mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-11 00:36:20 +02:00
887 lines
25 KiB
C++
887 lines
25 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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#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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static FdSource from(STDIN_FILENO);
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static FdSink to(STDOUT_FILENO);
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bool canSendStderr;
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/* This function is called anytime we want to write something to
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stderr. If we're in a state where the protocol allows it (i.e.,
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when canSendStderr), send the message to the client over the
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socket. */
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static void tunnelStderr(const unsigned char * buf, size_t count)
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{
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if (canSendStderr) {
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try {
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to << STDERR_NEXT;
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writeString(buf, count, to);
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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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writeFull(STDERR_FILENO, buf, count);
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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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/* Adapter class of a Source that saves all data read to `s'. */
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struct SavingSourceAdapter : Source
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{
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Source & orig;
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string s;
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SavingSourceAdapter(Source & orig) : orig(orig) { }
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size_t read(unsigned char * data, size_t len)
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{
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size_t n = orig.read(data, len);
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s.append((const char *) data, n);
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return n;
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}
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};
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static void performOp(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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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>(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(from);
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startWork();
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PathSet res = store->querySubstitutablePaths(singleton<PathSet>(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>(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(from);
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startWork();
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Hash hash = store->queryPathHash(path);
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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(from);
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startWork();
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PathSet paths;
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if (op == wopQueryReferences)
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store->queryReferences(path, paths);
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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(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(from);
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startWork();
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Path deriver = store->queryDeriver(path);
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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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string baseName = readString(from);
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bool fixed = readInt(from) == 1; /* obsolete */
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bool recursive = readInt(from) == 1;
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string s = readString(from);
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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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SavingSourceAdapter 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 = dynamic_cast<LocalStore *>(store.get())
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->addToStoreFromDump(recursive ? savedNAR.s : 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>(from);
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startWork();
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Path path = store->addTextToStore(suffix, s, refs);
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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(from);
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bool sign = readInt(from) == 1;
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startWork();
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TunnelSink sink(to);
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store->exportPath(path, sign, 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(!trusted, source);
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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>(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(from);
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BasicDerivation drv;
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from >> 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(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(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>(from);
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options.ignoreLiveness = readInt(from);
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options.maxFreed = readLongLong(from);
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readInt(from); // obsolete field
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if (GET_PROTOCOL_MINOR(clientVersion) >= 5) {
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/* removed options */
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readInt(from);
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readInt(from);
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}
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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) != 0;
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settings.keepGoing = readInt(from) != 0;
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settings.set("build-fallback", readInt(from) ? "true" : "false");
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verbosity = (Verbosity) readInt(from);
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settings.set("build-max-jobs", std::to_string(readInt(from)));
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settings.set("build-max-silent-time", std::to_string(readInt(from)));
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if (GET_PROTOCOL_MINOR(clientVersion) >= 2)
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settings.useBuildHook = readInt(from) != 0;
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if (GET_PROTOCOL_MINOR(clientVersion) >= 4) {
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settings.buildVerbosity = (Verbosity) readInt(from);
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logType = (LogType) readInt(from);
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settings.printBuildTrace = readInt(from) != 0;
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}
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if (GET_PROTOCOL_MINOR(clientVersion) >= 6)
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settings.set("build-cores", std::to_string(readInt(from)));
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if (GET_PROTOCOL_MINOR(clientVersion) >= 10)
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settings.set("build-use-substitutes", readInt(from) ? "true" : "false");
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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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if (name == "build-timeout" || name == "use-ssh-substituter")
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settings.set(name, value);
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else
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settings.set(trusted ? name : "untrusted-" + name, value);
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}
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}
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settings.update();
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startWork();
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stopWork();
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break;
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}
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case wopQuerySubstitutablePathInfo: {
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Path path = absPath(readString(from));
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startWork();
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SubstitutablePathInfos infos;
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store->querySubstitutablePathInfos(singleton<PathSet>(path), infos);
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stopWork();
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SubstitutablePathInfos::iterator i = infos.find(path);
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if (i == infos.end())
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to << 0;
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else {
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to << 1 << i->second.deriver << i->second.references << i->second.downloadSize;
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if (GET_PROTOCOL_MINOR(clientVersion) >= 7)
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to << i->second.narSize;
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}
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break;
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}
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case wopQuerySubstitutablePathInfos: {
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PathSet paths = readStorePaths<PathSet>(from);
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startWork();
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SubstitutablePathInfos infos;
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store->querySubstitutablePathInfos(paths, infos);
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stopWork();
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to << infos.size();
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for (auto & i : infos) {
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to << i.first << i.second.deriver << i.second.references
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<< i.second.downloadSize << i.second.narSize;
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}
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break;
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}
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case wopQueryAllValidPaths: {
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startWork();
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PathSet paths = store->queryAllValidPaths();
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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 wopQueryFailedPaths: {
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startWork();
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PathSet paths = store->queryFailedPaths();
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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 wopClearFailedPaths: {
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PathSet paths = readStrings<PathSet>(from);
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startWork();
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store->clearFailedPaths(paths);
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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 wopQueryPathInfo: {
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Path path = readStorePath(from);
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startWork();
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ValidPathInfo info = store->queryPathInfo(path);
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stopWork();
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to << info.deriver << printHash(info.hash) << info.references
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<< info.registrationTime << info.narSize;
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break;
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}
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case wopOptimiseStore:
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startWork();
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store->optimiseStore();
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stopWork();
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to << 1;
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break;
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case wopVerifyStore: {
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bool checkContents = readInt(from) != 0;
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bool repair = readInt(from) != 0;
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startWork();
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if (repair && !trusted)
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throw Error("you are not privileged to repair paths");
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bool errors = store->verifyStore(checkContents, repair);
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stopWork();
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to << errors;
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break;
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}
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default:
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throw Error(format("invalid operation %1%") % op);
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}
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}
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static void processConnection(bool trusted)
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{
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MonitorFdHup monitor(from.fd);
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canSendStderr = false;
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_writeToStderr = tunnelStderr;
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/* Exchange the greeting. */
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unsigned int magic = readInt(from);
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if (magic != WORKER_MAGIC_1) throw Error("protocol mismatch");
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to << WORKER_MAGIC_2 << PROTOCOL_VERSION;
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to.flush();
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unsigned int clientVersion = readInt(from);
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if (GET_PROTOCOL_MINOR(clientVersion) >= 14 && readInt(from))
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setAffinityTo(readInt(from));
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bool reserveSpace = true;
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if (GET_PROTOCOL_MINOR(clientVersion) >= 11)
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reserveSpace = readInt(from) != 0;
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/* Send startup error messages to the client. */
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startWork();
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try {
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/* If we can't accept clientVersion, then throw an error
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*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)
|
||
|
||
#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 == -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 : 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.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 ? 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.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 = std::to_string(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);
|
||
});
|
||
}
|