/* SAMHAIN file system integrity testing */ /* Copyright (C) 2000,2004 Rainer Wichmann */ /* */ /* This program is free software; you can redistribute it */ /* and/or modify */ /* it under the terms of the GNU General Public License as */ /* published by */ /* the Free Software Foundation; either version 2 of the License, or */ /* (at your option) any later version. */ /* */ /* This program is distributed in the hope that it will be useful, */ /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */ /* GNU General Public License for more details. */ /* */ /* You should have received a copy of the GNU General Public License */ /* along with this program; if not, write to the Free Software */ /* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "config_xor.h" #include #include #ifdef HAVE_MEMORY_H #include #endif /* replace #if 0 by #if 1 and set an appropriate path in front of '/pdbg.' * for debugging */ #if 0 #define PDGBFILE "/pdbg." #endif #if defined(PDGBFILE) static FILE * pdbg = NULL; static FILE * pdbgc = NULL; #define PDBG_OPEN if (pdbg == NULL) pdbg = fopen(PDGBFILE"main", "a") #define PDBG_CLOSE sl_fclose (FIL__, __LINE__, pdbg); pdbg = NULL #define PDBG(arg) fprintf(pdbg, "PDBG: step %d\n", arg); fflush(pdbg) #define PDBG_D(arg) fprintf(pdbg, "PDBG: %d\n", arg); fflush(pdbg) #define PDBG_S(arg) fprintf(pdbg, "PDBG: %s\n", arg); fflush(pdbg) #define PDBGC_OPEN if (pdbgc == NULL) pdbgc = fopen(PDGBFILE"child", "a") #define PDBGC_CLOSE sl_fclose (FIL__, __LINE__, pdbgc); pdbgc = NULL #define PDBGC(arg) fprintf(pdbgc, "PDBGC: step %d\n", arg); fflush(pdbgc) #define PDBGC_D(arg) fprintf(pdbgc, "PDBGC: %d\n", arg); fflush(pdbgc) #define PDBGC_S(arg) fprintf(pdbgc, "PDBGC: %s\n", arg); fflush(pdbgc) #else #define PDBG_OPEN #define PDBG_CLOSE #define PDBG(arg) #define PDBG_D(arg) #define PDBG_S(arg) #define PDBGC_OPEN #define PDBGC_CLOSE #define PDBGC(arg) #define PDBGC_D(arg) #define PDBGC_S(arg) #endif #include #include #include #include #include #include #include #include #include #if HAVE_SYS_TIME_H #include #endif #include #include "samhain.h" #include "sh_utils.h" #include "sh_unix.h" #include "sh_tiger.h" #include "sh_extern.h" #include "sh_calls.h" #include "sh_filter.h" #define SH_NEED_PWD_GRP 1 #include "sh_static.h" #undef FIL__ #define FIL__ _("sh_extern.c") extern int get_the_fd (SL_TICKET ticket); /* * -- generic safe popen */ int sh_ext_popen (sh_tas_t * task) { long status = 0; int flags; char * tmp; char * tmp2; int errnum; int pipedes[2]; FILE * outf = NULL; char * envp[1]; char * argp[2]; char * errfile; char errbuf[SH_ERRBUF_SIZE]; static int some_error = 0; #if defined (__linux__) SL_TICKET fd = -1; char pname[128]; int pfd = -1; #endif SL_ENTER(_("sh_ext_popen")); /* Linux, HP-UX and FreeBSD will happily accept envp = argp = NULL * (newer Linuxes (gcc 4.4.4) warn on argp == NULL, but accept it, * as reported by T. Luettgert) * Solaris (and probably some other Unices) * needs a valid *envp[] with envp[0] = NULL; * and similarly for argp * OpenBSD finally needs non-null argp[0] ... */ argp[0] = task->command; argp[1] = NULL; envp[0] = NULL; /* * -- check whether path is trustworthy */ status = sl_trustfile(task->command, NULL, NULL); #if 0 if ((uid_t) -1 != task->trusted_users[0]) { status = sl_trustfile(task->command, task->trusted_users, NULL); } #endif PDBG_OPEN; PDBG_D( (int) status); if ( SL_ENONE != status) { PDBG_S("SL_ENONE != status"); if (some_error == 0) { tmp = sh_util_safe_name (task->command); errfile = sl_trust_errfile(); if (errfile[0] != '\0') { tmp2 = sh_util_safe_name (sl_trust_errfile()); sh_error_handle((-1), FIL__, __LINE__, status, MSG_E_TRUST2, sl_error_string((int)status), tmp, tmp2); SH_FREE(tmp2); } else { sh_error_handle((-1), FIL__, __LINE__, status, MSG_E_TRUST1, sl_error_string((int)status), tmp); } SH_FREE(tmp); } some_error = 1; SL_RETURN ((-1), _("sh_ext_popen")); } PDBG(1); /* * -- check whether the checksum is correct; with linux emulate fdexec */ #if ( !defined(__linux__) || ( defined(__linux__) && defined(HAVE_PTHREAD)) ) && !defined(SL_DEBUG) if (task->checksum[0] != '\0') { char hashbuf[KEYBUF_SIZE]; PDBG_S("checksum test"); if (0 != sl_strcmp(task->checksum, sh_tiger_hash (task->command, TIGER_FILE, TIGER_NOLIM, hashbuf, sizeof(hashbuf)) ) ) { PDBG_S("checksum mismatch"); if (some_error == 0) { tmp = sh_util_safe_name (task->command); sh_error_handle((-1), FIL__, __LINE__, 0, MSG_E_HASH, tmp); SH_FREE(tmp); } some_error = 1; SL_RETURN ((-1), _("sh_ext_popen")); } } #endif some_error = 0; PDBG(2); /* * -- Create the pipe */ if (aud_pipe(FIL__, __LINE__, pipedes) < 0) { PDBG_S("pipe() failure"); errnum = errno; sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_E_SUBGEN, sh_error_message(errnum, errbuf, sizeof(errbuf)), _("pipe")); SL_RETURN ((-1), _("sh_ext_popen")); } PDBG(3); /* * -- Flush streams and fork */ fflush (NULL); task->pid = aud_fork(FIL__, __LINE__); if (task->pid == (pid_t) - 1) { PDBG_S("fork() failure"); /*@-usedef@*/ (void) sl_close_fd(FIL__, __LINE__, pipedes[0]); (void) sl_close_fd(FIL__, __LINE__, pipedes[1]); /*@+usedef@*/ errnum = errno; sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_E_SUBGEN, sh_error_message(errnum, errbuf, sizeof(errbuf)), _("fork")); SL_RETURN ((-1), _("sh_ext_popen")); } PDBG(4); if (task->pid == (pid_t) 0) { /* * -- fork again, if requested */ if (S_TRUE == task->fork_twice) { task->pid = fork(); if (task->pid == (pid_t) - 1) { _exit (EXIT_FAILURE); } } if (task->pid == (pid_t) 0) { int val_return; PDBGC_OPEN; PDBGC(1); /* * -- grandchild - make write side of the pipe stdin */ if (task->rw == 'w') { do { val_return = dup2 (pipedes[STDIN_FILENO], STDIN_FILENO); } while (val_return < 0 && errno == EINTR); if (val_return < 0) _exit(EXIT_FAILURE); } else { do { val_return = dup2 (pipedes[STDOUT_FILENO], STDOUT_FILENO); } while (val_return < 0 && errno == EINTR); if (val_return < 0) _exit(EXIT_FAILURE); } PDBGC(2); /* close the pipe descriptors */ (void) sl_close_fd (FIL__, __LINE__, pipedes[STDIN_FILENO]); (void) sl_close_fd (FIL__, __LINE__, pipedes[STDOUT_FILENO]); /* don't leak file descriptors */ #if !defined(PDGBFILE) sh_unix_closeall (3, task->com_fd, S_TRUE); /* in child process */ #endif /* drop root privileges, if possible && requested */ if (task->privileged == 0 && 0 == getuid()) { PDBGC_S("privileged"); /* zero priv info */ memset(skey, 0, sizeof(sh_key_t)); if (setgid((gid_t) task->run_user_gid) != 0) _exit(EXIT_FAILURE); if (setuid((uid_t) task->run_user_uid) != 0) _exit(EXIT_FAILURE); /* make sure we cannot get root again */ if (setuid(0) >= 0) _exit(EXIT_FAILURE); } PDBGC(3); (void) fflush(NULL); if (task->rw == 'w') { PDBGC_S("w"); (void) fcntl (STDOUT_FILENO, F_SETFD, FD_CLOEXEC); (void) fcntl (STDERR_FILENO, F_SETFD, FD_CLOEXEC); /* freopen(_("/dev/null"), "r+", stderr); freopen(_("/dev/null"), "r+", stdout); */ } else { PDBGC_S("r"); do { val_return = dup2 (STDOUT_FILENO, STDERR_FILENO); } while (val_return < 0 && errno == EINTR); (void) fcntl (STDIN_FILENO, F_SETFD, FD_CLOEXEC); /* freopen(_("/dev/null"), "r+", stdin); */ } PDBGC(4); #if defined(__linux__) /* * -- emulate an fdexec with checksum testing */ #if !defined(HAVE_PTHREAD) if (task->checksum[0] != '\0') #endif { PDBGC_S("fexecve"); if (task->com_fd != (-1)) { do { val_return = dup (task->com_fd); } while (val_return < 0 && errno == EINTR); pfd = val_return; if (pfd < 0) { PDBGC_S("fexecve: dup failed"); _exit(EXIT_FAILURE); } } #if !defined(HAVE_PTHREAD) else { char hashbuf[KEYBUF_SIZE]; fd = sl_open_read(FIL__, __LINE__, task->command, task->privileged==0 ? SL_NOPRIV : SL_YESPRIV); if (0 != sl_strcmp(task->checksum, sh_tiger_hash (task->command, fd, TIGER_NOLIM, hashbuf, sizeof(hashbuf)))) { PDBGC_S("fexecve: checksum mismatch"); sl_close(fd); _exit(EXIT_FAILURE); } pfd = get_the_fd(fd); do { val_return = dup (pfd); } while (val_return < 0 && errno == EINTR); pfd = val_return; sl_close(fd); fd = -1; if (pfd < 0) { PDBGC_S("fexecve: