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#if IS_ENABLED(CONFIG_SUNRPC_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 if (N < 0 || N > NGROUPS_MAX) 467 goto out; 468 status = -ENOMEM; 469 rsci.cred.cr_group_info = groups_alloc(N); 470 if (rsci.cred.cr_group_info == NULL) 471 goto out; 472 473 /* gid's */ 474 status = -EINVAL; 475 for (i=0; i<N; i++) { 476 kgid_t kgid; 477 if (get_int(&mesg, &id)) 478 goto out; 479 kgid = make_kgid(&init_user_ns, id); 480 if (!gid_valid(kgid)) 481 goto out; 482 GROUP_AT(rsci.cred.cr_group_info, i) = kgid; 483 } 484 485 /* mech name */ 486 len = qword_get(&mesg, buf, mlen); 487 if (len < 0) 488 goto out; 489 gm = rsci.cred.cr_gss_mech = gss_mech_get_by_name(buf); 490 status = -EOPNOTSUPP; 491 if (!gm) 492 goto out; 493 494 status = -EINVAL; 495 /* mech-specific data: */ 496 len = qword_get(&mesg, buf, mlen); 497 if (len < 0) 498 goto out; 499 status = gss_import_sec_context(buf, len, gm, &rsci.mechctx, 500 NULL, GFP_KERNEL); 501 if (status) 502 goto out; 503 504 /* get client name */ 505 len = qword_get(&mesg, buf, mlen); 506 if (len > 0) { 507 rsci.cred.cr_principal = kstrdup(buf, GFP_KERNEL); 508 if (!rsci.cred.cr_principal) { 509 status = -ENOMEM; 510 goto out; 511 } 512 } 513 514 } 515 rsci.h.expiry_time = expiry; 516 rscp = rsc_update(cd, &rsci, rscp); 517 status = 0; 518out: 519 rsc_free(&rsci); 520 if (rscp) 521 cache_put(&rscp->h, cd); 522 else 523 status = -ENOMEM; 524 return status; 525} 526 527static struct cache_detail rsc_cache_template = { 528 .owner = THIS_MODULE, 529 .hash_size = RSC_HASHMAX, 530 .name = "auth.rpcsec.context", 531 .cache_put = rsc_put, 532 .cache_parse = rsc_parse, 533 .match = rsc_match, 534 .init = rsc_init, 535 .update = update_rsc, 536 .alloc = rsc_alloc, 537}; 538 539static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item) 540{ 541 struct cache_head *ch; 542 int hash = rsc_hash(item); 543 544 ch = sunrpc_cache_lookup(cd, &item->h, hash); 545 if (ch) 546 return container_of(ch, struct rsc, h); 547 else 548 return NULL; 549} 550 551static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old) 552{ 553 struct cache_head *ch; 554 int hash = rsc_hash(new); 555 556 ch = sunrpc_cache_update(cd, &new->h, 557 &old->h, hash); 558 if (ch) 559 return container_of(ch, struct rsc, h); 560 else 561 return NULL; 562} 563 564 565static struct rsc * 566gss_svc_searchbyctx(struct cache_detail *cd, struct xdr_netobj *handle) 567{ 568 struct rsc rsci; 569 struct rsc *found; 570 571 memset(&rsci, 0, sizeof(rsci)); 572 if (dup_to_netobj(&rsci.handle, handle->data, handle->len)) 573 return NULL; 574 found = rsc_lookup(cd, &rsci); 575 rsc_free(&rsci); 576 if (!found) 577 return NULL; 578 if (cache_check(cd, &found->h, NULL)) 579 return NULL; 580 return found; 581} 582 583/* Implements sequence number algorithm as specified in RFC 2203. */ 584static int 585gss_check_seq_num(struct rsc *rsci, int seq_num) 586{ 587 struct gss_svc_seq_data *sd = &rsci->seqdata; 588 589 spin_lock(&sd->sd_lock); 590 if (seq_num > sd->sd_max) { 591 if (seq_num >= sd->sd_max + GSS_SEQ_WIN) { 592 memset(sd->sd_win,0,sizeof(sd->sd_win)); 593 sd->sd_max = seq_num; 594 } else while (sd->sd_max < seq_num) { 595 sd->sd_max++; 596 __clear_bit(sd->sd_max % GSS_SEQ_WIN, sd->sd_win); 597 } 598 __set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win); 599 goto ok; 600 } else if (seq_num <= sd->sd_max - GSS_SEQ_WIN) { 601 goto drop; 602 } 603 /* sd_max - GSS_SEQ_WIN < seq_num <= sd_max */ 604 if (__test_and_set_bit(seq_num % GSS_SEQ_WIN, sd->sd_win)) 605 goto drop; 606ok: 607 spin_unlock(&sd->sd_lock); 608 return 1; 609drop: 610 spin_unlock(&sd->sd_lock); 611 return 0; 612} 613 614static inline u32 round_up_to_quad(u32 i) 615{ 616 return (i + 3 ) & ~3; 617} 618 619static inline int 620svc_safe_getnetobj(struct kvec *argv, struct xdr_netobj *o) 621{ 622 int l; 623 624 if (argv->iov_len < 4) 625 return -1; 626 o->len = svc_getnl(argv); 627 l = round_up_to_quad(o->len); 628 if (argv->iov_len < l) 629 return -1; 630 o->data = argv->iov_base; 631 argv->iov_base += l; 632 argv->iov_len -= l; 633 return 0; 634} 635 636static inline int 637svc_safe_putnetobj(struct kvec *resv, struct xdr_netobj *o) 638{ 639 u8 *p; 640 641 if (resv->iov_len + 4 > PAGE_SIZE) 642 return -1; 643 svc_putnl(resv, o->len); 644 p = resv->iov_base + resv->iov_len; 645 resv->iov_len += round_up_to_quad(o->len); 646 if (resv->iov_len > PAGE_SIZE) 647 return -1; 648 memcpy(p, o->data, o->len); 649 memset(p + o->len, 0, round_up_to_quad(o->len) - o->len); 650 return 0; 651} 652 653/* 654 * Verify the checksum on the header and return SVC_OK on success. 655 * Otherwise, return SVC_DROP (in the case of a bad sequence number) 656 * or return SVC_DENIED and indicate error in authp. 