forked from lix-project/lix
875 lines
24 KiB
C++
875 lines
24 KiB
C++
#include "shared.hh"
|
||
#include "local-store.hh"
|
||
#include "util.hh"
|
||
#include "serialise.hh"
|
||
#include "worker-protocol.hh"
|
||
#include "archive.hh"
|
||
#include "affinity.hh"
|
||
#include "globals.hh"
|
||
#include "monitor-fd.hh"
|
||
#include "derivations.hh"
|
||
|
||
#include <algorithm>
|
||
|
||
#include <cstring>
|
||
#include <unistd.h>
|
||
#include <signal.h>
|
||
#include <sys/types.h>
|
||
#include <sys/wait.h>
|
||
#include <sys/stat.h>
|
||
#include <sys/socket.h>
|
||
#include <sys/un.h>
|
||
#include <errno.h>
|
||
#include <pwd.h>
|
||
#include <grp.h>
|
||
|
||
#if __APPLE__ || __FreeBSD__
|
||
#include <sys/ucred.h>
|
||
#endif
|
||
|
||
using namespace nix;
|
||
|
||
|
||
static FdSource from(STDIN_FILENO);
|
||
static FdSink to(STDOUT_FILENO);
|
||
|
||
bool canSendStderr;
|
||
|
||
|
||
/* This function is called anytime we want to write something to
|
||
stderr. If we're in a state where the protocol allows it (i.e.,
|
||
when canSendStderr), send the message to the client over the
|
||
socket. */
|
||
static void tunnelStderr(const unsigned char * buf, size_t count)
|
||
{
|
||
if (canSendStderr) {
|
||
try {
|
||
to << STDERR_NEXT;
|
||
writeString(buf, count, to);
|
||
to.flush();
|
||
} catch (...) {
|
||
/* Write failed; that means that the other side is
|
||
gone. */
|
||
canSendStderr = false;
|
||
throw;
|
||
}
|
||
} else
|
||
writeFull(STDERR_FILENO, buf, count);
|
||
}
|
||
|
||
|
||
/* startWork() means that we're starting an operation for which we
|
||
want to send out stderr to the client. */
|
||
static void startWork()
|
||
{
|
||
canSendStderr = true;
|
||
}
|
||
|
||
|
||
/* stopWork() means that we're done; stop sending stderr to the
|
||
client. */
|
||
static void stopWork(bool success = true, const string & msg = "", unsigned int status = 0)
|
||
{
|
||
canSendStderr = false;
|
||
|
||
if (success)
|
||
to << STDERR_LAST;
|
||
else {
|
||
to << STDERR_ERROR << msg;
|
||
if (status != 0) to << status;
|
||
}
|
||
}
|
||
|
||
|
||
struct TunnelSink : Sink
|
||
{
|
||
Sink & to;
|
||
TunnelSink(Sink & to) : to(to) { }
|
||
virtual void operator () (const unsigned char * data, size_t len)
|
||
{
|
||
to << STDERR_WRITE;
|
||
writeString(data, len, to);
|
||
}
|
||
};
|
||
|
||
|
||
struct TunnelSource : BufferedSource
|
||
{
|
||
Source & from;
|
||
TunnelSource(Source & from) : from(from) { }
|
||
size_t readUnbuffered(unsigned char * data, size_t len)
|
||
{
|
||
to << STDERR_READ << len;
|
||
to.flush();
|
||
size_t n = readString(data, len, from);
|
||
if (n == 0) throw EndOfFile("unexpected end-of-file");
|
||
return n;
|
||
}
|
||
};
|
||
|
||
|
||
/* If the NAR archive contains a single file at top-level, then save
|
||
the contents of the file to `s'. Otherwise barf. */
|
||
struct RetrieveRegularNARSink : ParseSink
|
||
{
|
||
bool regular;
|
||
string s;
|
||
|
||
RetrieveRegularNARSink() : regular(true) { }
|
||
|
||
void createDirectory(const Path & path)
|
||
{
|
||
regular = false;
|
||
}
|
||
|
||
void receiveContents(unsigned char * data, unsigned int len)
|
||
{
|
||
s.append((const char *) data, len);
|
||
}
|
||
|
||
void createSymlink(const Path & path, const string & target)