dup (2) failed"); _exit(EXIT_FAILURE); } } #endif PDBGC(5); /* Cannot use sprintf because of deadlock in malloc/free */ { static char digit[] = "0123456789"; char str0[128]; char str1[128]; int ival = pfd; unsigned int n = 0; unsigned int m = 0; if (ival < 0) ival = -ival; do { str0[n] = digit[ival % 10]; ++n; ival /= 10; } while (ival); if (pfd < 0) { str0[n] = '-'; ++n; } str0[n] = '\0'; str1[n] = '\0'; while (n > 0) { str1[m] = str0[n-1]; ++m; --n; } sl_strlcpy(pname, _("/proc/self/fd/"), sizeof(pname)); sl_strlcat(pname, str1, sizeof(pname)); } if (access(pname, R_OK|X_OK) == 0) /* flawfinder: ignore */ { PDBGC(6); PDBGC_CLOSE; fcntl (pfd, F_SETFD, FD_CLOEXEC); do { val_return = execve (pname, (task->argc == 0) ? argp : task->argv, (task->envc == 0) ? NULL : task->envv ); } while (val_return < 0 && errno == EINTR); errnum = errno; PDBGC_OPEN; PDBGC_S(strerror(errnum)); PDBGC_S(task->command); PDBGC_S("fexecve: failed"); PDBGC_CLOSE; /* failed */ _exit((errnum == 0) ? (EXIT_SUCCESS) : (EXIT_FAILURE)); } PDBGC_S("fexecve: not working"); /* * procfs not working, go ahead; checksum is tested already */ if (fd != -1) sl_close(fd); else if (pfd != -1) sl_close_fd(FIL__, __LINE__, pfd); } #endif PDBGC_S(" -- non fexecve --"); /* * -- execute path if executable */ if (0 == access(task->command, R_OK|X_OK)) /* flawfinder: ignore */ { PDBGC(5); PDBGC_CLOSE; do { val_return = execve (task->command, (task->argc == 0) ? argp : task->argv, (task->envc == 0) ? envp : task->envv ); } while (val_return < 0 && errno == EINTR); } errnum = errno; PDBGC_OPEN; PDBGC_S(strerror(errnum)); PDBGC_S(task->command); PDBGC_S("execve: failed"); PDBGC_CLOSE; /* failed */ _exit((errnum == 0) ? (EXIT_SUCCESS) : (EXIT_FAILURE)); } /* * if we have forked twice, this is parent::detached_subprocess */ if (S_TRUE == task->fork_twice) { _exit (0); } } /* * -- parent; task->pid is child pid; exit status is status of * grandchild if exited */ if (S_TRUE == task->fork_twice) { (void) waitpid (task->pid, NULL, 0); } PDBG(5); /* open an output stream on top of the write side of the pipe */ if (task->rw == 'w') { PDBG_S("is w"); (void) sl_close_fd (FIL__, __LINE__, pipedes[STDIN_FILENO]); (void) retry_fcntl (FIL__, __LINE__, pipedes[STDOUT_FILENO], F_SETFD, FD_CLOEXEC); outf = fdopen (pipedes[STDOUT_FILENO], "w"); } else { PDBG_S("is r"); (void) sl_close_fd (FIL__, __LINE__, pipedes[STDOUT_FILENO]); (void) retry_fcntl (FIL__, __LINE__, pipedes[STDIN_FILENO], F_SETFD, FD_CLOEXEC); outf = fdopen (pipedes[STDIN_FILENO], "r"); } if (outf == NULL) { errnum = errno; PDBG_S("outf == NULL"); tmp = sh_util_safe_name (task->command); if (task->privileged == 0 && 0 == getuid()) sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_NOEXEC, (UID_CAST) task->run_user_uid, tmp); else sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_NOEXEC, (UID_CAST) getuid(), tmp); SH_FREE(tmp); (void) aud_kill (FIL__, __LINE__, task->pid, SIGKILL); (void) sl_close_fd (FIL__, __LINE__, pipedes[STDOUT_FILENO]); (void) sl_close_fd (FIL__, __LINE__, pipedes[STDIN_FILENO]); (void) waitpid (task->pid, NULL, 0); task->pid = 0; SL_RETURN ((-1), _("sh_ext_popen")); } if (task->rw == 'w') task->pipeFD = pipedes[STDOUT_FILENO]; else task->pipeFD = pipedes[STDIN_FILENO]; PDBG_D(task->pipeFD); task->pipeTI = sl_make_ticket(FIL__, __LINE__, task->pipeFD, _("pipe"), outf); flags = (int) retry_fcntl (FIL__, __LINE__, task->pipeFD, F_GETFL, 0); if (flags != (-1)) (void) retry_fcntl (FIL__, __LINE__, task->pipeFD, F_SETFL, flags|O_NONBLOCK); task->pipe = outf; PDBG_S("return from popen"); PDBG_CLOSE; SL_RETURN (0, _("sh_ext_popen")); } /* * -- close the pipe */ extern int flag_err_debug; int sh_ext_pclose (sh_tas_t * task) { int status = 0; int retry = 0; pid_t retval; char infomsg[256]; #ifdef WCONTINUED int wflags = WNOHANG|WUNTRACED|WCONTINUED; #else int wflags = WNOHANG|WUNTRACED; #endif SL_ENTER(_("sh_ext_pclose")); PDBG_OPEN; PDBG_S(" -> pclose"); (void) fflush(task->pipe); if (!SL_ISERROR(task->pipeTI)) (void) sl_close(task->pipeTI); task->pipe = NULL; task->pipeFD = (-1); task->pipeTI = SL_ETICKET; if (S_FALSE == task->fork_twice) { infomsg[0] = '\0'; nochmal: retval = waitpid(task->pid, &(task->exit_status), wflags); /*@-bufferoverflowhigh@*/ if (task->pid == retval) { #ifndef USE_UNO if (WIFEXITED(task->exit_status) != 0) { task->exit_status = WEXITSTATUS(task->exit_status); if ((flag_err_debug == S_TRUE) || (task->exit_status != 0)) sl_snprintf(infomsg, sizeof(infomsg), _("Subprocess exited normally with status %d"), task->exit_status); } else if (WIFSIGNALED(task->exit_status) != 0) { sl_snprintf(infomsg, sizeof(infomsg), _("Subprocess terminated by signal %d"), WTERMSIG(task->exit_status)); task->exit_status = EXIT_FAILURE; } else if (WIFSTOPPED(task->exit_status) != 0) { sl_snprintf(infomsg, sizeof(infomsg), _("Subprocess stopped by signal %d, killing"), WSTOPSIG(task->exit_status)); task->exit_status = EXIT_FAILURE; (void) aud_kill (FIL__, __LINE__, task->pid, 9); (void) retry_msleep (0, 30); (void) waitpid (task->pid, NULL, wflags); } else { sl_snprintf(infomsg, sizeof(infomsg), _("Subprocess exit status unknown")); task->exit_status = EXIT_FAILURE; } #else task->exit_status = EXIT_FAILURE; #endif } else if (0 == retval) { if (retry < 3) { ++retry; (void) retry_msleep(0, (retry * 30)); goto nochmal; } (void) aud_kill (FIL__, __LINE__, task->pid, 9); sl_snprintf(infomsg, sizeof(infomsg), _("Subprocess not yet exited, killing")); task->exit_status = EXIT_FAILURE; (void) waitpid (task->pid, NULL, 0); } else { sl_snprintf(infomsg, sizeof(infomsg), _("Waitpid returned error %d\n"), errno); task->exit_status = EXIT_FAILURE; } /*@+bufferoverflowhigh@*/ status = task->exit_status; if (flag_err_debug == S_TRUE) { sh_error_handle(SH_ERR_ALL, FIL__, __LINE__, task->exit_status, MSG_E_SUBGEN, infomsg, _("sh_ext_pclose")); } else if (status != 0) { sh_error_handle(SH_ERR_INFO, FIL__, __LINE__, task->exit_status, MSG_E_SUBGEN, infomsg, _("sh_ext_pclose")); } } task->pid = 0; task->exit_status = 0; PDBG_S(" <--"); PDBG_CLOSE; SL_RETURN (status, _("sh_ext_pclose")); } void sh_ext_tas_init (sh_tas_t * tas) { int i; tas->command = NULL; tas->argc = 0; tas->envc = 0; tas->checksum[0] = '\0'; tas->pipeFD = (-1); tas->pipeTI = SL_ETICKET; tas->pid = (pid_t) -1; tas->privileged = 1; tas->pipe = NULL; tas->rw = 'w'; tas->exit_status = 0; tas->fork_twice = S_TRUE; for (i = 0; i < 32; ++i) { tas->argv[i] = NULL; tas->envv[i] = NULL; #if 0 tas->trusted_users[i] = (uid_t) -1; #endif } tas->run_user_uid = (uid_t) getuid(); tas->run_user_gid = (gid_t) getgid(); tas->com_fd = -1; tas->com_ti = -1; return; } int sh_ext_tas_add_envv(sh_tas_t * tas, const char * key, const char * val) { size_t sk = 0, sv = 0; int si; SL_ENTER(_("sh_ext_tas_add_envv")); if (tas == NULL || (key == NULL && val == NULL) || tas->envc >= 30) { SL_RETURN (-1, _("sh_ext_tas_add_envv")); } if (key != NULL) sk = strlen(key) + 1; if (val != NULL) sv = strlen(val) + 1; if (!sl_ok_adds(sk, sv)) { SL_RETURN (-1, _("sh_ext_tas_add_envv")); } si = tas->envc; tas->envv[si] = SH_ALLOC(sk + sv); if (key != NULL) { (void) sl_strlcpy(tas->envv[si], key, sk+sv); (void) sl_strlcat(tas->envv[si], "=", sk+sv); if (val != NULL) (void) sl_strlcat(tas->envv[si], val, sk+sv); } else (void) sl_strlcpy(tas->envv[si], val, sv); ++(tas->envc); SL_RETURN ((tas->envc), _("sh_ext_tas_add_envv")); } int sh_ext_tas_rm_argv(sh_tas_t * tas) { int last; SL_ENTER(_("sh_ext_tas_rm_argv")); if (tas == NULL || tas->argc == 0) { SL_RETURN (-1, _("sh_ext_tas_rm_argv")); } last = (tas->argc - 1); --(tas->argc); SH_FREE(tas->argv[last]); tas->argv[last] = NULL; SL_RETURN ((tas->argc), _("sh_ext_tas_rm_argv")); } int sh_ext_tas_add_argv(sh_tas_t * tas, const char * val) { size_t sv = 0; int si; SL_ENTER(_("sh_ext_tas_add_argv")); if (tas == NULL || val == NULL || tas->argc >= 30) { SL_RETURN (-1, _("sh_ext_tas_add_argv")); } if (val != NULL) sv = strlen(val) + 1; si = tas->argc; tas->argv[si] = SH_ALLOC(sv); (void) sl_strlcpy(tas->argv[si], val, sv); ++(tas->argc); SL_RETURN ((tas->argc), _("sh_ext_tas_add_argv")); } void sh_ext_tas_command(sh_tas_t * tas, const char * command) { size_t len = sl_strlen(command); tas->command = SH_ALLOC(len+1); (void) sl_strlcpy(tas->command, command, len+1); return; } void sh_ext_tas_free(sh_tas_t * tas) { int i; if (NULL != tas->command) SH_FREE(tas->command); for (i = 0; i < 32; ++i) { if (NULL != tas->argv[i]) SH_FREE(tas->argv[i]); if (NULL != tas->envv[i]) SH_FREE(tas->envv[i]); } if (tas->com_ti != (-1)) { (void) sl_close(tas->com_ti); tas->com_ti = -1; tas->com_fd = -1; } return; } static void task_init (sh_tas_t * task) { sh_ext_tas_init(task); (void) sh_ext_tas_add_envv (task, _("SHELL"), _("/bin/sh")); (void) sh_ext_tas_add_envv (task, _("PATH"), _("/sbin:/bin:/usr/sbin:/usr/bin:/usr/ucb")); (void) sh_ext_tas_add_envv (task, _("IFS"), " \n\t"); if (sh.timezone != NULL) { (void) sh_ext_tas_add_envv(task, "TZ", sh.timezone); } return; } int sh_ext_popen_init (sh_tas_t * task, const char * command, char * argv0, ...) { va_list vl; int status; task_init (task); if (!argv0) { sh_ext_tas_command(task, _("/bin/sh")); (void) sh_ext_tas_add_argv(task, _("/bin/sh")); (void) sh_ext_tas_add_argv(task, _("-c")); (void) sh_ext_tas_add_argv(task, command); } else { char * s; sh_ext_tas_command(task, command); (void) sh_ext_tas_add_argv(task, argv0); va_start (vl, argv0); s = va_arg (vl, char * ); while (s != NULL) { (void) sh_ext_tas_add_argv(task, s); s = va_arg (vl, char * ); } va_end (vl); } task->rw = 'r'; task->fork_twice = S_FALSE; status = sh_ext_popen(task); return status; } /* Execute a system command */ int sh_ext_system (char * command, char * argv0, ...) { sh_tas_t task; int status; va_list vl; char * s; SL_ENTER(_("sh_ext_system")); task_init (&task); sh_ext_tas_command(&task, command); (void) sh_ext_tas_add_argv(&task, argv0); va_start (vl, argv0); s = va_arg (vl, char * ); while (s != NULL) { (void) sh_ext_tas_add_argv(&task, s); s = va_arg (vl, char * ); } va_end (vl); task.rw = 'r'; task.fork_twice = S_FALSE; status = sh_ext_popen(&task); if (status != 0) { sh_error_handle(SH_ERR_ERR, FIL__, __LINE__, status, MSG_E_SUBGEN, _("Could not execute command"), _("sh_ext_system")); SL_RETURN ((-1), _("sh_ext_system")); } /* close pipe and return exit status */ (void) sh_ext_pclose(&task); sh_ext_tas_free (&task); SL_RETURN ((status), _("sh_ext_system")); } /* Execute command, return first line of output * ifconfig | grep -1 lo | tail -n 1 | sed s/.*inet addr:\([0-9.]*\)\(.*\)/\1/ */ char * sh_ext_popen_str (const char * command) { sh_tas_t task; struct sigaction new_act; struct sigaction old_act; char * out = NULL; int status; SL_ENTER(_("sh_ext_popen_str")); status = sh_ext_popen_init (&task, command, NULL, NULL); if (status != 0) { sh_error_handle(SH_ERR_ALL, FIL__, __LINE__, status, MSG_E_SUBGEN, _("Could not open pipe"), _("sh_ext_popen_str")); SL_RETURN ((NULL), _("sh_ext_popen_str")); } /* ignore SIGPIPE (instead get EPIPE if connection is closed) */ new_act.sa_handler = SIG_IGN; new_act.sa_flags = 0; sigemptyset( &new_act.sa_mask ); (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &new_act, &old_act); /* read from the open pipe */ if (task.pipe != NULL) { int try = 1200; /* 1000 * 0.1 = 120 sec */ sh_string * s = sh_string_new(0); do { sh_string_read(s, task.pipe, 0); if (sh_string_len(s) == 0) { /* cppcheck-suppress syntaxError */ --try; retry_msleep(0, 100); } } while (sh_string_len(s) == 0 && try != 0); if (sh_string_len(s) == 0) { sh_error_handle(SH_ERR_ALL, FIL__, __LINE__, status, MSG_E_SUBGEN, _("No output from command"), _("sh_ext_popen_str")); } out = sh_util_strdup(sh_string_str(s)); sh_string_destroy(&s); } /* restore old signal handler */ (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &old_act, NULL); /* close pipe and return exit status */ (void) sh_ext_pclose(&task); sh_ext_tas_free (&task); SL_RETURN ((out), _("sh_ext_popen_str")); } /* --------------- EXTERN STUFF ------------------- */ #if defined(WITH_EXTERNAL) typedef struct _sh_com_t { char type[4]; sh_filter_type * filter; time_t deadtime; time_t last_run; sh_tas_t tas; struct _sh_com_t * next; } sh_com_t; static void set3 (char * pos, char c1, char c2, char c3) { pos[0] = c1; pos[1] = c2; pos[2] = c3; pos[3] = '\0'; return; } /* initialize the external command structure */ static sh_com_t * command_init(void) { uid_t ff_euid; sh_com_t * ext_com = NULL; SL_ENTER(_("command_init")); ext_com = (sh_com_t *) SH_ALLOC(sizeof(sh_com_t)); if (!ext_com) { SL_RETURN( NULL, _("command_init")); } sh_ext_tas_init (&(ext_com->tas)); (void) sl_get_euid(&ff_euid); #if 0 ext_com->tas.trusted_users[0] = (uid_t) 0; ext_com->tas.trusted_users[1] = (uid_t) (ff_euid); #endif /* ------------------------------------------------- */ set3(ext_com->type, 'l', 'o', 'g'); ext_com->filter = NULL; ext_com->deadtime = 0; ext_com->last_run = 0; ext_com->next = NULL; SL_RETURN( ext_com, _("command_init")); } /* the list of external commands */ static sh_com_t * ext_coms = NULL; /* if -1, allocation of last command has failed, * thus don't fill in options */ static int ext_failed = -1; static int sh_ext_add_envv(const char * key, const char * val) { int retval; SL_ENTER(_("sh_ext_add_envv")); if (ext_coms == NULL || ext_failed == (-1) || (key == NULL && val == NULL) || ext_coms->tas.envc >= 30) { SL_RETURN (-1, _("sh_ext_add_envv")); } retval = sh_ext_tas_add_envv(&(ext_coms->tas), key, val); if (retval >= 0) retval = 0; SL_RETURN (retval, _("sh_ext_add_envv")); } static int sh_ext_init(const char * command) { sh_com_t * retval; size_t size; SL_ENTER(_("sh_ext_init")); if (command == NULL) { SL_RETURN (-1, _("sh_ext_init")); } size = strlen(command); if (command[0] != '/' || size < 2) { SL_RETURN (-1, _("sh_ext_init")); } if (NULL == (retval = command_init())) { SL_RETURN (-1, _("sh_ext_init")); } sh_ext_tas_command(&(retval->tas), command); if (sh.timezone != NULL) { (void) sh_ext_add_envv( "TZ", sh.timezone); } retval->next = ext_coms; ext_coms = retval; SL_RETURN (0, _("sh_ext_init")); } static int sh_ext_uid (const char * user, /*@out@*/uid_t * uid, /*@out@*/gid_t * gid) { struct passwd * tempres; #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_GETPWNAM_R) struct passwd pwd; char * buffer = SH_ALLOC(SH_PWBUF_SIZE); #endif SL_ENTER(_("sh_ext_uid")); *uid = (uid_t)-1; *gid = (gid_t)-1; if (user == NULL) { #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_GETPWNAM_R) SH_FREE(buffer); #endif SL_RETURN (-1, _("sh_ext_uid")); } #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_GETPWNAM_R) sh_getpwnam_r(user, &pwd, buffer, SH_PWBUF_SIZE, &tempres); #else tempres = sh_getpwnam(user); #endif if (NULL != tempres) { *uid = tempres->pw_uid; *gid = tempres->pw_gid; #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_GETPWNAM_R) SH_FREE(buffer); #endif SL_RETURN (0, _("sh_ext_uid")); } #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_GETPWNAM_R) SH_FREE(buffer); #endif SL_RETURN (-1, _("sh_ext_uid")); } static int sh_ext_add (const char * argstring, int * ntok, char * stok[]) { int i = 0; size_t s; char * p; char * new; size_t len; SL_ENTER(_("sh_ext_add")); if (NULL == argstring) { SL_RETURN((-1), _("sh_ext_add")); } len = strlen(argstring) + 1; new = SH_ALLOC(len); sl_strlcpy(new, argstring, len); do { #if defined(HAVE_PTHREAD) && defined (_POSIX_THREAD_SAFE_FUNCTIONS) && defined(HAVE_STRTOK_R) char * saveptr; if (i == 0) p = strtok_r (new, ", \t", &saveptr); else p = strtok_r (NULL, ", \t", &saveptr); #else if (i == 0) p = strtok (new, ", \t"); else p = strtok (NULL, ", \t"); #endif if (p == NULL) break; s = strlen(p) + 1; if (stok[i] != NULL) SH_FREE(stok[i]); stok[i] = SH_ALLOC(s); (void) sl_strlcpy(stok[i], p, s); ++i; if (i == 30) break; } while (p != NULL); *ntok = i; SH_FREE(new); SL_RETURN (0, _("sh_ext_add")); } /********************************************************* * * Public