#include "qemu/osdep.h"
#include <sys/wait.h>
-/*needed for MAP_POPULATE before including qemu-options.h */
-#include <sys/mman.h>
#include <pwd.h>
#include <grp.h>
#include <libgen.h>
+#include "qemu-common.h"
/* Needed early for CONFIG_BSD etc. */
-#include "sysemu/sysemu.h"
#include "net/slirp.h"
#include "qemu-options.h"
-#include "qemu/rcu.h"
#include "qemu/error-report.h"
#include "qemu/log.h"
+#include "sysemu/runstate.h"
+#include "qemu/cutils.h"
#ifdef CONFIG_LINUX
#include <sys/prctl.h>
#endif
-static struct passwd *user_pwd;
+/*
+ * 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;
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"
+/*
+ * Find a likely location for support files using the location of the binary.
+ * When running from the build tree this will be "$bindir/../pc-bios".
+ * Otherwise, this is CONFIG_QEMU_DATADIR.
+ */
char *os_find_datadir(void)
{
- char *dir, *exec_dir;
- char *res;
- size_t max_len;
+ g_autofree char *exec_dir = NULL;
+ g_autofree char *dir = NULL;
exec_dir = qemu_get_exec_dir();
- if (exec_dir == NULL) {
- return NULL;
- }
- dir = 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_return_val_if_fail(exec_dir != NULL, NULL);
+
+ dir = g_build_filename(exec_dir, "..", "pc-bios", NULL);
+ if (g_file_test(dir, G_FILE_TEST_IS_DIR)) {
+ return g_steal_pointer(&dir);
}
- g_free(exec_dir);
- return res;
+ return g_strdup(CONFIG_QEMU_DATADIR);
}
-#undef SHARE_SUFFIX
-#undef BUILD_SUFFIX
void os_set_proc_name(const char *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)) {
- perror("unable to change process name");
+ error_report("unable to change process name: %s", strerror(errno));
exit(1);
}
#else
- fprintf(stderr, "Change of process name not supported by your OS\n");
+ 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
*/
-void os_parse_cmd_args(int index, const char *optarg)
+int os_parse_cmd_args(int index, const char *optarg)
{
switch (index) {
-#ifdef CONFIG_SLIRP
- case QEMU_OPTION_smb:
- error_report("The -smb option is deprecated. "
- "Please use '-netdev user,smb=...' instead.");
- if (net_slirp_smb(optarg) < 0)
- exit(1);
- break;
-#endif
case QEMU_OPTION_runas:
user_pwd = getpwnam(optarg);
- if (!user_pwd) {
- fprintf(stderr, "User \"%s\" doesn't exist\n", 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;
fips_set_state(true);
break;
#endif
+ default:
+ return -1;
}
+
+ return 0;
}
static void change_process_uid(void)
{
- if (user_pwd) {
- if (setgid(user_pwd->pw_gid) < 0) {
- fprintf(stderr, "Failed to setgid(%d)\n", user_pwd->pw_gid);
+ 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 (initgroups(user_pwd->pw_name, user_pwd->pw_gid) < 0) {
- fprintf(stderr, "Failed to initgroups(\"%s\", %d)\n",
- user_pwd->pw_name, user_pwd->pw_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(user_pwd->pw_uid) < 0) {
- fprintf(stderr, "Failed to setuid(%d)\n", user_pwd->pw_uid);
+ if (setuid(intended_uid) < 0) {
+ error_report("Failed to setuid(%d)", intended_uid);
exit(1);
}
if (setuid(0) != -1) {
- fprintf(stderr, "Dropping privileges failed\n");
+ error_report("Dropping privileges failed");
exit(1);
}
}
{
if (chroot_dir) {
if (chroot(chroot_dir) < 0) {
- fprintf(stderr, "chroot failed\n");
+ error_report("chroot failed");
exit(1);
}
if (chdir("/")) {
- perror("not able to chdir to /");
+ error_report("not able to chdir to /: %s", strerror(errno));
exit(1);
}
}
signal(SIGTSTP, SIG_IGN);
signal(SIGTTOU, SIG_IGN);
signal(SIGTTIN, SIG_IGN);
- rcu_after_fork();
}
}
if (daemonize) {
if (chdir("/")) {
- perror("not able to chdir to /");
+ error_report("not able to chdir to /: %s", strerror(errno));
exit(1);
}
TFR(fd = qemu_open("/dev/null", O_RDWR));
setvbuf(stdout, NULL, _IOLBF, 0);
}
-int qemu_create_pidfile(const char *filename)
-{
- char buffer[128];
- int len;
- int fd;
-
- fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
- if (fd == -1) {
- return -1;
- }
- if (lockf(fd, F_TLOCK, 0) == -1) {
- close(fd);
- return -1;
- }
- len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", getpid());
- if (write(fd, buffer, len) != len) {
- close(fd);
- return -1;
- }
-
- /* keep pidfile open & locked forever */
- return 0;
-}
-
bool is_daemonized(void)
{
return daemonize;
ret = mlockall(MCL_CURRENT | MCL_FUTURE);
if (ret < 0) {
- perror("mlockall");
+ error_report("mlockall: %s", strerror(errno));
}
return ret;