/*- * Copyright (c) 2011 James Gritton * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "jailp.h" #define DEFAULT_STOP_TIMEOUT 10 #define PHASH_SIZE 256 LIST_HEAD(phhead, phash); struct phash { LIST_ENTRY(phash) le; struct cfjail *j; pid_t pid; }; int paralimit = -1; extern char **environ; static int run_command(struct cfjail *j); static int add_proc(struct cfjail *j, pid_t pid); static void clear_procs(struct cfjail *j); static struct cfjail *find_proc(pid_t pid); static int term_procs(struct cfjail *j); static int get_user_info(struct cfjail *j, const char *username, const struct passwd **pwdp, login_cap_t **lcapp); static int check_path(struct cfjail *j, const char *pname, const char *path, int isfile, const char *umount_type); static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping); static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable); static struct cfstring dummystring = { .len = 1 }; static struct phhead phash[PHASH_SIZE]; static int kq; /* * Run the next command associated with a jail. */ int next_command(struct cfjail *j) { enum intparam comparam; int create_failed, stopping; if (paralimit == 0) { requeue(j, &runnable); return 1; } create_failed = (j->flags & (JF_STOP | JF_FAILED)) == JF_FAILED; stopping = (j->flags & JF_STOP) != 0; comparam = *j->comparam; for (;;) { if (j->comstring == NULL) { j->comparam += create_failed ? -1 : 1; switch ((comparam = *j->comparam)) { case IP__NULL: return 0; case IP_MOUNT_DEVFS: if (!bool_param(j->intparams[IP_MOUNT_DEVFS])) continue; /* FALLTHROUGH */ case IP__OP: case IP_STOP_TIMEOUT: j->comstring = &dummystring; break; default: if (j->intparams[comparam] == NULL) continue; j->comstring = create_failed || (stopping && (j->intparams[comparam]->flags & PF_REV)) ? TAILQ_LAST(&j->intparams[comparam]->val, cfstrings) : TAILQ_FIRST(&j->intparams[comparam]->val); } } else { j->comstring = j->comstring == &dummystring ? NULL : create_failed || (stopping && (j->intparams[comparam]->flags & PF_REV)) ? TAILQ_PREV(j->comstring, cfstrings, tq) : TAILQ_NEXT(j->comstring, tq); } if (j->comstring == NULL || j->comstring->len == 0 || (create_failed && (comparam == IP_EXEC_PRESTART || comparam == IP_EXEC_START || comparam == IP_COMMAND || comparam == IP_EXEC_POSTSTART))) continue; switch (run_command(j)) { case -1: failed(j); /* FALLTHROUGH */ case 1: return 1; } } } /* * Check command exit status */ int finish_command(struct cfjail *j) { int error; if (!(j->flags & JF_SLEEPQ)) return 0; j->flags &= ~JF_SLEEPQ; if (*j->comparam == IP_STOP_TIMEOUT) { j->flags &= ~JF_TIMEOUT; j->pstatus = 0; return 0; } paralimit++; if (!TAILQ_EMPTY(&runnable)) requeue(TAILQ_FIRST(&runnable), &ready); error = 0; if (j->flags & JF_TIMEOUT) { j->flags &= ~JF_TIMEOUT; if (*j->comparam != IP_STOP_TIMEOUT) { jail_warnx(j, "%s: timed out", j->comline); failed(j); error = -1; } else if (verbose > 0) jail_note(j, "timed out\n"); } else if (j->pstatus != 0) { if (WIFSIGNALED(j->pstatus)) jail_warnx(j, "%s: exited on signal %d", j->comline, WTERMSIG(j->pstatus)); else jail_warnx(j, "%s: failed", j->comline); j->pstatus = 0; failed(j); error = -1; } free(j->comline); j->comline = NULL; return error; } /* * Check for finished processes or timeouts. */ struct cfjail * next_proc(int nonblock) { struct kevent ke; struct timespec ts; struct timespec *tsp; struct cfjail *j; if (!TAILQ_EMPTY(&sleeping)) { again: tsp = NULL; if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) { clock_gettime(CLOCK_REALTIME, &ts); ts.tv_sec = j->timeout.tv_sec - ts.tv_sec; ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec; if (ts.tv_nsec < 0) { ts.tv_sec--; ts.tv_nsec += 1000000000; } if (ts.tv_sec < 0 || (ts.tv_sec == 0 && ts.tv_nsec == 0)) { j->flags |= JF_TIMEOUT; clear_procs(j); return j; } tsp = &ts; } if (nonblock) { ts.tv_sec = 0; ts.tv_nsec = 0; tsp = &ts; } switch (kevent(kq, NULL, 0, &ke, 1, tsp)) { case -1: if (errno != EINTR) err(1, "kevent"); goto again; case 0: if (!nonblock) { j = TAILQ_FIRST(&sleeping); j->flags |= JF_TIMEOUT; clear_procs(j); return j; } break; case 1: (void)waitpid(ke.ident, NULL, WNOHANG); if ((j = find_proc(ke.ident))) { j->pstatus = ke.data; return j; } goto again; } } return NULL; } /* * Run a single command for a jail, possible inside the jail. */ static int run_command(struct cfjail *j) { const struct passwd *pwd; const struct cfstring *comstring, *s; login_cap_t *lcap; char **argv; char *cs, *comcs, *devpath; const char *jidstr, *conslog, *path, *ruleset, *term, *username; enum intparam comparam; size_t comlen; pid_t pid; int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout; #if defined(INET) || defined(INET6) char *addr; #endif static char *cleanenv; /* Perform some operations that aren't actually commands */ comparam = *j->comparam; down = j->flags & (JF_STOP | JF_FAILED); switch (comparam) { case IP_STOP_TIMEOUT: return term_procs(j); case IP__OP: if (down) { if (jail_remove(j->jid) < 0 && errno == EPERM) { jail_warnx(j, "jail_remove: %s", strerror(errno)); return -1; } if (verbose > 0 || (verbose == 0 && (j->flags & JF_STOP ? note_remove : j->name != NULL))) jail_note(j, "removed\n"); j->jid = -1; if (j->flags & JF_STOP) dep_done(j, DF_LIGHT); else j->flags &= ~JF_PERSIST; } else { if (create_jail(j) < 0) return -1; if (iflag) printf("%d\n", j->jid); if (verbose >= 0 && (j->name || verbose > 0)) jail_note(j, "created\n"); dep_done(j, DF_LIGHT); } return 0; default: ; } /* * Collect exec arguments. Internal commands for network and * mounting build their own argument lists. */ comstring = j->comstring; bg = 0; switch (comparam) { #ifdef INET case IP__IP4_IFADDR: argv = alloca(8 * sizeof(char *)); *(const char **)&argv[0] = _PATH_IFCONFIG; if ((cs = strchr(comstring->s, '|'))) { argv[1] = alloca(cs - comstring->s + 1); strlcpy(argv[1], comstring->s, cs - comstring->s + 1); addr = cs + 1; } else { *(const char **)&argv[1] = string_param(j->intparams[IP_INTERFACE]); addr = comstring->s; } *(const char **)&argv[2] = "inet"; if (!(cs = strchr(addr, '/'))) { argv[3] = addr; *(const char **)&argv[4] = "netmask"; *(const char **)&argv[5] = "255.255.255.255"; argc = 6; } else if (strchr(cs + 1, '.')) { argv[3] = alloca(cs - addr + 1); strlcpy(argv[3], addr, cs - addr + 1); *(const char **)&argv[4] = "netmask"; *(const char **)&argv[5] = cs + 1; argc = 6; } else { argv[3] = addr; argc = 4; } *(const char **)&argv[argc] = down ? "-alias" : "alias"; argv[argc + 1] = NULL; break; #endif #ifdef INET6 case IP__IP6_IFADDR: argv = alloca(8 * sizeof(char *)); *(const char **)&argv[0] = _PATH_IFCONFIG; if ((cs = strchr(comstring->s, '|'))) { argv[1] = alloca(cs - comstring->s + 1); strlcpy(argv[1], comstring->s, cs - comstring->s + 1); addr = cs + 1; } else { *(const char **)&argv[1] = string_param(j->intparams[IP_INTERFACE]); addr = comstring->s; } *(const char **)&argv[2] = "inet6"; argv[3] = addr; if (!