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37#include <crypto/algapi.h>
38#include <crypto/hash.h>
39#include <crypto/skcipher.h>
40#include <linux/err.h>
41#include <linux/types.h>
42#include <linux/mm.h>
43#include <linux/scatterlist.h>
44#include <linux/highmem.h>
45#include <linux/pagemap.h>
46#include <linux/random.h>
47#include <linux/sunrpc/gss_krb5.h>
48#include <linux/sunrpc/xdr.h>
49
50#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
51# define RPCDBG_FACILITY RPCDBG_AUTH
52#endif
53
54u32
55krb5_encrypt(
56 struct crypto_skcipher *tfm,
57 void * iv,
58 void * in,
59 void * out,
60 int length)
61{
62 u32 ret = -EINVAL;
63 struct scatterlist sg[1];
64 u8 local_iv[GSS_KRB5_MAX_BLOCKSIZE] = {0};
65 SKCIPHER_REQUEST_ON_STACK(req, tfm);
66
67 if (length % crypto_skcipher_blocksize(tfm) != 0)
68 goto out;
69
70 if (crypto_skcipher_ivsize(tfm) > GSS_KRB5_MAX_BLOCKSIZE) {
71 dprintk("RPC: gss_k5encrypt: tfm iv size too large %d\n",
72 crypto_skcipher_ivsize(tfm));
73 goto out;
74 }
75
76 if (iv)
77 memcpy(local_iv, iv, crypto_skcipher_ivsize(tfm));
78
79 memcpy(out, in, length);
80 sg_init_one(sg, out, length);
81
82 skcipher_request_set_tfm(req, tfm);
83 skcipher_request_set_callback(req, 0, NULL, NULL);
84 skcipher_request_set_crypt(req, sg, sg, length, local_iv);
85
86 ret = crypto_skcipher_encrypt(req);
87 skcipher_request_zero(req);
88out:
89 dprintk("RPC: krb5_encrypt returns %d\n", ret);
90 return ret;
91}
92
93u32
94krb5_decrypt(
95 struct crypto_skcipher *tfm,
96 void * iv,
97 void * in,
98 void * out,
99 int length)
100{
101 u32 ret = -EINVAL;
102 struct scatterlist sg[1];
103 u8 local_iv[GSS_KRB5_MAX_BLOCKSIZE] = {0};
104 SKCIPHER_REQUEST_ON_STACK(req, tfm);
105
106 if (length % crypto_skcipher_blocksize(tfm) != 0)
107 goto out;
108
109 if (crypto_skcipher_ivsize(tfm) > GSS_KRB5_MAX_BLOCKSIZE) {
110 dprintk("RPC: gss_k5decrypt: tfm iv size too large %d\n",
111 crypto_skcipher_ivsize(tfm));
112 goto out;
113 }
114 if (iv)
115 memcpy(local_iv,iv, crypto_skcipher_ivsize(tfm));
116
117 memcpy(out, in, length);
118 sg_init_one(sg, out, length);
119
120 skcipher_request_set_tfm(req, tfm);
121 skcipher_request_set_callback(req, 0, NULL, NULL);
122 skcipher_request_set_crypt(req, sg, sg, length, local_iv);
123
124 ret = crypto_skcipher_decrypt(req);
125 skcipher_request_zero(req);
126out:
127 dprintk("RPC: gss_k5decrypt returns %d\n",ret);
128 return ret;
129}
130
131static int
132checksummer(struct scatterlist *sg, void *data)
133{
134 struct ahash_request *req = data;
135
136 ahash_request_set_crypt(req, sg, NULL, sg->length);
137
138 return crypto_ahash_update(req);
139}
140
141static int
142arcfour_hmac_md5_usage_to_salt(unsigned int usage, u8 salt[4])
143{
144 unsigned int ms_usage;
145
146 switch (usage) {
147 case KG_USAGE_SIGN:
148 ms_usage = 15;
149 break;
150 case KG_USAGE_SEAL:
151 ms_usage = 13;
152 break;
153 default:
154 return -EINVAL;
155 }
156 salt[0] = (ms_usage >> 0) & 0xff;
157 salt[1] = (ms_usage >> 8) & 0xff;
158 salt[2] = (ms_usage >> 16) & 0xff;
159 salt[3] = (ms_usage >> 24) & 0xff;
160
161 return 0;
162}
163
164static u32
165make_checksum_hmac_md5(struct krb5_ctx *kctx, char *header, int hdrlen,
