/*- * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Berkeley Software Design Inc's name may not be used to endorse or * promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from BSDI kern.c,v 1.2 1998/11/25 22:38:27 don Exp * $FreeBSD: src/usr.sbin/rpc.lockd/kern.c,v 1.11 2002/08/15 21:52:21 alfred Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "rpcsvc/nlm_prot.h" #include #include #include #include #include "lockd.h" #include "lockd_lock.h" #define DAEMON_USERNAME "daemon" #define nfslockdans(_v, _ansp) \ ((_ansp)->la_vers = (_v), \ nfsclnt(NFSCLNT_LOCKDANS, (_ansp))) /* Lock request owner. */ typedef struct __owner { pid_t pid; /* Process ID. */ time_t tod; /* Time-of-day. */ } OWNER; static OWNER owner; static char hostname[MAXHOSTNAMELEN + 1]; /* Hostname. */ static void client_cleanup(void); static void set_auth(CLIENT *cl, struct xucred *ucred); int lock_request(LOCKD_MSG *); int test_request(LOCKD_MSG *); void show(LOCKD_MSG *); int unlock_request(LOCKD_MSG *); /* * will break because fifo needs to be repopened when EOF'd */ #define lockd_seteuid(uid) seteuid(uid) #define d_calls (debug_level > 1) #define d_args (debug_level > 2) static const char * from_addr(saddr) struct sockaddr *saddr; { static char inet_buf[INET6_ADDRSTRLEN]; if (getnameinfo(saddr, saddr->sa_len, inet_buf, sizeof(inet_buf), NULL, 0, NI_NUMERICHOST) == 0) return inet_buf; return "???"; } /* * client_kern_wait() * * wait for kernel to signal first lock request before starting */ void client_kern_wait(void) { if (nfsclnt(NFSCLNT_LOCKDWAIT, NULL)) warn("nfsclnt_lockdwait"); } void client_cleanup(void) { (void)lockd_seteuid(0); (void) nfsclnt(NFSCLNT_LOCKDFD, (struct lockd_ans *)-1); exit(-1); } /* * client_request -- * Loop around messages from the kernel, forwarding them off to * NLM servers. */ pid_t client_request(void) { LOCKD_MSG msg; /* * select on FIFOs can currently hang, so we'll use * the nfslockdwait syscall instead for now. */ #define USE_NFSLOCKDWAIT_INSTEAD_OF_SELECT 1 #ifndef USE_NFSLOCKDWAIT_INSTEAD_OF_SELECT fd_set rdset; #endif int fd, nr, ret; pid_t child; uid_t daemon_uid; mode_t old_umask; struct passwd *pw; /* Recreate the NLM fifo. */ (void)unlink(_PATH_LCKFIFO); old_umask = umask(S_IXGRP|S_IXOTH); if (mkfifo(_PATH_LCKFIFO, S_IWUSR | S_IRUSR)) { syslog(LOG_ERR, "mkfifo: %s: %m", _PATH_LCKFIFO); exit (1); } umask(old_umask); /* * Create a separate process, the client code is really a separate * daemon that shares a lot of code. */ switch (child = fork()) { case -1: err(1, "fork"); case 0: break; default: return (child); } signal(SIGHUP, (sig_t)client_cleanup); signal(SIGTERM, (sig_t)client_cleanup); /* Setup. */ (void)time(&owner.tod); owner.pid = getpid(); (void)gethostname(hostname, sizeof(hostname) - 1); /* Open the fifo for reading. */ if ((fd = open(_PATH_LCKFIFO, O_RDONLY | O_NONBLOCK)) == -1) { syslog(LOG_ERR, "open: %s: %m", _PATH_LCKFIFO); goto err; } (void)unlink(_PATH_LCKFIFO); if (nfsclnt(NFSCLNT_LOCKDFD, (struct lockd_ans *)fd)) { syslog(LOG_ERR, "nfsclnt_fd: %d: %m", fd); goto err; } pw = getpwnam(DAEMON_USERNAME); if (pw == NULL) { syslog(LOG_ERR, "getpwnam: %s: %m", DAEMON_USERNAME); goto err; } daemon_uid = pw->pw_uid; /* drop our root priviledges */ (void)lockd_seteuid(daemon_uid); for (;;) { #ifndef USE_NFSLOCKDWAIT_INSTEAD_OF_SELECT /* Wait for