1dbb60c8aSBenjamin Tissoires // SPDX-License-Identifier: GPL-2.0
2dbb60c8aSBenjamin Tissoires /* Copyright (c) 2022 Red hat */
3dbb60c8aSBenjamin Tissoires #include "vmlinux.h"
4dbb60c8aSBenjamin Tissoires #include <bpf/bpf_helpers.h>
5dbb60c8aSBenjamin Tissoires #include <bpf/bpf_tracing.h>
6dbb60c8aSBenjamin Tissoires #include "hid_bpf_helpers.h"
7dbb60c8aSBenjamin Tissoires
8dbb60c8aSBenjamin Tissoires char _license[] SEC("license") = "GPL";
9dbb60c8aSBenjamin Tissoires
10dbb60c8aSBenjamin Tissoires struct attach_prog_args {
11dbb60c8aSBenjamin Tissoires int prog_fd;
12dbb60c8aSBenjamin Tissoires unsigned int hid;
13dbb60c8aSBenjamin Tissoires int retval;
1480e189f2SBenjamin Tissoires int insert_head;
15dbb60c8aSBenjamin Tissoires };
16dbb60c8aSBenjamin Tissoires
17dbb60c8aSBenjamin Tissoires __u64 callback_check = 52;
18dbb60c8aSBenjamin Tissoires __u64 callback2_check = 52;
19dbb60c8aSBenjamin Tissoires
20dbb60c8aSBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_first_event,struct hid_bpf_ctx * hid_ctx)21dbb60c8aSBenjamin Tissoires int BPF_PROG(hid_first_event, struct hid_bpf_ctx *hid_ctx)
22dbb60c8aSBenjamin Tissoires {
23dbb60c8aSBenjamin Tissoires __u8 *rw_data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 3 /* size */);
24dbb60c8aSBenjamin Tissoires
25dbb60c8aSBenjamin Tissoires if (!rw_data)
26dbb60c8aSBenjamin Tissoires return 0; /* EPERM check */
27dbb60c8aSBenjamin Tissoires
28dbb60c8aSBenjamin Tissoires callback_check = rw_data[1];
29dbb60c8aSBenjamin Tissoires
30dbb60c8aSBenjamin Tissoires rw_data[2] = rw_data[1] + 5;
31dbb60c8aSBenjamin Tissoires
320330f725SBenjamin Tissoires return hid_ctx->size;
330330f725SBenjamin Tissoires }
340330f725SBenjamin Tissoires
350330f725SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_second_event,struct hid_bpf_ctx * hid_ctx)36*cea6c4d9SBenjamin Tissoires int BPF_PROG(hid_second_event, struct hid_bpf_ctx *hid_ctx)
37*cea6c4d9SBenjamin Tissoires {
38*cea6c4d9SBenjamin Tissoires __u8 *rw_data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4 /* size */);
39*cea6c4d9SBenjamin Tissoires
40*cea6c4d9SBenjamin Tissoires if (!rw_data)
41*cea6c4d9SBenjamin Tissoires return 0; /* EPERM check */
42*cea6c4d9SBenjamin Tissoires
43*cea6c4d9SBenjamin Tissoires rw_data[3] = rw_data[2] + 5;
44*cea6c4d9SBenjamin Tissoires
45*cea6c4d9SBenjamin Tissoires return hid_ctx->size;
46*cea6c4d9SBenjamin Tissoires }
47*cea6c4d9SBenjamin Tissoires
48*cea6c4d9SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_change_report_id,struct hid_bpf_ctx * hid_ctx)490330f725SBenjamin Tissoires int BPF_PROG(hid_change_report_id, struct hid_bpf_ctx *hid_ctx)
500330f725SBenjamin Tissoires {
510330f725SBenjamin Tissoires __u8 *rw_data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 3 /* size */);
520330f725SBenjamin Tissoires
530330f725SBenjamin Tissoires if (!rw_data)
540330f725SBenjamin Tissoires return 0; /* EPERM check */
550330f725SBenjamin Tissoires
560330f725SBenjamin Tissoires rw_data[0] = 2;
570330f725SBenjamin Tissoires
580330f725SBenjamin Tissoires return 9;
59dbb60c8aSBenjamin Tissoires }
60dbb60c8aSBenjamin Tissoires
61dbb60c8aSBenjamin Tissoires SEC("syscall")
attach_prog(struct attach_prog_args * ctx)62dbb60c8aSBenjamin Tissoires int attach_prog(struct attach_prog_args *ctx)
63dbb60c8aSBenjamin Tissoires {
64dbb60c8aSBenjamin Tissoires ctx->retval = hid_bpf_attach_prog(ctx->hid,
65dbb60c8aSBenjamin Tissoires ctx->prog_fd,
6680e189f2SBenjamin Tissoires ctx->insert_head ? HID_BPF_FLAG_INSERT_HEAD :
6780e189f2SBenjamin Tissoires HID_BPF_FLAG_NONE);
68dbb60c8aSBenjamin Tissoires return 0;
69dbb60c8aSBenjamin Tissoires }
704f7153cfSBenjamin Tissoires
714f7153cfSBenjamin Tissoires struct hid_hw_request_syscall_args {
724f7153cfSBenjamin Tissoires /* data needs to come at offset 0 so we can use it in calls */
