1/* 2 * Neil Brown <neilb@cse.unsw.edu.au> 3 * J. Bruce Fields <bfields@umich.edu> 4 * Andy Adamson <andros@umich.edu> 5 * Dug Song <dugsong@monkey.org> 6 * 7 * RPCSEC_GSS server authentication. 8 * This implements RPCSEC_GSS as defined in rfc2203 (rpcsec_gss) and rfc2078 9 * (gssapi) 10 * 11 * The RPCSEC_GSS involves three stages: 12 * 1/ context creation 13 * 2/ data exchange 14 * 3/ context destruction 15 * 16 * Context creation is handled largely by upcalls to user-space. 17 * In particular, GSS_Accept_sec_context is handled by an upcall 18 * Data exchange is handled entirely within the kernel 19 * In particular, GSS_GetMIC, GSS_VerifyMIC, GSS_Seal, GSS_Unseal are in-kernel. 20 * Context destruction is handled in-kernel 21 * GSS_Delete_sec_context is in-kernel 22 * 23 * Context creation is initiated by a RPCSEC_GSS_INIT request arriving. 24 * The context handle and gss_token are used as a key into the rpcsec_init cache. 25 * The content of this cache includes some of the outputs of GSS_Accept_sec_context, 26 * being major_status, minor_status, context_handle, reply_token. 27 * These are sent back to the client. 28 * Sequence window management is handled by the kernel. The window size if currently 29 * a compile time constant. 30 * 31 * When user-space is happy that a context is established, it places an entry 32 * in the rpcsec_context cache. The key for this cache is the context_handle. 33 * The content includes: 34 * uid/gidlist - for determining access rights 35 * mechanism type 36 * mechanism specific information, such as a key 37 * 38 */ 39 40#include <linux/slab.h> 41#include <linux/types.h> 42#include <linux/module.h> 43#include <linux/pagemap.h> 44#include <linux/user_namespace.h> 45 46#include <linux/sunrpc/auth_gss.h> 47#include <linux/sunrpc/gss_err.h> 48#include <linux/sunrpc/svcauth.h> 49#include <linux/sunrpc/svcauth_gss.h> 50#include <linux/sunrpc/cache.h> 51#include "gss_rpc_upcall.h" 52 53 54#ifdef RPC_DEBUG 55# define RPCDBG_FACILITY RPCDBG_AUTH 56#endif 57 58/* The rpcsec_init cache is used for mapping RPCSEC_GSS_{,CONT_}INIT requests 59 * into replies. 60 * 61 * Key is context handle (\x if empty) and gss_token. 62 * Content is major_status minor_status (integers) context_handle, reply_token. 63 * 64 */ 65 66static int netobj_equal(struct xdr_netobj *a, struct xdr_netobj *b) 67{ 68 return a->len == b->len && 0 == memcmp(a->data, b->data, a->len); 69} 70 71#define RSI_HASHBITS 6 72#define RSI_HASHMAX (1<<RSI_HASHBITS) 73 74struct rsi { 75 struct cache_head h; 76 struct xdr_netobj in_handle, in_token; 77 struct xdr_netobj out_handle, out_token; 78 int major_status, minor_status; 79}; 80 81static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old); 82static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item); 83 84static void rsi_free(struct rsi *rsii) 85{ 86 kfree(rsii->in_handle.data); 87 kfree(rsii->in_token.data); 88 kfree(rsii->out_handle.data); 89 kfree(rsii->out_token.data); 90} 91 92static void rsi_put(struct kref *ref) 93{ 94 struct rsi *rsii = container_of(ref, struct rsi, h.ref); 95 rsi_free(rsii); 96 kfree(rsii); 97} 98 99static inline int rsi_hash(struct rsi *item) 100{ 101 return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS) 102 ^ hash_mem(item->in_token.data, item->in_token.len, RSI_HASHBITS); 103} 104 105static int rsi_match(struct cache_head *a, struct cache_head *b) 106{ 107 struct rsi *item = container_of(a, struct rsi, h); 108 struct rsi *tmp = container_of(b, struct rsi, h); 109 return netobj_equal(&item->in_handle, &tmp->in_handle) && 110 netobj_equal(&item->in_token, &tmp->in_token); 111} 112 113static int dup_to_netobj(struct xdr_netobj *dst, char *src, int len) 114{ 115 dst->len = len; 116 dst->data = (len ? kmemdup(src, len, GFP_KERNEL) : NULL); 117 if (len && !dst->data) 118 return -ENOMEM; 119 return 0; 120} 121 122static inline int dup_netobj(struct xdr_netobj *dst, struct xdr_netobj *src) 123{ 124 return dup_to_netobj(dst, src->data, src->len); 125} 126 127static void rsi_init(struct cache_head *cnew, struct cache_head *citem) 128{ 129 struct rsi *new = container_of(cnew, struct rsi, h); 130 struct rsi *item = container_of(citem, struct rsi, h); 131 132 new->out_handle.data = NULL; 133 new->out_handle.len = 0; 134 new->out_token.data = NULL; 135 new->out_token.len = 0; 136 new->in_handle.len = item->in_handle.len; 137 item->in_handle.len = 0; 138 new->in_token.len = item->in_token.len; 139 item->in_token.len = 0; 140 new->in_handle.data = item->in_handle.data; 141 item->in_handle.data = NULL; 142 new->in_token.data = item->in_token.data; 143 item->in_token.data = NULL; 144} 145 146static void update_rsi(struct cache_head *cnew, struct cache_head *citem) 147{ 148 struct rsi *new = container_of(cnew, struct rsi, h); 149 struct rsi *item = container_of(citem, struct rsi, h); 150 151 BUG_ON(new->out_handle.data || new->out_token.data); 152 new->out_handle.len = item->out_handle.len; 153 item->out_handle.len = 0; 154 new->out_token.len = item->out_token.len; 155 item->out_token.len = 0; 156 new->out_handle.data = item->out_handle.data; 157 item->out_handle.data = NULL; 158 new->out_token.data = item->out_token.data; 159 item->out_token.data = NULL; 160 161 new->major_status = item->major_status; 162 new->minor_status = item->minor_status; 163} 164 165static struct cache_head *rsi_alloc(void) 166{ 167 struct rsi *rsii = kmalloc(sizeof(*rsii), GFP_KERNEL); 168 if (rsii) 169 return &rsii->h; 170 else 171 return NULL; 172} 173 174static void rsi_request(struct cache_detail *cd, 175 struct cache_head *h, 176 char **bpp, int *blen) 177{ 178 struct rsi *rsii = container_of(h, struct rsi, h); 179 180 qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len); 181 qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len); 182 (*bpp)[-1] = '\n'; 183} 184 185static int rsi_parse(struct cache_detail *cd, 186 char *mesg, int mlen) 187{ 188 /* context token expiry major minor context token */ 189 char *buf = mesg; 190 char *ep; 191 int len; 192 struct rsi rsii, *rsip = NULL; 193 time_t expiry; 194 int status = -EINVAL; 195 196 memset(&rsii, 0, sizeof(rsii)); 197 /* handle */ 198 len = qword_get(&mesg, buf, mlen); 199 if (len < 0) 200 goto out; 201 status = -ENOMEM; 202 if (dup_to_netobj(&rsii.in_handle, buf, len)) 203 goto out; 204 205 /* token */ 206 len = qword_get(&mesg, buf, mlen); 207 status = -EINVAL; 208 if (len < 0) 209 goto out; 210 status = -ENOMEM; 211 if (dup_to_netobj(&rsii.in_token, buf, len)) 212 goto out; 213 214 rsip = rsi_lookup(cd, &rsii); 215 if (!rsip) 216 goto out; 217 218 rsii.h.flags = 0; 219 /* expiry */ 220 expiry = get_expiry(&mesg); 221 status = -EINVAL; 222 if (expiry == 0) 223 goto out; 224 225 /* major/minor */ 226 len = qword_get(&mesg, buf, mlen); 227 if (len <= 0) 228 goto out; 229 rsii.major_status = simple_strtoul(buf, &ep, 10); 230 if (*ep) 231 goto out; 232 len = qword_get(&mesg, buf, mlen); 233 if (len <= 0) 234 goto out; 235 rsii.minor_status = simple_strtoul(buf, &ep, 10); 236 if (*ep) 237 goto out; 238 239 /* out_handle */ 240 len = qword_get(&mesg, buf, mlen); 241 if (len < 0) 242 goto out; 243 status = -ENOMEM; 244 if (dup_to_netobj(&rsii.out_handle, buf, len)) 245 goto out; 246 247 /* out_token */ 248 len = qword_get(&mesg, buf, mlen); 249 status = -EINVAL; 250 if (len < 0) 251 goto out; 252 status = -ENOMEM; 253 if (dup_to_netobj(&rsii.out_token, buf, len)) 254 goto out; 255 rsii.h.expiry_time = expiry; 256 rsip = rsi_update(cd, &rsii, rsip); 257 status = 0; 258out: 259 rsi_free(&rsii); 260 if (rsip) 261 cache_put(&rsip->h, cd); 262 else 263 status = -ENOMEM; 264 return status; 265} 266 267static struct cache_detail rsi_cache_template = { 268 .owner = THIS_MODULE, 269 .hash_size = RSI_HASHMAX, 270 .name = "auth.rpcsec.init", 271 .cache_put = rsi_put, 272 .cache_request = rsi_request, 273 .cache_parse = rsi_parse, 274 .match = rsi_match, 275 .init = rsi_init, 276 .update = update_rsi, 277 .alloc = rsi_alloc, 278}; 279 280static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item) 281{ 282 struct cache_head *ch; 283 int hash = rsi_hash(item); 284 285 ch = sunrpc_cache_lookup(cd, &item->h, hash); 286 if (ch) 287 return container_of(ch, struct rsi, h); 288 else 289 return NULL; 290} 291 292static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old) 293{ 294 struct cache_head *ch; 295 int hash = rsi_hash(new); 296 297 ch = sunrpc_cache_update(cd, &new->h, 298 &old->h, hash); 299 if (ch) 300 return container_of(ch, struct rsi, h); 301 else 302 return NULL; 303} 304 305 306/* 307 * The rpcsec_context cache is used to store a context that is 308 * used in data exchange. 309 * The key is a context handle. The content is: 310 * uid, gidlist, mechanism, service-set, mech-specific-data 311 */ 312 313#define RSC_HASHBITS 10 314#define RSC_HASHMAX (1<<RSC_HASHBITS) 315 316#define GSS_SEQ_WIN 128 317 318struct gss_svc_seq_data { 319 /* highest seq number seen so far: */ 320 int sd_max; 321 /* for i such that sd_max-GSS_SEQ_WIN < i <= sd_max, the i-th bit of 322 * sd_win is nonzero iff sequence number i has been seen already: */ 323 unsigned long sd_win[GSS_SEQ_WIN/BITS_PER_LONG]; 324 spinlock_t sd_lock; 325}; 326 327struct rsc { 328 struct cache_head h; 329 struct xdr_netobj handle; 330 struct svc_cred cred; 331 struct gss_svc_seq_data seqdata; 332 struct gss_ctx *mechctx; 333}; 334 335static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old); 336static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item); 337 338static void rsc_free(struct rsc *rsci) 339{ 340 kfree(rsci->handle.data); 341 if (rsci->mechctx) 342 gss_delete_sec_context(&rsci->mechctx); 343 free_svc_cred(&rsci->cred); 344} 345 346static void rsc_put(struct kref *ref) 347{ 348 struct rsc *rsci = container_of(ref, struct rsc, h.ref); 349 350 rsc_free(rsci); 351 kfree(rsci); 352} 353 354static inline int 355rsc_hash(struct rsc *rsci) 356{ 357 return hash_mem(rsci->handle.data, rsci->handle.len, RSC_HASHBITS); 358} 359 360static int 361rsc_match(struct cache_head *a, struct cache_head *b) 362{ 363 struct rsc *new = container_of(a, struct rsc, h); 364 struct rsc *tmp = container_of(b, struct rsc, h); 365 366 return netobj_equal(&new->handle, &tmp->handle); 367} 368 369static void 370rsc_init(struct cache_head *cnew, struct cache_head *ctmp) 371{ 372 struct rsc *new = container_of(cnew, struct rsc, h); 373 struct rsc *tmp = container_of(ctmp, struct rsc, h); 374 375 new->handle.len = tmp->handle.len; 376 tmp->handle.len = 0; 377 new->handle.data = tmp->handle.data; 378 tmp->handle.data = NULL; 379 new->mechctx = NULL; 380 init_svc_cred(&new->cred); 381} 382 383static void 384update_rsc(struct cache_head *cnew, struct cache_head *ctmp) 385{ 386 struct rsc *new = container_of(cnew, struct rsc, h); 387 struct rsc *tmp = container_of(ctmp, struct rsc, h); 388 389 new->mechctx = tmp->mechctx; 390 tmp->mechctx = NULL; 391 memset(&new->seqdata, 0, sizeof(new->seqdata)); 392 spin_lock_init(&new->seqdata.sd_lock); 393 new->cred = tmp->cred; 394 init_svc_cred(&tmp->cred); 395} 396 397static struct cache_head * 398rsc_alloc(void) 399{ 400 struct rsc *rsci = kmalloc(sizeof(*rsci), GFP_KERNEL); 401 if (rsci) 402 return &rsci->h; 403 else 404 return NULL; 405} 406 407static int rsc_parse(struct cache_detail *cd, 408 char *mesg, int mlen) 409{ 410 /* contexthandle expiry [ uid gid N <n gids> mechname ...mechdata... ] */ 411 char *buf = mesg; 412 int id; 413 int len, rv; 414 struct rsc rsci, *rscp = NULL; 415 time_t expiry; 416 int status = -EINVAL; 417 struct gss_api_mech *gm = NULL; 418 419 memset(&rsci, 0, sizeof(rsci)); 420 /* context handle */ 421 len = qword_get(&mesg, buf, mlen); 422 if (len < 0) goto out; 423 status = -ENOMEM; 424 if (dup_to_netobj(&rsci.handle, buf, len)) 425 goto out; 426 427 rsci.h.flags = 0; 428 /* expiry */ 429 expiry = get_expiry(&mesg); 430 status = -EINVAL; 431 if (expiry == 0) 432 goto out; 433 434 rscp = rsc_lookup(cd, &rsci); 435 if (!rscp) 436 goto out; 437 438 /* uid, or NEGATIVE */ 439 rv = get_int(&mesg, &id); 440 if (rv == -EINVAL) 441 goto out; 442 if (rv == -ENOENT) 443 set_bit(CACHE_NEGATIVE, &rsci.h.flags); 444 else { 445 int N, i; 446 447 /* 448 * NOTE: we skip uid_valid()/gid_valid() checks here: 449 * instead, * -1 id's are later mapped to the 450 * (export-specific) anonymous id by nfsd_setuser. 