functions * * *********************************************************/ /* * -- start a new external command, and add it to the list */ int sh_ext_setcommand(const char * cmd) { int i; SL_ENTER(_("sh_ext_setcommand")); if ( (i = sh_ext_init(cmd)) < 0) ext_failed = -1; else ext_failed = 0; SL_RETURN( i, _("sh_ext_setcommand")); } /* * -- clean up the command list */ int sh_ext_cleanup(void) { sh_com_t * retval; SL_ENTER(_("sh_ext_cleanup")); while (ext_coms != NULL) { retval = ext_coms; ext_coms = retval->next; sh_ext_tas_free (&(retval->tas)); if (retval->filter) sh_filter_free (retval->filter); SH_FREE(retval); } SL_RETURN (0, _("sh_ext_cleanup")); } /* * -- explicitely close a command */ int sh_ext_close_command (const char * str) { (void) str; if (ext_coms == NULL || ext_failed == (-1)) return (-1); ext_failed = (-1); return 0; } /* * -- add keywords to the OR filter */ int sh_ext_add_or (const char * str) { if (ext_coms == NULL || ext_failed == (-1)) return (-1); if (ext_coms->filter == NULL) ext_coms->filter = sh_filter_alloc(); return (sh_filter_add(str, ext_coms->filter, SH_FILT_OR)); } /* * -- add keywords to the AND filter */ int sh_ext_add_and (const char * str) { if (ext_coms == NULL || ext_failed == (-1)) return (-1); if (ext_coms->filter == NULL) ext_coms->filter = sh_filter_alloc(); return (sh_filter_add(str, ext_coms->filter, SH_FILT_AND)); } /* * -- add keywords to the NOT filter */ int sh_ext_add_not (const char * str) { if (ext_coms == NULL || ext_failed == (-1)) return (-1); if (ext_coms->filter == NULL) ext_coms->filter = sh_filter_alloc(); return (sh_filter_add(str, ext_coms->filter, SH_FILT_NOT)); } /* * -- add keywords to the CL argument list */ int sh_ext_add_argv (const char * str) { if (ext_coms == NULL || ext_failed == (-1)) return (-1); return (sh_ext_add (str, &(ext_coms->tas.argc), ext_coms->tas.argv)); } /* * -- add a path to the environment */ int sh_ext_add_default (const char * dummy) { char * p = NULL; int i; char dir[SH_PATHBUF]; SL_ENTER(_("sh_ext_add_default")); if (dummy[0] == 'n' || dummy[0] == 'N' || dummy[0] == 'f' || dummy[0] == 'F' || dummy[0] == '0') { SL_RETURN(0, _("sh_ext_add_default")); } p = sh_unix_getUIDdir (SH_ERR_ERR, (uid_t) ext_coms->tas.run_user_uid, dir, sizeof(dir)); if (p) (void) sh_ext_add_envv (_("HOME"), p); (void) sh_ext_add_envv (_("SHELL"), _("/bin/sh")); (void) sh_ext_add_envv (_("PATH"), _("/sbin:/bin:/usr/sbin:/usr/bin")); (void) sh_ext_add_envv (_("IFS"), " \n\t"); i = (p == NULL ? (-1) : 0); SL_RETURN(i, _("sh_ext_add_default")); } /* * -- add an environment variable */ int sh_ext_add_environ (const char * str) { int i; SL_ENTER(_("sh_ext_add_environ")); i = sh_ext_add_envv (NULL, str); SL_RETURN(i, _("sh_ext_add_environ")); } /* * -- set deadtime */ int sh_ext_deadtime (const char * str) { long deadtime = 0; char * tail = NULL; SL_ENTER(_("sh_ext_deadtime")); if (ext_coms == NULL || ext_failed == (-1) || str == NULL) { SL_RETURN (-1, _("sh_ext_deadtime")); } deadtime = strtol(str, &tail, 10); if (tail == str || deadtime < 0 || deadtime == LONG_MAX) { SL_RETURN (-1, _("sh_ext_deadtime")); } ext_coms->deadtime = (time_t) deadtime; SL_RETURN (0, _("sh_ext_deadtime")); } /* * -- define type */ int sh_ext_type (const char * str) { SL_ENTER(_("sh_ext_type")); if (ext_coms == NULL || ext_failed == (-1) || str == NULL) { SL_RETURN((-1), _("sh_ext_type")); } if (strlen(str) != 3) { SL_RETURN((-1), _("sh_ext_type")); } set3(ext_coms->type, str[0], str[1], str[2]); if (str[0] == 'l' && str[1] == 'o' && str[2] == 'g') ext_coms->tas.rw = 'w'; else if (str[0] == 's' && str[1] == 'r' && str[2] == 'v') ext_coms->tas.rw = 'w'; else if (str[0] == 'm' && str[1] == 'o' && str[2] == 'n') ext_coms->tas.rw = 'r'; else { SL_RETURN((-1), _("sh_ext_type")); } SL_RETURN(0, _("sh_ext_type")); } /* * -- define checksum */ int sh_ext_checksum (const char * str) { SL_ENTER(_("sh_ext_checksum")); if (ext_coms == NULL || ext_failed == (-1) || str == NULL) { SL_RETURN((-1), _("sh_ext_checksum")); } if (sl_strlen(str) != KEY_LEN) { SL_RETURN((-1), _("sh_ext_checksum")); } (void) sl_strlcpy (ext_coms->tas.checksum, str, KEY_LEN+1); SL_RETURN((0), _("sh_ext_checksum")); } /* * -- choose privileges */ int sh_ext_priv (const char * c) { uid_t me_uid; gid_t me_gid; SL_ENTER(_("sh_ext_priv")); if (0 == sh_ext_uid (c, &me_uid, &me_gid)) { ext_coms->tas.run_user_uid = me_uid; ext_coms->tas.run_user_gid = me_gid; if (me_uid != (uid_t) 0) ext_coms->tas.privileged = 0; SL_RETURN((0), _("sh_ext_priv")); } SL_RETURN (-1, _("sh_ext_priv")); } /* * -- check filters */ static int sh_ext_filter (char * message, sh_com_t * task) { time_t now_time; SL_ENTER(_("sh_ext_filter")); if (task->filter) { if (0 != sh_filter_filter (message, task->filter)) { SL_RETURN ((-1), _("sh_ext_filter")); } } /* Filter passed, check deadtime */ if (task->deadtime != (time_t) 0) { now_time = time (NULL); if (task->last_run == (time_t) 0) { task->last_run = now_time; } else if ((time_t)(now_time-task->last_run) < task->deadtime) { SL_RETURN ((-1), _("sh_ext_filter")); } else { task->last_run = now_time; } } SL_RETURN ((0), _("sh_ext_filter")); } /* * -- execute external script/program */ int sh_ext_execute (char t1, char t2, char t3, /*@null@*/char * message, size_t msg_siz) { int caperr; sh_com_t * listval = ext_coms; int status = 0; char * tmp; char errbuf[SH_ERRBUF_SIZE]; static int some_error = 0; struct sigaction new_act; struct sigaction old_act; SL_ENTER(_("sh_ext_execute")); PDBG_OPEN; if (listval == NULL || message == NULL) { SL_RETURN ((-1), _("sh_ext_execute")); } PDBG(-1); if (msg_siz == 0) msg_siz = sl_strlen(message); /* ignore SIGPIPE (instead get EPIPE if connection is closed) */ new_act.sa_handler = SIG_IGN; (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &new_act, &old_act); while (listval != NULL) { PDBG_OPEN; PDBG(-2); if (t1 == listval->type[0] && t2 == listval->type[1] && t3 == listval->type[2] && 0 == sh_ext_filter (message, listval)) { PDBG(-3); if (0 != (caperr = sl_get_cap_sub())) { sh_error_handle((-1), FIL__, __LINE__, caperr, MSG_E_SUBGEN, sh_error_message (caperr, errbuf, sizeof(errbuf)), _("sl_get_cap_sub")); } if (0 == sh_ext_popen (&(listval->tas))) { PDBG_OPEN; PDBG(-4); if (NULL != listval->tas.pipe && listval->tas.rw == 'w') { PDBG(-5); if (message != NULL) { PDBG(-6); status = (int) write (listval->tas.pipeFD, message, msg_siz); if (status >= 0) status = (int) write (listval->tas.pipeFD, "\n", 1); } PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "[", 1); PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "E", 1); PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "O", 1); PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "F", 1); PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "]", 1); PDBG_D(status); if (status >= 0) status = (int) write (listval->tas.pipeFD, "\n", 1); PDBG_D(status); if (status >= 0) { some_error = 0; } if ((status < 0) && (some_error == 0)) { some_error = 1; PDBG_S("some error"); PDBG_D(status); tmp = sh_util_safe_name (listval->tas.command); if (tmp) { if (listval->tas.privileged == 0 && (0 == getuid() || 0 != sl_is_suid()) ) sh_error_handle((-1), FIL__, __LINE__, 0, MSG_NOEXEC, (UID_CAST) listval->tas.run_user_uid, tmp); else sh_error_handle((-1), FIL__, __LINE__, 0, MSG_NOEXEC, (UID_CAST) getuid(), tmp); SH_FREE(tmp); } } PDBG(-7); (void) fflush(listval->tas.pipe); } PDBG(-8); (void) sh_ext_pclose(&(listval->tas)); } else { PDBG_OPEN; PDBG_S("0 != sh_ext_popen()"); } if (0 != (caperr = sl_drop_cap_sub())) { sh_error_handle((-1), FIL__, __LINE__, caperr, MSG_E_SUBGEN, sh_error_message (caperr, errbuf, sizeof(errbuf)), _("sl_drop_cap_sub")); } } listval = listval->next; } PDBG_OPEN; PDBG_S("no more commands"); /* restore old signal handler */ (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &old_act, NULL); PDBG_S("return"); PDBG_CLOSE; SL_RETURN ((0), _("sh_ext_execute")); } /* #if defined(WITH_EXTERNAL) */ #endif