Gather up another utility.

[u/mdw/catacomb] / cc.h

/* -*-c-*-
 *
 * $Id$
 *
 * Catcrypt common stuff
 *
 * (c) 2004 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 * 
 * Catacomb is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

#ifndef CATACOMB_CC_H
#define CATACOMB_CC_H

#ifdef __cplusplus
  extern "C" {
#endif

/*----- Header files ------------------------------------------------------*/

#include <stdio.h>
#include <string.h>

#include <mLib/dstr.h>

#include "key.h"
#include "gcipher.h"
#include "ghash.h"
#include "gmac.h"

/*----- Data structures ---------------------------------------------------*/

/* --- Key encapsulation --- */

typedef struct kem {
  const struct kemops *ops;
  key_packdef *kp;
  void *kd;
  const gchash *h;
  const gccipher *c, *cx;
  const gcmac *m;
} kem;

typedef struct kemops {
  const key_fetchdef *kf;		/* Key fetching structure */
  size_t kdsz;				/* Size of the key-data structure */
  kem *(*init)(key */*k*/, void */*kd*/);
  int (*doit)(kem */*k*/, dstr */*d*/, ghash */*h*/);
  const char *(*check)(kem */*k*/);
  void (*destroy)(kem */*k*/);
} kemops;

struct kemtab {
  const char *name;
  const kemops *encops;
  const kemops *decops;
};

extern const struct kemtab kemtab[];

/* --- Signing --- */

typedef struct sig {
  const struct sigops *ops;
  key_packdef *kp;
  void *kd;
  ghash *h;
} sig;

typedef struct sigops {
  const key_fetchdef *kf;		/* Key fetching structure */
  size_t kdsz;				/* Size of the key-data structure */
  sig *(*init)(key */*k*/, void */*kd*/, const gchash */*hc*/);
  int (*doit)(sig */*s*/, dstr */*d*/);
  const char *(*check)(sig */*s*/);
  void (*destroy)(sig */*s*/);
} sigops;

struct sigtab {
  const char *name;
  const sigops *signops;
  const sigops *verifyops;
  const gchash *ch;
};
    
extern const struct sigtab sigtab[];

/* --- Data encoding --- */

typedef struct enc {
  const struct encops *ops;
  FILE *fp;
} enc;

typedef struct encops {
  const char *name;
  const char *rmode, *wmode;
  enc *(*initenc)(FILE */*fp*/, const char */*msg*/);
  enc *(*initdec)(FILE */*fp*/, const char */*msg*/);
  int (*read)(enc */*e*/, void */*p*/, size_t /*sz*/);
  int (*write)(enc */*e*/, const void */*p*/, size_t /*sz*/);
  int (*encdone)(enc */*e*/);
  int (*decdone)(enc */*e*/);
  void (*destroy)(enc */*e*/);
} encops;

extern const encops enctab[];

/*----- Functions provided ------------------------------------------------*/

/* --- @getkem@ --- *
 *
 * Arguments:	@key *k@ = the key to load
 *		@const char *app@ = application name
 *		@int wantpriv@ = nonzero if we want to decrypt
 *
 * Returns:	A key-encapsulating thing.
 *
 * Use:		Loads a key.
 */

extern kem *getkem(key */*k*/, const char */*app*/, int /*wantpriv*/);

/* --- @setupkem@ --- *
 *
 * Arguments:	@kem *k@ = key-encapsulation thing
 *		@dstr *d@ = key-encapsulation data
 *		@gcipher **cx@ = key-expansion function (for IVs)
 *		@gcipher **c@ = where to put initialized encryption scheme
 *		@gmac **m@ = where to put initialized MAC
 *
 * Returns:	Zero for success, nonzero on faliure.
 *
 * Use:		Initializes all the various symmetric things from a KEM.
 */

extern int setupkem(kem */*k*/, dstr */*d*/,
		    gcipher **/*cx*/, gcipher **/*c*/, gmac **/*m*/);

/* --- @freekem@ --- *
 *
 * Arguments:	@kem *k@ = key-encapsulation thing
 *
 * Returns:	---
 *
 * Use:		Frees up a key-encapsulation thing.
 */

extern void freekem(kem */*k*/);

/* --- @getsig@ --- *
 *
 * Arguments:	@key *k@ = the key to load
 *		@const char *app@ = application name
 *		@int wantpriv@ = nonzero if we want to sign
 *
 * Returns:	A signature-making thing.
 *
 * Use:		Loads a key and starts hashing.
 */

extern sig *getsig(key */*k*/, const char */*app*/, int /*wantpriv*/);

