net/xfrm/xfrm_user.c

   1 /* xfrm_user.c: User interface to configure xfrm engine.
   2  *
   3  * Copyright (C) 2002 David S. Miller (davem@redhat.com)
   4  *
   5  * Changes:
   6  *      Mitsuru KANDA @USAGI
   7  *      Kazunori MIYAZAWA @USAGI
   8  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   9  *              IPv6 support
  10  *
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/types.h>
  16 #include <linux/slab.h>
  17 #include <linux/socket.h>
  18 #include <linux/string.h>
  19 #include <linux/net.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/netlink.h>
  22 #include <linux/rtnetlink.h>
  23 #include <linux/pfkeyv2.h>
  24 #include <linux/ipsec.h>
  25 #include <linux/init.h>
  26 #include <linux/security.h>
  27 #include <net/sock.h>
  28 #include <net/xfrm.h>
  29 #include <asm/uaccess.h>
  30
  31 static struct sock *xfrm_nl;
  32
  33 static int verify_one_alg(struct rtattr **xfrma, enum xfrm_attr_type_t type)
  34 {
  35         struct rtattr *rt = xfrma[type - 1];
  36         struct xfrm_algo *algp;
  37
  38         if (!rt)
  39                 return 0;
  40
  41         if ((rt->rta_len - sizeof(*rt)) < sizeof(*algp))
  42                 return -EINVAL;
  43
  44         algp = RTA_DATA(rt);
  45         switch (type) {
  46         case XFRMA_ALG_AUTH:
  47                 if (!algp->alg_key_len &&
  48                     strcmp(algp->alg_name, "digest_null") != 0)
  49                         return -EINVAL;
  50                 break;
  51
  52         case XFRMA_ALG_CRYPT:
  53                 if (!algp->alg_key_len &&
  54                     strcmp(algp->alg_name, "cipher_null") != 0)
  55                         return -EINVAL;
  56                 break;
  57
  58         case XFRMA_ALG_COMP:
  59                 /* Zero length keys are legal.  */
  60                 break;
  61
  62         default:
  63                 return -EINVAL;
  64         };
  65
  66         algp->alg_name[CRYPTO_MAX_ALG_NAME - 1] = '\0';
  67         return 0;
  68 }
  69
  70 static int verify_encap_tmpl(struct rtattr **xfrma)
  71 {
  72         struct rtattr *rt = xfrma[XFRMA_ENCAP - 1];
  73         struct xfrm_encap_tmpl *encap;
  74
  75         if (!rt)
  76                 return 0;
  77
  78         if ((rt->rta_len - sizeof(*rt)) < sizeof(*encap))
  79                 return -EINVAL;
  80
  81         return 0;
  82 }
  83
  84 static int verify_newsa_info(struct xfrm_usersa_info *p,
  85                              struct rtattr **xfrma)
  86 {
  87         int err;
  88
  89         err = -EINVAL;
  90         switch (p->family) {
  91         case AF_INET:
  92                 break;
  93
  94         case AF_INET6:
  95 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  96                 break;
  97 #else
  98                 err = -EAFNOSUPPORT;
  99                 goto out;
 100 #endif
 101
 102         default:
 103                 goto out;
 104         };
 105
 106         err = -EINVAL;
 107         switch (p->id.proto) {
 108         case IPPROTO_AH:
 109                 if (!xfrma[XFRMA_ALG_AUTH-1]    ||
 110                     xfrma[XFRMA_ALG_CRYPT-1]    ||
 111                     xfrma[XFRMA_ALG_COMP-1])
 112                         goto out;
 113                 break;
 114
 115         case IPPROTO_ESP:
 116                 if ((!xfrma[XFRMA_ALG_AUTH-1] &&
 117                      !xfrma[XFRMA_ALG_CRYPT-1]) ||
 118                     xfrma[XFRMA_ALG_COMP-1])
 119                         goto out;
 120                 break;
 121
 122         case IPPROTO_COMP:
 123                 if (!xfrma[XFRMA_ALG_COMP-1]    ||
 124                     xfrma[XFRMA_ALG_AUTH-1]     ||
 125                     xfrma[XFRMA_ALG_CRYPT-1])
 126                         goto out;
 127                 break;
 128
 129         default:
 130                 goto out;
 131         };
 132
 133         if ((err = verify_one_alg(xfrma, XFRMA_ALG_AUTH)))
 134                 goto out;
 135         if ((err = verify_one_alg(xfrma, XFRMA_ALG_CRYPT)))
 136                 goto out;
 137         if ((err = verify_one_alg(xfrma, XFRMA_ALG_COMP)))
 138                 goto out;
 139         if ((err = verify_encap_tmpl(xfrma)))
 140                 goto out;
 141
 142         err = -EINVAL;
 143         switch (p->mode) {
 144         case 0:
 145         case 1:
 146                 break;
 147
 148         default:
 149                 goto out;
 150         };
 151
 152         err = 0;
 153
 154 out:
 155         return err;
 156 }
 157
 158 static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
 159                            struct xfrm_algo_desc *(*get_byname)(char *, int),
 160                            struct rtattr *u_arg)
 161 {
 162         struct rtattr *rta = u_arg;
 163         struct xfrm_algo *p, *ualg;
 164         struct xfrm_algo_desc *algo;
 165
 166         if (!rta)
 167                 return 0;
 168
 169         ualg = RTA_DATA(rta);
 170
 171         algo = get_byname(ualg->alg_name, 1);
 172         if (!algo)
 173                 return -ENOSYS;
 174         *props = algo->desc.sadb_alg_id;
 175
 176         p = kmalloc(sizeof(*ualg) + ualg->alg_key_len, GFP_KERNEL);
 177         if (!p)
 178                 return -ENOMEM;
 179
 180         memcpy(p, ualg, sizeof(*ualg) + ualg->alg_key_len);
