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 (at) 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 */ 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