/src/dropbear/libtomcrypt/src/mac/hmac/hmac_init.c

Source (jump to first uncovered line)
/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 */
#include "tomcrypt.h"

/**
  @file hmac_init.c
  HMAC support, initialize state, Tom St Denis/Dobes Vandermeer
*/

#ifdef LTC_HMAC

#define LTC_HMAC_BLOCKSIZE hash_descriptor[hash].blocksize

/**
   Initialize an HMAC context.
   @param hmac     The HMAC state
   @param hash     The index of the hash you want to use
   @param key      The secret key
   @param keylen   The length of the secret key (octets)
   @return CRYPT_OK if successful
*/
int hmac_init(hmac_state *hmac, int hash, const unsigned char *key, unsigned long keylen)
{
    unsigned char buf[MAXBLOCKSIZE];
    unsigned long hashsize;
    unsigned long i, z;
    int err;

    LTC_ARGCHK(hmac != NULL);
    LTC_ARGCHK(key  != NULL);

    /* valid hash? */
    if ((err = hash_is_valid(hash)) != CRYPT_OK) {
        return err;
    }
    hmac->hash = hash;
    hashsize   = hash_descriptor[hash].hashsize;

    /* valid key length? */
    if (keylen == 0) {
        return CRYPT_INVALID_KEYSIZE;
    }

    /* allocate memory for key */
    hmac->key = XMALLOC(LTC_HMAC_BLOCKSIZE);
    if (hmac->key == NULL) {
       return CRYPT_MEM;
    }

    /* (1) make sure we have a large enough key */
    if(keylen > LTC_HMAC_BLOCKSIZE) {
        z = LTC_HMAC_BLOCKSIZE;
        if ((err = hash_memory(hash, key, keylen, hmac->key, &z)) != CRYPT_OK) {
           goto LBL_ERR;
        }
        keylen = hashsize;
    } else {
        XMEMCPY(hmac->key, key, (size_t)keylen);
    }

    if(keylen < LTC_HMAC_BLOCKSIZE) {
       zeromem((hmac->key) + keylen, (size_t)(LTC_HMAC_BLOCKSIZE - keylen));
    }

    /* Create the initialization vector for step (3) */
    for(i=0; i < LTC_HMAC_BLOCKSIZE;   i++) {
       buf[i] = hmac->key[i] ^ 0x36;
    }

    /* Pre-pend that to the hash data */
    if ((err = hash_descriptor[hash].init(&hmac->md)) != CRYPT_OK) {
       goto LBL_ERR;
    }

    if ((err = hash_descriptor[hash].process(&hmac->md, buf, LTC_HMAC_BLOCKSIZE)) != CRYPT_OK) {
       goto LBL_ERR;
    }
    goto done;
LBL_ERR:
    /* free the key since we failed */
    XFREE(hmac->key);
done:
#ifdef LTC_CLEAN_STACK
   zeromem(buf, LTC_HMAC_BLOCKSIZE);
#endif

   return err;
}

#endif

/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */

Line	Count	Source (jump to first uncovered line)
1		/* LibTomCrypt, modular cryptographic library -- Tom St Denis
2		*
3		* LibTomCrypt is a library that provides various cryptographic
4		* algorithms in a highly modular and flexible manner.
5		*
6		* The library is free for all purposes without any express
7		* guarantee it works.
8		*/
9		#include "tomcrypt.h"
10
11		/**
12		@file hmac_init.c
13		HMAC support, initialize state, Tom St Denis/Dobes Vandermeer
14		*/
15
16		#ifdef LTC_HMAC
17
18	610k	#define LTC_HMAC_BLOCKSIZE hash_descriptor[hash].blocksize
19
20		/**
21		Initialize an HMAC context.
22		@param hmac The HMAC state
23		@param hash The index of the hash you want to use
24		@param key The secret key
25		@param keylen The length of the secret key (octets)
26		@return CRYPT_OK if successful
27		*/
28		int hmac_init(hmac_state hmac, int hash, const unsigned char key, unsigned long keylen)
29	8.71k	{
30	8.71k	unsigned char buf[MAXBLOCKSIZE];
31	8.71k	unsigned long hashsize;
32	8.71k	unsigned long i, z;
33	8.71k	int err;
34
35	8.71k	LTC_ARGCHK(hmac != NULL);
36	8.71k	LTC_ARGCHK(key != NULL);
37
38		/* valid hash? */
39	8.71k	if ((err = hash_is_valid(hash)) != CRYPT_OK) {
40	0	return err;
41	0	}
42	8.71k	hmac->hash = hash;
43	8.71k	hashsize = hash_descriptor[hash].hashsize;
44
45		/* valid key length? */
46	8.71k	if (keylen == 0) {
47	0	return CRYPT_INVALID_KEYSIZE;
48	0	}
49
50		/* allocate memory for key */
51	8.71k	hmac->key = XMALLOC(LTC_HMAC_BLOCKSIZE);
52	8.71k	if (hmac->key == NULL) {
53	0	return CRYPT_MEM;
54	0	}
55
56		/* (1) make sure we have a large enough key */
57	8.71k	if(keylen > LTC_HMAC_BLOCKSIZE) {
58	0	z = LTC_HMAC_BLOCKSIZE;
59	0	if ((err = hash_memory(hash, key, keylen, hmac->key, &z)) != CRYPT_OK) {
60	0	goto LBL_ERR;
61	0	}
62	0	keylen = hashsize;
63	8.71k	} else {
64	8.71k	XMEMCPY(hmac->key, key, (size_t)keylen);
65	8.71k	}
66
67	8.71k	if(keylen < LTC_HMAC_BLOCKSIZE) {
68	8.71k	zeromem((hmac->key) + keylen, (size_t)(LTC_HMAC_BLOCKSIZE - keylen));
69	8.71k	}
70
71		/* Create the initialization vector for step (3) */
72	566k	for(i=0; i < LTC_HMAC_BLOCKSIZE; i++) {
73	557k	buf[i] = hmac->key[i] ^ 0x36;
74	557k	}
75
76		/* Pre-pend that to the hash data */
77	8.71k	if ((err = hash_descriptor[hash].init(&hmac->md)) != CRYPT_OK) {
78	0	goto LBL_ERR;
79	0	}
80
81	8.71k	if ((err = hash_descriptor[hash].process(&hmac->md, buf, LTC_HMAC_BLOCKSIZE)) != CRYPT_OK) {
82	0	goto LBL_ERR;
83	0	}
84	8.71k	goto done;
85	8.71k	LBL_ERR:
86		/* free the key since we failed */
87	0	XFREE(hmac->key);
88	8.71k	done:
89		#ifdef LTC_CLEAN_STACK
90		zeromem(buf, LTC_HMAC_BLOCKSIZE);
91		#endif
92
93	8.71k	return err;
94	0	}
95
96		#endif
97
98		/* ref: $Format:%D$ */
99		/* git commit: $Format:%H$ */
100		/* commit time: $Format:%ai$ */

Coverage Report

Created: 2023-09-25 06:08