X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Fguestfsd.c;h=cd51f442486c1537c37618abed1fdf6495926ea0;hp=84b62ab58e3602aec93fc949e0aa2b5cbe4f9315;hb=07369cb77a07f965cbf8e02f485c78a22c091f85;hpb=9e0b31a2af26b8d58a44dd80993a5e73d4942307 diff --git a/daemon/guestfsd.c b/daemon/guestfsd.c index 84b62ab..cd51f44 100644 --- a/daemon/guestfsd.c +++ b/daemon/guestfsd.c @@ -1,5 +1,5 @@ /* libguestfs - the guestfsd daemon - * Copyright (C) 2009 Red Hat Inc. + * Copyright (C) 2009-2010 Red Hat Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -55,9 +55,14 @@ static char *read_cmdline (void); -/* Also in guestfs.c */ -#define GUESTFWD_ADDR "10.0.2.4" -#define GUESTFWD_PORT "6666" +/* This is the default address we connect to for very old libraries + * which didn't specify the address and port number explicitly on the + * kernel command line. It's now recommended to always specify the + * address and port number on the command line, so this will not be + * used any more. + */ +#define OLD_GUESTFWD_ADDR "10.0.2.4" +#define OLD_GUESTFWD_PORT "6666" /* This is only a hint. If not defined, ignore it. */ #ifndef AI_ADDRCONFIG @@ -227,6 +232,7 @@ main (int argc, char *argv[]) setenv ("PATH", "/sbin:/usr/sbin:/bin:/usr/bin", 1); setenv ("SHELL", "/bin/sh", 1); setenv ("LC_ALL", "C", 1); + setenv ("TERM", "dumb", 1); #ifndef WIN32 /* We document that umask defaults to 022 (it should be this anyway). */ @@ -284,7 +290,7 @@ main (int argc, char *argv[]) /* Default vmchannel. */ if (vmchannel == NULL) { - vmchannel = strdup ("tcp:" GUESTFWD_ADDR ":" GUESTFWD_PORT); + vmchannel = strdup ("tcp:" OLD_GUESTFWD_ADDR ":" OLD_GUESTFWD_PORT); if (!vmchannel) { perror ("strdup"); exit (EXIT_FAILURE); @@ -709,6 +715,14 @@ commandvf (char **stdoutput, char **stderror, int flags, * error messages in the *stderror buffer. If using this flag, * you should pass stdoutput as NULL because nothing could ever be * captured in that buffer. + * + * COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN: For running external + * commands on chrooted files correctly (see RHBZ#579608) specifying + * this flag causes another process to be forked which chroots into + * sysroot and just copies the input file to stdin of the specified + * command. The file descriptor is ORed with the flags, and that file + * descriptor is always closed by this function. See hexdump.c for an + * example of usage. */ int commandrvf (char **stdoutput, char **stderror, int flags, @@ -716,7 +730,9 @@ commandrvf (char **stdoutput, char **stderror, int flags, { int so_size = 0, se_size = 0; int so_fd[2], se_fd[2]; - pid_t pid; + int flag_copy_stdin = flags & COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN; + int stdin_fd[2] = { -1, -1 }; + pid_t pid, stdin_pid = -1; int r, quit, i; fd_set rset, rset2; char buf[256]; @@ -732,24 +748,42 @@ commandrvf (char **stdoutput, char **stderror, int flags, printf ("\n"); } + /* Note: abort is used in a few places along the error paths early + * in this function. This is because (a) cleaning up correctly is + * very complex at these places and (b) abort is used when a + * resource problems is indicated which would be due to much more + * serious issues - eg. memory or file descriptor leaks. We + * wouldn't expect fork(2) or pipe(2) to fail in normal + * circumstances. + */ + if (pipe (so_fd) == -1 || pipe (se_fd) == -1) { perror ("pipe"); - return -1; + abort (); + } + + if (flag_copy_stdin) { + if (pipe (stdin_fd) == -1) { + perror ("pipe"); + abort (); + } } pid = fork (); if (pid == -1) { perror ("fork"); - close (so_fd[0]); - close (so_fd[1]); - close (se_fd[0]); - close (se_fd[1]); - return -1; + abort (); } - if (pid == 0) { /* Child process. */ + if (pid == 0) { /* Child process running the command. */ close (0); - open ("/dev/null", O_RDONLY); /* Set stdin to /dev/null (ignore failure) */ + if (flag_copy_stdin) { + dup2 (stdin_fd[0], 0); + close (stdin_fd[0]); + close (stdin_fd[1]); + } else + /* Set stdin to /dev/null (ignore failure) */ + open ("/dev/null", O_RDONLY); close (so_fd[0]); close (se_fd[0]); if (!