/* libguestfs
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009-2010 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
#include <stdlib.h>
#include <stdarg.h>
#include <stddef.h>
+#include <stdint.h>
+#include <inttypes.h>
#include <unistd.h>
-#include <ctype.h>
#include <string.h>
#include <fcntl.h>
#include <time.h>
#include <sys/stat.h>
#include <sys/select.h>
#include <dirent.h>
+#include <signal.h>
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <sys/un.h>
#endif
+#include <arpa/inet.h>
+#include <netinet/in.h>
+
+#include "c-ctype.h"
+#include "glthread/lock.h"
+#include "ignore-value.h"
+
#include "guestfs.h"
+#include "guestfs-internal.h"
#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
-#include "ignore-value.h"
#ifdef HAVE_GETTEXT
#include "gettext.h"
#define safe_strdup guestfs_safe_strdup
//#define safe_memdup guestfs_safe_memdup
+#ifdef __linux__
+#define CAN_CHECK_PEER_EUID 1
+#else
+#define CAN_CHECK_PEER_EUID 0
+#endif
+
static void default_error_cb (guestfs_h *g, void *data, const char *msg);
static int send_to_daemon (guestfs_h *g, const void *v_buf, size_t n);
static int recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn);
+static int accept_from_daemon (guestfs_h *g);
+static int check_peer_euid (guestfs_h *g, int sock, uid_t *rtn);
static void close_handles (void);
+static int qemu_supports (guestfs_h *g, const char *option);
#define UNIX_PATH_MAX 108
-/* Also in guestfsd.c */
-#define GUESTFWD_PORT 6666
+#ifndef MAX
+#define MAX(a,b) ((a)>(b)?(a):(b))
+#endif
+
+#ifdef __APPLE__
+#define xdr_uint32_t xdr_u_int32_t
+#endif
+
+/* Network configuration of the appliance. Note these addresses are
+ * only meaningful within the context of the running appliance. QEMU
+ * translates network connections to these magic addresses into
+ * userspace calls on the host (eg. connect(2)). qemu-doc has a nice
+ * diagram which is also useful to refer to.
+ *
+ * NETWORK: The network.
+ *
+ * ROUTER: The address of the "host", ie. this library.
+ *
+ * [Note: If you change NETWORK and ROUTER then you also have to
+ * change the network configuration in appliance/init].
+ *
+ * GUESTFWD_ADDR, GUESTFWD_PORT: The guestfwd feature of qemu
+ * magically connects this pseudo-address to the guestfwd channel. In
+ * typical Linux configurations of libguestfs, guestfwd is not
+ * actually used any more.
+ */
+#define NETWORK "10.0.2.0/8"
+#define ROUTER "10.0.2.2"
#define GUESTFWD_ADDR "10.0.2.4"
+#define GUESTFWD_PORT "6666"
/* GuestFS handle and connection. */
enum state { CONFIG, LAUNCHING, READY, BUSY, NO_HANDLE };
int sock; /* Daemon communications socket. */
pid_t pid; /* Qemu PID. */
pid_t recoverypid; /* Recovery process PID. */
- time_t start_t; /* The time when we started qemu. */
+
+ struct timeval launch_t; /* The time that we called guestfs_launch. */
char *tmpdir; /* Temporary directory containing socket. */
int verbose;
int trace;
int autosync;
+ int direct;
+ int recovery_proc;
char *path; /* Path to kernel, initrd. */
char *qemu; /* Qemu binary. */
int msg_next_serial;
};
+gl_lock_define_initialized (static, handles_lock);
static guestfs_h *handles = NULL;
static int atexit_handler_set = 0;
g->error_cb = default_error_cb;
g->error_cb_data = NULL;
+ g->recovery_proc = 1;
+
str = getenv ("LIBGUESTFS_DEBUG");
- g->verbose = str != NULL && strcmp (str, "1") == 0;
+ g->verbose = str != NULL && STREQ (str, "1");
str = getenv ("LIBGUESTFS_TRACE");
- g->trace = str != NULL && strcmp (str, "1") == 0;
+ g->trace = str != NULL && STREQ (str, "1");
str = getenv ("LIBGUESTFS_PATH");
g->path = str != NULL ? strdup (str) : strdup (GUESTFS_DEFAULT_PATH);
*/
g->msg_next_serial = 0x00123400;
- /* Link the handles onto a global list. This is the one area
- * where the library needs to be made thread-safe. (XXX)
- */
- /* acquire mutex (XXX) */
+ /* Link the handles onto a global list. */
+ gl_lock_lock (handles_lock);
g->next = handles;
handles = g;
if (!atexit_handler_set) {
atexit (close_handles);
atexit_handler_set = 1;
}
- /* release mutex (XXX) */
+ gl_lock_unlock (handles_lock);
if (g->verbose)
fprintf (stderr, "new guestfs handle %p\n", g);
/* Mark the handle as dead before freeing it. */
g->state = NO_HANDLE;
- /* acquire mutex (XXX) */
+ gl_lock_lock (handles_lock);
if (handles == g)
handles = g->next;
else {
;
gg->next = g->next;
}
- /* release mutex (XXX) */
+ gl_lock_unlock (handles_lock);
free (g->last_error);
free (g->path);
if (err < 0) return;
-#ifndef _GNU_SOURCE
+#if !defined(_GNU_SOURCE) || defined(__APPLE__)
char buf[256];
strerror_r (errnum, buf, sizeof buf);
#else
/* Technically we should add an autoconf test for this, testing for the desired
functionality, like what's done in gnulib, but for now, this is fine. */
+#if defined(__GLIBC__)
#define HAVE_GNU_CALLOC (__GLIBC__ >= 2)
+#else
+#define HAVE_GNU_CALLOC 0
+#endif
/* Allocate zeroed memory for N elements of S bytes, with error
checking. S must be nonzero. */
return g->trace;
}
+int
+guestfs__set_direct (guestfs_h *g, int d)
+{
+ g->direct = !!d;
+ return 0;
+}
+
+int
+guestfs__get_direct (guestfs_h *g)
+{
+ return g->direct;
+}
+
+int
+guestfs__set_recovery_proc (guestfs_h *g, int f)
+{
+ g->recovery_proc = !!f;
+ return 0;
+}
+
+int
+guestfs__get_recovery_proc (guestfs_h *g)
+{
+ return g->recovery_proc;
+}
+
/* Add a string to the current command line. */
static void
incr_cmdline_size (guestfs_h *g)
/* A bit fascist, but the user will probably break the extra
* parameters that we add if they try to set any of these.