657 */ 658static int 659gss_verify_header(struct svc_rqst *rqstp, struct rsc *rsci, 660 __be32 *rpcstart, struct rpc_gss_wire_cred *gc, __be32 *authp) 661{ 662 struct gss_ctx *ctx_id = rsci->mechctx; 663 struct xdr_buf rpchdr; 664 struct xdr_netobj checksum; 665 u32 flavor = 0; 666 struct kvec *argv = &rqstp->rq_arg.head[0]; 667 struct kvec iov; 668 669 /* data to compute the checksum over: */ 670 iov.iov_base = rpcstart; 671 iov.iov_len = (u8 *)argv->iov_base - (u8 *)rpcstart; 672 xdr_buf_from_iov(&iov, &rpchdr); 673 674 *authp = rpc_autherr_badverf; 675 if (argv->iov_len < 4) 676 return SVC_DENIED; 677 flavor = svc_getnl(argv); 678 if (flavor != RPC_AUTH_GSS) 679 return SVC_DENIED; 680 if (svc_safe_getnetobj(argv, &checksum)) 681 return SVC_DENIED; 682 683 if (rqstp->rq_deferred) /* skip verification of revisited request */ 684 return SVC_OK; 685 if (gss_verify_mic(ctx_id, &rpchdr, &checksum) != GSS_S_COMPLETE) { 686 *authp = rpcsec_gsserr_credproblem; 687 return SVC_DENIED; 688 } 689 690 if (gc->gc_seq > MAXSEQ) { 691 dprintk("RPC: svcauth_gss: discarding request with " 692 "large sequence number %d\n", gc->gc_seq); 693 *authp = rpcsec_gsserr_ctxproblem; 694 return SVC_DENIED; 695 } 696 if (!gss_check_seq_num(rsci, gc->gc_seq)) { 697 dprintk("RPC: svcauth_gss: discarding request with " 698 "old sequence number %d\n", gc->gc_seq); 699 return SVC_DROP; 700 } 701 return SVC_OK; 702} 703 704static int 705gss_write_null_verf(struct svc_rqst *rqstp) 706{ 707 __be32 *p; 708 709 svc_putnl(rqstp->rq_res.head, RPC_AUTH_NULL); 710 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len; 711 /* don't really need to check if head->iov_len > PAGE_SIZE ... */ 712 *p++ = 0; 713 if (!xdr_ressize_check(rqstp, p)) 714 return -1; 715 return 0; 716} 717 718static int 719gss_write_verf(struct svc_rqst *rqstp, struct gss_ctx *ctx_id, u32 seq) 720{ 721 __be32 xdr_seq; 722 u32 maj_stat; 723 struct xdr_buf verf_data; 724 struct xdr_netobj mic; 725 __be32 *p; 726 struct kvec iov; 727 728 svc_putnl(rqstp->rq_res.head, RPC_AUTH_GSS); 729 xdr_seq = htonl(seq); 730 731 iov.iov_base = &xdr_seq; 732 iov.iov_len = sizeof(xdr_seq); 733 xdr_buf_from_iov(&iov, &verf_data); 734 p = rqstp->rq_res.head->iov_base + rqstp->rq_res.head->iov_len; 735 mic.data = (u8 *)(p + 1); 736 maj_stat = gss_get_mic(ctx_id, &verf_data, &mic); 737 if (maj_stat != GSS_S_COMPLETE) 738 return -1; 739 *p++ = htonl(mic.len); 740 memset((u8 *)p + mic.len, 0, round_up_to_quad(mic.len) - mic.len); 741 p += XDR_QUADLEN(mic.len); 742 if (!xdr_ressize_check(rqstp, p)) 743 return -1; 744 return 0; 745} 746 747struct gss_domain { 748 struct auth_domain h; 749 u32 pseudoflavor; 750}; 751 752static struct auth_domain * 753find_gss_auth_domain(struct gss_ctx *ctx, u32 svc) 754{ 755 char *name; 756 757 name = gss_service_to_auth_domain_name(ctx->mech_type, svc); 758 if (!name) 759 return NULL; 760 return auth_domain_find(name); 761} 762 763static struct auth_ops svcauthops_gss; 764 765u32 svcauth_gss_flavor(struct auth_domain *dom) 766{ 767 struct gss_domain *gd = container_of(dom, struct gss_domain, h); 768 769 return gd->pseudoflavor; 770} 771 772EXPORT_SYMBOL_GPL(svcauth_gss_flavor); 773 774int 775svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name) 776{ 777 struct gss_domain *new; 778 struct auth_domain *test; 779 int stat = -ENOMEM; 780 781 new = kmalloc(sizeof(*new), GFP_KERNEL); 782 if (!new) 783 goto out; 784 kref_init(&new->h.ref); 785 new->h.name = kstrdup(name, GFP_KERNEL); 786 if (!new->h.name) 787 goto out_free_dom; 788 new->h.flavour = &svcauthops_gss; 789 new->pseudoflavor = pseudoflavor; 790 791 stat = 0; 792 test = auth_domain_lookup(name, &new->h); 793 if (test != &new->h) { /* Duplicate registration */ 794 auth_domain_put(test); 795 kfree(new->h.name); 796 goto out_free_dom; 797 } 798 return 0; 799 800out_free_dom: 801 kfree(new); 802out: 803 return stat; 804} 805 806EXPORT_SYMBOL_GPL(svcauth_gss_register_pseudoflavor); 807 808static inline int 809read_u32_from_xdr_buf(struct xdr_buf *buf, int base, u32 *obj) 810{ 811 __be32 raw; 812 int status; 813 814 status = read_bytes_from_xdr_buf(buf, base, &raw, sizeof(*obj)); 815 if (status) 816 return status; 817 *obj = ntohl(raw); 818 return 0; 819} 820 821/* It would be nice if this bit of code could be shared with the client. 822 * Obstacles: 823 * The client shouldn't malloc(), would have to pass in own memory. 