1// Copyright 2021 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package unix
6
7import (
8	"unsafe"
9)
10
11// IoctlRetInt performs an ioctl operation specified by req on a device
12// associated with opened file descriptor fd, and returns a non-negative
13// integer that is returned by the ioctl syscall.
14func IoctlRetInt(fd int, req uint) (int, error) {
15	ret, _, err := Syscall(SYS_IOCTL, uintptr(fd), uintptr(req), 0)
16	if err != 0 {
17		return 0, err
18	}
19	return int(ret), nil
20}
21
22func IoctlGetUint32(fd int, req uint) (uint32, error) {
23	var value uint32
24	err := ioctlPtr(fd, req, unsafe.Pointer(&value))
25	return value, err
26}
27
28func IoctlGetRTCTime(fd int) (*RTCTime, error) {
29	var value RTCTime
30	err := ioctlPtr(fd, RTC_RD_TIME, unsafe.Pointer(&value))
31	return &value, err
32}
33
34func IoctlSetRTCTime(fd int, value *RTCTime) error {
35	return ioctlPtr(fd, RTC_SET_TIME, unsafe.Pointer(value))
36}
37
38func IoctlGetRTCWkAlrm(fd int) (*RTCWkAlrm, error) {
39	var value RTCWkAlrm
40	err := ioctlPtr(fd, RTC_WKALM_RD, unsafe.Pointer(&value))
41	return &value, err
42}
43
44func IoctlSetRTCWkAlrm(fd int, value *RTCWkAlrm) error {
45	return ioctlPtr(fd, RTC_WKALM_SET, unsafe.Pointer(value))
46}
47
48// IoctlGetEthtoolDrvinfo fetches ethtool driver information for the network
49// device specified by ifname.
50func IoctlGetEthtoolDrvinfo(fd int, ifname string) (*EthtoolDrvinfo, error) {
51	ifr, err := NewIfreq(ifname)
52	if err != nil {
53		return nil, err
54	}
55
56	value := EthtoolDrvinfo{Cmd: ETHTOOL_GDRVINFO}
57	ifrd := ifr.withData(unsafe.Pointer(&value))
58
59	err = ioctlIfreqData(fd, SIOCETHTOOL, &ifrd)
60	return &value, err
61}
62
63// IoctlGetWatchdogInfo fetches information about a watchdog device from the
64// Linux watchdog API. For more information, see:
65// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
66func IoctlGetWatchdogInfo(fd int) (*WatchdogInfo, error) {
67	var value WatchdogInfo
68	err := ioctlPtr(fd, WDIOC_GETSUPPORT, unsafe.Pointer(&value))
69	return &value, err
70}
71
72// IoctlWatchdogKeepalive issues a keepalive ioctl to a watchdog device. For
73// more information, see:
74// https://www.kernel.org/doc/html/latest/watchdog/watchdog-api.html.
75func IoctlWatchdogKeepalive(fd int) error {
76	// arg is ignored and not a pointer, so ioctl is fine instead of ioctlPtr.
77	return ioctl(fd, WDIOC_KEEPALIVE, 0)
78}
79
80// IoctlFileCloneRange performs an FICLONERANGE ioctl operation to clone the
81// range of data conveyed in value to the file associated with the file
82// descriptor destFd. See the ioctl_ficlonerange(2) man page for details.
83func IoctlFileCloneRange(destFd int, value *FileCloneRange) error {
84	return ioctlPtr(destFd, FICLONERANGE, unsafe.Pointer(value))
85}
86
87// IoctlFileClone performs an FICLONE ioctl operation to clone the entire file
88// associated with the file description srcFd to the file associated with the
89// file descriptor destFd. See the ioctl_ficlone(2) man page for details.
90func IoctlFileClone(destFd, srcFd int) error {
91	return ioctl(destFd, FICLONE, uintptr(srcFd))
92}
93
94type FileDedupeRange struct {
95	Src_offset uint64
96	Src_length uint64
97	Reserved1  uint16
98	Reserved2  uint32
99	Info       []FileDedupeRangeInfo
100}
101
102type FileDedupeRangeInfo struct {
103	Dest_fd       int64
104	Dest_offset   uint64
105	Bytes_deduped uint64
106	Status        int32
107	Reserved      uint32
108}
109
110// IoctlFileDedupeRange performs an FIDEDUPERANGE ioctl operation to share the
111// range of data conveyed in value from the file associated with the file
112// descriptor srcFd to the value.Info destinations. See the
113// ioctl_fideduperange(2) man page for details.
