/* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009 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
#include <sys/select.h>
#include <sys/types.h>
#include <sys/wait.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <signal.h>
#include "daemon.h"
struct addrinfo hints;
XDR xdr;
uint32_t len;
+ struct sigaction sa;
for (;;) {
c = getopt_long (argc, argv, options, long_options, NULL);
port = VMCHANNEL_PORT;
}
+ /* Make sure SIGPIPE doesn't kill us. */
+ memset (&sa, 0, sizeof sa);
+ sa.sa_handler = SIG_IGN;
+ sa.sa_flags = 0;
+ if (sigaction (SIGPIPE, &sa, NULL) == -1)
+ perror ("sigaction SIGPIPE"); /* but try to continue anyway ... */
+
+ /* Set up a basic environment. After we are called by /init the
+ * environment is essentially empty.
+ * https://bugzilla.redhat.com/show_bug.cgi?id=502074#c5
+ */
+ setenv ("PATH", "/usr/bin:/bin", 1);
+ setenv ("SHELL", "/bin/sh", 1);
+ setenv ("LANG", "C", 1);
+
+ /* We document that umask defaults to 022 (it should be this anyway). */
+ umask (022);
+
/* Resolve the hostname. */
memset (&hints, 0, sizeof hints);
hints.ai_socktype = SOCK_STREAM;
command (char **stdoutput, char **stderror, const char *name, ...)
{
va_list args;
- char **argv;
+ char **argv, **p;
char *s;
int i, r;
/* Collect the command line arguments into an array. */
+ i = 2;
+ argv = malloc (sizeof (char *) * i);
+ if (argv == NULL) {
+ perror ("malloc");
+ return -1;
+ }
+ argv[0] = (char *) name;
+ argv[1] = NULL;
+
va_start (args, name);
+ while ((s = va_arg (args, char *)) != NULL) {
+ p = realloc (argv, sizeof (char *) * (++i));
+ if (p == NULL) {
+ perror ("realloc");
+ free (argv);
+ va_end (args);
+ return -1;
+ }
+ argv = p;
+ argv[i-2] = s;
+ argv[i-1] = NULL;
+ }
+
+ va_end (args);
+
+ r = commandv (stdoutput, stderror, argv);
+
+ /* NB: Mustn't free the strings which are on the stack. */
+ free (argv);
+
+ return r;
+}
+
+/* Same as 'command', but we allow the status code from the
+ * subcommand to be non-zero, and return that status code.
+ * We still return -1 if there was some other error.
+ */
+int
+commandr (char **stdoutput, char **stderror, const char *name, ...)
+{
+ va_list args;
+ char **argv, **p;
+ char *s;
+ int i, r;
+
+ /* Collect the command line arguments into an array. */
i = 2;
argv = malloc (sizeof (char *) * i);
+ if (argv == NULL) {
+ perror ("malloc");
+ return -1;
+ }
argv[0] = (char *) name;
argv[1] = NULL;
+ va_start (args, name);
+
while ((s = va_arg (args, char *)) != NULL) {
- argv = realloc (argv, sizeof (char *) * (++i));
+ p = realloc (argv, sizeof (char *) * (++i));
+ if (p == NULL) {
+ perror ("realloc");
+ free (argv);
+ va_end (args);
+ return -1;
+ }
+ argv = p;
argv[i-2] = s;
argv[i-1] = NULL;
}
va_end (args);
- r = commandv (stdoutput, stderror, argv);
+ r = commandrv (stdoutput, stderror, argv);
/* NB: Mustn't free the strings which are on the stack. */
free (argv);
return r;
}
+/* Same as 'command', but passing an argv. */
int
commandv (char **stdoutput, char **stderror, char * const* const argv)
{
+ int r;
+
+ r = commandrv (stdoutput, stderror, argv);
+ if (r == 0)
+ return 0;
+ else
+ return -1;
+}
+
+int
+commandrv (char **stdoutput, char **stderror, char * const* const argv)
+{
