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56 #include "gssapiP_eap.h"
59 * Caller must provide TOKEN | DATA | PADDING | TRAILER, except
60 * for DCE in which case it can just provide TOKEN | DATA (must
61 * guarantee that DATA is padded)
64 unwrapToken(OM_uint32 *minor,
68 gss_iov_buffer_desc *iov,
70 enum gss_eap_token_type toktype)
73 gss_iov_buffer_t header;
74 gss_iov_buffer_t padding;
75 gss_iov_buffer_t trailer;
77 unsigned char *ptr = NULL;
80 size_t dataLen, assocDataLen;
84 krb5_context krbContext;
86 GSSEAP_KRB_INIT(&krbContext);
90 if (qop_state != NULL)
91 *qop_state = GSS_C_QOP_DEFAULT;
93 header = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER);
94 assert(header != NULL);
96 padding = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING);
97 if (padding != NULL && padding->buffer.length != 0) {
98 *minor = GSSEAP_BAD_PADDING_IOV;
99 return GSS_S_DEFECTIVE_TOKEN;
102 trailer = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER);
104 flags = rfc4121Flags(ctx, TRUE);
106 if (toktype == TOK_TYPE_WRAP) {
107 keyUsage = !CTX_IS_INITIATOR(ctx)
108 ? KEY_USAGE_INITIATOR_SEAL
109 : KEY_USAGE_ACCEPTOR_SEAL;
111 keyUsage = !CTX_IS_INITIATOR(ctx)
112 ? KEY_USAGE_INITIATOR_SIGN
113 : KEY_USAGE_ACCEPTOR_SIGN;
116 gssEapIovMessageLength(iov, iov_count, &dataLen, &assocDataLen);
118 ptr = (unsigned char *)header->buffer.value;
120 if (header->buffer.length < 16) {
121 *minor = GSSEAP_WRONG_SIZE;
122 return GSS_S_DEFECTIVE_TOKEN;
125 if ((ptr[2] & flags) != flags) {
126 *minor = GSSEAP_BAD_DIRECTION;
127 return GSS_S_BAD_SIG;
130 if (toktype == TOK_TYPE_WRAP) {
131 unsigned int krbTrailerLen;
133 if (load_uint16_be(ptr) != TOK_TYPE_WRAP)
135 conf_flag = ((ptr[2] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
138 ec = load_uint16_be(ptr + 4);
139 rrc = load_uint16_be(ptr + 6);
140 seqnum = load_uint64_be(ptr + 8);
142 code = krb5_c_crypto_length(krbContext,
144 conf_flag ? KRB5_CRYPTO_TYPE_TRAILER :
145 KRB5_CRYPTO_TYPE_CHECKSUM,
149 return GSS_S_FAILURE;
153 if (trailer == NULL) {
154 size_t desired_rrc = krbTrailerLen;
157 desired_rrc += 16; /* E(Header) */
159 if ((ctx->gssFlags & GSS_C_DCE_STYLE) == 0)
163 /* According to MS, we only need to deal with a fixed RRC for DCE */
164 if (rrc != desired_rrc)
166 } else if (rrc != 0) {
171 unsigned char *althdr;
174 code = gssEapDecrypt(krbContext,
175 ((ctx->gssFlags & GSS_C_DCE_STYLE) != 0),
176 ec, rrc, &ctx->rfc3961Key,
177 keyUsage, 0, iov, iov_count);
180 return GSS_S_BAD_SIG;
183 /* Validate header integrity */
185 althdr = (unsigned char *)header->buffer.value + 16 + ec;
187 althdr = (unsigned char *)trailer->buffer.value + ec;
189 if (load_uint16_be(althdr) != TOK_TYPE_WRAP
190 || althdr[2] != ptr[2]
191 || althdr[3] != ptr[3]
192 || memcmp(althdr + 8, ptr + 8, 8) != 0) {
193 *minor = GSSEAP_BAD_WRAP_TOKEN;
194 return GSS_S_BAD_SIG;
197 /* Verify checksum: note EC is checksum size here, not padding */
198 if (ec != krbTrailerLen)
201 /* Zero EC, RRC before computing checksum */
202 store_uint16_be(0, ptr + 4);
