/************************************************************************* * (C) 2009 AITNET - Sofia/Bulgaria - * by Michael Pounov * * $Author: misho $ * $Id: cfexec.c,v 1.3 2012/07/22 22:46:47 misho Exp $ * ************************************************************************* The ELWIX and AITNET software is distributed under the following terms: All of the documentation and software included in the ELWIX and AITNET Releases is copyrighted by ELWIX - Sofia/Bulgaria Copyright 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 by Michael Pounov . 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. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by Michael Pounov ELWIX - Embedded LightWeight unIX and its contributors. 4. Neither the name of AITNET nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY AITNET 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 REGENTS 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 "global.h" cfg_root_t cfg; int Verbose, Timeout, kq; ait_val_t User, Mount, Dev, Chroot; char szSess[MAXPATHLEN], szConfig[MAXPATHLEN]; extern char compiled[], compiledby[], compilehost[]; static void Usage() { printf( "CFExec is tool for managment R/W operation with CompactFlash\n" "=== %s === %s@%s ===\n\n" " Syntax: cfexec [options] [exec_file]\n\n" "\t-v\t\tVerbose ...\n" "\t-c \tAfter execute chroot to dir [default=/]\n" "\t-u \tAfter execute suid to user [default=root]\n" "\t-d \tOther device [default=/dev/ufs/elwix]\n" "\t-m \tOther mount dir [default=/cf]\n" "\t-t \tTimeout for autolock mount dir after seconds [default=300]\n" "\n", compiled, compiledby, compilehost); } static int update(int flags) { struct ufs_args mnt; memset(&mnt, 0, sizeof mnt); mnt.fspec = AIT_GET_STR(&Dev); #ifdef __NetBSD__ if (mount("ufs", AIT_GET_STR(&Mount), flags, &mnt, sizeof mnt) == -1) { #else if (mount("ufs", AIT_GET_STR(&Mount), flags, &mnt) == -1) { #endif printf("Error:: can`t update mount %s #%d - %s\n", AIT_GET_STR(&Mount), errno, strerror(errno)); return -1; } VERB(5) printf("Info(5):: safe mount for device %s to %s operation (%s)\n", AIT_GET_STR(&Dev), AIT_GET_STR(&Mount), (flags & MNT_RDONLY) ? "ro" : "rw"); return 0; } static void setuser() { struct passwd *pw; pw = getpwnam(AIT_GET_LIKE(&User, char*)); if (pw) { setuid(pw->pw_uid); setgid(pw->pw_gid); endpwent(); VERB(5) printf("Info(5):: Suid to user %s.\n", AIT_GET_STR(&User)); } else VERB(5) printf("Info(5):: Can`t suid to user %s !\n", AIT_GET_STR(&User)); } static int mkevent(struct kevent *chg, struct kevent *evt) { int f; char szStr[MAX_STR]; f = open(szSess, O_CREAT | O_WRONLY | O_TRUNC, 0644); if (f == -1) { printf("Error:: can`t lock session #%d - %s\n", errno, strerror(errno)); return -1; } else { memset(szStr, 0, MAX_STR); snprintf(szStr, MAX_STR, "%d", getpid()); write(f, szStr, strlen(szStr)); } VERB(3) printf("Created lock file %s\n", szSess); kq = kqueue(); if (kq == -1) { printf("Error:: can`t execute safe mount #%d - %s\n", errno, strerror(errno)); close(f); unlink(szSess); return -1; } else { memset(chg, 0, sizeof(struct kevent)); memset(evt, 0, sizeof(struct kevent)); EV_SET(chg, f, EVFILT_VNODE, EV_ADD, NOTE_DELETE | NOTE_RENAME | NOTE_REVOKE, 0, (intptr_t) NULL); } return f; } static void cleanexit() { AIT_FREE_VAL(&User); AIT_FREE_VAL(&Dev); AIT_FREE_VAL(&Mount); AIT_FREE_VAL(&Chroot); cfgUnloadConfig(&cfg); } int main(int argc, char **argv) { char ch; const char *err = NULL; struct kevent chg, evt; struct timespec ts; pid_t pid; int f, stat = 