int so_size = 0, se_size = 0;
int so_fd[2], se_fd[2];
- int pid, r, quit, i;
+ pid_t pid;
+ int r, quit, i;
fd_set rset, rset2;
char buf[256];
+ char *p;
if (stdoutput) *stdoutput = NULL;
if (stderror) *stderror = NULL;
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;
}
r = select (MAX (so_fd[0], se_fd[0]) + 1, &rset2, NULL, NULL, NULL);
if (r == -1) {
perror ("select");
+ quit:
+ if (stdoutput) free (*stdoutput);
+ if (stderror) free (*stderror);
+ close (so_fd[0]);
+ close (se_fd[0]);
waitpid (pid, NULL, 0);
return -1;
}
r = read (so_fd[0], buf, sizeof buf);
if (r == -1) {
perror ("read");
- waitpid (pid, NULL, 0);
- return -1;
+ goto quit;
}
if (r == 0) { FD_CLR (so_fd[0], &rset); quit++; }
if (r > 0 && stdoutput) {
so_size += r;
- *stdoutput = realloc (*stdoutput, so_size);
- if (*stdoutput == NULL) {
+ p = realloc (*stdoutput, so_size);
+ if (p == NULL) {
perror ("realloc");
- *stdoutput = NULL;
- continue;
+ goto quit;
}
+ *stdoutput = p;
memcpy (*stdoutput + so_size - r, buf, r);
}
}
r = read (se_fd[0], buf, sizeof buf);
if (r == -1) {
perror ("read");
- waitpid (pid, NULL, 0);
- return -1;
+ goto quit;
}
if (r == 0) { FD_CLR (se_fd[0], &rset); quit++; }
if (r > 0 && stderror) {
se_size += r;
- *stderror = realloc (*stderror, se_size);
- if (*stderror == NULL) {
+ p = realloc (*stderror, se_size);
+ if (p == NULL) {
perror ("realloc");
- *stderror = NULL;
- continue;
+ goto quit;
}
+ *stderror = p;
memcpy (*stderror + se_size - r, buf, r);
}
}
}
+ close (so_fd[0]);
+ close (se_fd[0]);
+
/* Make sure the output buffers are \0-terminated. Also remove any
* trailing \n characters from the error buffer (not from stdout).
*/
if (stdoutput) {
- *stdoutput = realloc (*stdoutput, so_size+1);
- if (*stdoutput == NULL) {
+ void *q = realloc (*stdoutput, so_size+1);
+ if (q == NULL) {
perror ("realloc");
- *stdoutput = NULL;
- } else
+ free (*stdoutput);
+ }
+ *stdoutput = q;
+ if (*stdoutput)
(*stdoutput)[so_size] = '\0';
}
if (stderror) {
- *stderror = realloc (*stderror, se_size+1);
- if (*stderror == NULL) {
+ void *q = realloc (*stderror, se_size+1);
+ if (q == NULL) {
perror ("realloc");
- *stderror = NULL;
- } else {
+ free (*stderror);
+ }
+ *stderror = q;
+ if (*stderror) {
(*stderror)[se_size] = '\0';
se_size--;
while (se_size >= 0 && (*stderror)[se_size] == '\n')
}
/* Get the exit status of the command. */
- waitpid (pid, &r, 0);
+ if (waitpid (pid, &r, 0) != pid) {
+ perror ("waitpid");
+ return -1;
+ }
if (WIFEXITED (r)) {
- if (WEXITSTATUS (r) == 0)
- return 0;
- else
- return -1;
+ return WEXITSTATUS (r);
} else
return -1;
}
+
+/* Split an output string into a NULL-terminated list of lines.
+ * Typically this is used where we have run an external command
+ * which has printed out a list of things, and we want to return
+ * an actual list.
+ *
+ * The corner cases here are quite tricky. Note in particular:
+ *
+ * "" -> []
+ * "\n" -> [""]
+ * "a\nb" -> ["a"; "b"]
+ * "a\nb\n" -> ["a"; "b"]
+ * "a\nb\n\n" -> ["a"; "b"; ""]
+ *
+ * The original string is written over and destroyed by this
+ * function (which is usually OK because it's the 'out' string
+ * from command()). You can free the original string, because
+ * add_string() strdups the strings.
