| 1 | /* |
| 2 | * hmac.c: routines to compute HMAC-SHA-1/224/256/384/512 digests |
| 3 | * |
| 4 | * Ref: FIPS PUB 198 The Keyed-Hash Message Authentication Code |
| 5 | * |
| 6 | * Copyright (C) 2003-2005 Mark Shelor, All Rights Reserved |
| 7 | * |
| 8 | * Version: 5.32 |
| 9 | * Fri Dec 2 02:32:20 MST 2005 |
| 10 | * |
| 11 | */ |
| 12 | |
| 13 | #include <stdio.h> |
| 14 | #include <stdlib.h> |
| 15 | #include <string.h> |
| 16 | #include "hmac.h" |
| 17 | #include "sha.h" |
| 18 | |
| 19 | /* hmacopen: creates a new HMAC-SHA digest object */ |
| 20 | HMAC *hmacopen(alg, key, keylen) |
| 21 | int alg; |
| 22 | unsigned char *key; |
| 23 | unsigned int keylen; |
| 24 | { |
| 25 | unsigned int i; |
| 26 | HMAC *h; |
| 27 | |
| 28 | SHA_newz(0, h, 1, HMAC); |
| 29 | if (h == NULL) |
| 30 | return(NULL); |
| 31 | if ((h->isha = shaopen(alg)) == NULL) { |
| 32 | SHA_free(h); |
| 33 | return(NULL); |
| 34 | } |
| 35 | if ((h->osha = shaopen(alg)) == NULL) { |
| 36 | shaclose(h->isha); |
| 37 | SHA_free(h); |
| 38 | return(NULL); |
| 39 | } |
| 40 | if (keylen <= h->osha->blocksize / 8) |
| 41 | memcpy(h->key, key, keylen); |
| 42 | else { |
| 43 | if ((h->ksha = shaopen(alg)) == NULL) { |
| 44 | shaclose(h->isha); |
| 45 | shaclose(h->osha); |
| 46 | SHA_free(h); |
| 47 | return(NULL); |
| 48 | } |
| 49 | shawrite(key, keylen * 8, h->ksha); |
| 50 | shafinish(h->ksha); |
| 51 | memcpy(h->key, shadigest(h->ksha), h->ksha->digestlen); |
| 52 | shaclose(h->ksha); |
| 53 | } |
| 54 | for (i = 0; i < h->osha->blocksize / 8; i++) |
| 55 | h->key[i] ^= 0x5c; |
| 56 | shawrite(h->key, h->osha->blocksize, h->osha); |
| 57 | for (i = 0; i < h->isha->blocksize / 8; i++) |
| 58 | h->key[i] ^= (0x5c ^ 0x36); |
| 59 | shawrite(h->key, h->isha->blocksize, h->isha); |
| 60 | memset(h->key, 0, sizeof(h->key)); |
| 61 | return(h); |
| 62 | } |
| 63 | |
| 64 | /* hmacwrite: triggers a state update using data in bitstr/bitcnt */ |
| 65 | unsigned long hmacwrite(bitstr, bitcnt, h) |
| 66 | unsigned char *bitstr; |
| 67 | unsigned long bitcnt; |
| 68 | HMAC *h; |
| 69 | { |
| 70 | return(shawrite(bitstr, bitcnt, h->isha)); |
| 71 | } |
| 72 | |
| 73 | /* hmacfinish: computes final digest state */ |
| 74 | void hmacfinish(h) |
| 75 | HMAC *h; |
| 76 | { |
| 77 | shafinish(h->isha); |
| 78 | shawrite(shadigest(h->isha), h->isha->digestlen * 8, h->osha); |
| 79 | shaclose(h->isha); |
| 80 | shafinish(h->osha); |
| 81 | } |
| 82 | |
| 83 | /* hmacdigest: returns pointer to digest (binary) */ |
| 84 | unsigned char *hmacdigest(h) |
| 85 | HMAC *h; |
| 86 | { |
| 87 | return(shadigest(h->osha)); |
| 88 | } |
| 89 | |
| 90 | /* hmachex: returns pointer to digest (hexadecimal) */ |
| 91 | char *hmachex(h) |
| 92 | HMAC *h; |
| 93 | { |
| 94 | return(shahex(h->osha)); |
| 95 | } |
| 96 | |
| 97 | /* hmacbase64: returns pointer to digest (Base 64) */ |
| 98 | char *hmacbase64(h) |
| 99 | HMAC *h; |
| 100 | { |
| 101 | return(shabase64(h->osha)); |
| 102 | } |
| 103 | |
| 104 | /* hmacclose: de-allocates digest object */ |
| 105 | int hmacclose(h) |
| 106 | HMAC *h; |
| 107 | { |
| 108 | shaclose(h->osha); |
| 109 | if (h != NULL) { |
| 110 | memset(h, 0, sizeof(HMAC)); |
| 111 | SHA_free(h); |
| 112 | } |
| 113 | return(0); |
| 114 | } |