1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2012 The Bitcoin Developers
3 // Distributed under the MIT/X11 software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
8 // Why base-58 instead of standard base-64 encoding?
9 // - Don't want 0OIl characters that look the same in some fonts and
10 // could be used to create visually identical looking account numbers.
11 // - A string with non-alphanumeric characters is not as easily accepted as an account number.
12 // - E-mail usually won't line-break if there's no punctuation to break at.
13 // - Double-clicking selects the whole number as one word if it's all alphanumeric.
15 #ifndef BITCOIN_BASE58_H
16 #define BITCOIN_BASE58_H
24 static const char* pszBase58
= "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
26 // Encode a byte sequence as a base58-encoded string
27 inline std::string
EncodeBase58(const unsigned char* pbegin
, const unsigned char* pend
)
33 // Convert big endian data to little endian
34 // Extra zero at the end make sure bignum will interpret as a positive number
35 std::vector
<unsigned char> vchTmp(pend
-pbegin
+1, 0);
36 reverse_copy(pbegin
, pend
, vchTmp
.begin());
38 // Convert little endian data to bignum
42 // Convert bignum to std::string
44 // Expected size increase from base58 conversion is approximately 137%
45 // use 138% to be safe
46 str
.reserve((pend
- pbegin
) * 138 / 100 + 1);
51 if (!BN_div(&dv
, &rem
, &bn
, &bn58
, pctx
))
52 throw bignum_error("EncodeBase58 : BN_div failed");
54 unsigned int c
= rem
.getulong();
58 // Leading zeroes encoded as base58 zeros
59 for (const unsigned char* p
= pbegin
; p
< pend
&& *p
== 0; p
++)
62 // Convert little endian std::string to big endian
63 reverse(str
.begin(), str
.end());
67 // Encode a byte vector as a base58-encoded string
68 inline std::string
EncodeBase58(const std::vector
<unsigned char>& vch
)
70 return EncodeBase58(&vch
[0], &vch
[0] + vch
.size());
73 // Decode a base58-encoded string psz into byte vector vchRet
74 // returns true if decoding is successful
75 inline bool DecodeBase58(const char* psz
, std::vector
<unsigned char>& vchRet
)
85 // Convert big endian string to bignum
86 for (const char* p
= psz
; *p
; p
++)
88 const char* p1
= strchr(pszBase58
, *p
);
97 bnChar
.setulong(p1
- pszBase58
);
98 if (!BN_mul(&bn
, &bn
, &bn58
, pctx
))
99 throw bignum_error("DecodeBase58 : BN_mul failed");
103 // Get bignum as little endian data
104 std::vector
<unsigned char> vchTmp
= bn
.getvch();
106 // Trim off sign byte if present
107 if (vchTmp
.size() >= 2 && vchTmp
.end()[-1] == 0 && vchTmp
.end()[-2] >= 0x80)
108 vchTmp
.erase(vchTmp
.end()-1);
110 // Restore leading zeros
111 int nLeadingZeros
= 0;
112 for (const char* p
= psz
; *p
== pszBase58
[0]; p
++)
114 vchRet
.assign(nLeadingZeros
+ vchTmp
.size(), 0);
116 // Convert little endian data to big endian
117 reverse_copy(vchTmp
.begin(), vchTmp
.end(), vchRet
.end() - vchTmp
.size());
121 // Decode a base58-encoded string str into byte vector vchRet
122 // returns true if decoding is successful
123 inline bool DecodeBase58(const std::string
& str
, std::vector
<unsigned char>& vchRet
)
125 return DecodeBase58(str
.c_str(), vchRet
);
131 // Encode a byte vector to a base58-encoded string, including checksum
132 inline std::string