166 struct xdr_buf *body, int body_offset, u8 *cksumkey,
167 unsigned int usage, struct xdr_netobj *cksumout)
168{
169 struct scatterlist sg[1];
170 int err = -1;
171 u8 *checksumdata;
172 u8 rc4salt[4];
173 struct crypto_ahash *md5;
174 struct crypto_ahash *hmac_md5;
175 struct ahash_request *req;
176
177 if (cksumkey == NULL)
178 return GSS_S_FAILURE;
179
180 if (cksumout->len < kctx->gk5e->cksumlength) {
181 dprintk("%s: checksum buffer length, %u, too small for %s\n",
182 __func__, cksumout->len, kctx->gk5e->name);
183 return GSS_S_FAILURE;
184 }
185
186 if (arcfour_hmac_md5_usage_to_salt(usage, rc4salt)) {
187 dprintk("%s: invalid usage value %u\n", __func__, usage);
188 return GSS_S_FAILURE;
189 }
190
191 checksumdata = kmalloc(GSS_KRB5_MAX_CKSUM_LEN, GFP_NOFS);
192 if (!checksumdata)
193 return GSS_S_FAILURE;
194
195 md5 = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
196 if (IS_ERR(md5))
197 goto out_free_cksum;
198
199 hmac_md5 = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0,
200 CRYPTO_ALG_ASYNC);
201 if (IS_ERR(hmac_md5))
202 goto out_free_md5;
203
204 req = ahash_request_alloc(md5, GFP_NOFS);
205 if (!req)
206 goto out_free_hmac_md5;
207
208 ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
209
210 err = crypto_ahash_init(req);
211 if (err)
212 goto out;
213 sg_init_one(sg, rc4salt, 4);
214 ahash_request_set_crypt(req, sg, NULL, 4);
215 err = crypto_ahash_update(req);
216 if (err)
217 goto out;
218
219 sg_init_one(sg, header, hdrlen);
220 ahash_request_set_crypt(req, sg, NULL, hdrlen);
221 err = crypto_ahash_update(req);
222 if (err)
223 goto out;
224 err = xdr_process_buf(body, body_offset, body->len - body_offset,
225 checksummer, req);
226 if (err)
227 goto out;
228 ahash_request_set_crypt(req, NULL, checksumdata, 0);
229 err = crypto_ahash_final(req);
230 if (err)
231 goto out;
232
233 ahash_request_free(req);
234 req = ahash_request_alloc(hmac_md5, GFP_NOFS);
235 if (!req)
236 goto out_free_hmac_md5;
237
238 ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
239
240 err = crypto_ahash_setkey(hmac_md5, cksumkey, kctx->gk5e->keylength);
241 if (err)
242 goto out;
243
244 sg_init_one(sg, checksumdata, crypto_ahash_digestsize(md5));
245 ahash_request_set_crypt(req, sg, checksumdata,
246 crypto_ahash_digestsize(md5));
247 err = crypto_ahash_digest(req);
248 if (err)
249 goto out;
250
251 memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
252 cksumout->len = kctx->gk5e->cksumlength;
253out:
254 ahash_request_free(req);
255out_free_hmac_md5:
256 crypto_free_ahash(hmac_md5);
257out_free_md5:
258 crypto_free_ahash(md5);
259out_free_cksum:
260 kfree(checksumdata);
261 return err ? GSS_S_FAILURE : 0;
262}
263
264
265
266
267
268
269u32
270make_checksum(struct krb5_ctx *kctx, char *header, int hdrlen,
271 struct xdr_buf *body, int body_offset, u8 *cksumkey,
272 unsigned int usage, struct xdr_netobj *cksumout)
273{
274 struct crypto_ahash *tfm;
275 struct ahash_request *req;
276 struct scatterlist sg[1];
277 int err = -1;
278 u8 *checksumdata;
279 unsigned int checksumlen;
280
281 if (kctx->gk5e->ctype == CKSUMTYPE_HMAC_MD5_ARCFOUR)
282 return make_checksum_hmac_md5(kctx, header, hdrlen,
283 body, body_offset,
284 cksumkey, usage, cksumout);
285
