From d342a45d98c4795b3a3fe1aaef5236ad4a782b55 Mon Sep 17 00:00:00 2001
From: Yuuta Liang <yuutaw@students.cs.ubc.ca>
Date: Thu, 12 Oct 2023 12:10:33 +0800
Subject: Implement data structures from X.680, X.501, X.509, and PKCS#10, with
 X.690 encoding / decoding support

The implementation took four days, and it is still a little bit rough. Updated version should arrive soon.

Signed-off-by: Yuuta Liang <yuutaw@students.cs.ubc.ca>
---
 src/main/model/pki/SubjectPublicKeyInfo.java | 83 ++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 src/main/model/pki/SubjectPublicKeyInfo.java

(limited to 'src/main/model/pki/SubjectPublicKeyInfo.java')

diff --git a/src/main/model/pki/SubjectPublicKeyInfo.java b/src/main/model/pki/SubjectPublicKeyInfo.java
new file mode 100644
index 0000000..ac72055
--- /dev/null
+++ b/src/main/model/pki/SubjectPublicKeyInfo.java
@@ -0,0 +1,83 @@
+package model.pki;
+
+import model.asn1.ASN1Object;
+import model.asn1.BitString;
+import model.asn1.Tag;
+import model.asn1.exceptions.ParseException;
+import model.asn1.parsing.BytesReader;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.stream.Stream;
+
+/**
+ * Represents the following ASN.1 structure:
+ * <pre>
+ *     SubjectPublicKeyInfo ::= SEQUENCE {
+ *          algorithm AlgorithmIdentifier{{SupportedAlgorithms}},
+ *          subjectPublicKey BIT STRING,
+ *     ... }
+ * </pre>
+ * It represents the public key of a subject, in a certificate.
+ */
+public class SubjectPublicKeyInfo extends ASN1Object {
+    /**
+     * The algorithm used.
+     */
+    private final AlgorithmIdentifier algorithm;
+
+    /**
+     * The public key.
+     */
+    private final BitString subjectPublicKey;
+
+    /**
+     * EFFECTS: Init with tags, algorithm, subjectPublicKey. For tags, see {@link ASN1Object}.
+     * REQUIRES: The public key should be a valid $algorithm key. Algorithm and publicKey should have default UNIVERSAL
+     * tags (SEQUENCE and BIT STRING).
+     */
+    public SubjectPublicKeyInfo(Tag tag, Tag parentTag,
+                                final AlgorithmIdentifier algorithm,
+                                final BitString subjectPublicKey) {
+        super(tag, parentTag);
+        this.algorithm = algorithm;
+        this.subjectPublicKey = subjectPublicKey;
+    }
+
+    /**
+     * EFFECTS: Parse input DER.
+     *   Throws {@link ASN1Object} if invalid:
+     *    - Any fields missing (info, algorithm, signature)
+     *    - Any fields having an incorrect tag (as seen in the ASN.1 definition)
+     *    - Any fields with encoding instructions that violate implicit / explicit encoding rules
+     *    - Other issues found during parsing the object, like early EOF (see {@link ASN1Object})
+     * MODIFIES: this, encoded
+     */
+    public SubjectPublicKeyInfo(BytesReader encoded, boolean hasParentTag) throws ParseException {
+        super(encoded, hasParentTag);
+        this.algorithm = new AlgorithmIdentifier(encoded, false);
+        this.algorithm.getTag().enforce(TAG_SEQUENCE);
+
+        this.subjectPublicKey = new BitString(encoded, false);
+        this.subjectPublicKey.getTag().enforce(BitString.TAG);
+    }
+
+    /**
+     * EFFECTS: Encode the fields into DER, in the order.
+     */
+    @Override
+    public Byte[] encodeValueDER() {
+        return Stream.of(Arrays.asList(algorithm.encodeDER()),
+                        Arrays.asList(subjectPublicKey.encodeDER()))
+                .flatMap(Collection::stream)
+                .toArray(Byte[]::new);
+    }
+
+    public AlgorithmIdentifier getAlgorithm() {
+        return algorithm;
+    }
+
+    public BitString getSubjectPublicKey() {
+        return subjectPublicKey;
+    }
+}
-- 
cgit v1.2.3