1/* 2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10/* 11 * IDEA low level APIs are deprecated for public use, but still ok for internal 12 * use where we're using them to implement the higher level EVP interface, as is 13 * the case here. 14 */ 15#include "internal/deprecated.h" 16 17#include <openssl/idea.h> 18#include "idea_local.h" 19 20static IDEA_INT inverse(unsigned int xin); 21void IDEA_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks) 22{ 23 int i; 24 register IDEA_INT *kt, *kf, r0, r1, r2; 25 26 kt = &(ks->data[0][0]); 27 n2s(key, kt[0]); 28 n2s(key, kt[1]); 29 n2s(key, kt[2]); 30 n2s(key, kt[3]); 31 n2s(key, kt[4]); 32 n2s(key, kt[5]); 33 n2s(key, kt[6]); 34 n2s(key, kt[7]); 35 36 kf = kt; 37 kt += 8; 38 for (i = 0; i < 6; i++) { 39 r2 = kf[1]; 40 r1 = kf[2]; 41 *(kt++) = ((r2 << 9) | (r1 >> 7)) & 0xffff; 42 r0 = kf[3]; 43 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 44 r1 = kf[4]; 45 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 46 r0 = kf[5]; 47 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 48 r1 = kf[6]; 49 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 50 r0 = kf[7]; 51 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 52 r1 = kf[0]; 53 if (i >= 5) 54 break; 55 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 56 *(kt++) = ((r1 << 9) | (r2 >> 7)) & 0xffff; 57 kf += 8; 58 } 59} 60 61void IDEA_set_decrypt_key(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk) 62{ 63 int r; 64 register IDEA_INT *fp, *tp, t; 65 66 tp = &(dk->data[0][0]); 67 fp = &(ek->data[8][0]); 68 for (r = 0; r < 9; r++) { 69 *(tp++) = inverse(fp[0]); 70 *(tp++) = ((int)(0x10000L - fp[2]) & 0xffff); 71 *(tp++) = ((int)(0x10000L - fp[1]) & 0xffff); 72 *(tp++) = inverse(fp[3]); 73 if (r == 8) 74 break; 75 fp -= 6; 76 *(tp++) = fp[4]; 77 *(tp++) = fp[5]; 78 } 79 80 tp = &(dk->data[0][0]); 81 t = tp[1]; 82 tp[1] = tp[2]; 83 tp[2] = t; 84 85 t = tp[49]; 86 tp[49] = tp[50]; 87 tp[50] = t; 88} 89 90/* taken directly from the 'paper' I'll have a look at it later */ 91static IDEA_INT inverse(unsigned int xin) 92{ 93 long n1, n2, q, r, b1, b2, t; 94 95 if (xin == 0) 96 b2 = 0; 97 else { 98 n1 = 0x10001; 99 n2 = xin; 100 b2 = 1; 101 b1 = 0; 102 103 do { 104 r = (n1 % n2); 105 q = (n1 - r) / n2; 106 if (r == 0) { 107 if (b2 < 0) 108 b2 = 0x10001 + b2; 109 } else { 110 n1 = n2; 111 n2 = r; 112 t = b2; 113 b2 = b1 - q * b2; 114 b1 = t; 115 } 116 } while (r != 0); 117 } 118 return (IDEA_INT)b2; 119} 120