postgres/contrib/pgcrypto/pgcrypto.c
2001-03-22 04:01:46 +00:00

139 lines
3.3 KiB
C

/*
* pgcrypto.c
* Cryptographic digests for PostgreSQL.
*
* Copyright (c) 2000 Marko Kreen
* All rights reserved.
*
* 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 above 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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.
*
* $Id: pgcrypto.c,v 1.7 2001/03/22 03:59:10 momjian Exp $
*/
#include "postgres.h"
#include "utils/builtins.h"
#include "pgcrypto.h"
/*
* NAMEDATALEN is used for hash names
*/
#if NAMEDATALEN < 16
#error "NAMEDATALEN < 16: too small"
#endif
/* exported functions */
Datum digest(PG_FUNCTION_ARGS);
Datum digest_exists(PG_FUNCTION_ARGS);
/* private stuff */
static pg_digest *
find_digest(pg_digest * hbuf, text *name, int silent);
/* SQL function: hash(text, text) returns text */
PG_FUNCTION_INFO_V1(digest);
Datum
digest(PG_FUNCTION_ARGS)
{
text *arg;
text *name;
uint len,
hlen;
pg_digest *h,
_hbuf;
text *res;
if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
PG_RETURN_NULL();
name = PG_GETARG_TEXT_P(1);
h = find_digest(&_hbuf, name, 0); /* will give error if fails */
hlen = h->length(h);
res = (text *) palloc(hlen + VARHDRSZ);
VARATT_SIZEP(res) = hlen + VARHDRSZ;
arg = PG_GETARG_TEXT_P(0);
len = VARSIZE(arg) - VARHDRSZ;
h->digest(h, VARDATA(arg), len, VARDATA(res));
PG_FREE_IF_COPY(arg, 0);
PG_FREE_IF_COPY(name, 1);
PG_RETURN_TEXT_P(res);
}
/* check if given hash exists */
PG_FUNCTION_INFO_V1(digest_exists);
Datum
digest_exists(PG_FUNCTION_ARGS)
{
text *name;
pg_digest _hbuf,
*res;
if (PG_ARGISNULL(0))
PG_RETURN_NULL();
name = PG_GETARG_TEXT_P(0);
res = find_digest(&_hbuf, name, 1);
PG_FREE_IF_COPY(name, 0);
if (res != NULL)
PG_RETURN_BOOL(true);
PG_RETURN_BOOL(false);
}
static pg_digest *
find_digest(pg_digest * hbuf, text *name, int silent)
{
pg_digest *p;
char buf[NAMEDATALEN];
uint len;
len = VARSIZE(name) - VARHDRSZ;
if (len >= NAMEDATALEN)
{
if (silent)
return NULL;
elog(ERROR, "Hash type does not exist (name too long)");
}
memcpy(buf, VARDATA(name), len);
buf[len] = 0;
p = pg_find_digest(hbuf, buf);
if (p == NULL && !silent)
elog(ERROR, "Hash type does not exist: '%s'", buf);
return p;
}