forked from lix-project/lix
1041 lines
30 KiB
C++
1041 lines
30 KiB
C++
#include "shared.hh"
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#include "local-store.hh"
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#include "util.hh"
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#include "serialise.hh"
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#include "worker-protocol.hh"
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#include "archive.hh"
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#include "affinity.hh"
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#include "globals.hh"
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#include "monitor-fd.hh"
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#include "derivations.hh"
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#include <algorithm>
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#include <cstring>
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#include <unistd.h>
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#include <signal.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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#include <sys/stat.h>
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#include <sys/socket.h>
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#include <sys/un.h>
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#include <errno.h>
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#include <pwd.h>
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#include <grp.h>
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#include <fcntl.h>
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#include <limits.h>
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#if __APPLE__ || __FreeBSD__
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#include <sys/ucred.h>
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#endif
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using namespace nix;
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#ifndef __linux__
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#define SPLICE_F_MOVE 0
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static ssize_t splice(int fd_in, void *off_in, int fd_out, void *off_out, size_t len, unsigned int flags)
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{
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/* We ignore most parameters, we just have them for conformance with the linux syscall */
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char buf[8192];
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auto read_count = read(fd_in, buf, sizeof(buf));
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if (read_count == -1)
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return read_count;
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auto write_count = decltype(read_count)(0);
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while (write_count < read_count) {
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auto res = write(fd_out, buf + write_count, read_count - write_count);
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if (res == -1)
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return res;
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write_count += res;
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}
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return read_count;
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}
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#endif
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static FdSource from(STDIN_FILENO);
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static FdSink to(STDOUT_FILENO);
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static bool canSendStderr;
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static Logger * defaultLogger;
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/* Logger that forwards log messages to the client, *if* we're in a
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state where the protocol allows it (i.e., when canSendStderr is
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true). */
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class TunnelLogger : public Logger
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{
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void log(Verbosity lvl, const FormatOrString & fs) override
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{
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if (lvl > verbosity) return;
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if (canSendStderr) {
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try {
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to << STDERR_NEXT << (fs.s + "\n");
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to.flush();
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} catch (...) {
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/* Write failed; that means that the other side is
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gone. */
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canSendStderr = false;
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throw;
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}
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} else
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defaultLogger->log(lvl, fs);
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}
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void event(const Event & ev) override
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{
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}
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};
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/* startWork() means that we're starting an operation for which we
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want to send out stderr to the client. */
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static void startWork()
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{
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canSendStderr = true;
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}
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/* stopWork() means that we're done; stop sending stderr to the
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client. */
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static void stopWork(bool success = true, const string & msg = "", unsigned int status = 0)
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{
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canSendStderr = false;
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if (success)
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to << STDERR_LAST;
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else {
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to << STDERR_ERROR << msg;
