# Checks derivation meta and attrs for problems (like brokenness,
# licenses, etc).
{ lib, config, hostPlatform }:
let
# If we're in hydra, we can dispense with the more verbose error
# messages and make problems easier to spot.
inHydra = config.inHydra or false;
getName = attrs: attrs.name or ("${attrs.pname or "«name-missing»"}-${attrs.version or "«version-missing»"}");
# See discussion at https://github.com/NixOS/nixpkgs/pull/25304#issuecomment-298385426
# for why this defaults to false, but I (@copumpkin) want to default it to true soon.
shouldCheckMeta = config.checkMeta or false;
allowUnfree = config.allowUnfree or false
|| builtins.getEnv "NIXPKGS_ALLOW_UNFREE" == "1";
whitelist = config.whitelistedLicenses or [];
blacklist = config.blacklistedLicenses or [];
onlyLicenses = list:
lib.lists.all (license:
let l = lib.licenses.${license.shortName or "BROKEN"} or false; in
if license == l then true else
throw ''‘${showLicense license}’ is not an attribute of lib.licenses''
) list;
areLicenseListsValid =
if lib.mutuallyExclusive whitelist blacklist then
assert onlyLicenses whitelist; assert onlyLicenses blacklist; true
else
throw "whitelistedLicenses and blacklistedLicenses are not mutually exclusive.";
hasLicense = attrs:
attrs ? meta.license;
hasWhitelistedLicense = assert areLicenseListsValid; attrs:
hasLicense attrs && lib.lists.any (l: builtins.elem l whitelist) (lib.lists.toList attrs.meta.license);
hasBlacklistedLicense = assert areLicenseListsValid; attrs:
hasLicense attrs && lib.lists.any (l: builtins.elem l blacklist) (lib.lists.toList attrs.meta.license);
allowBroken = config.allowBroken or false
|| builtins.getEnv "NIXPKGS_ALLOW_BROKEN" == "1";
allowUnsupportedSystem = config.allowUnsupportedSystem or false
|| builtins.getEnv "NIXPKGS_ALLOW_UNSUPPORTED_SYSTEM" == "1";
isUnfree = licenses: lib.lists.any (l: !l.free or true) licenses;
hasUnfreeLicense = attrs:
hasLicense attrs &&
isUnfree (lib.lists.toList attrs.meta.license);
isMarkedBroken = attrs: attrs.meta.broken or false;
hasUnsupportedPlatform = attrs:
(!lib.lists.elem hostPlatform.system (attrs.meta.platforms or lib.platforms.all) ||
lib.lists.elem hostPlatform.system (attrs.meta.badPlatforms or []));
isMarkedInsecure = attrs: (attrs.meta.knownVulnerabilities or []) != [];
# Alow granular checks to allow only some unfree packages
# Example:
# {pkgs, ...}:
# {
# allowUnfree = false;
# allowUnfreePredicate = (x: pkgs.lib.hasPrefix "flashplayer-" x.name);
# }
allowUnfreePredicate = config.allowUnfreePredicate or (x: false);