*/
- if (strcmp (qemu_param, "-kernel") == 0 ||
- strcmp (qemu_param, "-initrd") == 0 ||
- strcmp (qemu_param, "-nographic") == 0 ||
- strcmp (qemu_param, "-serial") == 0 ||
- strcmp (qemu_param, "-full-screen") == 0 ||
- strcmp (qemu_param, "-std-vga") == 0 ||
- strcmp (qemu_param, "-vnc") == 0) {
+ if (STREQ (qemu_param, "-kernel") ||
+ STREQ (qemu_param, "-initrd") ||
+ STREQ (qemu_param, "-nographic") ||
+ STREQ (qemu_param, "-serial") ||
+ STREQ (qemu_param, "-full-screen") ||
+ STREQ (qemu_param, "-std-vga") ||
+ STREQ (qemu_param, "-vnc")) {
error (g, _("guestfs_config: parameter '%s' isn't allowed"), qemu_param);
return -1;
}
}
int
-guestfs__add_drive (guestfs_h *g, const char *filename)
+guestfs__add_drive_with_if (guestfs_h *g, const char *filename,
+ const char *drive_if)
{
size_t len = strlen (filename) + 64;
char buf[len];
int fd = open (filename, O_RDONLY|O_DIRECT);
if (fd >= 0) {
close (fd);
- snprintf (buf, len, "file=%s,cache=off,if=" DRIVE_IF, filename);
+ snprintf (buf, len, "file=%s,cache=off,if=%s", filename, drive_if);
} else {
fd = open (filename, O_RDONLY);
if (fd >= 0) {
close (fd);
- snprintf (buf, len, "file=%s,if=" DRIVE_IF, filename);
+ snprintf (buf, len, "file=%s,if=%s", filename, drive_if);
} else {
perrorf (g, "%s", filename);
return -1;
}
int
-guestfs__add_drive_ro (guestfs_h *g, const char *filename)
+guestfs__add_drive_ro_with_if (guestfs_h *g, const char *filename,
+ const char *drive_if)
{
- size_t len = strlen (filename) + 64;
- char buf[len];
-
if (strchr (filename, ',') != NULL) {
error (g, _("filename cannot contain ',' (comma) character"));
return -1;
return -1;
}
- snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, DRIVE_IF);
+ size_t len = strlen (filename) + 64;
+ char buf[len];
+
+ snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, drive_if);
return guestfs__config (g, "-drive", buf);
}
int
+guestfs__add_drive (guestfs_h *g, const char *filename)
+{
+ return guestfs__add_drive_with_if (g, filename, DRIVE_IF);
+}
+
+int
+guestfs__add_drive_ro (guestfs_h *g, const char *filename)
+{
+ return guestfs__add_drive_ro_with_if (g, filename, DRIVE_IF);
+}
+
+int
guestfs__add_cdrom (guestfs_h *g, const char *filename)
{
if (strchr (filename, ',') != NULL) {
return 1;
}
+static void print_timestamped_message (guestfs_h *g, const char *fs, ...);
static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd);
-static int test_qemu (guestfs_h *g);
-static int qemu_supports (guestfs_h *g, const char *option);
+static int is_openable (guestfs_h *g, const char *path, int flags);
static void print_cmdline (guestfs_h *g);
static const char *kernel_name = "vmlinuz." REPO "." host_cpu;
int tries;
char *path, *pelem, *pend;
char *kernel = NULL, *initrd = NULL;
+ int null_vmchannel_sock;
char unixsock[256];
struct sockaddr_un addr;
-#ifdef P_tmpdir
- tmpdir = P_tmpdir;
-#else
- tmpdir = "/tmp";
-#endif
-
- tmpdir = getenv ("TMPDIR") ? : tmpdir;
- snprintf (dir_template, sizeof dir_template, "%s/libguestfsXXXXXX", tmpdir);
-
/* Configured? */
if (!g->cmdline) {
error (g, _("you must call guestfs_add_drive before guestfs_launch"));
}
if (g->state != CONFIG) {
- error (g, _("qemu has already been launched"));
+ error (g, _("the libguestfs handle has already been launched"));
return -1;
}
+ /* Start the clock ... */
+ gettimeofday (&g->launch_t, NULL);
+
/* Make the temporary directory. */
+#ifdef P_tmpdir
+ tmpdir = P_tmpdir;
+#else
+ tmpdir = "/tmp";
+#endif
+
+ tmpdir = getenv ("TMPDIR") ? : tmpdir;
+ snprintf (dir_template, sizeof dir_template, "%s/libguestfsXXXXXX", tmpdir);
+
if (!g->tmpdir) {
g->tmpdir = safe_strdup (g, dir_template);
if (mkdtemp (g->tmpdir) == NULL) {
goto cleanup0;
}
+ if (g->verbose)
+ print_timestamped_message (g, "begin testing qemu features");
+
/* Get qemu help text and version. */
- if (test_qemu (g) == -1)
+ if (qemu_supports (g, NULL) == -1)
goto cleanup0;
- /* Make the vmchannel socket. */
- snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
- unlink (unixsock);
+ /* Choose which vmchannel implementation to use. */
+ if (CAN_CHECK_PEER_EUID && qemu_supports (g, "-net user")) {
+ /* The "null vmchannel" implementation. Requires SLIRP (user mode
+ * networking in qemu) but no other vmchannel support. The daemon
+ * will connect back to a random port number on localhost.
