bitcoin-cli.cpp

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2016 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#if defined(HAVE_CONFIG_H)
#include "config/bitcoin-config.h"
#endif

#include "chainparamsbase.h"
#include "clientversion.h"
#include "rpc/client.h"
#include "rpc/protocol.h"
#include "support/events.h"
#include "util.h"
#include "fs_util.h"
#include "utilstrencodings.h"

#include <cstdio>

#include <event2/buffer.h>
#include <event2/keyvalq_struct.h>

#include <univalue.h>

static const char DEFAULT_RPCCONNECT[] = "127.0.0.1";
static const int DEFAULT_HTTP_CLIENT_TIMEOUT = 900;
static const bool DEFAULT_NAMED = false;
static const int CONTINUE_EXECUTION = -1;

std::string HelpMessageCli() {
    const auto defaultBaseParams =
        CreateBaseChainParams(CBaseChainParams::MAIN);
    const auto testnetBaseParams =
        CreateBaseChainParams(CBaseChainParams::TESTNET);
    std::string strUsage;
    strUsage += HelpMessageGroup(_("Options:"));
    strUsage += HelpMessageOpt("-?", _("This help message"));
    strUsage += HelpMessageOpt(
        "-conf=<file>", strprintf(_("Specify configuration file (default: %s)"),
                                  BITCOIN_CONF_FILENAME));
    strUsage += HelpMessageOpt("-datadir=<dir>", _("Specify data directory"));
    strUsage += HelpMessageOpt(
        "-getinfo",
        _("Get general information from the remote server. Note that unlike "
          "server-side RPC calls, the results of -getinfo is the result of "
          "multiple non-atomic requests. Some entries in the result may "
          "represent results from different states (e.g. wallet balance may be "
          "as of a different block from the chain state reported)"));
    AppendParamsHelpMessages(strUsage);
    strUsage += HelpMessageOpt(
        "-named",
        strprintf(_("Pass named instead of positional arguments (default: %s)"),
                  DEFAULT_NAMED));
    strUsage += HelpMessageOpt(
        "-rpcconnect=<ip>",
        strprintf(_("Send commands to node running on <ip> (default: %s)"),
                  DEFAULT_RPCCONNECT));
    strUsage += HelpMessageOpt(
        "-rpcport=<port>",
        strprintf(
            _("Connect to JSON-RPC on <port> (default: %u or testnet: %u)"),
            defaultBaseParams->RPCPort(), testnetBaseParams->RPCPort()));
    strUsage += HelpMessageOpt("-rpcwait", _("Wait for RPC server to start"));
    strUsage += HelpMessageOpt("-rpcuser=<user>",
                               _("Username for JSON-RPC connections"));
    strUsage += HelpMessageOpt("-rpcpassword=<pw>",
                               _("Password for JSON-RPC connections"));
    strUsage +=
        HelpMessageOpt("-rpcclienttimeout=<n>",
                       strprintf(_("Timeout in seconds during HTTP requests, "
                                   "or 0 for no timeout. (default: %d)"),
                                 DEFAULT_HTTP_CLIENT_TIMEOUT));

    strUsage += HelpMessageOpt(
        "-stdinrpcpass",
        strprintf(_("Read RPC password from standard input as a single line.  "
                    "When combined with -stdin, the first line from standard "
                    "input is used for the RPC password.")));
    strUsage += HelpMessageOpt(
        "-stdin", _("Read extra arguments from standard input, one per line "
                    "until EOF/Ctrl-D (recommended for sensitive information "
                    "such as passphrases)"));
    strUsage += HelpMessageOpt(
        "-rpcwallet=<walletname>",
        _("Send RPC for non-default wallet on RPC server (argument is wallet "
          "filename in bitcoind directory, required if bitcoind/-Qt runs with "
          "multiple wallets)"));

    return strUsage;
}

//////////////////////////////////////////////////////////////////////////////
//
// Start
//

//
// Exception thrown on connection error.  This error is used to determine when
// to wait if -rpcwait is given.
//
class CConnectionFailed : public std::runtime_error {
public:
    explicit inline CConnectionFailed(const std::string &msg)
        : std::runtime_error(msg) {}
};