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if (status != 0) to << status;
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}
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}
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struct TunnelSink : Sink
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{
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Sink & to;
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TunnelSink(Sink & to) : to(to) { }
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virtual void operator () (const unsigned char * data, size_t len)
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{
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to << STDERR_WRITE;
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writeString(data, len, to);
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}
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};
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struct TunnelSource : BufferedSource
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{
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Source & from;
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TunnelSource(Source & from) : from(from) { }
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size_t readUnbuffered(unsigned char * data, size_t len)
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{
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to << STDERR_READ << len;
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to.flush();
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size_t n = readString(data, len, from);
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if (n == 0) throw EndOfFile("unexpected end-of-file");
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return n;
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}
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};
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/* If the NAR archive contains a single file at top-level, then save
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the contents of the file to `s'. Otherwise barf. */
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struct RetrieveRegularNARSink : ParseSink
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{
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bool regular;
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string s;
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RetrieveRegularNARSink() : regular(true) { }
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void createDirectory(const Path & path)
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{
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regular = false;
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}
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void receiveContents(unsigned char * data, unsigned int len)
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{
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s.append((const char *) data, len);
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}
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void createSymlink(const Path & path, const string & target)
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{
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regular = false;
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}
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};
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static void performOp(ref<LocalStore> store, bool trusted, unsigned int clientVersion,
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Source & from, Sink & to, unsigned int op)
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{
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switch (op) {
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case wopIsValidPath: {
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/* 'readStorePath' could raise an error leading to the connection
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being closed. To be able to recover from an invalid path error,
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call 'startWork' early, and do 'assertStorePath' afterwards so
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that the 'Error' exception handler doesn't close the
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connection. */
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Path path = readString(from);
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startWork();
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store->assertStorePath(path);
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bool result = store->isValidPath(path);
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stopWork();
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to << result;
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break;
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}
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case wopQueryValidPaths: {
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PathSet paths = readStorePaths<PathSet>(*store, from);
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startWork();
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PathSet res = store->queryValidPaths(paths);
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stopWork();
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to << res;
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break;
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}
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case wopHasSubstitutes: {
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Path path = readStorePath(*store, from);
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startWork();
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PathSet res = store->querySubstitutablePaths({path});
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stopWork();
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to << (res.find(path) != res.end());
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break;
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}
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case wopQuerySubstitutablePaths: {
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PathSet paths = readStorePaths<PathSet>(*store, from);
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startWork();
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PathSet res = store->querySubstitutablePaths(paths);
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stopWork();
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to << res;
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break;
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}
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case wopQueryPathHash: {