+ */
+ struct sockaddr_in addr;
+ socklen_t addrlen = sizeof addr;
- if (pipe (wfd) == -1 || pipe (rfd) == -1) {
- perrorf (g, "pipe");
- goto cleanup0;
+ g->sock = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (g->sock == -1) {
+ perrorf (g, "socket");
+ goto cleanup0;
+ }
+ addr.sin_family = AF_INET;
+ addr.sin_port = htons (0);
+ addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
+ if (bind (g->sock, (struct sockaddr *) &addr, addrlen) == -1) {
+ perrorf (g, "bind");
+ goto cleanup0;
+ }
+
+ if (listen (g->sock, 256) == -1) {
+ perrorf (g, "listen");
+ goto cleanup0;
+ }
+
+ if (getsockname (g->sock, (struct sockaddr *) &addr, &addrlen) == -1) {
+ perrorf (g, "getsockname");
+ goto cleanup0;
+ }
+
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup0;
+ }
+
+ null_vmchannel_sock = ntohs (addr.sin_port);
+ if (g->verbose)
+ fprintf (stderr, "null_vmchannel_sock = %d\n", null_vmchannel_sock);
+ } else {
+ /* Using some vmchannel impl. We need to create a local Unix
+ * domain socket for qemu to use.
+ */
+ snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
+ unlink (unixsock);
+ null_vmchannel_sock = 0;
}
+ if (!g->direct) {
+ if (pipe (wfd) == -1 || pipe (rfd) == -1) {
+ perrorf (g, "pipe");
+ goto cleanup0;
+ }
+ }
+
+ if (g->verbose)
+ print_timestamped_message (g, "finished testing qemu features");
+
r = fork ();
if (r == -1) {
perrorf (g, "fork");
- close (wfd[0]);
- close (wfd[1]);
- close (rfd[0]);
- close (rfd[1]);
+ if (!g->direct) {
+ close (wfd[0]);
+ close (wfd[1]);
+ close (rfd[0]);
+ close (rfd[1]);
+ }
goto cleanup0;
}
if (r == 0) { /* Child (qemu). */
char buf[256];
- char append[256];
- char memsize_str[256];
+ const char *vmchannel = NULL;
/* Set up the full command line. Do this in the subprocess so we
* don't need to worry about cleaning up.
*/
g->cmdline[0] = g->qemu;
- snprintf (memsize_str, sizeof memsize_str, "%d", g->memsize);
+ /* qemu sometimes needs this option to enable hardware
+ * virtualization, but some versions of 'qemu-kvm' will use KVM
+ * regardless (even where this option appears in the help text).
+ * It is rumoured that there are versions of qemu where supplying
+ * this option when hardware virtualization is not available will
+ * cause qemu to fail, so we we have to check at least that
+ * /dev/kvm is openable. That's not reliable, since /dev/kvm
+ * might be openable by qemu but not by us (think: SELinux) in
+ * which case the user would not get hardware virtualization,
+ * although at least shouldn't fail. A giant clusterfuck with the
+ * qemu command line, again.
+ */
+ if (qemu_supports (g, "-enable-kvm") &&
+ is_openable (g, "/dev/kvm", O_RDWR))
+ add_cmdline (g, "-enable-kvm");
+
+ /* Newer versions of qemu (from around 2009/12) changed the
+ * behaviour of monitors so that an implicit '-monitor stdio' is
+ * assumed if we are in -nographic mode and there is no other
+ * -monitor option. Only a single stdio device is allowed, so
+ * this broke the '-serial stdio' option. There is a new flag
+ * called -nodefaults which gets rid of all this default crud, so
+ * let's use that to avoid this and any future surprises.
+ */
+ if (qemu_supports (g, "-nodefaults"))
+ add_cmdline (g, "-nodefaults");
- add_cmdline (g, "-m");
- add_cmdline (g, memsize_str);
- add_cmdline (g, "-no-reboot"); /* Force exit instead of reboot on panic */
add_cmdline (g, "-nographic");
add_cmdline (g, "-serial");
add_cmdline (g, "stdio");
+ snprintf (buf, sizeof buf, "%d", g->memsize);
+ add_cmdline (g, "-m");
+ add_cmdline (g, buf);
+
+ /* Force exit instead of reboot on panic */
+ add_cmdline (g, "-no-reboot");
+
/* These options recommended by KVM developers to improve reliability. */
if (qemu_supports (g, "-no-hpet"))
add_cmdline (g, "-no-hpet");
if (qemu_supports (g, "-rtc-td-hack"))
add_cmdline (g, "-rtc-td-hack");
- if (qemu_supports (g, "-chardev") && qemu_supports (g, "guestfwd")) {
- /* New-style -net user,guestfwd=... syntax for guestfwd. See:
- *
- * http://git.savannah.gnu.org/cgit/qemu.git/commit/?id=c92ef6a22d3c71538fcc48fb61ad353f7ba03b62
- *
- * The original suggested format doesn't work, see:
- *
- * http://lists.gnu.org/archive/html/qemu-devel/2009-07/msg01654.html
- *
- * However Gerd Hoffman privately suggested to me using -chardev
- * instead, which does work.
