Add methods for checking an identity satisfies a statement

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/identityobject/IdentityObject.java

@@ -1,6 +1,9 @@
 package com.concordium.sdk.crypto.wallet.identityobject;
 
+import com.concordium.sdk.responses.accountinfo.credential.AttributeType;
+
 import lombok.Getter;
+import lombok.val;
 
 @Getter
 public class IdentityObject {
@@ -9,4 +12,11 @@ public class IdentityObject {
     private PreIdentityObject preIdentityObject;
     private String signature;
 
+    public String getChosenAttribute(AttributeType attribute) throws MissingAttributeException {
+        val chosenAttributes = this.getAttributeList().getChosenAttributes();
+        if (!chosenAttributes.containsKey(attribute)) {
+            throw new MissingAttributeException(attribute);
+        }
+        return chosenAttributes.get(attribute);        
+    } 
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/identityobject/MissingAttributeException.java

@@ -0,0 +1,14 @@
+package com.concordium.sdk.crypto.wallet.identityobject;
+
+import com.concordium.sdk.responses.accountinfo.credential.AttributeType;
+
+import lombok.Getter;
+
+@Getter
+public class MissingAttributeException extends Exception {
+    private AttributeType attribute;
+
+    public MissingAttributeException(AttributeType attribute) {
+        this.attribute = attribute;
+    }
+}

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/CredentialAttribute.java

@@ -1,6 +1,8 @@
 package com.concordium.sdk.crypto.wallet.web3Id;
 
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.time.LocalDateTime;
 
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParseException;
@@ -21,8 +23,8 @@
 @JsonDeserialize(using = CredentialAttribute.CredentialAttributieTypeDeserializer.class)
 @Builder
 @Getter
-public class CredentialAttribute {
-    enum CredentialAttributeType {
+public final class CredentialAttribute {
+    public enum CredentialAttributeType {
         INT,
         STRING,
         TIMESTAMP;
@@ -31,8 +33,59 @@ enum CredentialAttributeType {
     private String value;
     private CredentialAttributeType type;
 
-    static class CredentialAttributieTypeDeserializer extends JsonDeserializer<CredentialAttribute> {
+    private int compareStringAttributes(byte[] aBytes, byte[] bBytes) {
+        if (aBytes.length < bBytes.length) return -1;
+        if (aBytes.length > bBytes.length) return 1;
+
+        for (int i = 0; i < aBytes.length; i++) {
+            byte aByte = aBytes[i];
+            byte bByte = bBytes[i];
+
+            if (aByte == bByte) continue;
+            return aByte < bByte ? -1 : 1;
+        }
+
+        return 0;
+    }
+
+    public boolean isBetween(CredentialAttribute lower, CredentialAttribute upper) throws IllegalArgumentException {
+        if (!this.getType().equals(lower.getType()) || !this.getType().equals(upper.getType())) {
+            throw new IllegalArgumentException("Attribute types must match");
+        }
+        switch (this.type) {
+            case INT: {
+                long lowerVal = Long.parseLong(lower.getValue());
+                long upperVal =  Long.parseLong(upper.getValue());
+                long val = Long.parseLong(this.getValue());
+                return lowerVal <= val && val < upperVal;
+            }
+            case TIMESTAMP: {
+                LocalDateTime lowerVal = LocalDateTime.parse(lower.getValue());
+                LocalDateTime upperVal = LocalDateTime.parse(upper.getValue());
+                LocalDateTime val = LocalDateTime.parse(this.getValue());
+                return !lowerVal.isAfter(val) && upperVal.isAfter(val);
+            }
+            case STRING: {
+                byte[] lowerVal = lower.getValue().getBytes(StandardCharsets.UTF_8);
+                byte[] upperVal = upper.getValue().getBytes(StandardCharsets.UTF_8);
+                byte[] val = this.getValue().getBytes(StandardCharsets.UTF_8);
+                return this.compareStringAttributes(val, lowerVal) >= 0 && this.compareStringAttributes(val, upperVal) < 0;
+            }
+            default:
+                throw new IllegalArgumentException("Unknown attribute type");
+        }
+    }
 
