Bitcoin Core 29.99.0
P2P Digital Currency
encrypt.cpp
Go to the documentation of this file.
1// Copyright (c) 2011-2022 The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <rpc/util.h>
6#include <scheduler.h>
7#include <wallet/context.h>
8#include <wallet/rpc/util.h>
9#include <wallet/wallet.h>
10
11
12namespace wallet {
14{
15 return RPCHelpMan{
16 "walletpassphrase",
17 "Stores the wallet decryption key in memory for 'timeout' seconds.\n"
18 "This is needed prior to performing transactions related to private keys such as sending bitcoins\n"
19 "\nNote:\n"
20 "Issuing the walletpassphrase command while the wallet is already unlocked will set a new unlock\n"
21 "time that overrides the old one.\n",
22 {
23 {"passphrase", RPCArg::Type::STR, RPCArg::Optional::NO, "The wallet passphrase"},
24 {"timeout", RPCArg::Type::NUM, RPCArg::Optional::NO, "The time to keep the decryption key in seconds; capped at 100000000 (~3 years)."},
25 },
28 "\nUnlock the wallet for 60 seconds\n"
29 + HelpExampleCli("walletpassphrase", "\"my pass phrase\" 60") +
30 "\nLock the wallet again (before 60 seconds)\n"
31 + HelpExampleCli("walletlock", "") +
32 "\nAs a JSON-RPC call\n"
33 + HelpExampleRpc("walletpassphrase", "\"my pass phrase\", 60")
34 },
35 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
36{
37 std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
38 if (!wallet) return UniValue::VNULL;
39 CWallet* const pwallet = wallet.get();
40
41 int64_t nSleepTime;
42 int64_t relock_time;
43 // Prevent concurrent calls to walletpassphrase with the same wallet.
44 LOCK(pwallet->m_unlock_mutex);
45 {
46 LOCK(pwallet->cs_wallet);
47
48 if (!pwallet->IsCrypted()) {
49 throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE, "Error: running with an unencrypted wallet, but walletpassphrase was called.");
50 }
51
52 // Note that the walletpassphrase is stored in request.params[0] which is not mlock()ed
53 SecureString strWalletPass;
54 strWalletPass.reserve(100);
55 strWalletPass = std::string_view{request.params[0].get_str()};
56
57 // Get the timeout
58 nSleepTime = request.params[1].getInt<int64_t>();
59 // Timeout cannot be negative, otherwise it will relock immediately
60 if (nSleepTime < 0) {
61 throw JSONRPCError(RPC_INVALID_PARAMETER, "Timeout cannot be negative.");
62 }
63 // Clamp timeout
64 constexpr int64_t MAX_SLEEP_TIME = 100000000; // larger values trigger a macos/libevent bug?
65 if (nSleepTime > MAX_SLEEP_TIME) {
66 nSleepTime = MAX_SLEEP_TIME;
67 }
68
69 if (strWalletPass.empty()) {
70 throw JSONRPCError(RPC_INVALID_PARAMETER, "passphrase cannot be empty");
71 }
72
73 if (!pwallet->Unlock(strWalletPass)) {
74 // Check if the passphrase has a null character (see #27067 for details)
75 if (strWalletPass.find('\0') == std::string::npos) {
76 throw JSONRPCError(RPC_WALLET_PASSPHRASE_INCORRECT, "Error: The wallet passphrase entered was incorrect.");
77 } else {
78 throw JSONRPCError(RPC_WALLET_PASSPHRASE_INCORRECT, "Error: The wallet passphrase entered is incorrect. "
79 "It contains a null character (ie - a zero byte). "
80 "If the passphrase was set with a version of this software prior to 25.0, "
81 "please try again with only the characters up to — but not including — "
82 "the first null character. If this is successful, please set a new "
83 "passphrase to avoid this issue in the future.");
84 }
85 }
86
87 pwallet->TopUpKeyPool();
88
89 pwallet->nRelockTime = GetTime() + nSleepTime;
90 relock_time = pwallet->nRelockTime;
91 }
92
93 // Get wallet scheduler to queue up the relock callback in the future.