- */
+ /* If qemu has SLIRP (user mode network) enabled then we can get
+ * away with "no vmchannel", where we just connect back to a random
+ * host port.
+ */
+ if (null_vmchannel_sock) {
+ add_cmdline (g, "-net");
+ add_cmdline (g, "user,vlan=0,net=" NETWORK);
+
+ snprintf (buf, sizeof buf,
+ "guestfs_vmchannel=tcp:" ROUTER ":%d",
+ null_vmchannel_sock);
+ vmchannel = strdup (buf);
+ }
+
+ /* New-style -net user,guestfwd=... syntax for guestfwd. See:
+ *
+ * http://git.savannah.gnu.org/cgit/qemu.git/commit/?id=c92ef6a22d3c71538fcc48fb61ad353f7ba03b62
+ *
+ * The original suggested format doesn't work, see:
+ *
+ * http://lists.gnu.org/archive/html/qemu-devel/2009-07/msg01654.html
+ *
+ * However Gerd Hoffman privately suggested to me using -chardev
+ * instead, which does work.
+ */
+ else if (qemu_supports (g, "-chardev") && qemu_supports (g, "guestfwd")) {
snprintf (buf, sizeof buf,
"socket,id=guestfsvmc,path=%s,server,nowait", unixsock);
add_cmdline (g, buf);
snprintf (buf, sizeof buf,
- "user,vlan=0,net=10.0.2.0/8,"
- "guestfwd=tcp:%s:%d-chardev:guestfsvmc",
- GUESTFWD_ADDR, GUESTFWD_PORT);
+ "user,vlan=0,net=" NETWORK ","
+ "guestfwd=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT
+ "-chardev:guestfsvmc");
add_cmdline (g, "-net");
add_cmdline (g, buf);
- } else {
- /* Not guestfwd. HOPEFULLY this qemu uses the older -net channel
- * syntax, or if not then we'll get a quick failure.
- */
+
+ vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT;
+ }
+
+ /* Not guestfwd. HOPEFULLY this qemu uses the older -net channel
+ * syntax, or if not then we'll get a quick failure.
+ */
+ else {
snprintf (buf, sizeof buf,
- "channel,%d:unix:%s,server,nowait", GUESTFWD_PORT, unixsock);
+ "channel," GUESTFWD_PORT ":unix:%s,server,nowait", unixsock);
add_cmdline (g, "-net");
add_cmdline (g, buf);
add_cmdline (g, "-net");
- add_cmdline (g, "user,vlan=0,net=10.0.2.0/8");
+ add_cmdline (g, "user,vlan=0,net=" NETWORK);
+
+ vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT;
}
add_cmdline (g, "-net");
add_cmdline (g, "nic,model=" NET_IF ",vlan=0");
"udevtimeout=300 " /* good for very slow systems (RHBZ#480319) */ \
"noapic " /* workaround for RHBZ#502058 - ok if not SMP */ \
"acpi=off " /* we don't need ACPI, turn it off */ \
+ "printk.time=1 " /* display timestamp before kernel messages */ \
"cgroup_disable=memory " /* saves us about 5 MB of RAM */
/* Linux kernel command line. */
- snprintf (append, sizeof append,
+ snprintf (buf, sizeof buf,
LINUX_CMDLINE
- "%s" /* (selinux) */
- "%s" /* (verbose) */
+ "%s " /* (selinux) */
+ "%s " /* (vmchannel) */
+ "%s " /* (verbose) */
+ "TERM=%s " /* (TERM environment variable) */
"%s", /* (append) */
- g->selinux ? "selinux=1 enforcing=0 " : "selinux=0 ",
- g->verbose ? "guestfs_verbose=1 " : " ",
+ g->selinux ? "selinux=1 enforcing=0" : "selinux=0",
+ vmchannel ? vmchannel : "",
+ g->verbose ? "guestfs_verbose=1" : "",
+ getenv ("TERM") ? : "linux",
g->append ? g->append : "");
add_cmdline (g, "-kernel");
add_cmdline (g, "-initrd");
add_cmdline (g, (char *) initrd);
add_cmdline (g, "-append");
- add_cmdline (g, append);
+ add_cmdline (g, buf);
/* Finish off the command line. */
incr_cmdline_size (g);
if (g->verbose)
print_cmdline (g);
- /* Set up stdin, stdout. */
- close (0);
- close (1);
- close (wfd[1]);
- close (rfd[0]);
+ if (!g->direct) {
+ /* Set up stdin, stdout. */
+ close (0);
+ close (1);
+ close (wfd[1]);
+ close (rfd[0]);
+
+ if (dup (wfd[0]) == -1) {
+ dup_failed:
+ perror ("dup failed");
+ _exit (EXIT_FAILURE);
+ }
+ if (dup (rfd[1]) == -1)
+ goto dup_failed;
- if (dup (wfd[0]) == -1) {
- dup_failed:
- perror ("dup failed");
- _exit (1);
+ close (wfd[0]);
+ close (rfd[1]);
}
- if (dup (rfd[1]) == -1)
- goto dup_failed;
-
- close (wfd[0]);
- close (rfd[1]);
#if 0
/* Set up a new process group, so we can signal this process
setpgid (0, 0);
#endif
+ setenv ("LC_ALL", "C", 1);
+
execv (g->qemu, g->cmdline); /* Run qemu. */
perror (g->qemu);
- _exit (1);
+ _exit (EXIT_FAILURE);
}
/* Parent (library). */
/* Fork the recovery process off which will kill qemu if the parent
* process fails to do so (eg. if the parent segfaults).