451 * 452 * (But supplementary gid's get no such special 453 * treatment so are checked for validity here.) 454 */ 455 /* uid */ 456 rsci.cred.cr_uid = make_kuid(&init_user_ns, id); 457 458 /* gid */ 459 if (get_int(&mesg, &id)) 460 goto out; 461 rsci.cred.cr_gid = make_kgid(&init_user_ns, id); 462 463 /* number of additional gid's */ 464 if (get_int(&mesg, &N)) 465 goto out; 466 status = -ENOMEM; 467 rsci.cred.cr_group_info = groups_alloc(N); 468 if (rsci.cred.cr_group_info == NULL) 469 goto out; 470 471 /* gid's */ 472 status = -EINVAL; 473 for (i=0; i<N; i++) { 474 kgid_t kgid; 475 if (get_int(&mesg, &id)) 476 goto out; 477 kgid = make_kgid(&init_user_ns, id); 478 if (!gid_valid(kgid)) 479 goto out; 480 GROUP_AT(rsci.cred.cr_group_info, i) = kgid; 481 } 482 483 /* mech name */ 484 len = qword_get(&mesg, buf, mlen); 485 if (len < 0) 486 goto out; 487 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf); 488 status = -EOPNOTSUPP; 489 if (!gm) 490 goto out; 491 492 status = -EINVAL; 493 /* mech-specific data: */ 494 len = qword_get(&mesg, buf, mlen); 495 if (len < 0) 496 goto out; 497 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx, 498 NULL, GFP_KERNEL); 499 if (status) 500 goto out; 501 502 /* get client name */ 503 len = qword_get(&mesg, buf, mlen); 504 if (len > 0) { 505 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL); 506 if (!rsci.cred.cr_principal) { 507 status = -ENOMEM; 508 goto out; 509 } 510 } 511 512 } 513 rsci.h.expiry_time = expiry; 514 rscp = rsc_update(cd, &rsci, rscp); 515 status = 0; 516out: 517 rsc_free(&rsci); 518 if (rscp) 519 cache_put(&rscp->h, cd); 520 else 521 status = -ENOMEM; 522 return status; 523} 524 525static struct cache_detail rsc_cache_template = { 526 .owner = THIS_MODULE, 527 .hash_size = RSC_HASHMAX, 528 .name = "auth.rpcsec.context", 529 .cache_put = rsc_put, 530 .cache_parse = rsc_parse, 531 .match = rsc_match, 532 .init = rsc_init, 533 .update = update_rsc, 534 .alloc = rsc_alloc, 535}; 536 537static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item) 538{ 539 struct cache_head *ch; 540 int hash = rsc_hash(item); 541 542 ch = sunrpc_cache_lookup(cd, &item->h, hash); 543 if (ch) 544 return container_of(ch, struct rsc, h); 545 else 546 return NULL; 547} 548 549static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old) 550{ 551 struct cache_head *ch; 552 int hash = rsc_hash(new); 553 554 ch = sunrpc_cache_update(cd, &new->h, 555 &old->h, hash); 556 if (ch) 557 return container_of(ch, struct rsc, h); 558 else 559 return NULL; 560} 561 562 563static struct rsc * 564gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle) 565{ 566 struct rsc rsci; 567 struct rsc *found; 568 569 memset(&rsci, 0, sizeof(rsci)); 570 if (dup_to_netobj(&rsci.handle, handle->data, handle->len)) 571 return NULL; 572 found = rsc_lookup(cd, &rsci); 573 rsc_free(&rsci); 574 if (!found) 575 return NULL; 576 if (cache_check(cd, &found->h, NULL)) 577 return NULL; 578 return found; 579} 580 581/* Implements sequence number algorithm as specified in RFC 2203. */ 582static int 583gss_check_seq_num(struct rsc *rsci, int seq_num) 584{ 585 struct gss_svc_seq_data *sd = &rsci->seqdata; 586 587 spin_lock(&sd->sd_lock); 588 if (seq_num > sd->sd_max) { 589 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) { 590 memset(sd->sd_win,0,sizeof(sd->sd_win)); 591 sd->sd_max = seq_num; 592 } else while (sd->sd_max < seq_num) { 593 sd->sd_max++; 594 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win); 595 } 596 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win); 597 goto ok; 598 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) { 599 goto drop; 600 } 601 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */ 602 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win)) 603 goto drop; 604ok: 605 spin_unlock(&sd->sd_lock); 606 return 1; 607drop: 608 spin_unlock(&sd->sd_lock); 609 return 0; 610} 611 612static inline u32 round_up_to_quad(u32 i) 613{ 614 return (i + 3 ) & ~3; 615} 616 617static inline int 618svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o) 619{ 620 int l; 621 622 if (argv->iov_len < 4) 623 return -1; 624 o->len = svc_getnl(argv); 625 l = round_up_to_quad(o->len); 626 if (argv->iov_len < l) 627 return -1; 628 o->data = argv->iov_base; 629 argv->iov_base += l; 630 argv->iov_len -= l; 631 return 0; 632} 633 634static inline int 635svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o) 636{ 637 u8 *p; 638 639 if (resv->iov_len + 4 > PAGE_SIZE) 640 return -1; 641 svc_putnl(resv, o->len); 642 p = resv->iov_base + resv->iov_len; 643 resv->iov_len += round_up_to_quad(o->len); 644 if (resv->iov_len > PAGE_SIZE) 645 return -1; 646 memcpy(p, o->data, o->len); 647 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len); 648 return 0; 649} 650 651/* 652 * Verify the checksum on the header and return SVC_OK on success. 653 * Otherwise, return SVC_DROP (in the case of a bad sequence number) 654 * or return SVC_DENIED and indicate error in authp. 655 */ 656static int 657gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci, 658 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp) 659{ 660 struct gss_ctx *ctx_id = rsci->mechctx; 661 struct xdr_buf rpchdr; 662 struct xdr_netobj checksum; 663 u32 flavor = 0; 664 struct kvec *argv = &rqstp->rq_arg.head[0]; 665 struct kvec iov; 666 667 /* data to compute the checksum over: */ 668 iov.iov_base = rpcstart; 669 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart; 670 xdr_buf_from_iov(&iov, &rpchdr); 671 672 *authp = rpc_autherr_badverf; 673 if (argv->iov_len < 4) 674 return SVC_DENIED; 675 flavor = svc_getnl(argv); 676 if (flavor != RPC_AUTH_GSS) 677 return SVC_DENIED; 678 if (svc_safe_getnetobj(argv, &checksum)) 679 return SVC_DENIED; 680 681 if (rqstp->rq_deferred) /* skip verification of revisited request */ 682 return SVC_OK; 683 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) { 684 *authp = rpcsec_gsserr_credproblem; 685 return SVC_DENIED; 686 } 687 688 if (gc->gc_seq > MAXSEQ) { 689 dprintk("RPC: svcauth_gss: discarding request with " 690 "large sequence number %d\n", gc->gc_seq); 691 *authp = rpcsec_gsserr_ctxproblem; 692 return SVC_DENIED; 693 } 694 if (!gss_check_seq_num(rsci, gc->gc_seq)) { 695 dprintk("RPC: svcauth_gss: discarding request with " 696 "old sequence number %d\n", gc->gc_seq); 697 return SVC_DROP; 698 } 699 return SVC_OK; 700} 701 702static int 703gss_write_null_verf(struct svc_rqst *rqstp) 704{ 705 __be32 *p; 706 707 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL); 708 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len; 709 /* don't really need to check if head->iov_len > PAGE_SIZE ... */ 710 *p++ = 0; 711 if (!xdr_ressize_check(rqstp, p)) 712 return -1; 713 return 0; 714} 715 716static int 717gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq) 718{ 719 __be32 xdr_seq; 720 u32 maj_stat; 721 struct xdr_buf verf_data; 722 struct xdr_netobj mic; 723 __be32 *p; 724 struct kvec iov; 725 726 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS); 727 xdr_seq = htonl(seq); 728 729 iov.iov_base = &xdr_seq; 730 