aboutsummaryrefslogtreecommitdiff
path: root/src/key_io.cpp
blob: 9e246c0b81f21853bb4e2ee70e9ee65970105963 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
// Copyright (c) 2014-2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <key_io.h>

#include <base58.h>
#include <bech32.h>
#include <util/strencodings.h>

#include <algorithm>
#include <assert.h>
#include <string.h>

/// Maximum witness length for Bech32 addresses.
static constexpr std::size_t BECH32_WITNESS_PROG_MAX_LEN = 40;

namespace {
class DestinationEncoder
{
private:
    const CChainParams& m_params;

public:
    explicit DestinationEncoder(const CChainParams& params) : m_params(params) {}

    std::string operator()(const PKHash& id) const
    {
        std::vector<unsigned char> data = m_params.Base58Prefix(CChainParams::PUBKEY_ADDRESS);
        data.insert(data.end(), id.begin(), id.end());
        return EncodeBase58Check(data);
    }

    std::string operator()(const ScriptHash& id) const
    {
        std::vector<unsigned char> data = m_params.Base58Prefix(CChainParams::SCRIPT_ADDRESS);
        data.insert(data.end(), id.begin(), id.end());
        return EncodeBase58Check(data);
    }

    std::string operator()(const WitnessV0KeyHash& id) const
    {
        std::vector<unsigned char> data = {0};
        data.reserve(33);
        ConvertBits<8, 5, true>([&](unsigned char c) { data.push_back(c); }, id.begin(), id.end());
        return bech32::Encode(bech32::Encoding::BECH32, m_params.Bech32HRP(), data);
    }

    std::string operator()(const WitnessV0ScriptHash& id) const
    {
        std::vector<unsigned char> data = {0};
        data.reserve(53);
        ConvertBits<8, 5, true>([&](unsigned char c) { data.push_back(c); }, id.begin(), id.end());
        return bech32::Encode(bech32::Encoding::BECH32, m_params.Bech32HRP(), data);
    }

    std::string operator()(const WitnessV1Taproot& tap) const
    {
        std::vector<unsigned char> data = {1};
        data.reserve(53);
        ConvertBits<8, 5, true>([&](unsigned char c) { data.push_back(c); }, tap.begin(), tap.end());
        return bech32::Encode(bech32::Encoding::BECH32M, m_params.Bech32HRP(), data);
    }

    std::string operator()(const WitnessUnknown& id) const
    {
        if (id.version < 1 || id.version > 16 || id.length < 2 || id.length > 40) {
            return {};
        }
        std::vector<unsigned char> data = {(unsigned char)id.version};
        data.reserve(1 + (id.length * 8 + 4) / 5);
        ConvertBits<8, 5, true>([&](unsigned char c) { data.push_back(c); }, id.program, id.program + id.length);
        return bech32::Encode(bech32::Encoding::BECH32M, m_params.Bech32HRP(), data);
    }

    std::string operator()(const CNoDestination& no) const { return {}; }
};

CTxDestination DecodeDestination(const std::string& str, const CChainParams& params, std::string& error_str)
{
    std::vector<unsigned char> data;
    uint160 hash;
    error_str = "";

    // Note this will be false if it is a valid Bech32 address for a different network
    bool is_bech32 = (ToLower(str.substr(0, params.Bech32HRP().size())) == params.Bech32HRP());

