/*
* InspIRCd -- Internet Relay Chat Daemon
*
* Copyright (C) 2021, 2024-2025 Sadie Powell <sadie@witchery.services>
*
* This file is part of InspIRCd. InspIRCd is free software: you can
* redistribute it and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "inspircd.h"
#include "main.h"
// The maximum line length in the 1205 protocol
#define COMPAT_LINE_LEN 510
namespace
{
size_t NextToken(const std::string& line, size_t start)
{
if (start == std::string::npos || start + 1 > line.length())
return std::string::npos;
return line.find(' ', start + 1);
}
}
void TreeSocket::WriteLine(const std::string& original_line)
{
if (LinkState != CONNECTED || proto_version == PROTO_NEWEST)
{
// Don't translate connections which have negotiated PROTO_NEWEST or
// where the protocol hasn't been negotiated yet.
WriteLineInternal(original_line);
return;
}
std::string line = original_line;
size_t cmdstart = 0;
if (line[0] == '@') // Skip the tags.
{
const auto tagend = NextToken(line, cmdstart);
auto tagsep = '@';
std::string newtags;
irc::sepstream ss(line.substr(cmdstart + 1, tagend - cmdstart - 1), ';');
for (std::string tag; ss.GetToken(tag); )
{
// Skip server tags.
if (tag[0] != '~')
{
newtags.push_back(tagsep);
newtags.append(tag);
tagsep = ';';
}
}
if (!newtags.empty())
newtags.push_back(' ');
line.replace(cmdstart, tagend - cmdstart + 1, newtags);
cmdstart = NextToken(line, cmdstart);
if (cmdstart != std::string::npos)
cmdstart++;
}
size_t sidstart = std::string::npos;
if (line[cmdstart] == ':') // Skip the prefix.
{
sidstart = cmdstart + 1;
cmdstart = NextToken(line, cmdstart);
if (cmdstart != std::string::npos)
cmdstart++;
}
// Find the end of the command.
size_t cmdend = NextToken(line, cmdstart);
if (cmdend == std::string::npos)
cmdend = line.size() - 1;
std::string command(line, cmdstart, cmdend - cmdstart);
if (proto_version == PROTO_INSPIRCD_3)
{
if (irc::equals(command, "ENCAP"))
{
// :<sid> ENCAP <server> <real-command>
auto serverend = NextToken(line, cmdend);
auto actualcmdend = NextToken(line, serverend);
if (actualcmdend != std::string::npos)
{
std::string realcommand(line, serverend + 1, actualcmdend - serverend - 1);
if (irc::equals(realcommand, "SASL"))
{
auto suidend = NextToken(line, actualcmdend);
auto tuidend = NextToken(line, suidend);
auto flagend = NextToken(line, tuidend);
if (flagend != std::string::npos)
{
std::string flag(line, tuidend + 1, flagend - tuidend - 1);
if (irc::equals(flag, "S"))
{
// SASL <uid> <uid> S <mech> <fp> [<fp>]+
auto mechend = NextToken(line, flagend);
auto fpend = NextToken(line, mechend);
if (fpend != std::string::npos)
line.erase(fpend); // Multiple fingerprints in ssl_cert was introduced in PROTO_INSPIRCD_4; drop it.
}
}
}
}
}
else if (irc::equals(command, "FHOST") || irc::equals(command, "FIDENT"))
{
// FIDENT/FHOST has two parameters in v4; drop the real username/hostname.
// :<sid> FIDENT|FHOST <display|*> <real|*>
size_t displayend = NextToken(line, cmdend);
if (displayend != std::string::npos)
{
if ((displayend - cmdend) == 2 && line[displayend - 1] == '*')
return; // FIDENT/FHOST is only changing the real username/hostname; drop.
// Trim the rest of the line.
line.erase(displayend);
}
}
else if (irc::equals(command, "FJOIN"))
{
// FJOIN has no length limit in v4
// :<sid> FJOIN <chan> <TS> <modes> :[<member> [<member> ...]]
const auto chanend = NextToken(line, cmdend);
const auto chantsend = NextToken(line, chanend);
const auto modesend = NextToken(line, chantsend);
if (modesend != std::string::npos)
{
const auto maxlinelen = cmdstart + COMPAT_LINE_LEN;
while (line.length() > maxlinelen)
{
auto lastpos = line.rfind(' ', maxlinelen);
if (lastpos != std::string::npos)
{
WriteLineInternal(line.substr(0, lastpos));
line.erase(modesend, lastpos - modesend);
}
}
}
}
else if (irc::equals(command, "LMODE"))
{
// LMODE is new in v4; downgrade to FMODE.
