#include "guestfs-internal-actions.h"
#include "guestfs_protocol.h"
-static int check_peer_euid (guestfs_h *g, int sock, uid_t *rtn);
static int qemu_supports (guestfs_h *g, const char *option);
/* Add a string to the current command line. */
return guestfs__config (g, "-cdrom", filename);
}
-/* Returns true iff file is contained in dir. */
-static int
-dir_contains_file (const char *dir, const char *file)
-{
- int dirlen = strlen (dir);
- int filelen = strlen (file);
- int len = dirlen+filelen+2;
- char path[len];
-
- snprintf (path, len, "%s/%s", dir, file);
- return access (path, F_OK) == 0;
-}
-
-/* Returns true iff every listed file is contained in 'dir'. */
-static int
-dir_contains_files (const char *dir, ...)
-{
- va_list args;
- const char *file;
-
- va_start (args, dir);
- while ((file = va_arg (args, const char *)) != NULL) {
- if (!dir_contains_file (dir, file)) {
- va_end (args);
- return 0;
- }
- }
- va_end (args);
- return 1;
-}
-
-static int build_supermin_appliance (guestfs_h *g, const char *path, char **kernel, char **initrd);
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;
-static const char *initrd_name = "initramfs." REPO "." host_cpu ".img";
-
int
guestfs__launch (guestfs_h *g)
{
- int r, pmore;
- size_t len;
+ int r;
int wfd[2], rfd[2];
int tries;
- char *path, *pelem, *pend;
- char *kernel = NULL, *initrd = NULL;
- int null_vmchannel_sock;
char unixsock[256];
struct sockaddr_un addr;
}
}
- /* Allow anyone to read the temporary directory. There are no
- * secrets in the kernel or initrd files. The socket in this
+ /* Allow anyone to read the temporary directory. The socket in this
* directory won't be readable but anyone can see it exists if they
* want. (RHBZ#610880).
*/
if (chmod (g->tmpdir, 0755) == -1)
fprintf (stderr, "chmod: %s: %m (ignored)\n", g->tmpdir);
- /* First search g->path for the supermin appliance, and try to
- * synthesize a kernel and initrd from that. If it fails, we
- * try the path search again looking for a backup ordinary
- * appliance.
- */
- pelem = path = safe_strdup (g, g->path);
- do {
- pend = strchrnul (pelem, ':');
- pmore = *pend == ':';
- *pend = '\0';
- len = pend - pelem;
-
- /* Empty element of "." means cwd. */
- if (len == 0 || (len == 1 && *pelem == '.')) {
- if (g->verbose)
- fprintf (stderr,
- "looking for supermin appliance in current directory\n");
- if (dir_contains_files (".",
- "supermin.d", "kmod.whitelist", NULL)) {
- if (build_supermin_appliance (g, ".", &kernel, &initrd) == -1)
- return -1;
- break;
- }
- }
- /* Look at <path>/supermin* etc. */
- else {
- if (g->verbose)
- fprintf (stderr, "looking for supermin appliance in %s\n", pelem);
-
- if (dir_contains_files (pelem,
- "supermin.d", "kmod.whitelist", NULL)) {
- if (build_supermin_appliance (g, pelem, &kernel, &initrd) == -1)
- return -1;
- break;
- }
- }
-
- pelem = pend + 1;
- } while (pmore);
-
- free (path);
-
- if (kernel == NULL || initrd == NULL) {
- /* Search g->path for the kernel and initrd. */
- pelem = path = safe_strdup (g, g->path);
- do {
- pend = strchrnul (pelem, ':');
- pmore = *pend == ':';
- *pend = '\0';
- len = pend - pelem;
-
- /* Empty element or "." means cwd. */
- if (len == 0 || (len == 1 && *pelem == '.')) {
- if (g->verbose)
- fprintf (stderr,
- "looking for appliance in current directory\n");
- if (dir_contains_files (".", kernel_name, initrd_name, NULL)) {
- kernel = safe_strdup (g, kernel_name);
- initrd = safe_strdup (g, initrd_name);
- break;
- }
- }
- /* Look at <path>/kernel etc. */
- else {
- if (g->verbose)
- fprintf (stderr, "looking for appliance in %s\n", pelem);
-
- if (dir_contains_files (pelem, kernel_name, initrd_name, NULL)) {
- kernel = safe_malloc (g, len + strlen (kernel_name) + 2);
- initrd = safe_malloc (g, len + strlen (initrd_name) + 2);
- sprintf (kernel, "%s/%s", pelem, kernel_name);
- sprintf (initrd, "%s/%s", pelem, initrd_name);
- break;
- }
- }
-
- pelem = pend + 1;
- } while (pmore);
-
- free (path);
- }
-
- if (kernel == NULL || initrd == NULL) {
- error (g, _("cannot find %s or %s on LIBGUESTFS_PATH (current path = %s)"),
- kernel_name, initrd_name, g->path);
- goto cleanup0;
- }
+ /* Locate and/or build the appliance. */
+ char *kernel = NULL, *initrd = NULL, *appliance = NULL;
+ if (guestfs___build_appliance (g, &kernel, &initrd, &appliance) == -1)
+ return -1;
if (g->verbose)
guestfs___print_timestamped_message (g, "begin testing qemu features");
if (qemu_supports (g, NULL) == -1)
goto cleanup0;
- /* 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;
+ /* Using virtio-serial, we need to create a local Unix domain socket
+ * for qemu to connect to.