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Path path = readStorePath(*store, from);
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startWork();
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auto hash = store->queryPathInfo(path)->narHash;
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stopWork();
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to << printHash(hash);
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break;
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}
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case wopQueryReferences:
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case wopQueryReferrers:
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case wopQueryValidDerivers:
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case wopQueryDerivationOutputs: {
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Path path = readStorePath(*store, from);
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startWork();
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PathSet paths;
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if (op == wopQueryReferences)
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paths = store->queryPathInfo(path)->references;
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else if (op == wopQueryReferrers)
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store->queryReferrers(path, paths);
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else if (op == wopQueryValidDerivers)
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paths = store->queryValidDerivers(path);
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else paths = store->queryDerivationOutputs(path);
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stopWork();
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to << paths;
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break;
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}
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case wopQueryDerivationOutputNames: {
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Path path = readStorePath(*store, from);
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startWork();
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StringSet names;
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names = store->queryDerivationOutputNames(path);
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stopWork();
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to << names;
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break;
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}
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case wopQueryDeriver: {
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Path path = readStorePath(*store, from);
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startWork();
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auto deriver = store->queryPathInfo(path)->deriver;
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stopWork();
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to << deriver;
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break;
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}
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case wopQueryPathFromHashPart: {
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string hashPart = readString(from);
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startWork();
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Path path = store->queryPathFromHashPart(hashPart);
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stopWork();
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to << path;
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break;
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}
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case wopAddToStore: {
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bool fixed, recursive;
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std::string s, baseName;
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from >> baseName >> fixed /* obsolete */ >> recursive >> s;
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/* Compatibility hack. */
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if (!fixed) {
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s = "sha256";
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recursive = true;
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}
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HashType hashAlgo = parseHashType(s);
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TeeSource savedNAR(from);
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RetrieveRegularNARSink savedRegular;
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if (recursive) {
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/* Get the entire NAR dump from the client and save it to
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a string so that we can pass it to
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addToStoreFromDump(). */
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ParseSink sink; /* null sink; just parse the NAR */
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parseDump(sink, savedNAR);
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} else
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parseDump(savedRegular, from);
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startWork();
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if (!savedRegular.regular) throw Error("regular file expected");
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Path path = store->addToStoreFromDump(recursive ? *savedNAR.data : savedRegular.s, baseName, recursive, hashAlgo);
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stopWork();
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to << path;
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break;
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}
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case wopAddTextToStore: {
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string suffix = readString(from);
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string s = readString(from);
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PathSet refs = readStorePaths<PathSet>(*store, from);
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startWork();
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Path path = store->addTextToStore(suffix, s, refs, false);
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stopWork();
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to << path;
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break;
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}
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case wopExportPath: {
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Path path = readStorePath(*store, from);