824 * The server uses base of head iovec as read pointer, while the 825 * client uses separate pointer. */ 826static int 827unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx) 828{ 829 int stat = -EINVAL; 830 u32 integ_len, maj_stat; 831 struct xdr_netobj mic; 832 struct xdr_buf integ_buf; 833 834 /* Did we already verify the signature on the original pass through? */ 835 if (rqstp->rq_deferred) 836 return 0; 837 838 integ_len = svc_getnl(&buf->head[0]); 839 if (integ_len & 3) 840 return stat; 841 if (integ_len > buf->len) 842 return stat; 843 if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) 844 BUG(); 845 /* copy out mic... */ 846 if (read_u32_from_xdr_buf(buf, integ_len, &mic.len)) 847 BUG(); 848 if (mic.len > RPC_MAX_AUTH_SIZE) 849 return stat; 850 mic.data = kmalloc(mic.len, GFP_KERNEL); 851 if (!mic.data) 852 return stat; 853 if (read_bytes_from_xdr_buf(buf, integ_len + 4, mic.data, mic.len)) 854 goto out; 855 maj_stat = gss_verify_mic(ctx, &integ_buf, &mic); 856 if (maj_stat != GSS_S_COMPLETE) 857 goto out; 858 if (svc_getnl(&buf->head[0]) != seq) 859 goto out; 860 /* trim off the mic and padding at the end before returning */ 861 xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4); 862 stat = 0; 863out: 864 kfree(mic.data); 865 return stat; 866} 867 868static inline int 869total_buf_len(struct xdr_buf *buf) 870{ 871 return buf->head[0].iov_len + buf->page_len + buf->tail[0].iov_len; 872} 873 874static void 875fix_priv_head(struct xdr_buf *buf, int pad) 876{ 877 if (buf->page_len == 0) { 878 /* We need to adjust head and buf->len in tandem in this 879 * case to make svc_defer() work--it finds the original 880 * buffer start using buf->len - buf->head[0].iov_len. */ 881 buf->head[0].iov_len -= pad; 882 } 883} 884 885static int 886unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx) 887{ 888 u32 priv_len, maj_stat; 889 int pad, saved_len, remaining_len, offset; 890 891 clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags); 892 893 priv_len = svc_getnl(&buf->head[0]); 894 if (rqstp->rq_deferred) { 895 /* Already decrypted last time through! The sequence number 896 * check at out_seq is unnecessary but harmless: */ 897 goto out_seq; 898 } 899 /* buf->len is the number of bytes from the original start of the 900 * request to the end, where head[0].iov_len is just the bytes 901 * not yet read from the head, so these two values are different: */ 902 remaining_len = total_buf_len(buf); 903 if (priv_len > remaining_len) 904 return -EINVAL; 905 pad = remaining_len - priv_len; 906 buf->len -= pad; 907 fix_priv_head(buf, pad); 908 909 /* Maybe it would be better to give gss_unwrap a length parameter: */ 910 saved_len = buf->len; 911 buf->len = priv_len; 912 maj_stat = gss_unwrap(ctx, 0, buf); 913 pad = priv_len - buf->len; 914 buf->len = saved_len; 915 buf->len -= pad; 916 /* The upper layers assume the buffer is aligned on 4-byte boundaries. 917 * In the krb5p case, at least, the data ends up offset, so we need to 918 * move it around. */ 919 /* XXX: This is very inefficient. It would be better to either do 920 * this while we encrypt, or maybe in the receive code, if we can peak 921 * ahead and work out the service and mechanism there. */ 922 offset = buf->head[0].iov_len % 4; 923 if (offset) { 924 buf->buflen = RPCSVC_MAXPAYLOAD; 925 xdr_shift_buf(buf, offset); 926 fix_priv_head(buf, pad); 927 } 928 if (maj_stat != GSS_S_COMPLETE) 929 return -EINVAL; 930out_seq: 931 if (svc_getnl(&buf->head[0]) != seq) 932 return -EINVAL; 933 return 0; 934} 935 936struct gss_svc_data { 937 /* decoded gss client cred: */ 938 struct rpc_gss_wire_cred clcred; 939 /* save a pointer to the beginning of the encoded verifier, 940 * for use in encryption/checksumming in svcauth_gss_release: */ 941 __be32 *verf_start; 942 struct rsc *rsci; 943}; 944 945static int 946svcauth_gss_set_client(struct svc_rqst *rqstp) 947{ 948 struct gss_svc_data *svcdata = rqstp->rq_auth_data; 949 struct rsc *rsci = svcdata->rsci; 950 struct rpc_gss_wire_cred *gc = &svcdata->clcred; 951 int stat; 952 953 /* 954 * A gss export can be specified either by: 955 * export *(sec=krb5,rw) 956 * or by 957 * export gss/krb5(rw) 958 * The latter is deprecated; but for backwards compatibility reasons 959 * the nfsd code will still fall back on trying it if the former 960 * doesn't work; so we try to make both available to nfsd, below. 961 */ 962 rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc); 963 if (rqstp->rq_gssclient == NULL) 964 return SVC_DENIED; 965 stat = svcauth_unix_set_client(rqstp); 966 if (stat == SVC_DROP || stat == SVC_CLOSE) 967 return stat; 968 return SVC_OK; 969} 970 971static inline int 972gss_write_init_verf(struct cache_detail *cd, struct svc_rqst *rqstp, 973 struct xdr_netobj *out_handle, int *major_status) 974{ 975 struct rsc *rsci; 976 int rc; 977 978 if (*major_status != GSS_S_COMPLETE) 979 return gss_write_null_verf(rqstp); 980 rsci = gss_svc_searchbyctx(cd, out_handle); 981 if (rsci == NULL) { 982 *major_status = GSS_S_NO_CONTEXT; 983 return gss_write_null_verf(rqstp); 984 } 985 rc = gss_write_verf(rqstp, rsci->mechctx, GSS_SEQ_WIN); 986 cache_put(&rsci->h, cd); 987 return rc; 988} 989 990static inline int 991gss_read_common_verf(struct rpc_gss_wire_cred *gc, 992 struct kvec *argv, __be32 *authp, 993 struct xdr_netobj *in_handle) 994{ 995 /* Read the verifier; should be NULL: */ 996 *authp = rpc_autherr_badverf; 997 if (argv->iov_len < 2 * 4) 998 return SVC_DENIED; 999 if (svc_getnl(argv) != RPC_AUTH_NULL) 1000 return SVC_DENIED; 1001 if (svc_getnl(argv) != 0) 1002 return SVC_DENIED; 1003 /* Martial context