diff options
Diffstat (limited to 'src/libstore/derivations.cc')
| -rw-r--r-- | src/libstore/derivations.cc | 499 |
1 files changed, 354 insertions, 145 deletions
diff --git a/src/libstore/derivations.cc b/src/libstore/derivations.cc index 42551ef6b..07b4e772b 100644 --- a/src/libstore/derivations.cc +++ b/src/libstore/derivations.cc @@ -4,16 +4,61 @@ #include "util.hh" #include "worker-protocol.hh" #include "fs-accessor.hh" -#include "istringstream_nocopy.hh" namespace nix { -const StorePath & BasicDerivation::findOutput(const string & id) const +std::optional<StorePath> DerivationOutput::path(const Store & store, std::string_view drvName, std::string_view outputName) const { - auto i = outputs.find(id); - if (i == outputs.end()) - throw Error("derivation has no output '%s'", id); - return i->second.path; + return std::visit(overloaded { + [](DerivationOutputInputAddressed doi) -> std::optional<StorePath> { + return { doi.path }; + }, + [&](DerivationOutputCAFixed dof) -> std::optional<StorePath> { + return { + dof.path(store, drvName, outputName) + }; + }, + [](DerivationOutputCAFloating dof) -> std::optional<StorePath> { + return std::nullopt; + }, + }, output); +} + + +StorePath DerivationOutputCAFixed::path(const Store & store, std::string_view drvName, std::string_view outputName) const { + return store.makeFixedOutputPath( + hash.method, hash.hash, + outputPathName(drvName, outputName)); +} + + +bool derivationIsCA(DerivationType dt) { + switch (dt) { + case DerivationType::InputAddressed: return false; + case DerivationType::CAFixed: return true; + case DerivationType::CAFloating: return true; + }; + // Since enums can have non-variant values, but making a `default:` would + // disable exhaustiveness warnings. + assert(false); +} + +bool derivationIsFixed(DerivationType dt) { + switch (dt) { + case DerivationType::InputAddressed: return false; + case DerivationType::CAFixed: return true; + case DerivationType::CAFloating: return false; + }; + assert(false); +} + +bool derivationIsImpure(DerivationType dt) { + switch (dt) { + case DerivationType::InputAddressed: return false; + case DerivationType::CAFixed: return true; + case DerivationType::CAFloating: return false; + }; + assert(false); } @@ -23,8 +68,8 @@ bool BasicDerivation::isBuiltin() const } -StorePath writeDerivation(ref<Store> store, - const Derivation & drv, std::string_view name, RepairFlag repair) +StorePath writeDerivation(Store & store, + const Derivation & drv, RepairFlag repair, bool readOnly) { auto references = drv.inputSrcs; for (auto & i : drv.inputDrvs) @@ -32,11 +77,11 @@ StorePath writeDerivation(ref<Store> store, /* Note that the outputs of a derivation are *not* references (that can be missing (of course) and should not necessarily be held during a garbage collection). */ - auto suffix = std::string(name) + drvExtension; - auto contents = drv.unparse(*store, false); - return settings.readOnlyMode - ? store->computeStorePathForText(suffix, contents, references) - : store->addTextToStore(suffix, contents, references, repair); + auto suffix = std::string(drv.name) + drvExtension; + auto contents = drv.unparse(store, false); + return readOnly || settings.readOnlyMode + ? store.computeStorePathForText(suffix, contents, references) + : store.addTextToStore(suffix, contents, references, repair); } @@ -68,12 +113,15 @@ static string parseString(std::istream & str) return res; } +static void validatePath(std::string_view s) { + if (s.size() == 0 || s[0] != '/') + throw FormatError("bad path '%1%' in derivation", s); +} static Path parsePath(std::istream & str) { - string s = parseString(str); - if (s.size() == 0 || s[0] != '/') - throw FormatError("bad path '%1%' in derivation", s); + auto s = parseString(str); + validatePath(s); return s; } @@ -101,38 +149,63 @@ static StringSet parseStrings(std::istream & str, bool arePaths) } -static DerivationOutput parseDerivationOutput(const Store & store, istringstream_nocopy & str) +static DerivationOutput parseDerivationOutput(const Store & store, + std::string_view pathS, std::string_view