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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;
76 unsigned char acceptorFlag;
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 acceptorFlag = CTX_IS_INITIATOR(ctx) ? TOK_FLAG_SENDER_IS_ACCEPTOR : 0;
103 keyUsage = (toktype == TOK_TYPE_WRAP
104 ? (!CTX_IS_INITIATOR(ctx)
105 ? KEY_USAGE_INITIATOR_SEAL
106 : KEY_USAGE_ACCEPTOR_SEAL)
107 : (!CTX_IS_INITIATOR(ctx)
108 ? KEY_USAGE_INITIATOR_SIGN
109 : KEY_USAGE_ACCEPTOR_SIGN));
111 gssEapIovMessageLength(iov, iov_count, &dataLen, &assocDataLen);
113 ptr = (unsigned char *)header->buffer.value;
115 if (header->buffer.length < 16) {
117 return GSS_S_DEFECTIVE_TOKEN;
120 if ((ptr[2] & TOK_FLAG_SENDER_IS_ACCEPTOR) != acceptorFlag) {
121 return GSS_S_BAD_SIG;
124 if (ptr[2] & TOK_FLAG_ACCEPTOR_SUBKEY) {
125 return GSS_S_BAD_SIG;
128 if (toktype == TOK_TYPE_WRAP) {
129 unsigned int krbTrailerLen;
131 if (load_uint16_be(ptr) != TOK_TYPE_WRAP)
133 conf_flag = ((ptr[2] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
136 ec = load_uint16_be(ptr + 4);
137 rrc = load_uint16_be(ptr + 6);
138 seqnum = load_uint64_be(ptr + 8);
140 code = krb5_c_crypto_length(krbContext,
142 conf_flag ? KRB5_CRYPTO_TYPE_TRAILER :
143 KRB5_CRYPTO_TYPE_CHECKSUM,
147 return GSS_S_FAILURE;
151 if (trailer == NULL) {
152 size_t desired_rrc = krbTrailerLen;
155 desired_rrc += 16; /* E(Header) */
157 if ((ctx->gssFlags & GSS_C_DCE_STYLE) == 0)
161 /* According to MS, we only need to deal with a fixed RRC for DCE */
162 if (rrc != desired_rrc)
164 } else if (rrc != 0) {
169 unsigned char *althdr;
172 code = gssEapDecrypt(krbContext,
173 ((ctx->gssFlags & GSS_C_DCE_STYLE) != 0),
174 ec, rrc, &ctx->rfc3961Key,
175 keyUsage, 0, iov, iov_count);
178 return GSS_S_BAD_SIG;
181 /* Validate header integrity */
183 althdr = (unsigned char *)header->buffer.value + 16 + ec;
185 althdr = (unsigned char *)trailer->buffer.value + ec;
187 if (load_uint16_be(althdr) != TOK_TYPE_WRAP
188 || althdr[2] != ptr[2]
189 || althdr[3] != ptr[3]
190 || memcmp(althdr + 8, ptr + 8, 8) != 0) {
192 return GSS_S_BAD_SIG;
195 /* Verify checksum: note EC is checksum size here, not padding */
196 if (ec != krbTrailerLen)
199 /* Zero EC, RRC before computing checksum */
200 store_uint16_be(0, ptr + 4);
201 store_uint16_be(0, ptr + 6);
203 code = gssEapVerify(krbContext, 0, rrc,
204 &ctx->rfc3961Key, keyUsage,
205 iov, iov_count, &valid);
206 if (code != 0 || valid == FALSE) {
208 return GSS_S_BAD_SIG;
212 code = sequenceCheck(&ctx->seqState, seqnum);
213 } else if (toktype == TOK_TYPE_MIC) {
214 if (load_uint16_be(ptr) != TOK_TYPE_MIC)
220 seqnum = load_uint64_be(ptr + 8);
222 code = gssEapVerify(krbContext, 0, 0,
223 &ctx->rfc3961Key, keyUsage,
224 iov, iov_count, &valid);
225 if (code != 0 || valid == FALSE) {
227 return GSS_S_BAD_SIG;
229 code = sequenceCheck(&ctx->seqState, seqnum);
230 } else if (toktype == TOK_TYPE_DELETE_CONTEXT) {
231 if (load_uint16_be(ptr) != TOK_TYPE_DELETE_CONTEXT)
240 if (conf_state != NULL)
241 *conf_state = conf_flag;
248 return GSS_S_DEFECTIVE_TOKEN;
252 rotateLeft(void *ptr, size_t bufsiz, size_t rc)
262 tbuf = GSSEAP_MALLOC(rc);
266 memcpy(tbuf, ptr, rc);
267 memmove(ptr, (char *)ptr + rc, bufsiz - rc);
268 memcpy((char *)ptr + bufsiz - rc, tbuf, rc);
275 * Split a STREAM | SIGN_DATA | DATA into
276 * HEADER | SIGN_DATA | DATA | PADDING | TRAILER
279 unwrapStream(OM_uint32 *minor,
282 gss_qop_t *qop_state,
283 gss_iov_buffer_desc *iov,
285 enum gss_eap_token_type toktype)
288 OM_uint32 code = 0, major = GSS_S_FAILURE;
289 krb5_context krbContext;
290 int conf_req_flag, toktype2;
292 gss_iov_buffer_desc *tiov = NULL;
293 gss_iov_buffer_t stream, data = NULL;
294 gss_iov_buffer_t theader, tdata = NULL, tpadding, ttrailer;
296 GSSEAP_KRB_INIT(&krbContext);
298 assert(toktype == TOK_TYPE_WRAP);