286 if (cksumout->len < kctx->gk5e->cksumlength) {
287 dprintk("%s: checksum buffer length, %u, too small for %s\n",
288 __func__, cksumout->len, kctx->gk5e->name);
289 return GSS_S_FAILURE;
290 }
291
292 checksumdata = kmalloc(GSS_KRB5_MAX_CKSUM_LEN, GFP_NOFS);
293 if (checksumdata == NULL)
294 return GSS_S_FAILURE;
295
296 tfm = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
297 if (IS_ERR(tfm))
298 goto out_free_cksum;
299
300 req = ahash_request_alloc(tfm, GFP_NOFS);
301 if (!req)
302 goto out_free_ahash;
303
304 ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
305
306 checksumlen = crypto_ahash_digestsize(tfm);
307
308 if (cksumkey != NULL) {
309 err = crypto_ahash_setkey(tfm, cksumkey,
310 kctx->gk5e->keylength);
311 if (err)
312 goto out;
313 }
314
315 err = crypto_ahash_init(req);
316 if (err)
317 goto out;
318 sg_init_one(sg, header, hdrlen);
319 ahash_request_set_crypt(req, sg, NULL, hdrlen);
320 err = crypto_ahash_update(req);
321 if (err)
322 goto out;
323 err = xdr_process_buf(body, body_offset, body->len - body_offset,
324 checksummer, req);
325 if (err)
326 goto out;
327 ahash_request_set_crypt(req, NULL, checksumdata, 0);
328 err = crypto_ahash_final(req);
329 if (err)
330 goto out;
331
332 switch (kctx->gk5e->ctype) {
333 case CKSUMTYPE_RSA_MD5:
334 err = kctx->gk5e->encrypt(kctx->seq, NULL, checksumdata,
335 checksumdata, checksumlen);
336 if (err)
337 goto out;
338 memcpy(cksumout->data,
339 checksumdata + checksumlen - kctx->gk5e->cksumlength,
340 kctx->gk5e->cksumlength);
341 break;
342 case CKSUMTYPE_HMAC_SHA1_DES3:
343 memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
344 break;
345 default:
346 BUG();
347 break;
348 }
349 cksumout->len = kctx->gk5e->cksumlength;
350out:
351 ahash_request_free(req);
352out_free_ahash:
353 crypto_free_ahash(tfm);
354out_free_cksum:
355 kfree(checksumdata);
356 return err ? GSS_S_FAILURE : 0;
357}
358
359
360
361
362
363
364
365
366u32
367make_checksum_v2(struct krb5_ctx *kctx, char *header, int hdrlen,
368 struct xdr_buf *body, int body_offset, u8 *cksumkey,
369 unsigned int usage, struct xdr_netobj *cksumout)
370{
371 struct crypto_ahash *tfm;
372 struct ahash_request *req;
373 struct scatterlist sg[1];
374 int err = -1;
375 u8 *checksumdata;
376 unsigned int checksumlen;
377
378 if (kctx->gk5e->keyed_cksum == 0) {
379 dprintk("%s: expected keyed hash for %s\n",
380 __func__, kctx->gk5e->name);
381 return GSS_S_FAILURE;
382 }
383 if (cksumkey == NULL) {
384 dprintk("%s: no key supplied for %s\n",
385 __func__, kctx->gk5e->name);
386 return GSS_S_FAILURE;
387 }
388
389 checksumdata = kmalloc(GSS_KRB5_MAX_CKSUM_LEN, GFP_NOFS);
390 if (!checksumdata)
391 return GSS_S_FAILURE;
392
393 tfm = crypto_alloc_ahash(kctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
394 if (IS_ERR(tfm))
395 goto out_free_cksum;
396 checksumlen = crypto_ahash_digestsize(tfm);
397
398 req = ahash_request_alloc(tfm, GFP_NOFS);
399 if (!req)
400 goto out_free_ahash;
401
402 ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
403
404 err = crypto_ahash_setkey(tfm, cksumkey, kctx->gk5e->keylength);
405 if (err)
406 goto out;
407
408 err = crypto_ahash_init(req);
409 if (err)
410 goto out;
411 err = xdr_process_buf(body, body_offset, body->len - body_offset,