iov.iov_len = sizeof(xdr_seq); 731 xdr_buf_from_iov(&iov, &verf_data); 732 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len; 733 mic.data = (u8 *)(p + 1); 734 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic); 735 if (maj_stat != GSS_S_COMPLETE) 736 return -1; 737 *p++ = htonl(mic.len); 738 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len); 739 p += XDR_QUADLEN(mic.len); 740 if (!xdr_ressize_check(rqstp, p)) 741 return -1; 742 return 0; 743} 744 745struct gss_domain { 746 struct auth_domain h; 747 u32 pseudoflavor; 748}; 749 750static struct auth_domain * 751find_gss_auth_domain(struct gss_ctx *ctx, u32 svc) 752{ 753 char *name; 754 755 name = gss_service_to_auth_domain_name(ctx->mech_type, svc); 756 if (!name) 757 return NULL; 758 return auth_domain_find(name); 759} 760 761static struct auth_ops svcauthops_gss; 762 763u32 svcauth_gss_flavor(struct auth_domain *dom) 764{ 765 struct gss_domain *gd = container_of(dom, struct gss_domain, h); 766 767 return gd->pseudoflavor; 768} 769 770EXPORT_SYMBOL_GPL(svcauth_gss_flavor); 771 772int 773svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name) 774{ 775 struct gss_domain *new; 776 struct auth_domain *test; 777 int stat = -ENOMEM; 778 779 new = kmalloc(sizeof(*new), GFP_KERNEL); 780 if (!new) 781 goto out; 782 kref_init(&new->h.ref); 783 new->h.name = kstrdup(name, GFP_KERNEL); 784 if (!new->h.name) 785 goto out_free_dom; 786 new->h.flavour = &svcauthops_gss; 787 new->pseudoflavor = pseudoflavor; 788 789 stat = 0; 790 test = auth_domain_lookup(name, &new->h); 791 if (test != &new->h) { /* Duplicate registration */ 792 auth_domain_put(test); 793 kfree(new->h.name); 794 goto out_free_dom; 795 } 796 return 0; 797 798out_free_dom: 799 kfree(new); 800out: 801 return stat; 802} 803 804EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor); 805 806static inline int 807read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj) 808{ 809 __be32 raw; 810 int status; 811 812 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); 813 if (status) 814 return status; 815 *obj = ntohl(raw); 816 return 0; 817} 818 819/* It would be nice if this bit of code could be shared with the client. 820 * Obstacles: 821 * The client shouldn't malloc(), would have to pass in own memory. 822 * The server uses base of head iovec as read pointer, while the 823 * client uses separate pointer. */ 824static int 825unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx) 826{ 827 int stat = -EINVAL; 828 u32 integ_len, maj_stat; 829 struct xdr_netobj mic; 830 struct xdr_buf integ_buf; 831 832 /* Did we already verify the signature on the original pass through? */ 833 if (rqstp->rq_deferred) 834 return 0; 835 836 integ_len = svc_getnl(&buf->head[0]); 837 if (integ_len & 3) 838 return stat; 839 if (integ_len > buf->len) 840 return stat; 841 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) 842 BUG(); 843 /* copy out mic... */ 844 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len)) 845 BUG(); 846 if (mic.len > RPC_MAX_AUTH_SIZE) 847 return stat; 848 mic.data = kmalloc(mic.len, GFP_KERNEL); 849 if (!mic.data) 850 return stat; 851 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len)) 852 goto out; 853 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic); 854 if (maj_stat != GSS_S_COMPLETE) 855 goto out; 856 if (svc_getnl(&buf->head[0]) != seq) 857 goto out; 858 /* trim off the mic at the end before returning */ 859 xdr_buf_trim(buf, mic.len + 4); 860 stat = 0; 861out: 862 kfree(mic.data); 863 return stat; 864} 865 866static inline int 867total_buf_len(struct xdr_buf *buf) 868{ 869 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len; 870} 871 872static void 873fix_priv_head(struct xdr_buf *buf, int pad) 874{ 875 if (buf->page_len == 0) { 876 /* We need to adjust head and buf->len in tandem in this 877 * case to make svc_defer() work--it finds the original 878 * buffer start using buf->len - buf->head[0].iov_len. */ 879 buf->head[0].iov_len -= pad; 880 } 881} 882 883static int 884unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx) 885{ 886 u32 priv_len, maj_stat; 887 int pad, saved_len, remaining_len, offset; 888 889 rqstp->rq_splice_ok = false; 890 891 priv_len = svc_getnl(&buf->head[0]); 892 if (rqstp->rq_deferred) { 893 /* Already decrypted last time through! The sequence number 894 * check at out_seq is unnecessary but harmless: */ 895 goto out_seq; 896 } 897 /* buf->len is the number of bytes from the original start of the 898 * request to the end, where head[0].iov_len is just the bytes 899 * not yet read from the head, so these two values are different: */ 900 remaining_len = total_buf_len(buf); 901 if (priv_len > remaining_len) 902 return -EINVAL; 903 pad = remaining_len - priv_len; 904 buf->len -= pad; 905 fix_priv_head(buf, pad); 906 907 /* Maybe it would be better to give gss_unwrap a length parameter: */ 908 saved_len = buf->len; 909 buf->len = priv_len; 910 maj_stat = gss_unwrap(ctx, 0, buf); 911 pad = priv_len - buf->len; 912 buf->len = saved_len; 913 buf->len -= pad; 914 /* The upper layers assume the buffer is aligned on 4-byte boundaries. 915 * In the krb5p case, at least, the data ends up offset, so we need to 916 * move it around. */ 917 /* XXX: This is very inefficient. It would be better to either do 918 * this while we encrypt, or maybe in the receive code, if we can peak 919 * ahead and work out the service and mechanism there. */ 920 offset = buf->head[0].iov_len % 4; 921 if (offset) { 922 buf->buflen = RPCSVC_MAXPAYLOAD; 923 xdr_shift_buf(buf, offset); 924 fix_priv_head(buf, pad); 925 } 926 if (maj_stat != GSS_S_COMPLETE) 927 return -EINVAL; 928out_seq: 929 if (svc_getnl(&buf->head[0]) != seq) 930 return -EINVAL; 931 return 0; 932} 933 934struct gss_svc_data { 935 /* decoded gss client cred: */ 936 struct rpc_gss_wire_cred clcred; 937 /* save a pointer to the beginning of the encoded verifier, 938 * for use in encryption/checksumming in svcauth_gss_release: */ 939 __be32 *verf_start; 940 struct rsc *rsci; 941}; 942 943static int 944svcauth_gss_set_client(struct svc_rqst *rqstp) 945{ 946 struct gss_svc_data *svcdata = rqstp->rq_auth_data; 947 struct rsc *rsci = svcdata->rsci; 948 struct rpc_gss_wire_cred *gc = &svcdata->clcred; 949 int stat; 950 951 /* 952 * A gss export can be specified either by: 953 * export *(sec=krb5,rw) 954 * or by 955 * export gss/krb5(rw) 956 * The latter is deprecated; but for backwards compatibility reasons 957 * the nfsd code will still fall back on trying it if the former 958 * doesn't work; so we try to make both available to nfsd, below. 