src: shift more crypto impl details to ncrypto

Author: jasnell

deps/ncrypto/ncrypto.cc

@@ -1,11 +1,11 @@
 #pragma once
 
+#include <cstddef>
 #include <list>
 #include <memory>
 #include <optional>
 #include <string>
 #include <string_view>
-#include <vector>
 #include "openssl/bn.h"
 #include <openssl/x509.h>
 #include <openssl/dh.h>
@@ -82,6 +82,15 @@ namespace ncrypto {
   void* operator new(size_t) = delete;                                         \
   void operator delete(void*) = delete;
 
+[[noreturn]] inline void unreachable() {
+#ifdef __GNUC__
+  __builtin_unreachable();
+#elif defined(_MSC_VER)
+  __assume(false);
+#else
+#endif
+}
+
 // ============================================================================
 // Error handling utilities
 
@@ -190,30 +199,91 @@ using SSLPointer = DeleteFnPtr<SSL, SSL_free>;
 using SSLSessionPointer = DeleteFnPtr<SSL_SESSION, SSL_SESSION_free>;
 using X509Pointer = DeleteFnPtr<X509, X509_free>;
 
+// An unowned, unmanaged pointer to a buffer of data.
+struct Buffer {
+  void* data;
+  size_t len;
+};
+
+// A managed pointer to a buffer of data. When destroyed the underlying
+// buffer will be freed.
+class DataPointer final {
+ public:
+  static DataPointer Alloc(size_t len);
+
+  DataPointer() = default;
+  explicit DataPointer(void* data, size_t len);
+  explicit DataPointer(const Buffer& buffer);
+  DataPointer(DataPointer&& other) noexcept;
+  DataPointer& operator=(DataPointer&& other) noexcept;
+  NCRYPTO_DISALLOW_COPY(DataPointer)
+  ~DataPointer();
+
+  inline bool operator==(std::nullptr_t) noexcept { return data_ == nullptr; }
+  inline operator bool() const { return data_ != nullptr; }
+  inline void* get() const noexcept { return data_; }
+  inline size_t size() const noexcept { return len_; }
+  void reset(void* data = nullptr, size_t len = 0);
+  void reset(const Buffer& buffer);
+
+  // Releases ownership of the underlying data buffer. It is the caller's
+  // responsibility to ensure the buffer is appropriately freed.
+  Buffer release();
+
+  // Returns a Buffer struct that is a view of the underlying data.
+  inline operator const Buffer() const {
+    return {
+      .data = data_,
+      .len = len_,
+    };
+  }
+
+ private:
+  void* data_ = nullptr;
+  size_t len_ = 0;
+};
+
 class BignumPointer final {
  public:
   BignumPointer() = default;
   explicit BignumPointer(BIGNUM* bignum);
+  explicit BignumPointer(const unsigned char* data, size_t len);
   BignumPointer(BignumPointer&& other) noexcept;
   BignumPointer& operator=(BignumPointer&& other) noexcept;
   NCRYPTO_DISALLOW_COPY(BignumPointer)
   ~BignumPointer();
 
-  bool operator==(const BignumPointer& other) noexcept;
-  bool operator==(const BIGNUM* other) noexcept;
-  inline bool operator==(std::nullptr_t) noexcept { return bn_ == nullptr; }
+  int operator<=>(const BignumPointer& other) const noexcept;
+  int operator<=>(const BIGNUM* other) const noexcept;
   inline operator bool() const { return bn_ != nullptr; }
   inline BIGNUM* get() const noexcept { return bn_.get(); }
   void reset(BIGNUM* bn = nullptr);
+  void reset(const unsigned char* data, size_t len);
   BIGNUM* release();
 
-  size_t byteLength();
+  bool isZero() const;
+  bool isOne() const;
+
+  bool setWord(unsigned long w);
+  unsigned long getWord() const;
+
+  size_t byteLength() const;
 
-  std::vector<uint8_t> encode();
-  std::vector<uint8_t> encodePadded(size_t size);
+  DataPointer toHex() const;
+  DataPointer encode() const;
+  DataPointer encodePadded(size_t size) const;
+  size_t encodeInto(unsigned char* out) const;
+  size_t encodePaddedInto(unsigned char* out, size_t size) const;
 