0; strlcpy(szConfig, DEFAULT_CONFIG, MAXPATHLEN); /* Load variables from config if exists */ if (!cfgLoadConfig(szConfig, &cfg)) { cfg_loadAttribute(&cfg, "cfexec", "timeout", &User, DEFAULT_TIMEOUT); #ifndef HAVE_STRTONUM Timeout = (int) strtol(szUser, NULL, 0); #else Timeout = strtonum(AIT_GET_STR(&User), 0, 3600, &err); #endif AIT_FREE_VAL(&User); if (!Timeout && err) { printf("Error:: in seconds for timeout %s - %s\n", optarg, err); cfgUnloadConfig(&cfg); return 1; } cfg_loadAttribute(&cfg, "cfexec", "suid", &User, DEFAULT_USER); cfg_loadAttribute(&cfg, "cfexec", "mount", &Mount, DEFAULT_MOUNT); cfg_loadAttribute(&cfg, "cfexec", "device", &Dev, DEFAULT_DEVICE); cfg_loadAttribute(&cfg, "cfexec", "chroot", &Chroot, DEFAULT_CHROOT); cfgUnloadConfig(&cfg); } else { Timeout = atoi(DEFAULT_TIMEOUT); AIT_SET_STR(&User, DEFAULT_USER); AIT_SET_STR(&Mount, DEFAULT_MOUNT); AIT_SET_STR(&Dev, DEFAULT_DEVICE); AIT_SET_STR(&Chroot, DEFAULT_CHROOT); } atexit(cleanexit); /* Load variables from arguments if exists */ while ((ch = getopt(argc, argv, "hvu:c:d:m:t:")) != -1) switch (ch) { case 'v': Verbose++; break; case 'u': AIT_SET_STR(&User, optarg); break; case 'c': AIT_SET_STR(&Chroot, optarg); break; case 'd': AIT_SET_STR(&Dev, optarg); break; case 'm': AIT_SET_STR(&Mount, optarg); break; case 't': #ifndef HAVE_STRTONUM Timeout = (int) strtol(optarg, NULL, 0); #else Timeout = strtonum(optarg, 0, 3600, &err); #endif if (!Timeout && err) { printf("Error:: in seconds for timeout %s - %s\n", optarg, err); return 1; } break; case 'h': default: Usage(); return 1; } argc -= optind; argv += optind; memset(szSess, 0, MAXPATHLEN); snprintf(szSess, MAXPATHLEN, "%s%s-cfexec.LCK", DEFAULT_TMP, AIT_GET_STR(&Mount)); VERB(3) printf("Info(3):: Chroot=%s SUID=%s Device=%s Mount=%s Timeout=%d Session=%s\n", AIT_GET_STR(&Chroot), AIT_GET_STR(&User), AIT_GET_STR(&Dev), AIT_GET_STR(&Mount), Timeout, szSess); if (!access(szSess, F_OK)) { printf("cfexec already running ...\n"); return 127; } if (!argc) { switch (fork()) { case -1: printf("Error:: can`t execute safe mount #%d - %s\n", errno, strerror(errno)); return 3; case 0: VERB(5) printf("Info(5):: Go safe mount.\n"); setsid(); if (update(MNT_UPDATE) == -1) return 4; if ((f = mkevent(&chg, &evt)) == -1) return 5; if (Timeout) { memset(&ts, 0, sizeof ts); ts.tv_sec = Timeout; } switch (kevent(kq, &chg, 1, &evt, 1, !Timeout ? NULL : &ts)) { case -1: printf("Error:: can`t execute safe mount #%d - %s\n", errno, strerror(errno)); stat = 7; break; case 0: VERB(1) printf("Timeout reached - secure mount\n"); default: VERB(1) printf("Lock file is deleted - secure mount\n"); if (update(MNT_UPDATE | MNT_RDONLY) == -1) stat = 8; } close(kq); close(f); unlink(szSess); break; } } else { /* sigemptyset(&sig); sigaddset(&sig, SIGINT); sigaddset(&sig, SIGTSTP); sigprocmask(SIG_BLOCK, &sig, &oldsig); */ if (update(MNT_UPDATE) == -1) return 4; switch ((pid = vfork())) { case -1: printf("Error:: can`t execute safe mount #%d - %s\n", errno, strerror(errno)); return 5; case 0: VERB(5) printf("Go to running process %s\n", *argv); if (chroot(AIT_GET_STR(&Chroot)) == -1) { printf("Error:: can`t chroot to dir %s #%d - %s\n", AIT_GET_STR(&Chroot), errno, strerror(errno)); } else { if (strncmp(AIT_GET_STR(&User), "root", 5)) setuser(); /* chdir("/"); */ execvp(*argv, argv); } exit(127); break; default: waitpid(pid, &stat, 0); VERB(3) printf("Return code: %d\n", stat); if (stat == 32512) stat = 127; if (update(MNT_UPDATE | MNT_RDONLY) == -1) return 8; } } return stat; }