Files
heimdal/lib/asn1/gen_locl.h
Nicolas Williams db7763ca7b asn1: X.681/682/683 magic handling of open types
Status:

 - And it works!

 - We have an extensive test based on decoding a rich EK certficate.

   This test exercises all of:

    - decoding
    - encoding with and without decoded open types
    - copying of decoded values with decoded open types
    - freeing of decoded values with decoded open types

   Valgrind finds no memory errors.

 - Added a manual page for the compiler.

 - rfc2459.asn1 now has all three primary PKIX types that we care about
   defined as in RFC5912, with IOS constraints and parameterization:

    - `Extension`       (embeds open type in an `OCTET STRING`)
    - `OtherName`       (embeds open type in an        `ANY`-like type)
    - `SingleAttribute` (embeds open type in an        `ANY`-like type)
    - `AttributeSet`    (embeds open type in a  `SET OF ANY`-like type)

   All of these use OIDs as the open type type ID field, but integer
   open type type ID fields are also supported (and needed, for
   Kerberos).

   That will cover every typed hole pattern in all our ASN.1 modules.

   With this we'll be able to automatically and recursively decode
   through all subject DN attributes even when the subject DN is a
   directoryName SAN, and subjectDirectoryAttributes, and all
   extensions, and all SANs, and all authorization-data elements, and
   PA-data, and...

   We're not really using `SingleAttribute` and `AttributeSet` yet
   because various changes are needed in `lib/hx509` for that.

 - `asn1_compile` builds and recognizes the subset of X.681/682/683 that
   we need for, and now use in, rfc2459.asn1.  It builds the necessary
   AST, generates the correct C types, and generates templating for
   object sets and open types!

 - See READMEs for details.

 - Codegen backend not tested; I won't make it implement automatic open
   type handling, but it should at least not crash by substituting
   `heim_any` for open types not embedded in `OCTET STRING`.

 - We're _really_ starting to have problems with the ITU-T ASN.1
   grammar and our version of it...

   Type names have to start with upper-case, value names with
   lower-case, but it's not enough to disambiguate.

   The fact the we've allowed value and type names to violate their
   respective start-with case rules is causing us trouble now that we're
   adding grammar from X.681/682/683, and we're going to have to undo
   that.

   In preparation for that I'm capitalizing the `heim_any` and
   `heim_any_set` types, and doing some additional cleanup, which
   requires changes to other parts of Heimdal (all in this same commit
   for now).

   Problems we have because of this:

    - We cannot IMPORT values into modules because we have no idea if a
      symbol being imported refers to a value or a type because the only
      clue we would have is the symbol's name, so we assume IMPORTed
      symbols are for types.

      This means we can't import OIDs, for example, which is super
      annoying.

      One thing we might be able to do here is mark imported symbols as
      being of an undetermined-but-not-undefined type, then coerce the
      symbol's type the first time it's used in a context where its type
      is inferred as type, value, object, object set, or class.  (Though
      since we don't generate C symbols for objects or classes, we won't
      be able to import them, especially since we need to know them at
      compile time and cannot defer their handling to link- or
      run-time.)

    - The `NULL` type name, and the `NULL` value name now cause two
      reduce/reduce conflicts via the `FieldSetting` production.

    - Various shift/reduce conflicts involving `NULL` values in
      non-top-level contexts (in constraints, for example).

 - Currently I have a bug where to disambiguate the grammar I have a
   CLASS_IDENTIFIER token that is all caps, while TYPE_IDENTIFIER must
   start with a capital but not be all caps, but this breaks Kerberos
   since all its types are all capitalized -- oof!

   To fix this I made it so class names have to be all caps and
   start with an underscore (ick).

TBD:

 - Check all the XXX comments and address them
 - Apply this treatment to Kerberos!  Automatic handling of authz-data
   sounds useful :)
 - Apply this treatment to PKCS#10 (CSRs) and other ASN.1 modules too.
 - Replace various bits of code in `lib/hx509/` with uses of this
   feature.
 - Add JER.
 - Enhance `hxtool` and `asn1_print`.