 181         *algpp = p;
 182         return 0;
 183 }
 184
 185 static int attach_encap_tmpl(struct xfrm_encap_tmpl **encapp, struct rtattr *u_arg)
 186 {
 187         struct rtattr *rta = u_arg;
 188         struct xfrm_encap_tmpl *p, *uencap;
 189
 190         if (!rta)
 191                 return 0;
 192
 193         uencap = RTA_DATA(rta);
 194         p = kmalloc(sizeof(*p), GFP_KERNEL);
 195         if (!p)
 196                 return -ENOMEM;
 197
 198         memcpy(p, uencap, sizeof(*p));
 199         *encapp = p;
 200         return 0;
 201 }
 202
 203 static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
 204 {
 205         memcpy(&x->id, &p->id, sizeof(x->id));
 206         memcpy(&x->sel, &p->sel, sizeof(x->sel));
 207         memcpy(&x->lft, &p->lft, sizeof(x->lft));
 208         x->props.mode = p->mode;
 209         x->props.replay_window = p->replay_window;
 210         x->props.reqid = p->reqid;
 211         x->props.family = p->family;
 212         x->props.saddr = p->saddr;
 213         x->props.flags = p->flags;
 214 }
 215
 216 static struct xfrm_state *xfrm_state_construct(struct xfrm_usersa_info *p,
 217                                                struct rtattr **xfrma,
 218                                                int *errp)
 219 {
 220         struct xfrm_state *x = xfrm_state_alloc();
 221         int err = -ENOMEM;
 222
 223         if (!x)
 224                 goto error_no_put;
 225
 226         copy_from_user_state(x, p);
 227
 228         if ((err = attach_one_algo(&x->aalg, &x->props.aalgo,
 229                                    xfrm_aalg_get_byname,
 230                                    xfrma[XFRMA_ALG_AUTH-1])))
 231                 goto error;
 232         if ((err = attach_one_algo(&x->ealg, &x->props.ealgo,
 233                                    xfrm_ealg_get_byname,
 234                                    xfrma[XFRMA_ALG_CRYPT-1])))
 235                 goto error;
 236         if ((err = attach_one_algo(&x->calg, &x->props.calgo,
 237                                    xfrm_calg_get_byname,
 238                                    xfrma[XFRMA_ALG_COMP-1])))
 239                 goto error;
 240         if ((err = attach_encap_tmpl(&x->encap, xfrma[XFRMA_ENCAP-1])))
 241                 goto error;
 242
 243         err = -ENOENT;
 244         x->type = xfrm_get_type(x->id.proto, x->props.family);
 245         if (x->type == NULL)
 246                 goto error;
 247
 248         err = x->type->init_state(x, NULL);
 249         if (err)
 250                 goto error;
 251
 252         x->curlft.add_time = (unsigned long) xtime.tv_sec;
 253         x->km.state = XFRM_STATE_VALID;
 254         x->km.seq = p->seq;
 255
 256         return x;
 257
 258 error:
 259         x->km.state = XFRM_STATE_DEAD;
 260         xfrm_state_put(x);
 261 error_no_put:
 262         *errp = err;
 263         return NULL;
 264 }
 265
 266 static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 267 {
 268         struct xfrm_usersa_info *p = NLMSG_DATA(nlh);
 269         struct xfrm_state *x;
 270         int err;
 271
 272         err = verify_newsa_info(p, (struct rtattr **) xfrma);
 273         if (err)
 274                 return err;
 275
 276         x = xfrm_state_construct(p, (struct rtattr **) xfrma, &err);
 277         if (!x)
 278                 return err;
 279
 280         if (nlh->nlmsg_type == XFRM_MSG_NEWSA)
 281                 err = xfrm_state_add(x);
 282         else
 283                 err = xfrm_state_update(x);
 284
 285         if (err < 0) {
 286                 x->km.state = XFRM_STATE_DEAD;
 287                 xfrm_state_put(x);
 288         }
 289
 290         return err;
 291 }
 292
 293 static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 294 {
 295         struct xfrm_state *x;
 296         struct xfrm_usersa_id *p = NLMSG_DATA(nlh);
 297
 298         x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
 299         if (x == NULL)
 300                 return -ESRCH;
 301
 302         if (xfrm_state_kern(x)) {
 303                 xfrm_state_put(x);
 304                 return -EPERM;
 305         }
 306
 307         xfrm_state_delete(x);
 308         xfrm_state_put(x);
 309
 310         return 0;
 311 }
 312
 313 static void copy_to_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
 314 {
 315         memcpy(&p->id, &x->id, sizeof(p->id));
 316         memcpy(&p->sel, &x->sel, sizeof(p->sel));
 317         memcpy(&p->lft, &x->lft, sizeof(p->lft));
 318         memcpy(&p->curlft, &x->curlft, sizeof(p->curlft));
 319         memcpy(&p->stats, &x->stats, sizeof(p->stats));
 320         p->saddr = x->props.saddr;
 321         p->mode = x->props.mode;
 322         p->replay_window = x->props.replay_window;
 323         p->reqid = x->props.reqid;
 324         p->family = x->props.family;
 325         p->flags = x->props.flags;
 326         p->seq = x->km.seq;
 327 }
 328
 329 struct xfrm_dump_info {
 330         struct sk_buff *in_skb;
 331         struct sk_buff *out_skb;
 332         u32 nlmsg_seq;
 333         u16 nlmsg_flags;
 334         int start_idx;
 335         int this_idx;
 336 };
 337
 338 static int dump_one_state(struct xfrm_state *x, int count, void *ptr)
 339 {
 340         struct xfrm_dump_info *sp = ptr;
