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#include <kvm/util.h>
#include <kvm/kvm-cmd.h>
#include <kvm/builtin-setup.h>
#include <kvm/kvm.h>
#include <kvm/parse-options.h>
#include <kvm/read-write.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <limits.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <sys/mman.h>
#include <fcntl.h>
static const char *instance_name;
static const char * const setup_usage[] = {
"lkvm setup [name]",
NULL
};
static const struct option setup_options[] = {
OPT_END()
};
static void parse_setup_options(int argc, const char **argv)
{
while (argc != 0) {
argc = parse_options(argc, argv, setup_options, setup_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (argc != 0 && instance_name)
kvm_setup_help();
else
instance_name = argv[0];
argv++;
argc--;
}
}
void kvm_setup_help(void)
{
printf("\n%s setup creates a new rootfs under %s.\n"
"This can be used later by the '-d' parameter of '%s run'.\n",
KVM_BINARY_NAME, kvm__get_dir(), KVM_BINARY_NAME);
usage_with_options(setup_usage, setup_options);
}
static int copy_file(const char *from, const char *to)
{
int in_fd, out_fd;
void *src, *dst;
struct stat st;
int err = -1;
in_fd = open(from, O_RDONLY);
if (in_fd < 0)
return err;
if (fstat(in_fd, &st) < 0)
goto error_close_in;
out_fd = open(to, O_RDWR | O_CREAT | O_TRUNC, st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO));
if (out_fd < 0)
goto error_close_in;
src = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, in_fd, 0);
if (src == MAP_FAILED)
goto error_close_out;
if (ftruncate(out_fd, st.st_size) < 0)
goto error_munmap_src;
dst = mmap(NULL, st.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, out_fd, 0);
if (dst == MAP_FAILED)
goto error_munmap_src;
memcpy(dst, src, st.st_size);
if (fsync(out_fd) < 0)
goto error_munmap_dst;
err = 0;
error_munmap_dst:
munmap(dst, st.st_size);
error_munmap_src:
munmap(src, st.st_size);
error_close_out:
close(out_fd);
error_close_in:
close(in_fd);
return err;
}
static const char *guestfs_dirs[] = {
"/dev",
"/etc",
"/home",
"/host",
"/proc",
"/root",
"/sys",
"/tmp",
"/var",
"/var/lib",
"/virt",
"/virt/home",
};
static const char *guestfs_symlinks[] = {
"/bin",
"/lib",
"/lib64",
"/sbin",
"/usr",
"/etc/ld.so.conf",
};
#ifdef CONFIG_GUEST_INIT
extern char _binary_guest_init_start;
extern char _binary_guest_init_size;
int kvm_setup_guest_init(const char *guestfs_name)
{
char path[PATH_MAX];
size_t size;
int fd, ret;
char *data;
size = (size_t)&_binary_guest_init_size;
data = (char *)&_binary_guest_init_start;
snprintf(path, PATH_MAX, "%s%s/virt/init", kvm__get_dir(), guestfs_name);
remove(path);
fd = open(path, O_CREAT | O_WRONLY, 0755);
if (fd < 0)
die("Fail to setup %s", path);
ret = xwrite(fd, data, size);
if (ret < 0)
die("Fail to setup %s", path);
close(fd);
return 0;
}
#else
int kvm_setup_guest_init(const char *guestfs_name)
{
die("Guest init image not compiled in");
return 0;
}
#endif
static int copy_passwd(const char *guestfs_name)
{
char path[PATH_MAX];
FILE *file;
int ret;
snprintf(path, PATH_MAX, "%s%s/etc/passwd", kvm__get_dir(), guestfs_name);
file = fopen(path, "w");
if (!file)
return -1;
ret = fprintf(file, "root:x:0:0:root:/root:/bin/sh\n");
if (ret > 0)
ret = 0;
fclose(file);
return ret;
}
static int make_guestfs_symlink(const char *guestfs_name, const char *path)
{
char target[PATH_MAX];
char name[PATH_MAX];
snprintf(name, PATH_MAX, "%s%s%s", kvm__get_dir(), guestfs_name, path);
snprintf(target, PATH_MAX, "/host%s", path);
return symlink(target, name);
}
static int make_dir(const char *dir)
{
char name[PATH_MAX];
snprintf(name, PATH_MAX, "%s%s", kvm__get_dir(), dir);
return mkdir(name, 0777);
}
static void make_guestfs_dir(const char *guestfs_name, const char *dir)
{
char name[PATH_MAX];
snprintf(name, PATH_MAX, "%s%s", guestfs_name, dir);
make_dir(name);
}
void kvm_setup_resolv(const char *guestfs_name)
{
char path[PATH_MAX];
snprintf(path, PATH_MAX, "%s%s/etc/resolv.conf", kvm__get_dir(), guestfs_name);
copy_file("/etc/resolv.conf", path);
}
static int do_setup(const char *guestfs_name)
{
unsigned int i;
int ret;
ret = make_dir(guestfs_name);
if (ret < 0)
return ret;
for (i = 0; i < ARRAY_SIZE(guestfs_dirs); i++)
make_guestfs_dir(guestfs_name, guestfs_dirs[i]);
for (i = 0; i < ARRAY_SIZE(guestfs_symlinks); i++) {
make_guestfs_symlink(guestfs_name, guestfs_symlinks[i]);
}
ret = kvm_setup_guest_init(guestfs_name);
if (ret < 0)
return ret;
return copy_passwd(guestfs_name);
}
int kvm_setup_create_new(const char *guestfs_name)
{
return do_setup(guestfs_name);
}
int kvm_cmd_setup(int argc, const char **argv, const char *prefix)
{
int r;
parse_setup_options(argc, argv);
if (instance_name == NULL)
kvm_setup_help();
r = do_setup(instance_name);
if (r == 0)
printf("A new rootfs '%s' has been created in '%s%s'.\n\n"
"You can now start it by running the following command:\n\n"
" %s run -d %s\n",
instance_name, kvm__get_dir(), instance_name,
KVM_BINARY_NAME,instance_name);
else
printf("Unable to create rootfs in %s%s: %s\n",
kvm__get_dir(), instance_name, strerror(errno));
return r;
}
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