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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 return GSS_S_DEFECTIVE_TOKEN;
100 trailer = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER);
102 flags = rfc4121Flags(ctx, TRUE);
106 keyUsage = !CTX_IS_INITIATOR(ctx)
107 ? KEY_USAGE_INITIATOR_SEAL
108 : KEY_USAGE_ACCEPTOR_SEAL;
110 case TOK_TYPE_GSS_CB:
111 keyUsage = KEY_USAGE_CHANNEL_BINDINGS;
115 keyUsage = !CTX_IS_INITIATOR(ctx)
116 ? KEY_USAGE_INITIATOR_SIGN
117 : KEY_USAGE_ACCEPTOR_SIGN;
121 gssEapIovMessageLength(iov, iov_count, &dataLen, &assocDataLen);
123 ptr = (unsigned char *)header->buffer.value;
125 if (header->buffer.length < 16)
126 return GSS_S_DEFECTIVE_TOKEN;
128 if ((ptr[2] & flags) != flags)
129 return GSS_S_BAD_SIG;
131 if (toktype == TOK_TYPE_WRAP) {
132 unsigned int krbTrailerLen;
134 if (load_uint16_be(ptr) != TOK_TYPE_WRAP)
136 conf_flag = ((ptr[2] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
139 ec = load_uint16_be(ptr + 4);
140 rrc = load_uint16_be(ptr + 6);
141 seqnum = load_uint64_be(ptr + 8);
143 code = krb5_c_crypto_length(krbContext,
145 conf_flag ? KRB5_CRYPTO_TYPE_TRAILER :
146 KRB5_CRYPTO_TYPE_CHECKSUM,
150 return GSS_S_FAILURE;
154 if (trailer == NULL) {
155 size_t desired_rrc = krbTrailerLen;
158 desired_rrc += 16; /* E(Header) */
160 if ((ctx->gssFlags & GSS_C_DCE_STYLE) == 0)
164 /* According to MS, we only need to deal with a fixed RRC for DCE */
165 if (rrc != desired_rrc)
167 } else if (rrc != 0) {
172 unsigned char *althdr;
175 code = gssEapDecrypt(krbContext,
176 ((ctx->gssFlags & GSS_C_DCE_STYLE) != 0),
177 ec, rrc, &ctx->rfc3961Key,
178 keyUsage, 0, iov, iov_count);
181 return GSS_S_BAD_SIG;
184 /* Validate header integrity */
186 althdr = (unsigned char *)header->buffer.value + 16 + ec;
188 althdr = (unsigned char *)trailer->buffer.value + ec;
190 if (load_uint16_be(althdr) != TOK_TYPE_WRAP
191 || althdr[2] != ptr[2]
192 || althdr[3] != ptr[3]
193 || memcmp(althdr + 8, ptr + 8, 8) != 0) {
195 return GSS_S_BAD_SIG;
198 /* Verify checksum: note EC is checksum size here, not padding */
199 if (ec != krbTrailerLen)
202 /* Zero EC, RRC before computing checksum */
203 store_uint16_be(0, ptr + 4);
204 store_uint16_be(0, ptr + 6);
206 code = gssEapVerify(krbContext, ctx->checksumType, rrc,
207 &ctx->rfc3961Key, keyUsage,
208 iov, iov_count, &valid);
209 if (code != 0 || valid == FALSE) {
211 return GSS_S_BAD_SIG;
215 code = sequenceCheck(minor, &ctx->seqState, seqnum);
216 } else if (toktype == TOK_TYPE_MIC || toktype == TOK_TYPE_GSS_CB) {
217 if (load_uint16_be(ptr) != toktype)
223 seqnum = load_uint64_be(ptr + 8);
225 code = gssEapVerify(krbContext, ctx->checksumType, 0,
226 &ctx->rfc3961Key, keyUsage,
227 iov, iov_count, &valid);
228 if (code != 0 || valid == FALSE) {
230 return GSS_S_BAD_SIG;
232 if (toktype != TOK_TYPE_GSS_CB)
233 code = sequenceCheck(minor, &ctx->seqState, seqnum);
234 } else if (toktype == TOK_TYPE_DELETE_CONTEXT) {
235 if (load_uint16_be(ptr) != TOK_TYPE_DELETE_CONTEXT)
244 if (conf_state != NULL)
245 *conf_state = conf_flag;
252 return GSS_S_DEFECTIVE_TOKEN;
256 rotateLeft(void *ptr, size_t bufsiz, size_t rc)
266 tbuf = GSSEAP_MALLOC(rc);
270 memcpy(tbuf, ptr, rc);
271 memmove(ptr, (char *)ptr + rc, bufsiz - rc);
272 memcpy((char *)ptr + bufsiz - rc, tbuf, rc);
279 * Split a STREAM | SIGN_DATA | DATA into
280 * HEADER | SIGN_DATA | DATA | PADDING | TRAILER
283 unwrapStream(OM_uint32 *minor,
286 gss_qop_t *qop_state,
287 gss_iov_buffer_desc *iov,
289 enum gss_eap_token_type toktype)
292 OM_uint32 code = 0, major = GSS_S_FAILURE;
293 krb5_context krbContext;
294 int conf_req_flag, toktype2;
296 gss_iov_buffer_desc *tiov = NULL;
297 gss_iov_buffer_t stream, data = NULL;
298 gss_iov_buffer_t theader, tdata = NULL, tpadding, ttrailer;
300 GSSEAP_KRB_INIT(&krbContext);
302 assert(toktype == TOK_TYPE_WRAP);
304 if (toktype != TOK_TYPE_WRAP || (ctx->gssFlags & GSS_C_DCE_STYLE)) {
309 stream = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM);
310 assert(stream != NULL);
