1 /* 2 * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package sun.security.provider; 27 28 import java.util.Objects; 29 30 import jdk.internal.HotSpotIntrinsicCandidate; 31 import static sun.security.provider.ByteArrayAccess.*; 32 33 /** 34 * This class implements the Secure Hash Algorithm SHA-256 developed by 35 * the National Institute of Standards and Technology along with the 36 * National Security Agency. 37 * 38 * <p>It implements java.security.MessageDigestSpi, and can be used 39 * through Java Cryptography Architecture (JCA), as a pluggable 40 * MessageDigest implementation. 41 * 42 * @since 1.4.2 43 * @author Valerie Peng 44 * @author Andreas Sterbenz 45 */ 46 abstract class SHA2 extends DigestBase { 47 48 private static final int ITERATION = 64; 49 // Constants for each round 50 private static final int[] ROUND_CONSTS = { 51 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 52 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5, 53 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 54 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 55 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 56 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 57 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 58 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, 59 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 60 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 61 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 62 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, 63 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 64 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3, 65 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 66 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 67 }; 68 69 // buffer used by implCompress() 70 private int[] W; 71 72 // state of this object 73 private int[] state; 74 75 // initial state value. different between SHA-224 and SHA-256 76 private final int[] initialHashes; 77 78 /** 79 * Creates a new SHA object. 80 */ 81 SHA2(String name, int digestLength, int[] initialHashes) { 82 super(name, digestLength, 64); 83 this.initialHashes = initialHashes; 84 state = new int[8]; 85 W = new int[64]; 86 implReset(); 87 } 88 89 /** 90 * Resets the buffers and hash value to start a new hash. 91 */ 92 void implReset() { 93 System.arraycopy(initialHashes, 0, state, 0, state.length); 94 } 95 96 void implDigest(byte[] out, int ofs) { 97 long bitsProcessed = bytesProcessed << 3; 98 99 int index = (int)bytesProcessed & 0x3f; 100 int padLen = (index < 56) ? (56 - index) : (120 - index); 101 engineUpdate(padding, 0, padLen); 102 103 i2bBig4((int)(bitsProcessed >>> 32), buffer, 56); 104 i2bBig4((int)bitsProcessed, buffer, 60); 105 implCompress(buffer, 0); 106 107 i2bBig(state, 0, out, ofs, engineGetDigestLength()); 108 } 109 110 /** 111 * logical function ch(x,y,z) as defined in spec: 112 * @return (x and y) xor ((complement x) and z) 113 * @param x int 114 * @param y int 115 * @param z int 116 */ 117 private static int lf_ch(int x, int y, int z) { 118 return (x & y) ^ ((~x) & z); 119 } 120 121 /** 122 * logical function maj(x,y,z) as defined in spec: 123 * @return (x and y) xor (x and z) xor (y and z) 124 * @param x int 125 * @param y int 126 * @param z int 127 */ 128 private static int lf_maj(int x, int y, int z) { 129 return (x & y) ^ (x & z) ^ (y & z); 130 } 131 132 /** 133 * logical function R(x,s) - right shift 134 * @return x right shift for s times 135 * @param x int 136 * @param s int 137 */ 138 private static int lf_R( int x, int s ) { 139 return (x >>> s); 140 } 141 142 /** 143 * logical function S(x,s) - right rotation 144 * @return x circular right shift for s times 145 * @param