| | | 1 | | using AsiBackbone.Core.Signing; |
| | | 2 | | |
| | | 3 | | namespace AsiBackbone.Core.CapabilityTokens; |
| | | 4 | | |
| | | 5 | | public static class CapabilityGrantValidator |
| | | 6 | | { |
| | | 7 | | public static async ValueTask<CapabilityGrantValidationResult> ValidateAsync( |
| | | 8 | | SignedGovernanceArtifact<CapabilityTokenGrant> signedGrant, |
| | | 9 | | CapabilityGrantValidationOptions? options = null, |
| | | 10 | | IAsiBackboneSignatureVerificationService? verificationService = null, |
| | | 11 | | ICapabilityGrantUseStore? useStore = null, |
| | | 12 | | CancellationToken cancellationToken = default) |
| | | 13 | | { |
| | 104 | 14 | | ArgumentNullException.ThrowIfNull(signedGrant); |
| | 102 | 15 | | cancellationToken.ThrowIfCancellationRequested(); |
| | | 16 | | |
| | 100 | 17 | | CapabilityGrantValidationOptions effectiveOptions = options ?? CapabilityGrantValidationOptions.Create(); |
| | 100 | 18 | | CapabilityTokenGrant grant = signedGrant.Artifact; |
| | 100 | 19 | | DateTimeOffset validationUtc = (effectiveOptions.ValidationUtc ?? DateTimeOffset.UtcNow).ToUniversalTime(); |
| | | 20 | | |
| | 100 | 21 | | if (effectiveOptions.RequireProof) |
| | | 22 | | { |
| | 32 | 23 | | CapabilityGrantValidationResult? proofResult = await ValidateProofAsync( |
| | 32 | 24 | | signedGrant, |
| | 32 | 25 | | grant, |
| | 32 | 26 | | effectiveOptions, |
| | 32 | 27 | | verificationService, |
| | 32 | 28 | | cancellationToken).ConfigureAwait(false); |
| | | 29 | | |
| | 32 | 30 | | if (proofResult is not null) |
| | | 31 | | { |
| | 26 | 32 | | return proofResult; |
| | | 33 | | } |
| | | 34 | | } |
| | | 35 | | |
| | 74 | 36 | | CapabilityGrantValidationResult? metadataResult = ValidateMetadata(grant, effectiveOptions, validationUtc); |
| | | 37 | | |
| | 74 | 38 | | if (metadataResult is not null) |
| | | 39 | | { |
| | 36 | 40 | | return metadataResult; |
| | | 41 | | } |
| | | 42 | | |
| | 38 | 43 | | if (effectiveOptions.RequireUseCheck) |
| | | 44 | | { |
| | 24 | 45 | | CapabilityGrantValidationResult? useResult = await ValidateUseAsync( |
| | 24 | 46 | | grant, |
| | 24 | 47 | | effectiveOptions, |
| | 24 | 48 | | useStore, |
| | 24 | 49 | | validationUtc, |
| | 24 | 50 | | cancellationToken).ConfigureAwait(false); |
| | | 51 | | |
| | 24 | 52 | | if (useResult is not null) |
| | | 53 | | { |
| | 18 | 54 | | return useResult; |
| | | 55 | | } |
| | | 56 | | } |
| | | 57 | | |
| | 20 | 58 | | return CapabilityGrantValidationResult.Valid(grant); |
| | 100 | 59 | | } |
| | | 60 | | |
| | | 61 | | private static async ValueTask<CapabilityGrantValidationResult?> ValidateProofAsync( |
| | | 62 | | SignedGovernanceArtifact<CapabilityTokenGrant> signedGrant, |
| | | 63 | | CapabilityTokenGrant grant, |
| | | 64 | | CapabilityGrantValidationOptions options, |
| | | 65 | | IAsiBackboneSignatureVerificationService? verificationService, |
| | | 66 | | CancellationToken cancellationToken) |
| | | 67 | | { |
| | 32 | 68 | | if (verificationService is null) |
| | | 69 | | { |
| | 4 | 70 | | return CapabilityGrantValidationResult.Failed( |
| | 4 | 71 | | grant, |
| | 4 | 72 | | CapabilityTokenValidationCategory.MissingProof, |
| | 4 | 73 | | VerificationPolicyAction.Deny, |
| | 4 | 74 | | "capability.proof-verifier-missing", |
| | 4 | 75 | | "A proof verifier is required for this validation context."); |
| | | 76 | | } |
| | | 77 | | |
| | 28 | 78 | | var verificationContext = VerificationPolicyContext.Create( |
| | 28 | 79 | | purpose: CanonicalArtifactTypes.CapabilityTokenGrant, |
| | 28 | 80 | | expectedKeyId: options.ExpectedProofKeyId, |
| | 28 | 81 | | expectedKeyVersion: options.ExpectedProofKeyVersion, |
| | 28 | 82 | | expectedPolicyVersion: options.ExpectedProofPolicyVersion, |
| | 28 | 83 | | expectedPolicyHash: options.ExpectedProofPolicyHash, |
| | 28 | 84 | | requiredProvider: options.RequiredProofProvider, |