Getting there!
2021-02-28 18:13:08 -06:00

173 lines
5.8 KiB
C

/*
* Copyright (c) 1997-2005 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.
*/
/* $Id$ */
#ifndef __GEN_LOCL_H__
#define __GEN_LOCL_H__
#include <config.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <ctype.h>
#include <time.h>
#include <errno.h>
#include <err.h>
#include <roken.h>
#include <getarg.h>
#include "hash.h"
#include "symbol.h"
#include "asn1-common.h"
#include "der.h"
#include "der-private.h"
/*
* XXX We need to move all module state out of globals and into a struct that
* we pass around when parsing and compiling a module, and also that we keep on
* a linked list of parsed modules.
*
* This is needed to:
*
* - implement IMPORTS correctly, because we need to know the type of a symbol
* in order to emit an extern declaration of it
* - implement value parsing
* - implement an ASN.1 library that does value parsing
*
* Value parsing, in particular, would be fantastic. We could then have
* options in hxtool(1) to load arbitrary ASN.1 modules and then parse SAN
* values given in ASN.1 value syntax on the command-line or in files. Eat
* your heart out OpenSSL if we do this!
*
* As well we'll need a `-I' option to the compiler so it knows where to find
* modules to IMPORT FROM.
*/
typedef struct asn1_module {
/* Name of ASN.1 module file: */
const char *orig_filename;
/* Name of file to always include for common type definitions: */
const char *type_file_string;
/* Name of public header file for module: */
const char *header;
/* Name of private header file for module: */
const char *privheader;
/* Basename of module: */
const char *headerbase;
/* Open stdio file handles for output: */
FILE *privheaderfile;
FILE *headerfile;
FILE *oidsfile;
FILE *codefile;
FILE *logfile;
FILE *templatefile;
/* Module contents: */
struct sexport *exports;
struct import *imports;
Hashtab *htab; /* symbols */
/* Template state: */
struct templatehead *template;
struct tlisthead *tlistmaster;
/* CLI options and flags needed everywhere: */
getarg_strings preserve;
getarg_strings seq;
const char *enum_prefix;
unsigned int one_code_file:1;
unsigned int support_ber:1;
unsigned int parse_units_flag:1;
unsigned int prefix_enum:1; /* Should be a getarg_strings of bitrsting types to do this for */
unsigned int rfc1510_bitstring:1; /* Should be a getarg_strings of bitrsting types to do this for */
} *asn1_module;
void generate_type (const Symbol *);
void generate_type_header_forwards(const Symbol *);
void generate_constant (const Symbol *);
void generate_type_encode (const Symbol *);
void generate_type_decode (const Symbol *);
void generate_type_free (const Symbol *);
void generate_type_length (const Symbol *);
void generate_type_copy (const Symbol *);
void generate_type_seq (const Symbol *);
void generate_glue (const Type *, const char*);
const char *classname(Der_class);
const char *valuename(Der_class, int);
void gen_compare_defval(const char *, struct value *);
void gen_assign_defval(const char *, struct value *);
int objid_cmp(struct objid *, struct objid *);
void init_generate (const char *, const char *);
const char *get_filename (void);
void close_generate(void);
void add_import(const char *);
void add_export(const char *);
int is_export(const char *);
int yyparse(void);
int is_primitive_type(const Type *);
int preserve_type(const char *);
int seq_type(const char *);
void generate_header_of_codefile(const char *);
void close_codefile(void);
void get_open_type_defn_fields(const Type *, Member **, Member **, Field **,
Field **, int *);
void sort_object_set(IOSObjectSet *, Field *, IOSObject ***, size_t *);
int is_template_compat (const Symbol *);
void generate_template(const Symbol *);
void generate_template_type_forward(const char *);
void generate_template_objectset_forwards(const Symbol *);
void gen_template_import(const Symbol *);
extern FILE *privheaderfile, *headerfile, *codefile, *logfile, *templatefile;
extern const char *fuzzer_string;
extern int support_ber;
extern int template_flag;
extern int rfc1510_bitstring;
extern int one_code_file;
extern int original_order;
extern int parse_units_flag;
extern char *type_file_string;
extern int error_flag;
#endif /* __GEN_LOCL_H__ */