ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/gvpe/src/hkdf.C
(Generate patch)

Comparing gvpe/src/hkdf.C (file contents):
Revision 1.4 by root, Fri Sep 12 10:20:08 2014 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
… …
35 35
36#include <openssl/opensslv.h> 36#include <openssl/opensslv.h>
37#include <openssl/rand.h> 37#include <openssl/rand.h>
38#include <openssl/hmac.h> 38#include <openssl/hmac.h>
39 39
40#include "crypto.h"
40#include "util.h" 41#include "util.h"
41#include "hkdf.h" 42#include "hkdf.h"
42 43
43// openssl 0.9.8 compatibility
44#if OPENSSL_VERSION_NUMBER < 0x10100000
45 #define require101(exp) exp
46#else
47 #define require101(exp) require (exp)
48#endif
49
50hkdf::hkdf (const void *salt, int len, const EVP_MD *xtr_hash) 44hkdf::hkdf (const void *salt, int len, const EVP_MD *xtr_hash)
45: salt (salt), salt_len (len)
51{ 46{
52 HMAC_CTX_init (&ctx); 47 ctx.init (salt, salt_len, xtr_hash);
53
54 if (!salt)
55 {
56 memset (prk, 0, sizeof prk);
57 salt = prk;
58 len = EVP_MD_size (xtr_hash);
59 }
60
61 require101 (HMAC_Init_ex (&ctx, salt, len, xtr_hash, 0));
62}
63
64hkdf::~hkdf ()
65{
66 HMAC_CTX_cleanup (&ctx);
67} 48}
68 49
69void 50void
70hkdf::extract (const void *ikm, int len) 51hkdf::extract (const void *ikm, int len)
71{ 52{
72 require101 (HMAC_Update (&ctx, (u8 *)ikm, len)); 53 ctx.add (ikm, len);
73} 54}
74 55
75void 56void
76hkdf::extract_done (const EVP_MD *prf_hash) 57hkdf::extract_done (const EVP_MD *prf_hash)
77{ 58{
78 require101 (HMAC_Final (&ctx, prk, 0)); 59 ctx.digest (prk);
79 require101 (HMAC_Init_ex (&ctx, 0, 0, prf_hash, 0)); 60 ctx.init (salt, salt_len, prf_hash);
80} 61}
81 62
82void 63void
83hkdf::expand (void *okm, int len, const void *info, int infolen) 64hkdf::expand (void *okm, int len, const void *info, int infolen)
84{ 65{
85 u8 tn[sizeof prk]; 66 u8 tn[sizeof prk];
86 u8 iter = 0; 67 u8 iter = 0;
87 int md_size = HMAC_size (&ctx); 68 int md_size = ctx.size ();
88 69
89 while (len) 70 while (len)
90 { 71 {
91 require101 (HMAC_Init_ex (&ctx, prk, md_size, 0, 0)); 72 ctx.init (prk, md_size);
92 73
93 if (iter) 74 if (iter)
94 require101 (HMAC_Update (&ctx, tn, md_size)); 75 ctx.add (tn, md_size);
95 76
96 require101 (HMAC_Update (&ctx, (u8 *)info, infolen)); 77 ctx.add (info, infolen);
97 78
98 ++iter; 79 ++iter;
99 require (iter); 80 require (iter);
100 81
101 require101 (HMAC_Update (&ctx, &iter, 1)); 82 ctx.add (&iter, 1);
102 83 ctx.digest (tn);
103 require101 (HMAC_Final (&ctx, tn, 0));
104 84
105 int ol = len > md_size ? md_size : len; 85 int ol = len > md_size ? md_size : len;
106 86
107 memcpy (okm, tn, ol); 87 memcpy (okm, tn, ol);
108 88
… …
125 u8 s[256]; 105 u8 s[256];
126 106
127 unhex (const char *hs) 107 unhex (const char *hs)
128 { 108 {
129 l = 0; 109 l = 0;
130 p = 0; 110 p = s;
131 111
132 if (!hs) 112 if (!hs)
133 return; 113 return;
134
135 p = s;
136 114
137 while (*hs) 115 while (*hs)
138 { 116 {
139 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;
140 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;

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines