Pull uacomment in from upstream

Used primarialy (for now) in node identification for upcoming regtest
scripting.

Signed-off-by: observerdev <dev@obsr.org>

src/init.cpp

@@ -469,6 +469,7 @@ std::string HelpMessage(HelpMessageMode mode)
 #endif
 
     strUsage += HelpMessageGroup(_("Debugging/Testing options:"));
+    strUsage += HelpMessageOpt("-uacomment=<cmt>", _("Append comment to the user agent string"));
     if (GetBoolArg("-help-debug", false)) {
         strUsage += HelpMessageOpt("-checkblockindex", strprintf("Do a full consistency check for mapBlockIndex, setBlockIndexCandidates, chainActive and mapBlocksUnlinked occasionally. Also sets -checkmempool (default: %u)", Params(CBaseChainParams::MAIN).DefaultConsistencyChecks()));
         strUsage += HelpMessageOpt("-checkmempool=<n>", strprintf("Run checks every <n> transactions (default: %u)", Params(CBaseChainParams::MAIN).DefaultConsistencyChecks()));
@@ -1215,6 +1216,21 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
 
     RegisterNodeSignals(GetNodeSignals());
 
+    // sanitize comments per BIP-0014, format user agent and check total size
+    std::vector<std::string> uacomments;
+    for (const std::string& cmt : mapMultiArgs["-uacomment"]) {
+        if (cmt != SanitizeString(cmt, SAFE_CHARS_UA_COMMENT))
+            return InitError(strprintf(_("User Agent comment (%s) contains unsafe characters."), cmt));
+        uacomments.push_back(cmt);
+    }
+
+    // format user agent, check total size
+    strSubVersion = FormatSubVersion(CLIENT_NAME, CLIENT_VERSION, uacomments);
+    if (strSubVersion.size() > MAX_SUBVERSION_LENGTH) {
+        return InitError(strprintf(_("Total length of network version string (%i) exceeds maximum length (%i). Reduce the number or size of uacomments."),
+            strSubVersion.size(), MAX_SUBVERSION_LENGTH));
+    }
+
     if (mapArgs.count("-onlynet")) {
         std::set<enum Network> nets;
         BOOST_FOREACH (std::string snet, mapMultiArgs["-onlynet"]) {

src/main.cpp

@@ -5531,7 +5531,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
         if (!vRecv.empty())
             vRecv >> addrFrom >> nNonce;
         if (!vRecv.empty()) {
-            vRecv >> LIMITED_STRING(pfrom->strSubVer, 256);
+            vRecv >> LIMITED_STRING(pfrom->strSubVer, MAX_SUBVERSION_LENGTH);
             pfrom->cleanSubVer = SanitizeString(pfrom->strSubVer);
         }
         if (!vRecv.empty())

src/net.cpp

@@ -86,6 +86,7 @@ static std::vector<ListenSocket> vhListenSocket;
 CAddrMan addrman;
 int nMaxConnections = 125;
 bool fAddressesInitialized = false;
+std::string strSubVersion;
 
 vector<CNode*> vNodes;
 CCriticalSection cs_vNodes;
@@ -484,7 +485,7 @@ void CNode::PushVersion()
     else
         LogPrint("net", "send version message: version %d, blocks=%d, us=%s, peer=%d\n", PROTOCOL_VERSION, nBestHeight, addrMe.ToString(), id);
     PushMessage("version", PROTOCOL_VERSION, nLocalServices, nTime, addrYou, addrMe,
-        nLocalHostNonce, FormatSubVersion(CLIENT_NAME, CLIENT_VERSION, std::vector<string>()), nBestHeight, true);
+        nLocalHostNonce, strSubVersion, nBestHeight, true);
 }
 
 
@@ -1725,7 +1726,7 @@ void StartNode(boost::thread_group& threadGroup, CScheduler& scheduler)
     CNode::SetBannedSetDirty(false); //no need to write down just read or nonexistent data
     CNode::SweepBanned(); //sweap out unused entries
 
