1  /*
  2   * Copyright (c) 1997 - 2003 Kungliga Tekniska Högskolan
  3   * (Royal Institute of Technology, Stockholm, Sweden).
  4   * All rights reserved.
  5   *
  6   * Redistribution and use in source and binary forms, with or without
  7   * modification, are permitted provided that the following conditions
  8   * are met:
  9   *
 10   * 1. Redistributions of source code must retain the above copyright
 11   *    notice, this list of conditions and the following disclaimer.
 12   *
 13   * 2. Redistributions in binary form must reproduce the above copyright
 14   *    notice, this list of conditions and the following disclaimer in the
 15   *    documentation and/or other materials provided with the distribution.
 16   *
 17   * 3. Neither the name of the Institute nor the names of its contributors
 18   *    may be used to endorse or promote products derived from this software
 19   *    without specific prior written permission.
 20   *
 21   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 22   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 23   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 24   * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 25   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 26   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 27   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 28   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 29   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 30   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 31   * SUCH DAMAGE.
 32   */
 33  
 34  #include "gsskrb5_locl.h"
 35  
 36  void
 37  _gssapi_encap_length (size_t data_len,
 38  		      size_t *len,
 39  		      size_t *total_len,
 40  		      const gss_OID mech)
 41  {
 42      size_t len_len;
 43  
 44      *len = 1 + 1 + mech->length + data_len;
 45  
 46      len_len = der_length_len(*len);
 47  
 48      *total_len = 1 + len_len + *len;
 49  }
 50  
 51  void
 52  _gsskrb5_encap_length (size_t data_len,
 53  			  size_t *len,
 54  			  size_t *total_len,
 55  			  const gss_OID mech)
 56  {
 57      _gssapi_encap_length(data_len + 2, len, total_len, mech);
 58  }
 59  
 60  void *
 61  _gsskrb5_make_header (void *ptr,
 62  			 size_t len,
 63  			 const void *type,
 64  			 const gss_OID mech)
 65  {
 66      u_char *p = ptr;
 67      p = _gssapi_make_mech_header(p, len, mech);
 68      memcpy (p, type, 2);
 69      p += 2;
 70      return p;
 71  }
 72  
 73  void *
 74  _gssapi_make_mech_header(void *ptr,
 75  			 size_t len,
 76  			 const gss_OID mech)
 77  {
 78      u_char *p = ptr;
 79      int e;
 80      size_t len_len, foo;
 81  
 82      *p++ = 0x60;
 83      len_len = der_length_len(len);
 84      e = der_put_length (p + len_len - 1, len_len, len, &foo);
 85      if(e || foo != len_len)
 86  	abort ();
 87      p += len_len;
 88      *p++ = 0x06;
 89      *p++ = mech->length;
 90      memcpy (p, mech->elements, mech->length);
 91      p += mech->length;
 92      return p;
 93  }
 94  
 95  /*
 96   * Give it a krb5_data and it will encapsulate with extra GSS-API wrappings.
 97   */
 98  
 99  OM_uint32
100  _gssapi_encapsulate(
101      OM_uint32 *minor_status,
102      const krb5_data *in_data,
103      gss_buffer_t output_token,
104      const gss_OID mech
105  )
106  {
107      size_t len, outer_len;
108      void *p;
109  
110      _gssapi_encap_length (in_data->length, &len, &outer_len, mech);
111  
112      output_token->length = outer_len;
113      output_token->value  = malloc (outer_len);
114      if (output_token->value == NULL) {
115  	*minor_status = ENOMEM;
116  	return GSS_S_FAILURE;
117      }
118  
119      p = _gssapi_make_mech_header (output_token->value, len, mech);
120      memcpy (p, in_data->data, in_data->length);
121      return GSS_S_COMPLETE;
122  }
123  
124  /*
125   * Give it a krb5_data and it will encapsulate with extra GSS-API krb5
126   * wrappings.
127   */
128  
129  OM_uint32
130  _gsskrb5_encapsulate(
131  			OM_uint32 *minor_status,
132  			const krb5_data *in_data,
133  			gss_buffer_t output_token,
134  			const void *type,
135  			const gss_OID mech
136  )
137  {
138      size_t len, outer_len;
139      u_char *p;
140  
141      _gsskrb5_encap_length (in_data->length, &len, &outer_len, mech);
142  
143      output_token->length = outer_len;
144      output_token->value  = malloc (outer_len);
145      if (output_token->value == NULL) {
146  	*minor_status = ENOMEM;
147  	return GSS_S_FAILURE;
148      }
149  
150      p = _gsskrb5_make_header (output_token->value, len, type, mech);
151      memcpy (p, in_data->data, in_data->length);
152      return GSS_S_COMPLETE;
153  }