*/
- r = fork ();
- if (r == 0) {
- pid_t qemu_pid = g->pid;
- pid_t parent_pid = getppid ();
+ g->recoverypid = -1;
+ if (g->recovery_proc) {
+ r = fork ();
+ if (r == 0) {
+ pid_t qemu_pid = g->pid;
+ pid_t parent_pid = getppid ();
+
+ /* Writing to argv is hideously complicated and error prone. See:
+ * http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?rev=1.33.2.1;content-type=text%2Fplain
+ */
- /* Writing to argv is hideously complicated and error prone. See:
- * http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/misc/ps_status.c?rev=1.33.2.1;content-type=text%2Fplain
+ /* Loop around waiting for one or both of the other processes to
+ * disappear. It's fair to say this is very hairy. The PIDs that
+ * we are looking at might be reused by another process. We are
+ * effectively polling. Is the cure worse than the disease?
+ */
+ for (;;) {
+ if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */
+ _exit (EXIT_SUCCESS);
+ if (kill (parent_pid, 0) == -1) {
+ /* Parent's gone away, qemu still around, so kill qemu. */
+ kill (qemu_pid, 9);
+ _exit (EXIT_SUCCESS);
+ }
+ sleep (2);
+ }
+ }
+
+ /* Don't worry, if the fork failed, this will be -1. The recovery
+ * process isn't essential.
*/
+ g->recoverypid = r;
+ }
+
+ if (!g->direct) {
+ /* Close the other ends of the pipe. */
+ close (wfd[0]);
+ close (rfd[1]);
+
+ if (fcntl (wfd[1], F_SETFL, O_NONBLOCK) == -1 ||
+ fcntl (rfd[0], F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
+
+ g->fd[0] = wfd[1]; /* stdin of child */
+ g->fd[1] = rfd[0]; /* stdout of child */
+ } else {
+ g->fd[0] = open ("/dev/null", O_RDWR);
+ if (g->fd[0] == -1) {
+ perrorf (g, "open /dev/null");
+ goto cleanup1;
+ }
+ g->fd[1] = dup (g->fd[0]);
+ if (g->fd[1] == -1) {
+ perrorf (g, "dup");
+ close (g->fd[0]);
+ goto cleanup1;
+ }
+ }
- /* Loop around waiting for one or both of the other processes to
- * disappear. It's fair to say this is very hairy. The PIDs that
- * we are looking at might be reused by another process. We are
- * effectively polling. Is the cure worse than the disease?
+ if (null_vmchannel_sock) {
+ int sock = -1;
+ uid_t uid;
+
+ /* Null vmchannel implementation: We listen on g->sock for a
+ * connection. The connection could come from any local process
+ * so we must check it comes from the appliance (or at least
+ * from our UID) for security reasons.
*/
- for (;;) {
- if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */
- _exit (0);
- if (kill (parent_pid, 0) == -1) {
- /* Parent's gone away, qemu still around, so kill qemu. */
- kill (qemu_pid, 9);
- _exit (0);
+ while (sock == -1) {
+ sock = accept_from_daemon (g);
+ if (sock == -1)
+ goto cleanup1;
+
+ if (check_peer_euid (g, sock, &uid) == -1)
+ goto cleanup1;
+ if (uid != geteuid ()) {
+ fprintf (stderr,
+ "libguestfs: warning: unexpected connection from UID %d to port %d\n",
+ uid, null_vmchannel_sock);
+ close (sock);
+ sock = -1;
+ continue;
}
- sleep (2);
}
- }
- /* Don't worry, if the fork failed, this will be -1. The recovery
- * process isn't essential.
- */
- g->recoverypid = r;
+ if (fcntl (sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
- /* Start the clock ... */
- time (&g->start_t);
+ close (g->sock);
+ g->sock = sock;
+ } else {
+ /* Other vmchannel. Open the Unix socket.
+ *
+ * The vmchannel implementation that got merged with qemu sucks in
+ * a number of ways. Both ends do connect(2), which means that no
+ * one knows what, if anything, is connected to the other end, or
+ * if it becomes disconnected. Even worse, we have to wait some
+ * indeterminate time for qemu to create the socket and connect to
+ * it (which happens very early in qemu's start-up), so any code
+ * that uses vmchannel is inherently racy. Hence this silly loop.
+ */
+ g->sock = socket (AF_UNIX, SOCK_STREAM, 0);
+ if (g->sock == -1) {
+ perrorf (g, "socket");
+ goto cleanup1;
+ }
- /* Close the other ends of the pipe. */
- close (wfd[0]);
- close (rfd[1]);
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup1;
+ }
- if (fcntl (wfd[1], F_SETFL, O_NONBLOCK) == -1 ||
- fcntl (rfd[0], F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
+ addr.sun_family = AF_UNIX;
+ strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
+ addr.sun_path[UNIX_PATH_MAX-1] = '\0';
+
+ tries = 100;
+ /* Always sleep at least once to give qemu a small chance to start up. */
+ usleep (10000);
+ while (tries > 0) {
+ r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr);
+ if ((r == -1 && errno == EINPROGRESS) || r == 0)
+ goto connected;
+
+ if (errno != ENOENT)
+ perrorf (g, "connect");
+ tries--;
+ usleep (100000);
+ }
+
+ error (g, _("failed to connect to vmchannel socket"));
goto cleanup1;
+
+ connected: ;
}
- g->fd[0] = wfd[1]; /* stdin of child */
- g->fd[1] = rfd[0]; /* stdout of child */
+ g->state = LAUNCHING;
- /* Open the Unix socket. The vmchannel implementation that got
- * merged with qemu sucks in a number of ways. Both ends do
- * connect(2), which means that no one knows what, if anything, is
- * connected to the other end, or if it becomes disconnected. Even
- * worse, we have to wait some indeterminate time for qemu to create
- * the socket and connect to it (which happens very early in qemu's
- * start-up), so any code that uses vmchannel is inherently racy.