 341         struct sk_buff *in_skb = sp->in_skb;
 342         struct sk_buff *skb = sp->out_skb;
 343         struct xfrm_usersa_info *p;
 344         struct nlmsghdr *nlh;
 345         unsigned char *b = skb->tail;
 346
 347         if (sp->this_idx < sp->start_idx)
 348                 goto out;
 349
 350         nlh = NLMSG_PUT(skb, NETLINK_CB(in_skb).pid,
 351                         sp->nlmsg_seq,
 352                         XFRM_MSG_NEWSA, sizeof(*p));
 353         nlh->nlmsg_flags = sp->nlmsg_flags;
 354
 355         p = NLMSG_DATA(nlh);
 356         copy_to_user_state(x, p);
 357
 358         if (x->aalg)
 359                 RTA_PUT(skb, XFRMA_ALG_AUTH,
 360                         sizeof(*(x->aalg))+(x->aalg->alg_key_len+7)/8, x->aalg);
 361         if (x->ealg)
 362                 RTA_PUT(skb, XFRMA_ALG_CRYPT,
 363                         sizeof(*(x->ealg))+(x->ealg->alg_key_len+7)/8, x->ealg);
 364         if (x->calg)
 365                 RTA_PUT(skb, XFRMA_ALG_COMP, sizeof(*(x->calg)), x->calg);
 366
 367         if (x->encap)
 368                 RTA_PUT(skb, XFRMA_ENCAP, sizeof(*x->encap), x->encap);
 369
 370         nlh->nlmsg_len = skb->tail - b;
 371 out:
 372         sp->this_idx++;
 373         return 0;
 374
 375 nlmsg_failure:
 376 rtattr_failure:
 377         skb_trim(skb, b - skb->data);
 378         return -1;
 379 }
 380
 381 static int xfrm_dump_sa(struct sk_buff *skb, struct netlink_callback *cb)
 382 {
 383         struct xfrm_dump_info info;
 384
 385         info.in_skb = cb->skb;
 386         info.out_skb = skb;
 387         info.nlmsg_seq = cb->nlh->nlmsg_seq;
 388         info.nlmsg_flags = NLM_F_MULTI;
 389         info.this_idx = 0;
 390         info.start_idx = cb->args[0];
 391         (void) xfrm_state_walk(IPSEC_PROTO_ANY, dump_one_state, &info);
 392         cb->args[0] = info.this_idx;
 393
 394         return skb->len;
 395 }
 396
 397 static struct sk_buff *xfrm_state_netlink(struct sk_buff *in_skb,
 398                                           struct xfrm_state *x, u32 seq)
 399 {
 400         struct xfrm_dump_info info;
 401         struct sk_buff *skb;
 402
 403         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
 404         if (!skb)
 405                 return ERR_PTR(-ENOMEM);
 406
 407         NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
 408         info.in_skb = in_skb;
 409         info.out_skb = skb;
 410         info.nlmsg_seq = seq;
 411         info.nlmsg_flags = 0;
 412         info.this_idx = info.start_idx = 0;
 413
 414         if (dump_one_state(x, 0, &info)) {
 415                 kfree_skb(skb);
 416                 return NULL;
 417         }
 418
 419         return skb;
 420 }
 421
 422 static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 423 {
 424         struct xfrm_usersa_id *p = NLMSG_DATA(nlh);
 425         struct xfrm_state *x;
 426         struct sk_buff *resp_skb;
 427         int err;
 428
 429         x = xfrm_state_lookup(&p->daddr, p->spi, p->proto, p->family);
 430         err = -ESRCH;
 431         if (x == NULL)
 432                 goto out_noput;
 433
 434         resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
 435         if (IS_ERR(resp_skb)) {
 436                 err = PTR_ERR(resp_skb);
 437         } else {
 438                 err = netlink_unicast(xfrm_nl, resp_skb,
 439                                       NETLINK_CB(skb).pid, MSG_DONTWAIT);
 440         }
 441         xfrm_state_put(x);
 442 out_noput:
 443         return err;
 444 }
 445
 446 static int verify_userspi_info(struct xfrm_userspi_info *p)
 447 {
 448         switch (p->info.id.proto) {
 449         case IPPROTO_AH:
 450         case IPPROTO_ESP:
 451                 break;
 452
 453         case IPPROTO_COMP:
 454                 /* IPCOMP spi is 16-bits. */
 455                 if (p->max >= 0x10000)
 456                         return -EINVAL;
 457                 break;
 458
 459         default:
 460                 return -EINVAL;
 461         };
 462
 463         if (p->min > p->max)
 464                 return -EINVAL;
 465
 466         return 0;
 467 }
 468
 469 static int xfrm_alloc_userspi(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 470 {
 471         struct xfrm_state *x;
 472         struct xfrm_userspi_info *p;
 473         struct sk_buff *resp_skb;
 474         xfrm_address_t *daddr;
 475         int family;
 476         int err;
 477
 478         p = NLMSG_DATA(nlh);
 479         err = verify_userspi_info(p);
 480         if (err)
 481                 goto out_noput;
 482
 483         family = p->info.family;
 484         daddr = &p->info.id.daddr;
 485
 486         x = NULL;
 487         if (p->info.seq) {
 488                 x = xfrm_find_acq_byseq(p->info.seq);
 489                 if (x && xfrm_addr_cmp(&x->id.daddr, daddr, family)) {
 490                         xfrm_state_put(x);
 491                         x = NULL;
 492                 }
 493         }
 494
 495         if (!x)
 496                 x = xfrm_find_acq(p->info.mode, p->info.reqid,
 497                                   p->info.id.proto, daddr,
 498                                   &p->info.saddr, 1,
 499                                   family);
 500         err = -ENOENT;
 501         if (x == NULL)
 502                 goto out_noput;
 503
 504         resp_skb = ERR_PTR(-ENOENT);