hashAlgo, std::string_view hash) { - expect(str, ","); auto path = store.parseStorePath(parsePath(str)); - expect(str, ","); auto hashAlgo = parseString(str); - expect(str, ","); const auto hash = parseString(str); - expect(str, ")"); - - std::optional<FixedOutputHash> fsh; if (hashAlgo != "") { auto method = FileIngestionMethod::Flat; if (string(hashAlgo, 0, 2) == "r:") { method = FileIngestionMethod::Recursive; - hashAlgo = string(hashAlgo, 2); + hashAlgo = hashAlgo.substr(2); + } + const auto hashType = parseHashType(hashAlgo); + if (hash != "") { + validatePath(pathS); + return DerivationOutput { + .output = DerivationOutputCAFixed { + .hash = FixedOutputHash { + .method = std::move(method), + .hash = Hash::parseNonSRIUnprefixed(hash, hashType), + }, + }, + }; + } else { + settings.requireExperimentalFeature("ca-derivations"); + assert(pathS == ""); + return DerivationOutput { + .output = DerivationOutputCAFloating { + .method = std::move(method), + .hashType = std::move(hashType), + }, + }; } - const HashType hashType = parseHashType(hashAlgo); - fsh = FixedOutputHash { - .method = std::move(method), - .hash = Hash(hash, hashType), + } else { + validatePath(pathS); + return DerivationOutput { + .output = DerivationOutputInputAddressed { + .path = store.parseStorePath(pathS), + } }; } +} - return DerivationOutput { - .path = std::move(path), - .hash = std::move(fsh), - }; +static DerivationOutput parseDerivationOutput(const Store & store, std::istringstream & str) +{ + expect(str, ","); const auto pathS = parseString(str); + expect(str, ","); const auto hashAlgo = parseString(str); + expect(str, ","); const auto hash = parseString(str); + expect(str, ")"); + + return parseDerivationOutput(store, pathS, hashAlgo, hash); } -static Derivation parseDerivation(const Store & store, const string & s) +Derivation parseDerivation(const Store & store, std::string && s, std::string_view name) { Derivation drv; - istringstream_nocopy str(s); + drv.name = name; + + std::istringstream str(std::move(s)); expect(str, "Derive(["); /* Parse the list of outputs. */ @@ -175,34 +248,6 @@ static Derivation parseDerivation(const Store & store, const string & s) } -Derivation readDerivation(const Store & store, const Path & drvPath) -{ - try { - return parseDerivation(store, readFile(drvPath)); - } catch (FormatError & e) { - throw Error("error parsing derivation '%1%': %2%", drvPath, e.msg()); - } -} - - -Derivation Store::derivationFromPath(const StorePath & drvPath) -{ - ensurePath(drvPath); - return readDerivation(drvPath); -} - - -Derivation Store::readDerivation(const StorePath & drvPath) -{ - auto accessor = getFSAccessor(); - try { - return parseDerivation(*this, accessor->readFile(printStorePath(drvPath))); - } catch (FormatError & e) { - throw Error("error parsing derivation '%s': %s", printStorePath(drvPath), e.msg()); - } -} - - static void printString(string & res, std::string_view s) { char buf[s.size() * 2 + 2]; @@ -264,10 +309,23 @@ string Derivation::unparse(const Store & store, bool maskOutputs, for (auto & i : outputs) { 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.hash ? i.second.hash->printMethodAlgo() : ""); - s += ','; printUnquotedString(s, - i.second.hash ? i.second.hash->hash.to_string(Base16, false) : ""); + std::visit(overloaded { + [&](DerivationOutputInputAddressed doi) { + s += ','; printUnquotedString(s, maskOutputs ? "" : store.printStorePath(doi.path)); + s += ','; printUnquotedString(s, ""); + s += ','; printUnquotedString(s, ""); + }, + [&](DerivationOutputCAFixed dof) { + s += ','; printUnquotedString(s, maskOutputs ? "" : store.printStorePath(dof.path(store, name, i.first))); + s += ','; printUnquotedString(s, dof.hash.printMethodAlgo()); + s += ','; printUnquotedString(s, dof.hash.hash.to_string(Base16, false)); + }, + [&](DerivationOutputCAFloating dof) { + s += ','; printUnquotedString(s, ""); + s += ','; printUnquotedString(s, makeFileIngestionPrefix(dof.method) + printHashType(dof.hashType)); + s += ','; printUnquotedString(s, ""); + }, + }, i.second.output); s += ')'; } @@ -319,59 +377,144 @@ bool isDerivation(const string & fileName) } -bool BasicDerivation::isFixedOutput() const +std::string outputPathName(std::string_view drvName, std::string_view outputName) { + std::string res { drvName }; + if (outputName != "out") { + res += "-"; + res += outputName; + } + return res; +} + + +DerivationType BasicDerivation::type() const { - return outputs.size() == 1 && - outputs.begin()->first == "out" && - outputs.begin()->second.hash; + std::set<std::string_view> inputAddressedOutputs, fixedCAOutputs, floatingCAOutputs; + std::optional<HashType> floatingHashType; + for (auto & i : outputs) { + std::visit(overloaded { + [&](DerivationOutputInputAddressed _) { + inputAddressedOutputs.insert(i.first); + }, + [&](DerivationOutputCAFixed _) { + fixedCAOutputs.insert(i.first); + }, + [&](DerivationOutputCAFloating dof) { + floatingCAOutputs.insert(i.first); + if (!floatingHashType) { + floatingHashType = dof.hashType; + } else { + if (*floatingHashType != dof.hashType) + throw Error("All floating outputs must use the same hash type"); + } + }, + }, i.second.output); + } + + if (inputAddressedOutputs.empty() && fixedCAOutputs.empty() && floatingCAOutputs.empty()) { + throw Error("Must have at least one output"); + } else if (! inputAddressedOutputs.empty() && fixedCAOutputs.empty() && floatingCAOutputs.empty()) { + return DerivationType::InputAddressed; + } else if (inputAddressedOutputs.empty() && ! fixedCAOutputs.empty() && floatingCAOutputs.empty()) { + if (fixedCAOutputs.size() > 1) + // FIXME: Experimental feature? + throw Error("Only one fixed output is allowed for now"); + if (*fixedCAOutputs.begin() != "out") + throw Error("Single fixed output must be named \"out\""); + return DerivationType::CAFixed; + } else if (inputAddressedOutputs.empty() && fixedCAOutputs.empty() && ! floatingCAOutputs.empty()) { + return DerivationType::CAFloating; + } else { + throw Error("Can't mix derivation output types"); + } } DrvHashes drvHashes; +/* pathDerivationModulo and hashDerivationModulo are mutually recursive + */ + +/* Look up the derivation by value and memoize the + `hashDerivationModulo` call. + */ +static const DrvHashModulo & pathDerivationModulo(Store & store, const StorePath & drvPath) +{ + auto h = drvHashes.find(drvPath); + if (h == drvHashes.end()) { + assert(store.isValidPath(drvPath)); + // Cache it + h = drvHashes.insert_or_assign( + drvPath, + hashDerivationModulo( + store, + store.readDerivation(drvPath), + false)).first; + } + return h->second; +} -/* Returns the hash of a derivation modulo fixed-output - subderivations. A fixed-output derivation is a derivation with one - output (`out') for which an expected hash and hash algorithm are - specified (using the `outputHash' and `outputHashAlgo' - attributes). We don't want changes to such derivations to - propagate upwards through the dependency graph, changing output - paths everywhere. - - For instance, if we change the url in a call to the `fetchurl' - function, we do not want to rebuild everything depending on it - (after all, (the hash of) the file being downloaded is unchanged). - So the *output paths* should not change. On the other hand, the - *derivation paths* should change to reflect the new dependency - graph. - - That's what this function does: it returns a hash which is just the - hash of the derivation ATerm, except that any input derivation - paths have been replaced by the result of a recursive call to this - function, and that for fixed-output derivations we return a hash of - its output path. */ -Hash hashDerivationModulo(Store & store, const Derivation & drv, bool maskOutputs) +/* See the header for interface details. These are the implementation details. + + For fixed-output derivations, each hash in the map is not the + corresponding output's content hash, but a hash of that hash along + with other constant data. The key point is that the value is a pure + function of the output's contents, and there are no preimage attacks + either spoofing an output's contents for a derivation, or + spoofing a derivation for an output's