1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef CRYPTO_SIGNATURE_CREATOR_H_
6 #define CRYPTO_SIGNATURE_CREATOR_H_
7 
8 #include <stdint.h>
9 
10 #include <memory>
11 #include <vector>
12 
13 #include "base/macros.h"
14 #include "build/build_config.h"
15 #include "crypto/crypto_export.h"
16 
17 #if defined(USE_OPENSSL)
18 // Forward declaration for openssl/*.h
19 typedef struct env_md_ctx_st EVP_MD_CTX;
20 #elif defined(USE_NSS_CERTS) || defined(OS_WIN) || defined(OS_MACOSX)
21 // Forward declaration.
22 struct SGNContextStr;
23 #endif
24 
25 namespace crypto {
26 
27 class RSAPrivateKey;
28 
29 // Signs data using a bare private key (as opposed to a full certificate).
30 // Currently can only sign data using SHA-1 or SHA-256 with RSA PKCS#1v1.5.
31 class CRYPTO_EXPORT SignatureCreator {
32  public:
33   // The set of supported hash functions. Extend as required.
34   enum HashAlgorithm {
35     SHA1,
36     SHA256,
37   };
38 
39   ~SignatureCreator();
40 
41   // Create an instance. The caller must ensure that the provided PrivateKey
42   // instance outlives the created SignatureCreator. Uses the HashAlgorithm
43   // specified.
44   static std::unique_ptr<SignatureCreator> Create(RSAPrivateKey* key,
45                                                   HashAlgorithm hash_alg);
46 
47   // Signs the precomputed |hash_alg| digest |data| using private |key| as
48   // specified in PKCS #1 v1.5.
49   static bool Sign(RSAPrivateKey* key,
50                    HashAlgorithm hash_alg,
51                    const uint8_t* data,
52                    int data_len,
53                    std::vector<uint8_t>* signature);
54 
55   // Update the signature with more data.
56   bool Update(const uint8_t* data_part, int data_part_len);
57 
58   // Finalize the signature.
59   bool Final(std::vector<uint8_t>* signature);
60 
61  private:
62   // Private constructor. Use the Create() method instead.
63   SignatureCreator();
64 
65 #if defined(USE_OPENSSL)
66   EVP_MD_CTX* sign_context_;
67 #elif defined(USE_NSS_CERTS) || defined(OS_WIN) || defined(OS_MACOSX)
68   SGNContextStr* sign_context_;
69 #endif
70 
71   DISALLOW_COPY_AND_ASSIGN(SignatureCreator);
72 };
73 
74 }  // namespace crypto
75 
76 #endif  // CRYPTO_SIGNATURE_CREATOR_H_
77