| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
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| 2 | /* |
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| 3 | * code tagging framework |
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| 4 | */ |
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| 5 | #ifndef _LINUX_CODETAG_H |
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| 6 | #define _LINUX_CODETAG_H |
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| 7 | |
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| 8 | #include <linux/types.h> |
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| 9 | |
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| 10 | struct codetag_iterator; |
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| 11 | struct codetag_type; |
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| 12 | struct codetag_module; |
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| 13 | struct seq_buf; |
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| 14 | struct module; |
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| 15 | |
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| 16 | #define CODETAG_SECTION_START_PREFIX "__start_" |
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| 17 | #define CODETAG_SECTION_STOP_PREFIX "__stop_" |
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| 18 | |
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| 19 | /* |
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| 20 | * An instance of this structure is created in a special ELF section at every |
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| 21 | * code location being tagged. At runtime, the special section is treated as |
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| 22 | * an array of these. |
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| 23 | */ |
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| 24 | struct codetag { |
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| 25 | unsigned int flags; /* used in later patches */ |
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| 26 | unsigned int lineno; |
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| 27 | const char *modname; |
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| 28 | const char *function; |
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| 29 | const char *filename; |
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| 30 | } __aligned(8); |
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| 31 | |
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| 32 | union codetag_ref { |
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| 33 | struct codetag *ct; |
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| 34 | }; |
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| 35 | |
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| 36 | struct codetag_type_desc { |
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| 37 | const char *section; |
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| 38 | size_t tag_size; |
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| 39 | int (*module_load)(struct module *mod, |
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| 40 | struct codetag *start, struct codetag *end); |
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| 41 | void (*module_unload)(struct module *mod, |
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| 42 | struct codetag *start, struct codetag *end); |
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| 43 | #ifdef CONFIG_MODULES |
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| 44 | void (*module_replaced)(struct module *mod, struct module *new_mod); |
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| 45 | bool (*needs_section_mem)(struct module *mod, unsigned long size); |
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| 46 | void *(*alloc_section_mem)(struct module *mod, unsigned long size, |
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| 47 | unsigned int prepend, unsigned long align); |
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| 48 | void (*free_section_mem)(struct module *mod, bool used); |
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| 49 | #endif |
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| 50 | }; |
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| 51 | |
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| 52 | struct codetag_iterator { |
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| 53 | struct codetag_type *cttype; |
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| 54 | struct codetag_module *cmod; |
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| 55 | unsigned long mod_id; |
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| 56 | struct codetag *ct; |
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| 57 | }; |
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| 58 | |
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| 59 | #ifdef MODULE |
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| 60 | #define CT_MODULE_NAME KBUILD_MODNAME |
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| 61 | #else |
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| 62 | #define CT_MODULE_NAME NULL |
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| 63 | #endif |
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| 64 | |
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| 65 | #define CODE_TAG_INIT { \ |
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| 66 | .modname = CT_MODULE_NAME, \ |
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| 67 | .function = __func__, \ |
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| 68 | .filename = __FILE__, \ |
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| 69 | .lineno = __LINE__, \ |
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| 70 | .flags = 0, \ |
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| 71 | } |
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| 72 | |
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| 73 | void codetag_lock_module_list(struct codetag_type *cttype, bool lock); |
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| 74 | bool codetag_trylock_module_list(struct codetag_type *cttype); |
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| 75 | struct codetag_iterator codetag_get_ct_iter(struct codetag_type *cttype); |
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| 76 | struct codetag *codetag_next_ct(struct codetag_iterator *iter); |
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| 77 | |
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| 78 | void codetag_to_text(struct seq_buf *out, struct codetag *ct); |
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| 79 | |
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| 80 | struct codetag_type * |
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| 81 | codetag_register_type(const struct codetag_type_desc *desc); |
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| 82 | |
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| 83 | #if defined(CONFIG_CODE_TAGGING) && defined(CONFIG_MODULES) |
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| 84 | |
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| 85 | bool codetag_needs_module_section(struct module *mod, const char *name, |
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| 86 | unsigned long size); |
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| 87 | void *codetag_alloc_module_section(struct module *mod, const char *name, |
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| 88 | unsigned long size, unsigned int prepend, |
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| 89 | unsigned long align); |
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| 90 | void codetag_free_module_sections(struct module *mod); |
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| 91 | void codetag_module_replaced(struct module *mod, struct module *new_mod); |
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| 92 | int codetag_load_module(struct module *mod); |
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| 93 | void codetag_unload_module(struct module *mod); |
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| 94 | |
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| 95 | #else /* defined(CONFIG_CODE_TAGGING) && defined(CONFIG_MODULES) */ |
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| 96 | |
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| 97 | static inline bool |
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| 98 | codetag_needs_module_section(struct module *mod, const char *name, |
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| 99 | unsigned long size) { return false; } |
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| 100 | static inline void * |
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| 101 | codetag_alloc_module_section(struct module *mod, const char *name, |
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| 102 | unsigned long size, unsigned int prepend, |
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| 103 | unsigned long align) { return NULL; } |
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| 104 | static inline void codetag_free_module_sections(struct module *mod) {} |
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| 105 | static inline void codetag_module_replaced(struct module *mod, struct module *new_mod) {} |
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| 106 | static inline int codetag_load_module(struct module *mod) { return 0; } |
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| 107 | static inline void codetag_unload_module(struct module *mod) {} |
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| 108 | |
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| 109 | #endif /* defined(CONFIG_CODE_TAGGING) && defined(CONFIG_MODULES) */ |
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| 110 | |
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| 111 | #endif /* _LINUX_CODETAG_H */ |
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| 112 | |
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