sys/netproto/ncp/ncp_conn.c

   1 /*
   2  * Copyright (c) 1999, Boris Popov
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *    This product includes software developed by Boris Popov.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  * $FreeBSD: src/sys/netncp/ncp_conn.c,v 1.3.2.5 2001/02/22 08:54:11 bp Exp $
  32  * $DragonFly: src/sys/netproto/ncp/ncp_conn.c,v 1.9 2006/03/02 19:07:59 dillon Exp $
  33  *
  34  * Connection tables
  35  */
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/kernel.h>
  39 #include <sys/malloc.h>
  40 #include <sys/proc.h>
  41 #include <sys/lock.h>
  42 #include <sys/sysctl.h>
  43
  44 #include "ncp.h"
  45 #include "ncp_subr.h"
  46 #include "ncp_conn.h"
  47
  48 SLIST_HEAD(ncp_handle_head,ncp_handle);
  49
  50 int ncp_burst_enabled = 1;
  51
  52 struct ncp_conn_head conn_list={NULL};
  53 static int ncp_conn_cnt = 0;
  54 static int ncp_next_ref = 1;
  55 static struct lock listlock;
  56
  57 struct ncp_handle_head lhlist={NULL};
  58 static int ncp_next_handle = 1;
  59 static struct lock lhlock;
  60
  61 static int ncp_sysctl_connstat(SYSCTL_HANDLER_ARGS);
  62 static int ncp_conn_lock_any(struct ncp_conn *conn, struct thread *td,
  63     struct ucred *cred);
  64
  65 SYSCTL_DECL(_net_ncp);
  66 SYSCTL_INT (_net_ncp, OID_AUTO, burst_enabled, CTLFLAG_RD, &ncp_burst_enabled, 0, "");
  67 SYSCTL_INT (_net_ncp, OID_AUTO, conn_cnt, CTLFLAG_RD, &ncp_conn_cnt, 0, "");
  68 SYSCTL_PROC(_net_ncp, OID_AUTO, conn_stat, CTLFLAG_RD|CTLTYPE_OPAQUE,
  69             NULL, 0, ncp_sysctl_connstat, "S,connstat", "Connections list");
  70
  71 MALLOC_DEFINE(M_NCPDATA, "NCP data", "NCP private data");
  72
  73 int
  74 ncp_conn_init(void) {
  75         lockinit(&listlock, "ncpll", 0, 0);
  76         lockinit(&lhlock, "ncplh", 0, 0);
  77         return 0;
  78 }
  79
  80 int
  81 ncp_conn_locklist(int flags, struct thread *td)
  82 {
  83         return lockmgr(&listlock, flags | LK_CANRECURSE, NULL, td);
  84 }
  85
  86 void
  87 ncp_conn_unlocklist(struct thread *td)
  88 {
  89         lockmgr(&listlock, LK_RELEASE, NULL, td);
  90 }
  91
  92 int
  93 ncp_conn_access(struct ncp_conn *conn, struct ucred *cred, mode_t mode)
  94 {
  95         int error;
  96
  97         if (cred == NOCRED || ncp_suser(cred) == 0 ||
  98             cred->cr_uid == conn->nc_owner->cr_uid)
  99                 return 0;
 100         mode >>= 3;
 101         if (!groupmember(conn->nc_group, cred))
 102                 mode >>= 3;
 103         error = (conn->li.access_mode & mode) == mode ? 0 : EACCES;
 104         return error;
 105 }
 106
 107 int
 108 ncp_conn_lock_any(struct ncp_conn *conn, struct thread *td, struct ucred *cred)
 109 {
 110         int error;
 111
 112         if (conn->nc_id == 0) return EACCES;
 113         error = lockmgr(&conn->nc_lock, LK_EXCLUSIVE | LK_CANRECURSE, NULL, td);
 114         if (error == ERESTART)
 115                 return EINTR;
 116         error = ncp_chkintr(conn, td);
 117         if (error) {
 118                 lockmgr(&conn->nc_lock, LK_RELEASE, NULL, td);
 119                 return error;
 120         }
 121
 122         if (conn->nc_id == 0) {
 123                 lockmgr(&conn->nc_lock, LK_RELEASE, NULL, td);
 124                 return EACCES;
 125         }
 126         conn->td = td;  /* who currently operates */
 127         conn->ucred = cred;
 128         return 0;
 129 }
 130
 131 int
