rpc: Push down safe mode checks

This contains most of the changes of 10563 "remove safe mode", but doesn't
remove the safe mode yet, but put an `ObserveSafeMode()` check in
individual calls with okSafeMode=false.

This cleans up the ugly "okSafeMode" flag from the dispatch tables,
which is not a concern for the RPC server.

Extra-author: Wladimir J. van der Laan <laanwj@gmail.com>

9 files changed, 107 insertions, 84 deletions

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index 34f553f3b0..6e1af263dc 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -1532,35 +1532,35 @@ UniValue getchaintxstats(const JSONRPCRequest& request)
 }
 
 static const CRPCCommand commands[] =
-{ //  category              name                      actor (function)         okSafe argNames
-  //  --------------------- ------------------------  -----------------------  ------ ----------
-    { "blockchain",         "getblockchaininfo",      &getblockchaininfo,      true,  {} },
-    { "blockchain",         "getchaintxstats",        &getchaintxstats,        true,  {"nblocks", "blockhash"} },
-    { "blockchain",         "getbestblockhash",       &getbestblockhash,       true,  {} },
-    { "blockchain",         "getblockcount",          &getblockcount,          true,  {} },
-    { "blockchain",         "getblock",               &getblock,               true,  {"blockhash","verbosity|verbose"} },
-    { "blockchain",         "getblockhash",           &getblockhash,           true,  {"height"} },
-    { "blockchain",         "getblockheader",         &getblockheader,         true,  {"blockhash","verbose"} },
-    { "blockchain",         "getchaintips",           &getchaintips,           true,  {} },
-    { "blockchain",         "getdifficulty",          &getdifficulty,          true,  {} },
-    { "blockchain",         "getmempoolancestors",    &getmempoolancestors,    true,  {"txid","verbose"} },
-    { "blockchain",         "getmempooldescendants",  &getmempooldescendants,  true,  {"txid","verbose"} },
-    { "blockchain",         "getmempoolentry",        &getmempoolentry,        true,  {"txid"} },
-    { "blockchain",         "getmempoolinfo",         &getmempoolinfo,         true,  {} },
-    { "blockchain",         "getrawmempool",          &getrawmempool,          true,  {"verbose"} },
-    { "blockchain",         "gettxout",               &gettxout,               true,  {"txid","n","include_mempool"} },
-    { "blockchain",         "gettxoutsetinfo",        &gettxoutsetinfo,        true,  {} },
-    { "blockchain",         "pruneblockchain",        &pruneblockchain,        true,  {"height"} },
-    { "blockchain",         "verifychain",            &verifychain,            true,  {"checklevel","nblocks"} },
-
-    { "blockchain",         "preciousblock",          &preciousblock,          true,  {"blockhash"} },
+{ //  category              name                      actor (function)         argNames
+  //  --------------------- ------------------------  -----------------------  ----------
+    { "blockchain",         "getblockchaininfo",      &getblockchaininfo,      {} },
+    { "blockchain",         "getchaintxstats",        &getchaintxstats,        {"nblocks", "blockhash"} },
+    { "blockchain",         "getbestblockhash",       &getbestblockhash,       {} },
+    { "blockchain",         "getblockcount",          &getblockcount,          {} },
+    { "blockchain",         "getblock",               &getblock,               {"blockhash","verbosity|verbose"} },
+    { "blockchain",         "getblockhash",           &getblockhash,           {"height"} },
+    { "blockchain",         "getblockheader",         &getblockheader,         {"blockhash","verbose"} },
+    { "blockchain",         "getchaintips",           &getchaintips,           {} },
+    { "blockchain",         "getdifficulty",          &getdifficulty,          {} },
+    { "blockchain",         "getmempoolancestors",    &getmempoolancestors,    {"txid","verbose"} },
+    { "blockchain",         "getmempooldescendants",  &getmempooldescendants,  {"txid","verbose"} },
+    { "blockchain",         "getmempoolentry",        &getmempoolentry,        {"txid"} },
+    { "blockchain",         "getmempoolinfo",         &getmempoolinfo,         {} },
+    { "blockchain",         "getrawmempool",          &getrawmempool,          {"verbose"} },
+    { "blockchain",         "gettxout",               &gettxout,               {"txid","n","include_mempool"} },
+    { "blockchain",         "gettxoutsetinfo",        &gettxoutsetinfo,        {} },
+    { "blockchain",         "pruneblockchain",        &pruneblockchain,        {"height"} },
+    { "blockchain",         "verifychain",            &verifychain,            {"checklevel","nblocks"} },
+
+    { "blockchain",         "preciousblock",          &preciousblock,          {"blockhash"} },
 
