Store parsed hashes in DerivationOutput

It's best to detect invalid data as soon as possible, with data types
that make storing it impossible.
This commit is contained in:
John Ericson 2020-03-22 23:43:07 -04:00
parent f5494d9442
commit 832bd534dc
8 changed files with 128 additions and 63 deletions

View file

@ -724,9 +724,9 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * *
auto outPath = state.store->makeFixedOutputPath(outputHashRecursive, h, drvName);
if (!jsonObject) drv.env["out"] = state.store->printStorePath(outPath);
drv.outputs.insert_or_assign("out", DerivationOutput(std::move(outPath),
(static_cast<bool>(outputHashRecursive) ? "r:" : "") + printHashType(h.type),
h.to_string(Base16, false)));
drv.outputs.insert_or_assign("out", DerivationOutput(
std::move(outPath),
FileSystemHash(outputHashRecursive, std::move(h))));
}
else {
@ -739,7 +739,7 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * *
for (auto & i : outputs) {
if (!jsonObject) drv.env[i] = "";
drv.outputs.insert_or_assign(i,
DerivationOutput(StorePath::dummy.clone(), "", ""));
DerivationOutput(StorePath::dummy.clone(), std::optional<FileSystemHash>()));
}
Hash h = hashDerivationModulo(*state.store, Derivation(drv), true);
@ -748,7 +748,7 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * *
auto outPath = state.store->makeOutputPath(i, h, drvName);
if (!jsonObject) drv.env[i] = state.store->printStorePath(outPath);
drv.outputs.insert_or_assign(i,
DerivationOutput(std::move(outPath), "", ""));
DerivationOutput(std::move(outPath), std::optional<FileSystemHash>()));
}
}

View file

@ -3647,10 +3647,7 @@ void DerivationGoal::registerOutputs()
if (fixedOutput) {
FileIngestionMethod recursive; Hash h;
i.second.parseHashInfo(recursive, h);
if (!static_cast<bool>(recursive)) {
if (i.second.hash->method == FileIngestionMethod::Flat) {
/* The output path should be a regular file without execute permission. */
if (!S_ISREG(st.st_mode) || (st.st_mode & S_IXUSR) != 0)
throw BuildError(
@ -3659,18 +3656,22 @@ void DerivationGoal::registerOutputs()
/* Check the hash. In hash mode, move the path produced by
the derivation to its content-addressed location. */
Hash h2 = static_cast<bool>(recursive) ? hashPath(h.type, actualPath).first : hashFile(h.type, actualPath);
Hash h2 = i.second.hash->method == FileIngestionMethod::Recursive
? hashPath(i.second.hash->hash.type, actualPath).first
: hashFile(i.second.hash->hash.type, actualPath);
auto dest = worker.store.makeFixedOutputPath(recursive, h2, i.second.path.name());
auto dest = worker.store.makeFixedOutputPath(i.second.hash->method, h2, i.second.path.name());
if (h != h2) {
if (i.second.hash->hash != h2) {
/* Throw an error after registering the path as
valid. */
worker.hashMismatch = true;
delayedException = std::make_exception_ptr(
BuildError("hash mismatch in fixed-output derivation '%s':\n wanted: %s\n got: %s",
worker.store.printStorePath(dest), h.to_string(SRI), h2.to_string(SRI)));
worker.store.printStorePath(dest),
i.second.hash->hash.to_string(SRI),
h2.to_string(SRI)));
Path actualDest = worker.store.Store::toRealPath(dest);
@ -3690,7 +3691,7 @@ void DerivationGoal::registerOutputs()
else
assert(worker.store.parseStorePath(path) == dest);
ca = makeFixedOutputCA(recursive, h2);
ca = makeFixedOutputCA(i.second.hash->method, h2);
}
/* Get rid of all weird permissions. This also checks that

