Add AuthzClientCryptoProvider for authorization client cryptographic operations

authz/client/pom.xml

@@ -58,6 +58,17 @@
             <artifactId>jackson-annotations</artifactId>
             <scope>provided</scope>
         </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

authz/client/src/main/java/org/keycloak/authorization/client/AuthzClient.java

@@ -30,6 +30,7 @@
 import org.keycloak.authorization.client.resource.ProtectionResource;
 import org.keycloak.authorization.client.util.Http;
 import org.keycloak.authorization.client.util.TokenCallable;
+import org.keycloak.common.crypto.CryptoIntegration;
 import org.keycloak.common.util.KeycloakUriBuilder;
 import org.keycloak.representations.AccessTokenResponse;
 import org.keycloak.util.SystemPropertiesJsonParserFactory;
@@ -91,6 +92,7 @@ public static AuthzClient create(InputStream configStream) throws RuntimeExcepti
      * @return a new instance
      */
     public static AuthzClient create(Configuration configuration) {
+        CryptoIntegration.init(AuthzClient.class.getClassLoader());
         return new AuthzClient(configuration);
     }
 

authz/client/src/main/java/org/keycloak/authorization/client/util/crypto/ASN1Decoder.java

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2024 Red Hat, Inc. and/or its affiliates
+ *  and other contributors as indicated by the @author tags.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+package org.keycloak.authorization.client.util.crypto;
+
+import java.io.ByteArrayInputStream;
+import java.io.EOFException;
+import java.io.IOException;
+import java.math.BigInteger;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ *
+ * @author rmartinc
+ */
+class ASN1Decoder {
+
+    private final ByteArrayInputStream is;
+    private final int limit;
+    private int count;
+
+    ASN1Decoder(byte[] bytes) {
+        is = new ByteArrayInputStream(bytes);
+        count = 0;
+        limit = bytes.length;
+    }
+
+    public static ASN1Decoder create(byte[] bytes) {
+        return new ASN1Decoder(bytes);
+    }
+
+    public List<byte[]> readSequence() throws IOException {
+        int tag = readTag();
+        int tagNo = readTagNumber(tag);
+        if (tagNo != ASN1Encoder.SEQUENCE) {
+            throw new IOException("Invalid Sequence tag " + tagNo);
+        }
+        int length = readLength();
+        List<byte[]> result = new ArrayList<>();
+        while (length > 0) {
+            byte[] bytes = readNext();
+            result.add(bytes);
+            length = length - bytes.length;
+        }
+        return result;
+    }
+
+    public BigInteger readInteger() throws IOException {
+        int tag = readTag();
+        int tagNo = readTagNumber(tag);
+        if (tagNo != ASN1Encoder.INTEGER) {
+            throw new IOException("Invalid Integer tag " + tagNo);
+        }
+        int length = readLength();
+        byte[] bytes = read(length);
+        return new BigInteger(bytes);
+    }
+
+    byte[] readNext() throws IOException {
+        mark();
+        int tag = readTag();
+        readTagNumber(tag);
+        int length = readLength();
+        length += reset();
+        return read(length);
+    }
+
+    int readTag() throws IOException {
+        int tag = read();
+        if (tag < 0) {
+            throw new EOFException("EOF found inside tag value.");
+        }
+        return tag;
+    }
+
+    int readTagNumber(int tag) throws IOException {
+        int tagNo = tag & 0x1f;
+
+        //
+        // with tagged object tag number is bottom 5 bits, or stored at the start of the content
+        //
+        if (tagNo == 0x1f) {
+            tagNo = 0;
+
+            int b = read();
+
+            // X.690-0207 8.1.2.4.2
+            // "c) bits 7 to 1 of the first subsequent octet shall not all be zero."
+            if ((b & 0x7f) == 0) // Note: -1 will pass
+            {
+                throw new IOException("corrupted stream - invalid high tag number found");
+            }
+
+            while ((b >= 0) && ((b & 0x80) != 0)) {
+                tagNo |= (b & 0x7f);
+                tagNo <<= 7;
+                b = read();
+            }
+
+            if (b < 0) {
+                throw new EOFException("EOF found inside tag value.");
+            }
+
+            tagNo |= (b & 0x7f);
+        }
+
+        return tagNo;
+    }
+
+    int readLength() throws IOException {
+        int length = read();
+        if (length < 0) {
+            throw new EOFException("EOF found when length expected");
+        }
+
+        if (length == 0x80) {
+            return -1;      // indefinite-length encoding
+        }
+
+        if (length > 127) {
+            int size = length & 0x7f;
+
+            // Note: The invalid long form "0xff" (see X.690 8.1.3.5c) will be caught here
+            if (size > 4) {
+                throw new IOException("DER length more than 4 bytes: " + size);
+            }
+
+            length = 0;
+            for (int i = 0; i < size; i++) {
+                int next = read();
+
+                if (next < 0) {
+                    throw new EOFException("EOF found reading length");
+                }
+
+                length = (length << 8) + next;
+            }
+
+            if (length < 0) {
+                throw new IOException("corrupted stream - negative length found");
+            }
+
+            if (length >= limit) // after all we must have read at least 1 byte
+            {
+                throw new IOException("corrupted stream - out of bounds length found");
+            }
+        }
+
+        return length;
+    }
+
+    byte[] read(int length) throws IOException {
+        byte[] bytes = new byte[length];
+        int totalBytesRead = 0;
+
+        while (totalBytesRead < length) {
+            int bytesRead = is.read(bytes, totalBytesRead, length - totalBytesRead);
+            if (bytesRead == -1) {
+                throw new IOException(String.format("EOF found reading %d bytes", length));
+            }
+            totalBytesRead += bytesRead;
+        }
+        count += length;
+        return bytes;
+    }
+
+    void mark() {
+        count = 0;
+        is.mark(is.available());
+    }
+
+    int reset() {
+        int tmp = count;
+        is.reset();
+        return tmp;
+    }
+
+    int read() {
+        int tmp = is.read();
+        if (tmp >= 0) {
+            count++;
+        }
+        return tmp;
+    }
+}
+

