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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);
104 if (toktype == TOK_TYPE_WRAP) {
105 keyUsage = !CTX_IS_INITIATOR(ctx)
106 ? KEY_USAGE_INITIATOR_SEAL
107 : KEY_USAGE_ACCEPTOR_SEAL;
109 keyUsage = !CTX_IS_INITIATOR(ctx)
110 ? KEY_USAGE_INITIATOR_SIGN
111 : KEY_USAGE_ACCEPTOR_SIGN;
114 gssEapIovMessageLength(iov, iov_count, &dataLen, &assocDataLen);
116 ptr = (unsigned char *)header->buffer.value;
118 if (header->buffer.length < 16)
119 return GSS_S_DEFECTIVE_TOKEN;
121 if ((ptr[2] & flags) != flags)
122 return GSS_S_BAD_SIG;
124 if (toktype == TOK_TYPE_WRAP) {
125 unsigned int krbTrailerLen;
127 if (load_uint16_be(ptr) != TOK_TYPE_WRAP)
129 conf_flag = ((ptr[2] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
132 ec = load_uint16_be(ptr + 4);
133 rrc = load_uint16_be(ptr + 6);
134 seqnum = load_uint64_be(ptr + 8);
136 code = krb5_c_crypto_length(krbContext,
138 conf_flag ? KRB5_CRYPTO_TYPE_TRAILER :
139 KRB5_CRYPTO_TYPE_CHECKSUM,
143 return GSS_S_FAILURE;
147 if (trailer == NULL) {
148 size_t desired_rrc = krbTrailerLen;
151 desired_rrc += 16; /* E(Header) */
153 if ((ctx->gssFlags & GSS_C_DCE_STYLE) == 0)
157 /* According to MS, we only need to deal with a fixed RRC for DCE */
158 if (rrc != desired_rrc)
160 } else if (rrc != 0) {
165 unsigned char *althdr;
168 code = gssEapDecrypt(krbContext,
169 ((ctx->gssFlags & GSS_C_DCE_STYLE) != 0),
170 ec, rrc, &ctx->rfc3961Key,
171 keyUsage, 0, iov, iov_count);
174 return GSS_S_BAD_SIG;
177 /* Validate header integrity */
179 althdr = (unsigned char *)header->buffer.value + 16 + ec;
181 althdr = (unsigned char *)trailer->buffer.value + ec;
183 if (load_uint16_be(althdr) != TOK_TYPE_WRAP
184 || althdr[2] != ptr[2]
185 || althdr[3] != ptr[3]
186 || memcmp(althdr + 8, ptr + 8, 8) != 0) {
188 return GSS_S_BAD_SIG;
191 /* Verify checksum: note EC is checksum size here, not padding */
192 if (ec != krbTrailerLen)
195 /* Zero EC, RRC before computing checksum */
196 store_uint16_be(0, ptr + 4);
197 store_uint16_be(0, ptr + 6);
199 code = gssEapVerify(krbContext, ctx->checksumType, rrc,
200 &ctx->rfc3961Key, keyUsage,
201 iov, iov_count, &valid);
202 if (code != 0 || valid == FALSE) {
204 return GSS_S_BAD_SIG;
208 code = sequenceCheck(minor, &ctx->seqState, seqnum);
209 } else if (toktype == TOK_TYPE_MIC) {
210 if (load_uint16_be(ptr) != toktype)
216 seqnum = load_uint64_be(ptr + 8);
218 code = gssEapVerify(krbContext, ctx->checksumType, 0,
219 &ctx->rfc3961Key, keyUsage,
220 iov, iov_count, &valid);
221 if (code != 0 || valid == FALSE) {
223 return GSS_S_BAD_SIG;
225 code = sequenceCheck(minor, &ctx->seqState, seqnum);
226 } else if (toktype == TOK_TYPE_DELETE_CONTEXT) {
227 if (load_uint16_be(ptr) != TOK_TYPE_DELETE_CONTEXT)
236 if (conf_state != NULL)
237 *conf_state = conf_flag;
244 return GSS_S_DEFECTIVE_TOKEN;
248 rotateLeft(void *ptr, size_t bufsiz, size_t rc)
258 tbuf = GSSEAP_MALLOC(rc);
262 memcpy(tbuf, ptr, rc);
263 memmove(ptr, (char *)ptr + rc, bufsiz - rc);
264 memcpy((char *)ptr + bufsiz - rc, tbuf, rc);
271 * Split a STREAM | SIGN_DATA | DATA into
272 * HEADER | SIGN_DATA | DATA | PADDING | TRAILER
275 unwrapStream(OM_uint32 *minor,
278 gss_qop_t *qop_state,
279 gss_iov_buffer_desc *iov,
281 enum gss_eap_token_type toktype)
284 OM_uint32 code = 0, major = GSS_S_FAILURE;
285 krb5_context krbContext;
286 int conf_req_flag, toktype2;
288 gss_iov_buffer_desc *tiov = NULL;
289 gss_iov_buffer_t stream, data = NULL;
290 gss_iov_buffer_t theader, tdata = NULL, tpadding, ttrailer;
292 GSSEAP_KRB_INIT(&krbContext);
294 assert(toktype == TOK_TYPE_WRAP);
296 if (toktype != TOK_TYPE_WRAP) {
301 stream = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM);
302 assert(stream != NULL);
304 if (stream->buffer.length < 16) {
305 major = GSS_S_DEFECTIVE_TOKEN;
309 ptr = (unsigned char *)stream->buffer.value;
