OpenBSD-4.6/kerberosV/src/lib/asn1/der_get.c
/*
* Copyright (c) 1997 - 2004 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
*/
#include "der_locl.h"
RCSID("$KTH: der_get.c,v 1.39 2005/05/29 14:23:00 lha Exp $");
#include <version.h>
/*
* All decoding functions take a pointer `p' to first position in
* which to read, from the left, `len' which means the maximum number
* of characters we are able to read, `ret' were the value will be
* returned and `size' where the number of used bytes is stored.
* Either 0 or an error code is returned.
*/
static int
der_get_unsigned (const unsigned char *p, size_t len,
unsigned *ret, size_t *size)
{
unsigned val = 0;
size_t oldlen = len;
while (len--)
val = val * 256 + *p++;
*ret = val;
if(size) *size = oldlen;
return 0;
}
int
der_get_int (const unsigned char *p, size_t len,
int *ret, size_t *size)
{
int val = 0;
size_t oldlen = len;
if (len > 0) {
val = (signed char)*p++;
while (--len)
val = val * 256 + *p++;
}
*ret = val;
if(size) *size = oldlen;
return 0;
}
int
der_get_boolean(const unsigned char *p, size_t len, int *data, size_t *size)
{
if(len < 1)
return ASN1_OVERRUN;
if(*p != 0)
*data = 1;
else
*data = 0;
*size = 1;
return 0;
}
int
der_get_length (const unsigned char *p, size_t len,
size_t *val, size_t *size)
{
size_t v;
if (len <= 0)
return ASN1_OVERRUN;
--len;
v = *p++;
if (v < 128) {
*val = v;
if(size) *size = 1;
} else {
int e;
size_t l;
unsigned tmp;
if(v == 0x80){
*val = ASN1_INDEFINITE;
if(size) *size = 1;
return 0;
}
v &= 0x7F;
if (len < v)
return ASN1_OVERRUN;
e = der_get_unsigned (p, v, &tmp, &l);
if(e) return e;
*val = tmp;
if(size) *size = l + 1;
}
return 0;
}
int
der_get_general_string (const unsigned char *p, size_t len,
heim_general_string *str, size_t *size)
{
char *s;
s = malloc (len + 1);
if (s == NULL)
return ENOMEM;
memcpy (s, p, len);
s[len] = '\0';
*str = s;
if(size) *size = len;
return 0;
}
int
der_get_octet_string (const unsigned char *p, size_t len,
heim_octet_string *data, size_t *size)
{
data->length = len;
data->data = malloc(len);
if (data->data == NULL && data->length != 0)
return ENOMEM;
memcpy (data->data, p, len);
if(size) *size = len;
return 0;
}
int
der_get_oid (const unsigned char *p, size_t len,
heim_oid *data, size_t *size)
{
int n;
size_t oldlen = len;
if (len < 1)
return ASN1_OVERRUN;
data->components = malloc((len + 1) * sizeof(*data->components));
if (data->components == NULL)
return ENOMEM;
data->components[0] = (*p) / 40;
data->components[1] = (*p) % 40;
--len;
++p;
for (n = 2; len > 0; ++n) {
unsigned u = 0;
do {
--len;
u = u * 128 + (*p++ % 128);
} while (len > 0 && p[-1] & 0x80);
data->components[n] = u;
}
if (len > 0 && p[-1] & 0x80) {
free_oid (data);
return ASN1_OVERRUN;
}
data->length = n;
if (size)
*size = oldlen;
return 0;
}
int
der_get_tag (const unsigned char *p, size_t len,
Der_class *class, Der_type *type,
int *tag, size_t *size)
{
if (len < 1)
return ASN1_OVERRUN;
*class = (Der_class)(((*p) >> 6) & 0x03);
*type = (Der_type)(((*p) >> 5) & 0x01);
*tag = (*p) & 0x1F;
if(size) *size = 1;
return 0;
}
int
der_match_tag (const unsigned char *p, size_t len,
Der_class class, Der_type type,
int tag, size_t *size)
{
size_t l;
Der_class thisclass;
Der_type thistype;
int thistag;
int e;
e = der_get_tag (p, len, &thisclass, &thistype, &thistag, &l);
if (e) return e;
if (class != thisclass || type != thistype)
return ASN1_BAD_ID;
if(tag > thistag)
return ASN1_MISPLACED_FIELD;
if(tag < thistag)
return ASN1_MISSING_FIELD;
if(size) *size = l;
return 0;
}
int
der_match_tag_and_length (const unsigned char *p, size_t len,
Der_class class, Der_type type, int tag,
size_t *length_ret, size_t *size)
{
size_t l, ret = 0;
int e;
e = der_match_tag (p, len, class, type, tag, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, length_ret, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_boolean (const unsigned char *p, size_t len,
int *num, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_Boolean, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (reallen > len)
return ASN1_OVERRUN;
e = der_get_boolean (p, reallen, num, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_integer (const unsigned char *p, size_t len,
int *num, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_Integer, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (reallen > len)
return ASN1_OVERRUN;
e = der_get_int (p, reallen, num, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_unsigned (const unsigned char *p, size_t len,
unsigned *num, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_Integer, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (reallen > len)
return ASN1_OVERRUN;
e = der_get_unsigned (p, reallen, num, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_enumerated (const unsigned char *p, size_t len,
unsigned *num, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_Enumerated, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (reallen > len)
return ASN1_OVERRUN;
e = der_get_int (p, reallen, num, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_general_string (const unsigned char *p, size_t len,
heim_general_string *str, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_GeneralString, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (len < reallen)
return ASN1_OVERRUN;
e = der_get_general_string (p, reallen, str, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_octet_string (const unsigned char *p, size_t len,
heim_octet_string *k, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_OctetString, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (len < reallen)
return ASN1_OVERRUN;
e = der_get_octet_string (p, reallen, k, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
int
decode_oid (const unsigned char *p, size_t len,
heim_oid *k, size_t *size)
{
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_OID, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (len < reallen)
return ASN1_OVERRUN;
e = der_get_oid (p, reallen, k, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if(size) *size = ret;
return 0;
}
static void
generalizedtime2time (const char *s, time_t *t)
{
struct tm tm;
memset(&tm, 0, sizeof(tm));
sscanf (s, "%04d%02d%02d%02d%02d%02dZ",
&tm.tm_year, &tm.tm_mon, &tm.tm_mday, &tm.tm_hour,
&tm.tm_min, &tm.tm_sec);
tm.tm_year -= 1900;
tm.tm_mon -= 1;
*t = timegm (&tm);
}
int
decode_generalized_time (const unsigned char *p, size_t len,
time_t *t, size_t *size)
{
heim_octet_string k;
char *times;
size_t ret = 0;
size_t l, reallen;
int e;
e = der_match_tag (p, len, ASN1_C_UNIV, PRIM, UT_GeneralizedTime, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
e = der_get_length (p, len, &reallen, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
if (len < reallen)
return ASN1_OVERRUN;
e = der_get_octet_string (p, reallen, &k, &l);
if (e) return e;
p += l;
len -= l;
ret += l;
times = realloc(k.data, k.length + 1);
if (times == NULL){
free(k.data);
return ENOMEM;
}
times[k.length] = 0;
generalizedtime2time (times, t);
free (times);
if(size) *size = ret;
return 0;
}
int
fix_dce(size_t reallen, size_t *len)
{
if(reallen == ASN1_INDEFINITE)
return 1;
if(*len < reallen)
return -1;
*len = reallen;
return 0;
}