300 if (toktype != TOK_TYPE_WRAP || (ctx->gssFlags & GSS_C_DCE_STYLE)) {
305 stream = gssEapLocateIov(iov, iov_count, GSS_IOV_BUFFER_TYPE_STREAM);
306 assert(stream != NULL);
308 if (stream->buffer.length < 16) {
309 major = GSS_S_DEFECTIVE_TOKEN;
313 ptr = (unsigned char *)stream->buffer.value;
314 toktype2 = load_uint16_be(ptr);
317 tiov = (gss_iov_buffer_desc *)GSSEAP_CALLOC((size_t)iov_count + 2,
318 sizeof(gss_iov_buffer_desc));
325 theader = &tiov[i++];
326 theader->type = GSS_IOV_BUFFER_TYPE_HEADER;
327 theader->buffer.value = stream->buffer.value;
328 theader->buffer.length = 16;
330 /* n[SIGN_DATA] | DATA | m[SIGN_DATA] */
331 for (j = 0; j < iov_count; j++) {
332 OM_uint32 type = GSS_IOV_BUFFER_TYPE(iov[j].type);
334 if (type == GSS_IOV_BUFFER_TYPE_DATA) {
336 /* only a single DATA buffer can appear */
344 if (type == GSS_IOV_BUFFER_TYPE_DATA ||
345 type == GSS_IOV_BUFFER_TYPE_SIGN_ONLY)
350 /* a single DATA buffer must be present */
355 /* PADDING | TRAILER */
356 tpadding = &tiov[i++];
357 tpadding->type = GSS_IOV_BUFFER_TYPE_PADDING;
358 tpadding->buffer.length = 0;
359 tpadding->buffer.value = NULL;
361 ttrailer = &tiov[i++];
362 ttrailer->type = GSS_IOV_BUFFER_TYPE_TRAILER;
366 unsigned int krbHeaderLen = 0;
367 unsigned int krbTrailerLen = 0;
369 conf_req_flag = ((ptr[0] & TOK_FLAG_WRAP_CONFIDENTIAL) != 0);
370 ec = conf_req_flag ? load_uint16_be(ptr + 2) : 0;
371 rrc = load_uint16_be(ptr + 4);
374 code = rotateLeft((unsigned char *)stream->buffer.value + 16,
375 stream->buffer.length - 16, rrc);
378 store_uint16_be(0, ptr + 4); /* set RRC to zero */
382 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
383 KRB5_CRYPTO_TYPE_HEADER, &krbHeaderLen);
386 theader->buffer.length += krbHeaderLen; /* length validated later */
389 /* no PADDING for CFX, EC is used instead */
390 code = krb5_c_crypto_length(krbContext, ctx->encryptionType,
392 ? KRB5_CRYPTO_TYPE_TRAILER
393 : KRB5_CRYPTO_TYPE_CHECKSUM,
398 ttrailer->buffer.length = ec + (conf_req_flag ? 16 : 0 /* E(Header) */) +
400 ttrailer->buffer.value = (unsigned char *)stream->buffer.value +
401 stream->buffer.length - ttrailer->buffer.length;
404 /* IOV: -----------0-------------+---1---+--2--+----------------3--------------*/
405 /* Old: GSS-Header | Conf | Data | Pad | */
406 /* CFX: GSS-Header | Kerb-Header | Data | | EC | E(Header) | Kerb-Trailer */
407 /* GSS: -------GSS-HEADER--------+-DATA--+-PAD-+----------GSS-TRAILER----------*/
409 /* validate lengths */
410 if (stream->buffer.length < theader->buffer.length +
411 tpadding->buffer.length +
412 ttrailer->buffer.length) {
413 code = KRB5_BAD_MSIZE;
414 major = GSS_S_DEFECTIVE_TOKEN;
419 tdata->buffer.length = stream->buffer.length - ttrailer->buffer.length -
420 tpadding->buffer.length - theader->buffer.length;
422 assert(data != NULL);
424 if (data->type & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
425 code = gssEapAllocIov(tdata, tdata->buffer.length);
429 memcpy(tdata->buffer.value,
430 (unsigned char *)stream->buffer.value + theader->buffer.length,
431 tdata->buffer.length);
433 tdata->buffer.value = (unsigned char *)stream->buffer.value +
434 theader->buffer.length;
437 assert(i <= iov_count + 2);
439 major = unwrapToken(&code, ctx, conf_state, qop_state,
441 if (major == GSS_S_COMPLETE) {
443 } else if (tdata->type & GSS_IOV_BUFFER_FLAG_ALLOCATED) {
446 gss_release_buffer(&tmp, &tdata->buffer);
447 tdata->type &= ~(GSS_IOV_BUFFER_FLAG_ALLOCATED);
460 gssEapUnwrapOrVerifyMIC(OM_uint32 *minor,
463 gss_qop_t *qop_state,
464 gss_iov_buffer_desc *iov,
466 enum gss_eap_token_type toktype)
470 if (!CTX_IS_ESTABLISHED(ctx))
471 return GSS_S_NO_CONTEXT;
473 if (ctx->encryptionType == ENCTYPE_NULL)
474 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,
495 return gssEapUnwrapOrVerifyMIC(minor, ctx, conf_state, qop_state,
496 iov, iov_count, TOK_TYPE_WRAP);