initial commit

.gitignore

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+# General
+.DS_Store
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Useless project files
+.zed
+*.dSYM

Makefile

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+SYS_ARCH := $(shell uname -m)
+
+CC = clang
+CFLAGS = -Iinclude -O3 -Wall
+
+SRC = src/memory.c src/tinyhook.c
+OBJ = $(SRC:.c=.o)
+LIB = lib/libtinyhook.a
+TST = tests/example
+
+ifeq ($(SYS_ARCH), x86_64)
+	OBJ += src/fde64/fde64.o
+endif
+
+build: $(LIB)
+
+test: $(TST)
+
+all: $(LIB) $(TST)
+
+$(LIB): $(OBJ)
+	ar rcs $@ $^
+
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+tests/example: tests/example.c $(LIB)
+	$(CC) $(CFLAGS) -ltinyhook -Llib $< -o $@
+
+.PHONY: clean
+clean:
+	rm -f $(LIB) $(TST) src/memory.o src/tinyhook.o

README.md

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+# tinyhook
+
+A tiny macOS inline hook framework
+
+**Now support both ARM64 and x86_64!**
+
+## functions
+
+### read and write memory
+
+```c
+int read_mem(void *destnation, const void *source, size_t len);
+int write_mem(void *destnation, const void *source, size_t len);
+```
+
+### insert a jump at an address
+
+`tiny_insert()` uses `bl` or `b` (depends on `link` flag) on ARM64, and `jmp` or `call` on x86_64
+
+`tiny_isnert_far()`  uses `adrp` + `blr`/`br` on ARM64, and `jmp` or call on x86_64
+
+```c
+int tiny_insert(void *address, void *destnation, bool link);
+int tiny_insert_far(void *address, void *destnation, bool link);
+```
+
+### inline hook
+
+`origin` can be `NULL`
+
+```c
+int tiny_hook(void *function, void *destnation, void **origin);
+```
+
+## examples
+
+```c
+#include <stdio.h>
+#include <mach-o/dyld.h>
+
+#include "tinyhook.h"
+
+uint32_t (*orig_dyld_image_count)(void);
+uint32_t my_dyld_image_count(void) {
+	uint32_t image_count = orig_dyld_image_count();
+	printf("hooked _dyld_image_count: %d!\n", image_count);
+	return 5;
+}
+
+int main() {
+	int image_count = _dyld_image_count();
+	for (int i = 0; i < image_count; i++) {
+		printf("image[%d]: %s\n", i, _dyld_get_image_name(i));
+	}
+
+	tiny_hook(_dyld_image_count, my_dyld_image_count, (void **)&orig_dyld_image_count);
+
+	int image_count = _dyld_image_count();
+	for (int i = 0; i < image_count; i++) {
+		printf("image[%d]: %s\n", i, _dyld_get_image_name(i));
+	}
+	return 0;
+}
+```
+
+## references
+
+Thanks to these projects for their inspiring idea and code!
+
+- https://github.com/rodionovd/rd_route
+- https://github.com/GiveMeZeny/fde64

include/tinyhook.h

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+#ifndef tinyhook_h
+#define tinyhook_h
+
+#include <stddef.h>
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int read_mem(void *destnation, const void *source, size_t len);
+
+int write_mem(void *destnation, const void *source, size_t len);
+
+int tiny_hook(void *function, void *destnation, void **origin);
+
+int tiny_insert(void *address, void *destnation, bool link);
+
+int tiny_insert_far(void *address, void *destnation, bool link);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif