examples/client.c

   1 /* client.c --- Example SASL client.
   2  * Copyright (C) 2004, 2005  Simon Josefsson
   3  *
   4  * This file is part of GNU SASL.
   5  *
   6  * GNU SASL is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * GNU SASL is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with GNU SASL; if not, write to the Free Software
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  *
  20  */
  21
  22 #include <stdarg.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include <gsasl.h>
  28
  29 static void
  30 client_authenticate (Gsasl * ctx, Gsasl_session * session)
  31 {
  32   char buf[BUFSIZ] = "";
  33   char *p;
  34   int rc;
  35
  36   /* This loop mimic a protocol where the client send data first. */
  37
  38   do
  39     {
  40       /* Generate client output. */
  41       rc = gsasl_step64 (session, buf, &p);
  42
  43       if (rc == GSASL_NEEDS_MORE || rc == GSASL_OK)
  44         {
  45           /* If sucessful, print it. */
  46           printf ("Output:\n%s\n", p);
  47           free (p);
  48         }
  49
  50       if (rc == GSASL_NEEDS_MORE)
  51         {
  52           /* If the client need more data from server, get it here. */
  53           printf ("Input base64 encoded data from server:\n");
  54           fgets (buf, sizeof (buf) - 1, stdin);
  55           if (buf[strlen (buf) - 1] == '\n')
  56             buf[strlen (buf) - 1] = '\0';
  57         }
  58     }
  59   while (rc == GSASL_NEEDS_MORE);
  60
  61   printf ("\n");
  62
  63   if (rc != GSASL_OK)
  64     {
  65       printf ("Authentication error (%d): %s\n", rc, gsasl_strerror (rc));
  66       return;
  67     }
  68
  69   /* The client is done.  Here you would typically check if the server
  70      let the client in.  If not, you could try again. */
  71
  72   printf ("If server accepted us, we're done.\n");
  73 }
  74
  75 static void
  76 client (Gsasl * ctx)
  77 {
  78   Gsasl_session *session;
  79   const char *mech = "PLAIN";
  80   int rc;
  81
  82   /* Create new authentication session. */
  83   if ((rc = gsasl_client_start (ctx, mech, &session)) != GSASL_OK)
  84     {
  85       printf ("Cannot initialize client (%d): %s\n", rc, gsasl_strerror (rc));
  86       return;
  87     }
  88
  89   /* Set username and password in session handle.  This info will be
  90      lost when this session is deallocated below.  */
  91   gsasl_property_set (session, GSASL_AUTHID, "jas");
  92   gsasl_property_set (session, GSASL_PASSWORD, "secret");
  93
  94   /* Do it. */
  95   client_authenticate (ctx, session);
  96
  97   /* Cleanup. */
  98   gsasl_finish (session);
  99 }
 100
 101 int
 102 main (int argc, char *argv[])
 103 {
 104   Gsasl *ctx = NULL;
 105   int rc;
 106
 107   /* Initialize library. */
 108   if ((rc = gsasl_init (&ctx)) != GSASL_OK)
 109     {
 110       printf ("Cannot initialize libgsasl (%d): %s", rc, gsasl_strerror (rc));
 111       return 1;
 112     }
 113
 114   /* Do it. */
 115   client (ctx);
 116
 117   /* Cleanup. */
 118   gsasl_done (ctx);
 119
 120   return 0;
 121 }