1 /*
2 * Copyright (c) 2000-2021 The Legion of the Bouncy Castle Inc. (https://www.bouncycastle.org)
3 * <p>
4 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
5 * and associated documentation files (the "Software"), to deal in the Software without restriction,
6 *including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
7 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
8 * subject to the following conditions:
9 * </p>
10 * <p>
11 * The above copyright notice and this permission notice shall be included in all copies or substantial
12 * portions of the Software.
13 * </p>
14 * <p>
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
16 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
17 * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
18 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
19 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 * </p>
22 */
23 package org.eclipse.jgit.gpg.bc.internal.keys;
24
25 // This class is an unmodified copy from Bouncy Castle; needed because it's package-visible only and used by SExprParser.
26
27 import java.io.IOException;
28 import java.io.InputStream;
29
30 import org.bouncycastle.bcpg.HashAlgorithmTags;
31 import org.bouncycastle.bcpg.S2K;
32 import org.bouncycastle.util.io.Streams;
33
34 /**
35 * Utility functions for looking a S-expression keys. This class will move when
36 * it finds a better home!
37 * <p>
38 * Format documented here:
39 * http://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob;f=agent/keyformat.txt;h=42c4b1f06faf1bbe71ffadc2fee0fad6bec91a97;hb=refs/heads/master
40 * </p>
41 */
42 class SXprUtils {
43 private static int readLength(InputStream in, int ch) throws IOException {
44 int len = ch - '0';
45
46 while ((ch = in.read()) >= 0 && ch != ':') {
47 len = len * 10 + ch - '0';
48 }
49
50 return len;
51 }
52
53 static String readString(InputStream in, int ch) throws IOException {
54 int len = readLength(in, ch);
55
56 char[] chars = new char[len];
57
58 for (int i = 0; i != chars.length; i++) {
59 chars[i] = (char) in.read();
60 }
61
62 return new String(chars);
63 }
64
65 static byte[] readBytes(InputStream in, int ch) throws IOException {
66 int len = readLength(in, ch);
67
68 byte[] data = new byte[len];
69
70 Streams.readFully(in, data);
71
72 return data;
73 }
74
75 static S2K parseS2K(InputStream in) throws IOException {
76 skipOpenParenthesis(in);
77
78 // Algorithm is hard-coded to SHA1 below anyway.
79 readString(in, in.read());
80 byte[] iv = readBytes(in, in.read());
81 final long iterationCount = Long.parseLong(readString(in, in.read()));
82
83 skipCloseParenthesis(in);
84
85 // we have to return the actual iteration count provided.
86 S2K s2k = new S2K(HashAlgorithmTags.SHA1, iv, (int) iterationCount) {
87 @Override
88 public long getIterationCount() {
89 return iterationCount;
90 }
91 };
92
93 return s2k;
94 }
95
96 static void skipOpenParenthesis(InputStream in) throws IOException {
97 int ch = in.read();
98 if (ch != '(') {
99 throw new IOException(
100 "unknown character encountered: " + (char) ch); //$NON-NLS-1$
101 }
102 }
103
104 static void skipCloseParenthesis(InputStream in) throws IOException {
105 int ch = in.read();
106 if (ch != ')') {
107 throw new IOException("unknown character encountered"); //$NON-NLS-1$
108 }
109 }
110 }