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-rw-r--r--third_party/abseil_cpp/absl/random/internal/seed_material.cc219
1 files changed, 0 insertions, 219 deletions
diff --git a/third_party/abseil_cpp/absl/random/internal/seed_material.cc b/third_party/abseil_cpp/absl/random/internal/seed_material.cc
deleted file mode 100644
index 4d38a57419ec..000000000000
--- a/third_party/abseil_cpp/absl/random/internal/seed_material.cc
+++ /dev/null
@@ -1,219 +0,0 @@
-// Copyright 2017 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include "absl/random/internal/seed_material.h"
-
-#include <fcntl.h>
-
-#ifndef _WIN32
-#include <unistd.h>
-#else
-#include <io.h>
-#endif
-
-#include <algorithm>
-#include <cerrno>
-#include <cstdint>
-#include <cstdlib>
-#include <cstring>
-
-#include "absl/base/internal/raw_logging.h"
-#include "absl/strings/ascii.h"
-#include "absl/strings/escaping.h"
-#include "absl/strings/string_view.h"
-#include "absl/strings/strip.h"
-
-#if defined(__native_client__)
-
-#include <nacl/nacl_random.h>
-#define ABSL_RANDOM_USE_NACL_SECURE_RANDOM 1
-
-#elif defined(_WIN32)
-
-#include <windows.h>
-#define ABSL_RANDOM_USE_BCRYPT 1
-#pragma comment(lib, "bcrypt.lib")
-
-#elif defined(__Fuchsia__)
-#include <zircon/syscalls.h>
-
-#endif
-
-#if defined(ABSL_RANDOM_USE_BCRYPT)
-#include <bcrypt.h>
-
-#ifndef BCRYPT_SUCCESS
-#define BCRYPT_SUCCESS(Status) (((NTSTATUS)(Status)) >= 0)
-#endif
-// Also link bcrypt; this can be done via linker options or:
-// #pragma comment(lib, "bcrypt.lib")
-#endif
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace random_internal {
-namespace {
-
-// Read OS Entropy for random number seeds.
-// TODO(absl-team): Possibly place a cap on how much entropy may be read at a
-// time.
-
-#if defined(ABSL_RANDOM_USE_BCRYPT)
-
-// On Windows potentially use the BCRYPT CNG API to read available entropy.
-bool ReadSeedMaterialFromOSEntropyImpl(absl::Span<uint32_t> values) {
-  BCRYPT_ALG_HANDLE hProvider;
-  NTSTATUS ret;
-  ret = BCryptOpenAlgorithmProvider(&hProvider, BCRYPT_RNG_ALGORITHM,
-                                    MS_PRIMITIVE_PROVIDER, 0);
-  if (!(BCRYPT_SUCCESS(ret))) {
-    ABSL_RAW_LOG(ERROR, "Failed to open crypto provider.");
-    return false;
-  }
-  ret = BCryptGenRandom(
-      hProvider,                                             // provider
-      reinterpret_cast<UCHAR*>(values.data()),               // buffer
-      static_cast<ULONG>(sizeof(uint32_t) * values.size()),  // bytes
-      0);                                                    // flags
-  BCryptCloseAlgorithmProvider(hProvider, 0);
-  return BCRYPT_SUCCESS(ret);
-}
-
-#elif defined(ABSL_RANDOM_USE_NACL_SECURE_RANDOM)
-
-// On NaCL use nacl_secure_random to acquire bytes.