    if (!is_bech32 && DecodeBase58Check(str, data, 21)) {
        // base58-encoded Bitcoin addresses.
        // Public-key-hash-addresses have version 0 (or 111 testnet).
        // The data vector contains RIPEMD160(SHA256(pubkey)), where pubkey is the serialized public key.
        const std::vector<unsigned char>& pubkey_prefix = params.Base58Prefix(CChainParams::PUBKEY_ADDRESS);
        if (data.size() == hash.size() + pubkey_prefix.size() && std::equal(pubkey_prefix.begin(), pubkey_prefix.end(), data.begin())) {
            std::copy(data.begin() + pubkey_prefix.size(), data.end(), hash.begin());
            return PKHash(hash);
        }
        // Script-hash-addresses have version 5 (or 196 testnet).
        // The data vector contains RIPEMD160(SHA256(cscript)), where cscript is the serialized redemption script.
        const std::vector<unsigned char>& script_prefix = params.Base58Prefix(CChainParams::SCRIPT_ADDRESS);
        if (data.size() == hash.size() + script_prefix.size() && std::equal(script_prefix.begin(), script_prefix.end(), data.begin())) {
            std::copy(data.begin() + script_prefix.size(), data.end(), hash.begin());
            return ScriptHash(hash);
        }

        if (!std::equal(script_prefix.begin(), script_prefix.end(), data.begin()) &&
            !std::equal(pubkey_prefix.begin(), pubkey_prefix.end(), data.begin())) {
            error_str = "Invalid prefix for Base58-encoded address";
        } else {
            error_str = "Invalid length for Base58 address";
        }
        return CNoDestination();
    } else if (!is_bech32) {
        // Try Base58 decoding without the checksum, using a much larger max length
        if (!DecodeBase58(str, data, 100)) {
            error_str = "Invalid HRP or Base58 character in address";
        } else {
            error_str = "Invalid checksum or length of Base58 address";
        }
        return CNoDestination();
    }

    data.clear();
    const auto dec = bech32::Decode(str);
    if ((dec.encoding == bech32::Encoding::BECH32 || dec.encoding == bech32::Encoding::BECH32M) && dec.data.size() > 0) {
        // Bech32 decoding
        if (dec.hrp != params.Bech32HRP()) {
            error_str = "Invalid prefix for Bech32 address";
            return CNoDestination();
        }
        int version = dec.data[0]; // The first 5 bit symbol is the witness version (0-16)
        if (version == 0 && dec.encoding != bech32::Encoding::BECH32) {
            error_str = "Version 0 witness address must use Bech32 checksum";
            return CNoDestination();
        }
        if (version != 0 && dec.encoding != bech32::Encoding::BECH32M) {
            error_str = "Version 1+ witness address must use Bech32m checksum";
            return CNoDestination();
        }
        // The rest of the symbols are converted witness program bytes.
        data.reserve(((dec.data.size() - 1) * 5) / 8);
        if (ConvertBits<5, 8, false>([&](unsigned char c) { data.push_back(c); }, dec.data.begin() + 1, dec.data.end())) {
            if (version == 0) {
                {
                    WitnessV0KeyHash keyid;
                    if (data.size() == keyid.size()) {
                        std::copy(data.begin(), data.end(), keyid.begin());
                        return keyid;
                    }
                }
                {
                    WitnessV0ScriptHash scriptid;
                    if (data.size() == scriptid.size()) {
                        std::copy(data.begin(), data.end(), scriptid.begin());
                        return scriptid;
                    }
                }

                error_str = "Invalid Bech32 v0 address data size";
                return CNoDestination();
            }

            if (version == 1 && data.size() == WITNESS_V1_TAPROOT_SIZE) {
                static_assert(WITNESS_V1_TAPROOT_SIZE == WitnessV1Taproot::size());
                WitnessV1Taproot tap;
                std::copy(data.begin(), data.end(), tap.begin());
                return tap;
            }

            if (version > 16) {
                error_str = "Invalid Bech32 address witness version";
                return CNoDestination();
            }

            if (data.size() < 2 || data.size() > BECH32_WITNESS_PROG_MAX_LEN) {
                error_str = "Invalid Bech32 address data size";
                return CNoDestination();
            }

            WitnessUnknown unk;
            unk.version = version;
            std::copy(data.begin(), data.end(), unk.program);
            unk.length = data.size();
            return unk;
        }
    }