 132 ncp_conn_lock(struct ncp_conn *conn, struct thread *td,
 133         struct ucred *cred, int mode)
 134 {
 135         int error;
 136
 137         error = ncp_conn_access(conn, cred, mode);
 138         if (error)
 139                 return error;
 140         return ncp_conn_lock_any(conn, td, cred);
 141 }
 142
 143 /*
 144  * Lock conn but unlock connlist
 145  */
 146 static int
 147 ncp_conn_lock2(struct ncp_conn *conn, struct thread *td,
 148         struct ucred *cred, int mode)
 149 {
 150         int error;
 151
 152         error = ncp_conn_access(conn, cred, mode);
 153         if (error) {
 154                 ncp_conn_unlocklist(td);
 155                 return error;
 156         }
 157         conn->nc_lwant++;
 158         ncp_conn_unlocklist(td);
 159         error = ncp_conn_lock_any(conn, td, cred);
 160         conn->nc_lwant--;
 161         if (conn->nc_lwant == 0) {
 162                 wakeup(&conn->nc_lwant);
 163         }
 164         return error;
 165 }
 166
 167 void
 168 ncp_conn_unlock(struct ncp_conn *conn, struct thread *td) {
 169         /*
 170          * note, that LK_RELASE will do wakeup() instead of wakeup_one().
 171          * this will do a little overhead
 172          */
 173         lockmgr(&conn->nc_lock, LK_RELEASE, NULL, td);
 174 }
 175
 176 int
 177 ncp_conn_assert_locked(struct ncp_conn *conn, const char *checker,
 178                        struct thread *td)
 179 {
 180         if (conn->nc_lock.lk_flags & LK_HAVE_EXCL)
 181                 return 0;
 182         printf("%s: connection isn't locked!\n", checker);
 183         return EIO;
 184 }
 185
 186 /*
 187  * create, fill with defaults and return in locked state
 188  */
 189 int
 190 ncp_conn_alloc(struct thread *td, struct ucred *cred, struct ncp_conn **conn)
 191 {
 192         int error;
 193         struct ncp_conn *ncp;
 194
 195         MALLOC(ncp, struct ncp_conn *, sizeof(struct ncp_conn),
 196             M_NCPDATA, M_WAITOK | M_ZERO);
 197         error = 0;
 198         lockinit(&ncp->nc_lock, "ncplck", 0, 0);
 199         ncp_conn_cnt++;
 200         ncp->nc_id = ncp_next_ref++;
 201         ncp->nc_owner = cred;
 202         ncp->seq = 0;
 203         ncp->connid = 0xFFFF;
 204         ncp_conn_lock_any(ncp, td, ncp->nc_owner);
 205         *conn = ncp;
 206         ncp_conn_locklist(LK_EXCLUSIVE, td);
 207         SLIST_INSERT_HEAD(&conn_list,ncp,nc_next);
 208         ncp_conn_unlocklist(td);
 209         return (error);
 210 }
 211
 212 /*
 213  * Remove the connection, on entry it must be locked
 214  */
 215 int
 216 ncp_conn_free(struct ncp_conn *ncp)
 217 {
 218         int error;
 219         struct ncp_conn *ncp1;
 220
 221         if (ncp->nc_id == 0) {
 222                 printf("already!!!!\n");
 223                 return EACCES;
 224         }
 225         if (ncp==NULL) {
 226                 NCPFATAL("conn==NULL !\n");
 227                 return(EIO);
 228         }
 229         error = ncp_conn_assert_locked(ncp, __func__, ncp->td);
 230         if (error) return error;
 231         if (ncp->ref_cnt) {
 232                 NCPFATAL("there are %d referenses left\n",ncp->ref_cnt);
 233                 return(EBUSY);
 234         }
 235         /*
 236          * Mark conn as died and wait for other process
 237          */
 238         ncp->nc_id = 0;
 239         ncp_conn_unlock(ncp, ncp->td);
 240         /*
 241          * if signal is raised - how I do react ?
