/* * 9p user. xattr callback * * Copyright IBM, Corp. 2010 * * Authors: * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> * * This work is licensed under the terms of the GNU GPL, version 2. See * the COPYING file in the top-level directory. * */ /* * Not so fast! You might want to read the 9p developer docs first: * https://wiki.qemu.org/Documentation/9p */ #include "qemu/osdep.h" #include "9p.h" #include "fsdev/file-op-9p.h" #include "9p-xattr.h" static ssize_t mp_user_getxattr(FsContext *ctx, const char *path, const char *name, void *value, size_t size) { if (strncmp(name, "user.virtfs.", 12) == 0) { /* * Don't allow fetch of user.virtfs namespace * in case of mapped security */ errno = ENOATTR; return -1; } return local_getxattr_nofollow(ctx, path, name, value, size); } static ssize_t mp_user_listxattr(FsContext *ctx, const char *path, char *name, void *value, size_t size) { int name_size = strlen(name) + 1; if (strncmp(name, "user.virtfs.", 12) == 0) { /* check if it is a mapped posix acl */ if (strncmp(name, "user.virtfs.system.posix_acl_", 29) == 0) { /* adjust the name and size */ name += 12; name_size -= 12; } else { /* * Don't allow fetch of user.virtfs namespace * in case of mapped security */ return 0; } } if (!value) { return name_size; } if (size < name_size) { errno = ERANGE; return -1; } /* name_size includes the trailing NUL. */ memcpy(value, name, name_size); return name_size; } static int mp_user_setxattr(FsContext *ctx, const char *path, const char *name, void *value, size_t size, int flags) { if (strncmp(name, "user.virtfs.", 12) == 0) { /* * Don't allow fetch of user.virtfs namespace * in case of mapped security */ errno = EACCES; return -1; } return local_setxattr_nofollow(ctx, path, name, value, size, flags); } static int mp_user_removexattr(FsContext *ctx, const char *path, const char *name) { if (strncmp(name, "user.virtfs.", 12) == 0) { /* * Don't allow fetch of user.virtfs namespace * in case of mapped security */ errno = EACCES; return -1; } return local_removexattr_nofollow(ctx, path, name); } XattrOperations mapped_user_xattr = { .name = "user.", .getxattr = mp_user_getxattr, .setxattr = mp_user_setxattr, .listxattr = mp_user_listxattr, .removexattr = mp_user_removexattr, }; XattrOperations passthrough_user_xattr = { .name = "user.", .getxattr = pt_getxattr, .setxattr = pt_setxattr, .listxattr = pt_listxattr, .removexattr = pt_removexattr, };