|
||
{
|
||
regular = false;
|
||
}
|
||
};
|
||
|
||
|
||
/* Adapter class of a Source that saves all data read to `s'. */
|
||
struct SavingSourceAdapter : Source
|
||
{
|
||
Source & orig;
|
||
string s;
|
||
SavingSourceAdapter(Source & orig) : orig(orig) { }
|
||
size_t read(unsigned char * data, size_t len)
|
||
{
|
||
size_t n = orig.read(data, len);
|
||
s.append((const char *) data, n);
|
||
return n;
|
||
}
|
||
};
|
||
|
||
|
||
static void performOp(bool trusted, unsigned int clientVersion,
|
||
Source & from, Sink & to, unsigned int op)
|
||
{
|
||
switch (op) {
|
||
|
||
case wopIsValidPath: {
|
||
/* 'readStorePath' could raise an error leading to the connection
|
||
being closed. To be able to recover from an invalid path error,
|
||
call 'startWork' early, and do 'assertStorePath' afterwards so
|
||
that the 'Error' exception handler doesn't close the
|
||
connection. */
|
||
Path path = readString(from);
|
||
startWork();
|
||
assertStorePath(path);
|
||
bool result = store->isValidPath(path);
|
||
stopWork();
|
||
to << result;
|
||
break;
|
||
}
|
||
|
||
case wopQueryValidPaths: {
|
||
PathSet paths = readStorePaths<PathSet>(from);
|
||
startWork();
|
||
PathSet res = store->queryValidPaths(paths);
|
||
stopWork();
|
||
to << res;
|
||
break;
|
||
}
|
||
|
||
case wopHasSubstitutes: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
PathSet res = store->querySubstitutablePaths(singleton<PathSet>(path));
|
||
stopWork();
|
||
to << (res.find(path) != res.end());
|
||
break;
|
||
}
|
||
|
||
case wopQuerySubstitutablePaths: {
|
||
PathSet paths = readStorePaths<PathSet>(from);
|
||
startWork();
|
||
PathSet res = store->querySubstitutablePaths(paths);
|
||
stopWork();
|
||
to << res;
|
||
break;
|
||
}
|
||
|
||
case wopQueryPathHash: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
Hash hash = store->queryPathHash(path);
|
||
stopWork();
|
||
to << printHash(hash);
|
||
break;
|
||
}
|
||
|
||
case wopQueryReferences:
|
||
case wopQueryReferrers:
|
||
case wopQueryValidDerivers:
|
||
case wopQueryDerivationOutputs: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
PathSet paths;
|
||
if (op == wopQueryReferences)
|
||
store->queryReferences(path, paths);
|
||
else if (op == wopQueryReferrers)
|
||
store->queryReferrers(path, paths);
|
||
else if (op == wopQueryValidDerivers)
|
||
paths = store->queryValidDerivers(path);
|
||
else paths = store->queryDerivationOutputs(path);
|
||
stopWork();
|
||
to << paths;
|
||
break;
|
||
}
|
||
|
||
case wopQueryDerivationOutputNames: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
StringSet names;
|
||
names = store->queryDerivationOutputNames(path);
|
||
stopWork();
|
||
to << names;
|
||
break;
|
||
}
|
||
|
||
case wopQueryDeriver: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
Path deriver = store->queryDeriver(path);
|
||
stopWork();
|
||
to << deriver;
|
||
break;
|
||
}
|
||
|
||
case wopQueryPathFromHashPart: {
|
||
string hashPart = readString(from);
|
||
startWork();
|
||
Path path = store->queryPathFromHashPart(hashPart);
|
||
stopWork();
|
||
to << path;
|
||
break;
|
||
}
|
||
|
||
case wopAddToStore: {
|
||
string baseName = readString(from);
|
||
bool fixed = readInt(from) == 1; /* obsolete */
|
||
