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HID: add source argument to HID low level functions

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This allows to know who actually sent what when we process the request
to the device.
This will be useful for a BPF firewall program to allow or not requests
coming from a dedicated hidraw node client.

Link: https://patch.msgid.link/20240626-hid_hw_req_bpf-v2-2-cfd60fb6c79f@kernel.org
Acked-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
This commit is contained in:
Benjamin Tissoires 2024-06-26 15:46:23 +02:00
parent ebae0b2a6f
commit 67eccf151d
6 changed files with 87 additions and 54 deletions
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12
drivers/hid/bpf/hid_bpf_dispatch.c
View File

@ -24,7 +24,7 @@ EXPORT_SYMBOL(hid_ops);
u8 *
dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type, u8 *data,
u32 *size, int interrupt)
u32 *size, int interrupt, u64 source)
{
struct hid_bpf_ctx_kern ctx_kern = {
.ctx = {
@ -50,7 +50,7 @@ dispatch_hid_bpf_device_event(struct hid_device *hdev, enum hid_report_type type
rcu_read_lock();
list_for_each_entry_rcu(e, &hdev->bpf.prog_list, list) {
if (e->hid_device_event) {
ret = e->hid_device_event(&ctx_kern.ctx, type);
ret = e->hid_device_event(&ctx_kern.ctx, type, source);
if (ret < 0) {
rcu_read_unlock();
return ERR_PTR(ret);
@ -359,7 +359,8 @@ hid_bpf_hw_request(struct hid_bpf_ctx *ctx, __u8 *buf, size_t buf__sz,
dma_data,
size,
rtype,
reqtype);
reqtype,
(__u64)ctx);
if (ret > 0)
memcpy(buf, dma_data, ret);
@ -398,7 +399,8 @@ hid_bpf_hw_output_report(struct hid_bpf_ctx *ctx, __u8 *buf, size_t buf__sz)
ret = hid_ops->hid_hw_output_report(hdev,
dma_data,
size);
size,
(__u64)ctx);
kfree(dma_data);
return ret;
@ -429,7 +431,7 @@ hid_bpf_input_report(struct hid_bpf_ctx *ctx, enum hid_report_type type, u8 *buf
hdev = (struct hid_device *)ctx->hid; /* discard const */
return hid_ops->hid_input_report(hdev, type, buf, size, 0);
return hid_ops->hid_input_report(hdev, type, buf, size, 0, (__u64)ctx);
}
__bpf_kfunc_end_defs();

2
drivers/hid/bpf/hid_bpf_struct_ops.c
View File

@ -257,7 +257,7 @@ static void hid_bpf_unreg(void *kdata)
hid_put_device(hdev);
}
static int __hid_bpf_device_event(struct hid_bpf_ctx *ctx, enum hid_report_type type)
static int __hid_bpf_device_event(struct hid_bpf_ctx *ctx, enum hid_report_type type, __u64 source)
{
return 0;
}

95
drivers/hid/hid-core.c
View File

@ -2025,19 +2025,9 @@ out:
}
EXPORT_SYMBOL_GPL(hid_report_raw_event);
/**
* hid_input_report - report data from lower layer (usb, bt...)
*
* @hid: hid device
* @type: HID report type (HID_*_REPORT)
* @data: report contents
* @size: size of data parameter
* @interrupt: distinguish between interrupt and control transfers
*
* This is data entry for lower layers.
*/
int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
int interrupt)
static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
u8 *data, u32 size, int interrupt, u64 source)
{
struct hid_report_enum *report_enum;
struct hid_driver *hdrv;
@ -2057,7 +2047,7 @@ int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data
report_enum = hid->report_enum + type;
hdrv = hid->driver;
data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt);
data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt, source);
if (IS_ERR(data)) {
ret = PTR_ERR(data);
goto unlock;
@ -2092,6 +2082,23 @@ unlock:
up(&hid->driver_input_lock);
return ret;
}
/**
* hid_input_report - report data from lower layer (usb, bt...)
*
* @hid: hid device
* @type: HID report type (HID_*_REPORT)
* @data: report contents
* @size: size of data parameter
* @interrupt: distinguish between interrupt and control transfers
*
* This is data entry for lower layers.
*/
int hid_input_report(struct hid_device *hid, enum hid_report_type type, u8 *data, u32 size,
int interrupt)
{
return __hid_input_report(hid, type, data, size, interrupt, 0);
}
EXPORT_SYMBOL_GPL(hid_input_report);
bool hid_match_one_id(const struct hid_device *hdev,
@ -2392,6 +2399,24 @@ void hid_hw_request(struct hid_device *hdev,
}
EXPORT_SYMBOL_GPL(hid_hw_request);
int __hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype,
enum hid_class_request reqtype,
__u64 source)
{
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
if (hdev->ll_driver->max_buffer_size)
max_buffer_size = hdev->ll_driver->max_buffer_size;
if (len < 1 || len > max_buffer_size || !buf)
return -EINVAL;
return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
rtype, reqtype);
}
/**
* hid_hw_raw_request - send report request to device
*
@ -2410,29 +2435,11 @@ int hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype, enum hid_class_request reqtype)
{
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
if (hdev->ll_driver->max_buffer_size)
max_buffer_size = hdev->ll_driver->max_buffer_size;
if (len < 1 || len > max_buffer_size || !buf)
return -EINVAL;
return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
rtype, reqtype);
return __hid_hw_raw_request(hdev, reportnum, buf, len, rtype, reqtype, 0);
}
EXPORT_SYMBOL_GPL(hid_hw_raw_request);
/**
* hid_hw_output_report - send output report to device
*
* @hdev: hid device
* @buf: raw data to transfer
* @len: length of buf
*
* Return: count of data transferred, negative if error
*/
int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
int __hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len, __u64 source)
{
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
@ -2447,6 +2454,20 @@ int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
return -ENOSYS;
}
/**
* hid_hw_output_report - send output report to device
*
* @hdev: hid device
* @buf: raw data to transfer
* @len: length of buf
*
* Return: count of data transferred, negative if error
*/
int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
{
return __hid_hw_output_report(hdev, buf, len, 0);
}
EXPORT_SYMBOL_GPL(hid_hw_output_report);
#ifdef CONFIG_PM
@ -2972,9 +2993,9 @@ EXPORT_SYMBOL_GPL(hid_check_keys_pressed);
#ifdef CONFIG_HID_BPF
static struct hid_ops __hid_ops = {
.hid_get_report = hid_get_report,
.hid_hw_raw_request = hid_hw_raw_request,
.hid_hw_output_report = hid_hw_output_report,
.hid_input_report = hid_input_report,
.hid_hw_raw_request = __hid_hw_raw_request,
.hid_hw_output_report = __hid_hw_output_report,
.hid_input_report = __hid_input_report,
.owner = THIS_MODULE,
.bus_type = &hid_bus_type,
};