+ */
+ snprintf (unixsock, sizeof unixsock, "%s/sock", g->tmpdir);
+ unlink (unixsock);
- 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;
- }
+ g->sock = socket (AF_UNIX, SOCK_STREAM, 0);
+ if (g->sock == -1) {
+ perrorf (g, "socket");
+ goto cleanup0;
+ }
- if (listen (g->sock, 256) == -1) {
- perrorf (g, "listen");
- goto cleanup0;
- }
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
+ goto cleanup0;
+ }
- if (getsockname (g->sock, (struct sockaddr *) &addr, &addrlen) == -1) {
- perrorf (g, "getsockname");
- goto cleanup0;
- }
+ addr.sun_family = AF_UNIX;
+ strncpy (addr.sun_path, unixsock, UNIX_PATH_MAX);
+ addr.sun_path[UNIX_PATH_MAX-1] = '\0';
- if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
- goto cleanup0;
- }
+ if (bind (g->sock, &addr, sizeof addr) == -1) {
+ perrorf (g, "bind");
+ 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 (listen (g->sock, 1) == -1) {
+ perrorf (g, "listen");
+ goto cleanup0;
}
if (!g->direct) {
if (r == 0) { /* Child (qemu). */
char buf[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;
+ if (qemu_supports (g, "-nodefconfig"))
+ add_cmdline (g, "-nodefconfig");
+
/* 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).
add_cmdline (g, "-nodefaults");
add_cmdline (g, "-nographic");
- add_cmdline (g, "-serial");
- add_cmdline (g, "stdio");
snprintf (buf, sizeof buf, "%d", g->memsize);
add_cmdline (g, "-m");
if (qemu_supports (g, "-rtc-td-hack"))
add_cmdline (g, "-rtc-td-hack");
- /* 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, "-chardev");
- add_cmdline (g, buf);
-
- snprintf (buf, sizeof buf,
- "user,vlan=0,net=" NETWORK ","
- "guestfwd=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT
- "-chardev:guestfsvmc");
-
- add_cmdline (g, "-net");
- add_cmdline (g, buf);
+ /* Create the virtio serial bus. */
+ add_cmdline (g, "-device");
+ add_cmdline (g, "virtio-serial");
- 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.
+#if 0
+ /* Use virtio-console (a variant form of virtio-serial) for the
+ * guest's serial console.
*/
- else {
- snprintf (buf, sizeof buf,
- "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=" NETWORK);
+ add_cmdline (g, "-chardev");
+ add_cmdline (g, "stdio,id=console");
+ add_cmdline (g, "-device");
+ add_cmdline (g, "virtconsole,chardev=console,name=org.libguestfs.console.0");
+#else
+ /* When the above works ... until then: */
+ add_cmdline (g, "-serial");
+ add_cmdline (g, "stdio");
+#endif
- vmchannel = "guestfs_vmchannel=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT;
+ /* Set up virtio-serial for the communications channel. */
+ add_cmdline (g, "-chardev");
+ snprintf (buf, sizeof buf, "socket,path=%s,id=channel0", unixsock);
+ add_cmdline (g, buf);
+ add_cmdline (g, "-device");
+ add_cmdline (g, "virtserialport,chardev=channel0,name=org.libguestfs.channel.0");
+
+ /* Enable user networking. */
+ if (g->enable_network) {
+ add_cmdline (g, "-netdev");
+ add_cmdline (g, "user,id=usernet");
+ add_cmdline (g, "-device");
+ add_cmdline (g, NET_IF ",netdev=usernet");
}
- add_cmdline (g, "-net");
- add_cmdline (g, "nic,model=" NET_IF ",vlan=0");
#define LINUX_CMDLINE \
"panic=1 " /* force kernel to panic if daemon exits */ \
snprintf (buf, sizeof buf,
LINUX_CMDLINE
"%s " /* (selinux) */
- "%s " /* (vmchannel) */
"%s " /* (verbose) */
"TERM=%s " /* (TERM environment variable) */
"%s", /* (append) */
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, (char *) kernel);
+ add_cmdline (g, kernel);
add_cmdline (g, "-initrd");
- add_cmdline (g, (char *) initrd);
+ add_cmdline (g, initrd);
add_cmdline (g, "-append");
add_cmdline (g, buf);
+ /* Add the ext2 appliance drive (last of all). */
+ if (appliance) {
+ const char *cachemode = "";
+ if (qemu_supports (g, "cache=")) {
+ if (qemu_supports (g, "unsafe"))
+ cachemode = ",cache=unsafe";
+ else if (qemu_supports (g, "writeback"))
+ cachemode = ",cache=writeback";
+ }
+
+ char buf2[PATH_MAX + 64];
+ add_cmdline (g, "-drive");
+ snprintf (buf2, sizeof buf2, "file=%s,snapshot=on,if=" DRIVE_IF "%s",
+ appliance, cachemode);
+ add_cmdline (g, buf2);
+ }
+
/* Finish off the command line. */
incr_cmdline_size (g);
g->cmdline[g->cmdline_size-1] = NULL;
}
}
- 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.