contents. + + For regular derivations, it looks up each subderivation from its hash + and recurs. If the subderivation is also regular, it simply + substitutes the derivation path with its hash. If the subderivation + is fixed-output, however, it takes each output hash and pretends it + is a derivation hash producing a single "out" output. This is so we + don't leak the provenance of fixed outputs, reducing pointless cache + misses as the build itself won't know this. + */ +DrvHashModulo hashDerivationModulo(Store & store, const Derivation & drv, bool maskOutputs) { /* Return a fixed hash for fixed-output derivations. */ - if (drv.isFixedOutput()) { - DerivationOutputs::const_iterator i = drv.outputs.begin(); - return hashString(htSHA256, "fixed:out:" - + i->second.hash->printMethodAlgo() + ":" - + i->second.hash->hash.to_string(Base16, false) + ":" - + store.printStorePath(i->second.path)); + switch (drv.type()) { + case DerivationType::CAFloating: + throw Error("Regular input-addressed derivations are not yet allowed to depend on CA derivations"); + case DerivationType::CAFixed: { + std::map<std::string, Hash> outputHashes; + for (const auto & i : drv.outputs) { + auto & dof = std::get<DerivationOutputCAFixed>(i.second.output); + auto hash = hashString(htSHA256, "fixed:out:" + + dof.hash.printMethodAlgo() + ":" + + dof.hash.hash.to_string(Base16, false) + ":" + + store.printStorePath(dof.path(store, drv.name, i.first))); + outputHashes.insert_or_assign(i.first, std::move(hash)); + } + return outputHashes; + } + case DerivationType::InputAddressed: + break; } /* For other derivations, replace the inputs paths with recursive - calls to this function.*/ + calls to this function. */ std::map<std::string, StringSet> inputs2; for (auto & i : drv.inputDrvs) { - auto h = drvHashes.find(i.first); - if (h == drvHashes.end()) { - assert(store.isValidPath(i.first)); - h = drvHashes.insert_or_assign(i.first, hashDerivationModulo(store, - store.readDerivation(i.first), false)).first; - } - inputs2.insert_or_assign(h->second.to_string(Base16, false), i.second); + const auto & res = pathDerivationModulo(store, i.first); + std::visit(overloaded { + // Regular non-CA derivation, replace derivation + [&](Hash drvHash) { + inputs2.insert_or_assign(drvHash.to_string(Base16, false), i.second); + }, + // CA derivation's output hashes + [&](CaOutputHashes outputHashes) { + std::set<std::string> justOut = { "out" }; + for (auto & output : i.second) { + /* Put each one in with a single "out" output.. */ + const auto h = outputHashes.at(output); + inputs2.insert_or_assign( + h.to_string(Base16, false), + justOut); + } + }, + }, res); } return hashString(htSHA256, drv.unparse(store, maskOutputs, &inputs2)); @@ -392,38 +535,13 @@ bool wantOutput(const string & output, const std::set<string> & wanted) } -StorePathSet BasicDerivation::outputPaths() const -{ - StorePathSet paths; - for (auto & i : outputs) - paths.insert(i.second.path); - return paths; -} - static DerivationOutput readDerivationOutput(Source & in, const Store & store) { - auto path = store.parseStorePath(readString(in)); - auto hashAlgo = readString(in); - auto hash = readString(in); + const auto pathS = readString(in); + const auto hashAlgo = readString(in); + const auto hash = readString(in); - std::optional<FixedOutputHash> fsh; - if (hashAlgo != "") { - auto method = FileIngestionMethod::Flat; - if (string(hashAlgo, 0, 2) == "r:") { - method = FileIngestionMethod::Recursive; - hashAlgo = string(hashAlgo, 2); - } - auto hashType = parseHashType(hashAlgo); - fsh = FixedOutputHash { - .method = std::move(method), - .hash = Hash(hash, hashType), - }; - } - - return DerivationOutput { - .path = std::move(path), - .hash = std::move(fsh), - }; + return parseDerivationOutput(store, pathS, hashAlgo, hash); } StringSet BasicDerivation::outputNames() const @@ -434,9 +552,30 @@ StringSet BasicDerivation::outputNames() const return names; } +DerivationOutputsAndOptPaths BasicDerivation::outputsAndOptPaths(const Store & store) const { + DerivationOutputsAndOptPaths outsAndOptPaths; + for (auto