959 */ 960 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc); 961 if (rqstp->rq_gssclient == NULL) 962 return SVC_DENIED; 963 stat = svcauth_unix_set_client(rqstp); 964 if (stat == SVC_DROP || stat == SVC_CLOSE) 965 return stat; 966 return SVC_OK; 967} 968 969static inline int 970gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp, 971 struct xdr_netobj *out_handle, int *major_status) 972{ 973 struct rsc *rsci; 974 int rc; 975 976 if (*major_status != GSS_S_COMPLETE) 977 return gss_write_null_verf(rqstp); 978 rsci = gss_svc_searchbyctx(cd, out_handle); 979 if (rsci == NULL) { 980 *major_status = GSS_S_NO_CONTEXT; 981 return gss_write_null_verf(rqstp); 982 } 983 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN); 984 cache_put(&rsci->h, cd); 985 return rc; 986} 987 988static inline int 989gss_read_common_verf(struct rpc_gss_wire_cred *gc, 990 struct kvec *argv, __be32 *authp, 991 struct xdr_netobj *in_handle) 992{ 993 /* Read the verifier; should be NULL: */ 994 *authp = rpc_autherr_badverf; 995 if (argv->iov_len < 2 * 4) 996 return SVC_DENIED; 997 if (svc_getnl(argv) != RPC_AUTH_NULL) 998 return SVC_DENIED; 999 if (svc_getnl(argv) != 0) 1000 return SVC_DENIED; 1001 /* Martial context handle and token for upcall: */ 1002 *authp = rpc_autherr_badcred; 1003 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0) 1004 return SVC_DENIED; 1005 if (dup_netobj(in_handle, &gc->gc_ctx)) 1006 return SVC_CLOSE; 1007 *authp = rpc_autherr_badverf; 1008 1009 return 0; 1010} 1011 1012static inline int 1013gss_read_verf(struct rpc_gss_wire_cred *gc, 1014 struct kvec *argv, __be32 *authp, 1015 struct xdr_netobj *in_handle, 1016 struct xdr_netobj *in_token) 1017{ 1018 struct xdr_netobj tmpobj; 1019 int res; 1020 1021 res = gss_read_common_verf(gc, argv, authp, in_handle); 1022 if (res) 1023 return res; 1024 1025 if (svc_safe_getnetobj(argv, &tmpobj)) { 1026 kfree(in_handle->data); 1027 return SVC_DENIED; 1028 } 1029 if (dup_netobj(in_token, &tmpobj)) { 1030 kfree(in_handle->data); 1031 return SVC_CLOSE; 1032 } 1033 1034 return 0; 1035} 1036 1037/* Ok this is really heavily depending on a set of semantics in 1038 * how rqstp is set up by svc_recv and pages laid down by the 1039 * server when reading a request. We are basically guaranteed that 1040 * the token lays all down linearly across a set of pages, starting 1041 * at iov_base in rq_arg.head[0] which happens to be the first of a 1042 * set of pages stored in rq_pages[]. 1043 * rq_arg.head[0].iov_base will provide us the page_base to pass 1044 * to the upcall. 1045 */ 1046static inline int 1047gss_read_proxy_verf(struct svc_rqst *rqstp, 1048 struct rpc_gss_wire_cred *gc, __be32 *authp, 1049 struct xdr_netobj *in_handle, 1050 struct gssp_in_token *in_token) 1051{ 1052 struct kvec *argv = &rqstp->rq_arg.head[0]; 1053 u32 inlen; 1054 int res; 1055 1056 res = gss_read_common_verf(gc, argv, authp, in_handle); 1057 if (res) 1058 return res; 1059 1060 inlen = svc_getnl(argv); 1061 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len)) 1062 return SVC_DENIED; 1063 1064 in_token->pages = rqstp->rq_pages; 1065 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK; 1066 in_token->page_len = inlen; 1067 1068 return 0; 1069} 1070 1071static inline int 1072gss_write_resv(struct kvec *resv, size_t size_limit, 1073 struct xdr_netobj *out_handle, struct xdr_netobj *out_token, 1074 int major_status, int minor_status) 1075{ 1076 if (resv->iov_len + 4 > size_limit) 1077 return -1; 1078 svc_putnl(resv, RPC_SUCCESS); 1079 if (svc_safe_putnetobj(resv, out_handle)) 1080 return -1; 1081 if (resv->iov_len + 3 * 4 > size_limit) 1082 return -1; 1083 svc_putnl(resv, major_status); 1084 svc_putnl(resv, minor_status); 1085 svc_putnl(resv, GSS_SEQ_WIN); 1086 if (svc_safe_putnetobj(resv, out_token)) 1087 return -1; 1088 return 0; 1089} 1090 1091/* 1092 * Having read the cred already and found we're in the context 1093 * initiation case, read the verifier and initiate (or check the results 1094 * of) upcalls to userspace for help with context initiation. If 1095 * the upcall results are available, write the verifier and result. 1096 * Otherwise, drop the request pending an answer to the upcall. 1097 */ 1098static int svcauth_gss_legacy_init(struct svc_rqst *rqstp, 1099 struct rpc_gss_wire_cred *gc, __be32 *authp) 1100{ 1101 struct kvec *argv = &rqstp->rq_arg.head[0]; 1102 struct kvec *resv = &rqstp->rq_res.head[0]; 1103 struct rsi *rsip, rsikey; 1104 int ret; 1105 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1106 1107 memset(&rsikey, 0, sizeof(rsikey)); 1108 ret = gss_read_verf(gc, argv, authp, 1109 &rsikey.in_handle, &rsikey.in_token); 1110 if (ret) 1111 return ret; 1112 1113 /* Perform upcall, or find upcall result: */ 1114 rsip = rsi_lookup(sn->rsi_cache, &rsikey); 1115 rsi_free(&rsikey); 1116 if (!rsip) 1117 return SVC_CLOSE; 1118 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0) 1119 /* No upcall result: */ 1120 return SVC_CLOSE; 1121 1122 ret = SVC_CLOSE; 1123 /* Got an answer to the upcall; use it: */ 1124 if (gss_write_init_verf(sn->rsc_cache, rqstp, 1125 &rsip->out_handle, &rsip->major_status)) 1126 goto out; 1127 if (gss_write_resv(resv, PAGE_SIZE, 1128 &rsip->out_handle, &rsip->out_token, 1129 rsip->major_status, rsip->minor_status)) 1130 goto out; 1131 1132 ret = SVC_COMPLETE; 1133out: 1134 cache_put(&rsip->h, sn->rsi_cache); 1135 return ret; 1136} 1137 1138static int gss_proxy_save_rsc(struct cache_detail *cd, 1139 struct gssp_upcall_data *ud, 1140 uint64_t *handle) 1141{ 1142 struct rsc rsci, *rscp = NULL; 1143 static atomic64_t ctxhctr; 1144 long long ctxh; 1145 struct gss_api_mech *gm = NULL; 1146 time_t expiry; 1147 int status = -EINVAL; 1148 1149 memset(&rsci, 0, sizeof(rsci)); 1150 /* context handle */ 1151 status = -ENOMEM; 1152 /* the handle needs to be just a unique id, 1153 * use a static counter */ 1154 ctxh = atomic64_inc_return(&ctxhctr); 1155 1156 /* make a copy for the caller */ 1157 *handle = ctxh; 1158 1159 /* make a copy for the rsc cache */ 1160 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t))) 1161 goto out; 1162 rscp = rsc_lookup(cd, &rsci); 1163 if (!rscp) 1164 goto out; 1165 1166 /* creds */ 1167 if (!ud->found_creds) { 1168 /* userspace seem buggy, we should always get at least a 1169 * mapping to nobody */ 1170 dprintk("RPC: No creds found!