310 toktype2 = load_uint16_be(ptr);
313 tiov = (gss_iov_buffer_desc *)GSSEAP_CALLOC((size_t)iov_count + 2,
314 sizeof(gss_iov_buffer_desc));
321 theader = &tiov[i++];
322 theader->type = GSS_IOV_BUFFER_TYPE_HEADER;
323 theader->buffer.value = stream->buffer.value;
324 theader->buffer.length = 16;
326 /* n[SIGN_DATA] | DATA | m[SIGN_DATA] */
327 for (j = 0; j < iov_count; j++) {
328 OM_uint32 type = GSS_IOV_BUFFER_TYPE(iov[j].type);
330 if (type == GSS_IOV_BUFFER_TYPE_DATA) {
332 /* only a single DATA buffer can appear */
340 if (type == GSS_IOV_BUFFER_TYPE_DATA ||
341 type == GSS_IOV_BUFFER_TYPE_SIGN_ONLY)
346 /* a single DATA buffer must be present */
351 /* PADDING | TRAILER */
352 tpadding = &tiov[i++];
353 tpadding->type = GSS_IOV_BUFFER_TYPE_PADDING;
354 tpadding->buffer.length = 0;
355 tpadding->buffer.value = NULL;
357 ttrailer = &tiov[i++];
358 ttrailer->type = GSS_IOV_BUFFER_TYPE_TRAILER;
362 unsigned int krbHeaderLen = 0;
363 unsigned int krbTrailerLen = 0;
365 conf_req_flag = ((ptr[0] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
366 ec = conf_req_flag ? load_uint16_be(ptr + 2) : 0;
367 rrc = load_uint16_be(ptr + 4);
370 code = rotateLeft((unsigned char *)stream->buffer.value + 16,
371 stream->buffer.length - 16, rrc);
374 store_uint16_be(0, ptr + 4); /* set RRC to zero */
378 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
379 KRB5_CRYPTO_TYPE_HEADER, &krbHeaderLen);
382 theader->buffer.length += krbHeaderLen; /* length validated later */
385 /* no PADDING for CFX, EC is used instead */
386 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
388 ? KRB5_CRYPTO_TYPE_TRAILER
389 : KRB5_CRYPTO_TYPE_CHECKSUM,
394 ttrailer->buffer.length = ec + (conf_req_flag ? 16 : 0 /* E(Header) */) +
396 ttrailer->buffer.value = (unsigned char *)stream->buffer.value +
397 stream->buffer.length - ttrailer->buffer.length;
400 /* IOV: -----------0-------------+---1---+--2--+----------------3--------------*/
401 /* Old: GSS-Header | Conf | Data | Pad | */
402 /* CFX: GSS-Header | Kerb-Header | Data | | EC | E(Header) | Kerb-Trailer */
403 /* GSS: -------GSS-HEADER--------+-DATA--+-PAD-+----------GSS-TRAILER----------*/
405 /* validate lengths */
406 if (stream->buffer.length < theader->buffer.length +
407 tpadding->buffer.length +
408 ttrailer->buffer.length) {
409 code = KRB5_BAD_MSIZE;
410 major = GSS_S_DEFECTIVE_TOKEN;
415 tdata->buffer.length = stream->buffer.length - ttrailer->buffer.length -
416 tpadding->buffer.length - theader->buffer.length;
418 assert(data != NULL);
420 if (data->type & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
421 code = gssEapAllocIov(tdata, tdata->buffer.length);
425 memcpy(tdata->buffer.value,
426 (unsigned char *)stream->buffer.value + theader->buffer.length,
427 tdata->buffer.length);
429 tdata->buffer.value = (unsigned char *)stream->buffer.value +
430 theader->buffer.length;
433 assert(i <= iov_count + 2);
435 major = unwrapToken(&code, ctx, conf_state, qop_state,
437 if (major == GSS_S_COMPLETE) {
439 } else if (tdata->type & GSS_IOV_BUFFER_FLAG_ALLOCATED) {
442 gss_release_buffer(&tmp, &tdata->buffer);
443 tdata->type &= ~(GSS_IOV_BUFFER_FLAG_ALLOCATED);
456 gssEapUnwrapOrVerifyMIC(OM_uint32 *minor,
459 gss_qop_t *qop_state,
460 gss_iov_buffer_desc *iov,
462 enum gss_eap_token_type toktype)
466 if (ctx->encryptionType == ENCTYPE_NULL)
467 return GSS_S_UNAVAILABLE;
469 if (gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM) != NULL) {
470 major = unwrapStream(minor, ctx, conf_state, qop_state,
471 iov, iov_count, toktype);
473 major = unwrapToken(minor, ctx, conf_state, qop_state,
474 iov, iov_count, toktype);
481 gss_unwrap_iov(OM_uint32 *minor,
484 gss_qop_t *qop_state,
485 gss_iov_buffer_desc *iov,
488 if (!CTX_IS_ESTABLISHED(ctx))
489 return GSS_S_NO_CONTEXT;
491 return gssEapUnwrapOrVerifyMIC(minor, ctx, conf_state, qop_state,
492 iov, iov_count, TOK_TYPE_WRAP);