     /* Not shown in help */
-    { "hidden",             "invalidateblock",        &invalidateblock,        true,  {"blockhash"} },
-    { "hidden",             "reconsiderblock",        &reconsiderblock,        true,  {"blockhash"} },
-    { "hidden",             "waitfornewblock",        &waitfornewblock,        true,  {"timeout"} },
-    { "hidden",             "waitforblock",           &waitforblock,           true,  {"blockhash","timeout"} },
-    { "hidden",             "waitforblockheight",     &waitforblockheight,     true,  {"height","timeout"} },
+    { "hidden",             "invalidateblock",        &invalidateblock,        {"blockhash"} },
+    { "hidden",             "reconsiderblock",        &reconsiderblock,        {"blockhash"} },
+    { "hidden",             "waitfornewblock",        &waitfornewblock,        {"timeout"} },
+    { "hidden",             "waitforblock",           &waitforblock,           {"blockhash","timeout"} },
+    { "hidden",             "waitforblockheight",     &waitforblockheight,     {"height","timeout"} },
 };
 
 void RegisterBlockchainRPCCommands(CRPCTable &t)
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 2692e59155..ca406ce448 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -967,20 +967,21 @@ UniValue estimaterawfee(const JSONRPCRequest& request)
 }
 
 static const CRPCCommand commands[] =
-{ //  category              name                      actor (function)         okSafeMode
+{ //  category              name                      actor (function)         argNames
   //  --------------------- ------------------------  -----------------------  ----------
-    { "mining",             "getnetworkhashps",       &getnetworkhashps,       true,  {"nblocks","height"} },
-    { "mining",             "getmininginfo",          &getmininginfo,          true,  {} },
-    { "mining",             "prioritisetransaction",  &prioritisetransaction,  true,  {"txid","dummy","fee_delta"} },
-    { "mining",             "getblocktemplate",       &getblocktemplate,       true,  {"template_request"} },
-    { "mining",             "submitblock",            &submitblock,            true,  {"hexdata","dummy"} },
+    { "mining",             "getnetworkhashps",       &getnetworkhashps,       {"nblocks","height"} },
+    { "mining",             "getmininginfo",          &getmininginfo,          {} },
+    { "mining",             "prioritisetransaction",  &prioritisetransaction,  {"txid","dummy","fee_delta"} },
+    { "mining",             "getblocktemplate",       &getblocktemplate,       {"template_request"} },
+    { "mining",             "submitblock",            &submitblock,            {"hexdata","dummy"} },
 
-    { "generating",         "generatetoaddress",      &generatetoaddress,      true,  {"nblocks","address","maxtries"} },
 
-    { "util",               "estimatefee",            &estimatefee,            true,  {"nblocks"} },
-    { "util",               "estimatesmartfee",       &estimatesmartfee,       true,  {"conf_target", "estimate_mode"} },
+    { "generating",         "generatetoaddress",      &generatetoaddress,      {"nblocks","address","maxtries"} },
 
-    { "hidden",             "estimaterawfee",         &estimaterawfee,         true,  {"conf_target", "threshold"} },
+    { "util",               "estimatefee",            &estimatefee,            {"nblocks"} },
+    { "util",               "estimatesmartfee",       &estimatesmartfee,       {"nblocks", "estimate_mode"} },
+
+    { "hidden",             "estimaterawfee",         &estimaterawfee,         {"conf_target", "threshold"} },
 };
 
 void RegisterMiningRPCCommands(CRPCTable &t)
diff --git a/src/rpc/misc.cpp b/src/rpc/misc.cpp
index a6af24f7e1..76eefabd29 100644
--- a/src/rpc/misc.cpp
+++ b/src/rpc/misc.cpp
@@ -649,20 +649,20 @@ UniValue echo(const JSONRPCRequest& request)
 }
 