authz/client/src/main/java/org/keycloak/authorization/client/util/crypto/ASN1Encoder.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2024 Red Hat, Inc. and/or its affiliates
+ *  and other contributors as indicated by the @author tags.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+package org.keycloak.authorization.client.util.crypto;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.math.BigInteger;
+
+/**
+ *
+ * @author rmartinc
+ */
+class ASN1Encoder {
+
+    static final int INTEGER = 0x02;
+    static final int SEQUENCE = 0x10;
+    static final int CONSTRUCTED = 0x20;
+
+    private final ByteArrayOutputStream os;
+
+    private ASN1Encoder() {
+        this.os = new ByteArrayOutputStream();
+    }
+
+    static public ASN1Encoder create() {
+        return new ASN1Encoder();
+    }
+
+    public ASN1Encoder write(BigInteger value) throws IOException {
+        writeEncoded(INTEGER, value.toByteArray());
+        return this;
+    }
+
+    public ASN1Encoder writeDerSeq(ASN1Encoder... objects) throws IOException {
+        writeEncoded(CONSTRUCTED | SEQUENCE, concatenate(objects));
+        return this;
+    }
+
+    public byte[] toByteArray() {
+        return os.toByteArray();
+    }
+
+    void writeEncoded(int tag, byte[] bytes) throws IOException {
+        write(tag);
+        writeLength(bytes.length);
+        write(bytes);
+    }
+
+    void writeLength(int length) throws IOException {
+        if (length > 127) {
+            int size = 1;
+            int val = length;
+
+            while ((val >>>= 8) != 0) {
+                size++;
+            }
+
+            write((byte) (size | 0x80));
+
+            for (int i = (size - 1) * 8; i >= 0; i -= 8) {
+                write((byte) (length >> i));
+            }
+        } else {
+            write((byte) length);
+        }
+    }
+
+    void write(byte[] bytes) throws IOException {
+        os.write(bytes);
+    }
+
+    void write(int b) throws IOException {
+        os.write(b);
+    }
+
+    byte[] concatenate(ASN1Encoder... objects) throws IOException {
+        ByteArrayOutputStream tmp = new ByteArrayOutputStream();
+        for (ASN1Encoder object : objects) {
+            tmp.write(object.toByteArray());
+        }
+        return tmp.toByteArray();
+    }
+}
+