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 <inttypes.h> 16#include "internal/deprecated.h" 17 18#include <openssl/idea.h> 19#include "idea_local.h" 20 21static IDEA_INT inverse(unsigned int xin); 22void IDEA_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks) 23{ 24 int i; 25 register IDEA_INT *kt, *kf, r0, r1, r2; 26 27 kt = &(ks->data[0][0]); 28 n2s(key, kt[0]); 29 n2s(key, kt[1]); 30 n2s(key, kt[2]); 31 n2s(key, kt[3]); 32 n2s(key, kt[4]); 33 n2s(key, kt[5]); 34 n2s(key, kt[6]); 35 n2s(key, kt[7]); 36 37 kf = kt; 38 kt += 8; 39 for (i = 0; i < 6; i++) { 40 r2 = kf[1]; 41 r1 = kf[2]; 42 *(kt++) = ((r2 << 9) | (r1 >> 7)) & 0xffff; 43 r0 = kf[3]; 44 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 45 r1 = kf[4]; 46 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 47 r0 = kf[5]; 48 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 49 r1 = kf[6]; 50 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 51 r0 = kf[7]; 52 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 53 r1 = kf[0]; 54 if (i >= 5) 55 break; 56 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 57 *(kt++) = ((r1 << 9) | (r2 >> 7)) & 0xffff; 58 kf += 8; 59 } 60} 61 62void IDEA_set_decrypt_key(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk) 63{ 64 int r; 65 register IDEA_INT *fp, *tp, t; 66 67 tp = &(dk->data[0][0]); 68 fp = &(ek->data[8][0]); 69 for (r = 0; r < 9; r++) { 70 *(tp++) = inverse(fp[0]); 71 *(tp++) = ((int)(0x10000L - fp[2]) & 0xffff); 72 *(tp++) = ((int)(0x10000L - fp[1]) & 0xffff); 73 *(tp++) = inverse(fp[3]); 74 if (r == 8) 75 break; 76 fp -= 6; 77 *(tp++) = fp[4]; 78 *(tp++) = fp[5]; 79 } 80 81 tp = &(dk->data[0][0]); 82 t = tp[1]; 83 tp[1] = tp[2]; 84 tp[2] = t; 85 86 t = tp[49]; 87 tp[49] = tp[50]; 88 tp[50] = t; 89} 90 91/* taken directly from the 'paper' I'll have a look at it later */ 92static IDEA_INT inverse(unsigned int xin) 93{ 94 int32_t n1, n2, q, r, b1, b2, t; 95 96 if (xin == 0) 97 b2 = 0; 98 else { 99 n1 = 0x10001; 100 n2 = xin; 101 b2 = 1; 102 b1 = 0; 103 104 do { 105 r = (n1 % n2); 106 q = (n1 - r) / n2; 107 if (r == 0) { 108 if (b2 < 0) 109 b2 = 0x10001 + b2; 110 } else { 111 n1 = n2; 112 n2 = r; 113 t = b2; 114 b2 = b1 - q * b2; 115 b1 = t; 116 } 117 } while (r != 0); 118 } 119 return (IDEA_INT)b2; 120} 121