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/*
* Virtio 9p Posix callback
*
* Copyright IBM, Corp. 2010
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "virtio.h"
#include "virtio-9p.h"
#include <pwd.h>
#include <grp.h>
static const char *rpath(FsContext *ctx, const char *path)
{
/* FIXME: so wrong... */
static char buffer[4096];
snprintf(buffer, sizeof(buffer), "%s/%s", ctx->fs_root, path);
return buffer;
}
static int local_lstat(FsContext *ctx, const char *path, struct stat *stbuf)
{
return lstat(rpath(ctx, path), stbuf);
}
static int local_setuid(FsContext *ctx, uid_t uid)
{
struct passwd *pw;
gid_t groups[33];
int ngroups;
static uid_t cur_uid = -1;
if (cur_uid == uid) {
return 0;
}
if (setreuid(0, 0)) {
return -1;
}
pw = getpwuid(uid);
if (pw == NULL) {
return -1;
}
ngroups = 33;
if (getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups) == -1) {
return -1;
}
if (setgroups(ngroups, groups)) {
return -1;
}
if (setregid(-1, pw->pw_gid)) {
return -1;
}
if (setreuid(-1, uid)) {
return -1;
}
cur_uid = uid;
return 0;
}
static ssize_t local_readlink(FsContext *ctx, const char *path,
char *buf, size_t bufsz)
{
return readlink(rpath(ctx, path), buf, bufsz);
}
static int local_close(FsContext *ctx, int fd)
{
return close(fd);
}
static int local_closedir(FsContext *ctx, DIR *dir)
{
return closedir(dir);
}
static int local_open(FsContext *ctx, const char *path, int flags)
{
return open(rpath(ctx, path), flags);
}
static DIR *local_opendir(FsContext *ctx, const char *path)
{
return opendir(rpath(ctx, path));
}
FileOperations local_ops = {
.lstat = local_lstat,
.setuid = local_setuid,
.readlink = local_readlink,
.close = local_close,
.closedir = local_closedir,
.open = local_open,
.opendir = local_opendir,
};
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