X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Fguestfs.c;h=0e4cb73bc2a259c395b2a2739299693499c673f8;hp=4c94c325238d80783ccdc1f8bc869361a0023f9d;hb=1214b321621e7750c67423ecf4d9528809e1eeac;hpb=ade327a7af869d4d70e28e2a596473943e0299dd diff --git a/src/guestfs.c b/src/guestfs.c index 4c94c32..0e4cb73 100644 --- a/src/guestfs.c +++ b/src/guestfs.c @@ -1,5 +1,5 @@ /* 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 @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -60,12 +61,14 @@ #include #include +#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 "c-ctype.h" -#include "ignore-value.h" #ifdef HAVE_GETTEXT #include "gettext.h" @@ -83,17 +86,51 @@ #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_ADDR "10.0.2.4" +#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 "169.254.0.0/16" +#define ROUTER "169.254.2.2" +#define GUESTFWD_ADDR "169.254.2.4" #define GUESTFWD_PORT "6666" /* GuestFS handle and connection. */ @@ -150,6 +187,7 @@ struct guestfs_h int msg_next_serial; }; +gl_lock_define_initialized (static, handles_lock); static guestfs_h *handles = NULL; static int atexit_handler_set = 0; @@ -217,17 +255,15 @@ guestfs_create (void) */ 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); @@ -312,7 +348,7 @@ guestfs_close (guestfs_h *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 { @@ -320,7 +356,7 @@ guestfs_close (guestfs_h *g) ; gg->next = g->next; } - /* release mutex (XXX) */ + gl_lock_unlock (handles_lock); free (g->last_error); free (g->path); @@ -388,7 +424,7 @@ guestfs_perrorf (guestfs_h *g, const char *fs, ...) if (err < 0) return; -#ifndef _GNU_SOURCE +#if !defined(_GNU_SOURCE) || defined(__APPLE__) char buf[256]; strerror_r (errnum, buf, sizeof buf); #else @@ -432,7 +468,11 @@ guestfs_safe_malloc (guestfs_h *g, size_t nbytes) /* 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. */ @@ -747,7 +787,8 @@ guestfs__config (guestfs_h *g, } 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]; @@ -770,12 +811,12 @@ guestfs__add_drive (guestfs_h *g, const char *filename) 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; @@ -786,11 +827,9 @@ guestfs__add_drive (guestfs_h *g, const char *filename) } 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; @@ -801,12 +840,41 @@ guestfs__add_drive_ro (guestfs_h *g, const char *filename) return -1; } - snprintf (buf, len, "file=%s,snapshot=on,if=%s", filename, DRIVE_IF); + if (qemu_supports (g, NULL) == -1) + return -1; + + /* Only SCSI and virtio drivers support readonly mode. + * This is only supported as a QEMU feature since 2010/01. + */ + int supports_ro = 0; + if ((STREQ (drive_if, "scsi") || STREQ (drive_if, "virtio")) && + qemu_supports (g, "readonly=on")) + supports_ro = 1; + + size_t len = strlen (filename) + 100; + char buf[len]; + + snprintf (buf, len, "file=%s,snapshot=on,%sif=%s", + filename, + supports_ro ? "readonly=on," : "", + 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) { @@ -855,16 +923,11 @@ dir_contains_files (const char *dir, ...) 