-bool ReadSeedMaterialFromOSEntropyImpl(absl::Span<uint32_t> values) {
-  auto buffer = reinterpret_cast<uint8_t*>(values.data());
-  size_t buffer_size = sizeof(uint32_t) * values.size();
-
-  uint8_t* output_ptr = buffer;
-  while (buffer_size > 0) {
-    size_t nread = 0;
-    const int error = nacl_secure_random(output_ptr, buffer_size, &nread);
-    if (error != 0 || nread > buffer_size) {
-      ABSL_RAW_LOG(ERROR, "Failed to read secure_random seed data: %d", error);
-      return false;
-    }
-    output_ptr += nread;
-    buffer_size -= nread;
-  }
-  return true;
-}
-
-#elif defined(__Fuchsia__)
-
-bool ReadSeedMaterialFromOSEntropyImpl(absl::Span<uint32_t> values) {
-  auto buffer = reinterpret_cast<uint8_t*>(values.data());
-  size_t buffer_size = sizeof(uint32_t) * values.size();
-  zx_cprng_draw(buffer, buffer_size);
-  return true;
-}
-
-#else
-
-// On *nix, read entropy from /dev/urandom.
-bool ReadSeedMaterialFromOSEntropyImpl(absl::Span<uint32_t> values) {
-  const char kEntropyFile[] = "/dev/urandom";
-
-  auto buffer = reinterpret_cast<uint8_t*>(values.data());
-  size_t buffer_size = sizeof(uint32_t) * values.size();
-
-  int dev_urandom = open(kEntropyFile, O_RDONLY);
-  bool success = (-1 != dev_urandom);
-  if (!success) {
-    return false;
-  }
-
-  while (success && buffer_size > 0) {
-    int bytes_read = read(dev_urandom, buffer, buffer_size);
-    int read_error = errno;
-    success = (bytes_read > 0);
-    if (success) {
-      buffer += bytes_read;
-      buffer_size -= bytes_read;
-    } else if (bytes_read == -1 && read_error == EINTR) {
-      success = true;  // Need to try again.
-    }
-  }
-  close(dev_urandom);
-  return success;
-}
-
-#endif
-
-}  // namespace
-
-bool ReadSeedMaterialFromOSEntropy(absl::Span<uint32_t> values) {
-  assert(values.data() != nullptr);
-  if (values.data() == nullptr) {
-    return false;
-  }
-  if (values.empty()) {
-    return true;
-  }
-  return ReadSeedMaterialFromOSEntropyImpl(values);
-}
-
-void MixIntoSeedMaterial(absl::Span<const uint32_t> sequence,
-                         absl::Span<uint32_t> seed_material) {
-  // Algorithm is based on code available at
-  // https://gist.github.com/imneme/540829265469e673d045
-  constexpr uint32_t kInitVal = 0x43b0d7e5;
-  constexpr uint32_t kHashMul = 0x931e8875;
-  constexpr uint32_t kMixMulL = 0xca01f9dd;
-  constexpr uint32_t kMixMulR = 0x4973f715;
-  constexpr uint32_t kShiftSize = sizeof(uint32_t) * 8 / 2;
-
-  uint32_t hash_const = kInitVal;
-  auto hash = [&](uint32_t value) {
-    value ^= hash_const;
-    hash_const *= kHashMul;
-    value *= hash_const;
-    value ^= value >> kShiftSize;
-    return value;
-  };
-
-  auto mix = [&](uint32_t x, uint32_t y) {
-    uint32_t result = kMixMulL * x - kMixMulR * y;
-    result ^= result >> kShiftSize;
-    return result;
-  };
-
-  for (const auto& seq_val : sequence) {
-    for (auto& elem : seed_material) {
-      elem = mix(elem, hash(seq_val));
-    }
-  }
-}
-
-absl::optional<uint32_t> GetSaltMaterial() {
-  // Salt must be common for all generators within the same process so read it
-  // only once and store in static variable.
-  static const auto salt_material = []() -> absl::optional<uint32_t> {
-    uint32_t salt_value = 0;
-
-    if (random_internal::ReadSeedMaterialFromOSEntropy(
-            MakeSpan(&salt_value, 1))) {
-      return salt_value;
-    }
-
-    return absl::nullopt;
-  }();
-
-  return salt_material;
-}
-
-}  // namespace random_internal
-ABSL_NAMESPACE_END
-}  // namespace absl