-    // Initialize random numbers. Even when rand() is only usable for trivial use-cases most nodes should have a different 
+    // Initialize random numbers. Even when rand() is only usable for trivial use-cases most nodes should have a different
     // seed after all the file-IO done at this point. Should be good enough even when nodes are started via scripts.
     srand(time(NULL));
 

src/net.h

@@ -52,6 +52,8 @@ static const unsigned int MAX_INV_SZ = 50000;
 static const unsigned int MAX_ADDR_TO_SEND = 1000;
 /** Maximum length of incoming protocol messages (no message over 2 MiB is currently acceptable). */
 static const unsigned int MAX_PROTOCOL_MESSAGE_LENGTH = 2 * 1024 * 1024;
+/** Maximum length of strSubVer in `version` message */
+static const unsigned int MAX_SUBVERSION_LENGTH = 256;
 /** -listen default */
 static const bool DEFAULT_LISTEN = true;
 /** -upnp default */
@@ -143,6 +145,9 @@ extern CCriticalSection cs_vAddedNodes;
 extern NodeId nLastNodeId;
 extern CCriticalSection cs_nLastNodeId;
 
+/** Subversion as sent to the P2P network in `version` messages */
+extern std::string strSubVersion;
+
 struct LocalServiceInfo {
     int nScore;
     int nPort;

src/rpc/net.cpp

@@ -430,8 +430,7 @@ UniValue getnetworkinfo(const UniValue& params, bool fHelp)
 
     UniValue obj(UniValue::VOBJ);
     obj.push_back(Pair("version", CLIENT_VERSION));
-    obj.push_back(Pair("subversion",
-        FormatSubVersion(CLIENT_NAME, CLIENT_VERSION, std::vector<string>())));
+    obj.push_back(Pair("subversion",    strSubVersion));
     obj.push_back(Pair("protocolversion", PROTOCOL_VERSION));
     obj.push_back(Pair("localservices", strprintf("%016x", nLocalServices)));
     obj.push_back(Pair("timeoffset", GetTimeOffset()));

src/utilstrencodings.cpp

@@ -22,16 +22,21 @@
 
 using namespace std;
 
-string SanitizeString(const string& str)
+static const std::string CHARS_ALPHA_NUM = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+
+static const std::string SAFE_CHARS[] =
 {
-    /**
-     * safeChars chosen to allow simple messages/URLs/email addresses, but avoid anything
-     * even possibly remotely dangerous like & or >
-     */
-    static string safeChars("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890 .,;_-/:?@()");
-    string strResult;
-    for (std::string::size_type i = 0; i < str.size(); i++) {
-        if (safeChars.find(str[i]) != std::string::npos)
+    CHARS_ALPHA_NUM + " .,;-_/:?@()", // SAFE_CHARS_DEFAULT
+    CHARS_ALPHA_NUM + " .,;-_?@", // SAFE_CHARS_UA_COMMENT
+    CHARS_ALPHA_NUM + ".-_", // SAFE_CHARS_FILENAME
+};
+
+std::string SanitizeString(const std::string& str, int rule)
+{
+    std::string strResult;
+    for (std::string::size_type i = 0; i < str.size(); i++)
+    {
+        if (SAFE_CHARS[rule].find(str[i]) != std::string::npos)
             strResult.push_back(str[i]);
     }
     return strResult;

src/utilstrencodings.h

@@ -25,7 +25,22 @@
 /** This is needed because the foreach macro can't get over the comma in pair<t1, t2> */
 #define PAIRTYPE(t1, t2) std::pair<t1, t2>
 
-std::string SanitizeString(const std::string& str);
+/** Used by SanitizeString() */
+enum SafeChars
+{
+    SAFE_CHARS_DEFAULT, //!< The full set of allowed chars
+    SAFE_CHARS_UA_COMMENT, //!< BIP-0014 subset
+    SAFE_CHARS_FILENAME, //!< Chars allowed in filenames
+};
+
+/**
+* Remove unsafe chars. Safe chars chosen to allow simple messages/URLs/email
+* addresses, but avoid anything even possibly remotely dangerous like & or >
+* @param[in] str    The string to sanitize
+* @param[in] rule   The set of safe chars to choose (default: least restrictive)
+* @return           A new string without unsafe chars
+*/
+std::string SanitizeString(const std::string& str, int rule = SAFE_CHARS_DEFAULT);
 std::vector<unsigned char> ParseHex(const char* psz);
 std::vector<unsigned char> ParseHex(const std::string& str);
 signed char HexDigit(char c);