 505
 506         spin_lock_bh(&x->lock);
 507         if (x->km.state != XFRM_STATE_DEAD) {
 508                 xfrm_alloc_spi(x, htonl(p->min), htonl(p->max));
 509                 if (x->id.spi)
 510                         resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
 511         }
 512         spin_unlock_bh(&x->lock);
 513
 514         if (IS_ERR(resp_skb)) {
 515                 err = PTR_ERR(resp_skb);
 516                 goto out;
 517         }
 518
 519         err = netlink_unicast(xfrm_nl, resp_skb,
 520                               NETLINK_CB(skb).pid, MSG_DONTWAIT);
 521
 522 out:
 523         xfrm_state_put(x);
 524 out_noput:
 525         return err;
 526 }
 527
 528 static int verify_policy_dir(__u8 dir)
 529 {
 530         switch (dir) {
 531         case XFRM_POLICY_IN:
 532         case XFRM_POLICY_OUT:
 533         case XFRM_POLICY_FWD:
 534                 break;
 535
 536         default:
 537                 return -EINVAL;
 538         };
 539
 540         return 0;
 541 }
 542
 543 static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
 544 {
 545         switch (p->share) {
 546         case XFRM_SHARE_ANY:
 547         case XFRM_SHARE_SESSION:
 548         case XFRM_SHARE_USER:
 549         case XFRM_SHARE_UNIQUE:
 550                 break;
 551
 552         default:
 553                 return -EINVAL;
 554         };
 555
 556         switch (p->action) {
 557         case XFRM_POLICY_ALLOW:
 558         case XFRM_POLICY_BLOCK:
 559                 break;
 560
 561         default:
 562                 return -EINVAL;
 563         };
 564
 565         switch (p->sel.family) {
 566         case AF_INET:
 567                 break;
 568
 569         case AF_INET6:
 570 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 571                 break;
 572 #else
 573                 return  -EAFNOSUPPORT;
 574 #endif
 575
 576         default:
 577                 return -EINVAL;
 578         };
 579
 580         return verify_policy_dir(p->dir);
 581 }
 582
 583 static void copy_templates(struct xfrm_policy *xp, struct xfrm_user_tmpl *ut,
 584                            int nr)
 585 {
 586         int i;
 587
 588         xp->xfrm_nr = nr;
 589         for (i = 0; i < nr; i++, ut++) {
 590                 struct xfrm_tmpl *t = &xp->xfrm_vec[i];
 591
 592                 memcpy(&t->id, &ut->id, sizeof(struct xfrm_id));
 593                 memcpy(&t->saddr, &ut->saddr,
 594                        sizeof(xfrm_address_t));
 595                 t->reqid = ut->reqid;
 596                 t->mode = ut->mode;
 597                 t->share = ut->share;
 598                 t->optional = ut->optional;
 599                 t->aalgos = ut->aalgos;
 600                 t->ealgos = ut->ealgos;
 601                 t->calgos = ut->calgos;
 602         }
 603 }
 604
 605 static int copy_from_user_tmpl(struct xfrm_policy *pol, struct rtattr **xfrma)
 606 {
 607         struct rtattr *rt = xfrma[XFRMA_TMPL-1];
 608         struct xfrm_user_tmpl *utmpl;
 609         int nr;
 610
 611         if (!rt) {
 612                 pol->xfrm_nr = 0;
 613         } else {
 614                 nr = (rt->rta_len - sizeof(*rt)) / sizeof(*utmpl);
 615
 616                 if (nr > XFRM_MAX_DEPTH)
 617                         return -EINVAL;
 618
 619                 copy_templates(pol, RTA_DATA(rt), nr);
 620         }
 621         return 0;
 622 }
 623
 624 static void copy_from_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p)
 625 {
 626         xp->priority = p->priority;
 627         xp->index = p->index;
 628         memcpy(&xp->selector, &p->sel, sizeof(xp->selector));
 629         memcpy(&xp->lft, &p->lft, sizeof(xp->lft));
 630         xp->action = p->action;
 631         xp->flags = p->flags;
 632         xp->family = p->sel.family;
 633         /* XXX xp->share = p->share; */
 634 }
 635
 636 static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p, int dir)
 637 {
 638         memcpy(&p->sel, &xp->selector, sizeof(p->sel));
 639         memcpy(&p->lft, &xp->lft, sizeof(p->lft));
 640         memcpy(&p->curlft, &xp->curlft, sizeof(p->curlft));
 641         p->priority = xp->priority;
 642         p->index = xp->index;
 643         p->sel.family = xp->family;
 644         p->dir = dir;
 645         p->action = xp->action;
 646         p->flags = xp->flags;
 647         p->share = XFRM_SHARE_ANY; /* XXX xp->share */
 648 }
 649
 650 static struct xfrm_policy *xfrm_policy_construct(struct xfrm_userpolicy_info *p, struct rtattr **xfrma, int *errp)
 651 {
 652         struct xfrm_policy *xp = xfrm_policy_alloc(GFP_KERNEL);
 653         int err;
 654
 655         if (!xp) {
 656                 *errp = -ENOMEM;
 657                 return NULL;
 658         }
 659
 660         copy_from_user_policy(xp, p);
 661         err = copy_from_user_tmpl(xp, xfrma);
 662         if (err) {
 663                 *errp = err;
 664                 kfree(xp);
 665                 xp = NULL;
 666         }
 667
 668         return xp;
 669 }
 670
 671 static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 672 {
 673         struct xfrm_userpolicy_info *p = NLMSG_DATA(nlh);
 674         struct xfrm_policy *xp;
 675         int err;
 676         int excl;
 677
 678         err = verify_newpolicy_info(p);
