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34 #include "gssapi_locl.h"
36 RCSID("$Id: unwrap.c,v 1.22.2.1 2003/09/18 22:05:22 lha Exp $");
39 gss_krb5_get_remotekey(const gss_ctx_id_t context_handle,
44 krb5_auth_con_getremotesubkey(gssapi_krb5_context,
45 context_handle->auth_context,
48 krb5_auth_con_getlocalsubkey(gssapi_krb5_context,
49 context_handle->auth_context,
52 krb5_auth_con_getkey(gssapi_krb5_context,
53 context_handle->auth_context,
56 return GSS_KRB5_S_KG_NO_SUBKEY; /* XXX */
63 (OM_uint32 * minor_status,
64 const gss_ctx_id_t context_handle,
65 const gss_buffer_t input_message_buffer,
66 gss_buffer_t output_message_buffer,
68 gss_qop_t * qop_state,
75 u_char hash[16], seq_data[8];
76 des_key_schedule schedule;
85 p = input_message_buffer->value;
86 ret = gssapi_krb5_verify_header (&p,
87 input_message_buffer->length,
92 if (memcmp (p, "\x00\x00", 2) != 0)
95 if (memcmp (p, "\x00\x00", 2) == 0) {
97 } else if (memcmp (p, "\xFF\xFF", 2) == 0) {
100 return GSS_S_BAD_MIC;
102 if(conf_state != NULL)
103 *conf_state = cstate;
104 if (memcmp (p, "\xff\xff", 2) != 0)
105 return GSS_S_DEFECTIVE_TOKEN;
109 len = p - (u_char *)input_message_buffer->value;
113 memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
115 for (i = 0; i < sizeof(deskey); ++i)
117 des_set_key (&deskey, schedule);
118 memset (&zero, 0, sizeof(zero));
119 des_cbc_encrypt ((void *)p,
121 input_message_buffer->length - len,
126 memset (deskey, 0, sizeof(deskey));
127 memset (schedule, 0, sizeof(schedule));
131 pad = (u_char *)input_message_buffer->value + input_message_buffer->length - 1;
134 for (i = padlength; i > 0 && *pad == padlength; i--, pad--)
137 return GSS_S_BAD_MIC;
140 MD5_Update (&md5, p - 24, 8);
141 MD5_Update (&md5, p, input_message_buffer->length - len);
142 MD5_Final (hash, &md5);
144 memset (&zero, 0, sizeof(zero));
145 memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
146 des_set_key (&deskey, schedule);
147 des_cbc_cksum ((void *)hash, (void *)hash, sizeof(hash),
149 if (memcmp (p - 8, hash, 8) != 0)
150 return GSS_S_BAD_MIC;
152 /* verify sequence number */
154 krb5_auth_getremoteseqnumber (gssapi_krb5_context,
155 context_handle->auth_context,
157 seq_data[0] = (seq_number >> 0) & 0xFF;
158 seq_data[1] = (seq_number >> 8) & 0xFF;
159 seq_data[2] = (seq_number >> 16) & 0xFF;
160 seq_data[3] = (seq_number >> 24) & 0xFF;
161 memset (seq_data + 4,
162 (context_handle->more_flags & LOCAL) ? 0xFF : 0,
166 des_set_key (&deskey, schedule);
167 des_cbc_encrypt ((void *)p, (void *)p, 8,
168 schedule, (des_cblock *)hash, DES_DECRYPT);
170 memset (deskey, 0, sizeof(deskey));
171 memset (schedule, 0, sizeof(schedule));
173 if (memcmp (p, seq_data, 8) != 0) {
174 return GSS_S_BAD_MIC;
177 krb5_auth_con_setremoteseqnumber (gssapi_krb5_context,
178 context_handle->auth_context,
183 output_message_buffer->length = input_message_buffer->length
184 - len - padlength - 8;
185 output_message_buffer->value = malloc(output_message_buffer->length);
186 if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
187 return GSS_S_FAILURE;
188 memcpy (output_message_buffer->value,
190 output_message_buffer->length);
191 return GSS_S_COMPLETE;
196 (OM_uint32 * minor_status,
197 const gss_ctx_id_t context_handle,
198 const gss_buffer_t input_message_buffer,
199 gss_buffer_t output_message_buffer,
201 gss_qop_t * qop_state,
219 p = input_message_buffer->value;
220 ret = gssapi_krb5_verify_header (&p,
221 input_message_buffer->length,
226 if (memcmp (p, "\x04\x00", 2) != 0) /* HMAC SHA1 DES3_KD */
227 return GSS_S_BAD_SIG;
229 if (memcmp (p, "\x02\x00", 2) == 0) {
231 } else if (memcmp (p, "\xff\xff", 2) == 0) {
234 return GSS_S_BAD_MIC;
236 if(conf_state != NULL)