output : outputs) + outsAndOptPaths.insert(std::make_pair( + output.first, + std::make_pair(output.second, output.second.path(store, name, output.first)) + ) + ); + return outsAndOptPaths; +} + +std::string_view BasicDerivation::nameFromPath(const StorePath & drvPath) { + auto nameWithSuffix = drvPath.name(); + constexpr std::string_view extension = ".drv"; + assert(hasSuffix(nameWithSuffix, extension)); + nameWithSuffix.remove_suffix(extension.size()); + return nameWithSuffix; +} + -Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv) +Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv, std::string_view name) { + drv.name = name; + drv.outputs.clear(); auto nr = readNum<size_t>(in); for (size_t n = 0; n < nr; n++) { @@ -445,7 +584,7 @@ Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv) drv.outputs.emplace(std::move(name), std::move(output)); } - drv.inputSrcs = readStorePaths<StorePathSet>(store, in); + drv.inputSrcs = worker_proto::read(store, in, Phantom<StorePathSet> {}); in >> drv.platform >> drv.builder; drv.args = readStrings<Strings>(in); @@ -464,16 +603,26 @@ 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); - if (i.second.hash) { - out << i.second.hash->printMethodAlgo() - << i.second.hash->hash.to_string(Base16, false); - } else { - out << "" << ""; - } + out << i.first; + std::visit(overloaded { + [&](DerivationOutputInputAddressed doi) { + out << store.printStorePath(doi.path) + << "" + << ""; + }, + [&](DerivationOutputCAFixed dof) { + out << store.printStorePath(dof.path(store, drv.name, i.first)) + << dof.hash.printMethodAlgo() + << dof.hash.hash.to_string(Base16, false); + }, + [&](DerivationOutputCAFloating dof) { + out << "" + << (makeFileIngestionPrefix(dof.method) + printHashType(dof.hashType)) + << ""; + }, + }, i.second.output); } - writeStorePaths(store, out, drv.inputSrcs); + worker_proto::write(store, out, drv.inputSrcs); out << drv.platform << drv.builder << drv.args; out << drv.env.size(); for (auto & i : drv.env) @@ -487,5 +636,65 @@ std::string hashPlaceholder(const std::string & outputName) return "/" + hashString(htSHA256, "nix-output:" + outputName).to_string(Base32, false); } +std::string downstreamPlaceholder(const Store & store, const StorePath & drvPath, std::string_view outputName) +{ + auto drvNameWithExtension = drvPath.name(); + auto drvName = drvNameWithExtension.substr(0, drvNameWithExtension.size() - 4); + auto clearText = "nix-upstream-output:" + std::string { drvPath.hashPart() } + ":" + outputPathName(drvName, outputName); + return "/" + hashString(htSHA256, clearText).to_string(Base32, false); +} + + +// N.B. Outputs are left unchanged +static void rewriteDerivation(Store & store, BasicDerivation & drv, const StringMap & rewrites) { + + debug("Rewriting the derivation"); + + for (auto &rewrite: rewrites) { + debug("rewriting %s as %s", rewrite.first, rewrite.second); + } + + drv.builder = rewriteStrings(drv.builder, rewrites); + for (auto & arg: drv.args) { + arg = rewriteStrings(arg, rewrites); + } + + StringPairs newEnv; + for (auto & envVar: drv.env) { + auto envName = rewriteStrings(envVar.first, rewrites); + auto envValue = rewriteStrings(envVar.second, rewrites); + newEnv.emplace(envName, envValue); + } + drv.env = newEnv; +} + + +Sync<DrvPathResolutions> drvPathResolutions; + +std::optional<BasicDerivation> Derivation::tryResolve(Store & store) { + BasicDerivation resolved { *this }; + + // Input paths that we'll want to rewrite in the derivation + StringMap inputRewrites; + + for (auto & input : inputDrvs) { + auto inputDrvOutputs = store.queryPartialDerivationOutputMap(input.first); + StringSet newOutputNames; + for (auto & outputName : input.second) { + auto actualPathOpt = inputDrvOutputs.at(outputName); + if (!actualPathOpt) + return std::nullopt; + auto actualPath = *actualPathOpt; + inputRewrites.emplace( + downstreamPlaceholder(store, input.first, outputName), + store.printStorePath(actualPath)); + resolved.inputSrcs.insert(std::move(actualPath)); + } + } + + rewriteDerivation(store, resolved, inputRewrites); + + return resolved; +} } |