// :<sid> LMODE <chan> <chants> <modechr> [<mask> <setts> <setter>]+
auto chanend = NextToken(line, cmdend);
auto chantsend = NextToken(line, chanend);
auto modechrend = NextToken(line, chantsend);
if (modechrend != std::string::npos)
{
// This should only be one character but its best to be sure...
auto modechr = line.substr(chantsend + 1, modechrend - chantsend - 1);
auto prevend = modechrend;
// Build a new mode and parameter list.
std::string modelist = "+";
std::string paramlist;
while (prevend != std::string::npos)
{
// We drop the setts and setter for the old protocol.
auto maskend = NextToken(line, prevend);
auto settsend = NextToken(line, maskend);
if (settsend != std::string::npos)
{
modelist.append(modechr);
paramlist.append(" ").append(line.substr(prevend + 1, maskend - prevend - 1));
}
prevend = NextToken(line, settsend);
}
// Replace the mode tuples with a list of mode values.
line.replace(modechrend, line.length() - modechrend, paramlist);
// Replace the mode character with a list of +modes
line.replace(chantsend + 1, modechrend - chantsend - 1, modelist);
// Replace LMODE with FMODE.
line.replace(cmdstart, 5, "FMODE");
}
}
else if (irc::equals(command, "METADATA"))
{
// :<sid> METADATA <uuid|chan|*|@> <name> :<value>
size_t targetend = NextToken(line, cmdend);
size_t nameend = NextToken(line, targetend);
size_t flagend = NextToken(line, nameend);
if (flagend != std::string::npos)
{
std::string extname(line, targetend + 1, nameend - targetend - 1);
if (irc::equals(extname, "ssl_cert"))
{
// Check we have the "e" flag (no error).
if (line.find('e', nameend + 1) < flagend)
{
size_t fpend = NextToken(line, flagend);
if (fpend != std::string::npos)
{
size_t commapos = line.find(',', flagend + 1);
if (commapos < fpend)
{
// Multiple fingerprints in ssl_cert was introduced in PROTO_INSPIRCD_4; drop it.
line.erase(commapos, fpend - commapos);
}
}
}
}
}
}
else if (irc::equals(command, "SINFO"))
{
// :<sid> SINFO <key> :<value>
auto keyend = NextToken(line, cmdend);
if (keyend != std::string::npos && sidstart != std::string::npos)
{
auto skey = line.substr(cmdend + 1, keyend - cmdend - 1);
if (irc::equals(skey, "customversion"))
return;
else if (irc::equals(skey, "rawbranch"))
{
// InspIRCd-4. testnet.inspircd.org :Test
auto* sid = Utils->FindServerID(line.substr(sidstart, cmdstart - sidstart - 1));
if (sid)
{
line.replace(cmdend + 1, keyend - cmdend - 1, "version");
line.append(INSP_FORMAT(". {} :{}", sid->GetPublicName(), sid->GetDesc()));
}
}
else if (irc::equals(skey, "rawversion"))
{
// InspIRCd-4.0.0-a10. sadie.testnet.inspircd.org :[597] Test
auto* sid = Utils->FindServerID(line.substr(sidstart, cmdstart - sidstart - 1));
if (sid)
{
line.replace(cmdend + 1, keyend - cmdend - 1, "fullversion");
line.append(INSP_FORMAT(". {} :[{}] {}", sid->GetName(), sid->GetId(), sid->GetDesc()));
}
}
}
}
else if (irc::equals(command, "SQUERY"))
{
// SQUERY was introduced in PROTO_INSPIRCD_4; convert to PRIVMSG.
line.replace(cmdstart, 6, "PRIVMSG");
}
else if (irc::equals(command, "UID"))
{
// :<sid> UID <uuid> <nickchanged> <nick> <host> <dhost> <user> <duser> <ip.string> <signon> <modes> [<modepara>] :<real>
// ^^^^^^ New in 1206
size_t uuidend = NextToken(line, cmdend);
size_t nickchangedend = NextToken(line, uuidend);
size_t nickend = NextToken(line, nickchangedend);
size_t hostend = NextToken(line, nickend);
size_t dhostend = NextToken(line, hostend);
size_t userend = NextToken(line, dhostend);
if (userend != std::string::npos)
line.erase(dhostend, userend - dhostend);
}
}
WriteLineInternal(line);
}
bool TreeSocket::PreProcessOldProtocolMessage(User*& who, std::string& cmd, CommandBase::Params& params)
{
if (irc::equals(cmd, "FHOST") || irc::equals(cmd, "FIDENT"))
{
if (params.size() < 2)
params.push_back("*");
}
else if (irc::equals(cmd, "SVSJOIN") || irc::equals(cmd, "SVSNICK") || irc::equals(cmd, "SVSPART"))
{
if (params.empty())
return false; // Malformed.
auto* target = ServerInstance->Users.FindUUID(params[0]);
if (!target)
return false; // User gone.
params.insert(params.begin(), { target->uuid.substr(0, 3), cmd });
cmd = "ENCAP";
}
else if (irc::equals(cmd, "UID"))
{
if (params.size() < 6)
return false; // Malformed.
// :<sid> UID <uuid> <nickchanged> <nick> <host> <dhost> <user> <duser> <ip.string> <signon> <modes> [<modepara>] :<real>
// ^^^^^^ New in 1206
params.insert(params.begin() + 5, params[5]);
}
return true;
}
