PemParser Class — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/ssl/pem/PemPrivateKeyParser.java lines 226–274

	private static class PemParser {

		private final Pattern pattern;

		private final BiFunction<byte[], @Nullable String, PKCS8EncodedKeySpec> keySpecFactory;

		private final String[] algorithms;

		PemParser(String header, String footer,
				BiFunction<byte[], @Nullable String, PKCS8EncodedKeySpec> keySpecFactory, String... algorithms) {
			this.pattern = Pattern.compile(header + BASE64_TEXT + footer, Pattern.CASE_INSENSITIVE);
			this.keySpecFactory = keySpecFactory;
			this.algorithms = algorithms;
		}

		@Nullable PrivateKey parse(String text, @Nullable String password) {
			Matcher matcher = this.pattern.matcher(text);
			return (!matcher.find()) ? null : parse(decodeBase64(matcher.group(BASE64_TEXT_GROUP)), password);
		}

		private static byte[] decodeBase64(String content) {
			byte[] contentBytes = content.replaceAll("\r", "").replaceAll("\n", "").getBytes();
			return Base64.getDecoder().decode(contentBytes);
		}

		private @Nullable PrivateKey parse(byte[] bytes, @Nullable String password) {
			PKCS8EncodedKeySpec keySpec = this.keySpecFactory.apply(bytes, password);
			if (keySpec.getAlgorithm() != null) {
				try {
					KeyFactory keyFactory = KeyFactory.getInstance(keySpec.getAlgorithm());
					return keyFactory.generatePrivate(keySpec);
				}
				catch (InvalidKeySpecException | NoSuchAlgorithmException ex) {
					// Ignore
				}
			}
			for (String algorithm : this.algorithms) {
				try {
					KeyFactory keyFactory = KeyFactory.getInstance(algorithm);
					return keyFactory.generatePrivate(keySpec);
				}
				catch (InvalidKeySpecException | NoSuchAlgorithmException ex) {
					// Ignore
				}
			}
			return null;
		}

	}