114func IoctlFileDedupeRange(srcFd int, value *FileDedupeRange) error {
115	buf := make([]byte, SizeofRawFileDedupeRange+
116		len(value.Info)*SizeofRawFileDedupeRangeInfo)
117	rawrange := (*RawFileDedupeRange)(unsafe.Pointer(&buf[0]))
118	rawrange.Src_offset = value.Src_offset
119	rawrange.Src_length = value.Src_length
120	rawrange.Dest_count = uint16(len(value.Info))
121	rawrange.Reserved1 = value.Reserved1
122	rawrange.Reserved2 = value.Reserved2
123
124	for i := range value.Info {
125		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
126			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
127				uintptr(i*SizeofRawFileDedupeRangeInfo)))
128		rawinfo.Dest_fd = value.Info[i].Dest_fd
129		rawinfo.Dest_offset = value.Info[i].Dest_offset
130		rawinfo.Bytes_deduped = value.Info[i].Bytes_deduped
131		rawinfo.Status = value.Info[i].Status
132		rawinfo.Reserved = value.Info[i].Reserved
133	}
134
135	err := ioctlPtr(srcFd, FIDEDUPERANGE, unsafe.Pointer(&buf[0]))
136
137	// Output
138	for i := range value.Info {
139		rawinfo := (*RawFileDedupeRangeInfo)(unsafe.Pointer(
140			uintptr(unsafe.Pointer(&buf[0])) + uintptr(SizeofRawFileDedupeRange) +
141				uintptr(i*SizeofRawFileDedupeRangeInfo)))
142		value.Info[i].Dest_fd = rawinfo.Dest_fd
143		value.Info[i].Dest_offset = rawinfo.Dest_offset
144		value.Info[i].Bytes_deduped = rawinfo.Bytes_deduped
145		value.Info[i].Status = rawinfo.Status
146		value.Info[i].Reserved = rawinfo.Reserved
147	}
148
149	return err
150}
151
152func IoctlHIDGetDesc(fd int, value *HIDRawReportDescriptor) error {
153	return ioctlPtr(fd, HIDIOCGRDESC, unsafe.Pointer(value))
154}
155
156func IoctlHIDGetRawInfo(fd int) (*HIDRawDevInfo, error) {
157	var value HIDRawDevInfo
158	err := ioctlPtr(fd, HIDIOCGRAWINFO, unsafe.Pointer(&value))
159	return &value, err
160}
161
162func IoctlHIDGetRawName(fd int) (string, error) {
163	var value [_HIDIOCGRAWNAME_LEN]byte
164	err := ioctlPtr(fd, _HIDIOCGRAWNAME, unsafe.Pointer(&value[0]))
165	return ByteSliceToString(value[:]), err
166}
167
168func IoctlHIDGetRawPhys(fd int) (string, error) {
169	var value [_HIDIOCGRAWPHYS_LEN]byte
170	err := ioctlPtr(fd, _HIDIOCGRAWPHYS, unsafe.Pointer(&value[0]))
171	return ByteSliceToString(value[:]), err
172}
173
174func IoctlHIDGetRawUniq(fd int) (string, error) {
175	var value [_HIDIOCGRAWUNIQ_LEN]byte
176	err := ioctlPtr(fd, _HIDIOCGRAWUNIQ, unsafe.Pointer(&value[0]))
177	return ByteSliceToString(value[:]), err
178}
179
180// IoctlIfreq performs an ioctl using an Ifreq structure for input and/or
181// output. See the netdevice(7) man page for details.
182func IoctlIfreq(fd int, req uint, value *Ifreq) error {
183	// It is possible we will add more fields to *Ifreq itself later to prevent
184	// misuse, so pass the raw *ifreq directly.
185	return ioctlPtr(fd, req, unsafe.Pointer(&value.raw))
186}
187
188// TODO(mdlayher): export if and when IfreqData is exported.
189
190// ioctlIfreqData performs an ioctl using an ifreqData structure for input
191// and/or output. See the netdevice(7) man page for details.
192func ioctlIfreqData(fd int, req uint, value *ifreqData) error {
193	// The memory layout of IfreqData (type-safe) and ifreq (not type-safe) are
194	// identical so pass *IfreqData directly.
195	return ioctlPtr(fd, req, unsafe.Pointer(value))
196}
197