237 *conf_state = cstate;
238 if (memcmp (p, "\xff\xff", 2) != 0)
239 return GSS_S_DEFECTIVE_TOKEN;
243 len = p - (u_char *)input_message_buffer->value;
249 ret = krb5_crypto_init(gssapi_krb5_context, key,
250 ETYPE_DES3_CBC_NONE, &crypto);
252 gssapi_krb5_set_error_string ();
254 return GSS_S_FAILURE;
256 ret = krb5_decrypt(gssapi_krb5_context, crypto, KRB5_KU_USAGE_SEAL,
257 p, input_message_buffer->length - len, &tmp);
258 krb5_crypto_destroy(gssapi_krb5_context, crypto);
260 gssapi_krb5_set_error_string ();
262 return GSS_S_FAILURE;
264 assert (tmp.length == input_message_buffer->length - len);
266 memcpy (p, tmp.data, tmp.length);
267 krb5_data_free(&tmp);
271 pad = (u_char *)input_message_buffer->value + input_message_buffer->length - 1;
274 for (i = padlength; i > 0 && *pad == padlength; i--, pad--)
277 return GSS_S_BAD_MIC;
279 /* verify sequence number */
281 krb5_auth_getremoteseqnumber (gssapi_krb5_context,
282 context_handle->auth_context,
284 seq[0] = (seq_number >> 0) & 0xFF;
285 seq[1] = (seq_number >> 8) & 0xFF;
286 seq[2] = (seq_number >> 16) & 0xFF;
287 seq[3] = (seq_number >> 24) & 0xFF;
289 (context_handle->more_flags & LOCAL) ? 0xFF : 0,
294 ret = krb5_crypto_init(gssapi_krb5_context, key,
295 ETYPE_DES3_CBC_NONE, &crypto);
297 gssapi_krb5_set_error_string ();
299 return GSS_S_FAILURE;
304 memcpy(&ivec, p + 8, 8);
305 ret = krb5_decrypt_ivec (gssapi_krb5_context,
311 krb5_crypto_destroy (gssapi_krb5_context, crypto);
313 gssapi_krb5_set_error_string ();
315 return GSS_S_FAILURE;
317 if (seq_data.length != 8) {
318 krb5_data_free (&seq_data);
319 return GSS_S_BAD_MIC;
322 cmp = memcmp (seq, seq_data.data, seq_data.length);
323 krb5_data_free (&seq_data);
325 return GSS_S_BAD_MIC;
328 krb5_auth_con_setremoteseqnumber (gssapi_krb5_context,
329 context_handle->auth_context,
332 /* verify checksum */
334 memcpy (cksum, p + 8, 20);
336 memcpy (p + 20, p - 8, 8);
338 csum.cksumtype = CKSUMTYPE_HMAC_SHA1_DES3;
339 csum.checksum.length = 20;
340 csum.checksum.data = cksum;
342 ret = krb5_crypto_init(gssapi_krb5_context, key, 0, &crypto);
344 gssapi_krb5_set_error_string ();
346 return GSS_S_FAILURE;
349 ret = krb5_verify_checksum (gssapi_krb5_context, crypto,
352 input_message_buffer->length - len + 8,
354 krb5_crypto_destroy (gssapi_krb5_context, crypto);
356 gssapi_krb5_set_error_string ();
358 return GSS_S_FAILURE;
363 output_message_buffer->length = input_message_buffer->length
364 - len - padlength - 8;
365 output_message_buffer->value = malloc(output_message_buffer->length);
366 if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
367 return GSS_S_FAILURE;
368 memcpy (output_message_buffer->value,
370 output_message_buffer->length);
371 return GSS_S_COMPLETE;
375 (OM_uint32 * minor_status,
376 const gss_ctx_id_t context_handle,
377 const gss_buffer_t input_message_buffer,
378 gss_buffer_t output_message_buffer,
380 gss_qop_t * qop_state
385 krb5_keytype keytype;
387 if (qop_state != NULL)
388 *qop_state = GSS_C_QOP_DEFAULT;
389 ret = gss_krb5_get_remotekey(context_handle, &key);
391 gssapi_krb5_set_error_string ();
393 return GSS_S_FAILURE;
395 krb5_enctype_to_keytype (gssapi_krb5_context, key->keytype, &keytype);
401 ret = unwrap_des (minor_status, context_handle,
402 input_message_buffer, output_message_buffer,
403 conf_state, qop_state, key);
406 ret = unwrap_des3 (minor_status, context_handle,
407 input_message_buffer, output_message_buffer,
408 conf_state, qop_state, key);
410 case KEYTYPE_ARCFOUR:
411 ret = _gssapi_unwrap_arcfour (minor_status, context_handle,
412 input_message_buffer, output_message_buffer,
413 conf_state, qop_state, key);
416 *minor_status = KRB5_PROG_ETYPE_NOSUPP;
420 krb5_free_keyblock (gssapi_krb5_context, key);