/*
 * Copyright (c) 1997 - 2000, 2002 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.
 *
 * $Source: /afs/pdc.kth.se/cluster/povel/src/kdeposit/RCS/kdeposit.c,v $
 *
 */

#include "kdeposit.h"

krb5_context context;
const char *service     = KF_SERVICE;
int remote_forwardable   = 1;
static char *progname;
char* tag = NULL;

static char* usage = 
     "kdeposit -t tag -s server [-g] [-h]\n\n"

     "-t <tag> identifying tag for remote side (typically job id)\n"
     "-g make forwarded tickets non-forwardable \n"
     "-h prints this help\n"
     "-s <server> server to forward tickets to\n";

/*
 * forward creds to `hostname'/`service' over `sock'
 * return 0 iff OK
 */
static int
forward_cred (int sock, const char *hostname, const char *service, 
	      char *message, size_t len)
{
    krb5_auth_context auth_context;
    krb5_error_code status;
    krb5_principal server;
    krb5_data data;
    krb5_data data_send;

    krb5_ccache     ccache;
    krb5_creds      creds;
    krb5_kdc_flags  flags;
    krb5_principal  principal;

    status = krb5_auth_con_init (context, &auth_context);
    if (status) {
	krb5_warn (context, status, "krb5_auth_con_init");
	return 1;
    }

    status = krb5_auth_con_setaddrs_from_fd (context,
					     auth_context,
					     &sock);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_auth_con_setaddr");
	return 1;
    }

    status = krb5_sname_to_principal (context,
				      hostname,
				      service,
				      KRB5_NT_SRV_HST,
				      &server);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_sname_to_principal");
	return 1;
    }

    status = krb5_sendauth (context,
			    &auth_context,
			    &sock,
			    KF_VERSION_1,
			    NULL,
			    server,
			    AP_OPTS_MUTUAL_REQUIRED | AP_OPTS_USE_SUBKEY,
			    NULL,
			    NULL,
			    NULL,
			    NULL,
			    NULL,
			    NULL);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn(context, status, "krb5_sendauth");
	return 1;
    }

    data_send.data   = (void *) tag;
    data_send.length = strlen(tag)+1;
    status = krb5_write_priv_message(context, auth_context, &sock, &data_send);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_write_message");
	return 1;
    }

    memset (&creds, 0, sizeof(creds));

    status = krb5_cc_default (context, &ccache);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_cc_default");
	return 1;
    }

    status = krb5_cc_get_principal (context, ccache, &principal);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_cc_get_principal");
	return 1;
    }

    creds.client = principal;

    status = krb5_make_principal (context,
				  &creds.server,
				  principal->realm,
				  KRB5_TGS_NAME,
				  principal->realm,
				  NULL);

    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_make_principal");
	return 1;
    }

    creds.times.endtime = 0;

    flags.i = 0;
    flags.b.forwarded   = 1;
    flags.b.forwardable = remote_forwardable;

    status = krb5_get_forwarded_creds (context,
				       auth_context,
				       ccache,
				       flags.i,
				       hostname,
				       &creds,
				       &data);
    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_get_forwarded_creds");
	return 1;
    }

    status = krb5_write_priv_message(context, auth_context, &sock, &data);

    if (status) {
	krb5_auth_con_free(context, auth_context);
	krb5_warn (context, status, "krb5_mk_priv");
	return 1;
    }

    krb5_data_free (&data);

    status = krb5_read_priv_message(context, auth_context, &sock, &data);
    krb5_auth_con_free(context, auth_context);
    if (status) {
	krb5_warn (context, status, "krb5_mk_priv");
	return 1;
    }
    if(data.length >= len) {
	krb5_warnx (context, "returned string is too long, truncating");
	memcpy(message, data.data, len);
	message[len - 1] = '\0';
    } else {
	memcpy(message, data.data, data.length);
	message[data.length] = '\0';
    }
    krb5_data_free (&data);

    return(strcmp(message, "ok"));
}

int
main(int argc, char **argv)
{
     int port, status;
     int ret = 0;
     struct addrinfo *ai, *a;
     struct addrinfo hints;
     char* hostname = NULL;
     int error;
     char portstr[NI_MAXSERV];
     int c;
     
     if (argc > 0) {
	  progname = argv[0];
     }

     status = krb5_init_context (&context);
     if (status)
	  errx(1, "krb5_init_context failed: %d", status);
     
     remote_forwardable = krb5_config_get_bool (context, NULL,
						"libdefaults",
						"forwardable",
						NULL);
     while ((c = getopt (argc, argv, "ght:s:")) != -1) {
	  switch (c) {
	  case 'g':
	       remote_forwardable = 0;
	       break;
	  case 'h':
	       fprintf(stderr, "%s", usage);
	       exit(0);
	       break;
	  case 't':
	       if ((tag = strdup(optarg)) == NULL) {
                    perror(progname);
		    exit(1);
               }
	       break;
	  case 's':
	       if ((hostname = strdup(optarg)) == NULL) {
                    perror(progname);
		    exit(1);
               }
	       break;
	  default:
	       fprintf(stderr, "Unable to parse command line\n\n%s", usage);
	       exit(1);
	       break;
	  }
     }

     if (tag == NULL) {
	  fprintf(stderr, "Missing tag\n\n%s", usage);
	  exit(1);
     }

     if (hostname == NULL) {
	  fprintf(stderr, "Missing server to forward to\n\n%s", usage);
	  exit(1);
     }


     port = krb5_getportbyname (context, KF_PORT_NAME, "tcp", KF_PORT_NUM);

     memset (&hints, 0, sizeof(hints));
     hints.ai_socktype = SOCK_STREAM;
     hints.ai_protocol = IPPROTO_TCP;
     
     snprintf (portstr, sizeof(portstr), "%u", ntohs(port));
     
     if ((error = getaddrinfo (hostname, portstr, &hints, &ai)) != 0) {
	fprintf(stderr, "getaddrinfo(%s): %s", hostname, gai_strerror(error));
	exit (1);
     }
     
     for (a = ai; a != NULL; a = a->ai_next) {
	  int s;
	  
	  s = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
	  if (s < 0)
	       continue;
	  if (connect (s, a->ai_addr, a->ai_addrlen) < 0) {
	       warn ("connect(%s)", hostname);
	       close (s);
	       continue;
	  }
	  freeaddrinfo (ai);
	  char message[128];
	  return forward_cred (s, hostname, service, message, sizeof(message));
     }
     warnx ("failed to contact %s", hostname);
     freeaddrinfo (ai);
     
     return ret;
}