examples/client.c

   1 /* client.c --- Example SASL client.
   2  * Copyright (C) 2004, 2005, 2007  Simon Josefsson
   3  *
   4  * This file is part of GNU SASL.
   5  *
   6  * This program 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 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #include <stdarg.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include <gsasl.h>
  27
  28 static void
  29 client_authenticate (Gsasl * ctx, Gsasl_session * session)
  30 {
  31   char buf[BUFSIZ] = "";
  32   char *p;
  33   int rc;
  34
  35   /* This loop mimic a protocol where the client send data first. */
  36
  37   do
  38     {
  39       /* Generate client output. */
  40       rc = gsasl_step64 (session, buf, &p);
  41
  42       if (rc == GSASL_NEEDS_MORE || rc == GSASL_OK)
  43         {
  44           /* If sucessful, print it. */
  45           printf ("Output:\n%s\n", p);
  46           free (p);
  47         }
  48
  49       if (rc == GSASL_NEEDS_MORE)
  50         {
  51           /* If the client need more data from server, get it here. */
  52           printf ("Input base64 encoded data from server:\n");
  53           fgets (buf, sizeof (buf) - 1, stdin);
  54           if (buf[strlen (buf) - 1] == '\n')
  55             buf[strlen (buf) - 1] = '\0';
  56         }
  57     }
  58   while (rc == GSASL_NEEDS_MORE);
  59
  60   printf ("\n");
  61
  62   if (rc != GSASL_OK)
  63     {
  64       printf ("Authentication error (%d): %s\n", rc, gsasl_strerror (rc));
  65       return;
  66     }
  67
  68   /* The client is done.  Here you would typically check if the server
  69      let the client in.  If not, you could try again. */
  70
  71   printf ("If server accepted us, we're done.\n");
  72 }
  73
  74 static void
  75 client (Gsasl * ctx)
  76 {
  77   Gsasl_session *session;
  78   const char *mech = "PLAIN";
  79   int rc;
  80
  81   /* Create new authentication session. */
  82   if ((rc = gsasl_client_start (ctx, mech, &session)) != GSASL_OK)
  83     {
  84       printf ("Cannot initialize client (%d): %s\n", rc, gsasl_strerror (rc));
  85       return;
  86     }
  87
  88   /* Set username and password in session handle.  This info will be
  89      lost when this session is deallocated below.  */
  90   gsasl_property_set (session, GSASL_AUTHID, "jas");
  91   gsasl_property_set (session, GSASL_PASSWORD, "secret");
  92
  93   /* Do it. */
  94   client_authenticate (ctx, session);
  95
  96   /* Cleanup. */
  97   gsasl_finish (session);
  98 }
  99
 100 int
 101 main (int argc, char *argv[])
 102 {
 103   Gsasl *ctx = NULL;
 104   int rc;
 105
 106   /* Initialize library. */
 107   if ((rc = gsasl_init (&ctx)) != GSASL_OK)
 108     {
 109       printf ("Cannot initialize libgsasl (%d): %s", rc, gsasl_strerror (rc));
 110       return 1;
 111     }
 112
 113   /* Do it. */
 114   client (ctx);
 115
 116   /* Cleanup. */
 117   gsasl_done (ctx);
 118
 119   return 0;
 120 }