\n"); 1171 goto out; 1172 } else { 1173 1174 /* steal creds */ 1175 rsci.cred = ud->creds; 1176 memset(&ud->creds, 0, sizeof(struct svc_cred)); 1177 1178 status = -EOPNOTSUPP; 1179 /* get mech handle from OID */ 1180 gm = gss_mech_get_by_OID(&ud->mech_oid); 1181 if (!gm) 1182 goto out; 1183 rsci.cred.cr_gss_mech = gm; 1184 1185 status = -EINVAL; 1186 /* mech-specific data: */ 1187 status = gss_import_sec_context(ud->out_handle.data, 1188 ud->out_handle.len, 1189 gm, &rsci.mechctx, 1190 &expiry, GFP_KERNEL); 1191 if (status) 1192 goto out; 1193 } 1194 1195 rsci.h.expiry_time = expiry; 1196 rscp = rsc_update(cd, &rsci, rscp); 1197 status = 0; 1198out: 1199 rsc_free(&rsci); 1200 if (rscp) 1201 cache_put(&rscp->h, cd); 1202 else 1203 status = -ENOMEM; 1204 return status; 1205} 1206 1207static int svcauth_gss_proxy_init(struct svc_rqst *rqstp, 1208 struct rpc_gss_wire_cred *gc, __be32 *authp) 1209{ 1210 struct kvec *resv = &rqstp->rq_res.head[0]; 1211 struct xdr_netobj cli_handle; 1212 struct gssp_upcall_data ud; 1213 uint64_t handle; 1214 int status; 1215 int ret; 1216 struct net *net = rqstp->rq_xprt->xpt_net; 1217 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1218 1219 memset(&ud, 0, sizeof(ud)); 1220 ret = gss_read_proxy_verf(rqstp, gc, authp, 1221 &ud.in_handle, &ud.in_token); 1222 if (ret) 1223 return ret; 1224 1225 ret = SVC_CLOSE; 1226 1227 /* Perform synchronous upcall to gss-proxy */ 1228 status = gssp_accept_sec_context_upcall(net, &ud); 1229 if (status) 1230 goto out; 1231 1232 dprintk("RPC: svcauth_gss: gss major status = %d\n", 1233 ud.major_status); 1234 1235 switch (ud.major_status) { 1236 case GSS_S_CONTINUE_NEEDED: 1237 cli_handle = ud.out_handle; 1238 break; 1239 case GSS_S_COMPLETE: 1240 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle); 1241 if (status) 1242 goto out; 1243 cli_handle.data = (u8 *)&handle; 1244 cli_handle.len = sizeof(handle); 1245 break; 1246 default: 1247 ret = SVC_CLOSE; 1248 goto out; 1249 } 1250 1251 /* Got an answer to the upcall; use it: */ 1252 if (gss_write_init_verf(sn->rsc_cache, rqstp, 1253 &cli_handle, &ud.major_status)) 1254 goto out; 1255 if (gss_write_resv(resv, PAGE_SIZE, 1256 &cli_handle, &ud.out_token, 1257 ud.major_status, ud.minor_status)) 1258 goto out; 1259 1260 ret = SVC_COMPLETE; 1261out: 1262 gssp_free_upcall_data(&ud); 1263 return ret; 1264} 1265 1266/* 1267 * Try to set the sn->use_gss_proxy variable to a new value. We only allow 1268 * it to be changed if it's currently undefined (-1). If it's any other value 1269 * then return -EBUSY unless the type wouldn't have changed anyway. 1270 */ 1271static int set_gss_proxy(struct net *net, int type) 1272{ 1273 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1274 int ret; 1275 1276 WARN_ON_ONCE(type != 0 && type != 1); 1277 ret = cmpxchg(&sn->use_gss_proxy, -1, type); 1278 if (ret != -1 && ret != type) 1279 return -EBUSY; 1280 return 0; 1281} 1282 1283static bool use_gss_proxy(struct net *net) 1284{ 1285 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1286 1287 /* If use_gss_proxy is still undefined, then try to disable it */ 1288 if (sn->use_gss_proxy == -1) 1289 set_gss_proxy(net, 0); 1290 return sn->use_gss_proxy; 1291} 1292 1293#ifdef CONFIG_PROC_FS 1294 1295static ssize_t write_gssp(struct file *file, const char __user *buf, 1296 size_t count, loff_t *ppos) 1297{ 1298 struct net *net = PDE_DATA(file_inode(file)); 1299 char tbuf[20]; 1300 unsigned long i; 1301 int res; 1302 1303 if (*ppos || count > sizeof(tbuf)-1) 1304 return -EINVAL; 1305 if (copy_from_user(tbuf, buf, count)) 1306 return -EFAULT; 1307 1308 tbuf[count] = 0; 1309 res = kstrtoul(tbuf, 0, &i); 1310 if (res) 1311 return res; 1312 if (i != 1) 1313 return -EINVAL; 1314 res = set_gssp_clnt(net); 1315 if (res) 1316 return res; 1317 res = set_gss_proxy(net, 1); 1318 if (res) 1319 return res; 1320 return count; 1321} 1322 1323static ssize_t read_gssp(struct file *file, char __user *buf, 1324 size_t count, loff_t *ppos) 1325{ 1326 struct net *net = PDE_DATA(file_inode(file)); 1327 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1328 unsigned long p = *ppos; 1329 char tbuf[10]; 1330 size_t len; 1331 1332 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy); 1333 len = strlen(tbuf); 1334 if (p >= len) 1335 return 0; 1336 len -= p; 1337 if (len > count) 1338 len = count; 1339 if (copy_to_user(buf, (void *)(tbuf+p), len)) 1340 return -EFAULT; 1341 *ppos += len; 1342 return len; 1343} 1344 1345static const struct file_operations use_gss_proxy_ops = { 1346 .open = nonseekable_open, 1347 .write = write_gssp, 1348 .read = read_gssp, 1349}; 1350 1351static int create_use_gss_proxy_proc_entry(struct net *net) 1352{ 1353 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1354 struct proc_dir_entry **p = &sn->use_gssp_proc; 1355 1356 sn->use_gss_proxy = -1; 1357 *p = proc_create_data("use-gss-proxy", S_IFREG|S_IRUSR|S_IWUSR, 1358 sn->proc_net_rpc, 1359 &use_gss_proxy_ops, net); 1360 if (!*p) 1361 return -ENOMEM; 1362 init_gssp_clnt(sn); 1363 return 0; 1364} 1365 1366static void destroy_use_gss_proxy_proc_entry(struct net *net) 1367{ 1368 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1369 1370 if (sn->use_gssp_proc) { 1371 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc); 1372 clear_gssp_clnt(sn); 1373 } 1374} 1375#else /* CONFIG_PROC_FS */ 1376 1377static int create_use_gss_proxy_proc_entry(struct net *net) 1378{ 1379 return 0; 1380} 1381 1382static void destroy_use_gss_proxy_proc_entry(struct net *net) {} 1383 1384#endif /* CONFIG_PROC_FS */ 1385 1386/* 1387 * Accept an rpcsec packet. 1388 * If context establishment, punt to user space 1389 * If data exchange, verify/decrypt 1390 * If context destruction, handle here 1391 * In the context establishment and destruction case we encode 1392 * response here and return SVC_COMPLETE. 1393 */ 1394static int 1395svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp) 1396{ 1397 struct kvec *argv = &rqstp->rq_arg.head[0]; 1398 struct kvec *resv = &rqstp->rq_res.head[0]; 1399 u32 crlen; 1400 struct gss_svc_data *svcdata = rqstp->rq_auth_data; 1401 struct rpc_gss_wire_cred *gc; 1402 struct rsc *rsci = NULL; 1403 __be32 *rpcstart; 1404 __be32 *reject_stat = resv->iov_base + resv->iov_len; 1405 int ret; 1406 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1407 1408 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n", 1409 argv->iov_len); 1410 1411 *authp = rpc_autherr_badcred; 1412 if (!svcdata) 1413 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL); 1414 if (!svcdata) 1415 goto auth_err; 1416 rqstp->rq_auth_data = svcdata; 1417 svcdata->verf_start = NULL; 1418 svcdata->rsci = NULL; 1419 gc = &svcdata->clcred; 1420 1421 /* start of rpc packet is 7 u32's back from here: 1422 * xid direction rpcversion prog vers proc flavour 1423 */ 1424 rpcstart = argv->iov_base; 1425 rpcstart -= 7; 1426 1427 /* credential is: 1428 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle 1429 * at least 5 u32s, and is preceded by length, so that makes 6. 