bool recursive = readInt(from) == 1;
|
||
string s = readString(from);
|
||
/* Compatibility hack. */
|
||
if (!fixed) {
|
||
s = "sha256";
|
||
recursive = true;
|
||
}
|
||
HashType hashAlgo = parseHashType(s);
|
||
|
||
SavingSourceAdapter savedNAR(from);
|
||
RetrieveRegularNARSink savedRegular;
|
||
|
||
if (recursive) {
|
||
/* Get the entire NAR dump from the client and save it to
|
||
a string so that we can pass it to
|
||
addToStoreFromDump(). */
|
||
ParseSink sink; /* null sink; just parse the NAR */
|
||
parseDump(sink, savedNAR);
|
||
} else
|
||
parseDump(savedRegular, from);
|
||
|
||
startWork();
|
||
if (!savedRegular.regular) throw Error("regular file expected");
|
||
Path path = dynamic_cast<LocalStore *>(store.get())
|
||
->addToStoreFromDump(recursive ? savedNAR.s : savedRegular.s, baseName, recursive, hashAlgo);
|
||
stopWork();
|
||
|
||
to << path;
|
||
break;
|
||
}
|
||
|
||
case wopAddTextToStore: {
|
||
string suffix = readString(from);
|
||
string s = readString(from);
|
||
PathSet refs = readStorePaths<PathSet>(from);
|
||
startWork();
|
||
Path path = store->addTextToStore(suffix, s, refs);
|
||
stopWork();
|
||
to << path;
|
||
break;
|
||
}
|
||
|
||
case wopExportPath: {
|
||
Path path = readStorePath(from);
|
||
bool sign = readInt(from) == 1;
|
||
startWork();
|
||
TunnelSink sink(to);
|
||
store->exportPath(path, sign, sink);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopImportPaths: {
|
||
startWork();
|
||
TunnelSource source(from);
|
||
Paths paths = store->importPaths(!trusted, source);
|
||
stopWork();
|
||
to << paths;
|
||
break;
|
||
}
|
||
|
||
case wopBuildPaths: {
|
||
PathSet drvs = readStorePaths<PathSet>(from);
|
||
startWork();
|
||
store->buildPaths(drvs);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopBuildDerivation: {
|
||
Path drvPath = readStorePath(from);
|
||
BasicDerivation drv;
|
||
from >> drv;
|
||
BuildMode buildMode = (BuildMode) readInt(from);
|
||
startWork();
|
||
if (!trusted)
|
||
throw Error("you are not privileged to build derivations");
|
||
auto res = store->buildDerivation(drvPath, drv, buildMode);
|
||
stopWork();
|
||
to << res.status << res.errorMsg;
|
||
break;
|
||
}
|
||
|
||
case wopEnsurePath: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
store->ensurePath(path);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopAddTempRoot: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
store->addTempRoot(path);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopAddIndirectRoot: {
|
||
Path path = absPath(readString(from));
|
||
startWork();
|
||
store->addIndirectRoot(path);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopSyncWithGC: {
|
||
startWork();
|
||
store->syncWithGC();
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopFindRoots: {
|
||
startWork();
|
||
Roots roots = store->findRoots();
|
||
stopWork();
|
||
to << roots.size();
|
||
for (auto & i : roots)
|
||
to << i.first << i.second;
|
||
break;
|
||
}
|
||
|
||
case wopCollectGarbage: {
|
||
GCOptions options;
|
||
options.action = (GCOptions::GCAction) readInt(from);
|
||
options.pathsToDelete = readStorePaths<PathSet>(from);
|
||
options.ignoreLiveness = readInt(from);
|
||
options.maxFreed = readLongLong(from);
|
||
readInt(from); // obsolete field