- */
- while (sock == -1) {
- sock = guestfs___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;
- }
- }
-
- if (fcntl (sock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
- goto cleanup1;
- }
-
- 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;
- }
+ g->state = LAUNCHING;
- if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
- perrorf (g, "fcntl");
- goto cleanup1;
- }
+ /* Wait for qemu to start and to connect back to us via
+ * virtio-serial and send the GUESTFS_LAUNCH_FLAG message.
+ */
+ r = guestfs___accept_from_daemon (g);
+ if (r == -1)
+ goto cleanup1;
- 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);
- }
+ close (g->sock); /* Close the listening socket. */
+ g->sock = r; /* This is the accepted data socket. */
- error (g, _("failed to connect to vmchannel socket"));
+ if (fcntl (g->sock, F_SETFL, O_NONBLOCK) == -1) {
+ perrorf (g, "fcntl");
goto cleanup1;
-
- connected: ;
}
- g->state = LAUNCHING;
-
- /* Wait for qemu to start and to connect back to us via vmchannel and
- * send the GUESTFS_LAUNCH_FLAG message.
- */
uint32_t size;
void *buf = NULL;
r = guestfs___recv_from_daemon (g, &size, &buf);
g->state = CONFIG;
free (kernel);
free (initrd);
+ free (appliance);
return -1;
}
fputc ('\n', stderr);
}
-/* This function does the hard work of building the supermin appliance
- * on the fly. 'path' is the directory containing the control files.
- * 'kernel' and 'initrd' are where we will return the names of the
- * kernel and initrd (only initrd is built). The work is done by
- * an external script. We just tell it where to put the result.
- */
-static int
-build_supermin_appliance (guestfs_h *g, const char *path,
- char **kernel, char **initrd)
-{
- 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);
- *initrd = safe_malloc (g, len + 8);
- snprintf (*initrd, len+8, "%s/initrd", g->tmpdir);
-
- /* Set a sensible umask in the subprocess, so kernel and initrd
- * output files are world-readable (RHBZ#610880).
- */
- snprintf (cmd, sizeof cmd,
- "umask 0002; "
- "febootstrap-supermin-helper%s "
- "-k '%s/kmod.whitelist' "
- "'%s/supermin.d' "
- host_cpu " "
- "%s %s",
- g->verbose ? " --verbose" : "",
- path,
- path,
- *kernel, *initrd);
- if (g->verbose)
- print_timestamped_message (g, "%s", cmd);
-
- r = system (cmd);
- if (r == -1 || WEXITSTATUS(r) != 0) {
- error (g, _("external command failed: %s"), cmd);
- free (*kernel);
- free (*initrd);
- *kernel = *initrd = NULL;
- 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
return 1;
}
-/* 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 (getpeername (sock, (struct sockaddr *) &peer, &addrlen) == -1) {
- perrorf (g, "getpeername");
- return -1;
- }
-
- 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;
- }
-
- struct sockaddr_in our;
- addrlen = sizeof our;
- if (getsockname (sock, (struct sockaddr *) &our, &addrlen) == -1) {
- perrorf (g, "getsockname");
- return -1;
- }
-
- FILE *fp = fopen ("/proc/net/tcp", "r");
- if (fp == NULL) {
- perrorf (g, "/proc/net/tcp");
- return -1;
- }
-
- 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;
- }
-
- 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.
- */
- 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.
*/
git.annexia.org / libguestfs.git / blobdiff