1430 */ 1431 1432 if (argv->iov_len < 5 * 4) 1433 goto auth_err; 1434 crlen = svc_getnl(argv); 1435 if (svc_getnl(argv) != RPC_GSS_VERSION) 1436 goto auth_err; 1437 gc->gc_proc = svc_getnl(argv); 1438 gc->gc_seq = svc_getnl(argv); 1439 gc->gc_svc = svc_getnl(argv); 1440 if (svc_safe_getnetobj(argv, &gc->gc_ctx)) 1441 goto auth_err; 1442 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4) 1443 goto auth_err; 1444 1445 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0)) 1446 goto auth_err; 1447 1448 *authp = rpc_autherr_badverf; 1449 switch (gc->gc_proc) { 1450 case RPC_GSS_PROC_INIT: 1451 case RPC_GSS_PROC_CONTINUE_INIT: 1452 if (use_gss_proxy(SVC_NET(rqstp))) 1453 return svcauth_gss_proxy_init(rqstp, gc, authp); 1454 else 1455 return svcauth_gss_legacy_init(rqstp, gc, authp); 1456 case RPC_GSS_PROC_DATA: 1457 case RPC_GSS_PROC_DESTROY: 1458 /* Look up the context, and check the verifier: */ 1459 *authp = rpcsec_gsserr_credproblem; 1460 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx); 1461 if (!rsci) 1462 goto auth_err; 1463 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) { 1464 case SVC_OK: 1465 break; 1466 case SVC_DENIED: 1467 goto auth_err; 1468 case SVC_DROP: 1469 goto drop; 1470 } 1471 break; 1472 default: 1473 *authp = rpc_autherr_rejectedcred; 1474 goto auth_err; 1475 } 1476 1477 /* now act upon the command: */ 1478 switch (gc->gc_proc) { 1479 case RPC_GSS_PROC_DESTROY: 1480 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq)) 1481 goto auth_err; 1482 rsci->h.expiry_time = get_seconds(); 1483 set_bit(CACHE_NEGATIVE, &rsci->h.flags); 1484 if (resv->iov_len + 4 > PAGE_SIZE) 1485 goto drop; 1486 svc_putnl(resv, RPC_SUCCESS); 1487 goto complete; 1488 case RPC_GSS_PROC_DATA: 1489 *authp = rpcsec_gsserr_ctxproblem; 1490 svcdata->verf_start = resv->iov_base + resv->iov_len; 1491 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq)) 1492 goto auth_err; 1493 rqstp->rq_cred = rsci->cred; 1494 get_group_info(rsci->cred.cr_group_info); 1495 *authp = rpc_autherr_badcred; 1496 switch (gc->gc_svc) { 1497 case RPC_GSS_SVC_NONE: 1498 break; 1499 case RPC_GSS_SVC_INTEGRITY: 1500 /* placeholders for length and seq. number: */ 1501 svc_putnl(resv, 0); 1502 svc_putnl(resv, 0); 1503 if (unwrap_integ_data(rqstp, &rqstp->rq_arg, 1504 gc->gc_seq, rsci->mechctx)) 1505 goto garbage_args; 1506 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE; 1507 break; 1508 case RPC_GSS_SVC_PRIVACY: 1509 /* placeholders for length and seq. number: */ 1510 svc_putnl(resv, 0); 1511 svc_putnl(resv, 0); 1512 if (unwrap_priv_data(rqstp, &rqstp->rq_arg, 1513 gc->gc_seq, rsci->mechctx)) 1514 goto garbage_args; 1515 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2; 1516 break; 1517 default: 1518 goto auth_err; 1519 } 1520 svcdata->rsci = rsci; 1521 cache_get(&rsci->h); 1522 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor( 1523 rsci->mechctx->mech_type, 1524 GSS_C_QOP_DEFAULT, 1525 gc->gc_svc); 1526 ret = SVC_OK; 1527 goto out; 1528 } 1529garbage_args: 1530 ret = SVC_GARBAGE; 1531 goto out; 1532auth_err: 1533 /* Restore write pointer to its original value: */ 1534 xdr_ressize_check(rqstp, reject_stat); 1535 ret = SVC_DENIED; 1536 goto out; 1537complete: 1538 ret = SVC_COMPLETE; 1539 goto out; 1540drop: 1541 ret = SVC_DROP; 1542out: 1543 if (rsci) 1544 cache_put(&rsci->h, sn->rsc_cache); 1545 return ret; 1546} 1547 1548static __be32 * 1549svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd) 1550{ 1551 __be32 *p; 1552 u32 verf_len; 1553 1554 p = gsd->verf_start; 1555 gsd->verf_start = NULL; 1556 1557 /* If the reply stat is nonzero, don't wrap: */ 1558 if (*(p-1) != rpc_success) 1559 return NULL; 1560 /* Skip the verifier: */ 1561 p += 1; 1562 verf_len = ntohl(*p++); 1563 p += XDR_QUADLEN(verf_len); 1564 /* move accept_stat to right place: */ 1565 memcpy(p, p + 2, 4); 1566 /* Also don't wrap if the accept stat is nonzero: */ 1567 if (*p != rpc_success) { 1568 resbuf->head[0].iov_len -= 2 * 4; 1569 return NULL; 1570 } 1571 p++; 1572 return p; 1573} 1574 1575static inline int 1576svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp) 1577{ 1578 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1579 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1580 struct xdr_buf *resbuf = &rqstp->rq_res; 1581 struct xdr_buf integ_buf; 1582 struct xdr_netobj mic; 1583 struct kvec *resv; 1584 __be32 *p; 1585 int integ_offset, integ_len; 1586 int stat = -EINVAL; 1587 1588 p = svcauth_gss_prepare_to_wrap(resbuf, gsd); 1589 if (p == NULL) 1590 goto out; 1591 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base; 1592 integ_len = resbuf->len - integ_offset; 1593 BUG_ON(integ_len % 4); 1594 *p++ = htonl(integ_len); 1595 *p++ = htonl(gc->gc_seq); 1596 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) 1597 BUG(); 1598 if (resbuf->tail[0].iov_base == NULL) { 1599 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1600 goto out_err; 1601 resbuf->tail[0].iov_base = resbuf->head[0].iov_base 1602 + resbuf->head[0].iov_len; 1603 resbuf->tail[0].iov_len = 0; 1604 } 1605 resv = &resbuf->tail[0]; 1606 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4; 1607 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic)) 1608 goto out_err; 1609 svc_putnl(resv, mic.len); 1610 memset(mic.data + mic.len, 0, 1611 round_up_to_quad(mic.len) - mic.len); 1612 resv->iov_len += XDR_QUADLEN(mic.len) << 2; 1613 /* not strictly required: */ 1614 resbuf->len += XDR_QUADLEN(mic.len) << 2; 1615 BUG_ON(resv->iov_len > PAGE_SIZE); 1616out: 1617 stat = 0; 1618out_err: 1619 return stat; 1620} 1621 1622static inline int 1623svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp) 1624{ 1625 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1626 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1627 struct xdr_buf *resbuf = &rqstp->rq_res; 1628 struct page **inpages = NULL; 1629 __be32 *p, *len; 1630 int offset; 1631 int pad; 1632 1633 p = svcauth_gss_prepare_to_wrap(resbuf, gsd); 