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/*
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 * Copyright © 2018, M4xw
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 * Copyright © 2014, Owen Shepherd
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 *
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 * Permission to use, copy, modify, and/or distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
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 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
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 * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
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 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
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 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
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 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
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 * PERFORMANCE OF THIS SOFTWARE.
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 */
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#ifndef ELFLOAD_H
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#define ELFLOAD_H
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#include <stddef.h>
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#include "elfarch.h"
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#include "elf.h"
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#ifdef DEBUG
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#include <gfx_utils.h>
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#define EL_DEBUG(format, ...) \
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	gfx_printf(format __VA_OPT__(, ) __VA_ARGS__)
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#else
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#define EL_DEBUG(...) \
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	do                \
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	{                 \
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	} while (0)
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#endif
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typedef enum
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{
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	EL_OK = 0,
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	EL_EIO,
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	EL_ENOMEM,
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	EL_NOTELF,
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	EL_WRONGBITS,
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	EL_WRONGENDIAN,
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	EL_WRONGARCH,
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	EL_WRONGOS,
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	EL_NOTEXEC,
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	EL_NODYN,
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	EL_BADREL,
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} el_status;
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typedef struct el_ctx
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{
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	bool (*pread)(struct el_ctx *ctx, void *dest, size_t nb, size_t offset);
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	/* base_load_* -> address we are actually going to load at
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	 */
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	Elf_Addr
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		base_load_paddr,
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		base_load_vaddr;
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	/* size in memory of binary */
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	Elf_Addr memsz;
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	/* required alignment */
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	Elf_Addr align;
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	/* ELF header */
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	Elf_Ehdr ehdr;
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	// Section Header Str Table
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	Elf_Shdr shstr;
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	Elf_Shdr symtab;
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	/* Offset of dynamic table (0 if not ET_DYN) */
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	Elf_Off dynoff;
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	/* Size of dynamic table (0 if not ET_DYN) */
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	Elf_Addr dynsize;
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} el_ctx;
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el_status el_pread(el_ctx *ctx, void *def, size_t nb, size_t offset);
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el_status el_init(el_ctx *ctx);
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typedef void *(*el_alloc_cb)(
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	el_ctx *ctx,
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	Elf_Addr phys,
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	Elf_Addr virt,
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	Elf_Addr size);
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el_status el_load(el_ctx *ctx, el_alloc_cb alloccb);
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/* find the next phdr of type \p type, starting at \p *i.
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 * On success, returns EL_OK with *i set to the phdr number, and the phdr loaded
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 * in *phdr.
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 *
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 * If the end of the phdrs table was reached, *i is set to -1 and the contents
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 * of *phdr are undefined
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 */
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el_status el_findphdr(el_ctx *ctx, Elf_Phdr *phdr, u32 type, unsigned *i);
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/* Relocate the loaded executable */
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el_status el_relocate(el_ctx *ctx);
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/* find a dynamic table entry
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 * returns the entry on success, dyn->d_tag = DT_NULL on failure
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 */
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el_status el_finddyn(el_ctx *ctx, Elf_Dyn *dyn, u32 type);
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typedef struct
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{
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	Elf_Off tableoff;
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	Elf_Addr tablesize;
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	Elf_Addr entrysize;
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} el_relocinfo;
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/* find all information regarding relocations of a specific type.
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 *
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 * pass DT_REL or DT_RELA for type
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 * sets ri->entrysize = 0 if not found
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 */
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el_status el_findrelocs(el_ctx *ctx, el_relocinfo *ri, u32 type);
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#endif
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