x int 146 * @param s int 147 */ 148 private static int lf_S(int x, int s) { 149 return (x >>> s) | (x << (32 - s)); 150 } 151 152 /** 153 * logical function sigma0(x) - xor of results of right rotations 154 * @return S(x,2) xor S(x,13) xor S(x,22) 155 * @param x int 156 */ 157 private static int lf_sigma0(int x) { 158 return lf_S(x, 2) ^ lf_S(x, 13) ^ lf_S(x, 22); 159 } 160 161 /** 162 * logical function sigma1(x) - xor of results of right rotations 163 * @return S(x,6) xor S(x,11) xor S(x,25) 164 * @param x int 165 */ 166 private static int lf_sigma1(int x) { 167 return lf_S( x, 6 ) ^ lf_S( x, 11 ) ^ lf_S( x, 25 ); 168 } 169 170 /** 171 * logical function delta0(x) - xor of results of right shifts/rotations 172 * @return int 173 * @param x int 174 */ 175 private static int lf_delta0(int x) { 176 return lf_S(x, 7) ^ lf_S(x, 18) ^ lf_R(x, 3); 177 } 178 179 /** 180 * logical function delta1(x) - xor of results of right shifts/rotations 181 * @return int 182 * @param x int 183 */ 184 private static int lf_delta1(int x) { 185 return lf_S(x, 17) ^ lf_S(x, 19) ^ lf_R(x, 10); 186 } 187 188 /** 189 * Process the current block to update the state variable state. 190 */ 191 void implCompress(byte[] buf, int ofs) { 192 implCompressCheck(buf, ofs); 193 implCompress0(buf, ofs); 194 } 195 196 private void implCompressCheck(byte[] buf, int ofs) { 197 Objects.requireNonNull(buf); 198 199 // The checks performed by the method 'b2iBig64' 200 // are sufficient for the case when the method 201 // 'implCompressImpl' is replaced with a compiler 202 // intrinsic. 203 b2iBig64(buf, ofs, W); 204 } 205 206 // The method 'implCompressImpl' seems not to use its parameters. 207 // The method can, however, be replaced with a compiler intrinsic 208 // that operates directly on the array 'buf' (starting from 209 // offset 'ofs') and not on array 'W', therefore 'buf' and 'ofs' 210 // must be passed as parameter to the method. 211 @HotSpotIntrinsicCandidate 212 private void implCompress0(byte[] buf, int ofs) { 213 // The first 16 ints are from the byte stream, compute the rest of 214 // the W[]'s 215 for (int t = 16; t < ITERATION; t++) { 216 W[t] = lf_delta1(W[t-2]) + W[t-7] + lf_delta0(W[t-15]) 217 + W[t-16]; 218 } 219 220 int a = state[0]; 221 int b = state[1]; 222 int c = state[2]; 223 int d = state[3]; 224 int e = state[4]; 225 int f = state[5]; 226 int g = state[6]; 227 int h = state[7]; 228 229 for (int i = 0; i < ITERATION; i++) { 230 int T1 = h + lf_sigma1(e) + lf_ch(e,f,g) + ROUND_CONSTS[i] + W[i]; 231 int T2 = lf_sigma0(a) + lf_maj(a,b,c); 232 h = g; 233 g = f; 234 f = e; 235 e = d + T1; 236 d = c; 237 c = b; 238 b = a; 239 a = T1 + T2; 240 } 241 state[0] += a; 242 state[1] += b; 243 state[2] += c; 244 state[3] += d; 245 state[4] += e; 246 state[5] += f; 247 state[6] += g; 248 state[7] += h; 249 } 250 251 public Object clone() throws CloneNotSupportedException { 252 SHA2 copy = (SHA2) super.clone(); 253 copy.state = copy.state.clone(); 254 copy.W = new int[64]; 255 return copy; 256 } 257 258 /** 259 * SHA-224 implementation class. 260 */ 261 public static final class SHA224 extends SHA2 { 262 private static final int[] INITIAL_HASHES = { 263 0xc1059ed8, 0x367cd507, 0x3070dd17, 0xf70e5939, 264 0xffc00b31, 0x68581511, 0x64f98fa7, 0xbefa4fa4 265 }; 266 267 public SHA224() { 268 super("SHA-224", 28, INITIAL_HASHES); 269 } 270 } 271 272 /** 273 * SHA-256 implementation class. 274 */ 275 public static final class SHA256 extends SHA2 { 276 private static final int[] INITIAL_HASHES = { 277 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 278 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 279 }; 280 281 public SHA256() { 282 super("SHA-256", 32, INITIAL_HASHES); 283 } 284 } 285 }