Add a comment warning against using RSAPrivateKeyImport on untrusted sources.

base/crypto/rsa_private_key.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_CRYPTO_RSA_PRIVATE_KEY_H_
 #define BASE_CRYPTO_RSA_PRIVATE_KEY_H_
 
 #include "build/build_config.h"
 
 #if defined(USE_NSS)
@@ skipping 21 matching lines @@
 
   // ASN.1 encoding of the AlgorithmIdentifier from PKCS #8.
   static const uint8 kRsaAlgorithmIdentifier[];
 
   // ASN.1 tags for some types we use.
   static const uint8 kBitStringTag = 0x03;
   static const uint8 kIntegerTag = 0x02;
   static const uint8 kNullTag = 0x05;
   static const uint8 kOctetStringTag = 0x04;
   static const uint8 kSequenceTag = 0x30;
-  
+
   // |big_endian| here specifies the byte-significance of the integer components
   // that will be parsed & serialized (modulus(), etc...) during Import(),
   // Export() and ExportPublicKeyInfo() -- not the ASN.1 DER encoding of the
   // PrivateKeyInfo/PublicKeyInfo (which is always big-endian).
   explicit PrivateKeyInfoCodec(bool big_endian) : big_endian_(big_endian) {}
 
   // Exports the contents of the integer components to the ASN.1 DER encoding
   // of the PrivateKeyInfo structure to |output|.
   bool Export(std::vector<uint8>* output);
 
   // Exports the contents of the integer components to the ASN.1 DER encoding
   // of the PublicKeyInfo structure to |output|.
   bool ExportPublicKeyInfo(std::vector<uint8>* output);
 
   // Parses the ASN.1 DER encoding of the PrivateKeyInfo structure in |input|
   // and populates the integer components with |big_endian_| byte-significance.
+  // IMPORTANT NOTE: This is currently *not* security-approved for importing
+  // keys from unstrusted sources.
   bool Import(const std::vector<uint8>& input);
 
   // Accessors to the contents of the integer components of the PrivateKeyInfo
   // structure.
   std::vector<uint8>* modulus() { return &modulus_; };
   std::vector<uint8>* public_exponent() { return &public_exponent_; };
   std::vector<uint8>* private_exponent() { return &private_exponent_; };
   std::vector<uint8>* prime1() { return &prime1_; };
   std::vector<uint8>* prime2() { return &prime2_; };
   std::vector<uint8>* exponent1() { return &exponent1_; };
   std::vector<uint8>* exponent2() { return &exponent2_; };
   std::vector<uint8>* coefficient() { return &coefficient_; };
 
  private:
   // Utility wrappers for PrependIntegerImpl that use the class's |big_endian_|
   // value.
   void PrependInteger(const std::vector<uint8>& in, std::list<uint8>* out);
   void PrependInteger(uint8* val, int num_bytes, std::list<uint8>* data);
-  
+
   // Prepends the integer stored in |val| - |val + num_bytes| with |big_endian|
   // byte-significance into |data| as an ASN.1 integer.
   void PrependIntegerImpl(uint8* val,
                           int num_bytes,
                           std::list<uint8>* data,
                           bool big_endian);
 
   // Utility wrappers for ReadIntegerImpl that use the class's |big_endian_|
   // value.
   bool ReadInteger(uint8** pos, uint8* end, std::vector<uint8>* out);
   bool ReadIntegerWithExpectedSize(uint8** pos,
                                    uint8* end,
                                    size_t expected_size,
                                    std::vector<uint8>* out);
 
   // Reads an ASN.1 integer from |pos|, and stores the result into |out| with
   // |big_endian| byte-significance.
   bool ReadIntegerImpl(uint8** pos,
                        uint8* end,
-                       std::vector<uint8>* out, 
+                       std::vector<uint8>* out,
                        bool big_endian);
-  
+
   // Prepends the integer stored in |val|, starting a index |start|, for
   // |num_bytes| bytes onto |data|.
   void PrependBytes(uint8* val,
                     int start,
                     int num_bytes,
                     std::list<uint8>* data);
 
   // Helper to prepend an ASN.1 length field.
   void PrependLength(size_t size, std::list<uint8>* data);
 
@@ skipping 89 matching lines @@
   CSSM_KEY key_;
   CSSM_CSP_HANDLE csp_handle_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(RSAPrivateKey);
 };
 
 }  // namespace base
 
 #endif  // BASE_CRYPTO_RSA_PRIVATE_KEY_H_