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readInt(from); // obsolete
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startWork();
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TunnelSink sink(to);
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store->exportPath(path, sink);
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stopWork();
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to << 1;
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break;
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}
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case wopImportPaths: {
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startWork();
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TunnelSource source(from);
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Paths paths = store->importPaths(source, 0, trusted);
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stopWork();
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to << paths;
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break;
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}
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case wopBuildPaths: {
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PathSet drvs = readStorePaths<PathSet>(*store, from);
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BuildMode mode = bmNormal;
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if (GET_PROTOCOL_MINOR(clientVersion) >= 15) {
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mode = (BuildMode) readInt(from);
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/* Repairing is not atomic, so disallowed for "untrusted"
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clients. */
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if (mode == bmRepair && !trusted)
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throw Error("repairing is not supported when building through the Nix daemon");
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}
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startWork();
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store->buildPaths(drvs, mode);
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stopWork();
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to << 1;
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break;
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}
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case wopBuildDerivation: {
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Path drvPath = readStorePath(*store, from);
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BasicDerivation drv;
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readDerivation(from, *store, drv);
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BuildMode buildMode = (BuildMode) readInt(from);
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startWork();
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if (!trusted)
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throw Error("you are not privileged to build derivations");
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auto res = store->buildDerivation(drvPath, drv, buildMode);
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stopWork();
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to << res.status << res.errorMsg;
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break;
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}
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case wopEnsurePath: {
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Path path = readStorePath(*store, from);
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startWork();
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store->ensurePath(path);
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stopWork();
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to << 1;
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break;
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}
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case wopAddTempRoot: {
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Path path = readStorePath(*store, from);
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startWork();
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store->addTempRoot(path);
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stopWork();
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to << 1;
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break;
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}
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case wopAddIndirectRoot: {
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Path path = absPath(readString(from));
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startWork();
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store->addIndirectRoot(path);
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stopWork();
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to << 1;
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break;
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}
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case wopSyncWithGC: {
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startWork();
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store->syncWithGC();
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stopWork();
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to << 1;
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break;
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}
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case wopFindRoots: {
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startWork();
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Roots roots = store->findRoots();
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stopWork();
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to << roots.size();
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for (auto & i : roots)
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to << i.first << i.second;
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break;
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}
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case wopCollectGarbage: {
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GCOptions options;
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options.action = (GCOptions::GCAction) readInt(from);
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options.pathsToDelete = readStorePaths<PathSet>(*store, from);
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from >> options.ignoreLiveness >> options.maxFreed;
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// obsolete fields
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readInt(from);
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readInt(from);
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readInt(from);