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; static const char *initrd_name = "initramfs." REPO "." host_cpu ".img"; -static const char *supermin_name = - "initramfs." REPO "." host_cpu ".supermin.img"; -static const char *supermin_hostfiles_name = - "initramfs." REPO "." host_cpu ".supermin.hostfiles"; int guestfs__launch (guestfs_h *g) @@ -881,9 +944,21 @@ guestfs__launch (guestfs_h *g) char unixsock[256]; struct sockaddr_un addr; + /* Configured? */ + if (!g->cmdline) { + error (g, _("you must call guestfs_add_drive before guestfs_launch")); + return -1; + } + + if (g->state != CONFIG) { + 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 @@ -893,18 +968,6 @@ guestfs__launch (guestfs_h *g) 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")); - return -1; - } - - if (g->state != CONFIG) { - error (g, _("qemu has already been launched")); - return -1; - } - - /* Make the temporary directory. */ if (!g->tmpdir) { g->tmpdir = safe_strdup (g, dir_template); if (mkdtemp (g->tmpdir) == NULL) { @@ -931,8 +994,7 @@ guestfs__launch (guestfs_h *g) fprintf (stderr, "looking for supermin appliance in current directory\n"); if (dir_contains_files (".", - supermin_name, supermin_hostfiles_name, - "kmod.whitelist", NULL)) { + "supermin.d", "kmod.whitelist", NULL)) { if (build_supermin_appliance (g, ".", &kernel, &initrd) == -1) return -1; break; @@ -944,8 +1006,7 @@ guestfs__launch (guestfs_h *g) fprintf (stderr, "looking for supermin appliance in %s\n", pelem); if (dir_contains_files (pelem, - supermin_name, supermin_hostfiles_name, - "kmod.whitelist", NULL)) { + "supermin.d", "kmod.whitelist", NULL)) { if (build_supermin_appliance (g, pelem, &kernel, &initrd) == -1) return -1; break; @@ -1007,11 +1068,11 @@ guestfs__launch (guestfs_h *g) 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; /* Choose which vmchannel implementation to use. */ - if (qemu_supports (g, "-net user")) { + 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. @@ -1090,15 +1151,44 @@ guestfs__launch (guestfs_h *g) */ g->cmdline[0] = g->qemu; - snprintf (buf, sizeof buf, "%d", g->memsize); - add_cmdline (g, "-m"); - add_cmdline (g, buf); + /* 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, "-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"); @@ -1112,10 +1202,11 @@ guestfs__launch (guestfs_h *g) */ if (null_vmchannel_sock) { add_cmdline (g, "-net"); - add_cmdline (g, "user,vlan=0,net=10.0.2.0/8"); + add_cmdline (g, "user,vlan=0,net=" NETWORK); snprintf (buf, sizeof buf, - "guestfs_vmchannel=tcp:10.0.2.2:%d", null_vmchannel_sock); + "guestfs_vmchannel=tcp:" ROUTER ":%d", + null_vmchannel_sock); vmchannel = strdup (buf); } @@ -1138,7 +1229,7 @@ guestfs__launch (guestfs_h *g) add_cmdline (g, buf); snprintf (buf, sizeof buf, - "user,vlan=0,net=10.0.2.0/8," + "user,vlan=0,net=" NETWORK "," "guestfwd=tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT "-chardev:guestfsvmc"); @@ -1158,7 +1249,7 @@ guestfs__launch (guestfs_h *g) 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; } @@ -1180,10 +1271,12 @@ guestfs__launch (guestfs_h *g) "%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"); @@ -1210,7 +1303,7 @@ guestfs__launch (guestfs_h *g) if (dup (wfd[0]) == -1) { dup_failed: perror ("dup failed"); - _exit (1); + _exit (EXIT_FAILURE); } if (dup (rfd[1]) == -1) goto dup_failed; @@ -1230,7 +1323,7 @@ guestfs__launch (guestfs_h *g) execv (g->qemu, g->cmdline); /* Run qemu. */ perror (g->qemu); - _exit (1); + _exit (EXIT_FAILURE); } /* Parent (library). */ @@ -1262,11 +1355,11 @@ guestfs__launch (guestfs_h *g) */ for (;;) { if (kill (qemu_pid, 0) == -1) /* qemu's gone away, we aren't needed */ - _exit (0); + _exit (EXIT_SUCCESS); if (kill (parent_pid, 0) == -1) { /* Parent's gone away, qemu still around, so kill qemu. */ kill (qemu_pid, 9); - _exit (0); + _exit (EXIT_SUCCESS); } sleep (2); } @@ -1326,6 +1419,7 @@ guestfs__launch (guestfs_h *g) "libguestfs: warning: unexpected connection from UID %d to port %d\n", uid, null_vmchannel_sock); close (sock); + sock = -1; continue; } } @@ -1420,7 +1514,7 @@ guestfs__launch (guestfs_h *g) close (wfd[1]); close (rfd[0]); } - kill (g->pid, 9); + 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); @@ -1491,10 +1585,17 @@ build_supermin_appliance (guestfs_h *g, const char *path, snprintf (*initrd, len+8, "%s/initrd", g->tmpdir); snprintf (cmd, sizeof cmd, - "PATH='%s':$PATH " - "libguestfs-supermin-helper '%s' %s %s", + "febootstrap-supermin-helper%s " + "-k '%s/kmod.whitelist' " + "'%s/supermin.d' " + host_cpu " " + "%s %s", + g->verbose ? " --verbose" : "", path, - path, *kernel, *initrd); + path, + *kernel, *initrd); + if (g->verbose) + print_timestamped_message (g, "%s", cmd); r = system (cmd); if (r == -1 || WEXITSTATUS(r) != 0) { @@ -1531,7 +1632,7 @@ print_timestamped_message (guestfs_h *g, const char *fs, ...) va_list args; char *msg; int err; - struct timeval tv, diff; + struct timeval tv; va_start (args, fs); err = vasprintf (&msg, fs, args); @@ -1559,12 +1660,7 @@ test_qemu (guestfs_h *g) 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, "LC_ALL=C '%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 @@ -1586,7 +1682,8 @@ test_qemu (guestfs_h *g) if (pclose (fp) == -1) goto error; - snprintf (cmd, sizeof cmd, "LC_ALL=C '%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) { @@ -1624,11 +1721,40 @@ read_all (guestfs_h *g, FILE *fp, char **ret) /* 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; +} + +/* Check if a file can be opened. */ +static int +is_openable (guestfs_h *g, const char *path, int flags) +{ + int fd = open (path, flags); + if (fd == -1) { + if (g->verbose) + perror (path); + return 0; + } + close (fd); + return 1; } /* Check the peer effective UID for a TCP socket. Ideally we'd like @@ -1638,6 +1764,7 @@ qemu_supports (guestfs_h *g, const char *option) 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; @@ -1706,6 +1833,12 @@ check_peer_euid (guestfs_h *g, int sock, uid_t *rtn) 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, @@ -1733,7 +1866,7 @@ guestfs__kill_subprocess (guestfs_h *g) 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; @@ -1884,7 +2017,7 @@ child_cleanup (guestfs_h *g) 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); @@ -1903,7 +2036,7 @@ child_cleanup (guestfs_h *g) } 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; @@ -1924,6 +2057,13 @@ read_log_message_or_eof (guestfs_h *g, int fd) 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; } @@ -2031,7 +2171,7 @@ send_to_daemon (guestfs_h *g, const void *v_buf, size_t n) } 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)) { @@ -2114,7 +2254,7 @@ recv_from_daemon (guestfs_h *g, uint32_t *size_rtn, void **buf_rtn) } 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; @@ -2251,8 +2391,16 @@ accept_from_daemon (guestfs_h *g) 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; - int r = select (max_fd+1, &rset2, NULL, NULL, NULL); + + 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; @@ -2261,7 +2409,7 @@ accept_from_daemon (guestfs_h *g) } 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], 1) == -1) return -1; } if (FD_ISSET (g->sock, &rset2)) { @@ -2572,7 +2720,6 @@ guestfs___recv_file (guestfs_h *g, const char *filename) { void *buf; int fd, r; - size_t len; fd = open (filename, O_WRONLY|O_CREAT|O_TRUNC|O_NOCTTY, 0666); if (fd == -1) {