94 // Scheduled events don't get destructed until they are executed,
95 // and they are executed in series in a single scheduler thread so
96 // no cs_wallet lock is needed.
97 WalletContext& context = EnsureWalletContext(request.context);
98 // Keep a weak pointer to the wallet so that it is possible to unload the
99 // wallet before the following callback is called. If a valid shared pointer
100 // is acquired in the callback then the wallet is still loaded.
101 std::weak_ptr<CWallet> weak_wallet = wallet;
102 context.scheduler->scheduleFromNow([weak_wallet, relock_time] {
103 if (auto shared_wallet = weak_wallet.lock()) {
104 LOCK2(shared_wallet->m_relock_mutex, shared_wallet->cs_wallet);
105 // Skip if this is not the most recent relock callback.
106 if (shared_wallet->nRelockTime != relock_time) return;
107 shared_wallet->Lock();
108 shared_wallet->nRelockTime = 0;
109 }
110 }, std::chrono::seconds(nSleepTime));
111
112 return UniValue::VNULL;
113},
114 };
115}
116
117
119{
120 return RPCHelpMan{
121 "walletpassphrasechange",
122 "Changes the wallet passphrase from 'oldpassphrase' to 'newpassphrase'.\n",
123 {
124 {"oldpassphrase", RPCArg::Type::STR, RPCArg::Optional::NO, "The current passphrase"},
125 {"newpassphrase", RPCArg::Type::STR, RPCArg::Optional::NO, "The new passphrase"},
126 },
129 HelpExampleCli("walletpassphrasechange", "\"old one\" \"new one\"")
130 + HelpExampleRpc("walletpassphrasechange", "\"old one\", \"new one\"")
131 },
132 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
133{
134 std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
135 if (!pwallet) return UniValue::VNULL;
136
137 if (!pwallet->IsCrypted()) {
138 throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE, "Error: running with an unencrypted wallet, but walletpassphrasechange was called.");
139 }
140
141 if (pwallet->IsScanningWithPassphrase()) {
142 throw JSONRPCError(RPC_WALLET_ERROR, "Error: the wallet is currently being used to rescan the blockchain for related transactions. Please call `abortrescan` before changing the passphrase.");
143 }
144
145 LOCK2(pwallet->m_relock_mutex, pwallet->cs_wallet);
146
147 SecureString strOldWalletPass;
148 strOldWalletPass.reserve(100);
149 strOldWalletPass = std::string_view{request.params[0].get_str()};
150
151 SecureString strNewWalletPass;
152 strNewWalletPass.reserve(100);
153 strNewWalletPass = std::string_view{request.params[1].get_str()};
154
155 if (strOldWalletPass.empty() || strNewWalletPass.empty()) {
156 throw JSONRPCError(RPC_INVALID_PARAMETER, "passphrase cannot be empty");
157 }
158
159 if (!pwallet->ChangeWalletPassphrase(strOldWalletPass, strNewWalletPass)) {
160 // Check if the old passphrase had a null character (see #27067 for details)
161 if (strOldWalletPass.find('\0') == std::string::npos) {
162 throw JSONRPCError(RPC_WALLET_PASSPHRASE_INCORRECT, "Error: The wallet passphrase entered was incorrect.");
163 } else {
164 throw JSONRPCError(RPC_WALLET_PASSPHRASE_INCORRECT, "Error: The old wallet passphrase entered is incorrect. "
165 "It contains a null character (ie - a zero byte). "
166 "If the old passphrase was set with a version of this software prior to 25.0, "
167 "please try again with only the characters up to — but not including — "
168 "the first null character.");
169 }
170 }
171
172 return UniValue::VNULL;
173},
174 };
175}
176
177
179{
180 return RPCHelpMan{
181 "walletlock",
182 "Removes the wallet encryption key from memory, locking the wallet.\n"
183 "After calling this method, you will need to call walletpassphrase again\n"
184 "before being able to call any methods which require the wallet to be unlocked.\n",
185 {},
188 "\nSet the passphrase for 2 minutes to perform a transaction\n"
189 + HelpExampleCli("walletpassphrase", "\"my pass phrase\" 120") +
190 "\nPerform a send (requires passphrase set)\n"
191 + HelpExampleCli("sendtoaddress", "\"" + EXAMPLE_ADDRESS[0] + "\" 1.0") +
192 "\nClear the passphrase since we are done before 2 minutes is up\n"
