1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* Copyright (c) 2022 Benjamin Tissoires 3 */ 4 5 #ifndef __HID_BPF_HELPERS_H 6 #define __HID_BPF_HELPERS_H 7 8 /* "undefine" structs and enums in vmlinux.h, because we "override" them below */ 9 #define bpf_wq bpf_wq___not_used 10 #define hid_bpf_ctx hid_bpf_ctx___not_used 11 #define hid_bpf_ops hid_bpf_ops___not_used 12 #define hid_device hid_device___not_used 13 #define hid_report_type hid_report_type___not_used 14 #define hid_class_request hid_class_request___not_used 15 #define hid_bpf_attach_flags hid_bpf_attach_flags___not_used 16 #define HID_INPUT_REPORT HID_INPUT_REPORT___not_used 17 #define HID_OUTPUT_REPORT HID_OUTPUT_REPORT___not_used 18 #define HID_FEATURE_REPORT HID_FEATURE_REPORT___not_used 19 #define HID_REPORT_TYPES HID_REPORT_TYPES___not_used 20 #define HID_REQ_GET_REPORT HID_REQ_GET_REPORT___not_used 21 #define HID_REQ_GET_IDLE HID_REQ_GET_IDLE___not_used 22 #define HID_REQ_GET_PROTOCOL HID_REQ_GET_PROTOCOL___not_used 23 #define HID_REQ_SET_REPORT HID_REQ_SET_REPORT___not_used 24 #define HID_REQ_SET_IDLE HID_REQ_SET_IDLE___not_used 25 #define HID_REQ_SET_PROTOCOL HID_REQ_SET_PROTOCOL___not_used 26 27 /* do not define kfunc through vmlinux.h as this messes up our custom hack */ 28 #define BPF_NO_KFUNC_PROTOTYPES 29 30 #include "vmlinux.h" 31 32 #undef bpf_wq 33 #undef hid_bpf_ctx 34 #undef hid_bpf_ops 35 #undef hid_device 36 #undef hid_report_type 37 #undef hid_class_request 38 #undef hid_bpf_attach_flags 39 #undef HID_INPUT_REPORT 40 #undef HID_OUTPUT_REPORT 41 #undef HID_FEATURE_REPORT 42 #undef HID_REPORT_TYPES 43 #undef HID_REQ_GET_REPORT 44 #undef HID_REQ_GET_IDLE 45 #undef HID_REQ_GET_PROTOCOL 46 #undef HID_REQ_SET_REPORT 47 #undef HID_REQ_SET_IDLE 48 #undef HID_REQ_SET_PROTOCOL 49 50 #include <bpf/bpf_helpers.h> 51 #include <bpf/bpf_tracing.h> 52 #include <linux/const.h> 53 54 enum hid_report_type { 55 HID_INPUT_REPORT = 0, 56 HID_OUTPUT_REPORT = 1, 57 HID_FEATURE_REPORT = 2, 58 59 HID_REPORT_TYPES, 60 }; 61 62 struct hid_device { 63 unsigned int id; 64 } __attribute__((preserve_access_index)); 65 66 struct bpf_wq { 67 __u64 __opaque[2]; 68 }; 69 70 struct hid_bpf_ctx { 71 struct hid_device *hid; 72 __u32 allocated_size; 73 union { 74 __s32 retval; 75 __s32 size; 76 }; 77 } __attribute__((preserve_access_index)); 78 79 enum hid_class_request { 80 HID_REQ_GET_REPORT = 0x01, 81 HID_REQ_GET_IDLE = 0x02, 82 HID_REQ_GET_PROTOCOL = 0x03, 83 HID_REQ_SET_REPORT = 0x09, 84 HID_REQ_SET_IDLE = 0x0A, 85 HID_REQ_SET_PROTOCOL = 0x0B, 86 }; 87 88 struct hid_bpf_ops { 89 int hid_id; 90 u32 flags; 91 struct list_head list; 92 int (*hid_device_event)(struct hid_bpf_ctx *ctx, enum hid_report_type report_type, 93 u64 source); 94 int (*hid_rdesc_fixup)(struct hid_bpf_ctx *ctx); 95 int (*hid_hw_request)(struct hid_bpf_ctx *ctx, unsigned char reportnum, 96 enum hid_report_type rtype, enum hid_class_request reqtype, 97 u64 source); 98 int (*hid_hw_output_report)(struct hid_bpf_ctx *ctx, u64 source); 99 struct hid_device *hdev; 100 }; 101 102 #ifndef BPF_F_BEFORE 103 #define BPF_F_BEFORE (1U << 3) 104 #endif 105 106 /* following are kfuncs exported by HID for HID-BPF */ 107 extern __u8 *hid_bpf_get_data(struct hid_bpf_ctx *ctx, 108 unsigned int offset, 109 const size_t __sz) __weak __ksym; 110 extern struct hid_bpf_ctx *hid_bpf_allocate_context(unsigned int hid_id) __weak __ksym; 111 extern void hid_bpf_release_context(struct hid_bpf_ctx *ctx) __weak __ksym; 112 extern int hid_bpf_hw_request(struct hid_bpf_ctx *ctx, 113 __u8 *data, 114 size_t buf__sz, 115 enum hid_report_type type, 116 enum hid_class_request reqtype) __weak __ksym; 117 extern int hid_bpf_hw_output_report(struct hid_bpf_ctx *ctx, 118 __u8 *buf, size_t buf__sz) __weak __ksym; 119 extern int hid_bpf_input_report(struct hid_bpf_ctx *ctx, 120 enum hid_report_type type, 121 __u8 *data, 122 size_t buf__sz) __weak __ksym; 123 extern int hid_bpf_try_input_report(struct hid_bpf_ctx *ctx, 124 enum hid_report_type type, 125 __u8 *data, 126 size_t buf__sz) __weak __ksym; 127 128 /* bpf_wq implementation */ 129 extern int bpf_wq_init(struct bpf_wq *wq, void *p__map, unsigned int flags) __weak __ksym; 130 extern int bpf_wq_start(struct bpf_wq *wq, unsigned int flags) __weak __ksym; 131 extern int bpf_wq_set_callback(struct bpf_wq *wq, 132 int (*callback_fn)(void *, int *, void *), 133 unsigned int flags) __weak __ksym; 134 135 #endif /* __HID_BPF_HELPERS_H */ 136