(cs = strchr(addr, '/'))) { *(const char **)&argv[4] = "prefixlen"; *(const char **)&argv[5] = "128"; argc = 6; } else argc = 4; *(const char **)&argv[argc] = down ? "-alias" : "alias"; argv[argc + 1] = NULL; break; #endif case IP_VNET_INTERFACE: argv = alloca(5 * sizeof(char *)); *(const char **)&argv[0] = _PATH_IFCONFIG; argv[1] = comstring->s; *(const char **)&argv[2] = down ? "-vnet" : "vnet"; jidstr = string_param(j->intparams[KP_JID]); *(const char **)&argv[3] = jidstr ? jidstr : string_param(j->intparams[KP_NAME]); argv[4] = NULL; break; case IP_MOUNT: case IP__MOUNT_FROM_FSTAB: argv = alloca(8 * sizeof(char *)); comcs = alloca(comstring->len + 1); strcpy(comcs, comstring->s); argc = 0; for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4; cs = strtok(NULL, " \t\f\v\r\n")) argv[argc++] = cs; if (argc == 0) return 0; if (argc < 3) { jail_warnx(j, "%s: %s: missing information", j->intparams[comparam]->name, comstring->s); return -1; } if (check_path(j, j->intparams[comparam]->name, argv[1], 0, down ? argv[2] : NULL) < 0) return -1; if (down) { argv[4] = NULL; argv[3] = argv[1]; *(const char **)&argv[0] = "/sbin/umount"; } else { if (argc == 4) { argv[7] = NULL; argv[6] = argv[1]; argv[5] = argv[0]; argv[4] = argv[3]; *(const char **)&argv[3] = "-o"; } else { argv[5] = NULL; argv[4] = argv[1]; argv[3] = argv[0]; } *(const char **)&argv[0] = _PATH_MOUNT; } *(const char **)&argv[1] = "-t"; break; case IP_MOUNT_DEVFS: argv = alloca(7 * sizeof(char *)); path = string_param(j->intparams[KP_PATH]); if (path == NULL) { jail_warnx(j, "mount.devfs: no path"); return -1; } devpath = alloca(strlen(path) + 5); sprintf(devpath, "%s/dev", path); if (check_path(j, "mount.devfs", devpath, 0, down ? "devfs" : NULL) < 0) return -1; if (down) { *(const char **)&argv[0] = "/sbin/umount"; argv[1] = devpath; argv[2] = NULL; } else { *(const char **)&argv[0] = _PATH_MOUNT; *(const char **)&argv[1] = "-t"; *(const char **)&argv[2] = "devfs"; ruleset = string_param(j->intparams[KP_DEVFS_RULESET]); if (!ruleset) ruleset = "4"; /* devfsrules_jail */ argv[3] = alloca(11 + strlen(ruleset)); sprintf(argv[3], "-oruleset=%s", ruleset); *(const char **)&argv[4] = "."; argv[5] = devpath; argv[6] = NULL; } break; case IP_COMMAND: if (j->name != NULL) goto default_command; argc = 0; TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq) argc++; argv = alloca((argc + 1) * sizeof(char *)); argc = 0; TAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq) argv[argc++] = s->s; argv[argc] = NULL; j->comstring = &dummystring; break; default: default_command: if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) && !(cs[0] == '&' && cs[1] == '\0')) { argv = alloca(4 * sizeof(char *)); *(const char **)&argv[0] = _PATH_BSHELL; *(const char **)&argv[1] = "-c"; argv[2] = comstring->s; argv[3] = NULL; } else { if (cs) { *cs = 0; bg = 1; } comcs = alloca(comstring->len + 1); strcpy(comcs, comstring->s); argc = 0; for (cs = strtok(comcs, " \t\f\v\r\n"); cs; cs = strtok(NULL, " \t\f\v\r\n")) argc++; argv = alloca((argc + 1) * sizeof(char *)); strcpy(comcs, comstring->s); argc = 0; for (cs = strtok(comcs, " \t\f\v\r\n"); cs; cs = strtok(NULL, " \t\f\v\r\n")) argv[argc++] = cs; argv[argc] = NULL; } } if (argv[0] == NULL) return 0; if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) && timeout != 0) { clock_gettime(CLOCK_REALTIME, &j->timeout); j->timeout.tv_sec += timeout; } else j->timeout.tv_sec = 0; injail = comparam == IP_EXEC_START || comparam == IP_COMMAND || comparam == IP_EXEC_STOP; clean = bool_param(j->intparams[IP_EXEC_CLEAN]); username = string_param(j->intparams[injail ? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]); sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]); consfd = 0; if (injail && (conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) { if (check_path(j, "exec.consolelog", conslog, 1, NULL) < 0) return -1; consfd = open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE); if (consfd < 0) { jail_warnx(j, "open %s: %s", conslog, strerror(errno)); return -1; } } comlen = 0; for (i = 0; argv[i]; i++) comlen += strlen(argv[i]) + 1; j->comline = cs = emalloc(comlen); for (i = 0; argv[i]; i++) { strcpy(cs, argv[i]); if (argv[i + 1]) { cs += strlen(argv[i]) + 1; cs[-1] = ' '; } } if (verbose > 0) jail_note(j, "run command%s%s%s: %s\n", injail ? " in jail" : "", username ? " as " : "", username ? username : "", j->comline); pid = fork(); if (pid < 0) err(1, "fork"); if (pid > 0) { if (bg || !add_proc(j, pid)) { free(j->comline); j->comline = NULL; return 0; } else { paralimit--; return 1; } } if (bg) setsid(); /* Set up the environment and run the command */ pwd = NULL; lcap = NULL; if ((clean || username) && injail && sjuser && get_user_info(j, username, &pwd, &lcap) < 0) exit(1); if (injail) { /* jail_attach won't chdir along with its chroot. */ path = string_param(j->intparams[KP_PATH]); if (path && chdir(path) < 0) { jail_warnx(j, "chdir %s: %s", path, strerror(errno)); exit(1); } if (int_param(j->intparams[IP_EXEC_FIB], &fib) && setfib(fib) < 0) { jail_warnx(j, "setfib: %s", strerror(errno)); exit(1); } if (jail_attach(j->jid) < 0) { jail_warnx(j, "jail_attach: %s", strerror(errno)); exit(1); } } if (clean || username) { if (!(injail && sjuser) && get_user_info(j, username, &pwd, &lcap) < 0) exit(1); if (clean) { term = getenv("TERM"); environ = &cleanenv; setenv("PATH", "/bin:/usr/bin", 0); if (term != NULL) setenv("TERM", term, 1); } if (setusercontext(lcap, pwd, pwd->pw_uid, username ? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN : LOGIN_SETPATH | LOGIN_SETENV) < 0) { jail_warnx(j, "setusercontext %s: %s", pwd->pw_name, strerror(errno)); exit(1); } login_close(lcap); setenv("USER", pwd->pw_name, 1); setenv("HOME", pwd->pw_dir, 1); setenv("SHELL", *pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1); if (clean && chdir(pwd->pw_dir) < 0) { jail_warnx(j, "chdir %s: %s", pwd->pw_dir, strerror(errno)); exit(1); } endpwent(); } if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) { jail_warnx(j, "exec.consolelog: %s", strerror(errno)); exit(1); } closefrom(3); execvp(argv[0], argv); jail_warnx(j, "exec %s: %s", argv[0], strerror(errno)); exit(1); } /* * Add a process to the hash, tied to a jail. */ static int add_proc(struct cfjail *j, pid_t pid) { struct kevent ke; struct cfjail *tj; struct phash *ph; if (!kq && (kq = kqueue()) < 0) err(1, "kqueue"); EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL); if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0) { if (errno == ESRCH) return 0; err(1, "kevent"); } ph = emalloc(sizeof(struct phash)); ph->j = j; ph->pid = pid; LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le); j->nprocs++; j->flags |= JF_SLEEPQ; if (j->timeout.tv_sec == 0) requeue(j, &sleeping); else { /* File the jail in the sleep queue acording to its timeout. */ TAILQ_REMOVE(j->queue, j, tq); TAILQ_FOREACH(tj, &sleeping, tq) { if (!tj->timeout.tv_sec || j->timeout.tv_sec < tj->timeout.tv_sec || (j->timeout.tv_sec == tj->timeout.tv_sec && j->timeout.tv_nsec <= tj->timeout.tv_nsec)) { TAILQ_INSERT_BEFORE(tj, j, tq); break; } } if (tj == NULL) TAILQ_INSERT_TAIL(&sleeping, j, tq); j->queue = &sleeping; } return 1; } /* * Remove any processes from the hash that correspond to a jail. */ static void clear_procs(struct cfjail *j) { struct kevent ke; struct phash *ph, *tph; int i; j->nprocs = 0; for (i = 0; i < PHASH_SIZE; i++) LIST_FOREACH_SAFE(ph, &phash[i], le, tph) if (ph->j == j) { EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE, NOTE_EXIT, 0, NULL); (void)kevent(kq, &ke, 1, NULL, 0, NULL); LIST_REMOVE(ph, le); free(ph); } } /* * Find the jail that corresponds