- * Hence this silly loop.
+ /* Wait for qemu to start and to connect back to us via vmchannel and
+ * send the GUESTFS_LAUNCH_FLAG message.
*/
- g->sock = socket (AF_UNIX, SOCK_STREAM, 0);
- if (g->sock == -1) {
- perrorf (g, "socket");
- goto cleanup1;
- }
+ uint32_t size;
+ void *buf = NULL;
+ r = recv_from_daemon (g, &size, &buf);
+ free (buf);
- if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
- goto cleanup2;
- }
+ if (r == -1) return -1;
- addr.sun_family = AF_UNIX;
- strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
- addr.sun_path[UNIX_PATH_MAX-1] = '\0';
+ if (size != GUESTFS_LAUNCH_FLAG) {
+ error (g, _("guestfs_launch failed, see earlier error messages"));
+ goto cleanup1;
+ }
- tries = 100;
- /* Always sleep at least once to give qemu a small chance to start up. */
- usleep (10000);
- while (tries > 0) {
- r = connect (g->sock, (struct sockaddr *) &addr, sizeof addr);
- if ((r == -1 && errno == EINPROGRESS) || r == 0)
- goto connected;
+ if (g->verbose)
+ print_timestamped_message (g, "appliance is up");
- if (errno != ENOENT)
- perrorf (g, "connect");
- tries--;
- usleep (100000);
+ /* This is possible in some really strange situations, such as
+ * guestfsd starts up OK but then qemu immediately exits. Check for
+ * it because the caller is probably expecting to be able to send
+ * commands after this function returns.
+ */
+ if (g->state != READY) {
+ error (g, _("qemu launched and contacted daemon, but state != READY"));
+ goto cleanup1;
}
- error (g, _("failed to connect to vmchannel socket"));
- goto cleanup2;
-
- connected:
- g->state = LAUNCHING;
return 0;
- cleanup2:
- close (g->sock);
-
cleanup1:
- close (wfd[1]);
- close (rfd[0]);
- kill (g->pid, 9);
+ if (!g->direct) {
+ close (wfd[1]);
+ close (rfd[0]);
+ }
+ if (g->pid > 0) kill (g->pid, 9);
if (g->recoverypid > 0) kill (g->recoverypid, 9);
waitpid (g->pid, NULL, 0);
if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
g->fd[0] = -1;
g->fd[1] = -1;
- g->sock = -1;
g->pid = 0;
g->recoverypid = 0;
- g->start_t = 0;
+ memset (&g->launch_t, 0, sizeof g->launch_t);
cleanup0:
+ if (g->sock >= 0) {
+ close (g->sock);
+ g->sock = -1;
+ }
+ g->state = CONFIG;
free (kernel);
free (initrd);
return -1;
char cmd[4096];
int r, len;
+ if (g->verbose)
+ print_timestamped_message (g, "begin building supermin appliance");
+
len = strlen (g->tmpdir);
*kernel = safe_malloc (g, len + 8);
snprintf (*kernel, len+8, "%s/kernel", g->tmpdir);
snprintf (cmd, sizeof cmd,
"PATH='%s':$PATH "
- "libguestfs-supermin-helper '%s' %s %s",
+ "libguestfs-supermin-helper%s '%s' " host_cpu " " REPO " %s %s",
path,
+ g->verbose ? " --verbose" : "",
path, *kernel, *initrd);
+ if (g->verbose)
+ print_timestamped_message (g, "%s", cmd);
r = system (cmd);
if (r == -1 || WEXITSTATUS(r) != 0) {
return -1;
}
+ if (g->verbose)
+ print_timestamped_message (g, "finished building supermin appliance");
+
return 0;
}
+/* Compute Y - X and return the result in milliseconds.
+ * Approximately the same as this code:
+ * http://www.mpp.mpg.de/~huber/util/timevaldiff.c
+ */
+static int64_t
+timeval_diff (const struct timeval *x, const struct timeval *y)
+{
+ int64_t msec;
+
+ msec = (y->tv_sec - x->tv_sec) * 1000;
+ msec += (y->tv_usec - x->tv_usec) / 1000;
+ return msec;
+}
+
+static void
+print_timestamped_message (guestfs_h *g, const char *fs, ...)
