text: /*
   * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
   * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
   * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
   * Copyright (c) 1996-2001 Wichert Akkerman <wichert@cistron.nl>
   * Copyright (c) 1999-2018 The strace developers.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "defs.h"
  #include <linux/ioctl.h>
  #include "xlat/ioctl_dirs.h"
  
  static int
  compare(const void *a, const void *b)
  {
  	const unsigned int code1 = (const uintptr_t) a;
  	const unsigned int code2 = ((struct_ioctlent *) b)->code;
  	return (code1 > code2) ? 1 : (code1 < code2) ? -1 : 0;
  }
  
  static const struct_ioctlent *
  ioctl_lookup(const unsigned int code)
  {
  	struct_ioctlent *iop;
  
  	iop = bsearch((const void *) (const uintptr_t) code, ioctlent,
  			nioctlents, sizeof(ioctlent[0]), compare);
  	while (iop > ioctlent) {
  		iop--;
  		if (iop->code != code) {
  			iop++;
  			break;
  		}
  	}
  	return iop;
  }
  
  static const struct_ioctlent *
  ioctl_next_match(const struct_ioctlent *iop)
  {
  	const unsigned int code = iop->code;
  	iop++;
  	if (iop < ioctlent + nioctlents && iop->code == code)
  		return iop;
  	return NULL;
  }
  
  static void
  ioctl_print_code(const unsigned int code)
  {
  	tprints("_IOC(");
  	printflags(ioctl_dirs, _IOC_DIR(code), "_IOC_???");
  	tprintf(", %#x, %#x, %#x)",
  		_IOC_TYPE(code), _IOC_NR(code), _IOC_SIZE(code));
  }
  
  static int
  evdev_decode_number(const unsigned int code)
  {
  	const unsigned int nr = _IOC_NR(code);
  
  	if (_IOC_DIR(code) == _IOC_WRITE) {
  		if (nr >= 0xc0 && nr <= 0xc0 + 0x3f) {
  			tprints("EVIOCSABS(");
  			printxval_indexn(evdev_abs, evdev_abs_size, nr - 0xc0,
  					 "ABS_???");
  			tprints(")");
  			return 1;
  		}
  	}
  
  	if (_IOC_DIR(code) != _IOC_READ)
  		return 0;
  
  	if (nr >= 0x20 && nr <= 0x20 + 0x1f) {
  		tprints("EVIOCGBIT(");
  		if (nr == 0x20)
  			tprintf("0");
  		else
  			printxval(evdev_ev, nr - 0x20, "EV_???");
  		tprintf(", %u)", _IOC_SIZE(code));
  		return 1;
  	} else if (nr >= 0x40 && nr <= 0x40 + 0x3f) {
  		tprints("EVIOCGABS(");
  		printxval_indexn(evdev_abs, evdev_abs_size, nr - 0x40,
  				 "ABS_???");
  		tprints(")");
  		return 1;
  	}
  
  	switch (_IOC_NR(nr)) {
  		case 0x06:
  			tprintf("EVIOCGNAME(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x07:
  			tprintf("EVIOCGPHYS(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x08:
  			tprintf("EVIOCGUNIQ(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x09:
  			tprintf("EVIOCGPROP(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x0a:
  			tprintf("EVIOCGMTSLOTS(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x18:
  			tprintf("EVIOCGKEY(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x19:
  			tprintf("EVIOCGLED(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x1a:
  			tprintf("EVIOCGSND(%u)", _IOC_SIZE(code));
  			return 1;
  		case 0x1b:
  			tprintf("EVIOCGSW(%u)", _IOC_SIZE(code));
  			return 1;
  		default:
  			return 0;
  	}
  }
  