193 + HelpExampleCli("walletlock", "") +
194 "\nAs a JSON-RPC call\n"
195 + HelpExampleRpc("walletlock", "")
196 },
197 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
198{
199 std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
200 if (!pwallet) return UniValue::VNULL;
201
202 if (!pwallet->IsCrypted()) {
203 throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE, "Error: running with an unencrypted wallet, but walletlock was called.");
204 }
205
206 if (pwallet->IsScanningWithPassphrase()) {
207 throw JSONRPCError(RPC_WALLET_ERROR, "Error: the wallet is currently being used to rescan the blockchain for related transactions. Please call `abortrescan` before locking the wallet.");
208 }
209
210 LOCK2(pwallet->m_relock_mutex, pwallet->cs_wallet);
211
212 pwallet->Lock();
213 pwallet->nRelockTime = 0;
214
215 return UniValue::VNULL;
216},
217 };
218}
219
220
222{
223 return RPCHelpMan{
224 "encryptwallet",
225 "Encrypts the wallet with 'passphrase'. This is for first time encryption.\n"
226 "After this, any calls that interact with private keys such as sending or signing \n"
227 "will require the passphrase to be set prior to making these calls.\n"
228 "Use the walletpassphrase call for this, and then walletlock call.\n"
229 "If the wallet is already encrypted, use the walletpassphrasechange call.\n"
230 "** IMPORTANT **\n"
231 "For security reasons, the encryption process will generate a new HD seed, resulting\n"
232 "in the creation of a fresh set of active descriptors. Therefore, it is crucial to\n"
233 "securely back up the newly generated wallet file using the backupwallet RPC.\n",
234 {
235 {"passphrase", RPCArg::Type::STR, RPCArg::Optional::NO, "The pass phrase to encrypt the wallet with. It must be at least 1 character, but should be long."},
236 },
237 RPCResult{RPCResult::Type::STR, "", "A string with further instructions"},
239 "\nEncrypt your wallet\n"
240 + HelpExampleCli("encryptwallet", "\"my pass phrase\"") +
241 "\nNow set the passphrase to use the wallet, such as for signing or sending bitcoin\n"
242 + HelpExampleCli("walletpassphrase", "\"my pass phrase\"") +
243 "\nNow we can do something like sign\n"
244 + HelpExampleCli("signmessage", "\"address\" \"test message\"") +
245 "\nNow lock the wallet again by removing the passphrase\n"
246 + HelpExampleCli("walletlock", "") +
247 "\nAs a JSON-RPC call\n"
248 + HelpExampleRpc("encryptwallet", "\"my pass phrase\"")
249 },
250 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
251{
252 std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
253 if (!pwallet) return UniValue::VNULL;
254
255 if (pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS)) {
256 throw JSONRPCError(RPC_WALLET_ENCRYPTION_FAILED, "Error: wallet does not contain private keys, nothing to encrypt.");
257 }
258
259 if (pwallet->IsCrypted()) {
260 throw JSONRPCError(RPC_WALLET_WRONG_ENC_STATE, "Error: running with an encrypted wallet, but encryptwallet was called.");
261 }
262
263 if (pwallet->IsScanningWithPassphrase()) {
264 throw JSONRPCError(RPC_WALLET_ERROR, "Error: the wallet is currently being used to rescan the blockchain for related transactions. Please call `abortrescan` before encrypting the wallet.");
265 }
266
267 LOCK2(pwallet->m_relock_mutex, pwallet->cs_wallet);
268
269 SecureString strWalletPass;
270 strWalletPass.reserve(100);
271 strWalletPass = std::string_view{request.params[0].get_str()};
272
273 if (strWalletPass.empty()) {
274 throw JSONRPCError(RPC_INVALID_PARAMETER, "passphrase cannot be empty");
275 }
276
277 if (!pwallet->EncryptWallet(strWalletPass)) {
278 throw JSONRPCError(RPC_WALLET_ENCRYPTION_FAILED, "Error: Failed to encrypt the wallet.");
279 }
280
281 return "wallet encrypted; The keypool has been flushed and a new HD seed was generated. You need to make a new backup with the backupwallet RPC.";
282},
283 };
284}
285} // namespace wallet
void scheduleFromNow(Function f, std::chrono::milliseconds delta) EXCLUSIVE_LOCKS_REQUIRED(!newTaskMutex)
Call f once after the delta has passed.
