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 * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
10 */
11 #include "tomcrypt.h"
12 #include <stdarg.h>
13 /**
14 @file hash_memory_multi.c
15 Hash (multiple buffers) memory helper, Tom St Denis
16 */
17
18 /**
19 Hash multiple (non-adjacent) blocks of memory at once.
20 @param hash The index of the hash you wish to use
21 @param out [out] Where to store the digest
22 @param outlen [in/out] Max size and resulting size of the digest
23 @param in The data you wish to hash
24 @param inlen The length of the data to hash (octets)
25 @param ... tuples of (data,len) pairs to hash, terminated with a (NULL,x) (x=don't care)
26 @return CRYPT_OK if successful
27 */
hash_memory_multi(int hash,unsigned char * out,unsigned long * outlen,const unsigned char * in,unsigned long inlen,...)28 int hash_memory_multi(int hash, unsigned char *out, unsigned long *outlen,
29 const unsigned char *in, unsigned long inlen, ...)
30 {
31 hash_state *md;
32 int err;
33 va_list args;
34 const unsigned char *curptr;
35 unsigned long curlen;
36
37 LTC_ARGCHK(in != NULL);
38 LTC_ARGCHK(out != NULL);
39 LTC_ARGCHK(outlen != NULL);
40
41 if ((err = hash_is_valid(hash)) != CRYPT_OK) {
42 return err;
43 }
44
45 if (*outlen < hash_descriptor[hash].hashsize) {
46 *outlen = hash_descriptor[hash].hashsize;
47 return CRYPT_BUFFER_OVERFLOW;
48 }
49
50 md = XMALLOC(sizeof(hash_state));
51 if (md == NULL) {
52 return CRYPT_MEM;
53 }
54
55 if ((err = hash_descriptor[hash].init(md)) != CRYPT_OK) {
56 goto LBL_ERR;
57 }
58
59 va_start(args, inlen);
60 curptr = in;
61 curlen = inlen;
62 for (;;) {
63 /* process buf */
64 if ((err = hash_descriptor[hash].process(md, curptr, curlen)) != CRYPT_OK) {
65 goto LBL_ERR;
66 }
67 /* step to next */
68 curptr = va_arg(args, const unsigned char*);
69 if (curptr == NULL) {
70 break;
71 }
72 curlen = va_arg(args, unsigned long);
73 }
74 err = hash_descriptor[hash].done(md, out);
75 *outlen = hash_descriptor[hash].hashsize;
76 LBL_ERR:
77 #ifdef LTC_CLEAN_STACK
78 zeromem(md, sizeof(hash_state));
79 #endif
80 XFREE(md);
81 va_end(args);
82 return err;
83 }
84
85 /* $Source: /cvs/libtom/libtomcrypt/src/hashes/helper/hash_memory_multi.c,v $ */
86 /* $Revision: 1.5 $ */
87 /* $Date: 2006/06/16 21:53:41 $ */
88