 679         if (err)
 680                 return err;
 681
 682         xp = xfrm_policy_construct(p, (struct rtattr **) xfrma, &err);
 683         if (!xp)
 684                 return err;
 685
 686         excl = nlh->nlmsg_type == XFRM_MSG_NEWPOLICY;
 687         err = xfrm_policy_insert(p->dir, xp, excl);
 688         if (err) {
 689                 kfree(xp);
 690                 return err;
 691         }
 692
 693         xfrm_pol_put(xp);
 694
 695         return 0;
 696 }
 697
 698 static int copy_to_user_tmpl(struct xfrm_policy *xp, struct sk_buff *skb)
 699 {
 700         struct xfrm_user_tmpl vec[XFRM_MAX_DEPTH];
 701         int i;
 702
 703         if (xp->xfrm_nr == 0)
 704                 return 0;
 705
 706         for (i = 0; i < xp->xfrm_nr; i++) {
 707                 struct xfrm_user_tmpl *up = &vec[i];
 708                 struct xfrm_tmpl *kp = &xp->xfrm_vec[i];
 709
 710                 memcpy(&up->id, &kp->id, sizeof(up->id));
 711                 up->family = xp->family;
 712                 memcpy(&up->saddr, &kp->saddr, sizeof(up->saddr));
 713                 up->reqid = kp->reqid;
 714                 up->mode = kp->mode;
 715                 up->share = kp->share;
 716                 up->optional = kp->optional;
 717                 up->aalgos = kp->aalgos;
 718                 up->ealgos = kp->ealgos;
 719                 up->calgos = kp->calgos;
 720         }
 721         RTA_PUT(skb, XFRMA_TMPL,
 722                 (sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr),
 723                 vec);
 724
 725         return 0;
 726
 727 rtattr_failure:
 728         return -1;
 729 }
 730
 731 static int dump_one_policy(struct xfrm_policy *xp, int dir, int count, void *ptr)
 732 {
 733         struct xfrm_dump_info *sp = ptr;
 734         struct xfrm_userpolicy_info *p;
 735         struct sk_buff *in_skb = sp->in_skb;
 736         struct sk_buff *skb = sp->out_skb;
 737         struct nlmsghdr *nlh;
 738         unsigned char *b = skb->tail;
 739
 740         if (sp->this_idx < sp->start_idx)
 741                 goto out;
 742
 743         nlh = NLMSG_PUT(skb, NETLINK_CB(in_skb).pid,
 744                         sp->nlmsg_seq,
 745                         XFRM_MSG_NEWPOLICY, sizeof(*p));
 746         p = NLMSG_DATA(nlh);
 747         nlh->nlmsg_flags = sp->nlmsg_flags;
 748
 749         copy_to_user_policy(xp, p, dir);
 750         if (copy_to_user_tmpl(xp, skb) < 0)
 751                 goto nlmsg_failure;
 752
 753         nlh->nlmsg_len = skb->tail - b;
 754 out:
 755         sp->this_idx++;
 756         return 0;
 757
 758 nlmsg_failure:
 759         skb_trim(skb, b - skb->data);
 760         return -1;
 761 }
 762
 763 static int xfrm_dump_policy(struct sk_buff *skb, struct netlink_callback *cb)
 764 {
 765         struct xfrm_dump_info info;
 766
 767         info.in_skb = cb->skb;
 768         info.out_skb = skb;
 769         info.nlmsg_seq = cb->nlh->nlmsg_seq;
 770         info.nlmsg_flags = NLM_F_MULTI;
 771         info.this_idx = 0;
 772         info.start_idx = cb->args[0];
 773         (void) xfrm_policy_walk(dump_one_policy, &info);
 774         cb->args[0] = info.this_idx;
 775
 776         return skb->len;
 777 }
 778
 779 static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
 780                                           struct xfrm_policy *xp,
 781                                           int dir, u32 seq)
 782 {
 783         struct xfrm_dump_info info;
 784         struct sk_buff *skb;
 785
 786         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 787         if (!skb)
 788                 return ERR_PTR(-ENOMEM);
 789
 790         NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid;
 791         info.in_skb = in_skb;
 792         info.out_skb = skb;
 793         info.nlmsg_seq = seq;
 794         info.nlmsg_flags = 0;
 795         info.this_idx = info.start_idx = 0;
 796
 797         if (dump_one_policy(xp, dir, 0, &info) < 0) {
 798                 kfree_skb(skb);
 799                 return NULL;
 800         }
 801
 802         return skb;
 803 }
 804
 805 static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 806 {
 807         struct xfrm_policy *xp;
 808         struct xfrm_userpolicy_id *p;
 809         int err;
 810         int delete;
 811
 812         p = NLMSG_DATA(nlh);
 813         delete = nlh->nlmsg_type == XFRM_MSG_DELPOLICY;
 814
 815         err = verify_policy_dir(p->dir);
 816         if (err)
 817                 return err;
 818
 819         if (p->index)
 820                 xp = xfrm_policy_byid(p->dir, p->index, delete);
 821         else
 822                 xp = xfrm_policy_bysel(p->dir, &p->sel, delete);
 823         if (xp == NULL)
 824                 return -ENOENT;
 825
 826         if (!delete) {
 827                 struct sk_buff *resp_skb;
 828
 829                 resp_skb = xfrm_policy_netlink(skb, xp, p->dir, nlh->nlmsg_seq);
 830                 if (IS_ERR(resp_skb)) {
 831                         err = PTR_ERR(resp_skb);
 832                 } else {
 833                         err = netlink_unicast(xfrm_nl, resp_skb,
 834                                               NETLINK_CB(skb).pid,
 835                                               MSG_DONTWAIT);
 836                 }
 837         }
 838
 839         xfrm_pol_put(xp);
