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
13 /**
14 @file hash_filehandle.c
15 Hash open files, Tom St Denis
16 */
17
18 /**
19 Hash data from an open file handle.
20 @param hash The index of the hash you want to use
21 @param in The FILE* handle of the file you want to hash
22 @param out [out] The destination of the digest
23 @param outlen [in/out] The max size and resulting size of the digest
24 @result CRYPT_OK if successful
25 */
hash_filehandle(int hash,FILE * in,unsigned char * out,unsigned long * outlen)26 int hash_filehandle(int hash, FILE *in, unsigned char *out, unsigned long *outlen)
27 {
28 #ifdef LTC_NO_FILE
29 return CRYPT_NOP;
30 #else
31 hash_state md;
32 unsigned char buf[512];
33 size_t x;
34 int err;
35
36 LTC_ARGCHK(out != NULL);
37 LTC_ARGCHK(outlen != NULL);
38 LTC_ARGCHK(in != NULL);
39
40 if ((err = hash_is_valid(hash)) != CRYPT_OK) {
41 return err;
42 }
43
44 if (*outlen < hash_descriptor[hash].hashsize) {
45 *outlen = hash_descriptor[hash].hashsize;
46 return CRYPT_BUFFER_OVERFLOW;
47 }
48 if ((err = hash_descriptor[hash].init(&md)) != CRYPT_OK) {
49 return err;
50 }
51
52 *outlen = hash_descriptor[hash].hashsize;
53 do {
54 x = fread(buf, 1, sizeof(buf), in);
55 if ((err = hash_descriptor[hash].process(&md, buf, x)) != CRYPT_OK) {
56 return err;
57 }
58 } while (x == sizeof(buf));
59 err = hash_descriptor[hash].done(&md, out);
60
61 #ifdef LTC_CLEAN_STACK
62 zeromem(buf, sizeof(buf));
63 #endif
64 return err;
65 #endif
66 }
67
68
69 /* $Source: /cvs/libtom/libtomcrypt/src/hashes/helper/hash_filehandle.c,v $ */
70 /* $Revision: 1.5 $ */
71 /* $Date: 2006/06/16 21:53:41 $ */
72