  static int
  hiddev_decode_number(const unsigned int code)
  {
  	if (_IOC_DIR(code) == _IOC_READ) {
  		switch (_IOC_NR(code)) {
  			case 0x04:
  				tprintf("HIDIOCGRAWNAME(%u)", _IOC_SIZE(code));
  				return 1;
  			case 0x05:
  				tprintf("HIDIOCGRAWPHYS(%u)", _IOC_SIZE(code));
  				return 1;
  			case 0x06:
  				tprintf("HIDIOCSFEATURE(%u)", _IOC_SIZE(code));
  				return 1;
  			case 0x12:
  				tprintf("HIDIOCGPHYS(%u)", _IOC_SIZE(code));
  				return 1;
  			default:
  				return 0;
  		}
  	} else if (_IOC_DIR(code) == (_IOC_READ | _IOC_WRITE)) {
  		switch (_IOC_NR(code)) {
  			case 0x06:
  				tprintf("HIDIOCSFEATURE(%u)", _IOC_SIZE(code));
  				return 1;
  			case 0x07:
  				tprintf("HIDIOCGFEATURE(%u)", _IOC_SIZE(code));
  				return 1;
  			default:
  				return 0;
  		}
  	}
  
  	return 0;
  }
  
  static int
  ioctl_decode_command_number(struct tcb *tcp)
  {
  	const unsigned int code = tcp->u_arg[1];
  
  	switch (_IOC_TYPE(code)) {
  		case 'E':
  			return evdev_decode_number(code);
  		case 'H':
  			return hiddev_decode_number(code);
  		case 'M':
  			if (_IOC_DIR(code) == _IOC_WRITE) {
  				tprintf("MIXER_WRITE(%u)", _IOC_NR(code));
  				return 1;
  			} else if (_IOC_DIR(code) == _IOC_READ) {
  				tprintf("MIXER_READ(%u)", _IOC_NR(code));
  				return 1;
  			}
  			return 0;
  		case 'U':
  			if (_IOC_DIR(code) == _IOC_READ && _IOC_NR(code) == 0x2c) {
  				tprintf("UI_GET_SYSNAME(%u)", _IOC_SIZE(code));
  				return 1;
  			}
  			return 0;
  		case 'j':
  			if (_IOC_DIR(code) == _IOC_READ && _IOC_NR(code) == 0x13) {
  				tprintf("JSIOCGNAME(%u)", _IOC_SIZE(code));
  				return 1;
  			}
  			return 0;
  		case 'k':
  			if (_IOC_DIR(code) == _IOC_WRITE && _IOC_NR(code) == 0) {
  				tprintf("SPI_IOC_MESSAGE(%u)", _IOC_SIZE(code));
  				return 1;
  			}
  			return 0;
  		default:
  			return 0;
  	}
  }
  
  /**
   * Decode arg parameter of the ioctl call.
   *
   * @return There are two flags of the return value important for the purposes of
   *         processing by SYS_FUNC(ioctl):
   *          - RVAL_IOCTL_DECODED: indicates that ioctl decoder code
   *                                has printed arg parameter;
   *          - RVAL_DECODED: indicates that decoding is done.
   *         As a result, the following behaviour is expected:
   *          - on entering:
   *            - 0: decoding should be continued on exiting;
   *            - RVAL_IOCTL_DECODED: decoding on exiting is not needed
   *                                  and decoder has printed arg value;
   *            - RVAL_DECODED: decoding on exiting is not needed
   *                            and generic handler should print arg value.
   *          - on exiting:
   *            - 0: generic handler should print arg value;
   *            - RVAL_IOCTL_DECODED: decoder has printed arg value.
   *
   *         Note that it makes no sense to return just RVAL_DECODED on exiting,
   *         but, of course, it is not prohibited (for example, it may be useful
   *         in cases where the return path is common on entering and on exiting
   *         the syscall).
   *
   *         SYS_FUNC(ioctl) converts RVAL_IOCTL_DECODED flag to RVAL_DECODED,
   *         and passes all other bits of ioctl_decode return value unchanged.
   */
  static int
  ioctl_decode(struct tcb *tcp)
  {
  	const unsigned int code = tcp->u_arg[1];
  	const kernel_ulong_t arg = tcp->u_arg[2];
  