 static const CRPCCommand commands[] =
-{ //  category              name                      actor (function)         okSafeMode
+{ //  category              name                      actor (function)         argNames
   //  --------------------- ------------------------  -----------------------  ----------
-    { "control",            "getinfo",                &getinfo,                true,  {} }, /* uses wallet if enabled */
-    { "control",            "getmemoryinfo",          &getmemoryinfo,          true,  {"mode"} },
-    { "util",               "validateaddress",        &validateaddress,        true,  {"address"} }, /* uses wallet if enabled */
-    { "util",               "createmultisig",         &createmultisig,         true,  {"nrequired","keys"} },
-    { "util",               "verifymessage",          &verifymessage,          true,  {"address","signature","message"} },
-    { "util",               "signmessagewithprivkey", &signmessagewithprivkey, true,  {"privkey","message"} },
+    { "control",            "getinfo",                &getinfo,                {} }, /* uses wallet if enabled */
+    { "control",            "getmemoryinfo",          &getmemoryinfo,          {"mode"} },
+    { "util",               "validateaddress",        &validateaddress,        {"address"} }, /* uses wallet if enabled */
+    { "util",               "createmultisig",         &createmultisig,         {"nrequired","keys"} },
+    { "util",               "verifymessage",          &verifymessage,          {"address","signature","message"} },
+    { "util",               "signmessagewithprivkey", &signmessagewithprivkey, {"privkey","message"} },
 
     /* Not shown in help */
-    { "hidden",             "setmocktime",            &setmocktime,            true,  {"timestamp"}},
-    { "hidden",             "echo",                   &echo,                   true,  {"arg0","arg1","arg2","arg3","arg4","arg5","arg6","arg7","arg8","arg9"}},
-    { "hidden",             "echojson",               &echo,                   true,  {"arg0","arg1","arg2","arg3","arg4","arg5","arg6","arg7","arg8","arg9"}},
-    { "hidden",             "logging",                &logging,                true,  {"include", "exclude"}},
+    { "hidden",             "setmocktime",            &setmocktime,            {"timestamp"}},
+    { "hidden",             "echo",                   &echo,                   {"arg0","arg1","arg2","arg3","arg4","arg5","arg6","arg7","arg8","arg9"}},
+    { "hidden",             "echojson",               &echo,                   {"arg0","arg1","arg2","arg3","arg4","arg5","arg6","arg7","arg8","arg9"}},
+    { "hidden",             "logging",                &logging,                {"include", "exclude"}},
 };
 
 void RegisterMiscRPCCommands(CRPCTable &t)
diff --git a/src/rpc/net.cpp b/src/rpc/net.cpp
index f19b968244..7faf216047 100644
--- a/src/rpc/net.cpp
+++ b/src/rpc/net.cpp
@@ -623,20 +623,20 @@ UniValue setnetworkactive(const JSONRPCRequest& request)
 }
 