 242          */
 243         lockmgr(&ncp->nc_lock, LK_DRAIN, NULL, ncp->td);
 244         while (ncp->nc_lwant) {
 245                 printf("lwant = %d\n", ncp->nc_lwant);
 246                 tsleep(&ncp->nc_lwant, 0, "ncpdr", 2*hz);
 247         }
 248         ncp_conn_locklist(LK_EXCLUSIVE, ncp->td);
 249         /*
 250          * It is possible, that other process destroy connection while we draining,
 251          * and free it. So, we must rescan list
 252          */
 253         SLIST_FOREACH(ncp1, &conn_list, nc_next) {
 254                 if (ncp1 == ncp) break;
 255         }
 256         if (ncp1 == NULL) {
 257                 ncp_conn_unlocklist(ncp->td);
 258                 return 0;
 259         }
 260         SLIST_REMOVE(&conn_list, ncp, ncp_conn, nc_next);
 261         ncp_conn_cnt--;
 262         ncp_conn_unlocklist(ncp->td);
 263         if (ncp->li.user) free(ncp->li.user, M_NCPDATA);
 264         if (ncp->li.password) free(ncp->li.password, M_NCPDATA);
 265         crfree(ncp->nc_owner);
 266         FREE(ncp, M_NCPDATA);
 267         return (0);
 268 }
 269
 270 /*
 271  * Lookup connection by handle, return a locked conn descriptor
 272  */
 273 int
 274 ncp_conn_getbyref(int ref,struct thread *td,struct ucred *cred, int mode, struct ncp_conn **connpp){
 275         struct ncp_conn *ncp;
 276         int error=0;
 277
 278         ncp_conn_locklist(LK_SHARED, td);
 279         SLIST_FOREACH(ncp, &conn_list, nc_next)
 280                 if (ncp->nc_id == ref) break;
 281         if (ncp == NULL) {
 282                 ncp_conn_unlocklist(td);
 283                 return(EBADF);
 284         }
 285         error = ncp_conn_lock2(ncp, td, cred, mode);
 286         if (!error)
 287                 *connpp = ncp;
 288         return (error);
 289 }
 290 /*
 291  * find attached, but not logged in connection to specified server
 292  */
 293 int
 294 ncp_conn_getattached(struct ncp_conn_args *li,struct thread *td,struct ucred *cred,int mode, struct ncp_conn **connpp){
 295         struct ncp_conn *ncp, *ncp2=NULL;
 296         int error = 0;
 297
 298         ncp_conn_locklist(LK_SHARED, td);
 299         SLIST_FOREACH(ncp, &conn_list, nc_next) {
 300                 if ((ncp->flags & NCPFL_LOGGED) != 0 ||
 301                     strcmp(ncp->li.server,li->server) != 0 ||
 302                     ncp->li.saddr.sa_len != li->saddr.sa_len ||
 303                     bcmp(&ncp->li.saddr,&ncp->li.saddr,li->saddr.sa_len) != 0)
 304                         continue;
 305                 if (ncp_suser(cred) == 0 ||
 306                     cred->cr_uid == ncp->nc_owner->cr_uid)
 307                         break;
 308                 error = ncp_conn_access(ncp,cred,mode);
 309                 if (!error && ncp2 == NULL)
 310                         ncp2 = ncp;
 311         }
 312         if (ncp == NULL) ncp = ncp2;
 313         if (ncp == NULL) {
 314                 ncp_conn_unlocklist(td);
 315                 return(EBADF);
 316         }
 317         error = ncp_conn_lock2(ncp,td,cred,mode);
 318         if (!error)
 319                 *connpp=ncp;
 320         return (error);
 321 }
 322
 323 /*
 324  * Lookup connection by server/user pair, return a locked conn descriptor.
 325  * if li is NULL or server/user pair incomplete, try to select best connection
 326  * based on owner.