EncodeBase58Check(const std::vector
<unsigned char>& vchIn
)
134 // add 4-byte hash check to the end
135 std::vector
<unsigned char> vch(vchIn
);
136 uint256 hash
= Hash(vch
.begin(), vch
.end());
137 vch
.insert(vch
.end(), (unsigned char*)&hash
, (unsigned char*)&hash
+ 4);
138 return EncodeBase58(vch
);
141 // Decode a base58-encoded string psz that includes a checksum, into byte vector vchRet
142 // returns true if decoding is successful
143 inline bool DecodeBase58Check(const char* psz
, std::vector
<unsigned char>& vchRet
)
145 if (!DecodeBase58(psz
, vchRet
))
147 if (vchRet
.size() < 4)
152 uint256 hash
= Hash(vchRet
.begin(), vchRet
.end()-4);
153 if (memcmp(&hash
, &vchRet
.end()[-4], 4) != 0)
158 vchRet
.resize(vchRet
.size()-4);
162 // Decode a base58-encoded string str that includes a checksum, into byte vector vchRet
163 // returns true if decoding is successful
164 inline bool DecodeBase58Check(const std::string
& str
, std::vector
<unsigned char>& vchRet
)
166 return DecodeBase58Check(str
.c_str(), vchRet
);
173 /** Base class for all base58-encoded data */
178 unsigned char nVersion
;
180 // the actually encoded data
181 std::vector
<unsigned char> vchData
;
191 // zero the memory, as it may contain sensitive data
192 if (!vchData
.empty())
193 memset(&vchData
[0], 0, vchData
.size());
196 void SetData(int nVersionIn
, const void* pdata
, size_t nSize
)
198 nVersion
= nVersionIn
;
199 vchData
.resize(nSize
);
200 if (!vchData
.empty())
201 memcpy(&vchData
[0], pdata
, nSize
);
204 void SetData(int nVersionIn
, const unsigned char *pbegin
, const unsigned char *pend
)
206 SetData(nVersionIn
, (void*)pbegin
, pend
- pbegin
);
210 bool SetString(const char* psz
)
212 std::vector
<unsigned char> vchTemp
;
213 DecodeBase58Check(psz
, vchTemp
);
220 nVersion
= vchTemp
[0];
221 vchData
.resize(vchTemp
.size() - 1);
222 if (!vchData
.empty())
223 memcpy(&vchData
[0], &vchTemp
[1], vchData
.size());
224 memset(&vchTemp
[0], 0, vchTemp
.size());
228 bool SetString(const std::string
& str
)
230 return SetString(str
.c_str());
233 std::string
ToString() const
235 std::vector
<unsigned char> vch(1, nVersion
);
236 vch
.insert(vch
.end(), vchData
.begin(), vchData
.end());
237 return EncodeBase58Check(vch
);
240 int CompareTo(const CBase58Data
& b58
) const
242 if (nVersion
< b58
.nVersion
) return -1;
243 if (nVersion
> b58
.nVersion
) return 1;
244 if (vchData
< b58
.vchData
) return -1;
245 if (vchData
> b58
.vchData
) return 1;
249 bool operator==(const CBase58Data
& b58
) const { return CompareTo(b58
) == 0; }
250 bool operator<=(const CBase58Data
& b58
) const { return CompareTo(b58
) <= 0; }
251 bool operator>=(const CBase58Data
& b58
) const { return CompareTo(b58
) >= 0; }
252 bool operator< (const CBase58Data
& b58
) const { return CompareTo(b58
) < 0; }
253 bool operator> (const CBase58Data
& b58
) const { return CompareTo(b58
) > 0; }
256 /** base58-encoded Bitcoin addresses.
257 * Public-key-hash-addresses have version 0 (or 111 testnet).
258 * The data vector contains RIPEMD160(SHA256(pubkey)), where pubkey is the serialized public key.
259 * Script-hash-addresses have version 5 (or 196 testnet).
260 * The data vector contains RIPEMD160(SHA256(cscript)), where cscript is the serialized redemption script.
