* THE SOFTWARE.
*/
-#include <unistd.h>
-#include <fcntl.h>
-#include <signal.h>
+#include "qemu/osdep.h"
+#include <sys/wait.h>
+#include <pwd.h>
+#include <grp.h>
+#include <libgen.h>
/* Needed early for CONFIG_BSD etc. */
-#include "config-host.h"
-#include "sysemu.h"
+#include "sysemu/sysemu.h"
+#include "net/slirp.h"
+#include "qemu-options.h"
+#include "qemu/error-report.h"
+#include "qemu/log.h"
+#include "qemu/cutils.h"
-void os_setup_signal_handling(void)
+#ifdef CONFIG_LINUX
+#include <sys/prctl.h>
+#endif
+
+/*
+ * Must set all three of these at once.
+ * Legal combinations are unset by name by uid
+ */
+static struct passwd *user_pwd; /* NULL non-NULL NULL */
+static uid_t user_uid = (uid_t)-1; /* -1 -1 >=0 */
+static gid_t user_gid = (gid_t)-1; /* -1 -1 >=0 */
+
+static const char *chroot_dir;
+static int daemonize;
+static int daemon_pipe;
+
+void os_setup_early_signal_handling(void)
{
struct sigaction act;
sigfillset(&act.sa_mask);
act.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &act, NULL);
}
+
+static void termsig_handler(int signal, siginfo_t *info, void *c)
+{
+ qemu_system_killed(info->si_signo, info->si_pid);
+}
+
+void os_setup_signal_handling(void)
+{
+ struct sigaction act;
+
+ memset(&act, 0, sizeof(act));
+ act.sa_sigaction = termsig_handler;
+ act.sa_flags = SA_SIGINFO;
+ sigaction(SIGINT, &act, NULL);
+ sigaction(SIGHUP, &act, NULL);
+ sigaction(SIGTERM, &act, NULL);
+}
+
+/* Find a likely location for support files using the location of the binary.
+ For installed binaries this will be "$bindir/../share/qemu". When
+ running from the build tree this will be "$bindir/../pc-bios". */
+#define SHARE_SUFFIX "/share/qemu"
+#define BUILD_SUFFIX "/pc-bios"
+char *os_find_datadir(void)
+{
+ char *dir, *exec_dir;
+ char *res;
+ size_t max_len;
+
+ exec_dir = qemu_get_exec_dir();
+ if (exec_dir == NULL) {
+ return NULL;
+ }
+ dir = g_path_get_dirname(exec_dir);
+
+ max_len = strlen(dir) +
+ MAX(strlen(SHARE_SUFFIX), strlen(BUILD_SUFFIX)) + 1;
+ res = g_malloc0(max_len);
+ snprintf(res, max_len, "%s%s", dir, SHARE_SUFFIX);
+ if (access(res, R_OK)) {
+ snprintf(res, max_len, "%s%s", dir, BUILD_SUFFIX);
+ if (access(res, R_OK)) {
+ g_free(res);
+ res = NULL;
+ }
+ }
+
+ g_free(dir);
+ g_free(exec_dir);
+ return res;
+}
+#undef SHARE_SUFFIX
+#undef BUILD_SUFFIX
+
+void os_set_proc_name(const char *s)
+{
+#if defined(PR_SET_NAME)
+ char name[16];
+ if (!s)
+ return;
+ pstrcpy(name, sizeof(name), s);
+ /* Could rewrite argv[0] too, but that's a bit more complicated.
+ This simple way is enough for `top'. */
+ if (prctl(PR_SET_NAME, name)) {
+ error_report("unable to change process name: %s", strerror(errno));
+ exit(1);
+ }
+#else
+ error_report("Change of process name not supported by your OS");
+ exit(1);
+#endif
+}
+
+
+static bool os_parse_runas_uid_gid(const char *optarg)
+{
+ unsigned long lv;
+ const char *ep;
+ uid_t got_uid;
+ gid_t got_gid;
+ int rc;
+
+ rc = qemu_strtoul(optarg, &ep, 0, &lv);
+ got_uid = lv; /* overflow here is ID in C99 */
+ if (rc || *ep != ':' || got_uid != lv || got_uid == (uid_t)-1) {
+ return false;
+ }
+
+ rc = qemu_strtoul(ep + 1, 0, 0, &lv);
+ got_gid = lv; /* overflow here is ID in C99 */
+ if (rc || got_gid != lv || got_gid == (gid_t)-1) {
+ return false;
+ }
+
+ user_pwd = NULL;
+ user_uid = got_uid;
+ user_gid = got_gid;
+ return true;
+}
+
+/*
+ * Parse OS specific command line options.