//
// This function returns either one of EXIT_ codes when it's expected to stop
// the process or CONTINUE_EXECUTION when it's expected to continue further.
//
static int AppInitRPC(int argc, char *argv[]) {
    //
    // Parameters
    //
    gArgs.ParseParameters(argc, argv);
    if (argc < 2 || HelpRequested(gArgs) || gArgs.IsArgSet("-version")) {
        std::string strUsage =
            strprintf(_("%s RPC client version"), _(PACKAGE_NAME)) + " " +
            FormatFullVersion() + "\n";
        if (!gArgs.IsArgSet("-version")) {
            strUsage +=
                "\n" + _("Usage:") + "\n" +
                "  bitcoin-cli [options] <command> [params]  " +
                strprintf(_("Send command to %s"), _(PACKAGE_NAME)) + "\n" +
                "  bitcoin-cli [options] -named <command> [name=value] ... " +
                strprintf(_("Send command to %s (with named arguments)"),
                          _(PACKAGE_NAME)) +
                "\n" + "  bitcoin-cli [options] help                " +
                _("List commands") + "\n" +
                "  bitcoin-cli [options] help <command>      " +
                _("Get help for a command") + "\n";

            strUsage += "\n" + HelpMessageCli();
        }

        fprintf(stdout, "%s", strUsage.c_str());
        if (argc < 2) {
            fprintf(stderr, "Error: too few parameters\n");
            return EXIT_FAILURE;
        }
        return EXIT_SUCCESS;
    }
    if (!fs::is_directory(GetDataDir(false))) {
        fprintf(stderr,
                "Error: Specified data directory \"%s\" does not exist.\n",
                gArgs.GetArg("-datadir", "").c_str());
        return EXIT_FAILURE;
    }
    try {
        gArgs.ReadConfigFile(gArgs.GetArg("-conf", BITCOIN_CONF_FILENAME));
    } catch (const std::exception &e) {
        fprintf(stderr, "Error reading configuration file: %s\n", e.what());
        return EXIT_FAILURE;
    }
    // Check for -testnet or -regtest parameter (BaseParams() calls are only
    // valid after this clause)
    try {
        SelectBaseParams(gArgs.GetChainName());
    } catch (const std::exception &e) {
        fprintf(stderr, "Error: %s\n", e.what());
        return EXIT_FAILURE;
    }
    if (gArgs.GetBoolArg("-rpcssl", false)) {
        fprintf(stderr,
                "Error: SSL mode for RPC (-rpcssl) is no longer supported.\n");
        return EXIT_FAILURE;
    }
    return CONTINUE_EXECUTION;
}

/** Reply structure for request_done to fill in */
struct HTTPReply {
    HTTPReply() : status(0), error(-1) {}

    int status;
    int error;
    std::string body;
};

const char *http_errorstring(int code) {
    switch (code) {
#if LIBEVENT_VERSION_NUMBER >= 0x02010300
        case EVREQ_HTTP_TIMEOUT:
            return "timeout reached";
        case EVREQ_HTTP_EOF:
            return "EOF reached";
        case EVREQ_HTTP_INVALID_HEADER:
            return "error while reading header, or invalid header";
        case EVREQ_HTTP_BUFFER_ERROR:
            return "error encountered while reading or writing";
        case EVREQ_HTTP_REQUEST_CANCEL:
            return "request was canceled";
        case EVREQ_HTTP_DATA_TOO_LONG:
            return "response body is larger than allowed";
#endif
        default:
            return "unknown";
    }
}

static void http_request_done(struct evhttp_request *req, void *ctx) {
    HTTPReply *reply = static_cast<HTTPReply *>(ctx);

    if (req == nullptr) {
        /**
         * If req is nullptr, it means an error occurred while connecting: the
         * error code will have been passed to http_error_cb.
         */
        reply->status = 0;
        return;
    }

    reply->status = evhttp_request_get_response_code(req);

    struct evbuffer *buf = evhttp_request_get_input_buffer(req);
    if (buf) {
        size_t size = evbuffer_get_length(buf);
        const char *data = (const char *)evbuffer_pullup(buf, size);
        if (data) reply->body = std::string(data, size);
        evbuffer_drain(buf, size);
    }
}

#if LIBEVENT_VERSION_NUMBER >= 0x02010300
static void http_error_cb(enum evhttp_request_error err, void *ctx) {
    HTTPReply *reply = static_cast<HTTPReply *>(ctx);
    reply->error = err;
}
#endif

/**
 * Class that handles the conversion from a command-line to a JSON-RPC request,
 * as well as converting back to a JSON object that can be shown as result.
 */
class BaseRequestHandler {
public:
    virtual UniValue PrepareRequest(const std::string &method,
                                    const std::vector<std::string> &args) = 0;
    virtual UniValue ProcessReply(const UniValue &batch_in) = 0;
};

