aboutsummaryrefslogtreecommitdiff
path: root/src/httprpc.cpp
blob: 96cccd8de93c7e86ebe2855bc09638f118b8ab92 (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
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
// Copyright (c) 2015-2021 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 <httprpc.h>

#include <chainparams.h>
#include <crypto/hmac_sha256.h>
#include <httpserver.h>
#include <rpc/protocol.h>
#include <rpc/server.h>
#include <util/strencodings.h>
#include <util/string.h>
#include <util/system.h>
#include <util/translation.h>
#include <walletinitinterface.h>

#include <algorithm>
#include <iterator>
#include <map>
#include <memory>
#include <stdio.h>
#include <set>
#include <string>

#include <boost/algorithm/string.hpp>

/** WWW-Authenticate to present with 401 Unauthorized response */
static const char* WWW_AUTH_HEADER_DATA = "Basic realm=\"jsonrpc\"";

/** Simple one-shot callback timer to be used by the RPC mechanism to e.g.
 * re-lock the wallet.
 */
class HTTPRPCTimer : public RPCTimerBase
{
public:
    HTTPRPCTimer(struct event_base* eventBase, std::function<void()>& func, int64_t millis) :
        ev(eventBase, false, func)
    {
        struct timeval tv;
        tv.tv_sec = millis/1000;
        tv.tv_usec = (millis%1000)*1000;
        ev.trigger(&tv);
    }
private:
    HTTPEvent ev;
};

class HTTPRPCTimerInterface : public RPCTimerInterface
{
public:
    explicit HTTPRPCTimerInterface(struct event_base* _base) : base(_base)
    {
    }
    const char* Name() override
    {
        return "HTTP";
    }
    RPCTimerBase* NewTimer(std::function<void()>& func, int64_t millis) override
    {
        return new HTTPRPCTimer(base, func, millis);
    }
private:
    struct event_base* base;
};


/* Pre-base64-encoded authentication token */
static std::string strRPCUserColonPass;
/* Stored RPC timer interface (for unregistration) */
static std::unique_ptr<HTTPRPCTimerInterface> httpRPCTimerInterface;
/* List of -rpcauth values */
static std::vector<std::vector<std::string>> g_rpcauth;
/* RPC Auth Whitelist */
static std::map<std::string, std::set<std::string>> g_rpc_whitelist;
static bool g_rpc_whitelist_default = false;

static void JSONErrorReply(HTTPRequest* req, const UniValue& objError, const UniValue& id)
{
    // Send error reply from json-rpc error object
    int nStatus = HTTP_INTERNAL_SERVER_ERROR;
    int code = find_value(objError, "code").get_int();

    if (code == RPC_INVALID_REQUEST)
        nStatus = HTTP_BAD_REQUEST;
    else if (code == RPC_METHOD_NOT_FOUND)
        nStatus = HTTP_NOT_FOUND;

    std::string strReply = JSONRPCReply(NullUniValue, objError, id);

    req->WriteHeader("Content-Type", "application/json");
    req->WriteReply(nStatus, strReply);
}

//This function checks username and password against -rpcauth
//entries from config file.
static bool multiUserAuthorized(std::string strUserPass)
{
    if (strUserPass.find(':') == std::string::npos) {
        return false;
    }
    std::string strUser = strUserPass.substr(0, strUserPass.find(':'));
    std::string strPass = strUserPass.substr(strUserPass.find(':') + 1);

    for (const auto& vFields : g_rpcauth) {
        std::string strName = vFields[0];
        if (!TimingResistantEqual(strName, strUser)) {
            continue;
        }

        std::string strSalt = vFields[1];
        std::string strHash = vFields[2];

        static const unsigned int KEY_SIZE = 32;
        unsigned char out[KEY_SIZE];

