openssl/crypto/asn1/tasn_utl.c

254 lines
6.6 KiB
C

/*
* Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stddef.h>
#include <string.h>
#include "internal/cryptlib.h"
#include "internal/refcount.h"
#include <openssl/asn1.h>
#include <openssl/asn1t.h>
#include <openssl/objects.h>
#include <openssl/err.h>
#include "asn1_local.h"
/* Utility functions for manipulating fields and offsets */
/* Add 'offset' to 'addr' */
#define offset2ptr(addr, offset) (void *)(((char *) addr) + offset)
/*
* Given an ASN1_ITEM CHOICE type return the selector value
*/
int asn1_get_choice_selector(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
int *sel = offset2ptr(*pval, it->utype);
return *sel;
}
/*
* Given an ASN1_ITEM CHOICE type set the selector value, return old value.
*/
int asn1_set_choice_selector(ASN1_VALUE **pval, int value,
const ASN1_ITEM *it)
{
int *sel, ret;
sel = offset2ptr(*pval, it->utype);
ret = *sel;
*sel = value;
return ret;
}
/*
* Do atomic reference counting. The value 'op' decides what to do.
* If it is +1 then the count is incremented.
* If |op| is 0, lock is initialised and count is set to 1.
* If |op| is -1, count is decremented and the return value is the current
* reference count or 0 if no reference count is active.
* It returns -1 on initialisation error.
* Used by ASN1_SEQUENCE construct of X509, X509_REQ, X509_CRL objects
*/
int asn1_do_lock(ASN1_VALUE **pval, int op, const ASN1_ITEM *it)
{
const ASN1_AUX *aux;
CRYPTO_REF_COUNT *lck;
CRYPTO_RWLOCK **lock;
int ret = -1;
if ((it->itype != ASN1_ITYPE_SEQUENCE)
&& (it->itype != ASN1_ITYPE_NDEF_SEQUENCE))
return 0;
aux = it->funcs;
if (!aux || !(aux->flags & ASN1_AFLG_REFCOUNT))
return 0;
lck = offset2ptr(*pval, aux->ref_offset);
lock = offset2ptr(*pval, aux->ref_lock);
switch (op) {
case 0:
*lck = ret = 1;
*lock = CRYPTO_THREAD_lock_new();
if (*lock == NULL) {
ASN1err(ASN1_F_ASN1_DO_LOCK, ERR_R_MALLOC_FAILURE);
return -1;
}
break;
case 1:
if (!CRYPTO_UP_REF(lck, &ret, *lock))
return -1;
break;
case -1:
if (!CRYPTO_DOWN_REF(lck, &ret, *lock))
return -1; /* failed */
#ifdef REF_PRINT
fprintf(stderr, "%p:%4d:%s\n", it, ret, it->sname);
#endif
REF_ASSERT_ISNT(ret < 0);
if (ret == 0) {
CRYPTO_THREAD_lock_free(*lock);
*lock = NULL;
}
break;
}
return ret;
}
static ASN1_ENCODING *asn1_get_enc_ptr(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
const ASN1_AUX *aux;
if (!pval || !*pval)
return NULL;
aux = it->funcs;
if (!aux || !(aux->flags & ASN1_AFLG_ENCODING))
return NULL;
return offset2ptr(*pval, aux->enc_offset);
}
void asn1_enc_init(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
ASN1_ENCODING *enc;
enc = asn1_get_enc_ptr(pval, it);
if (enc) {
enc->enc = NULL;
enc->len = 0;
enc->modified = 1;
}
}
void asn1_enc_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
ASN1_ENCODING *enc;
enc = asn1_get_enc_ptr(pval, it);
if (enc) {
OPENSSL_free(enc->enc);
enc->enc = NULL;
enc->len = 0;
enc->modified = 1;
}
}
int asn1_enc_save(ASN1_VALUE **pval, const unsigned char *in, int inlen,
const ASN1_ITEM *it)
{
ASN1_ENCODING *enc;
enc = asn1_get_enc_ptr(pval, it);
if (!enc)
return 1;
OPENSSL_free(enc->enc);
if ((enc->enc = OPENSSL_malloc(inlen)) == NULL) {
ASN1err(ASN1_F_ASN1_ENC_SAVE, ERR_R_MALLOC_FAILURE);
return 0;
}
memcpy(enc->enc, in, inlen);
enc->len = inlen;
enc->modified = 0;
return 1;
}
int asn1_enc_restore(int *len, unsigned char **out, ASN1_VALUE **pval,
const ASN1_ITEM *it)
{
ASN1_ENCODING *enc;
enc = asn1_get_enc_ptr(pval, it);
if (!enc || enc->modified)
return 0;
if (out) {
memcpy(*out, enc->enc, enc->len);
*out += enc->len;
}
if (len)
*len = enc->len;
return 1;
}
/* Given an ASN1_TEMPLATE get a pointer to a field */
ASN1_VALUE **asn1_get_field_ptr(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt)
{
ASN1_VALUE **pvaltmp;
pvaltmp = offset2ptr(*pval, tt->offset);
/*
* NOTE for BOOLEAN types the field is just a plain int so we can't
* return int **, so settle for (int *).
*/
return pvaltmp;
}
/*
* Handle ANY DEFINED BY template, find the selector, look up the relevant
* ASN1_TEMPLATE in the table and return it.
*/
const ASN1_TEMPLATE *asn1_do_adb(ASN1_VALUE **pval, const ASN1_TEMPLATE *tt,
int nullerr)
{
const ASN1_ADB *adb;
const ASN1_ADB_TABLE *atbl;
long selector;
ASN1_VALUE **sfld;
int i;
if (!(tt->flags & ASN1_TFLG_ADB_MASK))
return tt;
/* Else ANY DEFINED BY ... get the table */
adb = ASN1_ADB_ptr(tt->item);
/* Get the selector field */
sfld = offset2ptr(*pval, adb->offset);
/* Check if NULL */
if (*sfld == NULL) {
if (!adb->null_tt)
goto err;
return adb->null_tt;
}
/*
* Convert type to a long: NB: don't check for NID_undef here because it
* might be a legitimate value in the table
*/
if (tt->flags & ASN1_TFLG_ADB_OID)
selector = OBJ_obj2nid((ASN1_OBJECT *)*sfld);
else
selector = ASN1_INTEGER_get((ASN1_INTEGER *)*sfld);
/* Let application callback translate value */
if (adb->adb_cb != NULL && adb->adb_cb(&selector) == 0) {
ASN1err(ASN1_F_ASN1_DO_ADB, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE);
return NULL;
}
/*
* Try to find matching entry in table Maybe should check application
* types first to allow application override? Might also be useful to
* have a flag which indicates table is sorted and we can do a binary
* search. For now stick to a linear search.
*/
for (atbl = adb->tbl, i = 0; i < adb->tblcount; i++, atbl++)
if (atbl->value == selector)
return &atbl->tt;
/* FIXME: need to search application table too */
/* No match, return default type */
if (!adb->default_tt)
goto err;
return adb->default_tt;
err:
/* FIXME: should log the value or OID of unsupported type */
if (nullerr)
ASN1err(ASN1_F_ASN1_DO_ADB, ASN1_R_UNSUPPORTED_ANY_DEFINED_BY_TYPE);
return NULL;
}