| | 28 | 85 | | requiredHashAlgorithm: options.RequiredProofHashAlgorithm); |
| | | 86 | | |
| | 28 | 87 | | VerificationPolicyOutcome verificationOutcome = await GovernanceArtifactVerifier.VerifyAsync( |
| | 28 | 88 | | signedGrant, |
| | 28 | 89 | | verificationService, |
| | 28 | 90 | | context: verificationContext, |
| | 28 | 91 | | cancellationToken: cancellationToken).ConfigureAwait(false); |
| | | 92 | | |
| | 28 | 93 | | return verificationOutcome.ShouldAllow |
| | 28 | 94 | | ? null |
| | 28 | 95 | | : CapabilityGrantValidationResult.Failed( |
| | 28 | 96 | | grant, |
| | 28 | 97 | | MapVerificationCategory(verificationOutcome.Category), |
| | 28 | 98 | | verificationOutcome.Action, |
| | 28 | 99 | | verificationOutcome.FailureCode ?? "capability.proof-invalid", |
| | 28 | 100 | | verificationOutcome.FailureMessage); |
| | 32 | 101 | | } |
| | | 102 | | |
| | | 103 | | private static CapabilityGrantValidationResult? ValidateMetadata( |
| | | 104 | | CapabilityTokenGrant grant, |
| | | 105 | | CapabilityGrantValidationOptions options, |
| | | 106 | | DateTimeOffset validationUtc) |
| | | 107 | | { |
| | 74 | 108 | | return options.Issuer is not null && !string.Equals(options.Issuer, grant.Issuer, StringComparison.Ordinal) |
| | 74 | 109 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.WrongIssuer, VerificationP |
| | 74 | 110 | | : options.Audience is not null && !string.Equals(options.Audience, grant.Audience, StringComparison.Ordinal) |
| | 74 | 111 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.WrongAudience, Verificatio |
| | 74 | 112 | | : IsNotYetValid(grant, validationUtc, options.AllowedClockSkew) |
| | 74 | 113 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.NotYetValid, VerificationP |
| | 74 | 114 | | : IsExpired(grant, validationUtc, options.AllowedClockSkew) |
| | 74 | 115 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.Expired, VerificationPolic |
| | 74 | 116 | | : options.Scopes.Count > 0 && !ContainsRequiredScopes(grant.Scopes, options.Scopes) |
| | 74 | 117 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.WrongScope, VerificationPo |
| | 74 | 118 | | : (options.PolicyVersion is not null && !string.Equals(options.PolicyVersion, grant.PolicyVersion, StringCom |
| | 74 | 119 | | || (options.PolicyHash is not null && !string.Equals(options.PolicyHash, grant.PolicyHash, StringComparison. |
| | 74 | 120 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.PolicyMismatch, Verificati |
| | 74 | 121 | | : options.RequireAcknowledgmentReference && !grant.HasAcknowledgmentReference |
| | 74 | 122 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.MissingAcknowledgmentRefer |
| | 74 | 123 | | : options.AcknowledgmentId is not null && !string.Equals(options.AcknowledgmentId, grant.AcknowledgmentId, S |
| | 74 | 124 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.AcknowledgmentMismatch, Ve |
| | 74 | 125 | | : options.HandshakeId is not null && !string.Equals(options.HandshakeId, grant.HandshakeId, StringComparison |
| | 74 | 126 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.HandshakeMismatch, Verific |
| | 74 | 127 | | : options.GatewayBinding is not null && !string.Equals(options.GatewayBinding, grant.GatewayBinding, StringC |
| | 74 | 128 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.GatewayMismatch, Verificat |
| | 74 | 129 | | : options.ResourceBinding is not null && !string.Equals(options.ResourceBinding, grant.ResourceBinding, Stri |
| | 74 | 130 | | ? CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.ResourceMismatch, Verifica |
| | 74 | 131 | | : null; |
| | | 132 | | } |
| | | 133 | | |
| | | 134 | | private static bool IsNotYetValid(CapabilityTokenGrant grant, DateTimeOffset validationUtc, TimeSpan allowedClockSke |
| | | 135 | | { |
| | 70 | 136 | | return grant.NotBeforeUtc.HasValue |
| | 70 | 137 | | && grant.NotBeforeUtc.Value > validationUtc |
| | 70 | 138 | | && grant.NotBeforeUtc.Value - validationUtc > allowedClockSkew; |
