/* SPDX-License-Identifier: GPL-2.0-only */ #ifndef _CBFS_H_ #define _CBFS_H_ #include #include #include #include #include #include #include #include /********************************************************************************************** * CBFS FILE ACCESS APIs * **********************************************************************************************/ /* * These are the APIs used to access files in CBFS. In order to keep the calls simple and free * of clutter in the common cases, but still offer all advanced functionality when needed, there * are many different variations that are implemented by wrapping the same underlying API with * static inlines. All accessors have in common that they look up files by name, and will * transparently decompress files that are compressed. * * There are three main flavors of CBFS accessors: * * size_t cbfs_load(char *name, void *buf, size_t size): Loads the contents of a CBFS file into * a buffer provided by the caller (by providing pointer and size to it). Will return the * amount of bytes loaded on success, or 0 on error. * * void *cbfs_map(char *name, size_t *size_out): Maps a file into the address space. If the file * is not compressed and the platform supports direct memory-mapping for the boot medium, * a pointer to the platform mapping is returned directly. In all other cases, memory will * be allocated from the cbfs_cache and file data will be loaded into there. Returns a * pointer to the mapping on success, or NULL on error. If an optional size_out parameter * is passed in, it will be filled out with the size of the mapped data. Caller should call * cbfs_unmap() after it is done using the mapping to free up the cbfs_cache if possible. * * void *cbfs_alloc(char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out): Loads * file data into memory provided by a custom allocator function that the caller passes in. * The caller may pass an argument that is passed through verbatim to the allocator. * Returns the pointer returned by the allocator (where the file data was loaded to) on * success, or NULL on error. If an optional size_out parameter is passed in, it will be * filled out with the size of the loaded data. * * void *cbfs_cbmem_alloc(char *name, uint32_t cbmem_id, size_t *size_out): Wrapper around * cbfs_alloc() that will provide an allocator function for allocating space for the file * data in CBMEM, with the provided CBMEM ID. * * All of these flavors have variations with any of the following optional parameters added: * * ..._ro_...: Will force looking up the CBFS file in the read-only CBFS (the "COREBOOT" FMAP * section), even when running in an RW stage from one of the RW CBFSs. Only relevant if * CONFIG(VBOOT) is set. * * ..._unverified_area_...: Will look for the CBFS file in the named FMAP area, rather than * any of the default (RO or RW) CBFSs. Files accessed this way are *not* verified in any * way (even if CONFIG(CBFS_VERIFICATION) is enabled) and should always be treated as * untrusted (potentially malicious) data. Mutually exclusive with the ..._ro_... variant. * * ..._type_...: May pass in an extra enum cbfs_type *type parameter. If the value it points to * is CBFS_TYPE_QUERY, it will be replaced with the actual CBFS type of the found file. If * it is anything else, the type will be compared with the actually found type, and the * operation will fail if they don't match. */ /* * An allocator function for passing to cbfs_alloc(). Takes the argument that was originally * passed to cbfs_alloc(), the size of the file to be loaded, and a pointer to the already * loaded and verified file metadata (for rare cases where the allocator needs to check custom * attributes). Must return a pointer to space of the requested size where the file data should * be loaded, or NULL to make the operation fail. */ typedef void *(*cbfs_allocator_t)(void *arg, size_t size, const union cbfs_mdata *mdata); static inline size_t cbfs_load(const char *name, void *buf, size_t size); static inline size_t cbfs_ro_load(const char *name, void *buf, size_t size); static inline size_t cbfs_type_load(const char *name, void *buf, size_t size, enum cbfs_type *type); static inline size_t cbfs_ro_type_load(const char *name, void *buf, size_t size, enum cbfs_type *type); static inline size_t cbfs_unverified_area_load(const char *area, const char *name, void *buf, size_t size); static inline void *cbfs_map(const char *name, size_t *size_out); static inline void *cbfs_ro_map(const char *name, size_t *size_out); static inline void *cbfs_type_map(const char *name, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_ro_type_map(const char *name, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_unverified_area_map(const char *area, const char *name, size_t *size_out); static inline void *cbfs_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out); static inline void *cbfs_ro_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out); static