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 5) {
|
||
/* removed options */
|
||
readInt(from);
|
||
readInt(from);
|
||
}
|
||
|
||
GCResults results;
|
||
|
||
startWork();
|
||
if (options.ignoreLiveness)
|
||
throw Error("you are not allowed to ignore liveness");
|
||
store->collectGarbage(options, results);
|
||
stopWork();
|
||
|
||
to << results.paths << results.bytesFreed << 0 /* obsolete */;
|
||
|
||
break;
|
||
}
|
||
|
||
case wopSetOptions: {
|
||
settings.keepFailed = readInt(from) != 0;
|
||
settings.keepGoing = readInt(from) != 0;
|
||
settings.set("build-fallback", readInt(from) ? "true" : "false");
|
||
verbosity = (Verbosity) readInt(from);
|
||
settings.set("build-max-jobs", int2String(readInt(from)));
|
||
settings.set("build-max-silent-time", int2String(readInt(from)));
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 2)
|
||
settings.useBuildHook = readInt(from) != 0;
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 4) {
|
||
settings.buildVerbosity = (Verbosity) readInt(from);
|
||
logType = (LogType) readInt(from);
|
||
settings.printBuildTrace = readInt(from) != 0;
|
||
}
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 6)
|
||
settings.set("build-cores", int2String(readInt(from)));
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 10)
|
||
settings.set("build-use-substitutes", readInt(from) ? "true" : "false");
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 12) {
|
||
unsigned int n = readInt(from);
|
||
for (unsigned int i = 0; i < n; i++) {
|
||
string name = readString(from);
|
||
string value = readString(from);
|
||
if (name == "build-timeout" || name == "use-ssh-substituter")
|
||
settings.set(name, value);
|
||
else
|
||
settings.set(trusted ? name : "untrusted-" + name, value);
|
||
}
|
||
}
|
||
settings.update();
|
||
startWork();
|
||
stopWork();
|
||
break;
|
||
}
|
||
|
||
case wopQuerySubstitutablePathInfo: {
|
||
Path path = absPath(readString(from));
|
||
startWork();
|
||
SubstitutablePathInfos infos;
|
||
store->querySubstitutablePathInfos(singleton<PathSet>(path), infos);
|
||
stopWork();
|
||
SubstitutablePathInfos::iterator i = infos.find(path);
|
||
if (i == infos.end())
|
||
to << 0;
|
||
else {
|
||
to << 1 << i->second.deriver << i->second.references << i->second.downloadSize;
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 7)
|
||
to << i->second.narSize;
|
||
}
|
||
break;
|
||
}
|
||
|
||
case wopQuerySubstitutablePathInfos: {
|
||
PathSet paths = readStorePaths<PathSet>(from);
|
||
startWork();
|
||
SubstitutablePathInfos infos;
|
||
store->querySubstitutablePathInfos(paths, infos);
|
||
stopWork();
|
||
to << infos.size();
|
||
for (auto & i : infos) {
|
||
to << i.first << i.second.deriver << i.second.references
|
||
<< i.second.downloadSize << i.second.narSize;
|
||
}
|
||
break;
|
||
}
|
||
|
||
case wopQueryAllValidPaths: {
|
||
startWork();
|
||
PathSet paths = store->queryAllValidPaths();
|
||
stopWork();
|
||
to << paths;
|
||
break;
|
||
}
|
||
|
||
case wopQueryFailedPaths: {
|
||
startWork();
|
||
PathSet paths = store->queryFailedPaths();
|
||
stopWork();
|
||
to << paths;
|
||
break;
|
||
}
|
||
|
||
case wopClearFailedPaths: {
|
||
PathSet paths = readStrings<PathSet>(from);
|
||
startWork();
|
||
