wroclaw-git-backups/nix
1
0
Fork 0
mirror of https://github.com/NixOS/nix synced 2025-06-25 02:21:16 +02:00
Code Activity

fix: Handle symlinks and FIFOs in nix hash where possible

Browse source 
Fixes https://github.com/NixOS/nix/issues/11756
Fixes https://github.com/NixOS/nix/issues/11681
This commit is contained in:
Robert Hensing 2024-12-13 17:21:56 +01:00 • committed by Mic92
parent 69853c067c
commit 36563c69a4
3 changed files with 45 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

2
src/libutil/posix-source-accessor.hh
View file

@ -43,7 +43,7 @@ struct PosixSourceAccessor : virtual SourceAccessor
std::optional<std::filesystem::path> getPhysicalPath(const CanonPath & path) override;
/**
* Create a `PosixSourceAccessor` and `CanonPath` corresponding to
* Create a `PosixSourceAccessor` and `SourcePath` corresponding to
* some native path.
*
* The `PosixSourceAccessor` is rooted as far up the tree as

23
src/nix/hash.cc
View file

@ -87,18 +87,35 @@ struct CmdHashBase : Command
return std::make_unique<HashSink>(hashAlgo);
};
auto path2 = PosixSourceAccessor::createAtRoot(path);
auto makeSourcePath = [&]() -> SourcePath {
return PosixSourceAccessor::createAtRoot(makeParentCanonical(path));
};
Hash h { HashAlgorithm::SHA256 }; // throwaway def to appease C++
switch (mode) {
case FileIngestionMethod::Flat:
{
// While usually we could use the some code as for NixArchive,
// the Flat method needs to support FIFOs, such as those
// produced by bash process substitution, e.g.:
// nix hash --mode flat <(echo hi)
// Also symlinks semantics are unambiguous in the flat case,
// so we don't need to go low-level, or reject symlink `path`s.
auto hashSink = makeSink();
readFile(path, *hashSink);
h = hashSink->finish().first;
break;
}
case FileIngestionMethod::NixArchive:
{
auto sourcePath = makeSourcePath();
auto hashSink = makeSink();
dumpPath(path2, *hashSink, (FileSerialisationMethod) mode);
dumpPath(sourcePath, *hashSink, (FileSerialisationMethod) mode);
h = hashSink->finish().first;
break;
}
case FileIngestionMethod::Git: {
auto sourcePath = makeSourcePath();
std::function<git::DumpHook> hook;
hook = [&](const SourcePath & path) -> git::TreeEntry {
auto hashSink = makeSink();
@ -109,7 +126,7 @@ struct CmdHashBase : Command
.hash = hash,
};
};
h = hook(path2).hash;
h = hook(sourcePath).hash;
break;
}
}

24
tests/functional/hash-path.sh
View file

@ -92,3 +92,27 @@ try2 md5 "20f3ffe011d4cfa7d72bfabef7882836"
rm "$TEST_ROOT/hash-path/hello"
ln -s x "$TEST_ROOT/hash-path/hello"
try2 md5 "f78b733a68f5edbdf9413899339eaa4a"
# Flat mode supports process substitution
h=$(nix hash path --mode flat --type sha256 --base32 <(printf "SMASH THE STATE"))
[[ 0d9n3r2i4m1zgy0wpqbsyabsfzgs952066bfp8gwvcg4mkr4r5g8 == "$h" ]]
# Flat mode supports process substitution (hash file)
h=$(nix hash file --type sha256 --base32 <(printf "SMASH THE STATE"))
[[ 0d9n3r2i4m1zgy0wpqbsyabsfzgs952066bfp8gwvcg4mkr4r5g8 == "$h" ]]
# Symlinks in the ancestry are ok and don't affect the result
mkdir -p "$TEST_ROOT/simple" "$TEST_ROOT/try/to/mess/with/it"
echo hi > "$TEST_ROOT/simple/hi"
ln -s "$TEST_ROOT/simple" "$TEST_ROOT/try/to/mess/with/it/simple-link"
h=$(nix hash path --type sha256 --base32 "$TEST_ROOT/simple/hi")
[[ 1xmr8jicvzszfzpz46g37mlpvbzjl2wpwvl2b05psipssyp1sm8h == "$h" ]]
h=$(nix hash path --type sha256 --base32 "$TEST_ROOT/try/to/mess/with/it/simple-link/hi")
[[ 1xmr8jicvzszfzpz46g37mlpvbzjl2wpwvl2b05psipssyp1sm8h == "$h" ]]
# nix hash --mode nar does not canonicalize a symlink argument.
# Otherwise it can't generate a NAR whose root is a symlink.
# If you want to follow the symlink, pass $(realpath -s ...) instead.
ln -s /non-existent-48cujwe8ndf4as0bne "$TEST_ROOT/symlink-to-nowhere"
h=$(nix hash path --mode nar --type sha256 --base32 "$TEST_ROOT/symlink-to-nowhere")
[[ 1bl5ry3x1fcbwgr5c2x50bn572iixh4j1p6ax5isxly2ddgn8pbp == "$h" ]] # manually verified hash