/** Process getinfo requests */
class GetinfoRequestHandler : public BaseRequestHandler {
public:
    const int ID_NETWORKINFO = 0;
    const int ID_BLOCKCHAININFO = 1;
    const int ID_WALLETINFO = 2;

    /** Create a simulated `getinfo` request. */
    UniValue PrepareRequest(const std::string &method,
                            const std::vector<std::string> &args) override {
        UniValue result(UniValue::VARR);
        result.push_back(
            JSONRPCRequestObj("getnetworkinfo", NullUniValue, ID_NETWORKINFO));
        result.push_back(JSONRPCRequestObj("getblockchaininfo", NullUniValue,
                                           ID_BLOCKCHAININFO));
        result.push_back(
            JSONRPCRequestObj("getwalletinfo", NullUniValue, ID_WALLETINFO));
        return result;
    }

    /** Collect values from the batch and form a simulated `getinfo` reply. */
    UniValue ProcessReply(const UniValue &batch_in) override {
        UniValue result(UniValue::VOBJ);
        std::vector<UniValue> batch = JSONRPCProcessBatchReply(batch_in, 3);
        // Errors in getnetworkinfo() and getblockchaininfo() are fatal, pass
        // them on getwalletinfo() is allowed to fail in case there is no
        // wallet.
        if (!batch[ID_NETWORKINFO]["error"].isNull()) {
            return batch[ID_NETWORKINFO];
        }
        if (!batch[ID_BLOCKCHAININFO]["error"].isNull()) {
            return batch[ID_BLOCKCHAININFO];
        }
        result.pushKV("version", batch[ID_NETWORKINFO]["result"]["version"]);
        result.pushKV("protocolversion",
                      batch[ID_NETWORKINFO]["result"]["protocolversion"]);
        if (!batch[ID_WALLETINFO].isNull()) {
            result.pushKV("walletversion",
                          batch[ID_WALLETINFO]["result"]["walletversion"]);
            result.pushKV("balance", batch[ID_WALLETINFO]["result"]["balance"]);
        }
        result.pushKV("blocks", batch[ID_BLOCKCHAININFO]["result"]["blocks"]);
        result.pushKV("timeoffset",
                      batch[ID_NETWORKINFO]["result"]["timeoffset"]);
        result.pushKV("connections",
                      batch[ID_NETWORKINFO]["result"]["connections"]);
        result.pushKV("proxy",
                      batch[ID_NETWORKINFO]["result"]["networks"][0]["proxy"]);
        result.pushKV("difficulty",
                      batch[ID_BLOCKCHAININFO]["result"]["difficulty"]);
        result.pushKV(
            "testnet",
            UniValue(batch[ID_BLOCKCHAININFO]["result"]["chain"].get_str() ==
                     "test"));
        if (!batch[ID_WALLETINFO].isNull()) {
            result.pushKV("walletversion",
                          batch[ID_WALLETINFO]["result"]["walletversion"]);
            result.pushKV("balance", batch[ID_WALLETINFO]["result"]["balance"]);
            result.pushKV("keypoololdest",
                          batch[ID_WALLETINFO]["result"]["keypoololdest"]);
            result.pushKV("keypoolsize",
                          batch[ID_WALLETINFO]["result"]["keypoolsize"]);
            if (!batch[ID_WALLETINFO]["result"]["unlocked_until"].isNull()) {
                result.pushKV("unlocked_until",
                              batch[ID_WALLETINFO]["result"]["unlocked_until"]);
            }
            result.pushKV("paytxfee",
                          batch[ID_WALLETINFO]["result"]["paytxfee"]);
        }
        result.pushKV("relayfee", batch[ID_NETWORKINFO]["result"]["relayfee"]);
        result.pushKV("warnings", batch[ID_NETWORKINFO]["result"]["warnings"]);
        return JSONRPCReplyObj(result, NullUniValue, 1);
    }
};

/** Process default single requests */
class DefaultRequestHandler : public BaseRequestHandler {
public:
    UniValue PrepareRequest(const std::string &method,
                            const std::vector<std::string> &args) override {
        UniValue params;
        if (gArgs.GetBoolArg("-named", DEFAULT_NAMED)) {
            params = RPCConvertNamedValues(method, args);
        } else {
            params = RPCConvertValues(method, args);
        }
        return JSONRPCRequestObj(method, params, 1);
    }