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GCResults results;
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startWork();
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if (options.ignoreLiveness)
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throw Error("you are not allowed to ignore liveness");
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store->collectGarbage(options, results);
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stopWork();
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to << results.paths << results.bytesFreed << 0 /* obsolete */;
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break;
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}
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case wopSetOptions: {
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settings.keepFailed = readInt(from);
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settings.keepGoing = readInt(from);
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settings.tryFallback = readInt(from);
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verbosity = (Verbosity) readInt(from);
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settings.maxBuildJobs.assign(readInt(from));
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settings.maxSilentTime = readInt(from);
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settings.useBuildHook = readInt(from) != 0;
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settings.verboseBuild = lvlError == (Verbosity) readInt(from);
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readInt(from); // obsolete logType
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readInt(from); // obsolete printBuildTrace
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settings.buildCores = readInt(from);
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settings.useSubstitutes = readInt(from);
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StringMap overrides;
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if (GET_PROTOCOL_MINOR(clientVersion) >= 12) {
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unsigned int n = readInt(from);
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for (unsigned int i = 0; i < n; i++) {
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string name = readString(from);
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string value = readString(from);
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overrides.emplace(name, value);
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}
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}
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startWork();
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for (auto & i : overrides) {
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auto & name(i.first);
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auto & value(i.second);
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auto setSubstituters = [&](Setting<Strings> & res) {
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if (name != res.name && res.aliases.count(name) == 0)
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return false;
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StringSet trusted = settings.trustedSubstituters;
|
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for (auto & s : settings.substituters.get())
|
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trusted.insert(s);
|
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Strings subs;
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auto ss = tokenizeString<Strings>(value);
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for (auto & s : ss)
|
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if (trusted.count(s))
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subs.push_back(s);
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else
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warn("ignoring untrusted substituter '%s'", s);
|
||
res = subs;
|
||
return true;
|
||
};
|
||
|
||
try {
|
||
if (name == "ssh-auth-sock") // obsolete
|
||
;
|
||
else if (trusted
|
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|| name == settings.buildTimeout.name
|
||
|| name == settings.connectTimeout.name)
|
||
settings.set(name, value);
|
||
else if (setSubstituters(settings.substituters))
|
||
;
|
||
else if (setSubstituters(settings.extraSubstituters))
|
||
;
|
||
else
|
||
debug("ignoring untrusted setting '%s'", name);
|
||
} catch (UsageError & e) {
|
||
warn(e.what());
|
||
}
|
||
}
|
||
|
||
stopWork();
|
||
break;
|
||
}
|
||
|
||
case wopQuerySubstitutablePathInfo: {
|
||
Path path = absPath(readString(from));
|
||
startWork();
|
||
SubstitutablePathInfos infos;
|
||
store->querySubstitutablePathInfos({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 << i->second.narSize;
|
||
}
|
||
break;
|
||
}
|
||
|
||
case wopQuerySubstitutablePathInfos: {
|
||
PathSet paths = readStorePaths<PathSet>(*store, 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 wopQueryPathInfo: {
|
||
Path path = readStorePath(*store, from);
|
||
std::shared_ptr<const ValidPathInfo> info;
|
||
startWork();
|
||
try {
|
||
info = store->queryPathInfo(path);
|
||
} catch (InvalidPath &) {
|
||
if (GET_PROTOCOL_MINOR(clientVersion) < 17) throw;
|
||
}
|
||
stopWork();
|
||
if (info) {
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 17)
|
||
to << 1;
|
||
to << info->deriver << printHash(info->narHash) << info->references
|
||
<< info->registrationTime << info->narSize;
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 16) {
|
||
to << info->ultimate
|
||
<< info->sigs
|
||
<< info->ca;
|
||
}
|
||
} else {
|
||
assert(GET_PROTOCOL_MINOR(clientVersion) >= 17);
|
||
to << 0;
|
||
}
|
||
break;
|
||
}
|
||
|
||
case wopOptimiseStore:
|
||
startWork();
|
||
store->optimiseStore();
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
|
||
case wopVerifyStore: {
|
||
bool checkContents, repair;
|
||
from >> checkContents >> repair;
|
||
startWork();
|
||
if (repair && !trusted)
|
||
throw Error("you are not privileged to repair paths");
|
||
bool errors = store->verifyStore(checkContents, repair);
|
||
stopWork();
|
||
to << errors;
|
||
break;
|
||
}
|
||
|
||
case wopAddSignatures: {
|
||
Path path = readStorePath(*store, from);
|
||
StringSet sigs = readStrings<StringSet>(from);
|
||
startWork();
|
||
if (!trusted)
|
||
throw Error("you are not privileged to add signatures");
|
||
store->addSignatures(path, sigs);
|
||
stopWork();
|
||
to << 1;
|
||
break;
|
||
}
|
||
|
||
case wopNarFromPath: {
|
||
auto path = readStorePath(*store, from);
|
||
startWork();
|
||
stopWork();
|
||
dumpPath(path, to);
|
||
break;
|
||
}
|
||
|
||
case wopAddToStoreNar: {
|
||
bool repair, dontCheckSigs;
|
||
ValidPathInfo info;
|
||
info.path = readStorePath(*store, from);
|
||
from >> info.deriver;
|
||
if (!info.deriver.empty())