| | | 139 | | } |
| | | 140 | | |
| | | 141 | | private static bool IsExpired(CapabilityTokenGrant grant, DateTimeOffset validationUtc, TimeSpan allowedClockSkew) |
| | | 142 | | { |
| | 64 | 143 | | return validationUtc >= grant.ExpiresUtc |
| | 64 | 144 | | && validationUtc - grant.ExpiresUtc >= allowedClockSkew; |
| | | 145 | | } |
| | | 146 | | |
| | | 147 | | private static async ValueTask<CapabilityGrantValidationResult?> ValidateUseAsync( |
| | | 148 | | CapabilityTokenGrant grant, |
| | | 149 | | CapabilityGrantValidationOptions options, |
| | | 150 | | ICapabilityGrantUseStore? useStore, |
| | | 151 | | DateTimeOffset validationUtc, |
| | | 152 | | CancellationToken cancellationToken) |
| | | 153 | | { |
| | 24 | 154 | | if (useStore is null) |
| | | 155 | | { |
| | 4 | 156 | | return CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.ReplayStoreUnavailabl |
| | | 157 | | } |
| | | 158 | | |
| | 20 | 159 | | CapabilityGrantUseResult result = await useStore |
| | 20 | 160 | | .TryConsumeAsync(grant, options.MaxUseCount, validationUtc, cancellationToken) |
| | 20 | 161 | | .ConfigureAwait(false); |
| | | 162 | | |
| | 20 | 163 | | return result.State switch |
| | 20 | 164 | | { |
| | 6 | 165 | | GrantUseState.Accepted => null, |
| | 4 | 166 | | GrantUseState.UseLimitExceeded => CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCat |
| | 2 | 167 | | GrantUseState.Stopped => CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.Rev |
| | 2 | 168 | | GrantUseState.Cancelled => CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.C |
| | 4 | 169 | | GrantUseState.Unavailable => CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory |
| | 2 | 170 | | _ => CapabilityGrantValidationResult.Failed(grant, CapabilityTokenValidationCategory.Failed, VerificationPol |
| | 20 | 171 | | }; |
| | 24 | 172 | | } |
| | | 173 | | |
| | | 174 | | private static bool ContainsRequiredScopes(IReadOnlyList<string> actualScopes, IReadOnlyList<string> requiredScopes) |
| | | 175 | | { |
| | 50 | 176 | | HashSet<string> actualScopeSet = new(actualScopes, StringComparer.Ordinal); |
| | | 177 | | |
| | 200 | 178 | | foreach (string requiredScope in requiredScopes) |
| | | 179 | | { |
| | 52 | 180 | | if (!actualScopeSet.Contains(requiredScope)) |
| | | 181 | | { |
| | 4 | 182 | | return false; |
| | | 183 | | } |
| | | 184 | | } |
| | | 185 | | |
| | 46 | 186 | | return true; |
| | 4 | 187 | | } |
| | | 188 | | |
| | | 189 | | private static CapabilityTokenValidationCategory MapVerificationCategory(SignatureVerificationCategory category) |
| | | 190 | | { |
| | 22 | 191 | | return category switch |
| | 22 | 192 | | { |
| | 2 | 193 | | SignatureVerificationCategory.MissingSignature => CapabilityTokenValidationCategory.MissingProof, |
| | 0 | 194 | | SignatureVerificationCategory.Valid => CapabilityTokenValidationCategory.Valid, |
| | 2 | 195 | | SignatureVerificationCategory.InvalidSignature => CapabilityTokenValidationCategory.InvalidProof, |
| | 2 | 196 | | SignatureVerificationCategory.HashMismatch => CapabilityTokenValidationCategory.InvalidProof, |
| | 2 | 197 | | SignatureVerificationCategory.RevokedKey => CapabilityTokenValidationCategory.Revoked, |
| | 4 | 198 | | SignatureVerificationCategory.ProviderUnavailable => CapabilityTokenValidationCategory.Failed, |
| | 4 | 199 | | SignatureVerificationCategory.UnknownKeyVersion => CapabilityTokenValidationCategory.Failed, |
| | 2 | 200 | | SignatureVerificationCategory.CanonicalizationMismatch => CapabilityTokenValidationCategory.Failed, |
| | 2 | 201 | | SignatureVerificationCategory.UnsupportedAlgorithm => CapabilityTokenValidationCategory.InvalidProof, |
| | 2 | 202 | | SignatureVerificationCategory.Failed => CapabilityTokenValidationCategory.Failed, |
| | 0 | 203 | | _ => CapabilityTokenValidationCategory.Failed |
| | 22 | 204 | | }; |
| | | 205 | | } |
| | | 206 | | } |