handle and token for upcall: */ 1004 *authp = rpc_autherr_badcred; 1005 if (gc->gc_proc == RPC_GSS_PROC_INIT && gc->gc_ctx.len != 0) 1006 return SVC_DENIED; 1007 if (dup_netobj(in_handle, &gc->gc_ctx)) 1008 return SVC_CLOSE; 1009 *authp = rpc_autherr_badverf; 1010 1011 return 0; 1012} 1013 1014static inline int 1015gss_read_verf(struct rpc_gss_wire_cred *gc, 1016 struct kvec *argv, __be32 *authp, 1017 struct xdr_netobj *in_handle, 1018 struct xdr_netobj *in_token) 1019{ 1020 struct xdr_netobj tmpobj; 1021 int res; 1022 1023 res = gss_read_common_verf(gc, argv, authp, in_handle); 1024 if (res) 1025 return res; 1026 1027 if (svc_safe_getnetobj(argv, &tmpobj)) { 1028 kfree(in_handle->data); 1029 return SVC_DENIED; 1030 } 1031 if (dup_netobj(in_token, &tmpobj)) { 1032 kfree(in_handle->data); 1033 return SVC_CLOSE; 1034 } 1035 1036 return 0; 1037} 1038 1039/* Ok this is really heavily depending on a set of semantics in 1040 * how rqstp is set up by svc_recv and pages laid down by the 1041 * server when reading a request. We are basically guaranteed that 1042 * the token lays all down linearly across a set of pages, starting 1043 * at iov_base in rq_arg.head[0] which happens to be the first of a 1044 * set of pages stored in rq_pages[]. 1045 * rq_arg.head[0].iov_base will provide us the page_base to pass 1046 * to the upcall. 1047 */ 1048static inline int 1049gss_read_proxy_verf(struct svc_rqst *rqstp, 1050 struct rpc_gss_wire_cred *gc, __be32 *authp, 1051 struct xdr_netobj *in_handle, 1052 struct gssp_in_token *in_token) 1053{ 1054 struct kvec *argv = &rqstp->rq_arg.head[0]; 1055 u32 inlen; 1056 int res; 1057 1058 res = gss_read_common_verf(gc, argv, authp, in_handle); 1059 if (res) 1060 return res; 1061 1062 inlen = svc_getnl(argv); 1063 if (inlen > (argv->iov_len + rqstp->rq_arg.page_len)) 1064 return SVC_DENIED; 1065 1066 in_token->pages = rqstp->rq_pages; 1067 in_token->page_base = (ulong)argv->iov_base & ~PAGE_MASK; 1068 in_token->page_len = inlen; 1069 1070 return 0; 1071} 1072 1073static inline int 1074gss_write_resv(struct kvec *resv, size_t size_limit, 1075 struct xdr_netobj *out_handle, struct xdr_netobj *out_token, 1076 int major_status, int minor_status) 1077{ 1078 if (resv->iov_len + 4 > size_limit) 1079 return -1; 1080 svc_putnl(resv, RPC_SUCCESS); 1081 if (svc_safe_putnetobj(resv, out_handle)) 1082 return -1; 1083 if (resv->iov_len + 3 * 4 > size_limit) 1084 return -1; 1085 svc_putnl(resv, major_status); 1086 svc_putnl(resv, minor_status); 1087 svc_putnl(resv, GSS_SEQ_WIN); 1088 if (svc_safe_putnetobj(resv, out_token)) 1089 return -1; 1090 return 0; 1091} 1092 1093/* 1094 * Having read the cred already and found we're in the context 1095 * initiation case, read the verifier and initiate (or check the results 1096 * of) upcalls to userspace for help with context initiation. If 1097 * the upcall results are available, write the verifier and result. 1098 * Otherwise, drop the request pending an answer to the upcall. 1099 */ 1100static int svcauth_gss_legacy_init(struct svc_rqst *rqstp, 1101 struct rpc_gss_wire_cred *gc, __be32 *authp) 1102{ 1103 struct kvec *argv = &rqstp->rq_arg.head[0]; 1104 struct kvec *resv = &rqstp->rq_res.head[0]; 1105 struct rsi *rsip, rsikey; 1106 int ret; 1107 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1108 1109 memset(&rsikey, 0, sizeof(rsikey)); 1110 ret = gss_read_verf(gc, argv, authp, 1111 &rsikey.in_handle, &rsikey.in_token); 1112 if (ret) 1113 return ret; 1114 1115 /* Perform upcall, or find upcall result: */ 1116 rsip = rsi_lookup(sn->rsi_cache, &rsikey); 1117 rsi_free(&rsikey); 1118 if (!rsip) 1119 return SVC_CLOSE; 1120 if (cache_check(sn->rsi_cache, &rsip->h, &rqstp->rq_chandle) < 0) 1121 /* No upcall result: */ 1122 return SVC_CLOSE; 1123 1124 ret = SVC_CLOSE; 1125 /* Got an answer to the upcall; use it: */ 1126 if (gss_write_init_verf(sn->rsc_cache, rqstp, 1127 &rsip->out_handle, &rsip->major_status)) 1128 goto out; 1129 if (gss_write_resv(resv, PAGE_SIZE, 1130 &rsip->out_handle, &rsip->out_token, 1131 rsip->major_status, rsip->minor_status)) 1132 goto out; 1133 1134 ret = SVC_COMPLETE; 1135out: 1136 cache_put(&rsip->h, sn->rsi_cache); 1137 return ret; 1138} 1139 1140static int gss_proxy_save_rsc(struct cache_detail *cd, 1141 struct gssp_upcall_data *ud, 1142 uint64_t *handle) 1143{ 1144 struct rsc rsci, *rscp = NULL; 1145 static atomic64_t ctxhctr; 1146 long long ctxh; 1147 struct gss_api_mech *gm = NULL; 1148 time_t expiry; 1149 int status = -EINVAL; 1150 1151 memset(&rsci, 0, sizeof(rsci)); 1152 /* context handle */ 1153 status = -ENOMEM; 1154 /* the handle needs to be just a unique id, 1155 * use a static counter */ 1156 ctxh = atomic64_inc_return(&ctxhctr); 1157 1158 /* make a copy for the caller */ 1159 *handle = ctxh; 1160 1161 /* make a copy for the rsc cache */ 1162 if (dup_to_netobj(&rsci.handle, (char *)handle, sizeof(uint64_t))) 1163 goto out; 1164 rscp = rsc_lookup(cd, &rsci); 1165 if (!rscp) 1166 goto out; 1167 1168 /* creds */ 1169 if (!ud->found_creds) { 1170 /* userspace seem buggy, we should always get at least a 1171 * mapping to nobody */ 1172 dprintk("RPC: No creds found!