View file

@ -8,22 +8,8 @@
namespace nix {
void DerivationOutput::parseHashInfo(FileIngestionMethod & recursive, Hash & hash) const
{
recursive = FileIngestionMethod::Flat;
string algo = hashAlgo;
if (string(algo, 0, 2) == "r:") {
recursive = FileIngestionMethod::Recursive;
algo = string(algo, 2);
}
HashType hashType = parseHashType(algo);
if (hashType == htUnknown)
throw Error("unknown hash algorithm '%s'", algo);
hash = Hash(this->hash, hashType);
std::string FileSystemHash::printMethodAlgo() const {
return makeFileIngestionPrefix(method) + printHashType(hash.type);
}
@ -35,7 +21,7 @@ BasicDerivation::BasicDerivation(const BasicDerivation & other)
{
for (auto & i : other.outputs)
outputs.insert_or_assign(i.first,
DerivationOutput(i.second.path.clone(), std::string(i.second.hashAlgo), std::string(i.second.hash)));
DerivationOutput(i.second.path.clone(), std::optional<FileSystemHash>(i.second.hash)));
for (auto & i : other.inputSrcs)
inputSrcs.insert(i.clone());
}
@ -142,6 +128,33 @@ static StringSet parseStrings(std::istream & str, bool arePaths)
}
static DerivationOutput parseDerivationOutput(const Store & store, istringstream_nocopy & str)
{
expect(str, ","); auto path = store.parseStorePath(parsePath(str));
expect(str, ","); auto hashAlgo = parseString(str);
expect(str, ","); const auto hash = parseString(str);
expect(str, ")");
auto method = FileIngestionMethod::Flat;
std::optional<FileSystemHash> fsh;
if (hashAlgo != "") {
if (string(hashAlgo, 0, 2) == "r:") {
method = FileIngestionMethod::Recursive;
hashAlgo = string(hashAlgo, 2);
}
const HashType hashType = parseHashType(hashAlgo);
if (hashType == htUnknown)
throw Error("unknown hash hashAlgorithm '%s'", hashAlgo);
fsh = FileSystemHash {
std::move(method),
Hash(hash, hashType),
};
}
return DerivationOutput(std::move(path), std::move(fsh));
}
static Derivation parseDerivation(const Store & store, const string & s)
{
Derivation drv;
@ -151,11 +164,7 @@ static Derivation parseDerivation(const Store & store, const string & s)
/* Parse the list of outputs. */
while (!endOfList(str)) {
expect(str, "("); std::string id = parseString(str);
expect(str, ","); auto path = store.parseStorePath(parsePath(str));
expect(str, ","); auto hashAlgo = parseString(str);
expect(str, ","); auto hash = parseString(str);
expect(str, ")");
drv.outputs.emplace(id, DerivationOutput(std::move(path), std::move(hashAlgo), std::move(hash)));
drv.outputs.emplace(id, parseDerivationOutput(store, str));
}
/* Parse the list of input derivations. */
@ -275,8 +284,9 @@ string Derivation::unparse(const Store & store, bool maskOutputs,
if (first) first = false; else s += ',';
s += '('; printUnquotedString(s, i.first);
s += ','; printUnquotedString(s, maskOutputs ? "" : store.printStorePath(i.second.path));
s += ','; printUnquotedString(s, i.second.hashAlgo);
s += ','; printUnquotedString(s, i.second.hash);
s += ','; printUnquotedString(s, i.second.hash ? i.second.hash->printMethodAlgo() : "");
s += ','; printUnquotedString(s,
i.second.hash ? i.second.hash->hash.to_string(Base16, false) : "");
s += ')';
}
@ -332,7 +342,7 @@ bool BasicDerivation::isFixedOutput() const
{
return outputs.size() == 1 &&
outputs.begin()->first == "out" &&
outputs.begin()->second.hash != "";
outputs.begin()->second.hash;
}
@ -365,8 +375,8 @@ Hash hashDerivationModulo(Store & store, const Derivation & drv, bool maskOutput
if (drv.isFixedOutput()) {
DerivationOutputs::const_iterator i = drv.outputs.begin();
return hashString(htSHA256, "fixed:out:"
+ i->second.hashAlgo + ":"
+ i->second.hash + ":"
+ i->second.hash->printMethodAlgo() + ":"
+ i->second.hash->hash.to_string(Base16, false) + ":"
+ store.printStorePath(i->second.path));
}
@ -409,6 +419,30 @@ StorePathSet BasicDerivation::outputPaths() const
return paths;
}
static DerivationOutput readDerivationOutput(Source & in, const Store & store)
{
auto path = store.parseStorePath(readString(in));
auto hashAlgo = readString(in);
const auto hash = readString(in);
auto method = FileIngestionMethod::Flat;
std::optional<FileSystemHash> fsh;
if (hashAlgo != "") {
if (string(hashAlgo, 0, 2) == "r:") {
method = FileIngestionMethod::Recursive;
hashAlgo = string(hashAlgo, 2);
}
HashType hashType = parseHashType(hashAlgo);
if (hashType == htUnknown)
throw Error("unknown hash hashAlgorithm '%s'", hashAlgo);
fsh = FileSystemHash {
std::move(method),
Hash(hash, hashType),
};
}
return DerivationOutput(std::move(path), std::move(fsh));
}
Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv)
{
@ -416,10 +450,8 @@ Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv)
auto nr = readNum<size_t>(in);
for (size_t n = 0; n < nr; n++) {
auto name = readString(in);
auto path = store.parseStorePath(readString(in));
auto hashAlgo = readString(in);
auto hash = readString(in);
drv.outputs.emplace(name, DerivationOutput(std::move(path), std::move(hashAlgo), std::move(hash)));
auto output = readDerivationOutput(in, store);
drv.outputs.emplace(name, output);
}
drv.inputSrcs = readStorePaths<StorePathSet>(store, in);
@ -441,7 +473,10 @@ void writeDerivation(Sink & out, const Store & store, const BasicDerivation & dr
{
out << drv.outputs.size();
for (auto & i : drv.outputs)
out << i.first << store.printStorePath(i.second.path) << i.second.hashAlgo << i.second.hash;
out << i.first
<< store.printStorePath(i.second.path)
<< i.second.hash->printMethodAlgo()
<< i.second.hash->hash.to_string(Base16, false);
writeStorePaths(store, out, drv.inputSrcs);
out << drv.platform << drv.builder << drv.args;
out << drv.env.size();

