ser_rc.c   [plain text]

/*
 * lib/krb5/rcache/ser_rc.c
 *
 * Copyright 1995 by the Massachusetts Institute of Technology.
 * All Rights Reserved.
 *
 * Export of this software from the United States of America may
 *   require a specific license from the United States Government.
 *   It is the responsibility of any person or organization contemplating
 *   export to obtain such a license before exporting.
 *
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of M.I.T. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  Furthermore if you modify this software you must label
 * your software as modified software and not distribute it in such a
 * fashion that it might be confused with the original M.I.T. software.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 *
 */

/*
 * ser_rcdfl.c - Serialize replay cache context.
 */
#include "k5-int.h"
#include "rc-int.h"

/*
 * Routines to deal with externalizing krb5_rcache.
 *	krb5_rcache_size();
 *	krb5_rcache_externalize();
 *	krb5_rcache_internalize();
 */
static krb5_error_code krb5_rcache_size
	(krb5_context, krb5_pointer, size_t *);
static krb5_error_code krb5_rcache_externalize
	(krb5_context, krb5_pointer, krb5_octet **, size_t *);
static krb5_error_code krb5_rcache_internalize
	(krb5_context,krb5_pointer *, krb5_octet **, size_t *);

/*
 * Serialization entry for this type.
 */
static const krb5_ser_entry krb5_rcache_ser_entry = {
    KV5M_RCACHE,			/* Type			*/
    krb5_rcache_size,			/* Sizer routine	*/
    krb5_rcache_externalize,		/* Externalize routine	*/
    krb5_rcache_internalize		/* Internalize routine	*/
};

/*
 * krb5_rcache_size()	- Determine the size required to externalize
 *				  this krb5_rcache variant.
 */
static krb5_error_code
krb5_rcache_size(krb5_context kcontext, krb5_pointer arg, size_t *sizep)
{
    krb5_error_code	kret;
    krb5_rcache		rcache;
    size_t		required;

    kret = EINVAL;
    if ((rcache = (krb5_rcache) arg)) {
	/*
	 * Saving FILE: variants of krb5_rcache requires at minimum:
	 *	krb5_int32	for KV5M_RCACHE
	 *	krb5_int32	for length of rcache name.
	 *	krb5_int32	for KV5M_RCACHE
	 */
	required = sizeof(krb5_int32) * 3;
	if (rcache->ops && rcache->ops->type)
	    required += (strlen(rcache->ops->type)+1);

	/*
	 * The rcache name is formed as follows:
	 *	<type>:<name>
	 */
	required += strlen(krb5_rc_get_name(kcontext, rcache));

	kret = 0;
	*sizep += required;
    }
    return(kret);
}

/*
 * krb5_rcache_externalize()	- Externalize the krb5_rcache.
 */
static krb5_error_code
krb5_rcache_externalize(krb5_context kcontext, krb5_pointer arg, krb5_octet **buffer, size_t *lenremain)
{
    krb5_error_code	kret;
    krb5_rcache		rcache;
    size_t		required;
    krb5_octet		*bp;
    size_t		remain;
    char		*rcname;
    size_t		namelen;
    char		*fnamep;

    required = 0;
    bp = *buffer;
    remain = *lenremain;
    kret = EINVAL;
    if ((rcache = (krb5_rcache) arg)) {
	kret = ENOMEM;
	if (!krb5_rcache_size(kcontext, arg, &required) &&
	    (required <= remain)) {
	    /* Our identifier */
	    (void) krb5_ser_pack_int32(KV5M_RCACHE, &bp, &remain);

	    /* Calculate the length of the name */
	    namelen = (rcache->ops && rcache->ops->type) ?
		strlen(rcache->ops->type)+1 : 0;
	    fnamep = krb5_rc_get_name(kcontext, rcache);
	    namelen += (strlen(fnamep)+1);

	    if ((rcname = (char *) malloc(namelen))) {
		/* Format the rcache name. */
		if (rcache->ops && rcache->ops->type)
		    sprintf(rcname, "%s:%s", rcache->ops->type, fnamep);
		else
		    strcpy(rcname, fnamep);

		/* Put the length of the file name */
		(void) krb5_ser_pack_int32((krb5_int32) strlen(rcname),
					   &bp, &remain);
		
		/* Put the name */
		(void) krb5_ser_pack_bytes((krb5_octet *) rcname,
					   strlen(rcname),
					   &bp, &remain);

		/* Put the trailer */
		(void) krb5_ser_pack_int32(KV5M_RCACHE, &bp, &remain);
		kret = 0;
		*buffer = bp;
		*lenremain = remain;
		free(rcname);
	    }
	}
    }
    return(kret);
}

/*
 * krb5_rcache_internalize()	- Internalize the krb5_rcache.
 */
static krb5_error_code
krb5_rcache_internalize(krb5_context kcontext, krb5_pointer *argp, krb5_octet **buffer, size_t *lenremain)
{
    krb5_error_code	kret;
    krb5_rcache		rcache;
    krb5_int32		ibuf;
    krb5_octet		*bp;
    size_t		remain;
    char		*rcname;

    bp = *buffer;
    remain = *lenremain;
    kret = EINVAL;
    /* Read our magic number */
    if (krb5_ser_unpack_int32(&ibuf, &bp, &remain))
	ibuf = 0;
    if (ibuf == KV5M_RCACHE) {
	kret = ENOMEM;

	/* Get the length of the rcache name */
	kret = krb5_ser_unpack_int32(&ibuf, &bp, &remain);

	if (!kret &&
	    (rcname = (char *) malloc((size_t) (ibuf+1))) &&
	    !(kret = krb5_ser_unpack_bytes((krb5_octet *) rcname,
					   (size_t) ibuf,
					   &bp, &remain))) {
	    rcname[ibuf] = '\0';
	    if (!(kret = krb5_rc_resolve_full(kcontext, &rcache, rcname))) {
		(void) krb5_rc_recover(kcontext, rcache);
		if (!kret && 
		    !(kret = krb5_ser_unpack_int32(&ibuf, &bp, &remain)) &&
		    (ibuf == KV5M_RCACHE)) {
		    *buffer = bp;
		    *lenremain = remain;
		    *argp = (krb5_pointer) rcache;
		}
		else
		    krb5_rc_close(kcontext, rcache);
	    }
	    free(rcname);
	}
    }
    return(kret);
}

/*
 * Register the rcache serializer.
 */
krb5_error_code KRB5_CALLCONV
krb5_ser_rcache_init(krb5_context kcontext)
{
    return(krb5_register_serializer(kcontext, &krb5_rcache_ser_entry));
}