store->clearFailedPaths(paths);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopQueryPathInfo: {
|
||
Path path = readStorePath(from);
|
||
startWork();
|
||
ValidPathInfo info = store->queryPathInfo(path);
|
||
stopWork();
|
||
to << info.deriver << printHash(info.hash) << info.references
|
||
<< info.registrationTime << info.narSize;
|
||
break;
|
||
}
|
||
|
||
case wopOptimiseStore:
|
||
startWork();
|
||
store->optimiseStore();
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
|
||
case wopVerifyStore: {
|
||
bool checkContents = readInt(from) != 0;
|
||
bool repair = readInt(from) != 0;
|
||
startWork();
|
||
if (repair && !trusted)
|
||
throw Error("you are not privileged to repair paths");
|
||
bool errors = store->verifyStore(checkContents, repair);
|
||
stopWork();
|
||
to << errors;
|
||
break;
|
||
}
|
||
|
||
default:
|
||
throw Error(format("invalid operation %1%") % op);
|
||
}
|
||
}
|
||
|
||
|
||
static void processConnection(bool trusted)
|
||
{
|
||
MonitorFdHup monitor(from.fd);
|
||
|
||
canSendStderr = false;
|
||
_writeToStderr = tunnelStderr;
|
||
|
||
/* Exchange the greeting. */
|
||
unsigned int magic = readInt(from);
|
||
if (magic != WORKER_MAGIC_1) throw Error("protocol mismatch");
|
||
to << WORKER_MAGIC_2 << PROTOCOL_VERSION;
|
||
to.flush();
|
||
unsigned int clientVersion = readInt(from);
|
||
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 14 && readInt(from))
|
||
setAffinityTo(readInt(from));
|
||
|
||
bool reserveSpace = true;
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 11)
|
||
reserveSpace = readInt(from) != 0;
|
||
|
||
/* Send startup error messages to the client. */
|
||
startWork();
|
||
|
||
try {
|
||
|
||
/* If we can't accept clientVersion, then throw an error
|
||
*here* (not above). */
|
||
|
||
#if 0
|
||
/* Prevent users from doing something very dangerous. */
|
||
if (geteuid() == 0 &&
|
||
querySetting("build-users-group", "") == "")
|
||
throw Error("if you run ‘nix-daemon’ as root, then you MUST set ‘build-users-group’!");
|
||
#endif
|
||
|
||
/* Open the store. */
|
||
store = std::shared_ptr<StoreAPI>(new LocalStore(reserveSpace));
|
||
|
||
stopWork();
|
||
to.flush();
|
||
|
||
} catch (Error & e) {
|
||
stopWork(false, e.msg(), GET_PROTOCOL_MINOR(clientVersion) >= 8 ? 1 : 0);
|
||
to.flush();
|
||
return;
|
||
}
|
||
|
||
/* Process client requests. */
|
||
unsigned int opCount = 0;
|
||
|
||
while (true) {
|
||
WorkerOp op;
|
||
try {
|
||
op = (WorkerOp) readInt(from);
|
||
} catch (Interrupted & e) {
|
||
break;
|
||
} catch (EndOfFile & e) {
|
||
break;
|
||
}
|
||
|
||
opCount++;
|
||
|
||
try {
|
||
performOp(trusted, clientVersion, from, to, op);
|
||
} catch (Error & e) {
|
||
/* If we're not in a state where we can send replies, then
|
||
something went wrong processing the input of the
|
||
client. This can happen especially if I/O errors occur
|
||
during addTextToStore() / importPath(). If that
|
||
happens, just send the error message and exit. */
|
||
bool errorAllowed = canSendStderr;
|
||
stopWork(false, e.msg(), GET_PROTOCOL_MINOR(clientVersion) >= 8 ? e.status : 0);
|
||
if (!errorAllowed) throw;
|
||
} catch (std::bad_alloc & e) {
|
||
stopWork(false, "Nix daemon out of memory", GET_PROTOCOL_MINOR(clientVersion) >= 8 ? 1 : 0);