+ */
+char **
+split_lines (char *str)
+{
+ char **lines = NULL;
+ int size = 0, alloc = 0;
+ char *p, *pend;
+
+ if (strcmp (str, "") == 0)
+ goto empty_list;
+
+ p = str;
+ while (p) {
+ /* Empty last line? */
+ if (p[0] == '\0')
+ break;
+
+ pend = strchr (p, '\n');
+ if (pend) {
+ *pend = '\0';
+ pend++;
+ }
+
+ if (add_string (&lines, &size, &alloc, p) == -1) {
+ return NULL;
+ }
+
+ p = pend;
+ }
+
+ empty_list:
+ if (add_string (&lines, &size, &alloc, NULL) == -1)
+ return NULL;
+
+ return lines;
+}
+
+/* Quote 'in' for the shell, and write max len-1 bytes to out. The
+ * result will be NUL-terminated, even if it is truncated.
+ *
+ * Returns number of bytes needed, so if result >= len then the buffer
+ * should have been longer.
+ *
+ * XXX This doesn't quote \n correctly (but is still safe).
+ */
+int
+shell_quote (char *out, int len, const char *in)
+{
+#define SAFE(c) (isalnum((c)) || \
+ (c) == '/' || (c) == '-' || (c) == '_' || (c) == '.')
+ int i, j;
+ int outlen = strlen (in);
+
+ /* Calculate how much output space this really needs. */
+ for (i = 0; in[i]; ++i)
+ if (!SAFE (in[i])) outlen++;
+
+ /* Now copy the string, but only up to len-1 bytes. */
+ for (i = 0, j = 0; in[i]; ++i) {
+ int is_safe = SAFE (in[i]);
+
+ /* Enough space left to write this character? */
+ if (j >= len-1 || (!is_safe && j >= len-2))
+ break;
+
+ if (!is_safe) out[j++] = '\\';
+ out[j++] = in[i];
+ }
+
+ out[j] = '\0';
+
+ return outlen;
+}
+
+/* Perform device name translation. Don't call this directly -
+ * use the IS_DEVICE macro.
+ *
+ * See guestfs(3) for the algorithm.
+ *
+ * We have to open the device and test for ENXIO, because
+ * the device nodes themselves will exist in the appliance.
+ */
+int
+device_name_translation (char *device, const char *func)
+{
+ int fd;
+
+ fd = open (device, O_RDONLY);
+ if (fd >= 0) {
+ close (fd);
+ return 0;
+ }
+
+ if (errno != ENXIO && errno != ENOENT) {
+ error:
+ reply_with_perror ("%s: %s", func, device);
+ return -1;
+ }
+
+ /* If the name begins with "/dev/sd" then try the alternatives. */
+ if (strncmp (device, "/dev/sd", 7) != 0)
+ goto error;
+
+ device[5] = 'h'; /* /dev/hd (old IDE driver) */
+ fd = open (device, O_RDONLY);
+ if (fd >= 0) {
+ close (fd);
+ return 0;
+ }
+
+ device[5] = 'v'; /* /dev/vd (for virtio devices) */
+ fd = open (device, O_RDONLY);
+ if (fd >= 0) {
+ close (fd);
+ return 0;
+ }
+
+ device[5] = 's'; /* Restore original device name. */
+ goto error;
+}
+
+/* LVM and other commands aren't synchronous, especially when udev is
+ * involved. eg. You can create or remove some device, but the /dev
+ * device node won't appear until some time later. This means that
+ * you get an error if you run one command followed by another.
+ * Use 'udevadm settle' after certain commands, but don't be too
+ * fussed if it fails.
+ */
+void
+udev_settle (void)
+{
+ command (NULL, NULL, "/sbin/udevadm", "settle", NULL);
+}