Definition: scheduler.h:53
@ VNULL
Definition: univalue.h:24
A CWallet maintains a set of transactions and balances, and provides the ability to create new transa...
Definition: wallet.h:311
bool TopUpKeyPool(unsigned int kpSize=0)
Definition: wallet.cpp:2479
bool IsCrypted() const
Definition: wallet.cpp:3278
bool Unlock(const CKeyingMaterial &vMasterKeyIn)
Definition: wallet.cpp:3309
Mutex m_unlock_mutex
Definition: wallet.h:597
RecursiveMutex cs_wallet
Main wallet lock.
Definition: wallet.h:461
RPCHelpMan walletlock()
Definition: encrypt.cpp:178
std::shared_ptr< CWallet > GetWalletForJSONRPCRequest(const JSONRPCRequest &request)
Figures out what wallet, if any, to use for a JSONRPCRequest.
Definition: util.cpp:63
RPCHelpMan walletpassphrase()
Definition: encrypt.cpp:13
WalletContext & EnsureWalletContext(const std::any &context)
Definition: util.cpp:94
RPCHelpMan walletpassphrasechange()
Definition: encrypt.cpp:118
RPCHelpMan encryptwallet()
Definition: encrypt.cpp:221
@ WALLET_FLAG_DISABLE_PRIVATE_KEYS
Definition: walletutil.h:30
UniValue JSONRPCError(int code, const std::string &message)
Definition: request.cpp:70
@ RPC_WALLET_WRONG_ENC_STATE
Command given in wrong wallet encryption state (encrypting an encrypted wallet etc....
Definition: protocol.h:77
@ RPC_WALLET_ENCRYPTION_FAILED
Failed to encrypt the wallet.
Definition: protocol.h:78
@ RPC_INVALID_PARAMETER
Invalid, missing or duplicate parameter.
Definition: protocol.h:44
@ RPC_WALLET_ERROR
Wallet errors.
Definition: protocol.h:71
@ RPC_WALLET_PASSPHRASE_INCORRECT
The wallet passphrase entered was incorrect.
Definition: protocol.h:76
std::string HelpExampleCli(const std::string &methodname, const std::string &args)
Definition: util.cpp:186
std::string HelpExampleRpc(const std::string &methodname, const std::string &args)
Definition: util.cpp:204
const std::string EXAMPLE_ADDRESS[2]
Example bech32 addresses for the RPCExamples help documentation.
Definition: util.cpp:47
std::basic_string< char, std::char_traits< char >, secure_allocator< char > > SecureString
Definition: secure.h:58
@ NO
Required arg.
WalletContext struct containing references to state shared between CWallet instances,...
Definition: context.h:36
CScheduler * scheduler
Definition: context.h:38
#define LOCK2(cs1, cs2)
Definition: sync.h:260
#define LOCK(cs)
Definition: sync.h:259
int64_t GetTime()
DEPRECATED Use either ClockType::now() or Now<TimePointType>() if a cast is needed.
Definition: time.cpp:77