From b2015a0d8ae68d39126a431c61bd70d84e941efd Mon Sep 17 00:00:00 2001
From: mykola2312 <49044616+mykola2312@users.noreply.github.com>
Date: Sat, 24 Aug 2024 14:32:50 +0300
Subject: [PATCH] begin working on relf component

---
 Makefile                   |  2 +-
 README.md                  |  4 ++++
 src/relf/Makefile          | 26 ++++++++++++++++++++++++++
 src/relf/relf.c            |  1 +
 src/relf/relf.h            |  4 ++++
 src/relf_test/Makefile     | 31 +++++++++++++++++++++++++++++++
 src/relf_test/relf_dummy.c |  9 +++++++++
 src/relf_test/relf_test.c  |  8 ++++++++
 src/rtdisasm/Makefile      |  2 +-
 9 files changed, 85 insertions(+), 2 deletions(-)
 create mode 100644 src/relf/Makefile
 create mode 100644 src/relf/relf.c
 create mode 100644 src/relf/relf.h
 create mode 100644 src/relf_test/Makefile
 create mode 100644 src/relf_test/relf_dummy.c
 create mode 100644 src/relf_test/relf_test.c

diff --git a/Makefile b/Makefile
index b050888..2168203 100644
--- a/Makefile
+++ b/Makefile
@@ -28,7 +28,7 @@ export MAKE
 export PYTHON
 
 # order matters here, build libraries first!
-TARGETS				=	rtdisasm rtdisasm_test dummy_target blackjack
+TARGETS				=	rtdisasm rtdisasm_test relf relf_test dummy_target blackjack
 
 .PHONY: $(TARGETS) debug clean
 
diff --git a/README.md b/README.md
index c1463bb..05cb0bf 100644
--- a/README.md
+++ b/README.md
@@ -15,3 +15,7 @@ Hijacks runtime process in order to inject shared objects.
 ### rtdisasm
 
 KISS robust runtime "disassembler". Used to analyze instructions encoded sizes and find desired instructions for trampolines. No need to bloat it with full-blown disassembler logic like other projects do - one big lookup table is enough for such purposes.
+
+### relf
+
+Instrument to parse and analyze ELF shared objects. Primary goal is to find symbols and their offsets, so blackjack could link them in runtime.
diff --git a/src/relf/Makefile b/src/relf/Makefile
new file mode 100644
index 0000000..a0ecdf2
--- /dev/null
+++ b/src/relf/Makefile
@@ -0,0 +1,26 @@
+NAME				=	relf
+
+CFLAGS				=	-Wall -I$(INC_DIR)
+ASFLAGS				=
+LDFLAGS				=	-z noexecstack
+
+SRC		=	relf.c
+OBJ		:=	$(addprefix $(OBJ_DIR)/,$(patsubst %.s,%.o,$(patsubst %.c,%.o,$(SRC))))
+DEPS	=	relf.h
+
+$(OBJ_DIR)/%.o: %.c
+	@mkdir -p $(OBJ_DIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+.PHONY: all clean debug
+
+all: $(OBJ) $(DEPS)
+	$(AR) -crs $(BIN_DIR)/lib$(NAME).a $(OBJ)
+
+debug: CFLAGS += -DDEBUG -g
+debug: LDFLAGS += -g
+debug: ASFLAGS += -g
+debug: all
+
+clean:
+	rm -f $(OBJ_DIR)/*
\ No newline at end of file
diff --git a/src/relf/relf.c b/src/relf/relf.c
new file mode 100644
index 0000000..ff3427f
--- /dev/null
+++ b/src/relf/relf.c
@@ -0,0 +1 @@
+#include "relf/relf.h"
diff --git a/src/relf/relf.h b/src/relf/relf.h
new file mode 100644
index 0000000..c5643ba
--- /dev/null
+++ b/src/relf/relf.h
@@ -0,0 +1,4 @@
+#ifndef __RELF_H
+#define __RELF_H
+
+#endif
\ No newline at end of file
diff --git a/src/relf_test/Makefile b/src/relf_test/Makefile
new file mode 100644
index 0000000..439cd52
--- /dev/null
+++ b/src/relf_test/Makefile
@@ -0,0 +1,31 @@
+NAME				=	relf_test
+
+CFLAGS				=	-Wall -I$(INC_DIR)
+ASFLAGS				=
+LDFLAGS				=	-z noexecstack
+
+SRC		=	relf_test.c relf_dummy.c
+OBJ		:=	$(addprefix $(OBJ_DIR)/,$(patsubst %.s,%.o,$(patsubst %.c,%.o,$(SRC))))
+DEPS	=
+
+$(OBJ_DIR)/%.o: %.c
+	@mkdir -p $(OBJ_DIR)
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+$(OBJ_DIR)/%.o: %.s
+	@mkdir -p $(OBJ_DIR)
+	$(AS) $(ASFLAGS) -o $@ $<
+
+.PHONY: all clean debug
+
+all: $(OBJ) $(DEPS)
+	$(CC) $(LDFLAGS) -shared -o $(BIN_DIR)/relf_dummy.so obj/relf_dummy.o
+	$(CC) $(LDFLAGS) -o $(BIN_DIR)/relf_test obj/relf_test.o $(LIB_DIR)/librelf.a
+
+debug: CFLAGS += -DDEBUG -g
+debug: LDFLAGS += -g
+debug: ASFLAGS += -g
+debug: all
+
+clean:
+	rm -f $(OBJ_DIR)/*
\ No newline at end of file
diff --git a/src/relf_test/relf_dummy.c b/src/relf_test/relf_dummy.c
new file mode 100644
index 0000000..9af724f
--- /dev/null
+++ b/src/relf_test/relf_dummy.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+volatile int dummy_symbol1;
+volatile int dummy_symbol2;
+
+void dummy_function1()
+{
+    printf("hello from dummy_function1\n");
+}
diff --git a/src/relf_test/relf_test.c b/src/relf_test/relf_test.c
new file mode 100644
index 0000000..16af8bb
--- /dev/null
+++ b/src/relf_test/relf_test.c
@@ -0,0 +1,8 @@
+#include "relf/relf.h"
+#include <stdio.h>
+
+int main()
+{
+    printf("relf_test\n");
+    return 0;
+}
diff --git a/src/rtdisasm/Makefile b/src/rtdisasm/Makefile
index 510c5b8..95c6f48 100644
--- a/src/rtdisasm/Makefile
+++ b/src/rtdisasm/Makefile
@@ -2,7 +2,7 @@ NAME				=	rtdisasm
 
 CFLAGS				=	-Wall -I$(INC_DIR)
 ASFLAGS				=
-LDFLAGS				=	-z noexecstack -lcap
+LDFLAGS				=	-z noexecstack
 
 SRC		=	rtdisasm.c
 OBJ		:=	$(addprefix $(OBJ_DIR)/,$(patsubst %.s,%.o,$(patsubst %.c,%.o,$(SRC))))