 840
 841         return err;
 842 }
 843
 844 static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 845 {
 846         struct xfrm_usersa_flush *p = NLMSG_DATA(nlh);
 847
 848         xfrm_state_flush(p->proto);
 849         return 0;
 850 }
 851
 852 static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh, void **xfrma)
 853 {
 854         xfrm_policy_flush();
 855         return 0;
 856 }
 857
 858 static const int xfrm_msg_min[(XFRM_MSG_MAX + 1 - XFRM_MSG_BASE)] = {
 859         NLMSG_LENGTH(sizeof(struct xfrm_usersa_info)),  /* NEW SA */
 860         NLMSG_LENGTH(sizeof(struct xfrm_usersa_id)),    /* DEL SA */
 861         NLMSG_LENGTH(sizeof(struct xfrm_usersa_id)),    /* GET SA */
 862         NLMSG_LENGTH(sizeof(struct xfrm_userpolicy_info)),/* NEW POLICY */
 863         NLMSG_LENGTH(sizeof(struct xfrm_userpolicy_id)),  /* DEL POLICY */
 864         NLMSG_LENGTH(sizeof(struct xfrm_userpolicy_id)),  /* GET POLICY */
 865         NLMSG_LENGTH(sizeof(struct xfrm_userspi_info)), /* ALLOC SPI */
 866         NLMSG_LENGTH(sizeof(struct xfrm_user_acquire)), /* ACQUIRE */
 867         NLMSG_LENGTH(sizeof(struct xfrm_user_expire)),  /* EXPIRE */
 868         NLMSG_LENGTH(sizeof(struct xfrm_userpolicy_info)),/* UPD POLICY */
 869         NLMSG_LENGTH(sizeof(struct xfrm_usersa_info)),  /* UPD SA */
 870         NLMSG_LENGTH(sizeof(struct xfrm_user_polexpire)), /* POLEXPIRE */
 871         NLMSG_LENGTH(sizeof(struct xfrm_usersa_flush)), /* FLUSH SA */
 872         NLMSG_LENGTH(0),                                /* FLUSH POLICY */
 873 };
 874
 875 static struct xfrm_link {
 876         int (*doit)(struct sk_buff *, struct nlmsghdr *, void **);
 877         int (*dump)(struct sk_buff *, struct netlink_callback *);
 878 } xfrm_dispatch[] = {
 879         {       .doit   =       xfrm_add_sa,            },
 880         {       .doit   =       xfrm_del_sa,            },
 881         {
 882                 .doit   =       xfrm_get_sa,
 883                 .dump   =       xfrm_dump_sa,
 884         },
 885         {       .doit   =       xfrm_add_policy         },
 886         {       .doit   =       xfrm_get_policy         },
 887         {
 888                 .doit   =       xfrm_get_policy,
 889                 .dump   =       xfrm_dump_policy,
 890         },
 891         {       .doit   =       xfrm_alloc_userspi      },
 892         {},
 893         {},
 894         {       .doit   =       xfrm_add_policy         },
 895         {       .doit   =       xfrm_add_sa,            },
 896         {},
 897         {       .doit   =       xfrm_flush_sa           },
 898         {       .doit   =       xfrm_flush_policy       },
 899 };
 900
 901 static int xfrm_done(struct netlink_callback *cb)
 902 {
 903         return 0;
 904 }
 905
 906 static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp)
 907 {
 908         struct rtattr *xfrma[XFRMA_MAX];
 909         struct xfrm_link *link;
 910         int type, min_len;
 911
 912         if (!(nlh->nlmsg_flags & NLM_F_REQUEST))
 913                 return 0;
 914
 915         type = nlh->nlmsg_type;
 916
 917         /* A control message: ignore them */
 918         if (type < XFRM_MSG_BASE)
 919                 return 0;
 920
 921         /* Unknown message: reply with EINVAL */
 922         if (type > XFRM_MSG_MAX)
 923                 goto err_einval;
 924
 925         type -= XFRM_MSG_BASE;
 926         link = &xfrm_dispatch[type];
 927
 928         /* All operations require privileges, even GET */
 929         if (security_netlink_recv(skb)) {
 930                 *errp = -EPERM;
 931                 return -1;
 932         }
 933
 934         if ((type == 2 || type == 5) && (nlh->nlmsg_flags & NLM_F_DUMP)) {
 935                 u32 rlen;
 936
 937                 if (link->dump == NULL)
 938                         goto err_einval;
 939
 940                 if ((*errp = netlink_dump_start(xfrm_nl, skb, nlh,
 941                                                 link->dump,
 942                                                 xfrm_done)) != 0) {
 943                         return -1;
 944                 }
 945                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 946                 if (rlen > skb->len)
 947                         rlen = skb->len;
 948                 skb_pull(skb, rlen);
 949                 return -1;
 950         }
 951
 952         memset(xfrma, 0, sizeof(xfrma));
 953
 954         if (nlh->nlmsg_len < (min_len = xfrm_msg_min[type]))
 955                 goto err_einval;
 956
 957         if (nlh->nlmsg_len > min_len) {
 958                 int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
 959                 struct rtattr *attr = (void *) nlh + NLMSG_ALIGN(min_len);
 960
 961                 while (RTA_OK(attr, attrlen)) {
 962                         unsigned short flavor = attr->rta_type;
 963                         if (flavor) {
 964                                 if (flavor > XFRMA_MAX)
 965                                         goto err_einval;
 966                                 xfrma[flavor - 1] = attr;
 967                         }
 968                         attr = RTA_NEXT(attr, attrlen);
 969                 }
 970         }
 971
 972         if (link->doit == NULL)
 973                 goto err_einval;