        CHMAC_SHA256(reinterpret_cast<const unsigned char*>(strSalt.data()), strSalt.size()).Write(reinterpret_cast<const unsigned char*>(strPass.data()), strPass.size()).Finalize(out);
        std::vector<unsigned char> hexvec(out, out+KEY_SIZE);
        std::string strHashFromPass = HexStr(hexvec);

        if (TimingResistantEqual(strHashFromPass, strHash)) {
            return true;
        }
    }
    return false;
}

static bool RPCAuthorized(const std::string& strAuth, std::string& strAuthUsernameOut)
{
    if (strRPCUserColonPass.empty()) // Belt-and-suspenders measure if InitRPCAuthentication was not called
        return false;
    if (strAuth.substr(0, 6) != "Basic ")
        return false;
    std::string strUserPass64 = TrimString(strAuth.substr(6));
    bool invalid;
    std::vector<unsigned char> userpass_data = DecodeBase64(strUserPass64, &invalid);
    if (invalid) return false;
    std::string strUserPass(userpass_data.begin(), userpass_data.end());

    if (strUserPass.find(':') != std::string::npos)
        strAuthUsernameOut = strUserPass.substr(0, strUserPass.find(':'));

    //Check if authorized under single-user field
    if (TimingResistantEqual(strUserPass, strRPCUserColonPass)) {
        return true;
    }
    return multiUserAuthorized(strUserPass);
}

static bool HTTPReq_JSONRPC(const std::any& context, HTTPRequest* req)
{
    // JSONRPC handles only POST
    if (req->GetRequestMethod() != HTTPRequest::POST) {
        req->WriteReply(HTTP_BAD_METHOD, "JSONRPC server handles only POST requests");
        return false;
    }
    // Check authorization
    std::pair<bool, std::string> authHeader = req->GetHeader("authorization");
    if (!authHeader.first) {
        req->WriteHeader("WWW-Authenticate", WWW_AUTH_HEADER_DATA);
        req->WriteReply(HTTP_UNAUTHORIZED);
        return false;
    }

    JSONRPCRequest jreq;
    jreq.context = context;
    jreq.peerAddr = req->GetPeer().ToString();
    if (!RPCAuthorized(authHeader.second, jreq.authUser)) {
        LogPrintf("ThreadRPCServer incorrect password attempt from %s\n", jreq.peerAddr);

        /* Deter brute-forcing
           If this results in a DoS the user really
           shouldn't have their RPC port exposed. */
        UninterruptibleSleep(std::chrono::milliseconds{250});

        req->WriteHeader("WWW-Authenticate", WWW_AUTH_HEADER_DATA);
        req->WriteReply(HTTP_UNAUTHORIZED);
        return false;
    }

    try {
        // Parse request
        UniValue valRequest;
        if (!valRequest.read(req->ReadBody()))
            throw JSONRPCError(RPC_PARSE_ERROR, "Parse error");

        // Set the URI
        jreq.URI = req->GetURI();

        std::string strReply;
        bool user_has_whitelist = g_rpc_whitelist.count(jreq.authUser);
        if (!user_has_whitelist && g_rpc_whitelist_default) {
            LogPrintf("RPC User %s not allowed to call any methods\n", jreq.authUser);
            req->WriteReply(HTTP_FORBIDDEN);
            return false;

        // singleton request
        } else if (valRequest.isObject()) {
            jreq.parse(valRequest);
            if (user_has_whitelist && !g_rpc_whitelist[jreq.authUser].count(jreq.strMethod)) {
                LogPrintf("RPC User %s not allowed to call method %s\n", jreq.authUser, jreq.strMethod);
                req->WriteReply(HTTP_FORBIDDEN);
                return false;
            }
            UniValue result = tableRPC.execute(jreq);

            // Send reply
            strReply = JSONRPCReply(result, NullUniValue, jreq.id);

        // array of requests
        } else if (valRequest.isArray()) {
            if (user_has_whitelist) {
                for (unsigned int reqIdx = 0; reqIdx < valRequest.size(); reqIdx++) {
                    if (!valRequest[reqIdx].isObject()) {
                        throw JSONRPCError(RPC_INVALID_REQUEST, "Invalid Request object");
                    } else {
                        const UniValue& request = valRequest[reqIdx].get_obj();
                        // Parse method
                        std::string strMethod = find_value(request, "method").get_str();
                        if (!g_rpc_whitelist[jreq.authUser].count(strMethod)) {
                            LogPrintf("RPC User %s not allowed to call method %s\n", jreq.authUser, strMethod);
                            req->WriteReply(HTTP_FORBIDDEN);
                            return false;
                        }
                    }
                }
            }
            strReply = JSONRPCExecBatch(jreq, valRequest.get_array());
        }
        else
            throw JSONRPCError(RPC_PARSE_ERROR, "Top-level object parse error");