to an exited process. */ static struct cfjail * find_proc(pid_t pid) { struct cfjail *j; struct phash *ph; LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le) if (ph->pid == pid) { j = ph->j; LIST_REMOVE(ph, le); free(ph); return --j->nprocs ? NULL : j; } return NULL; } /* * Send SIGTERM to all processes in a jail and wait for them to die. */ static int term_procs(struct cfjail *j) { struct kinfo_proc *ki; int i, noted, pcnt, timeout; static kvm_t *kd; if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout)) timeout = DEFAULT_STOP_TIMEOUT; else if (timeout == 0) return 0; if (kd == NULL) { kd = kvm_open(NULL, NULL, NULL, O_RDONLY, NULL); if (kd == NULL) return 0; } ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt); if (ki == NULL) return 0; noted = 0; for (i = 0; i < pcnt; i++) if (ki[i].ki_jid == j->jid && kill(ki[i].ki_pid, SIGTERM) == 0) { (void)add_proc(j, ki[i].ki_pid); if (verbose > 0) { if (!noted) { noted = 1; jail_note(j, "sent SIGTERM to:"); } printf(" %d", ki[i].ki_pid); } } if (noted) printf("\n"); if (j->nprocs > 0) { clock_gettime(CLOCK_REALTIME, &j->timeout); j->timeout.tv_sec += timeout; return 1; } return 0; } /* * Look up a user in the passwd and login.conf files. */ static int get_user_info(struct cfjail *j, const char *username, const struct passwd **pwdp, login_cap_t **lcapp) { const struct passwd *pwd; *pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid()); if (pwd == NULL) { if (errno) jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "", username ? username : "", strerror(errno)); else if (username) jail_warnx(j, "%s: no such user", username); else jail_warnx(j, "unknown uid %d", getuid()); return -1; } *lcapp = login_getpwclass(pwd); if (*lcapp == NULL) { jail_warnx(j, "getpwclass %s: %s", pwd->pw_name, strerror(errno)); return -1; } /* Set the groups while the group file is still available */ if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) { jail_warnx(j, "initgroups %s: %s", pwd->pw_name, strerror(errno)); return -1; } return 0; } /* * Make sure a mount or consolelog path is a valid absolute pathname * with no symlinks. */ static int check_path(struct cfjail *j, const char *pname, const char *path, int isfile, const char *umount_type) { struct stat st, mpst; struct statfs stfs; char *tpath, *p; const char *jailpath; size_t jplen; if (path[0] != '/') { jail_warnx(j, "%s: %s: not an absolute pathname", pname, path); return -1; } /* * Only check for symlinks in components below the jail's path, * since that's where the security risk lies. */ jailpath = string_param(j->intparams[KP_PATH]); if (jailpath == NULL) jailpath = ""; jplen = strlen(jailpath); if (!strncmp(path, jailpath, jplen) && path[jplen] == '/') { tpath = alloca(strlen(path) + 1); strcpy(tpath, path); for (p = tpath + jplen; p != NULL; ) { p = strchr(p + 1, '/'); if (p) *p = '\0'; if (lstat(tpath, &st) < 0) { if (errno == ENOENT && isfile && !p) break; jail_warnx(j, "%s: %s: %s", pname, tpath, strerror(errno)); return -1; } if (S_ISLNK(st.st_mode)) { jail_warnx(j, "%s: %s is a symbolic link", pname, tpath); return -1; } if (p) *p = '/'; } } if (umount_type != NULL) { if (stat(path, &st) < 0 || statfs(path, &stfs) < 0) { jail_warnx(j, "%s: %s: %s", pname, path, strerror(errno)); return -1; } if (stat(stfs.f_mntonname, &mpst) < 0) { jail_warnx(j, "%s: %s: %s", pname, stfs.f_mntonname, strerror(errno)); return -1; } if (st.st_ino != mpst.st_ino) { jail_warnx(j, "%s: %s: not a mount point", pname, path); return -1; } if (strcmp(stfs.f_fstypename, umount_type)) { jail_warnx(j, "%s: %s: not a %s mount", pname, path, umount_type); return -1; } } return 0; }