Added EmbeddedSignatureBlob component method

Author: AlexanderOMara

Security/CodeSigning/sigblob.test.ts

@@ -1,5 +1,5 @@
 import { assertEquals, assertInstanceOf } from '@std/assert';
-import { PLBoolean, PLDictionary } from '@hqtsm/plist';
+import { PLBoolean, PLData, PLDictionary } from '@hqtsm/plist';
 import { assertThrowsMacOSError } from '../../spec/assert.ts';
 import {
 	CPU_ARCHITECTURES,
@@ -171,6 +171,38 @@ Deno.test('EmbeddedSignatureBlob: blobData', () => {
 	}, errSecCSSignatureInvalid);
 });
 
+Deno.test('EmbeddedSignatureBlob: component', () => {
+	{
+		const maker = new EmbeddedSignatureBlob_Maker();
+		const made = EmbeddedSignatureBlob_Maker.make(maker);
+		const component = EmbeddedSignatureBlob.component(
+			made,
+			cdSignatureSlot,
+		);
+		assertEquals(component, null);
+	}
+	{
+		const maker = new EmbeddedSignatureBlob_Maker();
+		const filler = new ArrayBuffer(16);
+		for (let a = new Uint8Array(filler), i = filler.byteLength; i--;) {
+			a[i] = i;
+		}
+		const blob = new BlobCore(filler);
+		BlobCore.initialize(blob, cdRequirementsSlot, filler.byteLength);
+		EmbeddedSignatureBlob_Maker.add(maker, cdRequirementsSlot, blob);
+		const made = EmbeddedSignatureBlob_Maker.make(maker);
+		const component = EmbeddedSignatureBlob.component(
+			made,
+			cdRequirementsSlot,
+		);
+		assertInstanceOf(component, PLData);
+		assertEquals(
+			new Uint8Array(component.buffer),
+			new Uint8Array(filler),
+		);
+	}
+});
+
 Deno.test('EmbeddedSignatureBlob: fixtures', async () => {
 	const signedFictures = fixtures.filter((f) =>
 		[...f.archs.values()].filter(Boolean).length

Security/CodeSigning/sigblob.ts

@@ -59,6 +59,24 @@ export class EmbeddedSignatureBlob<
 		MacOSError.throwMe(errSecCSSignatureInvalid);
 	}
 
+	/**
+	 * Find blob data for slot.
+	 *
+	 * @param _this This.
+	 * @param slot Slot.
+	 * @returns Blob data or null.
+	 */
+	public static component(
+		_this: EmbeddedSignatureBlob,
+		slot: CodeDirectory_SpecialSlot,
+	): PLData | null {
+		const blob = EmbeddedSignatureBlob.find(_this, slot);
+		if (blob) {
+			return EmbeddedSignatureBlob.blobData(slot, blob);
+		}
+		return null;
+	}
+
 	static {
 		toStringTag(this, 'EmbeddedSignatureBlob');
 		constant(this, 'typeMagic');