203 store_uint16_be(0, ptr + 6);
205 code = gssEapVerify(krbContext, ctx->checksumType, rrc,
206 &ctx->rfc3961Key, keyUsage,
207 iov, iov_count, &valid);
208 if (code != 0 || valid == FALSE) {
210 return GSS_S_BAD_SIG;
214 code = sequenceCheck(minor, &ctx->seqState, seqnum);
215 } else if (toktype == TOK_TYPE_MIC) {
216 if (load_uint16_be(ptr) != toktype)
222 seqnum = load_uint64_be(ptr + 8);
224 code = gssEapVerify(krbContext, ctx->checksumType, 0,
225 &ctx->rfc3961Key, keyUsage,
226 iov, iov_count, &valid);
227 if (code != 0 || valid == FALSE) {
229 return GSS_S_BAD_SIG;
231 code = sequenceCheck(minor, &ctx->seqState, seqnum);
232 } else if (toktype == TOK_TYPE_DELETE_CONTEXT) {
233 if (load_uint16_be(ptr) != TOK_TYPE_DELETE_CONTEXT)
242 if (conf_state != NULL)
243 *conf_state = conf_flag;
248 *minor = GSSEAP_BAD_WRAP_TOKEN;
250 return GSS_S_DEFECTIVE_TOKEN;
254 rotateLeft(void *ptr, size_t bufsiz, size_t rc)
264 tbuf = GSSEAP_MALLOC(rc);
268 memcpy(tbuf, ptr, rc);
269 memmove(ptr, (char *)ptr + rc, bufsiz - rc);
270 memcpy((char *)ptr + bufsiz - rc, tbuf, rc);
277 * Split a STREAM | SIGN_DATA | DATA into
278 * HEADER | SIGN_DATA | DATA | PADDING | TRAILER
281 unwrapStream(OM_uint32 *minor,
284 gss_qop_t *qop_state,
285 gss_iov_buffer_desc *iov,
287 enum gss_eap_token_type toktype)
290 OM_uint32 code = 0, major = GSS_S_FAILURE;
291 krb5_context krbContext;
292 int conf_req_flag, toktype2;
294 gss_iov_buffer_desc *tiov = NULL;
295 gss_iov_buffer_t stream, data = NULL;
296 gss_iov_buffer_t theader, tdata = NULL, tpadding, ttrailer;
298 GSSEAP_KRB_INIT(&krbContext);
300 assert(toktype == TOK_TYPE_WRAP);
302 if (toktype != TOK_TYPE_WRAP) {
303 code = GSSEAP_WRONG_TOK_ID;
307 stream = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM);
308 assert(stream != NULL);
310 if (stream->buffer.length < 16) {
311 major = GSS_S_DEFECTIVE_TOKEN;
315 ptr = (unsigned char *)stream->buffer.value;
316 toktype2 = load_uint16_be(ptr);
319 tiov = (gss_iov_buffer_desc *)GSSEAP_CALLOC((size_t)iov_count + 2,
320 sizeof(gss_iov_buffer_desc));
327 theader = &tiov[i++];
328 theader->type = GSS_IOV_BUFFER_TYPE_HEADER;
329 theader->buffer.value = stream->buffer.value;
330 theader->buffer.length = 16;
332 /* n[SIGN_DATA] | DATA | m[SIGN_DATA] */
333 for (j = 0; j < iov_count; j++) {
334 OM_uint32 type = GSS_IOV_BUFFER_TYPE(iov[j].type);
336 if (type == GSS_IOV_BUFFER_TYPE_DATA) {
338 /* only a single DATA buffer can appear */
339 code = GSSEAP_BAD_STREAM_IOV;
346 if (type == GSS_IOV_BUFFER_TYPE_DATA ||
347 type == GSS_IOV_BUFFER_TYPE_SIGN_ONLY)
352 /* a single DATA buffer must be present */
353 code = GSSEAP_BAD_STREAM_IOV;
357 /* PADDING | TRAILER */
358 tpadding = &tiov[i++];
359 tpadding->type = GSS_IOV_BUFFER_TYPE_PADDING;
360 tpadding->buffer.length = 0;
361 tpadding->buffer.value = NULL;
363 ttrailer = &tiov[i++];
364 ttrailer->type = GSS_IOV_BUFFER_TYPE_TRAILER;
368 unsigned int krbHeaderLen = 0;
369 unsigned int krbTrailerLen = 0;
371 conf_req_flag = ((ptr[0] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