/* --- @freesig@ --- *
 *
 * Arguments:	@sig *s@ = signature-making thing
 *
 * Returns:	---
 *
 * Use:		Frees up a signature-making thing
 */

extern void freesig(sig */*s*/);

/* --- @getenc@ --- *
 *
 * Arguments:	@const char *enc@ = name of wanted encoding
 *
 * Returns:	Pointer to encoder operations.
 *
 * Use:		Finds a named encoder or decoder.
 */

extern const encops *getenc(const char */*enc*/);

/* --- @initenc@ --- *
 *
 * Arguments:	@const encops *eo@ = operations (from @getenc@)
 *		@FILE *fp@ = file handle to attach
 *		@const char *msg@ = banner message
 *		@int wantenc@ = nonzero if we want to encode
 *
 * Returns:	The encoder object.
 *
 * Use:		Initializes an encoder.
 */

extern enc *initenc(const encops */*eo*/, FILE */*fp*/,
		    const char */*msg*/, int /*wantenc*/);

/* --- @freeenc@ --- *
 *
 * Arguments:	@enc *e@ = encoder object
 *
 * Returns:	---
 *
 * Use:		Frees an encoder object.
 */

extern void freeenc(enc */*e*/);

/* --- @LIST(STRING, FP, END-TEST, NAME-EXPR)@ --- *
 *
 * Produce list of things.  Requires @i@ and @w@ variables in scope.
 * END-TEST and NAME-EXPR are in terms of @i@.
 */

#define LIST(what, fp, end, name) do {					\
  fputs(what ":\n  ", fp);						\
  w = 2;								\
  for (i = 0; end; i++) {						\
    if (w == 2)								\
      w += strlen(name);						\
    else {								\
      if (strlen(name) + w > 76) {					\
	fputs("\n  ", fp);						\
	w = 2 + strlen(name);						\
      } else {								\
	fputc(' ', fp);							\
	w += strlen(name) + 1;						\
      }									\
    }									\
    fputs(name, fp);							\
  }									\
  fputc('\n', fp);							\
} while (0)

#define STDLISTS(LI)							\
  LI("Hash functions", hash,						\
     ghashtab[i], ghashtab[i]->name)					\
  LI("Encryption schemes", enc,						\
     gciphertab[i], gciphertab[i]->name)				\
  LI("Message authentication schemes", mac,				\
     gmactab[i], gmactab[i]->name)					\
  LI("Elliptic curves", ec,						\
     ectab[i].name, ectab[i].name)					\
  LI("Diffie-Hellman groups", dh,					\
     ptab[i].name, ptab[i].name)

#define LIDECL(text, tag, test, name)					\
  static void show_##tag(void);

#define LIDEF(text, tag, test, name)					\
  static void show_##tag(void)						\
  {									\
    unsigned i, w;							\
    LIST(text, stdout, test, name);					\
  }

#define LIENT(text, tag, test, name)					\
  { #tag, show_##tag },

struct listent {
  const char *name;
  void (*list)(void);
};

#define MAKELISTTAB(listtab, LISTS)					\
  LISTS(LIDECL)								\
  static const struct listent listtab[] = {				\
    LISTS(LIENT)							\
    { 0, 0 }								\
  };									\
  LISTS(LIDEF)

extern int displaylists(const struct listent */*listtab*/,
			char *const /*argv*/[]);

/*----- Subcommand dispatch -----------------------------------------------*/

typedef struct cmd {
  const char *name;
  int (*cmd)(int /*argc*/, char */*argv*/[]);
  const char *usage;
  const char *help;
} cmd;

extern void version(FILE */*fp*/);
extern void help_global(FILE */*fp*/);

/* --- @findcmd@ --- *
 *
 * Arguments:	@const cmd *cmds@ = pointer to command table
 *		@const char *name@ = a command name
 *
 * Returns:	Pointer to the command structure.
 *
 * Use:		Looks up a command by name.  If the command isn't found, an
 *		error is reported and the program is terminated.
 */

const cmd *findcmd(const cmd */*cmds*/, const char */*name*/);

/* --- @sc_help@ --- *
 *
 * Arguments:	@const cmd *cmds@ = pointer to command table
 *		@FILE *fp@ = output file handle
 *		@char *const *argv@ = remaining arguments
 *
 * Returns:	---
 *
 * Use:		Prints a help message, maybe with help about subcommands.
 */

extern void sc_help(const cmd */*cmds*/, FILE */*fp*/,
		    char *const */*argv*/);

/*----- That's all, folks -------------------------------------------------*/

#ifdef __cplusplus
  }
#endif

#endif