Bitcoin ABC  0.28.12
P2P Digital Currency
message.cpp
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1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2020 The Bitcoin Core developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 
6 #include <hash.h> // For CHashWriter
7 #include <key.h> // For CKey
8 #include <key_io.h> // For DecodeDestination()
9 #include <pubkey.h> // For CPubKey
10 #include <script/standard.h> // For CTxDestination, IsValidDestination(), PKHash
11 #include <serialize.h> // For SER_GETHASH
12 #include <util/message.h>
13 #include <util/strencodings.h> // For DecodeBase64()
14 
15 #include <string>
16 #include <vector>
17 
22 const std::string MESSAGE_MAGIC = "eCash Signed Message:\n";
23 
25  const std::string &address,
26  const std::string &signature,
27  const std::string &message) {
28  CTxDestination destination = DecodeDestination(address, params);
29  if (!IsValidDestination(destination)) {
31  }
32 
33  if (std::get_if<PKHash>(&destination) == nullptr) {
35  }
36 
37  bool invalid = false;
38  std::vector<uint8_t> signature_bytes =
39  DecodeBase64(signature.c_str(), &invalid);
40  if (invalid) {
42  }
43 
44  CPubKey pubkey;
45  if (!pubkey.RecoverCompact(MessageHash(message), signature_bytes)) {
47  }
48 
49  if (!(CTxDestination(PKHash(pubkey)) == destination)) {
51  }
52 
54 }
55 
56 bool MessageSign(const CKey &privkey, const std::string &message,
57  std::string &signature) {
58  std::vector<uint8_t> signature_bytes;
59 
60  if (!privkey.SignCompact(MessageHash(message), signature_bytes)) {
61  return false;
62  }
63 
64  signature = EncodeBase64(signature_bytes);
65 
66  return true;
67 }
68 
69 uint256 MessageHash(const std::string &message) {
70  CHashWriter hasher(SER_GETHASH, 0);
71  hasher << MESSAGE_MAGIC << message;
72 
73  return hasher.GetHash();
74 }
75 
76 std::string SigningResultString(const SigningResult res) {
77  switch (res) {
78  case SigningResult::OK:
79  return "No error";
81  return "Private key not available";
83  return "Sign failed";
84  // no default case, so the compiler can warn about missing cases
85  }
86  assert(false);
87 }
CChainParams defines various tweakable parameters of a given instance of the Bitcoin system.
Definition: chainparams.h:74
A writer stream (for serialization) that computes a 256-bit hash.
Definition: hash.h:99
uint256 GetHash()
Compute the double-SHA256 hash of all data written to this object.
Definition: hash.h:122
An encapsulated secp256k1 private key.
Definition: key.h:28
bool SignCompact(const uint256 &hash, std::vector< uint8_t > &vchSig) const
Create a compact ECDSA signature (65 bytes), which allows reconstructing the used public key.
Definition: key.cpp:316
An encapsulated public key.
Definition: pubkey.h:31
bool RecoverCompact(const uint256 &hash, const std::vector< uint8_t > &vchSig)
Recover a public key from a compact ECDSA signature.
Definition: pubkey.cpp:227
256-bit opaque blob.
Definition: uint256.h:127
CTxDestination DecodeDestination(const std::string &addr, const CChainParams &params)
Definition: key_io.cpp:174
uint256 MessageHash(const std::string &message)
Hashes a message for signing and verification in a manner that prevents inadvertently signing a trans...
Definition: message.cpp:69
MessageVerificationResult MessageVerify(const CChainParams &params, const std::string &address, const std::string &signature, const std::string &message)
Verify a signed message.
Definition: message.cpp:24
bool MessageSign(const CKey &privkey, const std::string &message, std::string &signature)
Sign a message.
Definition: message.cpp:56
const std::string MESSAGE_MAGIC
Text used to signify that a signed message follows and to prevent inadvertently signing a transaction...
Definition: message.cpp:22
std::string SigningResultString(const SigningResult res)
Definition: message.cpp:76
SigningResult
Definition: message.h:47
@ PRIVATE_KEY_NOT_AVAILABLE
@ OK
No error.
MessageVerificationResult
The result of a signed message verification.
Definition: message.h:26
@ ERR_MALFORMED_SIGNATURE
The provided signature couldn't be parsed (maybe invalid base64).
@ ERR_INVALID_ADDRESS
The provided address is invalid.
@ ERR_ADDRESS_NO_KEY
The provided address is valid but does not refer to a public key.
@ ERR_NOT_SIGNED
The message was not signed with the private key of the provided address.
@ OK
The message verification was successful.
@ ERR_PUBKEY_NOT_RECOVERED
A public key could not be recovered from the provided signature and message.
@ SER_GETHASH
Definition: serialize.h:168
bool IsValidDestination(const CTxDestination &dest)
Check whether a CTxDestination is a CNoDestination.
Definition: standard.cpp:260
std::variant< CNoDestination, PKHash, ScriptHash > CTxDestination
A txout script template with a specific destination.
Definition: standard.h:85
std::string EncodeBase64(Span< const uint8_t > input)
std::vector< uint8_t > DecodeBase64(const char *p, bool *pf_invalid)
assert(!tx.IsCoinBase())