text: // SPDX-License-Identifier: GPL-2.0-or-later
  /* 32-bit compatibility syscall for 64-bit systems
   *
   * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
   * Written by David Howells (dhowells@redhat.com)
   */
  
  #include <linux/syscalls.h>
  #include <linux/keyctl.h>
  #include <linux/compat.h>
  #include <linux/slab.h>
  #include "internal.h"
  
  /*
   * Instantiate a key with the specified compatibility multipart payload and
   * link the key into the destination keyring if one is given.
   *
   * The caller must have the appropriate instantiation permit set for this to
   * work (see keyctl_assume_authority).  No other permissions are required.
   *
   * If successful, 0 will be returned.
   */
  static long compat_keyctl_instantiate_key_iov(
  	key_serial_t id,
  	const struct compat_iovec __user *_payload_iov,
  	unsigned ioc,
  	key_serial_t ringid)
  {
  	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
  	struct iov_iter from;
  	long ret;
  
  	if (!_payload_iov)
  		ioc = 0;
  
  	ret = compat_import_iovec(WRITE, _payload_iov, ioc,
  				  ARRAY_SIZE(iovstack), &iov,
  				  &from);
  	if (ret < 0)
  		return ret;
  
  	ret = keyctl_instantiate_key_common(id, &from, ringid);
  	kfree(iov);
  	return ret;
  }
  
  /*
   * The key control system call, 32-bit compatibility version for 64-bit archs
   *
   * This should only be called if the 64-bit arch uses weird pointers in 32-bit
   * mode or doesn't guarantee that the top 32-bits of the argument registers on
   * taking a 32-bit syscall are zero.  If you can, you should call sys_keyctl()
   * directly.
   */
  COMPAT_SYSCALL_DEFINE5(keyctl, u32, option,
  		       u32, arg2, u32, arg3, u32, arg4, u32, arg5)
  {
  	switch (option) {
  	case KEYCTL_GET_KEYRING_ID:
  		return keyctl_get_keyring_ID(arg2, arg3);
  
  	case KEYCTL_JOIN_SESSION_KEYRING:
  		return keyctl_join_session_keyring(compat_ptr(arg2));
  
  	case KEYCTL_UPDATE:
  		return keyctl_update_key(arg2, compat_ptr(arg3), arg4);
  
  	case KEYCTL_REVOKE:
  		return keyctl_revoke_key(arg2);
  
  	case KEYCTL_DESCRIBE:
  		return keyctl_describe_key(arg2, compat_ptr(arg3), arg4);
  
  	case KEYCTL_CLEAR:
  		return keyctl_keyring_clear(arg2);
  
  	case KEYCTL_LINK:
  		return keyctl_keyring_link(arg2, arg3);
  
  	case KEYCTL_UNLINK:
  		return keyctl_keyring_unlink(arg2, arg3);
  
  	case KEYCTL_SEARCH:
  		return keyctl_keyring_search(arg2, compat_ptr(arg3),
  					     compat_ptr(arg4), arg5);
  
  	case KEYCTL_READ:
  		return keyctl_read_key(arg2, compat_ptr(arg3), arg4);
  
  	case KEYCTL_CHOWN:
  		return keyctl_chown_key(arg2, arg3, arg4);
  
  	case KEYCTL_SETPERM:
  		return keyctl_setperm_key(arg2, arg3);
  
  	case KEYCTL_INSTANTIATE:
  		return keyctl_instantiate_key(arg2, compat_ptr(arg3), arg4,
  					      arg5);
  
  	case KEYCTL_NEGATE:
  		return keyctl_negate_key(arg2, arg3, arg4);
  
  	case KEYCTL_SET_REQKEY_KEYRING:
  		return keyctl_set_reqkey_keyring(arg2);
  
  	case KEYCTL_SET_TIMEOUT:
  		return keyctl_set_timeout(arg2, arg3);
  
  	case KEYCTL_ASSUME_AUTHORITY:
  		return keyctl_assume_authority(arg2);
  
  	case KEYCTL_GET_SECURITY:
  		return keyctl_get_security(arg2, compat_ptr(arg3), arg4);
  
  	case KEYCTL_SESSION_TO_PARENT:
  		return keyctl_session_to_parent();
  
  	case KEYCTL_REJECT:
  		return keyctl_reject_key(arg2, arg3, arg4, arg5);
  
  	case KEYCTL_INSTANTIATE_IOV:
  		return compat_keyctl_instantiate_key_iov(
  			arg2, compat_ptr(arg3), arg4, arg5);
  
  	case KEYCTL_INVALIDATE:
  		return keyctl_invalidate_key(arg2);
  
  	case KEYCTL_GET_PERSISTENT:
  		return keyctl_get_persistent(arg2, arg3);
  
  	case KEYCTL_DH_COMPUTE:
  		return compat_keyctl_dh_compute(compat_ptr(arg2),
  						compat_ptr(arg3),
  						arg4, compat_ptr(arg5));
  
  	case KEYCTL_RESTRICT_KEYRING:
  		return keyctl_restrict_keyring(arg2, compat_ptr(arg3),
  					       compat_ptr(arg4));
  
  	case KEYCTL_PKEY_QUERY:
  		if (arg3 != 0)
  			return -EINVAL;
  		return keyctl_pkey_query(arg2,
  					 compat_ptr(arg4),
  					 compat_ptr(arg5));
  
  	case KEYCTL_PKEY_ENCRYPT:
  	case KEYCTL_PKEY_DECRYPT:
  	case KEYCTL_PKEY_SIGN:
  		return keyctl_pkey_e_d_s(option,
  					 compat_ptr(arg2), compat_ptr(arg3),
  					 compat_ptr(arg4), compat_ptr(arg5));
  
  	case KEYCTL_PKEY_VERIFY:
  		return keyctl_pkey_verify(compat_ptr(arg2), compat_ptr(arg3),
  					  compat_ptr(arg4), compat_ptr(arg5));
  
  	default:
  		return -EOPNOTSUPP;
  	}
  }
  