    UniValue ProcessReply(const UniValue &reply) override {
        return reply.get_obj();
    }
};

static UniValue CallRPC(BaseRequestHandler *rh, const std::string &strMethod,
                        const std::vector<std::string> &args) {
    std::string host;
    // In preference order, we choose the following for the port:
    //     1. -rpcport
    //     2. port in -rpcconnect (ie following : in ipv4 or ]: in ipv6)
    //     3. default port for chain
    int port = BaseParams().RPCPort();
    SplitHostPort(gArgs.GetArg("-rpcconnect", DEFAULT_RPCCONNECT), port, host);
    port = gArgs.GetArg("-rpcport", port);

    // Obtain event base
    raii_event_base base = obtain_event_base();

    // Synchronously look up hostname
    raii_evhttp_connection evcon =
        obtain_evhttp_connection_base(base.get(), host, port);
    evhttp_connection_set_timeout(
        evcon.get(),
        gArgs.GetArg("-rpcclienttimeout", DEFAULT_HTTP_CLIENT_TIMEOUT));

    HTTPReply response;
    raii_evhttp_request req =
        obtain_evhttp_request(http_request_done, (void *)&response);
    if (req == nullptr) throw std::runtime_error("create http request failed");
#if LIBEVENT_VERSION_NUMBER >= 0x02010300
    evhttp_request_set_error_cb(req.get(), http_error_cb);
#endif

    // Get credentials
    std::string strRPCUserColonPass;
    if (gArgs.GetArg("-rpcpassword", "") == "") {
        // Try fall back to cookie-based authentication if no password is
        // provided
        if (!GetAuthCookie(&strRPCUserColonPass)) {
            throw std::runtime_error(strprintf(
                _("Could not locate RPC credentials. No authentication cookie "
                  "could be found, and RPC password is not set.  See "
                  "-rpcpassword and -stdinrpcpass.  Configuration file: (%s)"),
                GetConfigFile(gArgs.GetArg("-conf", BITCOIN_CONF_FILENAME))
                    .string()
                    .c_str()));
        }
    } else {
        strRPCUserColonPass = gArgs.GetArg("-rpcuser", "") + ":" +
                              gArgs.GetArg("-rpcpassword", "");
    }

    struct evkeyvalq *output_headers =
        evhttp_request_get_output_headers(req.get());
    assert(output_headers);
    evhttp_add_header(output_headers, "Host", host.c_str());
    evhttp_add_header(output_headers, "Connection", "close");
    evhttp_add_header(
        output_headers, "Authorization",
        (std::string("Basic ") + EncodeBase64(strRPCUserColonPass)).c_str());

    // Attach request data
    std::string strRequest = rh->PrepareRequest(strMethod, args).write() + "\n";
    struct evbuffer *output_buffer =
        evhttp_request_get_output_buffer(req.get());
    assert(output_buffer);
    evbuffer_add(output_buffer, strRequest.data(), strRequest.size());

    // check if we should use a special wallet endpoint
    std::string endpoint = "/";
    std::string walletName = gArgs.GetArg("-rpcwallet", "");
    if (!walletName.empty()) {
        char *encodedURI =
            evhttp_uriencode(walletName.c_str(), walletName.size(), false);
        if (encodedURI) {
            endpoint = "/wallet/" + std::string(encodedURI);
            free(encodedURI);
        } else {
            throw CConnectionFailed("uri-encode failed");
        }
    }
    int r = evhttp_make_request(evcon.get(), req.get(), EVHTTP_REQ_POST,
                                endpoint.c_str());
    // ownership moved to evcon in above call
    req.release();
    if (r != 0) {
        throw CConnectionFailed("send http request failed");
    }

    event_base_dispatch(base.get());

    if (response.status == 0) {
        throw CConnectionFailed(strprintf(
            "couldn't connect to server: %s (code %d)\n(make sure server is "
            "running and you are connecting to the correct RPC port)",
            http_errorstring(response.error), response.error));
    } else if (response.status == HTTP_UNAUTHORIZED) {
        throw std::runtime_error(
            "incorrect rpcuser or rpcpassword (authorization failed)");
    } else if (response.status >= 400 && response.status != HTTP_BAD_REQUEST &&
               response.status != HTTP_NOT_FOUND &&
               response.status != HTTP_INTERNAL_SERVER_ERROR) {
        throw std::runtime_error(
            strprintf("server returned HTTP error %d", response.status));
    } else if (response.body.empty()) {
        throw std::runtime_error("no response from server");
    }