+{
+ va_list args;
+ char *msg;
+ int err;
+ struct timeval tv;
+
+ va_start (args, fs);
+ err = vasprintf (&msg, fs, args);
+ va_end (args);
+
+ if (err < 0) return;
+
+ gettimeofday (&tv, NULL);
+
+ fprintf (stderr, "[%05" PRIi64 "ms] %s\n",
+ timeval_diff (&g->launch_t, &tv), msg);
+
+ free (msg);
+}
+
static int read_all (guestfs_h *g, FILE *fp, char **ret);
/* Test qemu binary (or wrapper) runs, and do 'qemu -help' and
char cmd[1024];
FILE *fp;
- free (g->qemu_help);
- free (g->qemu_version);
- g->qemu_help = NULL;
- g->qemu_version = NULL;
-
- snprintf (cmd, sizeof cmd, "'%s' -help", g->qemu);
+ snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -help", g->qemu);
fp = popen (cmd, "r");
/* qemu -help should always work (qemu -version OTOH wasn't
if (pclose (fp) == -1)
goto error;
- snprintf (cmd, sizeof cmd, "'%s' -version 2>/dev/null", g->qemu);
+ snprintf (cmd, sizeof cmd, "LC_ALL=C '%s' -nographic -version 2>/dev/null",
+ g->qemu);
fp = popen (cmd, "r");
if (fp) {
/* Test if option is supported by qemu command line (just by grepping
* the help text).
+ *
+ * The first time this is used, it has to run the external qemu
+ * binary. If that fails, it returns -1.
+ *
+ * To just do the first-time run of the qemu binary, call this with
+ * option == NULL, in which case it will return -1 if there was an
+ * error doing that.
*/
static int
qemu_supports (guestfs_h *g, const char *option)
{
- return g->qemu_help && strstr (g->qemu_help, option) != NULL;
+ if (!g->qemu_help) {
+ if (test_qemu (g) == -1)
+ return -1;
+ }
+
+ if (option == NULL)
+ return 1;
+
+ return strstr (g->qemu_help, option) != NULL;
}
-int
-guestfs__wait_ready (guestfs_h *g)
+/* Check if a file can be opened. */
+static int
+is_openable (guestfs_h *g, const char *path, int flags)
{
- int r;
- uint32_t size;
- void *buf = NULL;
+ int fd = open (path, flags);
+ if (fd == -1) {
+ if (g->verbose)
+ perror (path);
+ return 0;
+ }
+ close (fd);
+ return 1;
+}
- if (g->state == READY) return 0;
+/* Check the peer effective UID for a TCP socket. Ideally we'd like
+ * SO_PEERCRED for a loopback TCP socket. This isn't possible on
+ * Linux (but it is on Solaris!) so we read /proc/net/tcp instead.
+ */
+static int
+check_peer_euid (guestfs_h *g, int sock, uid_t *rtn)
+{
+#if CAN_CHECK_PEER_EUID
+ struct sockaddr_in peer;
+ socklen_t addrlen = sizeof peer;
- if (g->state == BUSY) {
- error (g, _("qemu has finished launching already"));
+ if (getpeername (sock, (struct sockaddr *) &peer, &addrlen) == -1) {
+ perrorf (g, "getpeername");
return -1;
}
- if (g->state != LAUNCHING) {
- error (g, _("qemu has not been launched yet"));
+ if (peer.sin_family != AF_INET ||
+ ntohl (peer.sin_addr.s_addr) != INADDR_LOOPBACK) {
+ error (g, "check_peer_euid: unexpected connection from non-IPv4, non-loopback peer (family = %d, addr = %s)",
+ peer.sin_family, inet_ntoa (peer.sin_addr));
return -1;
}
- r = recv_from_daemon (g, &size, &buf);
- free (buf);
+ struct sockaddr_in our;
+ addrlen = sizeof our;
+ if (getsockname (sock, (struct sockaddr *) &our, &addrlen) == -1) {
+ perrorf (g, "getsockname");
+ return -1;
+ }
- if (r == -1) return -1;
+ FILE *fp = fopen ("/proc/net/tcp", "r");
+ if (fp == NULL) {
+ perrorf (g, "/proc/net/tcp");
+ return -1;
+ }
- if (size != GUESTFS_LAUNCH_FLAG) {
- error (g, _("guestfs_wait_ready failed, see earlier error messages"));
+ char line[256];
+ if (fgets (line, sizeof line, fp) == NULL) { /* Drop first line. */
+ error (g, "unexpected end of file in /proc/net/tcp");
+ fclose (fp);
return -1;
}
- /* This is possible in some really strange situations, such as
- * guestfsd starts up OK but then qemu immediately exits. Check for
- * it because the caller is probably expecting to be able to send
- * commands after this function returns.
+ while (fgets (line, sizeof line, fp) != NULL) {
+ unsigned line_our_addr, line_our_port, line_peer_addr, line_peer_port;
+ int dummy0, dummy1, dummy2, dummy3, dummy4, dummy5, dummy6;
+ int line_uid;
+
+ if (sscanf (line, "%d:%08X:%04X %08X:%04X %02X %08X:%08X %02X:%08X %08X %d",
+ &dummy0,
+ &line_our_addr, &line_our_port,
+ &line_peer_addr, &line_peer_port,
+ &dummy1, &dummy2, &dummy3, &dummy4, &dummy5, &dummy6,
+ &line_uid) == 12) {
+ /* Note about /proc/net/tcp: local_address and rem_address are
+ * always in network byte order. However the port part is
+ * always in host byte order.
+ *
+ * The sockname and peername that we got above are in network
+ * byte order. So we have to byte swap the port but not the
+ * address part.
+ */
+ if (line_our_addr == our.sin_addr.s_addr &&
+ line_our_port == ntohs (our.sin_port) &&
+ line_peer_addr == peer.sin_addr.s_addr &&
+ line_peer_port == ntohs (peer.sin_port)) {
+ *rtn = line_uid;
+ fclose (fp);
+ return 0;
+ }
+ }
+ }
+
+ error (g, "check_peer_euid: no matching TCP connection found in /proc/net/tcp");
+ fclose (fp);
+ return -1;
+#else /* !CAN_CHECK_PEER_EUID */
+ /* This function exists but should never be called in this
+ * configuration.