\n"); 1173 goto out; 1174 } else { 1175 1176 /* steal creds */ 1177 rsci.cred = ud->creds; 1178 memset(&ud->creds, 0, sizeof(struct svc_cred)); 1179 1180 status = -EOPNOTSUPP; 1181 /* get mech handle from OID */ 1182 gm = gss_mech_get_by_OID(&ud->mech_oid); 1183 if (!gm) 1184 goto out; 1185 rsci.cred.cr_gss_mech = gm; 1186 1187 status = -EINVAL; 1188 /* mech-specific data: */ 1189 status = gss_import_sec_context(ud->out_handle.data, 1190 ud->out_handle.len, 1191 gm, &rsci.mechctx, 1192 &expiry, GFP_KERNEL); 1193 if (status) 1194 goto out; 1195 } 1196 1197 rsci.h.expiry_time = expiry; 1198 rscp = rsc_update(cd, &rsci, rscp); 1199 status = 0; 1200out: 1201 rsc_free(&rsci); 1202 if (rscp) 1203 cache_put(&rscp->h, cd); 1204 else 1205 status = -ENOMEM; 1206 return status; 1207} 1208 1209static int svcauth_gss_proxy_init(struct svc_rqst *rqstp, 1210 struct rpc_gss_wire_cred *gc, __be32 *authp) 1211{ 1212 struct kvec *resv = &rqstp->rq_res.head[0]; 1213 struct xdr_netobj cli_handle; 1214 struct gssp_upcall_data ud; 1215 uint64_t handle; 1216 int status; 1217 int ret; 1218 struct net *net = rqstp->rq_xprt->xpt_net; 1219 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1220 1221 memset(&ud, 0, sizeof(ud)); 1222 ret = gss_read_proxy_verf(rqstp, gc, authp, 1223 &ud.in_handle, &ud.in_token); 1224 if (ret) 1225 return ret; 1226 1227 ret = SVC_CLOSE; 1228 1229 /* Perform synchronous upcall to gss-proxy */ 1230 status = gssp_accept_sec_context_upcall(net, &ud); 1231 if (status) 1232 goto out; 1233 1234 dprintk("RPC: svcauth_gss: gss major status = %d\n", 1235 ud.major_status); 1236 1237 switch (ud.major_status) { 1238 case GSS_S_CONTINUE_NEEDED: 1239 cli_handle = ud.out_handle; 1240 break; 1241 case GSS_S_COMPLETE: 1242 status = gss_proxy_save_rsc(sn->rsc_cache, &ud, &handle); 1243 if (status) 1244 goto out; 1245 cli_handle.data = (u8 *)&handle; 1246 cli_handle.len = sizeof(handle); 1247 break; 1248 default: 1249 ret = SVC_CLOSE; 1250 goto out; 1251 } 1252 1253 /* Got an answer to the upcall; use it: */ 1254 if (gss_write_init_verf(sn->rsc_cache, rqstp, 1255 &cli_handle, &ud.major_status)) 1256 goto out; 1257 if (gss_write_resv(resv, PAGE_SIZE, 1258 &cli_handle, &ud.out_token, 1259 ud.major_status, ud.minor_status)) 1260 goto out; 1261 1262 ret = SVC_COMPLETE; 1263out: 1264 gssp_free_upcall_data(&ud); 1265 return ret; 1266} 1267 1268/* 1269 * Try to set the sn->use_gss_proxy variable to a new value. We only allow 1270 * it to be changed if it's currently undefined (-1). If it's any other value 1271 * then return -EBUSY unless the type wouldn't have changed anyway. 1272 */ 1273static int set_gss_proxy(struct net *net, int type) 1274{ 1275 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1276 int ret; 1277 1278 WARN_ON_ONCE(type != 0 && type != 1); 1279 ret = cmpxchg(&sn->use_gss_proxy, -1, type); 1280 if (ret != -1 && ret != type) 1281 return -EBUSY; 1282 return 0; 1283} 1284 1285static bool use_gss_proxy(struct net *net) 1286{ 1287 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1288 1289 /* If use_gss_proxy is still undefined, then try to disable it */ 1290 if (sn->use_gss_proxy == -1) 1291 set_gss_proxy(net, 0); 1292 return sn->use_gss_proxy; 1293} 1294 1295#ifdef CONFIG_PROC_FS 1296 1297static ssize_t write_gssp(struct file *file, const char __user *buf, 1298 size_t count, loff_t *ppos) 1299{ 1300 struct net *net = PDE_DATA(file_inode(file)); 1301 char tbuf[20]; 1302 unsigned long i; 1303 int res; 1304 1305 if (*ppos || count > sizeof(tbuf)-1) 1306 return -EINVAL; 1307 if (copy_from_user(tbuf, buf, count)) 1308 return -EFAULT; 1309 1310 tbuf[count] = 0; 1311 res = kstrtoul(tbuf, 0, &i); 1312 if (res) 1313 return res; 1314 if (i != 1) 1315 return -EINVAL; 1316 res = set_gssp_clnt(net); 1317 if (res) 1318 return res; 1319 res = set_gss_proxy(net, 1); 1320 if (res) 1321 return res; 1322 return count; 1323} 1324 1325static ssize_t read_gssp(struct file *file, char __user *buf, 1326 size_t count, loff_t *ppos) 1327{ 1328 struct net *net = PDE_DATA(file_inode(file)); 1329 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1330 unsigned long p = *ppos; 1331 char tbuf[10]; 1332 size_t len; 1333 1334 snprintf(tbuf, sizeof(tbuf), "%d\n", sn->use_gss_proxy); 1335 len = strlen(tbuf); 1336 if (p >= len) 1337 return 0; 1338 len -= p; 1339 if (len > count) 1340 len = count; 1341 if (copy_to_user(buf, (void *)(tbuf+p), len)) 1342 return -EFAULT; 1343 *ppos += len; 1344 return len; 1345} 1346 1347static const struct file_operations use_gss_proxy_ops = { 1348 .open = nonseekable_open, 1349 .write = write_gssp, 1350 .read = read_gssp, 1351}; 1352 1353static int create_use_gss_proxy_proc_entry(struct net *net) 1354{ 1355 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1356 struct proc_dir_entry **p = &sn->use_gssp_proc; 1357 1358 sn->use_gss_proxy = -1; 1359 *p = proc_create_data("use-gss-proxy", S_IFREG|S_IRUSR|S_IWUSR, 1360 sn->proc_net_rpc, 1361 &use_gss_proxy_ops, net); 1362 if (!*p) 1363 return -ENOMEM; 1364 init_gssp_clnt(sn); 1365 return 0; 1366} 1367 1368static void destroy_use_gss_proxy_proc_entry(struct net *net) 1369{ 1370 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1371 1372 if (sn->use_gssp_proc) { 1373 remove_proc_entry("use-gss-proxy", sn->proc_net_rpc); 1374 clear_gssp_clnt(sn); 1375 } 1376} 1377#else /* CONFIG_PROC_FS */ 1378 1379static int create_use_gss_proxy_proc_entry(struct net *net) 1380{ 1381 return 0; 1382} 1383 1384static void destroy_use_gss_proxy_proc_entry(struct net *net) {} 1385 1386#endif /* CONFIG_PROC_FS */ 1387 1388/* 1389 * Accept an rpcsec packet. 1390 * If context establishment, punt to user space 1391 * If data exchange, verify/decrypt 1392 * If context destruction, handle here 1393 * In the context establishment and destruction case we encode 1394 * response here and return SVC_COMPLETE. 1395 */ 1396static int 1397svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp) 1398{ 1399 struct kvec *argv = &rqstp->rq_arg.head[0]; 1400 struct kvec *resv = &rqstp->rq_res.head[0]; 1401 u32 crlen; 1402 struct gss_svc_data *svcdata = rqstp->rq_auth_data; 1403 struct rpc_gss_wire_cred *gc; 1404 struct rsc *rsci = NULL; 1405 __be32 *rpcstart; 1406 __be32 *reject_stat = resv->iov_base + resv->iov_len; 1407 int ret; 1408 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1409 1410 dprintk("RPC: svcauth_gss: argv->iov_len = %zd\n", 1411 argv->iov_len); 1412 1413 *authp = rpc_autherr_badcred; 1414 if (!svcdata) 1415 svcdata = kmalloc(sizeof(*svcdata), GFP_KERNEL); 1416 if (!svcdata) 1417 goto auth_err; 1418 rqstp->rq_auth_data = svcdata; 1419 svcdata->verf_start = NULL; 1420 svcdata->rsci = NULL; 1421 gc = &svcdata->clcred; 1422 1423 /* start of rpc packet is 7 u32's back from here: 1424 * xid direction rpcversion prog vers proc flavour 1425 */ 1426 rpcstart = argv->iov_base; 1427 rpcstart -= 7; 1428 1429 /* credential is: 1430 * version(==1), proc(0,1,2,3), seq, service (1,2,3), handle 1431 * at least 5 u32s, and is preceded by length, so that makes 6. 1432 */ 1433 1434 if (argv->iov_len < 5 * 4) 1435 goto auth_err; 1436 crlen = svc_getnl(argv); 1437 if (svc_getnl(argv) != RPC_GSS_VERSION) 1438 goto auth_err; 1439 gc->gc_proc = svc_getnl(argv); 1440 gc->gc_seq = svc_getnl(argv); 1441 gc->gc_svc = svc_getnl(argv); 1442 if (svc_safe_getnetobj(argv, &gc->gc_ctx)) 1443 goto auth_err; 1444 if (crlen != round_up_to_quad(gc->gc_ctx.len) + 5 * 4) 1445 goto auth_err; 1446 1447 if ((gc->gc_proc != RPC_GSS_PROC_DATA) && (rqstp->rq_proc != 0)) 1448 goto auth_err; 1449 1450 *authp = rpc_autherr_badverf; 1451 switch (gc->gc_proc) { 1452 case RPC_GSS_PROC_INIT: 1453 case RPC_GSS_PROC_CONTINUE_INIT: 1454 if (use_gss_proxy(SVC_NET(rqstp))) 1455 return svcauth_gss_proxy_init(rqstp, gc, authp); 1456 else 1457 return svcauth_gss_legacy_init(rqstp, gc, authp); 1458 case RPC_GSS_PROC_DATA: 1459 case RPC_GSS_PROC_DESTROY: 1460 /* Look up the context, and check the verifier: */ 1461 *authp = rpcsec_gsserr_credproblem; 1462 rsci = gss_svc_searchbyctx(sn->rsc_cache, &gc->gc_ctx); 1463 if (!rsci) 1464 goto auth_err; 1465 switch (gss_verify_header(rqstp, rsci, rpcstart, gc, authp)) { 1466 case SVC_OK: 1467 break; 1468 case SVC_DENIED: 1469 goto auth_err; 1470 case SVC_DROP: 1471 goto drop; 1472 } 1473 break; 1474 default: 1475 *authp = rpc_autherr_rejectedcred; 1476 goto auth_err; 1477 } 1478 1479 /* now act upon the command: */ 1480 switch (gc->gc_proc) { 1481 case RPC_GSS_PROC_DESTROY: 1482 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq)) 1483 goto auth_err; 1484 rsci->h.expiry_time = get_seconds(); 1485 set_bit(CACHE_NEGATIVE, &rsci->h.flags); 1486 if (resv->iov_len + 4 > PAGE_SIZE) 1487 goto drop; 1488 svc_putnl(resv, RPC_SUCCESS); 1489 goto complete; 1490 case RPC_GSS_PROC_DATA: 1491 *authp = rpcsec_gsserr_ctxproblem; 1492 svcdata->verf_start = resv->iov_base + resv->iov_len; 1493 if (gss_write_verf(rqstp, rsci->mechctx, gc->gc_seq)) 1494 goto auth_err; 1495 rqstp->rq_cred = rsci->cred; 1496 get_group_info(rsci->cred.cr_group_info); 1497 *authp = rpc_autherr_badcred; 1498 switch (gc->gc_svc) { 1499 case RPC_GSS_SVC_NONE: 1500 break; 1501 case RPC_GSS_SVC_INTEGRITY: 1502 /* placeholders for length and seq. number: */ 1503 svc_putnl(resv, 0); 1504 svc_putnl(resv, 0); 1505 if (unwrap_integ_data(rqstp, &rqstp->rq_arg, 1506 gc->gc_seq, rsci->mechctx)) 1507 goto garbage_args; 1508 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE; 1509 break; 1510 case RPC_GSS_SVC_PRIVACY: 1511 /* placeholders for length and seq. number: */ 1512 svc_putnl(resv, 0); 1513 svc_putnl(resv, 0); 1514 if (unwrap_priv_data(rqstp, &rqstp->rq_arg, 1515 gc->gc_seq, rsci->mechctx)) 