debmon/openssl1.0
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
upstream
openssl1.0/crypto/lhash/lhash.c
Mario Fetka 33f8b6874c Imported Upstream version 1.0.2s
2019-08-09 10:00:55 +02:00

478 lines
13 KiB
C
Raw Permalink Blame History

/* crypto/lhash/lhash.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/*-
* Code for dynamic hash table routines
* Author - Eric Young v 2.0
*
* 2.2 eay - added #include "crypto.h" so the memory leak checking code is
* present. eay 18-Jun-98
*
* 2.1 eay - Added an 'error in last operation' flag. eay 6-May-98
*
* 2.0 eay - Fixed a bug that occurred when using lh_delete
* from inside lh_doall(). As entries were deleted,
* the 'table' was 'contract()ed', making some entries
* jump from the end of the table to the start, there by
* skipping the lh_doall() processing. eay - 4/12/95
*
* 1.9 eay - Fixed a memory leak in lh_free, the LHASH_NODEs
* were not being free()ed. 21/11/95
*
* 1.8 eay - Put the stats routines into a separate file, lh_stats.c
* 19/09/95
*
* 1.7 eay - Removed the fputs() for realloc failures - the code
* should silently tolerate them. I have also fixed things
* lint complained about 04/05/95
*
* 1.6 eay - Fixed an invalid pointers in contract/expand 27/07/92
*
* 1.5 eay - Fixed a misuse of realloc in expand 02/03/1992
*
* 1.4 eay - Fixed lh_doall so the function can call lh_delete 28/05/91
*
* 1.3 eay - Fixed a few lint problems 19/3/1991
*
* 1.2 eay - Fixed lh_doall problem 13/3/1991
*
* 1.1 eay - Added lh_doall
*
* 1.0 eay - First version
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <openssl/crypto.h>
#include <openssl/lhash.h>
/*
* A hashing implementation that appears to be based on the linear hashing
* alogrithm:
* https://en.wikipedia.org/wiki/Linear_hashing
*
* Litwin, Witold (1980), "Linear hashing: A new tool for file and table
* addressing", Proc. 6th Conference on Very Large Databases: 212-223
* http://hackthology.com/pdfs/Litwin-1980-Linear_Hashing.pdf
*
* From the wikipedia article "Linear hashing is used in the BDB Berkeley
* database system, which in turn is used by many software systems such as
* OpenLDAP, using a C implementation derived from the CACM article and first
* published on the Usenet in 1988 by Esmond Pitt."
*
* The CACM paper is available here:
* https://pdfs.semanticscholar.org/ff4d/1c5deca6269cc316bfd952172284dbf610ee.pdf
*/
const char lh_version[] = "lhash" OPENSSL_VERSION_PTEXT;
#undef MIN_NODES
#define MIN_NODES 16
#define UP_LOAD (2*LH_LOAD_MULT) /* load times 256 (default 2) */
#define DOWN_LOAD (LH_LOAD_MULT) /* load times 256 (default 1) */
static int expand(_LHASH *lh);
static void contract(_LHASH *lh);
static LHASH_NODE **getrn(_LHASH *lh, const void *data, unsigned long *rhash);
_LHASH *lh_new(LHASH_HASH_FN_TYPE h, LHASH_COMP_FN_TYPE c)
{
_LHASH *ret;
int i;
if ((ret = OPENSSL_malloc(sizeof(_LHASH))) == NULL)
goto err0;
if ((ret->b = OPENSSL_malloc(sizeof(LHASH_NODE *) * MIN_NODES)) == NULL)
goto err1;