contact... fifo's return EAGAIN when read with * no data */ /* Set up the select. */ FD_ZERO(&rdset); FD_SET(fd, &rdset); (void)select(fd + 1, &rdset, NULL, NULL, NULL); #endif /* Read the fixed length message. */ if ((nr = read(fd, &msg, sizeof(msg))) == sizeof(msg)) { if (d_args) show(&msg); if (msg.lm_version != LOCKD_MSG_VERSION) { syslog(LOG_ERR, "unknown msg type: %d", msg.lm_version); } /* * Send it to the NLM server and don't grant the lock * if we fail for any reason. */ switch (msg.lm_fl.l_type) { case F_RDLCK: case F_WRLCK: if (msg.lm_getlk) ret = test_request(&msg); else ret = lock_request(&msg); break; case F_UNLCK: ret = unlock_request(&msg); break; default: ret = 1; syslog(LOG_ERR, "unknown lock type: %d", msg.lm_fl.l_type); break; } if (ret) { struct lockd_ans ans; ans.la_msg_ident = msg.lm_msg_ident; ans.la_errno = ENOTSUP; if (nfslockdans(LOCKD_ANS_VERSION, &ans)) { syslog(LOG_DEBUG, "process %lu: %m", (u_long)msg.lm_msg_ident.pid); } } } else if (nr == -1) { if (errno != EAGAIN) { syslog(LOG_ERR, "read: %s: %m", _PATH_LCKFIFO); goto err; } #ifdef USE_NFSLOCKDWAIT_INSTEAD_OF_SELECT else nfsclnt(NFSCLNT_LOCKDWAIT, NULL); #endif } else if (nr != 0) { syslog(LOG_ERR, "%s: discard %d bytes", _PATH_LCKFIFO, nr); } #ifdef USE_NFSLOCKDWAIT_INSTEAD_OF_SELECT else nfsclnt(NFSCLNT_LOCKDWAIT, NULL); #endif } /* Reached only on error. */ err: (void)lockd_seteuid(0); (void) nfsclnt(NFSCLNT_LOCKDFD, (struct lockd_ans *)-1); _exit (1); return 0; } void set_auth(cl, xucred) CLIENT *cl; struct xucred *xucred; { if (cl->cl_auth != NULL) cl->cl_auth->ah_ops->ah_destroy(cl->cl_auth); cl->cl_auth = authunix_create(hostname, xucred->cr_uid, xucred->cr_groups[0], xucred->cr_ngroups - 1, &xucred->cr_groups[1]); } /* * test_request -- * Convert a lock LOCKD_MSG into an NLM request, and send it off. */ int test_request(LOCKD_MSG *msg) { CLIENT *cli; struct timeval timeout = {0, 0}; /* No timeout, no response. */ char dummy; if (d_calls) syslog(LOG_DEBUG, "test request: %s: %s to %s", msg->lm_nfsv3 ? "V4" : "V1/3", msg->lm_fl.l_type == F_WRLCK ? "write" : "read", from_addr((struct sockaddr *)&msg->lm_addr)); if (msg->lm_nfsv3) { struct nlm4_testargs arg4; arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg4.cookie.n_len = sizeof(msg->lm_msg_ident); arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; arg4.alock.caller_name = hostname; arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; arg4.alock.fh.n_len = msg->lm_fh_len; arg4.alock.oh.n_bytes = (char *)&owner; arg4.alock.oh.n_len = sizeof(owner); arg4.alock.svid = msg->lm_msg_ident.pid; arg4.alock.l_offset = msg->lm_fl.l_start; arg4.alock.l_len = msg->lm_fl.l_len; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS4)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_TEST_MSG, xdr_nlm4_testargs, &arg4, xdr_void, &dummy, timeout); } else { struct nlm_testargs arg; arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg.cookie.n_len = sizeof(msg->lm_msg_ident); arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; arg.alock.caller_name = hostname; arg.alock.fh.n_bytes = (char *)&msg->lm_fh; arg.alock.fh.n_len = msg->lm_fh_len; arg.alock.oh.n_bytes = (char *)&owner; arg.alock.oh.n_len = sizeof(owner); arg.alock.svid = msg->lm_msg_ident.pid; arg.alock.l_offset = msg->lm_fl.l_start; arg.alock.l_len = msg->lm_fl.l_len; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_TEST_MSG, xdr_nlm_testargs, &arg, xdr_void, &dummy, timeout); } return (0); } /* * lock_request -- * Convert a lock LOCKD_MSG into an NLM request, and send it off. */ int lock_request(LOCKD_MSG *msg) { CLIENT *cli; struct nlm4_lockargs arg4; struct nlm_lockargs arg; struct timeval timeout = {0, 0}; /* No timeout, no response. */ char dummy; if (d_calls) syslog(LOG_DEBUG, "lock request: %s: %s to %s", msg->lm_nfsv3 ? "V4" : "V1/3", msg->lm_fl.l_type == F_WRLCK ? "write" : "read", from_addr((struct sockaddr *)&msg->lm_addr)); if (msg->lm_nfsv3) { arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg4.cookie.n_len = sizeof(msg->lm_msg_ident); arg4.block = msg->lm_wait ? 1 : 0; arg4.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; arg4.alock.caller_name = hostname; arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; arg4.alock.fh.n_len = msg->lm_fh_len; arg4.alock.oh.n_bytes = (char *)&owner; arg4.alock.oh.n_len = sizeof(owner); arg4.alock.svid = msg->lm_msg_ident.pid; arg4.alock.l_offset = msg->lm_fl.l_start; arg4.alock.l_len = msg->lm_fl.l_len; arg4.reclaim = 0; arg4.state = nsm_state; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS4)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_LOCK_MSG, xdr_nlm4_lockargs, &arg4, xdr_void, &dummy, timeout); } else { arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg.cookie.n_len = sizeof(msg->lm_msg_ident); arg.block = msg->lm_wait ? 1 : 0; arg.exclusive = msg->lm_fl.l_type == F_WRLCK ? 1 : 0; arg.alock.caller_name = hostname; arg.alock.fh.n_bytes = (char *)&msg->lm_fh; arg.alock.fh.n_len = msg->lm_fh_len; arg.alock.oh.n_bytes = (char *)&owner; arg.alock.oh.n_len = sizeof(owner); arg.alock.svid = msg->lm_msg_ident.pid; arg.alock.l_offset = msg->lm_fl.l_start; arg.alock.l_len = msg->lm_fl.l_len; arg.reclaim = 0; arg.state = nsm_state; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_LOCK_MSG, xdr_nlm_lockargs, &arg, xdr_void, &dummy, timeout); } return (0); } /* * unlock_request -- * Convert an unlock LOCKD_MSG into an NLM request, and send it off. */ int unlock_request(LOCKD_MSG *msg) { CLIENT *cli; struct nlm4_unlockargs arg4; struct nlm_unlockargs arg; struct timeval timeout = {0, 0}; /* No timeout, no response. */ char dummy; if (d_calls) syslog(LOG_DEBUG, "unlock request: %s: to %s", msg->lm_nfsv3 ? "V4" : "V1/3", from_addr((struct sockaddr *)&msg->lm_addr)); if (msg->lm_nfsv3) { arg4.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg4.cookie.n_len = sizeof(msg->lm_msg_ident); arg4.alock.caller_name = hostname; arg4.alock.fh.n_bytes = (char *)&msg->lm_fh; arg4.alock.fh.n_len = msg->lm_fh_len; arg4.alock.oh.n_bytes = (char *)&owner; arg4.alock.oh.n_len = sizeof(owner); arg4.alock.svid = msg->lm_msg_ident.pid; arg4.alock.l_offset = msg->lm_fl.l_start; arg4.alock.l_len = msg->lm_fl.l_len; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS4)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_UNLOCK_MSG, xdr_nlm4_unlockargs, &arg4, xdr_void, &dummy, timeout); } else { arg.cookie.n_bytes = (char *)&msg->lm_msg_ident; arg.cookie.n_len = sizeof(msg->lm_msg_ident); arg.alock.caller_name = hostname; arg.alock.fh.n_bytes = (char *)&msg->lm_fh; arg.alock.fh.n_len = msg->lm_fh_len; arg.alock.oh.n_bytes = (char *)&owner; arg.alock.oh.n_len = sizeof(owner); arg.alock.svid = msg->lm_msg_ident.pid; arg.alock.l_offset = msg->lm_fl.l_start; arg.alock.l_len = msg->lm_fl.l_len; if ((cli = get_client( (struct sockaddr *)&msg->lm_addr, NLM_VERS)) == NULL) return (1); set_auth(cli, &msg->lm_cred); (void)clnt_call(cli, NLM_UNLOCK_MSG, xdr_nlm_unlockargs, &arg, xdr_void, &dummy, timeout); } return (0); } int lock_answer(int pid, netobj *netcookie, int result, int version, int *pid_p, off_t l_start, off_t l_len) { struct lockd_ans ans; if (netcookie->n_len != sizeof(ans.la_msg_ident)) { if (pid == -1) { /* we're screwed */ syslog(LOG_ERR, "inedible nlm cookie"); return -1; } ans.la_msg_ident.pid = pid; ans.la_msg_ident.msg_seq = -1; } else { memcpy(&ans.la_msg_ident, netcookie->n_bytes, sizeof(ans.la_msg_ident)); } if (d_calls) syslog(LOG_DEBUG, "lock answer: pid %lu: %s %d", (unsigned long)ans.la_msg_ident.pid, version == NLM_VERS4 ? "nlmv4" : "nlmv3", result); ans.la_getlk_set = 0; if (version == NLM_VERS4) switch (result) { case nlm4_granted: ans.la_errno = 0; break; default: ans.la_errno = EACCES; break; case nlm4_denied: if (pid_p == NULL) ans.la_errno = EACCES; else { /* this is an answer to a nlm_test msg */ ans.la_getlk_set = 1; ans.la_getlk_pid = *pid_p; ans.la_getlk_start = l_start; ans.la_getlk_len = l_len; ans.la_errno = 0; } break; case nlm4_denied_nolocks: ans.la_errno = ENOLCK; break; case nlm4_blocked: return -1; /* NOTREACHED */ case nlm4_denied_grace_period: ans.la_errno = EAGAIN; break; case nlm4_deadlck: ans.la_errno = EDEADLK; break; case nlm4_rofs: ans.la_errno = EROFS; break; case nlm4_stale_fh: ans.la_errno = ESTALE; break; case nlm4_fbig: ans.la_errno = EFBIG; break; case nlm4_failed: ans.la_errno = EACCES; break; } else switch (result) { case nlm_granted: ans.la_errno = 0; break; default: ans.la_errno = EACCES; break; case nlm_denied: if (pid_p == NULL) ans.la_errno = EACCES; else { /* this is an answer to a nlm_test msg */ ans.la_getlk_set = 1; ans.la_getlk_pid = *pid_p; ans.la_getlk_start = l_start; ans.la_getlk_len = l_len; ans.la_errno = 0; } break; case nlm_denied_nolocks: ans.la_errno = ENOLCK; break; case nlm_blocked: return -1; /* NOTREACHED */ case nlm_denied_grace_period: ans.la_errno = EAGAIN; break; case nlm_deadlck: ans.la_errno = EDEADLK; break; } if (nfslockdans(LOCKD_ANS_VERSION, &ans)) { syslog(LOG_DEBUG, "lock_answer(%d): process %lu: %m", result, (u_long)ans.la_msg_ident.pid); return -1; } return 0; } /* * show -- * Display the contents of a kernel LOCKD_MSG structure. */ void show(LOCKD_MSG *mp) { static char hex[] = "0123456789abcdef"; struct fid *fidp; fsid_t *fsidp; size_t len; u_int8_t *p, *t, buf[NFS_SMALLFH*3+1]; syslog(LOG_DEBUG, "process ID: %lu\n", (long)mp->lm_msg_ident.pid); fsidp = (fsid_t *)&mp->lm_fh; fidp = (struct fid *)((u_int8_t *)&mp->lm_fh + sizeof(fsid_t)); for (t = buf, p = (u_int8_t *)mp->lm_fh, len = mp->lm_fh_len; len > 0; ++p, --len) { *t++ = '\\'; *t++ = hex[(*p & 0xf0) >> 4]; *t++ = hex[*p & 0x0f]; } *t = '\0'; syslog(LOG_DEBUG, "fh_len %d, fh %s\n", mp->lm_fh_len, buf); /* Show flock structure. */ syslog(LOG_DEBUG, "start %qu; len %qu; pid %lu; type %d; whence %d\n", mp->lm_fl.l_start, mp->lm_fl.l_len, (u_long)mp->lm_fl.l_pid, mp->lm_fl.l_type, mp->lm_fl.l_whence); /* Show wait flag. */ syslog(LOG_DEBUG, "wait was %s\n", mp->lm_wait ? "set" : "not set"); }