1516 goto garbage_args; 1517 rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2; 1518 break; 1519 default: 1520 goto auth_err; 1521 } 1522 svcdata->rsci = rsci; 1523 cache_get(&rsci->h); 1524 rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor( 1525 rsci->mechctx->mech_type, 1526 GSS_C_QOP_DEFAULT, 1527 gc->gc_svc); 1528 ret = SVC_OK; 1529 goto out; 1530 } 1531garbage_args: 1532 ret = SVC_GARBAGE; 1533 goto out; 1534auth_err: 1535 /* Restore write pointer to its original value: */ 1536 xdr_ressize_check(rqstp, reject_stat); 1537 ret = SVC_DENIED; 1538 goto out; 1539complete: 1540 ret = SVC_COMPLETE; 1541 goto out; 1542drop: 1543 ret = SVC_DROP; 1544out: 1545 if (rsci) 1546 cache_put(&rsci->h, sn->rsc_cache); 1547 return ret; 1548} 1549 1550static __be32 * 1551svcauth_gss_prepare_to_wrap(struct xdr_buf *resbuf, struct gss_svc_data *gsd) 1552{ 1553 __be32 *p; 1554 u32 verf_len; 1555 1556 p = gsd->verf_start; 1557 gsd->verf_start = NULL; 1558 1559 /* If the reply stat is nonzero, don't wrap: */ 1560 if (*(p-1) != rpc_success) 1561 return NULL; 1562 /* Skip the verifier: */ 1563 p += 1; 1564 verf_len = ntohl(*p++); 1565 p += XDR_QUADLEN(verf_len); 1566 /* move accept_stat to right place: */ 1567 memcpy(p, p + 2, 4); 1568 /* Also don't wrap if the accept stat is nonzero: */ 1569 if (*p != rpc_success) { 1570 resbuf->head[0].iov_len -= 2 * 4; 1571 return NULL; 1572 } 1573 p++; 1574 return p; 1575} 1576 1577static inline int 1578svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp) 1579{ 1580 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1581 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1582 struct xdr_buf *resbuf = &rqstp->rq_res; 1583 struct xdr_buf integ_buf; 1584 struct xdr_netobj mic; 1585 struct kvec *resv; 1586 __be32 *p; 1587 int integ_offset, integ_len; 1588 int stat = -EINVAL; 1589 1590 p = svcauth_gss_prepare_to_wrap(resbuf, gsd); 1591 if (p == NULL) 1592 goto out; 1593 integ_offset = (u8 *)(p + 1) - (u8 *)resbuf->head[0].iov_base; 1594 integ_len = resbuf->len - integ_offset; 1595 BUG_ON(integ_len % 4); 1596 *p++ = htonl(integ_len); 1597 *p++ = htonl(gc->gc_seq); 1598 if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) 1599 BUG(); 1600 if (resbuf->tail[0].iov_base == NULL) { 1601 if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1602 goto out_err; 1603 resbuf->tail[0].iov_base = resbuf->head[0].iov_base 1604 + resbuf->head[0].iov_len; 1605 resbuf->tail[0].iov_len = 0; 1606 } 1607 resv = &resbuf->tail[0]; 1608 mic.data = (u8 *)resv->iov_base + resv->iov_len + 4; 1609 if (gss_get_mic(gsd->rsci->mechctx, &integ_buf, &mic)) 1610 goto out_err; 1611 svc_putnl(resv, mic.len); 1612 memset(mic.data + mic.len, 0, 1613 round_up_to_quad(mic.len) - mic.len); 1614 resv->iov_len += XDR_QUADLEN(mic.len) << 2; 1615 /* not strictly required: */ 1616 resbuf->len += XDR_QUADLEN(mic.len) << 2; 1617 BUG_ON(resv->iov_len > PAGE_SIZE); 1618out: 1619 stat = 0; 1620out_err: 1621 return stat; 1622} 1623 1624static inline int 1625svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp) 1626{ 1627 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1628 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1629 struct xdr_buf *resbuf = &rqstp->rq_res; 1630 struct page **inpages = NULL; 1631 __be32 *p, *len; 1632 int offset; 1633 int pad; 1634 1635 p = svcauth_gss_prepare_to_wrap(resbuf, gsd); 1636 if (p == NULL) 1637 return 0; 1638 len = p++; 1639 offset = (u8 *)p - (u8 *)resbuf->head[0].iov_base; 1640 *p++ = htonl(gc->gc_seq); 1641 inpages = resbuf->pages; 1642 /* XXX: Would be better to write some xdr helper functions for 1643 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */ 1644 1645 /* 1646 * If there is currently tail data, make sure there is 1647 * room for the head, tail, and 2 * RPC_MAX_AUTH_SIZE in 1648 * the page, and move the current tail data such that 1649 * there is RPC_MAX_AUTH_SIZE slack space available in 1650 * both the head and tail. 1651 */ 1652 if (resbuf->tail[0].iov_base) { 1653 BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base 1654 + PAGE_SIZE); 1655 BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base); 1656 if (resbuf->tail[0].iov_len + resbuf->head[0].iov_len 1657 + 2 * RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1658 return -ENOMEM; 1659 memmove(resbuf->tail[0].iov_base + RPC_MAX_AUTH_SIZE, 1660 resbuf->tail[0].iov_base, 1661 resbuf->tail[0].iov_len); 1662 resbuf->tail[0].iov_base += RPC_MAX_AUTH_SIZE; 1663 } 1664 /* 1665 * If there is no current tail data, make sure there is 1666 * room for the head data, and 2 * RPC_MAX_AUTH_SIZE in the 1667 * allotted page, and set up tail information such that there 1668 * is RPC_MAX_AUTH_SIZE slack space available in both the 1669 * head and tail. 1670 */ 1671 if (resbuf->tail[0].iov_base == NULL) { 1672 if (resbuf->head[0].iov_len + 2*RPC_MAX_AUTH_SIZE > PAGE_SIZE) 1673 return -ENOMEM; 1674 resbuf->tail[0].iov_base = resbuf->head[0].iov_base 1675 + resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE; 1676 resbuf->tail[0].iov_len = 0; 1677 } 1678 if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages)) 1679 return -ENOMEM; 1680 *len = htonl(resbuf->len - offset); 1681 pad = 3 - ((resbuf->len - offset - 1)&3); 1682 p = (__be32 *)(resbuf->tail[0].iov_base + resbuf->tail[0].iov_len); 1683 memset(p, 0, pad); 1684 resbuf->tail[0].iov_len += pad; 1685 resbuf->len += pad; 1686 return 0; 1687} 1688 1689static int 1690svcauth_gss_release(struct svc_rqst *rqstp) 1691{ 1692 struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; 1693 struct rpc_gss_wire_cred *gc = &gsd->clcred; 1694 struct xdr_buf *resbuf = &rqstp->rq_res; 1695 int stat = -EINVAL; 1696 struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net, sunrpc_net_id); 1697 1698 if (gc->gc_proc != RPC_GSS_PROC_DATA) 1699 goto out; 1700 /* Release can be called twice, but we only wrap once. */ 1701 if (gsd->verf_start == NULL) 1702 goto out; 1703 /* normally not set till svc_send, but we need it here: */ 1704 /* XXX: what for? Do we mess it up the moment we call svc_putu32 1705 * or whatever? */ 1706 resbuf->len = total_buf_len(resbuf); 1707 switch (gc->gc_svc) { 1708 case RPC_GSS_SVC_NONE: 1709 break; 1710 case RPC_GSS_SVC_INTEGRITY: 1711 stat = svcauth_gss_wrap_resp_integ(rqstp); 1712 if (stat) 1713 goto out_err; 1714 break; 1715 case RPC_GSS_SVC_PRIVACY: 1716 stat = svcauth_gss_wrap_resp_priv(rqstp); 1717 if (stat) 1718 goto out_err; 1719 break; 1720 /* 1721 * For any other gc_svc value, svcauth_gss_accept() already set 1722 * the auth_error appropriately; just fall through: 1723 */ 1724 } 1725 1726out: 1727 stat = 0; 1728out_err: 1729 if (rqstp->rq_client) 1730 auth_domain_put(rqstp->rq_client); 1731 rqstp->rq_client = NULL; 1732 if (rqstp->rq_gssclient) 1733 auth_domain_put(rqstp->rq_gssclient); 1734 rqstp->rq_gssclient = NULL; 1735 if (rqstp->rq_cred.cr_group_info) 1736 put_group_info(rqstp->rq_cred.cr_group_info); 1737 rqstp->rq_cred.cr_group_info = NULL; 1738 if (gsd->rsci) 1739 cache_put(&gsd->rsci->h, sn->rsc_cache); 1740 gsd->rsci = NULL; 1741 1742 return stat; 1743} 1744 1745static void 1746svcauth_gss_domain_release(struct auth_domain *dom) 1747{ 1748 struct gss_domain *gd = container_of(dom, struct gss_domain, h); 1749 1750 kfree(dom->name); 1751 kfree(gd); 1752} 1753 1754static struct auth_ops svcauthops_gss = { 1755 .name = "rpcsec_gss", 1756 .owner = THIS_MODULE, 1757 .flavour = RPC_AUTH_GSS, 1758 .accept = svcauth_gss_accept, 1759 .release = svcauth_gss_release, 1760 .domain_release = svcauth_gss_domain_release, 1761 .set_client = svcauth_gss_set_client, 1762}; 1763 1764static int rsi_cache_create_net(struct net *net) 1765{ 1766 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1767 struct cache_detail *cd; 1768 int err; 1769 1770 cd = cache_create_net(&rsi_cache_template, net); 1771 if (IS_ERR(cd)) 1772 return PTR_ERR(cd); 1773 err = cache_register_net(cd, net); 1774 if (err) { 1775 cache_destroy_net(cd, net); 1776 return err; 1777 } 1778 sn->rsi_cache = cd; 1779 return 0; 1780} 1781 1782static void rsi_cache_destroy_net(struct net *net) 1783{ 1784 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1785 struct cache_detail *cd = sn->rsi_cache; 1786 1787 sn->rsi_cache = NULL; 1788 cache_purge(cd); 1789 cache_unregister_net(cd, net); 1790 cache_destroy_net(cd, net); 1791} 1792 1793static int rsc_cache_create_net(struct net *net) 1794{ 1795 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1796 struct cache_detail *cd; 1797 int err; 1798 1799 cd = cache_create_net(&rsc_cache_template, net); 1800 if (IS_ERR(cd)) 1801 return PTR_ERR(cd); 1802 err = cache_register_net(cd, net); 1803 if (err) { 1804 cache_destroy_net(cd, net); 1805 return err; 1806 } 1807 sn->rsc_cache = cd; 1808 return 0; 1809} 1810 1811static void rsc_cache_destroy_net(struct net *net) 1812{ 1813 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1814 struct cache_detail *cd = sn->rsc_cache; 1815 1816 sn->rsc_cache = NULL; 1817 cache_purge(cd); 1818 cache_unregister_net(cd, net); 1819 cache_destroy_net(cd, net); 1820} 1821 1822int 1823gss_svc_init_net(struct net *net) 1824{ 1825 int rv; 1826 1827 rv = rsc_cache_create_net(net); 1828 if (rv) 1829 return rv; 1830 rv = rsi_cache_create_net(net); 1831 if (rv) 1832 goto out1; 1833 rv = create_use_gss_proxy_proc_entry(net); 1834 if (rv) 1835 goto out2; 1836 return 0; 1837out2: 1838 destroy_use_gss_proxy_proc_entry(net); 1839out1: 1840 rsc_cache_destroy_net(net); 1841 return rv; 1842} 1843 1844void 1845gss_svc_shutdown_net(struct net *net) 1846{ 1847 destroy_use_gss_proxy_proc_entry(net); 1848 rsi_cache_destroy_net(net); 1849 rsc_cache_destroy_net(net); 1850} 1851 1852int 1853gss_svc_init(void) 1854{ 1855 return svc_auth_register(RPC_AUTH_GSS, &svcauthops_gss); 1856} 1857 1858void 1859gss_svc_shutdown(void) 1860{ 1861 svc_auth_unregister(RPC_AUTH_GSS); 1862} 1863