10
drivers/hid/hidraw.c
View File

@ -140,7 +140,7 @@ static ssize_t hidraw_send_report(struct file *file, const char __user *buffer,
if ((report_type == HID_OUTPUT_REPORT) &&
!(dev->quirks & HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP)) {
ret = hid_hw_output_report(dev, buf, count);
ret = __hid_hw_output_report(dev, buf, count, (__u64)file);
/*
* compatibility with old implementation of USB-HID and I2C-HID:
* if the device does not support receiving output reports,
@ -150,8 +150,8 @@ static ssize_t hidraw_send_report(struct file *file, const char __user *buffer,
goto out_free;
}
ret = hid_hw_raw_request(dev, buf[0], buf, count, report_type,
HID_REQ_SET_REPORT);
ret = __hid_hw_raw_request(dev, buf[0], buf, count, report_type,
HID_REQ_SET_REPORT, (__u64)file);
out_free:
kfree(buf);
@ -227,8 +227,8 @@ static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t
goto out_free;
}
ret = hid_hw_raw_request(dev, report_number, buf, count, report_type,
HID_REQ_GET_REPORT);
ret = __hid_hw_raw_request(dev, report_number, buf, count, report_type,
HID_REQ_GET_REPORT, (__u64)file);
if (ret < 0)
goto out_free;

6
include/linux/hid.h
View File

@ -1125,6 +1125,12 @@ int __must_check hid_hw_open(struct hid_device *hdev);
void hid_hw_close(struct hid_device *hdev);
void hid_hw_request(struct hid_device *hdev,
struct hid_report *report, enum hid_class_request reqtype);
int __hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype,
enum hid_class_request reqtype,
__u64 source);
int __hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len, __u64 source);
int hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype,

16
include/linux/hid_bpf.h
View File

@ -66,10 +66,12 @@ struct hid_ops {
int (*hid_hw_raw_request)(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype,
enum hid_class_request reqtype);
int (*hid_hw_output_report)(struct hid_device *hdev, __u8 *buf, size_t len);
enum hid_class_request reqtype,
__u64 source);
int (*hid_hw_output_report)(struct hid_device *hdev, __u8 *buf, size_t len,
__u64 source);
int (*hid_input_report)(struct hid_device *hid, enum hid_report_type type,
u8 *data, u32 size, int interrupt);
u8 *data, u32 size, int interrupt, u64 source);
struct module *owner;
const struct bus_type *bus_type;
};
@ -110,7 +112,8 @@ struct hid_bpf_ops {
*
* Context: Interrupt context.
*/
int (*hid_device_event)(struct hid_bpf_ctx *ctx, enum hid_report_type report_type);
int (*hid_device_event)(struct hid_bpf_ctx *ctx, enum hid_report_type report_type,
__u64 source);
/**
* @hid_rdesc_fixup: called when the probe function parses the report descriptor
@ -146,7 +149,7 @@ struct hid_bpf {
#ifdef CONFIG_HID_BPF
u8 *dispatch_hid_bpf_device_event(struct hid_device *hid, enum hid_report_type type, u8 *data,
u32 *size, int interrupt);
u32 *size, int interrupt, u64 source);
int hid_bpf_connect_device(struct hid_device *hdev);
void hid_bpf_disconnect_device(struct hid_device *hdev);
void hid_bpf_destroy_device(struct hid_device *hid);
@ -154,7 +157,8 @@ void hid_bpf_device_init(struct hid_device *hid);
u8 *call_hid_bpf_rdesc_fixup(struct hid_device *hdev, u8 *rdesc, unsigned int *size);
#else /* CONFIG_HID_BPF */
static inline u8 *dispatch_hid_bpf_device_event(struct hid_device *hid, enum hid_report_type type,
u8 *data, u32 *size, int interrupt) { return data; }
u8 *data, u32 *size, int interrupt,
u64 source) { return data; }
static inline int hid_bpf_connect_device(struct hid_device *hdev) { return 0; }
static inline void hid_bpf_disconnect_device(struct hid_device *hdev) {}
static inline void hid_bpf_destroy_device(struct hid_device *hid) {}