 static const CRPCCommand commands[] =
-{ //  category              name                      actor (function)         okSafeMode
+{ //  category              name                      actor (function)         argNames
   //  --------------------- ------------------------  -----------------------  ----------
-    { "network",            "getconnectioncount",     &getconnectioncount,     true,  {} },
-    { "network",            "ping",                   &ping,                   true,  {} },
-    { "network",            "getpeerinfo",            &getpeerinfo,            true,  {} },
-    { "network",            "addnode",                &addnode,                true,  {"node","command"} },
-    { "network",            "disconnectnode",         &disconnectnode,         true,  {"address", "nodeid"} },
-    { "network",            "getaddednodeinfo",       &getaddednodeinfo,       true,  {"node"} },
-    { "network",            "getnettotals",           &getnettotals,           true,  {} },
-    { "network",            "getnetworkinfo",         &getnetworkinfo,         true,  {} },
-    { "network",            "setban",                 &setban,                 true,  {"subnet", "command", "bantime", "absolute"} },
-    { "network",            "listbanned",             &listbanned,             true,  {} },
-    { "network",            "clearbanned",            &clearbanned,            true,  {} },
-    { "network",            "setnetworkactive",       &setnetworkactive,       true,  {"state"} },
+    { "network",            "getconnectioncount",     &getconnectioncount,     {} },
+    { "network",            "ping",                   &ping,                   {} },
+    { "network",            "getpeerinfo",            &getpeerinfo,            {} },
+    { "network",            "addnode",                &addnode,                {"node","command"} },
+    { "network",            "disconnectnode",         &disconnectnode,         {"address", "nodeid"} },
+    { "network",            "getaddednodeinfo",       &getaddednodeinfo,       {"node"} },
+    { "network",            "getnettotals",           &getnettotals,           {} },
+    { "network",            "getnetworkinfo",         &getnetworkinfo,         {} },
+    { "network",            "setban",                 &setban,                 {"subnet", "command", "bantime", "absolute"} },
+    { "network",            "listbanned",             &listbanned,             {} },
+    { "network",            "clearbanned",            &clearbanned,            {} },
+    { "network",            "setnetworkactive",       &setnetworkactive,       {"state"} },
 };
 
 void RegisterNetRPCCommands(CRPCTable &t)
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 934576a391..27daefaf5a 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -16,6 +16,7 @@
 #include "policy/policy.h"
 #include "policy/rbf.h"
 #include "primitives/transaction.h"
+#include "rpc/safemode.h"
 #include "rpc/server.h"
 #include "script/script.h"
 #include "script/script_error.h"
@@ -703,6 +704,7 @@ UniValue signrawtransaction(const JSONRPCRequest& request)
             + HelpExampleRpc("signrawtransaction", "\"myhex\"")
         );
 
+    ObserveSafeMode();
 #ifdef ENABLE_WALLET
     LOCK2(cs_main, pwallet ? &pwallet->cs_wallet : nullptr);
 #else
@@ -908,6 +910,7 @@ UniValue sendrawtransaction(const JSONRPCRequest& request)
             + HelpExampleRpc("sendrawtransaction", "\"signedhex\"")
         );
 
+    ObserveSafeMode();
     LOCK(cs_main);
     RPCTypeCheck(request.params, {UniValue::VSTR, UniValue::VBOOL});
 
@@ -959,18 +962,18 @@ UniValue sendrawtransaction(const JSONRPCRequest& request)
 }
 
 static const CRPCCommand commands[] =
-{ //  category              name                      actor (function)         okSafeMode
+{ //  category              name                      actor (function)         argNames
   //  --------------------- ------------------------  -----------------------  ----------
-    { "rawtransactions",    "getrawtransaction",      &getrawtransaction,      true,  {"txid","verbose"} },
-    { "rawtransactions",    "createrawtransaction",   &createrawtransaction,   true,  {"inputs","outputs","locktime","replaceable"} },
-    { "rawtransactions",    "decoderawtransaction",   &decoderawtransaction,   true,  {"hexstring"} },
-    { "rawtransactions",    "decodescript",           &decodescript,           true,  {"hexstring"} },
-    { "rawtransactions",    "sendrawtransaction",     &sendrawtransaction,     false, {"hexstring","allowhighfees"} },
-    { "rawtransactions",    "combinerawtransaction",  &combinerawtransaction,  true,  {"txs"} },
-    { "rawtransactions",    "signrawtransaction",     &signrawtransaction,     false, {"hexstring","prevtxs","privkeys","sighashtype"} }, /* uses wallet if enabled */
-
-    { "blockchain",         "gettxoutproof",          &gettxoutproof,          true,  {"txids", "blockhash"} },
-    { "blockchain",         "verifytxoutproof",       &verifytxoutproof,       true,  {"proof"} },
+    { "rawtransactions",    "getrawtransaction",      &getrawtransaction,      {"txid","verbose"} },
+    { "rawtransactions",    "createrawtransaction",   &createrawtransaction,   {"inputs","outputs","locktime","replaceable"} },
+    { "rawtransactions",    "decoderawtransaction",   &decoderawtransaction,   {"hexstring"} },
+    { "rawtransactions",    "decodescript",           &decodescript,           {"hexstring"} },
+    { "rawtransactions",    "sendrawtransaction",     &sendrawtransaction,     {"hexstring","allowhighfees"} },
+    { "rawtransactions",    "combinerawtransaction",  &combinerawtransaction,  {"txs"} },
+    { "rawtransactions",    "signrawtransaction",     &signrawtransaction,     {"hexstring","prevtxs","privkeys","sighashtype"} }, /* uses wallet if enabled */
+
+    { "blockchain",         "gettxoutproof",          &gettxoutproof,          {"txids", "blockhash"} },
+    { "blockchain",         "verifytxoutproof",       &verifytxoutproof,       {"proof"} },
 };
 