inline void *cbfs_type_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_ro_type_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_unverified_area_alloc(const char *area, const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out); static inline void *cbfs_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out); static inline void *cbfs_ro_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out); static inline void *cbfs_type_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_ro_type_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out, enum cbfs_type *type); static inline void *cbfs_unverified_area_cbmem_alloc(const char *area, const char *name, uint32_t cbmem_id, size_t *size_out); /* * Starts the processes of preloading a file into RAM. * * This method depends on COOP_MULTITASKING to parallelize the loading. This method is only * effective when the underlying rdev supports DMA operations. * * When `cbfs_load`, `cbfs_alloc`, or `cbfs_map` are called after a preload has been started, * they will wait for the preload to complete (if it hasn't already) and then perform * verification and/or decompression. * * This method does not have a return value because the system should boot regardless if this * method succeeds or fails. */ void cbfs_preload(const char *name); /* Removes a previously allocated CBFS mapping. Should try to unmap mappings in strict LIFO order where possible, since mapping backends often don't support more complicated cases. */ void cbfs_unmap(void *mapping); /* Load stage into memory filling in prog. Return 0 on success. < 0 on error. */ enum cb_err cbfs_prog_stage_load(struct prog *prog); /* Returns the size of a CBFS file, or 0 on error. Avoid using this function to allocate space, and instead use cbfs_alloc() so the file only needs to be looked up once. */ static inline size_t cbfs_get_size(const char *name); static inline size_t cbfs_ro_get_size(const char *name); /* Returns the type of a CBFS file, or CBFS_TYPE_NULL on error. Use cbfs_type_load() instead of this where possible to avoid looking up the file more than once. */ static inline enum cbfs_type cbfs_get_type(const char *name); static inline enum cbfs_type cbfs_ro_get_type(const char *name); /* Check whether a CBFS file exists. */ static inline bool cbfs_file_exists(const char *name); static inline bool cbfs_ro_file_exists(const char *name); /********************************************************************************************** * BOOT DEVICE HELPER APIs * **********************************************************************************************/ /* * The shared memory pool for backing mapped CBFS files, and other CBFS allocation needs. */ extern struct mem_pool cbfs_cache; /* * Data structure that represents "a" CBFS boot device, with optional metadata cache. Generally * we only have one of these, or two (RO and RW) when CONFIG(VBOOT) is set. The region device * stored here must always be a subregion of boot_device_ro(). */ struct cbfs_boot_device { struct region_device rdev; void *mcache; size_t mcache_size; }; /* Helper to fill out |mcache| and |mcache_size| in a cbfs_boot_device. */ void cbfs_boot_device_find_mcache(struct cbfs_boot_device *cbd, uint32_t id); /* * Retrieves the currently active CBFS boot device. If |force_ro| is set, will always return the * read-only CBFS instead (this only makes a difference when CONFIG(VBOOT) is enabled). May * perform certain CBFS initialization tasks. Returns NULL on error (e.g. boot device IO error). */ const struct cbfs_boot_device *cbfs_get_boot_device(bool force_ro); /* * Builds the mcache (if |cbd->mcache| is set) and verifies |metadata_hash| (if it is not NULL). * If CB_CBFS_CACHE_FULL is returned, the mcache is incomplete but still valid and the metadata * hash was still verified. Should be called once per *boot* (not once per stage) before the * first CBFS access. */ enum cb_err cbfs_init_boot_device(const struct cbfs_boot_device *cbd, struct vb2_hash *metadata_hash); /********************************************************************************************** * INTERNAL HELPERS FOR INLINES, DO NOT USE. * **********************************************************************************************/ enum cb_err _cbfs_boot_lookup(const char *name, bool force_ro, union cbfs_mdata *mdata, struct region_device *rdev); void *_cbfs_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out, bool force_ro, enum cbfs_type *type); void *_cbfs_unverified_area_alloc(const char *area, const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out); struct _cbfs_default_allocator_arg { void *buf; size_t buf_size; }; void *_cbfs_default_allocator(void *arg, size_t size, const union cbfs_mdata *unused); void *_cbfs_cbmem_allocator(void *arg, size_t size, const union cbfs_mdata *unused); /********************************************************************************************** * INLINE