| is contained in |list| and zero otherwise.
-static int has_list_item(const STRING_PIECE *list, const char *item) {
-  STRING_PIECE remaining = *list, feature;
-  while (STRING_PIECE_get_delimited(&remaining, &feature, ' ')) {
-    if (STRING_PIECE_equals(&feature, item)) {
-      return 1;
-    }
-  }
-  return 0;
-}
-
-unsigned long crypto_get_arm_hwcap_from_cpuinfo(const STRING_PIECE *cpuinfo) {
-  if (cpuinfo_field_equals(cpuinfo, "CPU architecture", "8")) {
-    // This is a 32-bit ARM binary running on a 64-bit kernel. NEON is always
-    // available on ARMv8. Linux omits required features, so reading the
-    // "Features" line does not work. (For simplicity, use strict equality. We
-    // assume everything running on future ARM architectures will have a
-    // working |getauxval|.)
-    return HWCAP_NEON;
-  }
-
-  STRING_PIECE features;
-  if (extract_cpuinfo_field(&features, cpuinfo, "Features") &&
-      has_list_item(&features, "neon")) {
-    return HWCAP_NEON;
-  }
-  return 0;
-}
-
-unsigned long crypto_get_arm_hwcap2_from_cpuinfo(const STRING_PIECE *cpuinfo) {
-  STRING_PIECE features;
-  if (!extract_cpuinfo_field(&features, cpuinfo, "Features")) {
-    return 0;
-  }
-
-  unsigned long ret = 0;
-  if (has_list_item(&features, "aes")) {
-    ret |= HWCAP2_AES;
-  }
-  if (has_list_item(&features, "pmull")) {
-    ret |= HWCAP2_PMULL;
-  }
-  if (has_list_item(&features, "sha1")) {
-    ret |= HWCAP2_SHA1;
-  }
-  if (has_list_item(&features, "sha2")) {
-    ret |= HWCAP2_SHA2;
-  }
-  return ret;
-}
-
-int crypto_cpuinfo_has_broken_neon(const STRING_PIECE *cpuinfo) {
-  return cpuinfo_field_equals(cpuinfo, "CPU implementer", "0x51") &&
-         cpuinfo_field_equals(cpuinfo, "CPU architecture", "7") &&
-         cpuinfo_field_equals(cpuinfo, "CPU variant", "0x1") &&
-         cpuinfo_field_equals(cpuinfo, "CPU part", "0x04d") &&
-         cpuinfo_field_equals(cpuinfo, "CPU revision", "0");
-}
-
-#if defined(OPENSSL_ARM) && !defined(OPENSSL_STATIC_ARMCAP)
+#include "cpu-arm-linux.h"
 
 #define AT_HWCAP 16
 #define AT_HWCAP2 26

crypto/cpu-arm-linux.h

@@ -17,14 +17,17 @@
 
 #include <openssl/base.h>
 
+#include <string.h>
+
+#include "internal.h"
+
 #if defined(__cplusplus)
 extern "C" {
 #endif
 
 
-// The following symbols are defined on all platforms and exported for testing
-// and fuzzing purposes. They are not exported from the shared library so the
-// static linker will drop them outside of tests.
+// The cpuinfo parser lives in a header file so it may be accessible from
+// cross-platform fuzzers without adding code to those platforms normally.
 
 #define HWCAP_NEON (1 << 12)
 
@@ -40,17 +43,156 @@ typedef struct {
   size_t len;
 } STRING_PIECE;
 