    //TODO: locate Bech32 errors
    error_str = "Error in Bech32 encoding";

    return CNoDestination();
}
} // namespace

CKey DecodeSecret(const std::string& str)
{
    CKey key;
    std::vector<unsigned char> data;
    if (DecodeBase58Check(str, data, 34)) {
        const std::vector<unsigned char>& privkey_prefix = Params().Base58Prefix(CChainParams::SECRET_KEY);
        if ((data.size() == 32 + privkey_prefix.size() || (data.size() == 33 + privkey_prefix.size() && data.back() == 1)) &&
            std::equal(privkey_prefix.begin(), privkey_prefix.end(), data.begin())) {
            bool compressed = data.size() == 33 + privkey_prefix.size();
            key.Set(data.begin() + privkey_prefix.size(), data.begin() + privkey_prefix.size() + 32, compressed);
        }
    }
    if (!data.empty()) {
        memory_cleanse(data.data(), data.size());
    }
    return key;
}

std::string EncodeSecret(const CKey& key)
{
    assert(key.IsValid());
    std::vector<unsigned char> data = Params().Base58Prefix(CChainParams::SECRET_KEY);
    data.insert(data.end(), key.begin(), key.end());
    if (key.IsCompressed()) {
        data.push_back(1);
    }
    std::string ret = EncodeBase58Check(data);
    memory_cleanse(data.data(), data.size());
    return ret;
}

CExtPubKey DecodeExtPubKey(const std::string& str)
{
    CExtPubKey key;
    std::vector<unsigned char> data;
    if (DecodeBase58Check(str, data, 78)) {
        const std::vector<unsigned char>& prefix = Params().Base58Prefix(CChainParams::EXT_PUBLIC_KEY);
        if (data.size() == BIP32_EXTKEY_SIZE + prefix.size() && std::equal(prefix.begin(), prefix.end(), data.begin())) {
            key.Decode(data.data() + prefix.size());
        }
    }
    return key;
}

std::string EncodeExtPubKey(const CExtPubKey& key)
{
    std::vector<unsigned char> data = Params().Base58Prefix(CChainParams::EXT_PUBLIC_KEY);
    size_t size = data.size();
    data.resize(size + BIP32_EXTKEY_SIZE);
    key.Encode(data.data() + size);
    std::string ret = EncodeBase58Check(data);
    return ret;
}

CExtKey DecodeExtKey(const std::string& str)
{
    CExtKey key;
    std::vector<unsigned char> data;
    if (DecodeBase58Check(str, data, 78)) {
        const std::vector<unsigned char>& prefix = Params().Base58Prefix(CChainParams::EXT_SECRET_KEY);
        if (data.size() == BIP32_EXTKEY_SIZE + prefix.size() && std::equal(prefix.begin(), prefix.end(), data.begin())) {
            key.Decode(data.data() + prefix.size());
        }
    }
    return key;
}

std::string EncodeExtKey(const CExtKey& key)
{
    std::vector<unsigned char> data = Params().Base58Prefix(CChainParams::EXT_SECRET_KEY);
    size_t size = data.size();
    data.resize(size + BIP32_EXTKEY_SIZE);
    key.Encode(data.data() + size);
    std::string ret = EncodeBase58Check(data);
    memory_cleanse(data.data(), data.size());
    return ret;
}

std::string EncodeDestination(const CTxDestination& dest)
{
    return std::visit(DestinationEncoder(Params()), dest);
}

CTxDestination DecodeDestination(const std::string& str, std::string& error_msg)
{
    return DecodeDestination(str, Params(), error_msg);
}

CTxDestination DecodeDestination(const std::string& str)
{
    std::string error_msg;
    return DecodeDestination(str, error_msg);
}

bool IsValidDestinationString(const std::string& str, const CChainParams& params)
{
    std::string error_msg;
    return IsValidDestination(DecodeDestination(str, params, error_msg));
}

bool IsValidDestinationString(const std::string& str)
{
    return IsValidDestinationString(str, Params());
}