734f7153cfSBenjamin Tissoires __u8 data[10];
744f7153cfSBenjamin Tissoires unsigned int hid;
754f7153cfSBenjamin Tissoires int retval;
764f7153cfSBenjamin Tissoires size_t size;
774f7153cfSBenjamin Tissoires enum hid_report_type type;
784f7153cfSBenjamin Tissoires __u8 request_type;
794f7153cfSBenjamin Tissoires };
804f7153cfSBenjamin Tissoires
814f7153cfSBenjamin Tissoires SEC("syscall")
hid_user_raw_request(struct hid_hw_request_syscall_args * args)824f7153cfSBenjamin Tissoires int hid_user_raw_request(struct hid_hw_request_syscall_args *args)
834f7153cfSBenjamin Tissoires {
844f7153cfSBenjamin Tissoires struct hid_bpf_ctx *ctx;
854f7153cfSBenjamin Tissoires const size_t size = args->size;
864f7153cfSBenjamin Tissoires int i, ret = 0;
874f7153cfSBenjamin Tissoires
884f7153cfSBenjamin Tissoires if (size > sizeof(args->data))
894f7153cfSBenjamin Tissoires return -7; /* -E2BIG */
904f7153cfSBenjamin Tissoires
914f7153cfSBenjamin Tissoires ctx = hid_bpf_allocate_context(args->hid);
924f7153cfSBenjamin Tissoires if (!ctx)
934f7153cfSBenjamin Tissoires return -1; /* EPERM check */
944f7153cfSBenjamin Tissoires
954f7153cfSBenjamin Tissoires ret = hid_bpf_hw_request(ctx,
964f7153cfSBenjamin Tissoires args->data,
974f7153cfSBenjamin Tissoires size,
984f7153cfSBenjamin Tissoires args->type,
994f7153cfSBenjamin Tissoires args->request_type);
1004f7153cfSBenjamin Tissoires args->retval = ret;
1014f7153cfSBenjamin Tissoires
1024f7153cfSBenjamin Tissoires hid_bpf_release_context(ctx);
1034f7153cfSBenjamin Tissoires
1044f7153cfSBenjamin Tissoires return 0;
1054f7153cfSBenjamin Tissoires }
106e8445737SBenjamin Tissoires
107e8445737SBenjamin Tissoires static const __u8 rdesc[] = {
108e8445737SBenjamin Tissoires 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
109e8445737SBenjamin Tissoires 0x09, 0x32, /* USAGE (Z) */
110e8445737SBenjamin Tissoires 0x95, 0x01, /* REPORT_COUNT (1) */
111e8445737SBenjamin Tissoires 0x81, 0x06, /* INPUT (Data,Var,Rel) */
112e8445737SBenjamin Tissoires
113e8445737SBenjamin Tissoires 0x06, 0x00, 0xff, /* Usage Page (Vendor Defined Page 1) */
114e8445737SBenjamin Tissoires 0x19, 0x01, /* USAGE_MINIMUM (1) */
115e8445737SBenjamin Tissoires 0x29, 0x03, /* USAGE_MAXIMUM (3) */
116e8445737SBenjamin Tissoires 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
117e8445737SBenjamin Tissoires 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */
118e8445737SBenjamin Tissoires 0x95, 0x03, /* REPORT_COUNT (3) */
119e8445737SBenjamin Tissoires 0x75, 0x01, /* REPORT_SIZE (1) */
120e8445737SBenjamin Tissoires 0x91, 0x02, /* Output (Data,Var,Abs) */
121e8445737SBenjamin Tissoires 0x95, 0x01, /* REPORT_COUNT (1) */
122e8445737SBenjamin Tissoires 0x75, 0x05, /* REPORT_SIZE (5) */
123e8445737SBenjamin Tissoires 0x91, 0x01, /* Output (Cnst,Var,Abs) */
124e8445737SBenjamin Tissoires
125e8445737SBenjamin Tissoires 0x06, 0x00, 0xff, /* Usage Page (Vendor Defined Page 1) */
126e8445737SBenjamin Tissoires 0x19, 0x06, /* USAGE_MINIMUM (6) */
127e8445737SBenjamin Tissoires 0x29, 0x08, /* USAGE_MAXIMUM (8) */
128e8445737SBenjamin Tissoires 0x15, 0x00, /* LOGICAL_MINIMUM (0) */
129e8445737SBenjamin Tissoires 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */
130e8445737SBenjamin Tissoires 0x95, 0x03, /* REPORT_COUNT (3) */
131e8445737SBenjamin Tissoires 0x75, 0x01, /* REPORT_SIZE (1) */
132e8445737SBenjamin Tissoires 0xb1, 0x02, /* Feature (Data,Var,Abs) */
133e8445737SBenjamin Tissoires 0x95, 0x01, /* REPORT_COUNT (1) */
134e8445737SBenjamin Tissoires 0x75, 0x05, /* REPORT_SIZE (5) */
135e8445737SBenjamin Tissoires 0x91, 0x01, /* Output (Cnst,Var,Abs) */
136e8445737SBenjamin Tissoires
137e8445737SBenjamin Tissoires 0xc0, /* END_COLLECTION */
138e8445737SBenjamin Tissoires 0xc0, /* END_COLLECTION */
