int virtTestCaptureProgramOutput(const char *const argv[], char **buf, int maxlen) { int pipefd[2]; int len; if (pipe(pipefd) < 0) return -1; pid_t pid = fork(); switch (pid) { case 0: VIR_FORCE_CLOSE(pipefd[0]); virtTestCaptureProgramExecChild(argv, pipefd[1]); VIR_FORCE_CLOSE(pipefd[1]); _exit(1); case -1: return -1; default: VIR_FORCE_CLOSE(pipefd[1]); len = virFileReadLimFD(pipefd[0], maxlen, buf); VIR_FORCE_CLOSE(pipefd[0]); if (virProcessWait(pid, NULL) < 0) return -1; return len; } }
static int daemonForkIntoBackground(const char *argv0) { int statuspipe[2]; if (pipe(statuspipe) < 0) return -1; pid_t pid = fork(); switch (pid) { case 0: { /* intermediate child */ int stdinfd = -1; int stdoutfd = -1; int nextpid; VIR_FORCE_CLOSE(statuspipe[0]); if ((stdinfd = open("/dev/null", O_RDONLY)) < 0) goto cleanup; if ((stdoutfd = open("/dev/null", O_WRONLY)) < 0) goto cleanup; if (dup2(stdinfd, STDIN_FILENO) != STDIN_FILENO) goto cleanup; if (dup2(stdoutfd, STDOUT_FILENO) != STDOUT_FILENO) goto cleanup; if (dup2(stdoutfd, STDERR_FILENO) != STDERR_FILENO) goto cleanup; if (stdinfd > STDERR_FILENO && VIR_CLOSE(stdinfd) < 0) goto cleanup; if (stdoutfd > STDERR_FILENO && VIR_CLOSE(stdoutfd) < 0) goto cleanup; if (setsid() < 0) goto cleanup; nextpid = fork(); switch (nextpid) { case 0: /* grandchild */ return statuspipe[1]; case -1: /* error */ goto cleanup; default: /* intermediate child succeeded */ _exit(EXIT_SUCCESS); } cleanup: VIR_FORCE_CLOSE(stdoutfd); VIR_FORCE_CLOSE(stdinfd); VIR_FORCE_CLOSE(statuspipe[1]); _exit(EXIT_FAILURE); } case -1: /* error in parent */ goto error; default: { /* parent */ int ret; char status; VIR_FORCE_CLOSE(statuspipe[1]); /* We wait to make sure the first child forked successfully */ if (virProcessWait(pid, NULL, false) < 0) goto error; /* If we get here, then the grandchild was spawned, so we * must exit. Block until the second child initializes * successfully */ again: ret = read(statuspipe[0], &status, 1); if (ret == -1 && errno == EINTR) goto again; VIR_FORCE_CLOSE(statuspipe[0]); if (ret != 1) { char ebuf[1024]; fprintf(stderr, _("%s: error: unable to determine if daemon is " "running: %s\n"), argv0, virStrerror(errno, ebuf, sizeof(ebuf))); exit(EXIT_FAILURE); } else if (status != 0) { fprintf(stderr, _("%s: error: %s. Check /var/log/messages or run " "without --daemon for more info.\n"), argv0, virDaemonErrTypeToString(status)); exit(EXIT_FAILURE); } _exit(EXIT_SUCCESS); } } error: VIR_FORCE_CLOSE(statuspipe[0]); VIR_FORCE_CLOSE(statuspipe[1]); return -1; }
int main(int argc, char **argv) { virConfPtr conf = NULL; const char *login_shell_path = conf_file; pid_t cpid = -1; int ret = EXIT_CANCELED; int status; uid_t uid = getuid(); gid_t gid = getgid(); char *name = NULL; char **shargv = NULL; virSecurityModelPtr secmodel = NULL; virSecurityLabelPtr seclabel = NULL; virDomainPtr dom = NULL; virConnectPtr conn = NULL; char *homedir = NULL; int arg; int longindex = -1; int ngroups; gid_t *groups = NULL; ssize_t nfdlist = 0; int *fdlist = NULL; int openmax; size_t i; struct option opt[] = { {"help", no_argument, NULL, 'h'}, {"version", optional_argument, NULL, 'V'}, {NULL, 0, NULL, 0} }; if (virInitialize() < 0) { fprintf(stderr, _("Failed to initialize libvirt error handling")); return EXIT_CANCELED; } setenv("PATH", "/bin:/usr/bin", 