412 checksummer, req);
413 if (err)
414 goto out;
415 if (header != NULL) {
416 sg_init_one(sg, header, hdrlen);
417 ahash_request_set_crypt(req, sg, NULL, hdrlen);
418 err = crypto_ahash_update(req);
419 if (err)
420 goto out;
421 }
422 ahash_request_set_crypt(req, NULL, checksumdata, 0);
423 err = crypto_ahash_final(req);
424 if (err)
425 goto out;
426
427 cksumout->len = kctx->gk5e->cksumlength;
428
429 switch (kctx->gk5e->ctype) {
430 case CKSUMTYPE_HMAC_SHA1_96_AES128:
431 case CKSUMTYPE_HMAC_SHA1_96_AES256:
432
433 memcpy(cksumout->data, checksumdata, kctx->gk5e->cksumlength);
434 break;
435 default:
436 BUG();
437 break;
438 }
439out:
440 ahash_request_free(req);
441out_free_ahash:
442 crypto_free_ahash(tfm);
443out_free_cksum:
444 kfree(checksumdata);
445 return err ? GSS_S_FAILURE : 0;
446}
447
448struct encryptor_desc {
449 u8 iv[GSS_KRB5_MAX_BLOCKSIZE];
450 struct skcipher_request *req;
451 int pos;
452 struct xdr_buf *outbuf;
453 struct page **pages;
454 struct scatterlist infrags[4];
455 struct scatterlist outfrags[4];
456 int fragno;
457 int fraglen;
458};
459
460static int
461encryptor(struct scatterlist *sg, void *data)
462{
463 struct encryptor_desc *desc = data;
464 struct xdr_buf *outbuf = desc->outbuf;
465 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(desc->req);
466 struct page *in_page;
467 int thislen = desc->fraglen + sg->length;
468 int fraglen, ret;
469 int page_pos;
470
471
472
473 BUG_ON(desc->fragno > 3);
474
475 page_pos = desc->pos - outbuf->head[0].iov_len;
476 if (page_pos >= 0 && page_pos < outbuf->page_len) {
477
478 int i = (page_pos + outbuf->page_base) >> PAGE_SHIFT;
479 in_page = desc->pages[i];
480 } else {
481 in_page = sg_page(sg);
482 }
483 sg_set_page(&desc->infrags[desc->fragno], in_page, sg->length,
484 sg->offset);
485 sg_set_page(&desc->outfrags[desc->fragno], sg_page(sg), sg->length,
486 sg->offset);
487 desc->fragno++;
488 desc->fraglen += sg->length;
489 desc->pos += sg->length;
490
491 fraglen = thislen & (crypto_skcipher_blocksize(tfm) - 1);
492 thislen -= fraglen;
493
494 if (thislen == 0)
495 return 0;
496
497 sg_mark_end(&desc->infrags[desc->fragno - 1]);
498 sg_mark_end(&desc->outfrags[desc->fragno - 1]);
499
500 skcipher_request_set_crypt(desc->req, desc->infrags, desc->outfrags,
501 thislen, desc->iv);
502
503 ret = crypto_skcipher_encrypt(desc->req);
504 if (ret)
505 return ret;
506
507 sg_init_table(desc->infrags, 4);
508 sg_init_table(desc->outfrags, 4);
509
510 if (fraglen) {
511 sg_set_page(&desc->outfrags[0], sg_page(sg), fraglen,
512 sg->offset + sg->length - fraglen);
513 desc->infrags[0] = desc->outfrags[0];
514 sg_assign_page(&desc->infrags[0], in_page);
515 desc->fragno = 1;
516 desc->fraglen = fraglen;
517 } else {
518 desc->fragno = 0;
519 desc->fraglen = 0;
520 }
521 return 0;
522}
523
524int
525gss_encrypt_xdr_buf(struct crypto_skcipher *tfm, struct xdr_buf *buf,
526 int offset, struct page **pages)
527{
528 int ret;
529 struct encryptor_desc desc;
530 SKCIPHER_REQUEST_ON_STACK(req, tfm);
531
532 BUG_ON((buf->len - offset) % crypto_skcipher_blocksize(tfm) != 0);
533
534 skcipher_request_set_tfm(req, tfm);
535 skcipher_request_set_callback(req, 0, NULL, NULL);