+static int STRING_PIECE_equals(const STRING_PIECE *a, const char *b) {
+  size_t b_len = strlen(b);
+  return a->len == b_len && OPENSSL_memcmp(a->data, b, b_len) == 0;
+}
+
+// STRING_PIECE_split finds the first occurence of |sep| in |in| and, if found,
+// sets |*out_left| and |*out_right| to |in| split before and after it. It
+// returns one if |sep| was found and zero otherwise.
+static int STRING_PIECE_split(STRING_PIECE *out_left, STRING_PIECE *out_right,
+                              const STRING_PIECE *in, char sep) {
+  const char *p = (const char *)OPENSSL_memchr(in->data, sep, in->len);
+  if (p == NULL) {
+    return 0;
+  }
+  // |out_left| or |out_right| may alias |in|, so make a copy.
+  STRING_PIECE in_copy = *in;
+  out_left->data = in_copy.data;
+  out_left->len = p - in_copy.data;
+  out_right->data = in_copy.data + out_left->len + 1;
+  out_right->len = in_copy.len - out_left->len - 1;
+  return 1;
+}
+
+// STRING_PIECE_get_delimited reads a |sep|-delimited entry from |s|, writing it
+// to |out| and updating |s| to point beyond it. It returns one on success and
+// zero if |s| is empty. If |s| is has no copies of |sep| and is non-empty, it
+// reads the entire string to |out|.
+static int STRING_PIECE_get_delimited(STRING_PIECE *s, STRING_PIECE *out, char sep) {
+  if (s->len == 0) {
+    return 0;
+  }
+  if (!STRING_PIECE_split(out, s, s, sep)) {
+    // |s| had no instances of |sep|. Return the entire string.
+    *out = *s;
+    s->data += s->len;
+    s->len = 0;
+  }
+  return 1;
+}
+
+// STRING_PIECE_trim removes leading and trailing whitespace from |s|.
+static void STRING_PIECE_trim(STRING_PIECE *s) {
+  while (s->len != 0 && (s->data[0] == ' ' || s->data[0] == '\t')) {
+    s->data++;
+    s->len--;
+  }
+  while (s->len != 0 &&
+         (s->data[s->len - 1] == ' ' || s->data[s->len - 1] == '\t')) {
+    s->len--;
+  }
+}
+
+// extract_cpuinfo_field extracts a /proc/cpuinfo field named |field| from
+// |in|. If found, it sets |*out| to the value and returns one. Otherwise, it
+// returns zero.
+static int extract_cpuinfo_field(STRING_PIECE *out, const STRING_PIECE *in,
+                                 const char *field) {
+  // Process |in| one line at a time.
+  STRING_PIECE remaining = *in, line;
+  while (STRING_PIECE_get_delimited(&remaining, &line, '\n')) {
+    STRING_PIECE key, value;
+    if (!STRING_PIECE_split(&key, &value, &line, ':')) {
+      continue;
+    }
+    STRING_PIECE_trim(&key);
+    if (STRING_PIECE_equals(&key, field)) {
+      STRING_PIECE_trim(&value);
+      *out = value;
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+static int cpuinfo_field_equals(const STRING_PIECE *cpuinfo, const char *field,
+                                const char *value) {
+  STRING_PIECE extracted;
+  return extract_cpuinfo_field(&extracted, cpuinfo, field) &&
+         STRING_PIECE_equals(&extracted, value);
+}
+
+// has_list_item treats |list| as a space-separated list of items and returns
+// one if |item| is contained in |list| and zero otherwise.
+static int has_list_item(const STRING_PIECE *list, const char *item) {
+  STRING_PIECE remaining = *list, feature;
+  while (STRING_PIECE_get_delimited(&remaining, &feature, ' ')) {
+    if (STRING_PIECE_equals(&feature, item)) {
+      return 1;
+    }
+  }
+  return 0;
+}
+
 // crypto_get_arm_hwcap_from_cpuinfo returns an equivalent ARM |AT_HWCAP| value
 // from |cpuinfo|.
-unsigned long crypto_get_arm_hwcap_from_cpuinfo(const STRING_PIECE *cpuinfo);
+static unsigned long crypto_get_arm_hwcap_from_cpuinfo(
+    const STRING_PIECE *cpuinfo) {
+  if (cpuinfo_field_equals(cpuinfo, "CPU architecture", "8")) {
+    // This is a 32-bit ARM binary running on a 64-bit kernel. NEON is always
+    // available on ARMv8. Linux omits required features, so reading the
+    // "Features" line does not work. (For simplicity, use strict equality. We
+    // assume everything running on future ARM architectures will have a
+    // working |getauxval|.)
+    return HWCAP_NEON;
+  }
+
+  STRING_PIECE features;
+  if (extract_cpuinfo_field(&features, cpuinfo, "Features") &&
+      has_list_item(&features, "neon")) {
+    return HWCAP_NEON;
+  }
+  return 0;
+}
 
 // crypto_get_arm_hwcap2_from_cpuinfo returns an equivalent ARM |AT_HWCAP2|
 // value from |cpuinfo|.
-unsigned long crypto_get_arm_hwcap2_from_cpuinfo(const STRING_PIECE *cpuinfo);
+static unsigned long crypto_get_arm_hwcap2_from_cpuinfo(
+    const STRING_PIECE *cpuinfo) {
+  STRING_PIECE features;
+  if (!extract_cpuinfo_field(&features, cpuinfo, "Features")) {
+    return 0;
+  }
+
+  unsigned long ret = 0;
+  if (has_list_item(&features, "aes")) {
+    ret |= HWCAP2_AES;
+  }
+  if (has_list_item(&features, "pmull")) {
+    ret |= HWCAP2_PMULL;
+  }
+  if (has_list_item(&features, "sha1")) {
+    ret |= HWCAP2_SHA1;
+  }
+  if (has_list_item(&features, "sha2")) {
+    ret |= HWCAP2_SHA2;
+  }
+  return ret;
+}
 
 // crypto_cpuinfo_has_broken_neon returns one if |cpuinfo| matches a CPU known
 // to have broken NEON unit and zero otherwise. See https://crbug.com/341598.
-int crypto_cpuinfo_has_broken_neon(const STRING_PIECE *cpuinfo);
+static int crypto_cpuinfo_has_broken_neon(const STRING_PIECE *cpuinfo) {
+  return cpuinfo_field_equals(cpuinfo, "CPU implementer", "0x51") &&
+         cpuinfo_field_equals(cpuinfo, "CPU architecture", "7") &&
+         cpuinfo_field_equals(cpuinfo, "CPU variant", "0x1") &&
+         cpuinfo_field_equals(cpuinfo, "CPU part", "0x04d") &&
+         cpuinfo_field_equals(cpuinfo, "CPU revision", "0");
+}
+
 
 #if defined(__cplusplus)
 }  // extern C

crypto/cpu-arm-linux_test.cc

@@ -19,8 +19,6 @@
 #include <gtest/gtest.h>
 
 
-#if !defined(BORINGSSL_SHARED_LIBRARY)
-
 TEST(ARMLinuxTest, CPUInfo) {
   struct CPUInfoTest {
     const char *cpuinfo;
@@ -232,5 +230,3 @@ TEST(ARMLinuxTest, CPUInfo) {
     EXPECT_EQ(t.broken_neon ? 1 : 0, crypto_cpuinfo_has_broken_neon(&sp));
   }
 }
-
-#endif  // !BORINGSSL_SHARED_LIBRARY