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof CredentialAttribute)) {
+            return false;
+        }
+        CredentialAttribute cred = (CredentialAttribute) obj;
+        return this.type.equals(cred.type) && this.value.equals(cred.value);
+    }
+
+    static class CredentialAttributieTypeDeserializer extends JsonDeserializer<CredentialAttribute> {
         @Override
         public CredentialAttribute deserialize(JsonParser p, DeserializationContext ctxt)
                 throws IOException, JsonProcessingException {

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/AtomicStatement.java

@@ -8,9 +8,24 @@
 
 import static com.fasterxml.jackson.annotation.JsonTypeInfo.Id.NAME;
 
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
+import com.concordium.sdk.crypto.wallet.web3Id.CredentialAttribute;
+import com.concordium.sdk.responses.accountinfo.credential.AttributeType;
+
 @JsonTypeInfo(use = NAME, include = As.PROPERTY, property = "type", visible = true)
 @JsonSubTypes ({@Type (value = RevealStatement.class), @Type (value = RangeStatement.class), @Type (value = MembershipStatement.class), @Type (value = NonMembershipStatement.class)})
 public abstract class AtomicStatement {
    @JsonProperty("attributeTag")
    public abstract String getAttributeTag();
+
+   // TODO: add overload for web3Id credential
+   protected CredentialAttribute getAttributeValue(IdentityObject identityObject) throws Exception {
+      AttributeType type = AttributeType.fromJSON(this.getAttributeTag());
+      String raw = identityObject.getAttributeList().getChosenAttributes().get(type);
+      return CredentialAttribute.builder().value(raw).type(CredentialAttribute.CredentialAttributeType.STRING).build();
+
+   }
+
+   // TODO: add overload for web3Id credential
+   public abstract boolean canBeProvedBy(IdentityObject identityObject) throws Exception;
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/MembershipStatement.java

@@ -2,6 +2,8 @@
 
 import java.util.List;
 
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
+import com.concordium.sdk.crypto.wallet.identityobject.MissingAttributeException;
 import com.concordium.sdk.crypto.wallet.web3Id.CredentialAttribute;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
@@ -12,4 +14,15 @@
 public class MembershipStatement extends AtomicStatement {
     private String attributeTag;
     private List<CredentialAttribute> set;
+
+    @Override
+    public boolean canBeProvedBy(IdentityObject identityObject) throws Exception {
+        try {
+            CredentialAttribute value = this.getAttributeValue(identityObject);
+            return set.contains(value);
+        } catch (MissingAttributeException e) {
+            // If the identityObject does not have the relevant attribute, it does not satisfy the statement 
+            return false;
+        }
+    }
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/NonMembershipStatement.java

@@ -2,6 +2,7 @@
 
 import java.util.List;
 
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
 import com.concordium.sdk.crypto.wallet.web3Id.CredentialAttribute;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
@@ -12,4 +13,14 @@
 public class NonMembershipStatement extends AtomicStatement {
     private String attributeTag;
     private List<CredentialAttribute> set;
+
+    @Override
+    public boolean canBeProvedBy(IdentityObject identityObject) {
+        try {
+            CredentialAttribute value = this.getAttributeValue(identityObject);
+            return !set.contains(value);
+        } catch (Exception e) {
+            return false;
+        }
+    }
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/RangeStatement.java

@@ -1,7 +1,8 @@
 package com.concordium.sdk.crypto.wallet.web3Id.Statement;
 
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
+import com.concordium.sdk.crypto.wallet.identityobject.MissingAttributeException;
 import com.concordium.sdk.crypto.wallet.web3Id.CredentialAttribute;
-import com.concordium.sdk.responses.accountinfo.credential.AttributeType;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
 import lombok.Builder;
@@ -16,4 +17,15 @@ public class RangeStatement extends AtomicStatement {
     private CredentialAttribute lower;
     private CredentialAttribute upper;
     private String attributeTag;
+    @Override
+    public boolean canBeProvedBy(IdentityObject identityObject) throws Exception {
+        try {
+            CredentialAttribute value = getAttributeValue(identityObject);
+            return value.isBetween(lower, upper);
+        } catch (MissingAttributeException e) {
+            // If the identityObject does not have the relevant attribute, it does not satisfy the statement 
+            return false;
+        }
+
+    }
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/RequestStatement.java