536
537 memset(desc.iv, 0, sizeof(desc.iv));
538 desc.req = req;
539 desc.pos = offset;
540 desc.outbuf = buf;
541 desc.pages = pages;
542 desc.fragno = 0;
543 desc.fraglen = 0;
544
545 sg_init_table(desc.infrags, 4);
546 sg_init_table(desc.outfrags, 4);
547
548 ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
549 skcipher_request_zero(req);
550 return ret;
551}
552
553struct decryptor_desc {
554 u8 iv[GSS_KRB5_MAX_BLOCKSIZE];
555 struct skcipher_request *req;
556 struct scatterlist frags[4];
557 int fragno;
558 int fraglen;
559};
560
561static int
562decryptor(struct scatterlist *sg, void *data)
563{
564 struct decryptor_desc *desc = data;
565 int thislen = desc->fraglen + sg->length;
566 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(desc->req);
567 int fraglen, ret;
568
569
570
571 BUG_ON(desc->fragno > 3);
572 sg_set_page(&desc->frags[desc->fragno], sg_page(sg), sg->length,
573 sg->offset);
574 desc->fragno++;
575 desc->fraglen += sg->length;
576
577 fraglen = thislen & (crypto_skcipher_blocksize(tfm) - 1);
578 thislen -= fraglen;
579
580 if (thislen == 0)
581 return 0;
582
583 sg_mark_end(&desc->frags[desc->fragno - 1]);
584
585 skcipher_request_set_crypt(desc->req, desc->frags, desc->frags,
586 thislen, desc->iv);
587
588 ret = crypto_skcipher_decrypt(desc->req);
589 if (ret)
590 return ret;
591
592 sg_init_table(desc->frags, 4);
593
594 if (fraglen) {
595 sg_set_page(&desc->frags[0], sg_page(sg), fraglen,
596 sg->offset + sg->length - fraglen);
597 desc->fragno = 1;
598 desc->fraglen = fraglen;
599 } else {
600 desc->fragno = 0;
601 desc->fraglen = 0;
602 }
603 return 0;
604}
605
606int
607gss_decrypt_xdr_buf(struct crypto_skcipher *tfm, struct xdr_buf *buf,
608 int offset)
609{
610 int ret;
611 struct decryptor_desc desc;
612 SKCIPHER_REQUEST_ON_STACK(req, tfm);
613
614
615 BUG_ON((buf->len - offset) % crypto_skcipher_blocksize(tfm) != 0);
616
617 skcipher_request_set_tfm(req, tfm);
618 skcipher_request_set_callback(req, 0, NULL, NULL);
619
620 memset(desc.iv, 0, sizeof(desc.iv));
621 desc.req = req;
622 desc.fragno = 0;
623 desc.fraglen = 0;
624
625 sg_init_table(desc.frags, 4);
626
627 ret = xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
628 skcipher_request_zero(req);
629 return ret;
630}
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649int
650xdr_extend_head(struct xdr_buf *buf, unsigned int base, unsigned int shiftlen)
651{
652 u8 *p;
653
654 if (shiftlen == 0)
655 return 0;
656
657 BUILD_BUG_ON(GSS_KRB5_MAX_SLACK_NEEDED > RPC_MAX_AUTH_SIZE);
658 BUG_ON(shiftlen > RPC_MAX_AUTH_SIZE);
659
660 p = buf->head[0].iov_base + base;
661
662 memmove(p + shiftlen, p, buf->head[0].iov_len - base);
663
664 buf->head[0].iov_len += shiftlen;
665 buf->len += shiftlen;
666
667 return 0;
668}
669
670static u32
671gss_krb5_cts_crypt(struct crypto_skcipher *cipher, struct xdr_buf *buf,
672 u32 offset, u8 *iv, struct page **pages, int encrypt)
673{
674 u32 ret;
675 struct scatterlist sg[1];
676 SKCIPHER_REQUEST_ON_STACK(req, cipher);
677 u8 *data;
678 struct page **save_pages;
679 u32 len = buf->len - offset;
680
681 if (len > GSS_KRB5_MAX_BLOCKSIZE * 2) {
682 WARN_ON(0);
683 return -ENOMEM;
684 }
685 data = kmalloc(GSS_KRB5_MAX_BLOCKSIZE * 2, GFP_NOFS);