262 class CBitcoinAddress
;
263 class CBitcoinAddressVisitor
: public boost::static_visitor
<bool>
266 CBitcoinAddress
*addr
;
268 CBitcoinAddressVisitor(CBitcoinAddress
*addrIn
) : addr(addrIn
) { }
269 bool operator()(const CKeyID
&id
) const;
270 bool operator()(const CScriptID
&id
) const;
271 bool operator()(const CNoDestination
&no
) const;
274 class CBitcoinAddress
: public CBase58Data
281 PUBKEY_ADDRESS_TEST
= 111,
282 SCRIPT_ADDRESS_TEST
= 196,
285 bool Set(const CKeyID
&id
) {
286 SetData(fTestNet
? PUBKEY_ADDRESS_TEST
: PUBKEY_ADDRESS
, &id
, 20);
290 bool Set(const CScriptID
&id
) {
291 SetData(fTestNet
? SCRIPT_ADDRESS_TEST
: SCRIPT_ADDRESS
, &id
, 20);
295 bool Set(const CTxDestination
&dest
)
297 return boost::apply_visitor(CBitcoinAddressVisitor(this), dest
);
302 unsigned int nExpectedSize
= 20;
303 bool fExpectTestNet
= false;
307 nExpectedSize
= 20; // Hash of public key
308 fExpectTestNet
= false;
311 nExpectedSize
= 20; // Hash of CScript
312 fExpectTestNet
= false;
315 case PUBKEY_ADDRESS_TEST
:
317 fExpectTestNet
= true;
319 case SCRIPT_ADDRESS_TEST
:
321 fExpectTestNet
= true;
327 return fExpectTestNet
== fTestNet
&& vchData
.size() == nExpectedSize
;
334 CBitcoinAddress(const CTxDestination
&dest
)
339 CBitcoinAddress(const std::string
& strAddress
)
341 SetString(strAddress
);
344 CBitcoinAddress(const char* pszAddress
)
346 SetString(pszAddress
);
349 CTxDestination
Get() const {
351 return CNoDestination();
354 case PUBKEY_ADDRESS_TEST
: {
356 memcpy(&id
, &vchData
[0], 20);
360 case SCRIPT_ADDRESS_TEST
: {
362 memcpy(&id
, &vchData
[0], 20);
363 return CScriptID(id
);
366 return CNoDestination();
369 bool GetKeyID(CKeyID
&keyID
) const {
374 case PUBKEY_ADDRESS_TEST
: {
376 memcpy(&id
, &vchData
[0], 20);
380 default: return false;
384 bool IsScript() const {
389 case SCRIPT_ADDRESS_TEST
: {
392 default: return false;
397 bool inline CBitcoinAddressVisitor::operator()(const CKeyID
&id
) const { return addr
->Set(id
); }
398 bool inline CBitcoinAddressVisitor::operator()(const CScriptID
&id
) const { return addr
->Set(id
); }
399 bool inline CBitcoinAddressVisitor::operator()(const CNoDestination
&id
) const { return false; }
401 /** A base58-encoded secret key */
402 class CBitcoinSecret
: public CBase58Data
405 void SetSecret(const CSecret
& vchSecret
, bool fCompressed
)
407 assert(vchSecret
.size() == 32);
408 SetData(fTestNet
? 239 : 128, &vchSecret
[0], vchSecret
.size());
410 vchData
.push_back(1);
413 CSecret
GetSecret(bool &fCompressedOut
)
416 vchSecret
.resize(32);
417 memcpy(&vchSecret
[0], &vchData
[0], 32);
418 fCompressedOut
= vchData
.size() == 33;
424 bool fExpectTestNet
= false;
431 fExpectTestNet
= true;
437 return fExpectTestNet
== fTestNet
&& (vchData
.size() == 32 || (vchData
.size() == 33 && vchData
[32] == 1));
440 bool SetString(const char* pszSecret
)
442 return CBase58Data::SetString(pszSecret
) && IsValid();
445 bool SetString(const std::string
& strSecret
)
447 return SetString(strSecret
.c_str());
450 CBitcoinSecret(const CSecret
& vchSecret
, bool fCompressed
)
452 SetSecret(vchSecret
, fCompressed
);