X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=os-posix.c;h=804e20c189454ce09155fee99d645cd21b72d920;hb=03c71553ad735068e2bf166e629026fc78dbb4b9;hp=621ad062b0fd40ab958614fd5ed621767124141a;hpb=6170540b824635a29eb7a0360affac9394c84c52;p=qemu.git

diff --git a/os-posix.c b/os-posix.c
index 621ad062b..804e20c18 100644
--- a/os-posix.c
+++ b/os-posix.c
@@ -28,11 +28,23 @@
 #include <signal.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <pwd.h>
 #include <libgen.h>
 
 /* Needed early for CONFIG_BSD etc. */
 #include "config-host.h"
 #include "sysemu.h"
+#include "net/slirp.h"
+#include "qemu-options.h"
+
+#ifdef CONFIG_LINUX
+#include <sys/prctl.h>
+#endif
+
+static struct passwd *user_pwd;
+static const char *chroot_dir;
+static int daemonize;
+static int fds[2];
 
 void os_setup_early_signal_handling(void)
 {
@@ -130,3 +142,188 @@ char *os_find_datadir(const char *argv0)
 }
 #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;
+    name[sizeof(name) - 1] = 0;
+    strncpy(name, s, sizeof(name));
+    /* 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");
+        exit(1);
+    }
+#else
+    fprintf(stderr, "Change of process name not supported by your OS\n");
+    exit(1);
+#endif
+}
+
+/*
+ * Parse OS specific command line options.
+ * return 0 if option handled, -1 otherwise
+ */
+void os_parse_cmd_args(int index, const char *optarg)
+{
+    switch (index) {
+#ifdef CONFIG_SLIRP
+    case QEMU_OPTION_smb:
+        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);
+            exit(1);
+        }
+        break;
+    case QEMU_OPTION_chroot:
+        chroot_dir = optarg;
+        break;
+    case QEMU_OPTION_daemonize:
+        daemonize = 1;
+        break;
+    }
+    return;
+}
+
+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);
+            exit(1);
+        }
+        if (setuid(user_pwd->pw_uid) < 0) {
+            fprintf(stderr, "Failed to setuid(%d)\n", user_pwd->pw_uid);
+            exit(1);
+        }
+        if (setuid(0) != -1) {
+            fprintf(stderr, "Dropping privileges failed\n");
+            exit(1);
+        }
+    }
+}
+
+static void change_root(void)
+{
+    if (chroot_dir) {
+        if (chroot(chroot_dir) < 0) {
+            fprintf(stderr, "chroot failed\n");
+            exit(1);
+        }
+        if (chdir("/")) {
+            perror("not able to chdir to /");
+            exit(1);
+        }
+    }
+
+}
+
+void os_daemonize(void)
+{
+    if (daemonize) {
+	pid_t pid;
+
+	if (pipe(fds) == -1)
+	    exit(1);
+
+	pid = fork();
+	if (pid > 0) {
+	    uint8_t status;
+	    ssize_t len;
+
+	    close(fds[1]);
+
+	again:
+            len = read(fds[0], &status, 1);
+            if (len == -1 && (errno == EINTR))
+                goto again;
+
+            if (len != 1)
+                exit(1);
+            else if (status == 1) {
+                fprintf(stderr, "Could not acquire pidfile: %s\n", strerror(errno));
+                exit(1);
+            } else
+                exit(0);
+	} else if (pid < 0)
+            exit(1);
+
+	close(fds[0]);
+	qemu_set_cloexec(fds[1]);
+
+	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) {
+	uint8_t status = 0;
+	ssize_t len;
+
+    again1:
+	len = write(fds[1], &status, 1);
+	if (len == -1 && (errno == EINTR))
+	    goto again1;
+
+	if (len != 1)
+	    exit(1);
+
+        if (chdir("/")) {
+            perror("not able to chdir to /");
+            exit(1);
+        }
+	TFR(fd = qemu_open("/dev/null", O_RDWR));
+	if (fd == -1)
+	    exit(1);
+    }
+
+    change_root();
+    change_process_uid();
+
+    if (daemonize) {
+        dup2(fd, 0);
+        dup2(fd, 1);
+        dup2(fd, 2);
+
+        close(fd);
+    }
+}
+
+void os_pidfile_error(void)
+{
+    if (daemonize) {
+        uint8_t status = 1;
+        if (write(fds[1], &status, 1) != 1) {
+            perror("daemonize. Writing to pipe\n");
+        }
+    } else
+        fprintf(stderr, "Could not acquire pid file: %s\n", strerror(errno));
+}
+
+void os_set_line_buffering(void)
+{
+    setvbuf(stdout, NULL, _IOLBF, 0);
+}