372 ec = conf_req_flag ? load_uint16_be(ptr + 2) : 0;
373 rrc = load_uint16_be(ptr + 4);
376 code = rotateLeft((unsigned char *)stream->buffer.value + 16,
377 stream->buffer.length - 16, rrc);
380 store_uint16_be(0, ptr + 4); /* set RRC to zero */
384 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
385 KRB5_CRYPTO_TYPE_HEADER, &krbHeaderLen);
388 theader->buffer.length += krbHeaderLen; /* length validated later */
391 /* no PADDING for CFX, EC is used instead */
392 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
394 ? KRB5_CRYPTO_TYPE_TRAILER
395 : KRB5_CRYPTO_TYPE_CHECKSUM,
400 ttrailer->buffer.length = ec + (conf_req_flag ? 16 : 0 /* E(Header) */) +
402 ttrailer->buffer.value = (unsigned char *)stream->buffer.value +
403 stream->buffer.length - ttrailer->buffer.length;
406 /* IOV: -----------0-------------+---1---+--2--+----------------3--------------*/
407 /* CFX: GSS-Header | Kerb-Header | Data | | EC | E(Header) | Kerb-Trailer */
408 /* GSS: -------GSS-HEADER--------+-DATA--+-PAD-+----------GSS-TRAILER----------*/
410 /* validate lengths */
411 if (stream->buffer.length < theader->buffer.length +
412 tpadding->buffer.length +
413 ttrailer->buffer.length) {
414 code = GSSEAP_WRONG_SIZE;
415 major = GSS_S_DEFECTIVE_TOKEN;
420 tdata->buffer.length = stream->buffer.length - ttrailer->buffer.length -
421 tpadding->buffer.length - theader->buffer.length;
423 assert(data != NULL);
425 if (data->type & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
426 code = gssEapAllocIov(tdata, tdata->buffer.length);
430 memcpy(tdata->buffer.value,
431 (unsigned char *)stream->buffer.value + theader->buffer.length,
432 tdata->buffer.length);
434 tdata->buffer.value = (unsigned char *)stream->buffer.value +
435 theader->buffer.length;
438 assert(i <= iov_count + 2);
440 major = unwrapToken(&code, ctx, conf_state, qop_state,
442 if (major == GSS_S_COMPLETE) {
444 } else if (tdata->type & GSS_IOV_BUFFER_FLAG_ALLOCATED) {
447 gss_release_buffer(&tmp, &tdata->buffer);
448 tdata->type &= ~(GSS_IOV_BUFFER_FLAG_ALLOCATED);
461 gssEapUnwrapOrVerifyMIC(OM_uint32 *minor,
464 gss_qop_t *qop_state,
465 gss_iov_buffer_desc *iov,
467 enum gss_eap_token_type toktype)
471 if (ctx->encryptionType == ENCTYPE_NULL) {
472 *minor = GSSEAP_KEY_UNAVAILABLE;
473 return GSS_S_UNAVAILABLE;
476 if (gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM) != NULL) {
477 major = unwrapStream(minor, ctx, conf_state, qop_state,
478 iov, iov_count, toktype);
480 major = unwrapToken(minor, ctx, conf_state, qop_state,
481 iov, iov_count, toktype);
488 gss_unwrap_iov(OM_uint32 *minor,
491 gss_qop_t *qop_state,
492 gss_iov_buffer_desc *iov,
497 if (ctx == GSS_C_NO_CONTEXT) {
499 return GSS_S_NO_CONTEXT;
504 GSSEAP_MUTEX_LOCK(&ctx->mutex);
506 if (!CTX_IS_ESTABLISHED(ctx)) {
507 *minor = GSSEAP_CONTEXT_INCOMPLETE;
508 major = GSS_S_NO_CONTEXT;
512 major = gssEapUnwrapOrVerifyMIC(minor, ctx, conf_state, qop_state,
513 iov, iov_count, TOK_TYPE_WRAP);
514 if (GSS_ERROR(major))
518 GSSEAP_MUTEX_UNLOCK(&ctx->mutex);