IMPLEMENTATIONS * **********************************************************************************************/ static inline void *cbfs_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out) { return cbfs_type_alloc(name, allocator, arg, size_out, NULL); } static inline void *cbfs_ro_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out) { return cbfs_ro_type_alloc(name, allocator, arg, size_out, NULL); } static inline void *cbfs_type_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out, enum cbfs_type *type) { return _cbfs_alloc(name, allocator, arg, size_out, false, type); } static inline void *cbfs_ro_type_alloc(const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out, enum cbfs_type *type) { return _cbfs_alloc(name, allocator, arg, size_out, true, type); } static inline void *cbfs_unverified_area_alloc(const char *area, const char *name, cbfs_allocator_t allocator, void *arg, size_t *size_out) { return _cbfs_unverified_area_alloc(area, name, allocator, arg, size_out); } static inline void *cbfs_map(const char *name, size_t *size_out) { return cbfs_type_map(name, size_out, NULL); } static inline void *cbfs_ro_map(const char *name, size_t *size_out) { return cbfs_ro_type_map(name, size_out, NULL); } static inline void *cbfs_type_map(const char *name, size_t *size_out, enum cbfs_type *type) { return cbfs_type_alloc(name, NULL, NULL, size_out, type); } static inline void *cbfs_ro_type_map(const char *name, size_t *size_out, enum cbfs_type *type) { return cbfs_ro_type_alloc(name, NULL, NULL, size_out, type); } static inline void *cbfs_unverified_area_map(const char *area, const char *name, size_t *size_out) { return _cbfs_unverified_area_alloc(area, name, NULL, NULL, size_out); } static inline size_t _cbfs_load(const char *name, void *buf, size_t size, bool force_ro, enum cbfs_type *type) { struct _cbfs_default_allocator_arg arg = { .buf = buf, .buf_size = size }; if (_cbfs_alloc(name, _cbfs_default_allocator, &arg, &size, force_ro, type)) return size; else return 0; } static inline size_t cbfs_load(const char *name, void *buf, size_t size) { return cbfs_type_load(name, buf, size, NULL); } static inline size_t cbfs_type_load(const char *name, void *buf, size_t size, enum cbfs_type *type) { return _cbfs_load(name, buf, size, false, type); } static inline size_t cbfs_ro_load(const char *name, void *buf, size_t size) { return cbfs_ro_type_load(name, buf, size, NULL); } static inline size_t cbfs_ro_type_load(const char *name, void *buf, size_t size, enum cbfs_type *type) { return _cbfs_load(name, buf, size, true, type); } static inline size_t cbfs_unverified_area_load(const char *area, const char *name, void *buf, size_t size) { struct _cbfs_default_allocator_arg arg = { .buf = buf, .buf_size = size }; if (_cbfs_unverified_area_alloc(area, name, _cbfs_default_allocator, &arg, &size)) return size; else return 0; } static inline void *cbfs_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out) { return cbfs_type_cbmem_alloc(name, cbmem_id, size_out, NULL); } static inline void *cbfs_ro_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out) { return cbfs_ro_type_cbmem_alloc(name, cbmem_id, size_out, NULL); } static inline void *cbfs_type_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out, enum cbfs_type *type) { return cbfs_type_alloc(name, _cbfs_cbmem_allocator, (void *)(uintptr_t)cbmem_id, size_out, type); } static inline void *cbfs_ro_type_cbmem_alloc(const char *name, uint32_t cbmem_id, size_t *size_out, enum cbfs_type *type) { return cbfs_ro_type_alloc(name, _cbfs_cbmem_allocator, (void *)(uintptr_t)cbmem_id, size_out, type); } static inline void *cbfs_unverified_area_cbmem_alloc(const char *area, const char *name, uint32_t cbmem_id, size_t *size_out) { return _cbfs_unverified_area_alloc(area, name, _cbfs_cbmem_allocator, (void *)(uintptr_t)cbmem_id, size_out); } static inline size_t cbfs_get_size(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, false, &mdata, &rdev) != CB_SUCCESS) return 0; return be32toh(mdata.h.len); } static inline size_t cbfs_ro_get_size(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, true, &mdata, &rdev) != CB_SUCCESS) return 0; return be32toh(mdata.h.len); } static inline enum cbfs_type cbfs_get_type(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, false, &mdata, &rdev) != CB_SUCCESS) return CBFS_TYPE_NULL; return be32toh(mdata.h.type); } static inline enum cbfs_type cbfs_ro_get_type(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, true, &mdata, &rdev) != CB_SUCCESS) return CBFS_TYPE_NULL; return be32toh(mdata.h.type); } static inline bool cbfs_file_exists(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, false, &mdata, &rdev) != CB_SUCCESS) return false; return true; } static inline bool cbfs_ro_file_exists(const char *name) { union cbfs_mdata mdata; struct region_device rdev; if (_cbfs_boot_lookup(name, true, &mdata, &rdev) != CB_SUCCESS) return false; return true; } #endif