686 if (!data)
687 return -ENOMEM;
688
689
690
691
692
693
694 save_pages = buf->pages;
695 if (encrypt)
696 buf->pages = pages;
697
698 ret = read_bytes_from_xdr_buf(buf, offset, data, len);
699 buf->pages = save_pages;
700 if (ret)
701 goto out;
702
703 sg_init_one(sg, data, len);
704
705 skcipher_request_set_tfm(req, cipher);
706 skcipher_request_set_callback(req, 0, NULL, NULL);
707 skcipher_request_set_crypt(req, sg, sg, len, iv);
708
709 if (encrypt)
710 ret = crypto_skcipher_encrypt(req);
711 else
712 ret = crypto_skcipher_decrypt(req);
713
714 skcipher_request_zero(req);
715
716 if (ret)
717 goto out;
718
719 ret = write_bytes_to_xdr_buf(buf, offset, data, len);
720
721out:
722 kfree(data);
723 return ret;
724}
725
726u32
727gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
728 struct xdr_buf *buf, struct page **pages)
729{
730 u32 err;
731 struct xdr_netobj hmac;
732 u8 *cksumkey;
733 u8 *ecptr;
734 struct crypto_skcipher *cipher, *aux_cipher;
735 int blocksize;
736 struct page **save_pages;
737 int nblocks, nbytes;
738 struct encryptor_desc desc;
739 u32 cbcbytes;
740 unsigned int usage;
741
742 if (kctx->initiate) {
743 cipher = kctx->initiator_enc;
744 aux_cipher = kctx->initiator_enc_aux;
745 cksumkey = kctx->initiator_integ;
746 usage = KG_USAGE_INITIATOR_SEAL;
747 } else {
748 cipher = kctx->acceptor_enc;
749 aux_cipher = kctx->acceptor_enc_aux;
750 cksumkey = kctx->acceptor_integ;
751 usage = KG_USAGE_ACCEPTOR_SEAL;
752 }
753 blocksize = crypto_skcipher_blocksize(cipher);
754
755
756 offset += GSS_KRB5_TOK_HDR_LEN;
757 if (xdr_extend_head(buf, offset, kctx->gk5e->conflen))
758 return GSS_S_FAILURE;
759 gss_krb5_make_confounder(buf->head[0].iov_base + offset, kctx->gk5e->conflen);
760 offset -= GSS_KRB5_TOK_HDR_LEN;
761
762 if (buf->tail[0].iov_base != NULL) {
763 ecptr = buf->tail[0].iov_base + buf->tail[0].iov_len;
764 } else {
765 buf->tail[0].iov_base = buf->head[0].iov_base
766 + buf->head[0].iov_len;
767 buf->tail[0].iov_len = 0;
768 ecptr = buf->tail[0].iov_base;
769 }
770
771
772 memcpy(ecptr, buf->head[0].iov_base + offset, GSS_KRB5_TOK_HDR_LEN);
773 buf->tail[0].iov_len += GSS_KRB5_TOK_HDR_LEN;
774 buf->len += GSS_KRB5_TOK_HDR_LEN;
775
776
777 hmac.len = GSS_KRB5_MAX_CKSUM_LEN;
778 hmac.data = buf->tail[0].iov_base + buf->tail[0].iov_len;
779
780
781
782
783
784
785
786
787 save_pages = buf->pages;
788 buf->pages = pages;
789
790 err = make_checksum_v2(kctx, NULL, 0, buf,
791 offset + GSS_KRB5_TOK_HDR_LEN,
792 cksumkey, usage, &hmac);
793 buf->pages = save_pages;
794 if (err)
795 return GSS_S_FAILURE;
796
797 nbytes = buf->len - offset - GSS_KRB5_TOK_HDR_LEN;
798 nblocks = (nbytes + blocksize - 1) / blocksize;
799 cbcbytes = 0;
800 if (nblocks > 2)
801 cbcbytes = (nblocks - 2) * blocksize;
802
803 memset(desc.iv, 0, sizeof(desc.iv));
804
805 if (cbcbytes) {
806 SKCIPHER_REQUEST_ON_STACK(req, aux_cipher);
807
808 desc.pos = offset + GSS_KRB5_TOK_HDR_LEN;
809 desc.fragno = 0;
810 desc.fraglen = 0;
811 desc.pages = pages;
812 desc.outbuf = buf;
813 desc.req = req;
814
815 skcipher_request_set_tfm(req, aux_cipher);
816 skcipher_request_set_callback(req, 0, NULL, NULL);
817
818 sg_init_table(desc.infrags, 4);