1634 if (p == NULL) 1635 return 0; 1636 len = p++; 1637 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base; 1638 *p++ = htonl(gc->gc_seq); 1639 inpages = resbuf->pages; 1640 /* XXX: Would be better to write some xdr helper functions for 1641 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */ 1642 1643 /* 1644 * If there is currently tail data, make sure there is 1645 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in 1646 * the page, and move the current tail data such that 1647 * there is RPC_MAX_AUTH_SIZE slack space available in 1648 * both the head and tail. 1649 */ 1650 if (resbuf->tail[0].iov_base) { 1651 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base 1652 + PAGE_SIZE); 1653 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base); 1654 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len 1655 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1656 return -ENOMEM; 1657 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE, 1658 resbuf->tail[0].iov_base, 1659 resbuf->tail[0].iov_len); 1660 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE; 1661 } 1662 /* 1663 * If there is no current tail data, make sure there is 1664 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the 1665 * allotted page, and set up tail information such that there 1666 * is RPC_MAX_AUTH_SIZE slack space available in both the 1667 * head and tail. 1668 */ 1669 if (resbuf->tail[0].iov_base == NULL) { 1670 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1671 return -ENOMEM; 1672 resbuf->tail[0].iov_base = resbuf->head[0].iov_base 1673 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE; 1674 resbuf->tail[0].iov_len = 0; 1675 } 1676 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages)) 1677 return -ENOMEM; 1678 *len = htonl(resbuf->len - offset); 1679 pad = 3 - ((resbuf->len - offset - 1)&3); 1680 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len); 1681 memset(p, 0, pad); 1682 resbuf->tail[0].iov_len += pad; 1683 resbuf->len += pad; 1684 return 0; 1685} 1686 1687static int 1688svcauth_gss_release(struct svc_rqst *rqstp) 1689{ 1690 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1691 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1692 struct xdr_buf *resbuf = &rqstp->rq_res; 1693 int stat = -EINVAL; 1694 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1695 1696 if (gc->gc_proc != RPC_GSS_PROC_DATA) 1697 goto out; 1698 /* Release can be called twice, but we only wrap once. */ 1699 if (gsd->verf_start == NULL) 1700 goto out; 1701 /* normally not set till svc_send, but we need it here: */ 1702 /* XXX: what for? Do we mess it up the moment we call svc_putu32 1703 * or whatever? */ 1704 resbuf->len = total_buf_len(resbuf); 1705 switch (gc->gc_svc) { 1706 case RPC_GSS_SVC_NONE: 1707 break; 1708 case RPC_GSS_SVC_INTEGRITY: 1709 stat = svcauth_gss_wrap_resp_integ(rqstp); 1710 if (stat) 1711 goto out_err; 1712 break; 1713 case RPC_GSS_SVC_PRIVACY: 1714 stat = svcauth_gss_wrap_resp_priv(rqstp); 1715 if (stat) 1716 goto out_err; 1717 break; 1718 /* 1719 * For any other gc_svc value, svcauth_gss_accept() already set 1720 * the auth_error appropriately; just fall through: 1721 */ 1722 } 1723 1724out: 1725 stat = 0; 1726out_err: 1727 if (rqstp->rq_client) 1728 auth_domain_put(rqstp->rq_client); 1729 rqstp->rq_client = NULL; 1730 if (rqstp->rq_gssclient) 1731 auth_domain_put(rqstp->rq_gssclient); 1732 rqstp->rq_gssclient = NULL; 1733 if (rqstp->rq_cred.cr_group_info) 1734 put_group_info(rqstp->rq_cred.cr_group_info); 1735 rqstp->rq_cred.cr_group_info = NULL; 1736 if (gsd->rsci) 1737 cache_put(&gsd->rsci->h, sn->rsc_cache); 1738 gsd->rsci = NULL; 1739 1740 return stat; 1741} 1742 1743static void 1744svcauth_gss_domain_release(struct auth_domain *dom) 1745{ 1746 struct gss_domain *gd = container_of(dom, struct gss_domain, h); 1747 1748 kfree(dom->name); 1749 kfree(gd); 1750} 1751 1752static struct auth_ops svcauthops_gss = { 1753 .name = "rpcsec_gss", 1754 .owner = THIS_MODULE, 1755 .flavour = RPC_AUTH_GSS, 1756 .accept = svcauth_gss_accept, 1757 .release = svcauth_gss_release, 1758 .domain_release = svcauth_gss_domain_release, 1759 .set_client = svcauth_gss_set_client, 1760}; 1761 1762static int rsi_cache_create_net(struct net *net) 1763{ 1764 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1765 struct cache_detail *cd; 1766 int err; 1767 1768 cd = cache_create_net(&rsi_cache_template, net); 1769 if (IS_ERR(cd)) 1770 return PTR_ERR(cd); 1771 err = cache_register_net(cd, net); 1772 if (err) { 1773 cache_destroy_net(cd, net); 1774 return err; 1775 } 1776 sn->rsi_cache = cd; 1777 return 0; 1778} 1779 1780static void rsi_cache_destroy_net(struct net *net) 1781{ 1782 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1783 struct cache_detail *cd = sn->rsi_cache; 1784 1785 sn->rsi_cache = NULL; 1786 cache_purge(cd); 1787 cache_unregister_net(cd, net); 1788 cache_destroy_net(cd, net); 1789} 1790 1791static int rsc_cache_create_net(struct net *net) 1792{ 1793 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1794 struct cache_detail *cd; 1795 int err; 1796 1797 cd = cache_create_net(&rsc_cache_template, net); 1798 if (IS_ERR(cd)) 1799 return PTR_ERR(cd); 1800 err = cache_register_net(cd, net); 1801 if (err) { 1802 cache_destroy_net(cd, net); 1803 return err; 1804 } 1805 sn->rsc_cache = cd; 1806 return 0; 1807} 1808 1809static void rsc_cache_destroy_net(struct net *net) 1810{ 1811 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1812 struct cache_detail *cd = sn->rsc_cache; 1813 1814 sn->rsc_cache = NULL; 1815 cache_purge(cd); 1816 cache_unregister_net(cd, net); 1817 cache_destroy_net(cd, net); 1818} 1819 1820int 1821gss_svc_init_net(struct net *net) 1822{ 1823 int rv; 1824 1825 rv = rsc_cache_create_net(net); 1826 if (rv) 1827 return rv; 1828 rv = rsi_cache_create_net(net); 1829 if (rv) 1830 goto out1; 1831 rv = create_use_gss_proxy_proc_entry(net); 1832 if (rv) 1833 goto out2; 1834 return 0; 1835out2: 1836 destroy_use_gss_proxy_proc_entry(net); 1837out1: 1838 rsc_cache_destroy_net(net); 1839 return rv; 1840} 1841 1842void 1843gss_svc_shutdown_net(struct net *net) 1844{ 1845 destroy_use_gss_proxy_proc_entry(net); 1846 rsi_cache_destroy_net(net); 1847 rsc_cache_destroy_net(net); 1848} 1849 1850int 1851gss_svc_init(void) 1852{ 1853 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss); 1854} 1855 1856void 1857gss_svc_shutdown(void) 1858{ 1859 svc_auth_unregister(RPC_AUTH_GSS); 1860} 1861