|
||
throw;
|
||
}
|
||
|
||
to.flush();
|
||
|
||
assert(!canSendStderr);
|
||
};
|
||
|
||
canSendStderr = false;
|
||
_isInterrupted = false;
|
||
printMsg(lvlDebug, format("%1% operations") % opCount);
|
||
}
|
||
|
||
|
||
static void sigChldHandler(int sigNo)
|
||
{
|
||
/* Reap all dead children. */
|
||
while (waitpid(-1, 0, WNOHANG) > 0) ;
|
||
}
|
||
|
||
|
||
static void setSigChldAction(bool autoReap)
|
||
{
|
||
struct sigaction act, oact;
|
||
act.sa_handler = autoReap ? sigChldHandler : SIG_DFL;
|
||
sigfillset(&act.sa_mask);
|
||
act.sa_flags = 0;
|
||
if (sigaction(SIGCHLD, &act, &oact))
|
||
throw SysError("setting SIGCHLD handler");
|
||
}
|
||
|
||
|
||
bool matchUser(const string & user, const string & group, const Strings & users)
|
||
{
|
||
if (find(users.begin(), users.end(), "*") != users.end())
|
||
return true;
|
||
|
||
if (find(users.begin(), users.end(), user) != users.end())
|
||
return true;
|
||
|
||
for (auto & i : users)
|
||
if (string(i, 0, 1) == "@") {
|
||
if (group == string(i, 1)) return true;
|
||
struct group * gr = getgrnam(i.c_str() + 1);
|
||
if (!gr) continue;
|
||
for (char * * mem = gr->gr_mem; *mem; mem++)
|
||
if (user == string(*mem)) return true;
|
||
}
|
||
|
||
return false;
|
||
}
|
||
|
||
|
||
struct PeerInfo
|
||
{
|
||
bool pidKnown;
|
||
pid_t pid;
|
||
bool uidKnown;
|
||
uid_t uid;
|
||
bool gidKnown;
|
||
gid_t gid;
|
||
};
|
||
|
||
|
||
/* Get the identity of the caller, if possible. */
|
||
static PeerInfo getPeerInfo(int remote)
|
||
{
|
||
PeerInfo peer = { false, 0, false, 0, false, 0 };
|
||
|
||
#if defined(SO_PEERCRED)
|
||
|
||
ucred cred;
|
||
socklen_t credLen = sizeof(cred);
|
||
if (getsockopt(remote, SOL_SOCKET, SO_PEERCRED, &cred, &credLen) == -1)
|
||
throw SysError("getting peer credentials");
|
||
peer = { true, cred.pid, true, cred.uid, true, cred.gid };
|
||
|
||
#elif defined(LOCAL_PEERCRED)
|
||
|
||
xucred cred;
|
||
socklen_t credLen = sizeof(cred);
|
||
if (getsockopt(remote, SOL_LOCAL, LOCAL_PEERCRED, &cred, &credLen) == -1)
|
||
throw SysError("getting peer credentials");
|
||
peer = { false, 0, true, cred.cr_uid, false, 0 };
|
||
|
||
#endif
|
||
|
||
return peer;
|
||
}
|
||
|
||
|
||
#define SD_LISTEN_FDS_START 3
|
||
|
||
|
||
static void daemonLoop(char * * argv)
|
||
{
|
||
if (chdir("/") == -1)
|
||
throw SysError("cannot change current directory");
|
||
|
||
/* Get rid of children automatically; don't let them become
|
||
zombies. */
|
||
setSigChldAction(true);
|
||
|
||
AutoCloseFD fdSocket;
|
||
|
||
/* Handle socket-based activation by systemd. */
|
||
if (getEnv("LISTEN_FDS") != "") {
|
||
if (getEnv("LISTEN_PID") != int2String(getpid()) || getEnv("LISTEN_FDS") != "1")
|
||
throw Error("unexpected systemd environment variables");
|
||
fdSocket = SD_LISTEN_FDS_START;
|
||
}
|
||
|
||
/* Otherwise, create and bind to a Unix domain socket. */
|
||
else {
|
||
|
||
/* Create and bind to a Unix domain socket. */
|
||
fdSocket = socket(PF_UNIX, SOCK_STREAM, 0);
|
||
if (fdSocket == -1)
|
||
throw SysError("cannot create Unix domain socket");
|
||
|
||
string socketPath = settings.nixDaemonSocketFile;
|
||
|
||
createDirs(dirOf(socketPath));
|
||
|
||
/* Urgh, sockaddr_un allows path names of only 108 characters.