819 sg_init_table(desc.outfrags, 4);
820
821 err = xdr_process_buf(buf, offset + GSS_KRB5_TOK_HDR_LEN,
822 cbcbytes, encryptor, &desc);
823 skcipher_request_zero(req);
824 if (err)
825 goto out_err;
826 }
827
828
829 err = gss_krb5_cts_crypt(cipher, buf,
830 offset + GSS_KRB5_TOK_HDR_LEN + cbcbytes,
831 desc.iv, pages, 1);
832 if (err) {
833 err = GSS_S_FAILURE;
834 goto out_err;
835 }
836
837
838 buf->tail[0].iov_len += kctx->gk5e->cksumlength;
839 buf->len += kctx->gk5e->cksumlength;
840
841out_err:
842 if (err)
843 err = GSS_S_FAILURE;
844 return err;
845}
846
847u32
848gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
849 u32 *headskip, u32 *tailskip)
850{
851 struct xdr_buf subbuf;
852 u32 ret = 0;
853 u8 *cksum_key;
854 struct crypto_skcipher *cipher, *aux_cipher;
855 struct xdr_netobj our_hmac_obj;
856 u8 our_hmac[GSS_KRB5_MAX_CKSUM_LEN];
857 u8 pkt_hmac[GSS_KRB5_MAX_CKSUM_LEN];
858 int nblocks, blocksize, cbcbytes;
859 struct decryptor_desc desc;
860 unsigned int usage;
861
862 if (kctx->initiate) {
863 cipher = kctx->acceptor_enc;
864 aux_cipher = kctx->acceptor_enc_aux;
865 cksum_key = kctx->acceptor_integ;
866 usage = KG_USAGE_ACCEPTOR_SEAL;
867 } else {
868 cipher = kctx->initiator_enc;
869 aux_cipher = kctx->initiator_enc_aux;
870 cksum_key = kctx->initiator_integ;
871 usage = KG_USAGE_INITIATOR_SEAL;
872 }
873 blocksize = crypto_skcipher_blocksize(cipher);
874
875
876
877 xdr_buf_subsegment(buf, &subbuf, offset + GSS_KRB5_TOK_HDR_LEN,
878 (buf->len - offset - GSS_KRB5_TOK_HDR_LEN -
879 kctx->gk5e->cksumlength));
880
881 nblocks = (subbuf.len + blocksize - 1) / blocksize;
882
883 cbcbytes = 0;
884 if (nblocks > 2)
885 cbcbytes = (nblocks - 2) * blocksize;
886
887 memset(desc.iv, 0, sizeof(desc.iv));
888
889 if (cbcbytes) {
890 SKCIPHER_REQUEST_ON_STACK(req, aux_cipher);
891
892 desc.fragno = 0;
893 desc.fraglen = 0;
894 desc.req = req;
895
896 skcipher_request_set_tfm(req, aux_cipher);
897 skcipher_request_set_callback(req, 0, NULL, NULL);
898
899 sg_init_table(desc.frags, 4);
900
901 ret = xdr_process_buf(&subbuf, 0, cbcbytes, decryptor, &desc);
902 skcipher_request_zero(req);
903 if (ret)
904 goto out_err;
905 }
906
907
908 ret = gss_krb5_cts_crypt(cipher, &subbuf, cbcbytes, desc.iv, NULL, 0);
909 if (ret)
910 goto out_err;
911
912
913
914 our_hmac_obj.len = sizeof(our_hmac);
915 our_hmac_obj.data = our_hmac;
916
917 ret = make_checksum_v2(kctx, NULL, 0, &subbuf, 0,
918 cksum_key, usage, &our_hmac_obj);
919 if (ret)
920 goto out_err;
921
922
923 ret = read_bytes_from_xdr_buf(buf, buf->len - kctx->gk5e->cksumlength,
924 pkt_hmac, kctx->gk5e->cksumlength);
925 if (ret)
926 goto out_err;
927
928 if (crypto_memneq(pkt_hmac, our_hmac, kctx->gk5e->cksumlength) != 0) {
929 ret = GSS_S_BAD_SIG;
930 goto out_err;
931 }
932 *headskip = kctx->gk5e->conflen;
933 *tailskip = kctx->gk5e->cksumlength;
934out_err:
935 if (ret && ret != GSS_S_BAD_SIG)
936 ret = GSS_S_FAILURE;
937 return ret;
938}
939
940
941
942
943
944int
945krb5_rc4_setup_seq_key(struct krb5_ctx *kctx, struct crypto_skcipher *cipher,
946 unsigned char *cksum)
947{
948 struct crypto_shash *hmac;
949 struct shash_desc *desc;
950 u8 Kseq[GSS_KRB5_MAX_KEYLEN];
951 u32 zeroconstant = 0;
952 int err;
953