@@ -1,6 +1,9 @@
 package com.concordium.sdk.crypto.wallet.web3Id.Statement;
 
 import java.util.List;
+import java.util.stream.Collectors;
+
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
 
 import lombok.Builder;
 import lombok.Getter;
@@ -13,4 +16,22 @@ public class RequestStatement {
     private String id;
     private List<String> type;
     private List<AtomicStatement> statement;
+
+    public List<AtomicStatement> getUnsatisfiedStatements(IdentityObject identityObject) {
+        return statement.stream().filter(s -> {
+            try {
+                return !s.canBeProvedBy(identityObject);
+            } catch (Exception e) {
+                return false;
+            }
+        }).collect(Collectors.toList());
+    }
+
+    public boolean canBeProvedBy(IdentityObject identityObject) throws Exception {
+        for (AtomicStatement s: this.statement) {
+            if (s.canBeProvedBy(identityObject)) continue;
+            return false;
+        }
+        return true;        
+    }
 }

concordium-sdk/src/main/java/com/concordium/sdk/crypto/wallet/web3Id/Statement/RevealStatement.java

@@ -1,5 +1,7 @@
 package com.concordium.sdk.crypto.wallet.web3Id.Statement;
 
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
+import com.concordium.sdk.crypto.wallet.identityobject.MissingAttributeException;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
 import lombok.Getter;
@@ -8,4 +10,17 @@
 @JsonTypeName("RevealAttribute")
 public class RevealStatement extends AtomicStatement {
     private String attributeTag;
+
+    @Override
+    public boolean canBeProvedBy(IdentityObject identityObject) throws Exception {
+        try {
+            // Attempt to get the attribute
+            this.getAttributeValue(identityObject);
+        } catch (MissingAttributeException e) {
+            // If the identityObject does not have the relevant attribute, it does not satisfy the statement 
+            return false;
+        }
+        // With a reveal statement, the only requirement is that the identity has the attribute.
+        return true;
+    }
 }

concordium-sdk/src/main/java/com/concordium/sdk/responses/accountinfo/credential/AttributeType.java

@@ -1,5 +1,6 @@
 package com.concordium.sdk.responses.accountinfo.credential;
 
+import com.concordium.sdk.serializing.JsonMapper;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 /**
@@ -36,5 +37,9 @@ public enum AttributeType {
     @JsonProperty("taxIdNo")
     TAX_ID_NO,
     @JsonProperty("lei")
-    LEI
+    LEI;
+
+    public static AttributeType fromJSON(String jsonStr) throws Exception {
+        return JsonMapper.INSTANCE.readValue(String.format("\"%s\"", jsonStr), AttributeType.class);
+    }
 }

concordium-sdk/src/test/java/com/concordium/sdk/crypto/wallet/CredentialTest.java

