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