        req->WriteHeader("Content-Type", "application/json");
        req->WriteReply(HTTP_OK, strReply);
    } catch (const UniValue& objError) {
        JSONErrorReply(req, objError, jreq.id);
        return false;
    } catch (const std::exception& e) {
        JSONErrorReply(req, JSONRPCError(RPC_PARSE_ERROR, e.what()), jreq.id);
        return false;
    }
    return true;
}

static bool InitRPCAuthentication()
{
    if (gArgs.GetArg("-rpcpassword", "") == "")
    {
        LogPrintf("Using random cookie authentication.\n");
        if (!GenerateAuthCookie(&strRPCUserColonPass)) {
            return false;
        }
    } else {
        LogPrintf("Config options rpcuser and rpcpassword will soon be deprecated. Locally-run instances may remove rpcuser to use cookie-based auth, or may be replaced with rpcauth. Please see share/rpcauth for rpcauth auth generation.\n");
        strRPCUserColonPass = gArgs.GetArg("-rpcuser", "") + ":" + gArgs.GetArg("-rpcpassword", "");
    }
    if (gArgs.GetArg("-rpcauth","") != "")
    {
        LogPrintf("Using rpcauth authentication.\n");
        for (const std::string& rpcauth : gArgs.GetArgs("-rpcauth")) {
            std::vector<std::string> fields;
            boost::split(fields, rpcauth, boost::is_any_of(":$"));
            if (fields.size() == 3) {
                g_rpcauth.push_back(fields);
            } else {
                LogPrintf("Invalid -rpcauth argument.\n");
                return false;
            }
        }
    }

    g_rpc_whitelist_default = gArgs.GetBoolArg("-rpcwhitelistdefault", gArgs.IsArgSet("-rpcwhitelist"));
    for (const std::string& strRPCWhitelist : gArgs.GetArgs("-rpcwhitelist")) {
        auto pos = strRPCWhitelist.find(':');
        std::string strUser = strRPCWhitelist.substr(0, pos);
        bool intersect = g_rpc_whitelist.count(strUser);
        std::set<std::string>& whitelist = g_rpc_whitelist[strUser];
        if (pos != std::string::npos) {
            std::string strWhitelist = strRPCWhitelist.substr(pos + 1);
            std::set<std::string> new_whitelist;
            boost::split(new_whitelist, strWhitelist, boost::is_any_of(", "));
            if (intersect) {
                std::set<std::string> tmp_whitelist;
                std::set_intersection(new_whitelist.begin(), new_whitelist.end(),
                       whitelist.begin(), whitelist.end(), std::inserter(tmp_whitelist, tmp_whitelist.end()));
                new_whitelist = std::move(tmp_whitelist);
            }
            whitelist = std::move(new_whitelist);
        }
    }

    return true;
}

bool StartHTTPRPC(const std::any& context)
{
    LogPrint(BCLog::RPC, "Starting HTTP RPC server\n");
    if (!InitRPCAuthentication())
        return false;

    auto handle_rpc = [context](HTTPRequest* req, const std::string&) { return HTTPReq_JSONRPC(context, req); };
    RegisterHTTPHandler("/", true, handle_rpc);
    if (g_wallet_init_interface.HasWalletSupport()) {
        RegisterHTTPHandler("/wallet/", false, handle_rpc);
    }
    struct event_base* eventBase = EventBase();
    assert(eventBase);
    httpRPCTimerInterface = std::make_unique<HTTPRPCTimerInterface>(eventBase);
    RPCSetTimerInterface(httpRPCTimerInterface.get());
    return true;
}

void InterruptHTTPRPC()
{
    LogPrint(BCLog::RPC, "Interrupting HTTP RPC server\n");
}

void StopHTTPRPC()
{
    LogPrint(BCLog::RPC, "Stopping HTTP RPC server\n");
    UnregisterHTTPHandler("/", true);
    if (g_wallet_init_interface.HasWalletSupport()) {
        UnregisterHTTPHandler("/wallet/", false);
    }
    if (httpRPCTimerInterface) {
        RPCUnsetTimerInterface(httpRPCTimerInterface.get());
        httpRPCTimerInterface.reset();
    }
}