 974         *errp = link->doit(skb, nlh, (void **) &xfrma);
 975
 976         return *errp;
 977
 978 err_einval:
 979         *errp = -EINVAL;
 980         return -1;
 981 }
 982
 983 static int xfrm_user_rcv_skb(struct sk_buff *skb)
 984 {
 985         int err;
 986         struct nlmsghdr *nlh;
 987
 988         while (skb->len >= NLMSG_SPACE(0)) {
 989                 u32 rlen;
 990
 991                 nlh = (struct nlmsghdr *) skb->data;
 992                 if (nlh->nlmsg_len < sizeof(*nlh) ||
 993                     skb->len < nlh->nlmsg_len)
 994                         return 0;
 995                 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
 996                 if (rlen > skb->len)
 997                         rlen = skb->len;
 998                 if (xfrm_user_rcv_msg(skb, nlh, &err) < 0) {
 999                         if (err == 0)
1000                                 return -1;
1001                         netlink_ack(skb, nlh, err);
1002                 } else if (nlh->nlmsg_flags & NLM_F_ACK)
1003                         netlink_ack(skb, nlh, 0);
1004                 skb_pull(skb, rlen);
1005         }
1006
1007         return 0;
1008 }
1009
1010 static void xfrm_netlink_rcv(struct sock *sk, int len)
1011 {
1012         do {
1013                 struct sk_buff *skb;
1014
1015                 down(&xfrm_cfg_sem);
1016
1017                 while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
1018                         if (xfrm_user_rcv_skb(skb)) {
1019                                 if (skb->len)
1020                                         skb_queue_head(&sk->sk_receive_queue,
1021                                                        skb);
1022                                 else
1023                                         kfree_skb(skb);
1024                                 break;
1025                         }
1026                         kfree_skb(skb);
1027                 }
1028
1029                 up(&xfrm_cfg_sem);
1030
1031         } while (xfrm_nl && xfrm_nl->sk_receive_queue.qlen);
1032 }
1033
1034 static int build_expire(struct sk_buff *skb, struct xfrm_state *x, int hard)
1035 {
1036         struct xfrm_user_expire *ue;
1037         struct nlmsghdr *nlh;
1038         unsigned char *b = skb->tail;
1039
1040         nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_EXPIRE,
1041                         sizeof(*ue));
1042         ue = NLMSG_DATA(nlh);
1043         nlh->nlmsg_flags = 0;
1044
1045         copy_to_user_state(x, &ue->state);
1046         ue->hard = (hard != 0) ? 1 : 0;
1047
1048         nlh->nlmsg_len = skb->tail - b;
1049         return skb->len;
1050
1051 nlmsg_failure:
1052         skb_trim(skb, b - skb->data);
1053         return -1;
1054 }
1055
1056 static int xfrm_send_state_notify(struct xfrm_state *x, int hard)
1057 {
1058         struct sk_buff *skb;
1059
1060         skb = alloc_skb(sizeof(struct xfrm_user_expire) + 16, GFP_ATOMIC);
1061         if (skb == NULL)
1062                 return -ENOMEM;
1063
1064         if (build_expire(skb, x, hard) < 0)
1065                 BUG();
1066
1067         NETLINK_CB(skb).dst_groups = XFRMGRP_EXPIRE;
1068
1069         return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_EXPIRE, GFP_ATOMIC);
1070 }
1071
1072 static int build_acquire(struct sk_buff *skb, struct xfrm_state *x,
1073                          struct xfrm_tmpl *xt, struct xfrm_policy *xp,
1074                          int dir)
1075 {
1076         struct xfrm_user_acquire *ua;
1077         struct nlmsghdr *nlh;
1078         unsigned char *b = skb->tail;
1079         __u32 seq = xfrm_get_acqseq();
1080
1081         nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_ACQUIRE,
1082                         sizeof(*ua));
1083         ua = NLMSG_DATA(nlh);
1084         nlh->nlmsg_flags = 0;
1085
1086         memcpy(&ua->id, &x->id, sizeof(ua->id));
1087         memcpy(&ua->saddr, &x->props.saddr, sizeof(ua->saddr));
1088         memcpy(&ua->sel, &x->sel, sizeof(ua->sel));
1089         copy_to_user_policy(xp, &ua->policy, dir);
1090         ua->aalgos = xt->aalgos;
1091         ua->ealgos = xt->ealgos;
1092         ua->calgos = xt->calgos;
1093         ua->seq = x->km.seq = seq;
1094
1095         if (copy_to_user_tmpl(xp, skb) < 0)
1096                 goto nlmsg_failure;
1097
1098         nlh->nlmsg_len = skb->tail - b;
1099         return skb->len;
1100
1101 nlmsg_failure:
1102         skb_trim(skb, b - skb->data);
1103         return -1;
1104 }
1105
1106 static int xfrm_send_acquire(struct xfrm_state *x, struct xfrm_tmpl *xt,
1107                              struct xfrm_policy *xp, int dir)
1108 {
1109         struct sk_buff *skb;
1110         size_t len;
1111
1112         len = RTA_SPACE(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr);
1113         len += NLMSG_SPACE(sizeof(struct xfrm_user_acquire));
1114         skb = alloc_skb(len, GFP_ATOMIC);
1115         if (skb == NULL)
1116                 return -ENOMEM;
1117
1118         if (build_acquire(skb, x, xt, xp, dir) < 0)
1119                 BUG();
1120
1121         NETLINK_CB(skb).dst_groups = XFRMGRP_ACQUIRE;
1122
1123         return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_ACQUIRE, GFP_ATOMIC);
1124 }
1125
1126 /* User gives us xfrm_user_policy_info followed by an array of 0
1127  * or more templates.
