forked from lix-project/lix
577ebeaefb
* Unify SSH code in SSHStore and LegacySSHStore. * Fix a race starting the SSH master. We now wait synchronously for the SSH master to finish starting. This prevents the SSH clients from starting their own connections. * Don't use a master if max-connections == 1. * Add a "max-connections" store parameter. * Add a "compress" store parameter.
94 lines
2.3 KiB
C++
94 lines
2.3 KiB
C++
#include "ssh.hh"
|
||
|
||
namespace nix {
|
||
|
||
std::unique_ptr<SSHMaster::Connection> SSHMaster::startCommand(const std::string & command)
|
||
{
|
||
startMaster();
|
||
|
||
Pipe in, out;
|
||
in.create();
|
||
out.create();
|
||
|
||
auto conn = std::make_unique<Connection>();
|
||
conn->sshPid = startProcess([&]() {
|
||
restoreSignals();
|
||
|
||
close(in.writeSide.get());
|
||
close(out.readSide.get());
|
||
|
||
if (dup2(in.readSide.get(), STDIN_FILENO) == -1)
|
||
throw SysError("duping over stdin");
|
||
if (dup2(out.writeSide.get(), STDOUT_FILENO) == -1)
|
||
throw SysError("duping over stdout");
|
||
|
||
Strings args = { "ssh", host.c_str(), "-x", "-a" };
|
||
if (!keyFile.empty())
|
||
args.insert(args.end(), {"-i", keyFile});
|
||
if (compress)
|
||
args.push_back("-C");
|
||
if (useMaster)
|
||
args.insert(args.end(), {"-S", socketPath});
|
||
args.push_back(command);
|
||
execvp(args.begin()->c_str(), stringsToCharPtrs(args).data());
|
||
|
||
throw SysError("executing ‘%s’ on ‘%s’", command, host);
|
||
});
|
||
|
||
|
||
in.readSide = -1;
|
||
out.writeSide = -1;
|
||
|
||
conn->out = std::move(out.readSide);
|
||
conn->in = std::move(in.writeSide);
|
||
|
||
return conn;
|
||
}
|
||
|
||
void SSHMaster::startMaster()
|
||
{
|
||
if (!useMaster || sshMaster != -1) return;
|
||
|
||
tmpDir = std::make_unique<AutoDelete>(createTempDir("", "nix", true, true, 0700));
|
||
|
||
socketPath = (Path) *tmpDir + "/ssh.sock";
|
||
|
||
Pipe out;
|
||
out.create();
|
||
|
||
sshMaster = startProcess([&]() {
|
||
restoreSignals();
|
||
|
||
close(out.readSide.get());
|
||
|
||
if (dup2(out.writeSide.get(), STDOUT_FILENO) == -1)
|
||
throw SysError("duping over stdout");
|
||
|
||
Strings args =
|
||
{ "ssh", host.c_str(), "-M", "-N", "-S", socketPath
|
||
, "-o", "LocalCommand=echo started"
|
||
, "-o", "PermitLocalCommand=yes"
|
||
};
|
||
if (!keyFile.empty())
|
||
args.insert(args.end(), {"-i", keyFile});
|
||
if (compress)
|
||
args.push_back("-C");
|
||
|
||
execvp(args.begin()->c_str(), stringsToCharPtrs(args).data());
|
||
|
||
throw SysError("starting SSH master");
|
||
});
|
||
|
||
out.writeSide = -1;
|
||
|
||
std::string reply;
|
||
try {
|
||
reply = readLine(out.readSide.get());
|
||
} catch (EndOfFile & e) { }
|
||
|
||
if (reply != "started")
|
||
throw Error("failed to start SSH master connection to ‘%s’", host);
|
||
}
|
||
|
||
}
|