 327  * Connection selected in next order:
 328  * 1. Try to search conn with ucred owner, if li is NULL also find a primary
 329  * 2. If 1. fails try to get first suitable shared connection
 330  * 3. If 2. fails then nothing can help to poor ucred owner
 331  */
 332
 333 int
 334 ncp_conn_getbyli(struct ncp_conn_args *li, struct thread *td,
 335         struct ucred *cred, int mode, struct ncp_conn **connpp)
 336 {
 337         struct ncp_conn *ncp, *ncp2=NULL;
 338         int error=0, partial, haveserv;
 339
 340         partial = (li == NULL || li->server[0] == 0 || li->user == NULL);
 341         haveserv = (li && li->server[0]);
 342         ncp_conn_locklist(LK_SHARED, td);
 343         SLIST_FOREACH(ncp, &conn_list, nc_next) {
 344                 if (partial) {
 345                         if (cred->cr_uid == ncp->nc_owner->cr_uid) {
 346                                 if (haveserv) {
 347                                         if (strcmp(ncp->li.server,li->server) == 0)
 348                                                 break;
 349                                 } else {
 350                                         if (ncp->flags & NCPFL_PRIMARY)
 351                                                 break;
 352                                         ncp2 = ncp;
 353                                 }
 354                                 continue;
 355                         }
 356                 } else {
 357                         if (strcmp(ncp->li.server,li->server) != 0 ||
 358                             ncp->li.user == NULL ||
 359                             strcmp(ncp->li.user,li->user) != 0)
 360                                 continue;
 361                         if (cred->cr_uid == ncp->nc_owner->cr_uid)
 362                                 break;
 363                         if (ncp_suser(cred) == 0)
 364                                 ncp2 = ncp;
 365                 }
 366                 error = ncp_conn_access(ncp,cred,mode);
 367                 if (!error && ncp2 == NULL)
 368                         ncp2 = ncp;
 369         }
 370         if (ncp == NULL) ncp = ncp2;
 371         if (ncp == NULL) {
 372                 ncp_conn_unlocklist(td);
 373                 return(EBADF);
 374         }
 375         error = ncp_conn_lock2(ncp,td,cred,mode);
 376         if (!error)
 377                 *connpp=ncp;
 378         return (error);
 379 }
 380
 381 /*
 382  * Set primary connection flag, since it have sence only for an owner,
 383  * only owner can modify this flag.
 384  * connection expected to be locked.
 385  */
 386 int
 387 ncp_conn_setprimary(struct ncp_conn *conn, int on){
 388         struct ncp_conn *ncp=NULL;
 389
 390         if (conn->ucred->cr_uid != conn->nc_owner->cr_uid)
 391                 return EACCES;
 392         ncp_conn_locklist(LK_SHARED, conn->td);
 393         SLIST_FOREACH(ncp, &conn_list, nc_next) {
 394                 if (conn->ucred->cr_uid == ncp->nc_owner->cr_uid)
 395                         ncp->flags &= ~NCPFL_PRIMARY;
 396         }
 397         ncp_conn_unlocklist(conn->td);
 398         if (on)
 399                 conn->flags |= NCPFL_PRIMARY;
 400         return 0;
 401 }
 402 /*
 403  * Lease conn to given proc, returning unique handle
 404  * problem: how locks should be applied ?
 405  */
 406 int
 407 ncp_conn_gethandle(struct ncp_conn *conn, struct thread *td, struct ncp_handle **handle){
 408         struct ncp_handle *refp;
 409
 410         lockmgr(&lhlock, LK_EXCLUSIVE, NULL, td);
 411         SLIST_FOREACH(refp, &lhlist, nh_next)
 412                 if (refp->nh_conn == conn && td == refp->nh_td) break;
 413         if (refp) {
 414                 conn->ref_cnt++;
 415                 refp->nh_ref++;
 416                 *handle = refp;
 417                 lockmgr(&lhlock, LK_RELEASE, NULL, td);
 418                 return 0;
 419         }
 420         MALLOC(refp,struct ncp_handle *,sizeof(struct ncp_handle),M_NCPDATA,
 421             M_WAITOK | M_ZERO);
 422         SLIST_INSERT_HEAD(&lhlist,refp,nh_next);
 423         refp->nh_ref++;
 424         refp->nh_td = td;
 425         refp->nh_conn = conn;
 426         refp->nh_id = ncp_next_handle++;
 427         *handle = refp;
 428         conn->ref_cnt++;