    // Parse reply
    UniValue valReply(UniValue::VSTR);
    if (!valReply.read(response.body)) {
        throw std::runtime_error("couldn't parse reply from server");
    }
    const UniValue reply = rh->ProcessReply(valReply);
    if (reply.empty()) {
        throw std::runtime_error(
            "expected reply to have result, error and id properties");
    }

    return reply;
}

int CommandLineRPC(int argc, char *argv[]) {
    std::string strPrint;
    int nRet = 0;
    try {
        // Skip switches
        while (argc > 1 && IsSwitchChar(argv[1][0])) {
            argc--;
            argv++;
        }
        std::string rpcPass;
        if (gArgs.GetBoolArg("-stdinrpcpass", false)) {
            if (!std::getline(std::cin, rpcPass))
                throw std::runtime_error("-stdinrpcpass specified but failed "
                                         "to read from standard input");
            gArgs.ForceSetArg("-rpcpassword", rpcPass);
        }
        std::vector<std::string> args =
            std::vector<std::string>(&argv[1], &argv[argc]);
        if (gArgs.GetBoolArg("-stdin", false)) {
            // Read one arg per line from stdin and append
            std::string line;
            while (std::getline(std::cin, line)) {
                args.push_back(line);
            }
        }
        std::unique_ptr<BaseRequestHandler> rh;
        std::string method;
        if (gArgs.GetBoolArg("-getinfo", false)) {
            rh.reset(new GetinfoRequestHandler());
            method = "";
        } else {
            rh.reset(new DefaultRequestHandler());
            if (args.size() < 1) {
                throw std::runtime_error(
                    "too few parameters (need at least command)");
            }
            method = args[0];
            // Remove trailing method name from arguments vector
            args.erase(args.begin());
        }

        // Execute and handle connection failures with -rpcwait
        const bool fWait = gArgs.GetBoolArg("-rpcwait", false);
        do {
            try {
                const UniValue reply = CallRPC(rh.get(), method, args);

                // Parse reply
                const UniValue &result = find_value(reply, "result");
                const UniValue &error = find_value(reply, "error");

                if (!error.isNull()) {
                    // Error
                    int code = error["code"].get_int();
                    if (fWait && code == RPC_IN_WARMUP)
                        throw CConnectionFailed("server in warmup");
                    strPrint = "error: " + error.write();
                    nRet = abs(code);
                    if (error.isObject()) {
                        UniValue errCode = find_value(error, "code");
                        UniValue errMsg = find_value(error, "message");
                        strPrint =
                            errCode.isNull()
                                ? ""
                                : "error code: " + errCode.getValStr() + "\n";

                        if (errMsg.isStr()) {
                            strPrint += "error message:\n" + errMsg.get_str();
                        }

                        if (errCode.isNum() &&
                            errCode.get_int() == RPC_WALLET_NOT_SPECIFIED) {
                            strPrint += "\nTry adding "
                                        "\"-rpcwallet=<filename>\" option to "
                                        "bitcoin-cli command line.";
                        }
                    }
                } else {
                    // Result
                    if (result.isNull()) {
                        strPrint = "";
                    } else if (result.isStr()) {
                        strPrint = result.get_str();
                    } else {
                        strPrint = result.write(2);
                    }
                }
                // Connection succeeded, no need to retry.
                break;
            } catch (const CConnectionFailed &) {
                if (fWait) {
                    MilliSleep(1000);
                } else {
                    throw;
                }
            }
        } while (fWait);
    } catch (const thread_interrupted &) {
        throw;
    } catch (const std::exception &e) {
        strPrint = std::string("error: ") + e.what();
        nRet = EXIT_FAILURE;
    } catch (...) {
        PrintExceptionContinue(nullptr, "CommandLineRPC()");
        throw;
    }

    if (strPrint != "") {
        fprintf((nRet == 0 ? stdout : stderr), "%s\n", strPrint.c_str());
    }
    return nRet;
}

int main(int argc, char *argv[]) {
    SetupEnvironment();
    if (!SetupNetworking()) {
        fprintf(stderr, "Error: Initializing networking failed\n");
        return EXIT_FAILURE;
    }

    try {
        int ret = AppInitRPC(argc, argv);
        if (ret != CONTINUE_EXECUTION) {
            return ret;
        }
    } catch (const std::exception &e) {
        PrintExceptionContinue(&e, "AppInitRPC()");
        return EXIT_FAILURE;
    } catch (...) {
        PrintExceptionContinue(nullptr, "AppInitRPC()");
        return EXIT_FAILURE;
    }

    int ret = EXIT_FAILURE;
    try {
        ret = CommandLineRPC(argc, argv);
    } catch (const std::exception &e) {
        PrintExceptionContinue(&e, "CommandLineRPC()");
    } catch (...) {
        PrintExceptionContinue(nullptr, "CommandLineRPC()");
    }
    return ret;
}