312 if (stream->buffer.length < 16) {
313 major = GSS_S_DEFECTIVE_TOKEN;
317 ptr = (unsigned char *)stream->buffer.value;
318 toktype2 = load_uint16_be(ptr);
321 tiov = (gss_iov_buffer_desc *)GSSEAP_CALLOC((size_t)iov_count + 2,
322 sizeof(gss_iov_buffer_desc));
329 theader = &tiov[i++];
330 theader->type = GSS_IOV_BUFFER_TYPE_HEADER;
331 theader->buffer.value = stream->buffer.value;
332 theader->buffer.length = 16;
334 /* n[SIGN_DATA] | DATA | m[SIGN_DATA] */
335 for (j = 0; j < iov_count; j++) {
336 OM_uint32 type = GSS_IOV_BUFFER_TYPE(iov[j].type);
338 if (type == GSS_IOV_BUFFER_TYPE_DATA) {
340 /* only a single DATA buffer can appear */
348 if (type == GSS_IOV_BUFFER_TYPE_DATA ||
349 type == GSS_IOV_BUFFER_TYPE_SIGN_ONLY)
354 /* a single DATA buffer must be present */
359 /* PADDING | TRAILER */
360 tpadding = &tiov[i++];
361 tpadding->type = GSS_IOV_BUFFER_TYPE_PADDING;
362 tpadding->buffer.length = 0;
363 tpadding->buffer.value = NULL;
365 ttrailer = &tiov[i++];
366 ttrailer->type = GSS_IOV_BUFFER_TYPE_TRAILER;
370 unsigned int krbHeaderLen = 0;
371 unsigned int krbTrailerLen = 0;
373 conf_req_flag = ((ptr[0] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
374 ec = conf_req_flag ? load_uint16_be(ptr + 2) : 0;
375 rrc = load_uint16_be(ptr + 4);
378 code = rotateLeft((unsigned char *)stream->buffer.value + 16,
379 stream->buffer.length - 16, rrc);
382 store_uint16_be(0, ptr + 4); /* set RRC to zero */
386 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
387 KRB5_CRYPTO_TYPE_HEADER, &krbHeaderLen);
390 theader->buffer.length += krbHeaderLen; /* length validated later */
393 /* no PADDING for CFX, EC is used instead */
394 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
396 ? KRB5_CRYPTO_TYPE_TRAILER
397 : KRB5_CRYPTO_TYPE_CHECKSUM,
402 ttrailer->buffer.length = ec + (conf_req_flag ? 16 : 0 /* E(Header) */) +
404 ttrailer->buffer.value = (unsigned char *)stream->buffer.value +
405 stream->buffer.length - ttrailer->buffer.length;
408 /* IOV: -----------0-------------+---1---+--2--+----------------3--------------*/
409 /* Old: GSS-Header | Conf | Data | Pad | */
410 /* CFX: GSS-Header | Kerb-Header | Data | | EC | E(Header) | Kerb-Trailer */
411 /* GSS: -------GSS-HEADER--------+-DATA--+-PAD-+----------GSS-TRAILER----------*/
413 /* validate lengths */
414 if (stream->buffer.length < theader->buffer.length +
415 tpadding->buffer.length +
416 ttrailer->buffer.length) {
417 code = KRB5_BAD_MSIZE;
418 major = GSS_S_DEFECTIVE_TOKEN;
423 tdata->buffer.length = stream->buffer.length - ttrailer->buffer.length -
424 tpadding->buffer.length - theader->buffer.length;
426 assert(data != NULL);
428 if (data->type & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
429 code = gssEapAllocIov(tdata, tdata->buffer.length);
433 memcpy(tdata->buffer.value,
434 (unsigned char *)stream->buffer.value + theader->buffer.length,
435 tdata->buffer.length);
437 tdata->buffer.value = (unsigned char *)stream->buffer.value +
438 theader->buffer.length;
441 assert(i <= iov_count + 2);
443 major = unwrapToken(&code, ctx, conf_state, qop_state,
445 if (major == GSS_S_COMPLETE) {
447 } else if (tdata->type & GSS_IOV_BUFFER_FLAG_ALLOCATED) {
450 gss_release_buffer(&tmp, &tdata->buffer);
451 tdata->type &= ~(GSS_IOV_BUFFER_FLAG_ALLOCATED);
464 gssEapUnwrapOrVerifyMIC(OM_uint32 *minor,
467 gss_qop_t *qop_state,
468 gss_iov_buffer_desc *iov,
470 enum gss_eap_token_type toktype)
474 if (!CTX_IS_ESTABLISHED(ctx))
475 return GSS_S_NO_CONTEXT;
477 if (ctx->encryptionType == ENCTYPE_NULL)
478 return GSS_S_UNAVAILABLE;
480 if (gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM) != NULL) {
481 major = unwrapStream(minor, ctx, conf_state, qop_state,
482 iov, iov_count, toktype);
484 major = unwrapToken(minor, ctx, conf_state, qop_state,
485 iov, iov_count, toktype);
492 gss_unwrap_iov(OM_uint32 *minor,
495 gss_qop_t *qop_state,
496 gss_iov_buffer_desc *iov,
499 return gssEapUnwrapOrVerifyMIC(minor, ctx, conf_state, qop_state,
500 iov, iov_count, TOK_TYPE_WRAP);