for (i = 0; i < MIN_NODES; i++)
ret->b[i] = NULL;
ret->comp = ((c == NULL) ? (LHASH_COMP_FN_TYPE)strcmp : c);
ret->hash = ((h == NULL) ? (LHASH_HASH_FN_TYPE)lh_strhash : h);
ret->num_nodes = MIN_NODES / 2;
ret->num_alloc_nodes = MIN_NODES;
ret->p = 0;
ret->pmax = MIN_NODES / 2;
ret->up_load = UP_LOAD;
ret->down_load = DOWN_LOAD;
ret->num_items = 0;
ret->num_expands = 0;
ret->num_expand_reallocs = 0;
ret->num_contracts = 0;
ret->num_contract_reallocs = 0;
ret->num_hash_calls = 0;
ret->num_comp_calls = 0;
ret->num_insert = 0;
ret->num_replace = 0;
ret->num_delete = 0;
ret->num_no_delete = 0;
ret->num_retrieve = 0;
ret->num_retrieve_miss = 0;
ret->num_hash_comps = 0;
ret->error = 0;
return (ret);
err1:
OPENSSL_free(ret);
err0:
return (NULL);
}
void lh_free(_LHASH *lh)
{
unsigned int i;
LHASH_NODE *n, *nn;
if (lh == NULL)
return;
for (i = 0; i < lh->num_nodes; i++) {
n = lh->b[i];
while (n != NULL) {
nn = n->next;
OPENSSL_free(n);
n = nn;
}
}
OPENSSL_free(lh->b);
OPENSSL_free(lh);
}
void *lh_insert(_LHASH *lh, void *data)
{
unsigned long hash;
LHASH_NODE *nn, **rn;
void *ret;
lh->error = 0;
if (lh->up_load <= (lh->num_items * LH_LOAD_MULT / lh->num_nodes)
&& !expand(lh))
return NULL;
rn = getrn(lh, data, &hash);
if (*rn == NULL) {
if ((nn = (LHASH_NODE *)OPENSSL_malloc(sizeof(LHASH_NODE))) == NULL) {
lh->error++;
return (NULL);
}
nn->data = data;
nn->next = NULL;
#ifndef OPENSSL_NO_HASH_COMP
nn->hash = hash;
#endif
*rn = nn;
ret = NULL;
lh->num_insert++;
lh->num_items++;
} else { /* replace same key */
ret = (*rn)->data;
(*rn)->data = data;
lh->num_replace++;
}
return (ret);
}
void *lh_delete(_LHASH *lh, const void *data)
{
unsigned long hash;
LHASH_NODE *nn, **rn;
void *ret;
lh->error = 0;
rn = getrn(lh, data, &hash);
if (*rn == NULL) {
lh->num_no_delete++;
return (NULL);
} else {
nn = *rn;
*rn = nn->next;
ret = nn->data;
OPENSSL_free(nn);
lh->num_delete++;
}
lh->num_items--;
if ((lh->num_nodes > MIN_NODES) &&
(lh->down_load >= (lh->num_items * LH_LOAD_MULT / lh->num_nodes)))
contract(lh);
return (ret);
}
void *lh_retrieve(_LHASH *lh, const void *data)
{
unsigned long hash;
LHASH_NODE **rn;
void *ret;
lh->error = 0;
rn = getrn(lh, data, &hash);
if (*rn == NULL) {
lh->num_retrieve_miss++;
return (NULL);
} else {
ret = (*rn)->data;
lh->num_retrieve++;
}
return (ret);
}
static void doall_util_fn(_LHASH *lh, int use_arg, LHASH_DOALL_FN_TYPE func,
LHASH_DOALL_ARG_FN_TYPE func_arg, void *arg)
{
int i;
LHASH_NODE *a, *n;
if (lh == NULL)
return;
/*
* reverse the order so we search from 'top to bottom' We were having
* memory leaks otherwise
*/
for (i = lh->num_nodes - 1; i >= 0; i--) {
a = lh->b[i];
while (a != NULL) {
/*
* 28/05/91 - eay - n added so items can be deleted via lh_doall
*/
/*
* 22/05/08 - ben - eh? since a is not passed, this should not be
* needed
*/
n = a->next;
if (use_arg)
func_arg(a->data, arg);
else
func(a->data);
a = n;
}
}
}
void lh_doall(_LHASH *lh, LHASH_DOALL_FN_TYPE func)
{