# Check whether unfree packages are allowed and if not, whether the
# package has an unfree license and is not explicitely allowed by the
# `allowUnfreePredicate` function.
hasDeniedUnfreeLicense = attrs:
hasUnfreeLicense attrs &&
!allowUnfree &&
!allowUnfreePredicate attrs;
allowInsecureDefaultPredicate = x: builtins.elem (getName x) (config.permittedInsecurePackages or []);
allowInsecurePredicate = x: (config.allowInsecurePredicate or allowInsecureDefaultPredicate) x;
hasAllowedInsecure = attrs:
!(isMarkedInsecure attrs) ||
allowInsecurePredicate attrs ||
builtins.getEnv "NIXPKGS_ALLOW_INSECURE" == "1";
showLicense = license: toString (map (l: l.shortName or "unknown") (lib.lists.toList license));
pos_str = meta: meta.position or "«unknown-file»";
remediation = {
unfree = remediate_whitelist "Unfree" remediate_unfree_predicate;
broken = remediate_whitelist "Broken" (x: "");
unsupported = remediate_whitelist "UnsupportedSystem" (x: "");
blacklisted = x: "";
insecure = remediate_insecure;
broken-outputs = remediateOutputsToInstall;
unknown-meta = x: "";
};
remediation_env_var = allow_attr: {
Unfree = "NIXPKGS_ALLOW_UNFREE";
Broken = "NIXPKGS_ALLOW_BROKEN";
UnsupportedSystem = "NIXPKGS_ALLOW_UNSUPPORTED_SYSTEM";
}.${allow_attr};
remediation_phrase = allow_attr: {
Unfree = "unfree packages";
Broken = "broken packages";
UnsupportedSystem = "packages that are unsupported for this system";
}.${allow_attr};
remediate_unfree_predicate = attrs:
''
Alternatively you can configure a predicate to whitelist specific packages:
{ nixpkgs.config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [
"${lib.getName attrs}"
];
}
'';
remediate_whitelist = allow_attr: rebuild_amendment: attrs:
''
a) To temporarily allow ${remediation_phrase allow_attr}, you can use an environment variable
for a single invocation of the nix tools.
$ export ${remediation_env_var allow_attr}=1
b) For `nixos-rebuild` you can set
{ nixpkgs.config.allow${allow_attr} = true; }
in configuration.nix to override this.
${rebuild_amendment attrs}
c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
{ allow${allow_attr} = true; }
to ~/.config/nixpkgs/config.nix.
'';
remediate_insecure = attrs:
''
Known issues:
'' + (lib.concatStrings (map (issue: " - ${issue}\n") attrs.meta.knownVulnerabilities)) + ''
You can install it anyway by whitelisting this package, using the
following methods:
a) To temporarily allow all insecure packages, you can use an environment
variable for a single invocation of the nix tools:
$ export NIXPKGS_ALLOW_INSECURE=1
b) for `nixos-rebuild` you can add ‘${getName attrs}’ to
`nixpkgs.config.permittedInsecurePackages` in the configuration.nix,
like so:
{
nixpkgs.config.permittedInsecurePackages = [
"${getName attrs}"
];
}
c) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
‘${getName attrs}’ to `permittedInsecurePackages` in
~/.config/nixpkgs/config.nix, like so:
{
permittedInsecurePackages = [
"${getName attrs}"
];
}
'';
remediateOutputsToInstall = attrs: let
expectedOutputs = attrs.meta.outputsToInstall or [];
actualOutputs = attrs.outputs or [ "out" ];
missingOutputs = builtins.filter (output: ! builtins.elem output actualOutputs) expectedOutputs;
in ''
The package ${getName attrs} has set meta.outputsToInstall to: ${builtins.concatStringsSep ", " expectedOutputs}
however ${getName attrs} only has the outputs: ${builtins.concatStringsSep ", " actualOutputs}
and is missing the following ouputs:
${lib.concatStrings (builtins.map (output: " - ${output}\n") missingOutputs)}
'';
handleEvalIssue = { meta, attrs }: { reason , errormsg ? "" }:
let
msg = if inHydra
then "Failed to evaluate ${getName attrs}: «${reason}»: ${errormsg}"
else ''
Package ‘${getName attrs}’ in ${pos_str meta} ${errormsg}, refusing to evaluate.
