1/**********************************************************************
2 * keywrap.c *
3 * Copyright (c) 2005-2006 Cryptocom LTD *
4 * This file is distributed under the same license as OpenSSL *
5 * *
6 * Implementation of CryptoPro key wrap algorithm, as defined in *
7 * RFC 4357 p 6.3 and 6.4 *
8 * Doesn't need OpenSSL *
9 **********************************************************************/
10#include <string.h>
11#include "gost89.h"
12#include "gost_keywrap.h"
13
| 1/**********************************************************************
2 * keywrap.c *
3 * Copyright (c) 2005-2006 Cryptocom LTD *
4 * This file is distributed under the same license as OpenSSL *
5 * *
6 * Implementation of CryptoPro key wrap algorithm, as defined in *
7 * RFC 4357 p 6.3 and 6.4 *
8 * Doesn't need OpenSSL *
9 **********************************************************************/
10#include <string.h>
11#include "gost89.h"
12#include "gost_keywrap.h"
13
|
14/* Diversifies key using random UserKey Material
15 * Implements RFC 4357 p 6.5 key diversification algorithm
16 *
| 14/*-
15 * Diversifies key using random UserKey Material
16 * Implements RFC 4357 p 6.5 key diversification algorithm
17 *
|
17 * inputKey - 32byte key to be diversified
18 * ukm - 8byte user key material
| 18 * inputKey - 32byte key to be diversified
19 * ukm - 8byte user key material
|
19 * outputKey - 32byte buffer to store diversified key
| 20 * outputKey - 32byte buffer to store diversified key
|
20 *
21 */
| 21 *
22 */
|
22void keyDiversifyCryptoPro(gost_ctx *ctx,const unsigned char *inputKey, const unsigned char *ukm, unsigned char *outputKey)
23 {
| 23void keyDiversifyCryptoPro(gost_ctx * ctx, const unsigned char *inputKey,
24 const unsigned char *ukm, unsigned char *outputKey)
25{
|
24
| 26
|
25 u4 k,s1,s2;
26 int i,j,mask;
27 unsigned char S[8];
28 memcpy(outputKey,inputKey,32);
29 for (i=0;i<8;i++)
30 {
31 /* Make array of integers from key */
32 /* Compute IV S*/
33 s1=0,s2=0;
34 for (j=0,mask=1;j<8;j++,mask<<=1)
35 {
36 k=((u4)outputKey[4*j])|(outputKey[4*j+1]<<8)|
37 (outputKey[4*j+2]<<16)|(outputKey[4*j+3]<<24);
38 if (mask & ukm[i])
39 {
40 s1+=k;
41 }
42 else
43 {
44 s2+=k;
45 }
46 }
47 S[0]=(unsigned char)(s1&0xff);
48 S[1]=(unsigned char)((s1>>8)&0xff);
49 S[2]=(unsigned char)((s1>>16)&0xff);
50 S[3]=(unsigned char)((s1>>24)&0xff);
51 S[4]=(unsigned char)(s2&0xff);
52 S[5]=(unsigned char)((s2>>8)&0xff);
53 S[6]=(unsigned char)((s2>>16)&0xff);
54 S[7]=(unsigned char)((s2>>24)&0xff);
55 gost_key(ctx,outputKey);
56 gost_enc_cfb(ctx,S,outputKey,outputKey,4);
57 }
58 }
59
| 27 u4 k, s1, s2;
28 int i, j, mask;
29 unsigned char S[8];
30 memcpy(outputKey, inputKey, 32);
31 for (i = 0; i < 8; i++) {
32 /* Make array of integers from key */
33 /* Compute IV S */
34 s1 = 0, s2 = 0;
35 for (j = 0, mask = 1; j < 8; j++, mask <<= 1) {
36 k = ((u4) outputKey[4 * j]) | (outputKey[4 * j + 1] << 8) |
37 (outputKey[4 * j + 2] << 16) | (outputKey[4 * j + 3] << 24);
38 if (mask & ukm[i]) {
39 s1 += k;
40 } else {
41 s2 += k;
42 }
43 }
44 S[0] = (unsigned char)(s1 & 0xff);
45 S[1] = (unsigned char)((s1 >> 8) & 0xff);
46 S[2] = (unsigned char)((s1 >> 16) & 0xff);
47 S[3] = (unsigned char)((s1 >> 24) & 0xff);
48 S[4] = (unsigned char)(s2 & 0xff);
49 S[5] = (unsigned char)((s2 >> 8) & 0xff);
50 S[6] = (unsigned char)((s2 >> 16) & 0xff);
51 S[7] = (unsigned char)((s2 >> 24) & 0xff);
52 gost_key(ctx, outputKey);
53 gost_enc_cfb(ctx, S, outputKey, outputKey, 4);
54 }
55}
|