doall_util_fn(lh, 0, func, (LHASH_DOALL_ARG_FN_TYPE)0, NULL);
}
void lh_doall_arg(_LHASH *lh, LHASH_DOALL_ARG_FN_TYPE func, void *arg)
{
doall_util_fn(lh, 1, (LHASH_DOALL_FN_TYPE)0, func, arg);
}
static int expand(_LHASH *lh)
{
LHASH_NODE **n, **n1, **n2, *np;
unsigned int p, pmax, nni, j;
unsigned long hash;
nni = lh->num_alloc_nodes;
p = lh->p;
pmax = lh->pmax;
if (p + 1 >= pmax) {
j = nni * 2;
n = OPENSSL_realloc(lh->b, (int)(sizeof(LHASH_NODE *) * j));
if (n == NULL) {
lh->error++;
return 0;
}
lh->b = n;
memset(n + nni, 0, sizeof(*n) * (j - nni));
lh->pmax = nni;
lh->num_alloc_nodes = j;
lh->num_expand_reallocs++;
lh->p = 0;
} else {
lh->p++;
}
lh->num_nodes++;
lh->num_expands++;
n1 = &(lh->b[p]);
n2 = &(lh->b[p + pmax]);
*n2 = NULL;
for (np = *n1; np != NULL;) {
#ifndef OPENSSL_NO_HASH_COMP
hash = np->hash;
#else
hash = lh->hash(np->data);
lh->num_hash_calls++;
#endif
if ((hash % nni) != p) { /* move it */
*n1 = (*n1)->next;
np->next = *n2;
*n2 = np;
} else
n1 = &((*n1)->next);
np = *n1;
}
return 1;
}
static void contract(_LHASH *lh)
{
LHASH_NODE **n, *n1, *np;
np = lh->b[lh->p + lh->pmax - 1];
lh->b[lh->p + lh->pmax - 1] = NULL; /* 24/07-92 - eay - weird but :-( */
if (lh->p == 0) {
n = (LHASH_NODE **)OPENSSL_realloc(lh->b,
(unsigned int)(sizeof(LHASH_NODE *)
* lh->pmax));
if (n == NULL) {
/* fputs("realloc error in lhash",stderr); */
lh->error++;
return;
}
lh->num_contract_reallocs++;
lh->num_alloc_nodes /= 2;
lh->pmax /= 2;
lh->p = lh->pmax - 1;
lh->b = n;
} else
lh->p--;
lh->num_nodes--;
lh->num_contracts++;
n1 = lh->b[(int)lh->p];
if (n1 == NULL)
lh->b[(int)lh->p] = np;
else {
while (n1->next != NULL)
n1 = n1->next;
n1->next = np;
}
}
static LHASH_NODE **getrn(_LHASH *lh, const void *data, unsigned long *rhash)
{
LHASH_NODE **ret, *n1;
unsigned long hash, nn;
LHASH_COMP_FN_TYPE cf;
hash = (*(lh->hash)) (data);
lh->num_hash_calls++;
*rhash = hash;
nn = hash % lh->pmax;
if (nn < lh->p)
nn = hash % lh->num_alloc_nodes;
cf = lh->comp;
ret = &(lh->b[(int)nn]);
for (n1 = *ret; n1 != NULL; n1 = n1->next) {
#ifndef OPENSSL_NO_HASH_COMP
lh->num_hash_comps++;
if (n1->hash != hash) {
ret = &(n1->next);
continue;
}
#endif
lh->num_comp_calls++;
if (cf(n1->data, data) == 0)
break;
ret = &(n1->next);
}
return (ret);
}
/*
* The following hash seems to work very well on normal text strings no
* collisions on /usr/dict/words and it distributes on %2^n quite well, not
* as good as MD5, but still good.
*/
unsigned long lh_strhash(const char *c)
{
unsigned long ret = 0;
long n;
unsigned long v;
int r;
if ((c == NULL) || (*c == '\0'))
return (ret);
/*-
unsigned char b[16];
MD5(c,strlen(c),b);
return(b[0]|(b[1]<<8)|(b[2]<<16)|(b[3]<<24));
*/
n = 0x100;
while (*c) {
v = n | (*c);
n += 0x100;
r = (int)((v >> 2) ^ v) & 0x0f;
ret = (ret << r) | (ret >> (32 - r));
ret &= 0xFFFFFFFFL;
ret ^= v * v;
c++;
}
return ((ret >> 16) ^ ret);
}
unsigned long lh_num_items(const _LHASH *lh)
{
return lh ? lh->num_items : 0;
}
Reference in New Issue View Git Blame Copy Permalink