 429         lockmgr(&lhlock, LK_RELEASE, NULL, td);
 430         return 0;
 431 }
 432 /*
 433  * release reference, if force - ignore refcount
 434  */
 435 int
 436 ncp_conn_puthandle(struct ncp_handle *handle, struct thread *td, int force) {
 437         struct ncp_handle *refp = handle;
 438
 439         lockmgr(&lhlock, LK_EXCLUSIVE, NULL, td);
 440         refp->nh_ref--;
 441         refp->nh_conn->ref_cnt--;
 442         if (force) {
 443                 refp->nh_conn->ref_cnt -= refp->nh_ref;
 444                 refp->nh_ref = 0;
 445         }
 446         if (refp->nh_ref == 0) {
 447                 SLIST_REMOVE(&lhlist, refp, ncp_handle, nh_next);
 448                 FREE(refp, M_NCPDATA);
 449         }
 450         lockmgr(&lhlock, LK_RELEASE, NULL, td);
 451         return 0;
 452 }
 453 /*
 454  * find a connHandle
 455  */
 456 int
 457 ncp_conn_findhandle(int connHandle, struct thread *td, struct ncp_handle **handle) {
 458         struct ncp_handle *refp;
 459
 460         lockmgr(&lhlock, LK_SHARED, NULL, td);
 461         SLIST_FOREACH(refp, &lhlist, nh_next)
 462                 if (refp->nh_td == td && refp->nh_id == connHandle) break;
 463         lockmgr(&lhlock, LK_RELEASE, NULL, td);
 464         if (refp == NULL) {
 465                 return EBADF;
 466         }
 467         *handle = refp;
 468         return 0;
 469 }
 470 /*
 471  * Clear handles associated with specified process
 472  */
 473 int
 474 ncp_conn_putprochandles(struct thread *td) {
 475         struct ncp_handle *hp, *nhp;
 476         int haveone = 0;
 477
 478         lockmgr(&lhlock, LK_EXCLUSIVE, NULL, td);
 479         for (hp = SLIST_FIRST(&lhlist); hp; hp = nhp) {
 480                 nhp = SLIST_NEXT(hp, nh_next);
 481                 if (hp->nh_td != td) continue;
 482                 haveone = 1;
 483                 hp->nh_conn->ref_cnt -= hp->nh_ref;
 484                 SLIST_REMOVE(&lhlist, hp, ncp_handle, nh_next);
 485                 FREE(hp, M_NCPDATA);
 486         }
 487         lockmgr(&lhlock, LK_RELEASE, NULL, td);
 488         return haveone;
 489 }
 490 /*
 491  * remove references in all possible connections,
 492  * XXX - possible problem is a locked list.
 493  */
 494 /*void
 495 ncp_conn_list_rm_ref(pid_t pid) {
 496         struct ncp_conn *ncp;
 497
 498         ncp_conn_locklist(LK_SHARED, NULL);
 499         SLIST_FOREACH(ncp, &conn_list, nc_next) {
 500                 ncp_conn_rm_ref(ncp,pid,1);
 501         }
 502         ncp_conn_unlocklist(NULL);
 503         return;
 504 }
 505 */
 506 int
 507 ncp_conn_getinfo(struct ncp_conn *ncp, struct ncp_conn_stat *ncs) {
 508         bzero(ncs,sizeof(*ncs));
 509         ncs->li = ncp->li;
 510         ncs->li.user = ncs->user;
 511         if (ncp->li.user)
 512                 strcpy(ncs->user, ncp->li.user);
 513         ncs->li.password = NULL;
 514         ncs->connRef = ncp->nc_id;
 515         ncs->ref_cnt = ncp->ref_cnt;
 516         ncs->connid = ncp->connid;
 517         ncs->owner = ncp->nc_owner->cr_uid;
 518         ncs->group = ncp->nc_group;
 519         ncs->flags = ncp->flags;
 520         ncs->buffer_size = ncp->buffer_size;
 521         return 0;
 522 }
 523
 524 static int
 525 ncp_sysctl_connstat(SYSCTL_HANDLER_ARGS) {
 526         int error;
 527         struct ncp_conn_stat ncs;
 528         struct ncp_conn *ncp;
 529 /*      struct ucred *cred = req->p->p_ucred;*/
 530
 531         error = 0;
 532         ncp_conn_locklist(LK_SHARED, req->td);
 533         error = SYSCTL_OUT(req, &ncp_conn_cnt, sizeof(ncp_conn_cnt));
 534         SLIST_FOREACH(ncp, &conn_list, nc_next) {
 535                 if (error) break;
 536                 /* I can't do conn_lock while list is locked */
 537                 ncp->nc_lwant++;
 538                 if (!error) {
 539                         ncp_conn_getinfo(ncp, &ncs);
 540                 } else {
 541                         bzero(&ncs,sizeof(ncs));
 542                         ncs.connRef = ncp->nc_id;
 543                         strcpy(ncs.li.server,"***");
 544                 }
 545                 ncp->nc_lwant--;
 546                 error = SYSCTL_OUT(req, &ncs, sizeof(ncs));
 547         }
 548         ncp_conn_unlocklist(req->td);
 549         return(error);
 550 }