60
| 56
|
61/*
| 57/*-
|
62 * Wraps key using RFC 4357 6.3
| 58 * Wraps key using RFC 4357 6.3
|
63 * ctx - gost encryption context, initialized with some S-boxes
| 59 * ctx - gost encryption context, initialized with some S-boxes
|
64 * keyExchangeKey (KEK) 32-byte (256-bit) shared key
| 60 * keyExchangeKey (KEK) 32-byte (256-bit) shared key
|
65 * ukm - 8 byte (64 bit) user key material,
| 61 * ukm - 8 byte (64 bit) user key material,
|
66 * sessionKey - 32-byte (256-bit) key to be wrapped
67 * wrappedKey - 44-byte buffer to store wrapped key
| 62 * sessionKey - 32-byte (256-bit) key to be wrapped
63 * wrappedKey - 44-byte buffer to store wrapped key
|
68 */
| 64 */
|
69
| 65
|
70int keyWrapCryptoPro(gost_ctx *ctx,const unsigned char *keyExchangeKey, const unsigned char *ukm,
71 const unsigned char *sessionKey, unsigned char *wrappedKey)
72 {
73 unsigned char kek_ukm[32];
74 keyDiversifyCryptoPro(ctx,keyExchangeKey,ukm,kek_ukm);
75 gost_key(ctx,kek_ukm);
76 memcpy(wrappedKey,ukm,8);
77 gost_enc(ctx,sessionKey,wrappedKey+8,4);
78 gost_mac_iv(ctx,32,ukm,sessionKey,32,wrappedKey+40);
79 return 1;
80 }
81/*
| 66int keyWrapCryptoPro(gost_ctx * ctx, const unsigned char *keyExchangeKey,
67 const unsigned char *ukm,
68 const unsigned char *sessionKey,
69 unsigned char *wrappedKey)
70{
71 unsigned char kek_ukm[32];
72 keyDiversifyCryptoPro(ctx, keyExchangeKey, ukm, kek_ukm);
73 gost_key(ctx, kek_ukm);
74 memcpy(wrappedKey, ukm, 8);
75 gost_enc(ctx, sessionKey, wrappedKey + 8, 4);
76 gost_mac_iv(ctx, 32, ukm, sessionKey, 32, wrappedKey + 40);
77 return 1;
78}
79
80/*-
|
82 * Unwraps key using RFC 4357 6.4
| 81 * Unwraps key using RFC 4357 6.4
|
83 * ctx - gost encryption context, initialized with some S-boxes
| 82 * ctx - gost encryption context, initialized with some S-boxes
|
84 * keyExchangeKey 32-byte shared key
85 * wrappedKey 44 byte key to be unwrapped (concatenation of 8-byte UKM,
| 83 * keyExchangeKey 32-byte shared key
84 * wrappedKey 44 byte key to be unwrapped (concatenation of 8-byte UKM,
|
86 * 32 byte encrypted key and 4 byte MAC
87 *
| 85 * 32 byte encrypted key and 4 byte MAC
86 *
|
88 * sessionKEy - 32byte buffer to store sessionKey in
89 * Returns 1 if key is decrypted successfully, and 0 if MAC doesn't match
| 87 * sessionKEy - 32byte buffer to store sessionKey in
88 * Returns 1 if key is decrypted successfully, and 0 if MAC doesn't match
|
90 */
| 89 */
|
91
| 90
|
92int keyUnwrapCryptoPro(gost_ctx *ctx,const unsigned char *keyExchangeKey,
93 const unsigned char *wrappedKey, unsigned char *sessionKey)
94 {
95 unsigned char kek_ukm[32],cek_mac[4];
96 keyDiversifyCryptoPro(ctx,keyExchangeKey,wrappedKey
97 /* First 8 bytes of wrapped Key is ukm */
98 ,kek_ukm);
99 gost_key(ctx,kek_ukm);
100 gost_dec(ctx,wrappedKey+8,sessionKey,4);
101 gost_mac_iv(ctx,32,wrappedKey,sessionKey,32,cek_mac);
102 if (memcmp(cek_mac,wrappedKey+40,4))
103 {
104 return 0;
105 }
106 return 1;
107 }
108
109
| 91int keyUnwrapCryptoPro(gost_ctx * ctx, const unsigned char *keyExchangeKey,
92 const unsigned char *wrappedKey,
93 unsigned char *sessionKey)
94{
95 unsigned char kek_ukm[32], cek_mac[4];
96 keyDiversifyCryptoPro(ctx, keyExchangeKey, wrappedKey
97 /* First 8 bytes of wrapped Key is ukm */
98 , kek_ukm);
99 gost_key(ctx, kek_ukm);
100 gost_dec(ctx, wrappedKey + 8, sessionKey, 4);
101 gost_mac_iv(ctx, 32, wrappedKey, sessionKey, 32, cek_mac);
102 if (memcmp(cek_mac, wrappedKey + 40, 4)) {
103 return 0;
104 }
105 return 1;
106}
|
| |