View file

@ -12,20 +12,31 @@ namespace nix {
/* Abstract syntax of derivations. */
/// Pair of a hash, and how the file system was ingested
struct FileSystemHash {
FileIngestionMethod method;
Hash hash;
FileSystemHash(FileIngestionMethod method, Hash hash)
: method(std::move(method))
, hash(std::move(hash))
{ }
FileSystemHash(const FileSystemHash &) = default;
FileSystemHash(FileSystemHash &&) = default;
FileSystemHash & operator = (const FileSystemHash &) = default;
std::string printMethodAlgo() const;
};
struct DerivationOutput
{
StorePath path;
std::string hashAlgo; /* hash used for expected hash computation */
std::string hash; /* expected hash, may be null */
DerivationOutput(StorePath && path, std::string && hashAlgo, std::string && hash)
std::optional<FileSystemHash> hash; /* hash used for expected hash computation */
DerivationOutput(StorePath && path, std::optional<FileSystemHash> && hash)
: path(std::move(path))
, hashAlgo(std::move(hashAlgo))
, hash(std::move(hash))
{ }
DerivationOutput(const DerivationOutput &) = default;
DerivationOutput(DerivationOutput &&) = default;
DerivationOutput & operator = (const DerivationOutput &) = default;
void parseHashInfo(FileIngestionMethod & recursive, Hash & hash) const;
};
typedef std::map<string, DerivationOutput> DerivationOutputs;

View file

@ -557,10 +557,12 @@ void LocalStore::checkDerivationOutputs(const StorePath & drvPath, const Derivat
if (out == drv.outputs.end())
throw Error("derivation '%s' does not have an output named 'out'", printStorePath(drvPath));
FileIngestionMethod recursive; Hash h;
out->second.parseHashInfo(recursive, h);
check(makeFixedOutputPath(recursive, h, drvName), out->second.path, "out");
check(
makeFixedOutputPath(
out->second.hash->method,
out->second.hash->hash,
drvName),
out->second.path, "out");
}
else {

View file

@ -171,18 +171,18 @@ static std::string makeType(
StorePath Store::makeFixedOutputPath(
FileIngestionMethod recursive,
FileIngestionMethod method,
const Hash & hash,
std::string_view name,
const StorePathSet & references,
bool hasSelfReference) const
{
if (hash.type == htSHA256 && recursive == FileIngestionMethod::Recursive) {
if (hash.type == htSHA256 && method == FileIngestionMethod::Recursive) {
return makeStorePath(makeType(*this, "source", references, hasSelfReference), hash, name);
} else {
assert(references.empty());
return makeStorePath("output:out", hashString(htSHA256,
"fixed:out:" + (static_cast<bool>(recursive) ? (string) "r:" : "") +
"fixed:out:" + makeFileIngestionPrefix(method) +
hash.to_string(Base16) + ":"), name);
}
}
@ -811,9 +811,22 @@ Strings ValidPathInfo::shortRefs() const
}
std::string makeFixedOutputCA(FileIngestionMethod recursive, const Hash & hash)
std::string makeFileIngestionPrefix(const FileIngestionMethod m) {
switch (m) {
case FileIngestionMethod::Flat:
return "";
case FileIngestionMethod::Recursive:
return "r:";
default:
throw Error("impossible, caught both cases");
}
}
std::string makeFixedOutputCA(FileIngestionMethod method, const Hash & hash)
{
return "fixed:" + (static_cast<bool>(recursive) ? (std::string) "r:" : "") + hash.to_string();
return "fixed:"
+ makeFileIngestionPrefix(method)
+ hash.to_string();
}

View file

@ -847,6 +847,9 @@ std::optional<ValidPathInfo> decodeValidPathInfo(
std::istream & str,
bool hashGiven = false);
/* Compute the prefix to the hash algorithm which indicates how the files were
ingested. */
std::string makeFileIngestionPrefix(const FileIngestionMethod m);
/* Compute the content-addressability assertion (ValidPathInfo::ca)
for paths created by makeFixedOutputPath() / addToStore(). */

View file

@ -69,9 +69,9 @@ struct CmdShowDerivation : InstallablesCommand
for (auto & output : drv.outputs) {
auto outputObj(outputsObj.object(output.first));
outputObj.attr("path", store->printStorePath(output.second.path));
if (output.second.hash != "") {
outputObj.attr("hashAlgo", output.second.hashAlgo);
outputObj.attr("hash", output.second.hash);
if (output.second.hash) {
outputObj.attr("hashAlgo", output.second.hash->printMethodAlgo());
outputObj.attr("hash", output.second.hash->hash.to_string(Base16, false));
}
}
}