+ * return 0 if option handled, -1 otherwise
+ */
+int os_parse_cmd_args(int index, const char *optarg)
+{
+ switch (index) {
+ case QEMU_OPTION_runas:
+ user_pwd = getpwnam(optarg);
+ if (user_pwd) {
+ user_uid = -1;
+ user_gid = -1;
+ } else if (!os_parse_runas_uid_gid(optarg)) {
+ error_report("User \"%s\" doesn't exist"
+ " (and is not <uid>:<gid>)",
+ optarg);
+ exit(1);
+ }
+ break;
+ case QEMU_OPTION_chroot:
+ chroot_dir = optarg;
+ break;
+ case QEMU_OPTION_daemonize:
+ daemonize = 1;
+ break;
+#if defined(CONFIG_LINUX)
+ case QEMU_OPTION_enablefips:
+ fips_set_state(true);
+ break;
+#endif
+ default:
+ return -1;
+ }
+
+ return 0;
+}
+
+static void change_process_uid(void)
+{
+ assert((user_uid == (uid_t)-1) || user_pwd == NULL);
+ assert((user_uid == (uid_t)-1) ==
+ (user_gid == (gid_t)-1));
+
+ if (user_pwd || user_uid != (uid_t)-1) {
+ gid_t intended_gid = user_pwd ? user_pwd->pw_gid : user_gid;
+ uid_t intended_uid = user_pwd ? user_pwd->pw_uid : user_uid;
+ if (setgid(intended_gid) < 0) {
+ error_report("Failed to setgid(%d)", intended_gid);
+ exit(1);
+ }
+ if (user_pwd) {
+ if (initgroups(user_pwd->pw_name, user_pwd->pw_gid) < 0) {
+ error_report("Failed to initgroups(\"%s\", %d)",
+ user_pwd->pw_name, user_pwd->pw_gid);
+ exit(1);
+ }
+ } else {
+ if (setgroups(1, &user_gid) < 0) {
+ error_report("Failed to setgroups(1, [%d])",
+ user_gid);
+ exit(1);
+ }
+ }
+ if (setuid(intended_uid) < 0) {
+ error_report("Failed to setuid(%d)", intended_uid);
+ exit(1);
+ }
+ if (setuid(0) != -1) {
+ error_report("Dropping privileges failed");
+ exit(1);
+ }
+ }
+}
+
+static void change_root(void)
+{
+ if (chroot_dir) {
+ if (chroot(chroot_dir) < 0) {
+ error_report("chroot failed");
+ exit(1);
+ }
+ if (chdir("/")) {
+ error_report("not able to chdir to /: %s", strerror(errno));
+ exit(1);
+ }
+ }
+
+}
+
+void os_daemonize(void)
+{
+ if (daemonize) {
+ pid_t pid;
+ int fds[2];
+
+ if (pipe(fds) == -1) {
+ exit(1);
+ }
+
+ pid = fork();
+ if (pid > 0) {
+ uint8_t status;
+ ssize_t len;
+
+ close(fds[1]);
+
+ do {
+ len = read(fds[0], &status, 1);
+ } while (len < 0 && errno == EINTR);
+
+ /* only exit successfully if our child actually wrote
+ * a one-byte zero to our pipe, upon successful init */
+ exit(len == 1 && status == 0 ? 0 : 1);
+
+ } else if (pid < 0) {
+ exit(1);
+ }
+
+ close(fds[0]);
+ daemon_pipe = fds[1];
+ qemu_set_cloexec(daemon_pipe);
+
+ setsid();
+
+ pid = fork();
+ if (pid > 0) {
+ exit(0);
+ } else if (pid < 0) {
+ exit(1);
+ }
+ umask(027);
+
+ signal(SIGTSTP, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ signal(SIGTTIN, SIG_IGN);
+ }
+}
+
+void os_setup_post(void)
+{
+ int fd = 0;
+
+ if (daemonize) {
+ if (chdir("/")) {
+ error_report("not able to chdir to /: %s", strerror(errno));
+ exit(1);
+ }
+ TFR(fd = qemu_open("/dev/null", O_RDWR));
+ if (fd == -1) {
+ exit(1);
+ }
+ }
+
+ change_root();
+ change_process_uid();
+
+ if (daemonize) {
+ uint8_t status = 0;
+ ssize_t len;
+
+ dup2(fd, 0);
+ dup2(fd, 1);
+ /* In case -D is given do not redirect stderr to /dev/null */
+ if (!qemu_logfile) {
+ dup2(fd, 2);
+ }
+
+ close(fd);
+
+ do {
+ len = write(daemon_pipe, &status, 1);
+ } while (len < 0 && errno == EINTR);
+ if (len != 1) {
+ exit(1);
+ }
+ }
+}
+
+void os_set_line_buffering(void)
+{
+ setvbuf(stdout, NULL, _IOLBF, 0);
+}
+
+bool is_daemonized(void)
+{
+ return daemonize;
+}
+
+int os_mlock(void)
+{
+ int ret = 0;
+
+ ret = mlockall(MCL_CURRENT | MCL_FUTURE);
+ if (ret < 0) {
+ error_report("mlockall: %s", strerror(errno));
+ }
+
+ return ret;
+}
projects / mirror_qemu.git / blobdiff