|
||
So chdir to the socket directory so that we can pass a
|
||
relative path name. */
|
||
if (chdir(dirOf(socketPath).c_str()) == -1)
|
||
throw SysError("cannot change current directory");
|
||
Path socketPathRel = "./" + baseNameOf(socketPath);
|
||
|
||
struct sockaddr_un addr;
|
||
addr.sun_family = AF_UNIX;
|
||
if (socketPathRel.size() >= sizeof(addr.sun_path))
|
||
throw Error(format("socket path ‘%1%’ is too long") % socketPathRel);
|
||
strcpy(addr.sun_path, socketPathRel.c_str());
|
||
|
||
unlink(socketPath.c_str());
|
||
|
||
/* Make sure that the socket is created with 0666 permission
|
||
(everybody can connect --- provided they have access to the
|
||
directory containing the socket). */
|
||
mode_t oldMode = umask(0111);
|
||
int res = bind(fdSocket, (struct sockaddr *) &addr, sizeof(addr));
|
||
umask(oldMode);
|
||
if (res == -1)
|
||
throw SysError(format("cannot bind to socket ‘%1%’") % socketPath);
|
||
|
||
if (chdir("/") == -1) /* back to the root */
|
||
throw SysError("cannot change current directory");
|
||
|
||
if (listen(fdSocket, 5) == -1)
|
||
throw SysError(format("cannot listen on socket ‘%1%’") % socketPath);
|
||
}
|
||
|
||
closeOnExec(fdSocket);
|
||
|
||
/* Loop accepting connections. */
|
||
while (1) {
|
||
|
||
try {
|
||
/* Important: the server process *cannot* open the SQLite
|
||
database, because it doesn't like forks very much. */
|
||
assert(!store);
|
||
|
||
/* Accept a connection. */
|
||
struct sockaddr_un remoteAddr;
|
||
socklen_t remoteAddrLen = sizeof(remoteAddr);
|
||
|
||
AutoCloseFD remote = accept(fdSocket,
|
||
(struct sockaddr *) &remoteAddr, &remoteAddrLen);
|
||
checkInterrupt();
|
||
if (remote == -1) {
|
||
if (errno == EINTR) continue;
|
||
throw SysError("accepting connection");
|
||
}
|
||
|
||
closeOnExec(remote);
|
||
|
||
bool trusted = false;
|
||
PeerInfo peer = getPeerInfo(remote);
|
||
|
||
struct passwd * pw = peer.uidKnown ? getpwuid(peer.uid) : 0;
|
||
string user = pw ? pw->pw_name : int2String(peer.uid);
|
||
|
||
struct group * gr = peer.gidKnown ? getgrgid(peer.gid) : 0;
|
||
string group = gr ? gr->gr_name : int2String(peer.gid);
|
||
|
||
Strings trustedUsers = settings.get("trusted-users", Strings({"root"}));
|
||
Strings allowedUsers = settings.get("allowed-users", Strings({"*"}));
|
||
|
||
if (matchUser(user, group, trustedUsers))
|
||
trusted = true;
|
||
|
||
if (!trusted && !matchUser(user, group, allowedUsers))
|
||
throw Error(format("user ‘%1%’ is not allowed to connect to the Nix daemon") % user);
|
||
|
||
printMsg(lvlInfo, format((string) "accepted connection from pid %1%, user %2%" + (trusted ? " (trusted)" : ""))
|
||
% (peer.pidKnown ? int2String(peer.pid) : "<unknown>")
|
||
% (peer.uidKnown ? user : "<unknown>"));
|
||
|
||
/* Fork a child to handle the connection. */
|
||
ProcessOptions options;
|
||
options.errorPrefix = "unexpected Nix daemon error: ";
|
||
options.dieWithParent = false;
|
||
options.runExitHandlers = true;
|
||
options.allowVfork = false;
|
||
startProcess([&]() {
|
||
fdSocket.close();
|
||
|
||
/* Background the daemon. */
|
||
if (setsid() == -1)
|
||
throw SysError(format("creating a new session"));
|
||
|
||
/* Restore normal handling of SIGCHLD. */
|
||
setSigChldAction(false);
|
||
|
||
/* For debugging, stuff the pid into argv[1]. */
|
||
if (peer.pidKnown && argv[1]) {
|
||
string processName = int2String(peer.pid);
|
||
strncpy(argv[1], processName.c_str(), strlen(argv[1]));
|
||
}
|
||
|
||
/* Handle the connection. */
|
||
from.fd = remote;
|
||
to.fd = remote;
|
||
processConnection(trusted);
|
||
|
||
exit(0);
|
||
}, options);
|
||
|
||
} catch (Interrupted & e) {
|
||
throw;
|
||
} catch (Error & e) {
|
||
printMsg(lvlError, format("error processing connection: %1%") % e.msg());
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
int main(int argc, char * * argv)
|
||
{
|
||
return handleExceptions(argv[0], [&]() {
|
||
initNix();
|
||
|
||
parseCmdLine(argc, argv, [&](Strings::iterator & arg, const Strings::iterator & end) {
|
||
if (*arg == "--daemon")
|
||
; /* ignored for backwards compatibility */
|
||
else if (*arg == "--help")
|
||
showManPage("nix-daemon");
|
||
else if (*arg == "--version")
|
||
printVersion("nix-daemon");
|
||
else return false;
|
||
return true;
|
||
});
|
||
|
||
daemonLoop(argv);
|
||
});
|
||
}
|