  	switch (_IOC_TYPE(code)) {
  	case '$':
  		return perf_ioctl(tcp, code, arg);
  #if defined(ALPHA) || defined(POWERPC)
  	case 'f': {
  		int ret = file_ioctl(tcp, code, arg);
  		if (ret != RVAL_DECODED)
  			return ret;
  		ATTRIBUTE_FALLTHROUGH;
  	}
  	case 't':
  	case 'T':
  		return term_ioctl(tcp, code, arg);
  #else /* !ALPHA */
  	case 'f':
  		return file_ioctl(tcp, code, arg);
  	case 0x54:
  #endif /* !ALPHA */
  		return term_ioctl(tcp, code, arg);
  	case 0x89:
  		return sock_ioctl(tcp, code, arg);
  	case 'p':
  		return rtc_ioctl(tcp, code, arg);
  	case 0x03:
  		return hdio_ioctl(tcp, code, arg);
  	case 0x12:
  		return block_ioctl(tcp, code, arg);
  	case 'X':
  		return fs_x_ioctl(tcp, code, arg);
  	case 0x22:
  		return scsi_ioctl(tcp, code, arg);
  	case 'L':
  		return loop_ioctl(tcp, code, arg);
  #ifdef HAVE_STRUCT_MTD_WRITE_REQ
  	case 'M':
  		return mtd_ioctl(tcp, code, arg);
  #endif
  #ifdef HAVE_STRUCT_UBI_ATTACH_REQ_MAX_BEB_PER1024
  	case 'o':
  	case 'O':
  		return ubi_ioctl(tcp, code, arg);
  #endif
  	case 'V':
  		return v4l2_ioctl(tcp, code, arg);
  #ifdef HAVE_STRUCT_PTP_SYS_OFFSET
  	case '=':
  		return ptp_ioctl(tcp, code, arg);
  #endif
  #ifdef HAVE_LINUX_INPUT_H
  	case 'E':
  		return evdev_ioctl(tcp, code, arg);
  #endif
  #ifdef HAVE_LINUX_USERFAULTFD_H
  	case 0xaa:
  		return uffdio_ioctl(tcp, code, arg);
  #endif
  #ifdef HAVE_LINUX_BTRFS_H
  	case 0x94:
  		return btrfs_ioctl(tcp, code, arg);
  #endif
  	case 0xb7:
  		return nsfs_ioctl(tcp, code, arg);
  #ifdef HAVE_LINUX_DM_IOCTL_H
  	case 0xfd:
  		return dm_ioctl(tcp, code, arg);
  #endif
  #ifdef HAVE_LINUX_KVM_H
  	case 0xae:
  		return kvm_ioctl(tcp, code, arg);
  #endif
  	case 'I':
  		return inotify_ioctl(tcp, code, arg);
  	default:
  		break;
  	}
  	return 0;
  }
  
  SYS_FUNC(ioctl)
  {
  	const struct_ioctlent *iop;
  	int ret;
  
  	if (entering(tcp)) {
  		printfd(tcp, tcp->u_arg[0]);
  		tprints(", ");
  
  		if (xlat_verbosity != XLAT_STYLE_ABBREV)
  			tprintf("%#x", (unsigned int) tcp->u_arg[1]);
  		if (xlat_verbosity == XLAT_STYLE_VERBOSE)
  			tprints(" /* ");
  		if (xlat_verbosity != XLAT_STYLE_RAW) {
  			ret = ioctl_decode_command_number(tcp);
  			if (!(ret & IOCTL_NUMBER_STOP_LOOKUP)) {
  				iop = ioctl_lookup(tcp->u_arg[1]);
  				if (iop) {
  					if (ret)
  						tprints(" or ");
  					tprints(iop->symbol);
  					while ((iop = ioctl_next_match(iop)))
  						tprintf(" or %s", iop->symbol);
  				} else if (!ret) {
  					ioctl_print_code(tcp->u_arg[1]);
  				}
  			}
  		}
  		if (xlat_verbosity == XLAT_STYLE_VERBOSE)
  			tprints(" */");
  
  		ret = ioctl_decode(tcp);
  	} else {
  		ret = ioctl_decode(tcp) | RVAL_DECODED;
  	}
  
  	if (ret & RVAL_IOCTL_DECODED) {
  		ret &= ~RVAL_IOCTL_DECODED;
  		ret |= RVAL_DECODED;
  	} else if (ret & RVAL_DECODED) {
  		tprintf(", %#" PRI_klx, tcp->u_arg[2]);
  	}
  
  	return ret;
  }
  