(flags & COMMAND_FLAG_FOLD_STDOUT_ON_STDERR)) @@ -762,7 +796,61 @@ commandrvf (char **stdoutput, char **stderror, int flags, execvp (argv[0], (void *) argv); perror (argv[0]); - _exit (1); + _exit (EXIT_FAILURE); + } + + if (flag_copy_stdin) { + int fd = flags & COMMAND_FLAG_FD_MASK; + + stdin_pid = fork (); + if (stdin_pid == -1) { + perror ("fork"); + abort (); + } + + if (stdin_pid == 0) { /* Child process copying stdin. */ + close (so_fd[0]); + close (so_fd[1]); + close (se_fd[0]); + close (se_fd[1]); + + close (1); + dup2 (stdin_fd[1], 1); + close (stdin_fd[0]); + close (stdin_fd[1]); + + if (chroot (sysroot) == -1) { + perror ("chroot"); + _exit (EXIT_FAILURE); + } + + ssize_t n; + char buffer[BUFSIZ]; + while ((n = read (fd, buffer, sizeof buffer)) > 0) { + if (xwrite (1, buffer, n) == -1) + /* EPIPE error indicates the command process has exited + * early. If the command process fails that will be caught + * by the daemon, and if not, then it's not an error. + */ + _exit (errno == EPIPE ? EXIT_SUCCESS : EXIT_FAILURE); + } + + if (n == -1) { + perror ("read"); + _exit (EXIT_FAILURE); + } + + if (close (fd) == -1) { + perror ("close"); + _exit (EXIT_FAILURE); + } + + _exit (EXIT_SUCCESS); + } + + close (fd); + close (stdin_fd[0]); + close (stdin_fd[1]); } /* Parent process. */ @@ -785,6 +873,7 @@ commandrvf (char **stdoutput, char **stderror, int flags, close (so_fd[0]); close (se_fd[0]); waitpid (pid, NULL, 0); + if (stdin_pid >= 0) waitpid (stdin_pid, NULL, 0); return -1; } @@ -865,6 +954,23 @@ commandrvf (char **stdoutput, char **stderror, int flags, } } + if (flag_copy_stdin) { + /* Check copy process didn't fail. */ + if (waitpid (stdin_pid, &r, 0) != stdin_pid) { + perror ("waitpid"); + kill (pid, 9); + waitpid (pid, NULL, 0); + return -1; + } + + if (!WIFEXITED (r) || WEXITSTATUS (r) != 0) { + fprintf (stderr, "failed copying from input file, see earlier messages\n"); + kill (pid, 9); + waitpid (pid, NULL, 0); + return -1; + } + } + /* Get the exit status of the command. */ if (waitpid (pid, &r, 0) != pid) { perror ("waitpid"); @@ -1021,42 +1127,36 @@ print_arginfo (const struct printf_info *info, size_t n, int *argtypes) * the device nodes themselves will exist in the appliance. */ int -device_name_translation (char *device, const char *func) +device_name_translation (char *device) { int fd; fd = open (device, O_RDONLY); if (fd >= 0) { + close_ok: close (fd); return 0; } - if (errno != ENXIO && errno != ENOENT) { - error: - reply_with_perror ("%s: %s", func, device); + if (errno != ENXIO && errno != ENOENT) return -1; - } /* If the name begins with "/dev/sd" then try the alternatives. */ if (STRNEQLEN (device, "/dev/sd", 7)) - goto error; + return -1; device[5] = 'h'; /* /dev/hd (old IDE driver) */ fd = open (device, O_RDONLY); - if (fd >= 0) { - close (fd); - return 0; - } + if (fd >= 0) + goto close_ok; device[5] = 'v'; /* /dev/vd (for virtio devices) */ fd = open (device, O_RDONLY); - if (fd >= 0) { - close (fd); - return 0; - } + if (fd >= 0) + goto close_ok; device[5] = 's'; /* Restore original device name. */ - goto error; + return -1; } /* Check program exists and is executable on $PATH. Actually, we @@ -1065,7 +1165,7 @@ device_name_translation (char *device, const char *func) int prog_exists (const char *prog) { - static const char *dirs[] = + static const char * const dirs[] = { "/sbin", "/usr/sbin", "/bin", "/usr/bin" }; size_t i; char buf[1024];