commit d4bda8e59ffc61c65dcf4b42099d9bc71b7df46b
parent fd09537321a3855c703c57ece4f8636b2056a371
Author: Léo Villeveygoux <leo.villeveygoux@etu.u-bordeaux.fr>
Date: Fri, 16 Jun 2017 15:04:14 +0200
just a binary code loader at the moment
Diffstat:
| A | Makefile | | | 14 | ++++++++++++++ |
| A | b8.c | | | 29 | +++++++++++++++++++++++++++++ |
| A | test.asm | | | 24 | ++++++++++++++++++++++++ |
3 files changed, 67 insertions(+), 0 deletions(-)
diff --git a/Makefile b/Makefile
@@ -0,0 +1,14 @@
+LDFLAGS=-Wl,--section-start=mem_chunk=0x20000
+
+CARTS=$(patsubst %.asm,%.bin,$(wildcard *.asm))
+
+all: b8 $(CARTS)
+
+clean:
+ -$(RM) b8 *.bin
+
+%.bin: %.asm
+ yasm -f bin $< -o $@
+
+%.bin: %.s
+ yasm -f bin -r gas -p gas $< -o $@
diff --git a/b8.c b/b8.c
@@ -0,0 +1,29 @@
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+char buf[0x40000] __attribute__ ((section ("mem_chunk"))) = {0};
+
+int main(int argc, char *argv[]){
+ int (*f)(void) = NULL;
+
+ if(argc < 2)
+ return 1;
+
+ int fd = open(argv[1], O_RDONLY);
+ if(fd == -1) perror("open");
+
+ int ret = mprotect(&buf, 4096, PROT_READ|PROT_WRITE|PROT_EXEC);
+ if(ret) perror("mprotect");
+
+ int rdsize = read(fd, buf, 27);
+ if(rdsize != 27) perror("read");
+
+ f = (void*)buf;
+
+ printf("%d\n",*(int*)f());
+ return 0;
+}
diff --git a/test.asm b/test.asm
@@ -0,0 +1,24 @@
+org 0x20000
+bits 32
+
+call f
+ret
+nop
+nop
+nop
+nop
+nop
+
+f:
+mov eax, lol
+ret
+nop
+nop
+
+lol dd 42
+nop
+nop
+nop
+nop
+nop
+