954 dprintk("%s: entered\n", __func__);
955
956 hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
957 if (IS_ERR(hmac)) {
958 dprintk("%s: error %ld, allocating hash '%s'\n",
959 __func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
960 return PTR_ERR(hmac);
961 }
962
963 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
964 GFP_NOFS);
965 if (!desc) {
966 dprintk("%s: failed to allocate shash descriptor for '%s'\n",
967 __func__, kctx->gk5e->cksum_name);
968 crypto_free_shash(hmac);
969 return -ENOMEM;
970 }
971
972 desc->tfm = hmac;
973 desc->flags = 0;
974
975
976 err = crypto_shash_setkey(hmac, kctx->Ksess, kctx->gk5e->keylength);
977 if (err)
978 goto out_err;
979
980 err = crypto_shash_digest(desc, (u8 *)&zeroconstant, 4, Kseq);
981 if (err)
982 goto out_err;
983
984
985 err = crypto_shash_setkey(hmac, Kseq, kctx->gk5e->keylength);
986 if (err)
987 goto out_err;
988
989 err = crypto_shash_digest(desc, cksum, 8, Kseq);
990 if (err)
991 goto out_err;
992
993 err = crypto_skcipher_setkey(cipher, Kseq, kctx->gk5e->keylength);
994 if (err)
995 goto out_err;
996
997 err = 0;
998
999out_err:
1000 kzfree(desc);
1001 crypto_free_shash(hmac);
1002 dprintk("%s: returning %d\n", __func__, err);
1003 return err;
1004}
1005
1006
1007
1008
1009
1010int
1011krb5_rc4_setup_enc_key(struct krb5_ctx *kctx, struct crypto_skcipher *cipher,
1012 s32 seqnum)
1013{
1014 struct crypto_shash *hmac;
1015 struct shash_desc *desc;
1016 u8 Kcrypt[GSS_KRB5_MAX_KEYLEN];
1017 u8 zeroconstant[4] = {0};
1018 u8 seqnumarray[4];
1019 int err, i;
1020
1021 dprintk("%s: entered, seqnum %u\n", __func__, seqnum);
1022
1023 hmac = crypto_alloc_shash(kctx->gk5e->cksum_name, 0, 0);
1024 if (IS_ERR(hmac)) {
1025 dprintk("%s: error %ld, allocating hash '%s'\n",
1026 __func__, PTR_ERR(hmac), kctx->gk5e->cksum_name);
1027 return PTR_ERR(hmac);
1028 }
1029
1030 desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(hmac),
1031 GFP_NOFS);
1032 if (!desc) {
1033 dprintk("%s: failed to allocate shash descriptor for '%s'\n",
1034 __func__, kctx->gk5e->cksum_name);
1035 crypto_free_shash(hmac);
1036 return -ENOMEM;
1037 }
1038
1039 desc->tfm = hmac;
1040 desc->flags = 0;
1041
1042
1043 for (i = 0; i < kctx->gk5e->keylength; i++)
1044 Kcrypt[i] = kctx->Ksess[i] ^ 0xf0;
1045
1046 err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
1047 if (err)
1048 goto out_err;
1049
1050 err = crypto_shash_digest(desc, zeroconstant, 4, Kcrypt);
1051 if (err)
1052 goto out_err;
1053
1054
1055 err = crypto_shash_setkey(hmac, Kcrypt, kctx->gk5e->keylength);
1056 if (err)
1057 goto out_err;
1058
1059 seqnumarray[0] = (unsigned char) ((seqnum >> 24) & 0xff);
1060 seqnumarray[1] = (unsigned char) ((seqnum >> 16) & 0xff);
1061 seqnumarray[2] = (unsigned char) ((seqnum >> 8) & 0xff);
1062 seqnumarray[3] = (unsigned char) ((seqnum >> 0) & 0xff);
1063
1064 err = crypto_shash_digest(desc, seqnumarray, 4, Kcrypt);
1065 if (err)
1066 goto out_err;
1067
1068 err = crypto_skcipher_setkey(cipher, Kcrypt, kctx->gk5e->keylength);
1069 if (err)
1070 goto out_err;
1071
1072 err = 0;
1073
1074out_err:
1075 kzfree(desc);
1076 crypto_free_shash(hmac);
1077 dprintk("%s: returning %d\n", __func__, err);
1078 return err;
1079}
1080
1081