|
||
store->assertStorePath(info.deriver);
|
||
info.narHash = parseHash(htSHA256, readString(from));
|
||
info.references = readStorePaths<PathSet>(*store, from);
|
||
from >> info.registrationTime >> info.narSize >> info.ultimate;
|
||
info.sigs = readStrings<StringSet>(from);
|
||
from >> info.ca >> repair >> dontCheckSigs;
|
||
if (!trusted && dontCheckSigs)
|
||
dontCheckSigs = false;
|
||
if (!trusted)
|
||
info.ultimate = false;
|
||
|
||
TeeSink tee(from);
|
||
parseDump(tee, tee.source);
|
||
|
||
startWork();
|
||
store->addToStore(info, tee.source.data, repair, dontCheckSigs, nullptr);
|
||
stopWork();
|
||
break;
|
||
}
|
||
|
||
case wopQueryMissing: {
|
||
PathSet targets = readStorePaths<PathSet>(*store, from);
|
||
startWork();
|
||
PathSet willBuild, willSubstitute, unknown;
|
||
unsigned long long downloadSize, narSize;
|
||
store->queryMissing(targets, willBuild, willSubstitute, unknown, downloadSize, narSize);
|
||
stopWork();
|
||
to << willBuild << willSubstitute << unknown << downloadSize << narSize;
|
||
break;
|
||
}
|
||
|
||
default:
|
||
throw Error(format("invalid operation %1%") % op);
|
||
}
|
||
}
|
||
|
||
|
||
static void processConnection(bool trusted)
|
||
{
|
||
MonitorFdHup monitor(from.fd);
|
||
|
||
canSendStderr = false;
|
||
defaultLogger = logger;
|
||
logger = new TunnelLogger();
|
||
|
||
/* 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 (clientVersion < 0x10a)
|
||
throw Error("the Nix client version is too old");
|
||
|
||
if (GET_PROTOCOL_MINOR(clientVersion) >= 14 && readInt(from))
|
||
setAffinityTo(readInt(from));
|
||
|
||
readInt(from); // obsolete reserveSpace
|
||
|
||
/* 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::Params params; // FIXME: get params from somewhere
|
||
// Disable caching since the client already does that.
|
||
params["path-info-cache-size"] = "0";
|
||
auto store = make_ref<LocalStore>(params);
|
||
|
||
stopWork();
|
||
to.flush();
|
||
|
||
/* 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(store, 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(), e.status);
|
||
if (!errorAllowed) throw;
|
||
} catch (std::bad_alloc & e) {
|
||
stopWork(false, "Nix daemon out of memory", 1);
|
||
throw;
|
||
}
|
||
|
||
to.flush();
|
||
|
||
assert(!canSendStderr);
|
||
};
|
||
|
||
canSendStderr = false;
|
||
_isInterrupted = false;
|
||
debug(format("%1% operations") % opCount);
|
||
|
||
} catch (Error & e) {
|
||
stopWork(false, e.msg(), 1);
|
||
to.flush();
|
||
return;
|
||
}
|
||
}
|
||
|
||
|
||
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)
|
||
|
||
#if !defined(SOL_LOCAL)
|
||
#define SOL_LOCAL 0
|
||
#endif
|
||
|
||
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") != std::to_string(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)
|
||
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.get(), (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.get(), 5) == -1)
|
||
throw SysError(format("cannot listen on socket ‘%1%’") % socketPath);
|
||
}
|
||
|
||
closeOnExec(fdSocket.get());
|
||
|
||
/* Loop accepting connections. */
|
||
while (1) {
|
||
|
||
try {
|
||
/* Accept a connection. */
|
||
struct sockaddr_un remoteAddr;
|
||
socklen_t remoteAddrLen = sizeof(remoteAddr);
|
||
|
||
AutoCloseFD remote = accept(fdSocket.get(),
|
||
(struct sockaddr *) &remoteAddr, &remoteAddrLen);
|
||
checkInterrupt();
|
||
if (!remote) {
|
||
if (errno == EINTR) continue;
|
||
throw SysError("accepting connection");
|
||
}
|
||
|
||
closeOnExec(remote.get());
|
||
|
||
bool trusted = false;
|
||
PeerInfo peer = getPeerInfo(remote.get());
|
||
|
||
struct passwd * pw = peer.uidKnown ? getpwuid(peer.uid) : 0;
|
||
string user = pw ? pw->pw_name : std::to_string(peer.uid);
|
||
|
||
struct group * gr = peer.gidKnown ? getgrgid(peer.gid) : 0;
|
||
string group = gr ? gr->gr_name : std::to_string(peer.gid);
|
||
|
||
Strings trustedUsers = settings.trustedUsers;
|
||
Strings allowedUsers = settings.allowedUsers;
|
||
|
||
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);
|
||
|
||
printInfo(format((string) "accepted connection from pid %1%, user %2%" + (trusted ? " (trusted)" : ""))
|
||
% (peer.pidKnown ? std::to_string(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 = -1;
|
||
|
||
/* 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 = std::to_string(peer.pid);
|
||
strncpy(argv[1], processName.c_str(), strlen(argv[1]));
|
||
}
|
||
|
||
/* Handle the connection. */
|
||
from.fd = remote.get();
|
||
to.fd = remote.get();
|
||
processConnection(trusted);
|
||
|
||
exit(0);
|
||
}, options);
|
||
|
||
} catch (Interrupted & e) {
|
||
throw;
|
||
} catch (Error & e) {
|
||
printError(format("error processing connection: %1%") % e.msg());
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
int main(int argc, char * * argv)
|
||
{
|
||
return handleExceptions(argv[0], [&]() {
|
||
initNix();
|
||
|
||
auto stdio = false;
|
||
|
||
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 if (*arg == "--stdio")
|
||
stdio = true;
|
||
else return false;
|
||
return true;
|
||
});
|
||
|
||
if (stdio) {
|
||
if (getStoreType() == tDaemon) {
|
||
/* Forward on this connection to the real daemon */
|
||
auto socketPath = settings.nixDaemonSocketFile;
|
||
auto s = socket(PF_UNIX, SOCK_STREAM, 0);
|
||
if (s == -1)
|
||
throw SysError("creating Unix domain socket");
|
||
|
||
auto socketDir = dirOf(socketPath);
|
||
if (chdir(socketDir.c_str()) == -1)
|
||
throw SysError(format("changing to socket directory ‘%1%’") % socketDir);
|
||
|
||
auto socketName = baseNameOf(socketPath);
|
||
auto addr = sockaddr_un{};
|
||
addr.sun_family = AF_UNIX;
|
||
if (socketName.size() + 1 >= sizeof(addr.sun_path))
|
||
throw Error(format("socket name %1% is too long") % socketName);
|
||
strcpy(addr.sun_path, socketName.c_str());
|
||
|
||
if (connect(s, (struct sockaddr *) &addr, sizeof(addr)) == -1)
|
||
throw SysError(format("cannot connect to daemon at %1%") % socketPath);
|
||
|
||
auto nfds = (s > STDIN_FILENO ? s : STDIN_FILENO) + 1;
|
||
while (true) {
|
||
fd_set fds;
|
||
FD_ZERO(&fds);
|
||
FD_SET(s, &fds);
|
||
FD_SET(STDIN_FILENO, &fds);
|
||
if (select(nfds, &fds, nullptr, nullptr, nullptr) == -1)
|
||
throw SysError("waiting for data from client or server");
|
||
if (FD_ISSET(s, &fds)) {
|
||
auto res = splice(s, nullptr, STDOUT_FILENO, nullptr, SSIZE_MAX, SPLICE_F_MOVE);
|
||
if (res == -1)
|
||
throw SysError("splicing data from daemon socket to stdout");
|
||
else if (res == 0)
|
||
throw EndOfFile("unexpected EOF from daemon socket");
|
||
}
|
||
if (FD_ISSET(STDIN_FILENO, &fds)) {
|
||
auto res = splice(STDIN_FILENO, nullptr, s, nullptr, SSIZE_MAX, SPLICE_F_MOVE);
|
||
if (res == -1)
|
||
throw SysError("splicing data from stdin to daemon socket");
|
||
else if (res == 0)
|
||
return;
|
||
}
|
||
}
|
||
} else {
|
||
processConnection(true);
|
||
}
|
||
} else {
|
||
daemonLoop(argv);
|
||
}
|
||
});
|
||
}
|