xref: /freebsd/crypto/heimdal/lib/asn1/gen_encode.c (revision 5e9cd1ae3e10592ed70e7575551cba1bbab04d84)

/*
 * Copyright (c) 1997 - 2000 Kungliga Tekniska H�gskolan
 * (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 "gen_locl.h"

RCSID("$Id: gen_encode.c,v 1.11 2000/06/19 15:19:08 joda Exp $");

static void
encode_primitive (const char *typename, const char *name)
{
    fprintf (codefile,
	     "e = encode_%s(p, len, %s, &l);\n"
	     "BACK;\n",
	     typename,
	     name);
}

static void
encode_type (const char *name, const Type *t)
{
    switch (t->type) {
    case TType:
#if 0
	encode_type (name, t->symbol->type);
#endif
	fprintf (codefile,
		 "e = encode_%s(p, len, %s, &l);\n"
		 "BACK;\n",
		 t->symbol->gen_name, name);
	break;
    case TInteger:
	if(t->members == NULL)
	    encode_primitive ("integer", name);
	else {
	    char *s;
	    asprintf(&s, "(const int*)%s", name);
	    if(s == NULL)
		errx(1, "out of memory");
	    encode_primitive ("integer", s);
	    free(s);
	}
	break;
    case TUInteger:
	encode_primitive ("unsigned", name);
	break;
    case TOctetString:
	encode_primitive ("octet_string", name);
	break;
    case TBitString: {
	Member *m;
	int pos;
	int rest;
	int tag = -1;

	if (t->members == NULL)
	    break;

	fprintf (codefile, "{\n"
		 "unsigned char c = 0;\n");
	pos = t->members->prev->val;
	/* fix for buggy MIT (and OSF?) code */
	if (pos > 31)
	    abort ();
	/*
	 * It seems that if we do not always set pos to 31 here, the MIT
	 * code will do the wrong thing.
	 *
	 * I hate ASN.1 (and DER), but I hate it even more when everybody
	 * has to screw it up differently.
	 */
	pos = 31;
	rest = 7 - (pos % 8);

	for (m = t->members->prev; m && tag != m->val; m = m->prev) {
	    while (m->val / 8 < pos / 8) {
		fprintf (codefile,
			 "*p-- = c; len--; ret++;\n"
			 "c = 0;\n");
		pos -= 8;
	    }
	    fprintf (codefile,
		     "if(%s->%s) c |= 1<<%d;\n", name, m->gen_name,
		     7 - m->val % 8);

	    if (tag == -1)
		tag = m->val;
	}

	fprintf (codefile,
		 "*p-- = c;\n"
		 "*p-- = %d;\n"
		 "len -= 2;\n"
		 "ret += 2;\n"
		 "}\n\n"
		 "e = der_put_length_and_tag (p, len, ret, UNIV, PRIM,"
		 "UT_BitString, &l);\n"
		 "BACK;\n",
		 rest);
	break;
    }
    case TSequence: {
	Member *m;
	int tag = -1;

	if (t->members == NULL)
	    break;

	for (m = t->members->prev; m && tag != m->val; m = m->prev) {
	    char *s;

	    asprintf (&s, "%s(%s)->%s", m->optional ? "" : "&", name, m->gen_name);
	    if (m->optional)
		fprintf (codefile,
			 "if(%s)\n",
			 s);
#if 1
	    fprintf (codefile, "{\n"
		     "int oldret = ret;\n"
		     "ret = 0;\n");
#endif
	    encode_type (s, m->type);
	    fprintf (codefile,
		     "e = der_put_length_and_tag (p, len, ret, CONTEXT, CONS, "
		     "%d, &l);\n"
		     "BACK;\n",
		     m->val);
#if 1
	    fprintf (codefile,
		     "ret += oldret;\n"
		     "}\n");
#endif
	    if (tag == -1)
		tag = m->val;
	    free (s);
	}
	fprintf (codefile,
		 "e = der_put_length_and_tag (p, len, ret, UNIV, CONS, UT_Sequence, &l);\n"
		 "BACK;\n");
	break;
    }
    case TSequenceOf: {
	char *n;

	fprintf (codefile,
		 "for(i = (%s)->len - 1; i >= 0; --i) {\n"
#if 1
		 "int oldret = ret;\n"
		 "ret = 0;\n",
#else
		 ,
#endif
		 name);
	asprintf (&n, "&(%s)->val[i]", name);
	encode_type (n, t->subtype);
	fprintf (codefile,
#if 1
		 "ret += oldret;\n"
#endif
		 "}\n"
		 "e = der_put_length_and_tag (p, len, ret, UNIV, CONS, UT_Sequence, &l);\n"
		 "BACK;\n");
	free (n);
	break;
    }
    case TGeneralizedTime:
	encode_primitive ("generalized_time", name);
	break;
    case TGeneralString:
	encode_primitive ("general_string", name);
	break;
    case TApplication:
	encode_type (name, t->subtype);
	fprintf (codefile,
		 "e = der_put_length_and_tag (p, len, ret, APPL, CONS, %d, &l);\n"
		 "BACK;\n",
		 t->application);
	break;
    default:
	abort ();
    }
}

void
generate_type_encode (const Symbol *s)
{
  fprintf (headerfile,
	   "int    "
	   "encode_%s(unsigned char *, size_t, const %s *, size_t *);\n",
	   s->gen_name, s->gen_name);

  fprintf (codefile, "#define BACK if (e) return e; p -= l; len -= l; ret += l\n\n");


  fprintf (codefile, "int\n"
	   "encode_%s(unsigned char *p, size_t len,"
	   " const %s *data, size_t *size)\n"
	   "{\n",
	   s->gen_name, s->gen_name);

  switch (s->type->type) {
  case TInteger:
  case TUInteger:
  case TOctetString:
  case TGeneralizedTime:
  case TGeneralString:
  case TBitString:
  case TSequence:
  case TSequenceOf:
  case TApplication:
  case TType:
    fprintf (codefile,
	     "size_t ret = 0;\n"
	     "size_t l;\n"
	     "int i, e;\n\n");
    fprintf(codefile, "i = 0;\n"); /* hack to avoid `unused variable' */

      encode_type("data", s->type);

    fprintf (codefile, "*size = ret;\n"
	     "return 0;\n");
    break;
  default:
    abort ();
  }
  fprintf (codefile, "}\n\n");
}