 void RegisterRawTransactionRPCCommands(CRPCTable &t)
diff --git a/src/rpc/safemode.cpp b/src/rpc/safemode.cpp
new file mode 100644
index 0000000000..24770ad47f
--- /dev/null
+++ b/src/rpc/safemode.cpp
@@ -0,0 +1,14 @@
+#include "safemode.h"
+
+#include "rpc/protocol.h"
+#include "util.h"
+#include "warnings.h"
+
+void ObserveSafeMode()
+{
+    std::string warning = GetWarnings("rpc");
+    if (warning != "" && !gArgs.GetBoolArg("-disablesafemode", DEFAULT_DISABLE_SAFEMODE)) {
+        throw JSONRPCError(RPC_FORBIDDEN_BY_SAFE_MODE, std::string("Safe mode: ") + warning);
+    }
+}
+
diff --git a/src/rpc/safemode.h b/src/rpc/safemode.h
new file mode 100644
index 0000000000..8466d6b2f9
--- /dev/null
+++ b/src/rpc/safemode.h
@@ -0,0 +1,12 @@
+// Copyright (c) 2017 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_RPC_SAFEMODE_H
+#define BITCOIN_RPC_SAFEMODE_H
+
+static const bool DEFAULT_DISABLE_SAFEMODE = true;
+
+void ObserveSafeMode();
+
+#endif // BITCOIN_RPC_SAFEMODE_H
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 9ad8d228fa..428ab3b9b0 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -51,11 +51,6 @@ void RPCServer::OnStopped(std::function<void ()> slot)
     g_rpcSignals.Stopped.connect(slot);
 }
 
-void RPCServer::OnPreCommand(std::function<void (const CRPCCommand&)> slot)
-{
-    g_rpcSignals.PreCommand.connect(boost::bind(slot, _1));
-}
-
 void RPCTypeCheck(const UniValue& params,
                   const std::list<UniValue::VType>& typesExpected,
                   bool fAllowNull)
@@ -267,12 +262,12 @@ UniValue uptime(const JSONRPCRequest& jsonRequest)
  * Call Table
  */
 static const CRPCCommand vRPCCommands[] =
-{ //  category              name                      actor (function)         okSafe argNames
-  //  --------------------- ------------------------  -----------------------  ------ ----------
+{ //  category              name                      actor (function)         argNames
+  //  --------------------- ------------------------  -----------------------  ----------
     /* Overall control/query calls */
-    { "control",            "help",                   &help,                   true,  {"command"}  },
-    { "control",            "stop",                   &stop,                   true,  {}  },
-    { "control",            "uptime",                 &uptime,                 true,  {}  },
+    { "control",            "help",                   &help,                   {"command"}  },
+    { "control",            "stop",                   &stop,                   {}  },
+    { "control",            "uptime",                 &uptime,                 {}  },
 };
 
 CRPCTable::CRPCTable()
diff --git a/src/rpc/server.h b/src/rpc/server.h
index 89b1d169d5..777acbcb94 100644
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -25,7 +25,6 @@ namespace RPCServer
 {
     void OnStarted(std::function<void ()> slot);
     void OnStopped(std::function<void ()> slot);
-    void OnPreCommand(std::function<void (const CRPCCommand&)> slot);
 }
 
 /** Wrapper for UniValue::VType, which includes typeAny:
@@ -134,7 +133,6 @@ public:
     std::string category;
     std::string name;
     rpcfn_type actor;
-    bool okSafeMode;
     std::vector<std::string> argNames;
 };