1); virSetErrorFunc(NULL, NULL); virSetErrorLogPriorityFunc(NULL); progname = argv[0]; if (!setlocale(LC_ALL, "")) { perror("setlocale"); /* failure to setup locale is not fatal */ } if (!bindtextdomain(PACKAGE, LOCALEDIR)) { perror("bindtextdomain"); return ret; } if (!textdomain(PACKAGE)) { perror("textdomain"); return ret; } while ((arg = getopt_long(argc, argv, "hV", opt, &longindex)) != -1) { switch (arg) { case 'h': usage(); exit(EXIT_SUCCESS); case 'V': show_version(); exit(EXIT_SUCCESS); case '?': default: usage(); exit(EXIT_CANCELED); } } if (argc > optind) { virReportSystemError(EINVAL, _("%s takes no options"), progname); goto cleanup; } if (uid == 0) { virReportSystemError(EPERM, _("%s must be run by non root users"), progname); goto cleanup; } name = virGetUserName(uid); if (!name) goto cleanup; homedir = virGetUserDirectoryByUID(uid); if (!homedir) goto cleanup; if (!(conf = virConfReadFile(login_shell_path, 0))) goto cleanup; if ((ngroups = virGetGroupList(uid, gid, &groups)) < 0) goto cleanup; if (virLoginShellAllowedUser(conf, name, groups) < 0) goto cleanup; if (!(shargv = virLoginShellGetShellArgv(conf))) goto cleanup; conn = virConnectOpen("lxc:///"); if (!conn) goto cleanup; dom = virDomainLookupByName(conn, name); if (!dom) goto cleanup; if (!virDomainIsActive(dom) && virDomainCreate(dom)) { virErrorPtr last_error; last_error = virGetLastError(); if (last_error->code != VIR_ERR_OPERATION_INVALID) { virReportSystemError(last_error->code, _("Can't create %s container: %s"), name, last_error->message); goto cleanup; } } openmax = sysconf(_SC_OPEN_MAX); if (openmax < 0) { virReportSystemError(errno, "%s", _("sysconf(_SC_OPEN_MAX) failed")); goto cleanup; } if ((nfdlist = virDomainLxcOpenNamespace(dom, &fdlist, 0)) < 0) goto cleanup; if (VIR_ALLOC(secmodel) < 0) goto cleanup; if (VIR_ALLOC(seclabel) < 0) goto cleanup; if (virNodeGetSecurityModel(conn, secmodel) < 0) goto cleanup; if (virDomainGetSecurityLabel(dom, seclabel) < 0) goto cleanup; if (virSetUIDGID(0, 0, NULL, 0) < 0) goto cleanup; if (virDomainLxcEnterSecurityLabel(secmodel, seclabel, NULL, 0) < 0) goto cleanup; if (nfdlist > 0 && virDomainLxcEnterNamespace(dom, nfdlist, fdlist, NULL, NULL, 0) < 0) goto cleanup; if (virSetUIDGID(uid, gid, groups, ngroups) < 0) goto cleanup; if (chdir(homedir) < 0) { virReportSystemError(errno, _("Unable to chdir(%s)"), homedir); goto cleanup; } /* A fork is required to create new process in correct pid namespace. */ if ((cpid = virFork()) < 0) goto cleanup; if (cpid == 0) { int tmpfd; for (i = 3; i < openmax; i++) { tmpfd = i; VIR_MASS_CLOSE(tmpfd); } if (execv(shargv[0], (char *const*) shargv) < 0) { virReportSystemError(errno, _("Unable to exec shell %s"), shargv[0]); virDispatchError(NULL); return errno == ENOENT ? EXIT_ENOENT : EXIT_CANNOT_INVOKE; } } /* At this point, the parent is now waiting for the child to exit, * but as that may take a long time, we release resources now. */ cleanup: if (nfdlist > 0) for (i = 0; i < nfdlist; i++) VIR_FORCE_CLOSE(fdlist[i]); VIR_FREE(fdlist); virConfFree(conf); if (dom) virDomainFree(dom); if (conn) virConnectClose(conn); virStringFreeList(shargv); VIR_FREE(name); VIR_FREE(homedir); VIR_FREE(seclabel); VIR_FREE(secmodel); VIR_FREE(groups); if (virProcessWait(cpid, &status, true) == 0) virProcessExitWithStatus(status); if (virGetLastError()) virDispatchError(NULL); return ret; }