1128  */
1129 static struct xfrm_policy *xfrm_compile_policy(u16 family, int opt,
1130                                                u8 *data, int len, int *dir)
1131 {
1132         struct xfrm_userpolicy_info *p = (struct xfrm_userpolicy_info *)data;
1133         struct xfrm_user_tmpl *ut = (struct xfrm_user_tmpl *) (p + 1);
1134         struct xfrm_policy *xp;
1135         int nr;
1136
1137         switch (family) {
1138         case AF_INET:
1139                 if (opt != IP_XFRM_POLICY) {
1140                         *dir = -EOPNOTSUPP;
1141                         return NULL;
1142                 }
1143                 break;
1144 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1145         case AF_INET6:
1146                 if (opt != IPV6_XFRM_POLICY) {
1147                         *dir = -EOPNOTSUPP;
1148                         return NULL;
1149                 }
1150                 break;
1151 #endif
1152         default:
1153                 *dir = -EINVAL;
1154                 return NULL;
1155         }
1156
1157         *dir = -EINVAL;
1158
1159         if (len < sizeof(*p) ||
1160             verify_newpolicy_info(p))
1161                 return NULL;
1162
1163         nr = ((len - sizeof(*p)) / sizeof(*ut));
1164         if (nr > XFRM_MAX_DEPTH)
1165                 return NULL;
1166
1167         xp = xfrm_policy_alloc(GFP_KERNEL);
1168         if (xp == NULL) {
1169                 *dir = -ENOBUFS;
1170                 return NULL;
1171         }
1172
1173         copy_from_user_policy(xp, p);
1174         copy_templates(xp, ut, nr);
1175
1176         *dir = p->dir;
1177
1178         return xp;
1179 }
1180
1181 static int build_polexpire(struct sk_buff *skb, struct xfrm_policy *xp,
1182                            int dir, int hard)
1183 {
1184         struct xfrm_user_polexpire *upe;
1185         struct nlmsghdr *nlh;
1186         unsigned char *b = skb->tail;
1187
1188         nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_POLEXPIRE, sizeof(*upe));
1189         upe = NLMSG_DATA(nlh);
1190         nlh->nlmsg_flags = 0;
1191
1192         copy_to_user_policy(xp, &upe->pol, dir);
1193         if (copy_to_user_tmpl(xp, skb) < 0)
1194                 goto nlmsg_failure;
1195         upe->hard = !!hard;
1196
1197         nlh->nlmsg_len = skb->tail - b;
1198         return skb->len;
1199
1200 nlmsg_failure:
1201         skb_trim(skb, b - skb->data);
1202         return -1;
1203 }
1204
1205 static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, int hard)
1206 {
1207         struct sk_buff *skb;
1208         size_t len;
1209
1210         len = RTA_SPACE(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr);
1211         len += NLMSG_SPACE(sizeof(struct xfrm_user_polexpire));
1212         skb = alloc_skb(len, GFP_ATOMIC);
1213         if (skb == NULL)
1214                 return -ENOMEM;
1215
1216         if (build_polexpire(skb, xp, dir, hard) < 0)
1217                 BUG();
1218
1219         NETLINK_CB(skb).dst_groups = XFRMGRP_EXPIRE;
1220
1221         return netlink_broadcast(xfrm_nl, skb, 0, XFRMGRP_EXPIRE, GFP_ATOMIC);
1222 }
1223
1224 static struct xfrm_mgr netlink_mgr = {
1225         .id             = "netlink",
1226         .notify         = xfrm_send_state_notify,
1227         .acquire        = xfrm_send_acquire,
1228         .compile_policy = xfrm_compile_policy,
1229         .notify_policy  = xfrm_send_policy_notify,
1230 };
1231
1232 static int __init xfrm_user_init(void)
1233 {
1234         printk(KERN_INFO "Initializing IPsec netlink socket\n");
1235
1236         xfrm_nl = netlink_kernel_create(NETLINK_XFRM, xfrm_netlink_rcv);
1237         if (xfrm_nl == NULL)
1238                 return -ENOMEM;
1239
1240         xfrm_register_km(&netlink_mgr);
1241
1242         return 0;
1243 }
1244
1245 static void __exit xfrm_user_exit(void)
1246 {
1247         xfrm_unregister_km(&netlink_mgr);
1248         sock_release(xfrm_nl->sk_socket);
1249 }
1250
1251 module_init(xfrm_user_init);
1252 module_exit(xfrm_user_exit);
1253 MODULE_LICENSE("GPL");