100 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			100 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
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| /* Copyright (c) 2019 Facebook */
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| 
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| #ifndef __RELO_CORE_H
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| #define __RELO_CORE_H
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| 
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| #include <linux/bpf.h>
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| 
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| struct bpf_core_cand {
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| 	const struct btf *btf;
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| 	__u32 id;
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| };
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| 
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| /* dynamically sized list of type IDs and its associated struct btf */
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| struct bpf_core_cand_list {
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| 	struct bpf_core_cand *cands;
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| 	int len;
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| };
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| 
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| #define BPF_CORE_SPEC_MAX_LEN 64
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| 
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| /* represents BPF CO-RE field or array element accessor */
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| struct bpf_core_accessor {
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| 	__u32 type_id;		/* struct/union type or array element type */
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| 	__u32 idx;		/* field index or array index */
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| 	const char *name;	/* field name or NULL for array accessor */
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| };
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| 
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| struct bpf_core_spec {
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| 	const struct btf *btf;
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| 	/* high-level spec: named fields and array indices only */
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| 	struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN];
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| 	/* original unresolved (no skip_mods_or_typedefs) root type ID */
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| 	__u32 root_type_id;
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| 	/* CO-RE relocation kind */
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| 	enum bpf_core_relo_kind relo_kind;
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| 	/* high-level spec length */
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| 	int len;
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| 	/* raw, low-level spec: 1-to-1 with accessor spec string */
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| 	int raw_spec[BPF_CORE_SPEC_MAX_LEN];
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| 	/* raw spec length */
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| 	int raw_len;
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| 	/* field bit offset represented by spec */
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| 	__u32 bit_offset;
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| };
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| 
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| struct bpf_core_relo_res {
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| 	/* expected value in the instruction, unless validate == false */
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| 	__u64 orig_val;
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| 	/* new value that needs to be patched up to */
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| 	__u64 new_val;
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| 	/* relocation unsuccessful, poison instruction, but don't fail load */
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| 	bool poison;
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| 	/* some relocations can't be validated against orig_val */
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| 	bool validate;
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| 	/* for field byte offset relocations or the forms:
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| 	 *     *(T *)(rX + <off>) = rY
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| 	 *     rX = *(T *)(rY + <off>),
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| 	 * we remember original and resolved field size to adjust direct
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| 	 * memory loads of pointers and integers; this is necessary for 32-bit
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| 	 * host kernel architectures, but also allows to automatically
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| 	 * relocate fields that were resized from, e.g., u32 to u64, etc.
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| 	 */
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| 	bool fail_memsz_adjust;
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| 	__u32 orig_sz;
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| 	__u32 orig_type_id;
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| 	__u32 new_sz;
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| 	__u32 new_type_id;
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| };
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| 
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| int __bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
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| 				const struct btf *targ_btf, __u32 targ_id, int level);
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| int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id,
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| 			      const struct btf *targ_btf, __u32 targ_id);
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| int __bpf_core_types_match(const struct btf *local_btf, __u32 local_id, const struct btf *targ_btf,
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| 			   __u32 targ_id, bool behind_ptr, int level);
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| int bpf_core_types_match(const struct btf *local_btf, __u32 local_id, const struct btf *targ_btf,
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| 			 __u32 targ_id);
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| 
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| size_t bpf_core_essential_name_len(const char *name);
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| 
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| int bpf_core_calc_relo_insn(const char *prog_name,
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| 			    const struct bpf_core_relo *relo, int relo_idx,
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| 			    const struct btf *local_btf,
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| 			    struct bpf_core_cand_list *cands,
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| 			    struct bpf_core_spec *specs_scratch,
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| 			    struct bpf_core_relo_res *targ_res);
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| 
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| int bpf_core_patch_insn(const char *prog_name, struct bpf_insn *insn,
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| 			int insn_idx, const struct bpf_core_relo *relo,
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| 			int relo_idx, const struct bpf_core_relo_res *res);
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| 
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| int bpf_core_parse_spec(const char *prog_name, const struct btf *btf,
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| 		        const struct bpf_core_relo *relo,
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| 		        struct bpf_core_spec *spec);
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| 
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| int bpf_core_format_spec(char *buf, size_t buf_sz, const struct bpf_core_spec *spec);
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| 
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| #endif
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