'' + (builtins.getAttr reason remediation) attrs;
handler = if config ? handleEvalIssue
then config.handleEvalIssue reason
else throw;
in handler msg;
metaTypes = with lib.types; rec {
# These keys are documented
description = str;
longDescription = str;
branch = str;
homepage = either (listOf str) str;
downloadPage = str;
changelog = either (listOf str) str;
license = either (listOf lib.types.attrs) (either lib.types.attrs str);
maintainers = listOf (attrsOf str);
priority = int;
platforms = listOf str;
hydraPlatforms = listOf str;
broken = bool;
unfree = bool;
unsupported = bool;
insecure = bool;
# TODO: refactor once something like Profpatsch's types-simple will land
# This is currently dead code due to https://github.com/NixOS/nix/issues/2532
tests = attrsOf (mkOptionType {
name = "test";
check = x: x == {} || ( # Accept {} for tests that are unsupported
isDerivation x &&
x ? meta.timeout
);
merge = lib.options.mergeOneOption;
});
timeout = int;
# Weirder stuff that doesn't appear in the documentation?
knownVulnerabilities = listOf str;
name = str;
version = str;
tag = str;
updateWalker = bool;
executables = listOf str;
outputsToInstall = listOf str;
position = str;
available = bool;
repositories = attrsOf str;
isBuildPythonPackage = platforms;
schedulingPriority = int;
downloadURLRegexp = str;
isFcitxEngine = bool;
isIbusEngine = bool;
isGutenprint = bool;
badPlatforms = platforms;
};
checkMetaAttr = k: v:
if metaTypes?${k} then
if metaTypes.${k}.check v then null else "key '${k}' has a value ${toString v} of an invalid type ${builtins.typeOf v}; expected ${metaTypes.${k}.description}"
else "key '${k}' is unrecognized; expected one of: \n\t [${lib.concatMapStringsSep ", " (x: "'${x}'") (lib.attrNames metaTypes)}]";
checkMeta = meta: if shouldCheckMeta then lib.remove null (lib.mapAttrsToList checkMetaAttr meta) else [];
checkOutputsToInstall = attrs: let
expectedOutputs = attrs.meta.outputsToInstall or [];
actualOutputs = attrs.outputs or [ "out" ];
missingOutputs = builtins.filter (output: ! builtins.elem output actualOutputs) expectedOutputs;
in if shouldCheckMeta
then builtins.length missingOutputs > 0
else false;
# Check if a derivation is valid, that is whether it passes checks for
# e.g brokenness or license.
#
# Return { valid: Bool } and additionally
# { reason: String; errormsg: String } if it is not valid, where
# reason is one of "unfree", "blacklisted", "broken", "insecure", ...
# Along with a boolean flag for each reason
checkValidity = attrs:
{
unfree = hasUnfreeLicense attrs;
broken = isMarkedBroken attrs;
unsupported = hasUnsupportedPlatform attrs;
insecure = isMarkedInsecure attrs;
}
// (if hasDeniedUnfreeLicense attrs && !(hasWhitelistedLicense attrs) then
{ valid = false; reason = "unfree"; errormsg = "has an unfree license (‘${showLicense attrs.meta.license}’)"; }
else if hasBlacklistedLicense attrs then
{ valid = false; reason = "blacklisted"; errormsg = "has a blacklisted license (‘${showLicense attrs.meta.license}’)"; }
else if !allowBroken && attrs.meta.broken or false then
{ valid = false; reason = "broken"; errormsg = "is marked as broken"; }
else if !allowUnsupportedSystem && hasUnsupportedPlatform attrs then
{ valid = false; reason = "unsupported"; errormsg = "is not supported on ‘${hostPlatform.system}’"; }
else if !(hasAllowedInsecure attrs) then
{ valid = false; reason = "insecure"; errormsg = "is marked as insecure"; }
else if checkOutputsToInstall attrs then
{ valid = false; reason = "broken-outputs"; errormsg = "has invalid meta.outputsToInstall"; }
else let res = checkMeta (attrs.meta or {}); in if res != [] then
{ valid = false; reason = "unknown-meta"; errormsg = "has an invalid meta attrset:${lib.concatMapStrings (x: "\n\t - " + x) res}"; }
else { valid = true; });
assertValidity = { meta, attrs }: let
validity = checkValidity attrs;
in validity // {
# Throw an error if trying to evaluate an non-valid derivation
handled = if !validity.valid
then handleEvalIssue { inherit meta attrs; } { inherit (validity) reason errormsg; }
else true;
};
in assertValidity
