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Comparing gvpe/src/hkdf.C (file contents):
Revision 1.1 by root, Tue Jul 16 16:44:36 2013 UTC vs.
Revision 1.6 by root, Thu Jun 30 16:31:00 2016 UTC

1/* 1/*
2 hkdf.C -- RFC 5869 HKDF implementation 2 hkdf.C -- RFC 5869 HKDF implementation
3 Copyright (C) 2013 Marc Lehmann <gvpe@schmorp.de> 3 Copyright (C) 2013,2016 Marc Lehmann <gvpe@schmorp.de>
4 4
5 This file is part of GVPE. 5 This file is part of GVPE.
6 6
7 GVPE is free software; you can redistribute it and/or modify it 7 GVPE is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the 8 under the terms of the GNU General Public License as published by the
… …
31 31
32#include "config.h" 32#include "config.h"
33 33
34#include <cstring> 34#include <cstring>
35 35
36#include <openssl/opensslv.h>
36#include <openssl/rand.h> 37#include <openssl/rand.h>
37#include <openssl/hmac.h> 38#include <openssl/hmac.h>
38 39
40#include "crypto.h"
39#include "util.h" 41#include "util.h"
40#include "hkdf.h" 42#include "hkdf.h"
41 43
42hkdf::hkdf (const void *salt, int len, const EVP_MD *hash) 44hkdf::hkdf (const void *salt, int len, const EVP_MD *xtr_hash)
45: salt (salt), salt_len (len)
43{ 46{
44 HMAC_CTX_init (&ctx); 47 ctx.init (salt, salt_len, xtr_hash);
45
46 if (!salt)
47 {
48 memset (prk, 0, sizeof prk);
49 salt = prk;
50 len = EVP_MD_size (hash);
51 }
52
53 require (HMAC_Init_ex (&ctx, salt, len, hash, 0));
54}
55
56hkdf::~hkdf ()
57{
58 HMAC_CTX_cleanup (&ctx);
59} 48}
60 49
61void 50void
62hkdf::extract (const void *ikm, int len) 51hkdf::extract (const void *ikm, int len)
63{ 52{
64 require (HMAC_Update (&ctx, (u8 *)ikm, len)); 53 ctx.add (ikm, len);
65} 54}
66 55
67void 56void
68hkdf::extract_done () 57hkdf::extract_done (const EVP_MD *prf_hash)
69{ 58{
70 require (HMAC_Final (&ctx, prk, 0)); 59 ctx.digest (prk);
60 ctx.init (salt, salt_len, prf_hash);
71} 61}
72 62
73void 63void
74hkdf::expand (void *okm, int len, const void *info, int infolen) 64hkdf::expand (void *okm, int len, const void *info, int infolen)
75{ 65{
76 u8 tn[sizeof prk]; 66 u8 tn[sizeof prk];
77 u8 iter = 0; 67 u8 iter = 0;
78 int md_size = HMAC_size (&ctx); 68 int md_size = ctx.size ();
79 69
80 while (len) 70 while (len)
81 { 71 {
82 require (HMAC_Init_ex (&ctx, prk, md_size, 0, 0)); 72 ctx.init (prk, md_size);
83 73
84 if (iter) 74 if (iter)
85 require (HMAC_Update (&ctx, tn, md_size)); 75 ctx.add (tn, md_size);
86 76
87 require (HMAC_Update (&ctx, (u8 *)info, infolen)); 77 ctx.add (info, infolen);
88
89 78
90 ++iter; 79 ++iter;
91 require (iter); 80 require (iter);
92 81
93 require (HMAC_Update (&ctx, &iter, 1)); 82 ctx.add (&iter, 1);
94 83 ctx.digest (tn);
95 require (HMAC_Final (&ctx, tn, 0));
96 84
97 int ol = len > md_size ? md_size : len; 85 int ol = len > md_size ? md_size : len;
98 86
99 memcpy (okm, tn, ol); 87 memcpy (okm, tn, ol);
100 88
… …
117 u8 s[256]; 105 u8 s[256];
118 106
119 unhex (const char *hs) 107 unhex (const char *hs)
120 { 108 {
121 l = 0; 109 l = 0;
122 p = 0; 110 p = s;
123 111
124 if (!hs) 112 if (!hs)
125 return; 113 return;
126
127 p = s;
128 114
129 while (*hs) 115 while (*hs)
130 { 116 {
131 int d1 = *hs >= '0' && *hs <= '9' ? *hs - '0' : *hs - 'a' + 10; ++hs; 117 int d1 = *hs >= '0' && *hs <= '9' ? *hs - '0' : *hs - 'a' + 10; ++hs;
132 int d2 = *hs >= '0' && *hs <= '9' ? *hs - '0' : *hs - 'a' + 10; ++hs; 118 int d2 = *hs >= '0' && *hs <= '9' ? *hs - '0' : *hs - 'a' + 10; ++hs;

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