@@ -32,36 +32,6 @@
 
 public class CredentialTest {
 
-    static String readFile(String path, Charset encoding)
-            throws IOException {
-        byte[] encoded = Files.readAllBytes(Paths.get(path));
-        return new String(encoded, encoding);
-    }
-
-    private CryptographicParameters getCryptographicParameters() throws Exception {
-        return JsonMapper.INSTANCE.readValue(
-                readFile("./src/test/testresources/wallet/global.json", Charset.forName("UTF-8")),
-                CryptographicParameters.class);
-    }
-
-    private IdentityProviderInfo getIdentityProviderInfo() throws Exception {
-        return JsonMapper.INSTANCE.readValue(
-                readFile("./src/test/testresources/wallet/ip_info.json", Charset.forName("UTF-8")),
-                IdentityProviderInfo.class);
-    }
-
-    private Map<String, AnonymityRevokerInfo> getAnonymityRevokerInfos() throws Exception {
-        MapType mapType = TypeFactory.defaultInstance().constructMapType(Map.class, String.class,
-                AnonymityRevokerInfo.class);
-        return JsonMapper.INSTANCE.readValue(
-                readFile("./src/test/testresources/wallet/ars_infos.json", Charset.forName("UTF-8")), mapType);
-    }
-
-    private IdentityObject getIdentityObject() throws Exception {
-    return JsonMapper.INSTANCE.readValue(
-                readFile("./src/test/testresources/wallet/id_object.json", Charset.forName("UTF-8")),
-                IdentityObject.class);    }
-
     private static String TEST_SEED = "efa5e27326f8fa0902e647b52449bf335b7b605adc387015ec903f41d95080eb71361cbc7fb78721dcd4f3926a337340aa1406df83332c44c1cdcfe100603860";
 
     @Test
@@ -76,10 +46,10 @@ public void createUnsignedCredential() throws Exception {
         }
 
         UnsignedCredentialInput input = UnsignedCredentialInput.builder()
-            .ipInfo(getIdentityProviderInfo())
-            .globalContext(getCryptographicParameters())
-            .arsInfos(getAnonymityRevokerInfos())
-            .idObject(getIdentityObject())
+            .ipInfo(FileHelpers.getIdentityProviderInfo())
+            .globalContext(FileHelpers.getCryptographicParameters())
+            .arsInfos(FileHelpers.getAnonymityRevokerInfos())
+            .idObject(FileHelpers.getIdentityObject())
             .credNumber(credentialCounter)
             .attributeRandomness(attributeRandomness)
             .blindingRandomness(wallet.getSignatureBlindingRandomness(0, 0))

concordium-sdk/src/test/java/com/concordium/sdk/crypto/wallet/FileHelpers.java

@@ -0,0 +1,48 @@
+package com.concordium.sdk.crypto.wallet;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Map;
+
+import com.concordium.sdk.crypto.wallet.identityobject.IdentityObject;
+import com.concordium.sdk.responses.blocksummary.updates.queues.AnonymityRevokerInfo;
+import com.concordium.sdk.responses.blocksummary.updates.queues.IdentityProviderInfo;
+import com.concordium.sdk.responses.cryptographicparameters.CryptographicParameters;
+import com.concordium.sdk.serializing.JsonMapper;
+import com.fasterxml.jackson.databind.type.MapType;
+import com.fasterxml.jackson.databind.type.TypeFactory;
+
+public class FileHelpers {
+    public static String readFile(String path, Charset encoding)
+            throws IOException {
+        byte[] encoded = Files.readAllBytes(Paths.get(path));
+        return new String(encoded, encoding);
+    }
+
+    public static CryptographicParameters getCryptographicParameters() throws Exception {
+        return JsonMapper.INSTANCE.readValue(
+                readFile("./src/test/testresources/wallet/global.json", Charset.forName("UTF-8")),
+                CryptographicParameters.class);
+    }
+
+    public static IdentityProviderInfo getIdentityProviderInfo() throws Exception {
+        return JsonMapper.INSTANCE.readValue(
+                readFile("./src/test/testresources/wallet/ip_info.json", Charset.forName("UTF-8")),
+                IdentityProviderInfo.class);
+    }
+
+    public static Map<String, AnonymityRevokerInfo> getAnonymityRevokerInfos() throws Exception {
+        MapType mapType = TypeFactory.defaultInstance().constructMapType(Map.class, String.class,
+                AnonymityRevokerInfo.class);
+        return JsonMapper.INSTANCE.readValue(
+                readFile("./src/test/testresources/wallet/ars_infos.json", Charset.forName("UTF-8")), mapType);
+    }
+
+    public static IdentityObject getIdentityObject() throws Exception {
+    return JsonMapper.INSTANCE.readValue(
+                readFile("./src/test/testresources/wallet/id_object.json", Charset.forName("UTF-8")),
+                IdentityObject.class);    }
+
+}