*/
- if (g->state != READY) {
- error (g, _("qemu launched and contacted daemon, but state != READY"));
+ abort ();
+#endif /* !CAN_CHECK_PEER_EUID */
+}
+
+/* You had to call this function after launch in versions <= 1.0.70,
+ * but it is now a no-op.
+ */
+int
+guestfs__wait_ready (guestfs_h *g)
+{
+ if (g->state != READY) {
+ error (g, _("qemu has not been launched yet"));
return -1;
}
if (g->verbose)
fprintf (stderr, "sending SIGTERM to process %d\n", g->pid);
- kill (g->pid, SIGTERM);
+ if (g->pid > 0) kill (g->pid, SIGTERM);
if (g->recoverypid > 0) kill (g->recoverypid, 9);
return 0;
if (g->verbose)
fprintf (stderr, "child_cleanup: %p: child process died\n", g);
- /*kill (g->pid, SIGTERM);*/
+ /*if (g->pid > 0) kill (g->pid, SIGTERM);*/
if (g->recoverypid > 0) kill (g->recoverypid, 9);
waitpid (g->pid, NULL, 0);
if (g->recoverypid > 0) waitpid (g->recoverypid, NULL, 0);
g->sock = -1;
g->pid = 0;
g->recoverypid = 0;
- g->start_t = 0;
+ memset (&g->launch_t, 0, sizeof g->launch_t);
g->state = CONFIG;
if (g->subprocess_quit_cb)
g->subprocess_quit_cb (g, g->subprocess_quit_cb_data);
}
static int
-read_log_message_or_eof (guestfs_h *g, int fd)
+read_log_message_or_eof (guestfs_h *g, int fd, int error_if_eof)
{
char buf[BUFSIZ];
int n;
if (n == 0) {
/* Hopefully this indicates the qemu child process has died. */
child_cleanup (g);
+
+ if (error_if_eof) {
+ /* We weren't expecting eof here (called from launch) so place
+ * something in the error buffer. RHBZ#588851.
+ */
+ error (g, "child process died unexpectedly");
+ }
return -1;
}
FD_SET (g->sock, &rset); /* Read socket for cancellation & EOF. */
FD_SET (g->sock, &wset); /* Write to socket to send the data. */
- int max_fd = g->sock > g->fd[1] ? g->sock : g->fd[1];
+ int max_fd = MAX (g->sock, g->fd[1]);
while (n > 0) {
rset2 = rset;
}
if (FD_ISSET (g->fd[1], &rset2)) {
- if (read_log_message_or_eof (g, g->fd[1]) == -1)
+ if (read_log_message_or_eof (g, g->fd[1], 0) == -1)
return -1;
}
if (FD_ISSET (g->sock, &rset2)) {
FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
FD_SET (g->sock, &rset); /* Read socket for data & EOF. */
- int max_fd = g->sock > g->fd[1] ? g->sock : g->fd[1];
+ int max_fd = MAX (g->sock, g->fd[1]);
*size_rtn = 0;
*buf_rtn = NULL;
}
if (FD_ISSET (g->fd[1], &rset2)) {
- if (read_log_message_or_eof (g, g->fd[1]) == -1) {
+ if (read_log_message_or_eof (g, g->fd[1], 0) == -1) {
free (*buf_rtn);
*buf_rtn = NULL;
return -1;
printf (" ");
printf ("|");
for (j = i; j < MIN (i+16, nr); ++j)
- if (isprint ((*(char **)buf_rtn)[j]))
+ if (c_isprint ((*(char **)buf_rtn)[j]))
printf ("%c", (*(char **)buf_rtn)[j]);
else
printf (".");
return 0;
}
+/* This is very much like recv_from_daemon above, but g->sock is
+ * a listening socket and we are accepting a new connection on
+ * that socket instead of reading anything. Returns the newly
+ * accepted socket.
+ */
+static int
+accept_from_daemon (guestfs_h *g)
+{
+ fd_set rset, rset2;
+
+ if (g->verbose)
+ fprintf (stderr,
+ "accept_from_daemon: %p g->state = %d\n", g, g->state);
+
+ FD_ZERO (&rset);
+
+ FD_SET (g->fd[1], &rset); /* Read qemu stdout for log messages & EOF. */
+ FD_SET (g->sock, &rset); /* Read socket for accept. */
+
+ int max_fd = MAX (g->sock, g->fd[1]);
+ int sock = -1;
+
+ while (sock == -1) {
+ /* If the qemu process has died, clean up the zombie (RHBZ#579155).
+ * By partially polling in the select below we ensure that this
+ * function will be called eventually.
+ */
+ waitpid (g->pid, NULL, WNOHANG);
+
+ rset2 = rset;
+
+ struct timeval tv = { .tv_sec = 1, .tv_usec = 0 };
+ int r = select (max_fd+1, &rset2, NULL, NULL, &tv);
+ if (r == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "select");
+ return -1;
+ }
+
+ if (FD_ISSET (g->fd[1], &rset2)) {
+ if (read_log_message_or_eof (g, g->fd[1], 1) == -1)
+ return -1;
+ }
+ if (FD_ISSET (g->sock, &rset2)) {
+ sock = accept (g->sock, NULL, NULL);
+ if (sock == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ perrorf (g, "accept");
+ return -1;
+ }
+ }
+ }
+
+ return sock;
+}
+
int
guestfs___send (guestfs_h *g, int proc_nr, xdrproc_t xdrp, char *args)
{
{
void *buf;
int fd, r;
- size_t len;
fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666);
if (fd == -1) {