-  static std::vector<uint8_t> encode(const BIGNUM* bn);
-  static std::vector<uint8_t> encodePadded(const BIGNUM* bn, size_t size);
+  static BignumPointer New();
+  static BignumPointer NewSecure();
+  static DataPointer Encode(const BIGNUM* bn);
+  static DataPointer EncodePadded(const BIGNUM* bn, size_t size);
+  static size_t EncodePaddedInto(const BIGNUM* bn, unsigned char* out, size_t size);
+  static int GetBitCount(const BIGNUM* bn);
+  static int GetByteCount(const BIGNUM* bn);
+  static unsigned long GetWord(const BIGNUM* bn);
+  static const BIGNUM* One();
 
  private:
   DeleteFnPtr<BIGNUM, BN_clear_free> bn_;
@@ -269,11 +339,6 @@ bool testFipsEnabled();
 // ============================================================================
 // Various utilities
 
-struct Buffer {
-  const void* data;
-  size_t len;
-};
-
 bool CSPRNG(void* buffer, size_t length) NCRYPTO_MUST_USE_RESULT;
 
 // This callback is used to avoid the default passphrase callback in OpenSSL
@@ -285,6 +350,9 @@ int NoPasswordCallback(char* buf, int size, int rwflag, void* u);
 
 int PasswordCallback(char* buf, int size, int rwflag, void* u);
 
+bool SafeX509SubjectAltNamePrint(const BIOPointer& out, X509_EXTENSION* ext);
+bool SafeX509InfoAccessPrint(const BIOPointer& out, X509_EXTENSION* ext);
+
 // ============================================================================
 // Version metadata
 #define NCRYPTO_VERSION "0.0.1"

deps/ncrypto/ncrypto.h

@@ -185,10 +185,7 @@ BignumPointer GetCounter(const AESCipherConfig& params) {
 
   if (remainder == 0) {
     unsigned int byte_length = params.length / CHAR_BIT;
-    return BignumPointer(BN_bin2bn(
-        data + params.iv.size() - byte_length,
-        byte_length,
-        nullptr));
+    return BignumPointer(data + params.iv.size() - byte_length, byte_length);
   }
 
   unsigned int byte_length =
@@ -199,7 +196,7 @@ BignumPointer GetCounter(const AESCipherConfig& params) {
       data + params.iv.size());
   counter[0] &= ~(0xFF << remainder);
 
-  return BignumPointer(BN_bin2bn(counter.data(), counter.size(), nullptr));
+  return BignumPointer(counter.data(), counter.size());
 }
 
 std::vector<unsigned char> BlockWithZeroedCounter(
@@ -269,23 +266,22 @@ WebCryptoCipherStatus AES_CTR_Cipher(
     const AESCipherConfig& params,
     const ByteSource& in,
     ByteSource* out) {
-  BignumPointer num_counters(BN_new());
-  if (!BN_lshift(num_counters.get(), BN_value_one(), params.length))
+  auto num_counters = BignumPointer::New();
+  if (!BN_lshift(num_counters.get(), BignumPointer::One(), params.length))
     return WebCryptoCipherStatus::FAILED;
 
   BignumPointer current_counter = GetCounter(params);
 
-  BignumPointer num_output(BN_new());
+  auto num_output = BignumPointer::New();
 
-  if (!BN_set_word(num_output.get(), CeilDiv(in.size(), kAesBlockSize)))
+  if (!num_output.setWord(CeilDiv(in.size(), kAesBlockSize)))
     return WebCryptoCipherStatus::FAILED;
 
   // Just like in chromium's implementation, if the counter will
   // be incremented more than there are counter values, we fail.
-  if (BN_cmp(num_output.get(), num_counters.get()) > 0)
-    return WebCryptoCipherStatus::FAILED;
+  if (num_output > num_counters) return WebCryptoCipherStatus::FAILED;
 
-  BignumPointer remaining_until_reset(BN_new());
+  auto remaining_until_reset = BignumPointer::New();
   if (!BN_sub(remaining_until_reset.get(),
               num_counters.get(),
               current_counter.get())) {
@@ -298,7 +294,7 @@ WebCryptoCipherStatus AES_CTR_Cipher(
   // Also just like in chromium's implementation, if we can process
   // the input without wrapping the counter, we'll do it as a single
   // call here. If we can't, we'll fallback to the a two-step approach
-  if (BN_cmp(remaining_until_reset.get(), num_output.get()) >= 0) {
+  if (remaining_until_reset >= num_output) {
     auto status = AES_CTR_Cipher2(key_data,
                                   cipher_mode,
                                   params,
@@ -309,8 +305,7 @@ WebCryptoCipherStatus AES_CTR_Cipher(
     return status;
   }
 
-  BN_ULONG blocks_part1 = BN_get_word(remaining_until_reset.get());
-  BN_ULONG input_size_part1 = blocks_part1 * kAesBlockSize;
+  BN_ULONG input_size_part1 = remaining_until_reset.getWord() * kAesBlockSize;
 
   // Encrypt the first part...
   auto status =