139e8445737SBenjamin Tissoires };
140e8445737SBenjamin Tissoires
141e8445737SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_rdesc_fixup")
BPF_PROG(hid_rdesc_fixup,struct hid_bpf_ctx * hid_ctx)142e8445737SBenjamin Tissoires int BPF_PROG(hid_rdesc_fixup, struct hid_bpf_ctx *hid_ctx)
143e8445737SBenjamin Tissoires {
144e8445737SBenjamin Tissoires __u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4096 /* size */);
145e8445737SBenjamin Tissoires
146e8445737SBenjamin Tissoires if (!data)
147e8445737SBenjamin Tissoires return 0; /* EPERM check */
148e8445737SBenjamin Tissoires
149e8445737SBenjamin Tissoires callback2_check = data[4];
150e8445737SBenjamin Tissoires
151e8445737SBenjamin Tissoires /* insert rdesc at offset 73 */
152e8445737SBenjamin Tissoires __builtin_memcpy(&data[73], rdesc, sizeof(rdesc));
153e8445737SBenjamin Tissoires
154e8445737SBenjamin Tissoires /* Change Usage Vendor globally */
155e8445737SBenjamin Tissoires data[4] = 0x42;
156e8445737SBenjamin Tissoires
157e8445737SBenjamin Tissoires return sizeof(rdesc) + 73;
158e8445737SBenjamin Tissoires }
15980e189f2SBenjamin Tissoires
16080e189f2SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_test_insert1,struct hid_bpf_ctx * hid_ctx)16180e189f2SBenjamin Tissoires int BPF_PROG(hid_test_insert1, struct hid_bpf_ctx *hid_ctx)
16280e189f2SBenjamin Tissoires {
16380e189f2SBenjamin Tissoires __u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4 /* size */);
16480e189f2SBenjamin Tissoires
16580e189f2SBenjamin Tissoires if (!data)
16680e189f2SBenjamin Tissoires return 0; /* EPERM check */
16780e189f2SBenjamin Tissoires
16880e189f2SBenjamin Tissoires /* we need to be run first */
16980e189f2SBenjamin Tissoires if (data[2] || data[3])
17080e189f2SBenjamin Tissoires return -1;
17180e189f2SBenjamin Tissoires
17280e189f2SBenjamin Tissoires data[1] = 1;
17380e189f2SBenjamin Tissoires
17480e189f2SBenjamin Tissoires return 0;
17580e189f2SBenjamin Tissoires }
17680e189f2SBenjamin Tissoires
17780e189f2SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_test_insert2,struct hid_bpf_ctx * hid_ctx)17880e189f2SBenjamin Tissoires int BPF_PROG(hid_test_insert2, struct hid_bpf_ctx *hid_ctx)
17980e189f2SBenjamin Tissoires {
18080e189f2SBenjamin Tissoires __u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4 /* size */);
18180e189f2SBenjamin Tissoires
18280e189f2SBenjamin Tissoires if (!data)
18380e189f2SBenjamin Tissoires return 0; /* EPERM check */
18480e189f2SBenjamin Tissoires
18580e189f2SBenjamin Tissoires /* after insert0 and before insert2 */
18680e189f2SBenjamin Tissoires if (!data[1] || data[3])
18780e189f2SBenjamin Tissoires return -1;
18880e189f2SBenjamin Tissoires
18980e189f2SBenjamin Tissoires data[2] = 2;
19080e189f2SBenjamin Tissoires
19180e189f2SBenjamin Tissoires return 0;
19280e189f2SBenjamin Tissoires }
19380e189f2SBenjamin Tissoires
19480e189f2SBenjamin Tissoires SEC("?fmod_ret/hid_bpf_device_event")
BPF_PROG(hid_test_insert3,struct hid_bpf_ctx * hid_ctx)19580e189f2SBenjamin Tissoires int BPF_PROG(hid_test_insert3, struct hid_bpf_ctx *hid_ctx)
19680e189f2SBenjamin Tissoires {
19780e189f2SBenjamin Tissoires __u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4 /* size */);
19880e189f2SBenjamin Tissoires
19980e189f2SBenjamin Tissoires if (!data)
20080e189f2SBenjamin Tissoires return 0; /* EPERM check */
20180e189f2SBenjamin Tissoires
20280e189f2SBenjamin Tissoires /* at the end */
20380e189f2SBenjamin Tissoires if (!data[1] || !data[2])
20480e189f2SBenjamin Tissoires return -1;
20580e189f2SBenjamin Tissoires
20680e189f2SBenjamin Tissoires data[3] = 3;
20780e189f2SBenjamin Tissoires
20880e189f2SBenjamin Tissoires return 0;
20980e189f2SBenjamin Tissoires }
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