view libtomcrypt/src/hashes/helper/hash_memory.c @ 1861:2b3a8026a6ce

Add re-exec for server This allows ASLR to re-randomize the address space for every connection, preventing some vulnerabilities from being exploitable by repeated probing. Overhead (memory and time) is yet to be confirmed. At present this is only enabled on Linux. Other BSD platforms with fexecve() would probably also work though have not been tested.
author Matt Johnston <matt@ucc.asn.au>
date Sun, 30 Jan 2022 10:14:56 +0800
parents 6dba84798cd5
children
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/* 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"

#ifdef LTC_HASH_HELPERS
/**
  @file hash_memory.c
  Hash memory helper, Tom St Denis
*/

/**
  Hash a block of memory and store the digest.
  @param hash   The index of the hash you wish to use
  @param in     The data you wish to hash
  @param inlen  The length of the data to hash (octets)
  @param out    [out] Where to store the digest
  @param outlen [in/out] Max size and resulting size of the digest
  @return CRYPT_OK if successful
*/
int hash_memory(int hash, const unsigned char *in, unsigned long inlen, unsigned char *out, unsigned long *outlen)
{
    hash_state *md;
    int err;

    LTC_ARGCHK(in     != NULL);
    LTC_ARGCHK(out    != NULL);
    LTC_ARGCHK(outlen != NULL);

    if ((err = hash_is_valid(hash)) != CRYPT_OK) {
        return err;
    }

    if (*outlen < hash_descriptor[hash].hashsize) {
       *outlen = hash_descriptor[hash].hashsize;
       return CRYPT_BUFFER_OVERFLOW;
    }

    md = XMALLOC(sizeof(hash_state));
    if (md == NULL) {
       return CRYPT_MEM;
    }

    if ((err = hash_descriptor[hash].init(md)) != CRYPT_OK) {
       goto LBL_ERR;
    }
    if ((err = hash_descriptor[hash].process(md, in, inlen)) != CRYPT_OK) {
       goto LBL_ERR;
    }
    err = hash_descriptor[hash].done(md, out);
    *outlen = hash_descriptor[hash].hashsize;
LBL_ERR:
#ifdef LTC_CLEAN_STACK
    zeromem(md, sizeof(hash_state));
#endif
    XFREE(md);

    return err;
}
#endif /* #ifdef LTC_HASH_HELPERS */

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