authbl1 with bl1 works

reven/SamsungS7.lock

@@ -1,9 +1,9 @@
 #Ghidra Lock File
-#Tue Aug 06 19:30:30 CEST 2024
+#Fri Aug 09 11:27:43 CEST 2024
 OS\ Name=Linux
 OS\ Version=6.5.0-44-generic
 Username=eljakim
 Hostname=levith
 <META>\ Supports\ File\ Channel\ Locking=Channel Lock
 OS\ Architecture=amd64
-Timestamp=8/6/24, 7\:30 PM
+Timestamp=8/9/24, 11\:27 AM

source/exploit/exploit.py

@@ -222,25 +222,51 @@ class ExynosDevice():
         Room for playing around with the debugger
         '''
         self.cd.arch_dbg.state.auto_sync = False
+        self.cd.arch_dbg.state.auto_sync_special = False
         self.cd.arch_dbg.state.print_ctx()
         
+        def relocate_debugger():
+            # Seems to be cleared upon cache clearing??
+            debugger_reloc = open("/home/eljakim/Source/gupje/source/bin/samsung_s7/reloc_debugger.bin", "rb").read()
+            self.cd.memwrite_region(0x020c0000, debugger_reloc)
+            self.usb_write(b"FLSH") # Flush cache
+            self.cd.restore_stack_and_jump(0x020c0000)
+            assert self.usb_read(0x200) == b"GiAs", "Failed to relocate debugger"
+            self.cd.relocate_debugger(0x020c7000, 0x020c0000, 0x020c4000)
+        relocate_debugger()
+        
+        # Try loading bl1
+        bl1 = open("../S7/bl1.bin", "rb").read()
+        self.cd.memwrite_region(0x02021800, bl1)
+        # self.usb_write(b"FLSH")
+        AUTH_BL1 = 0x00012848
+        def auth_bl1(lr=0x2069000):
+            # Load the firmware
+            self.cd.arch_dbg.state.W0 = 1
+            self.cd.arch_dbg.state.X1 = 1
+            self.cd.arch_dbg.state.LR = lr #jump back to debugger when finished
+            self.cd.restore_stack_and_jump(AUTH_BL1)
+            assert self.usb_read(0x200) == b"GiAs", "Failed to jump back to debugger"
+            
+        auth_bl1(0x020c0000)
+        
+        # Works until here
+        
+        pass
+        
+        
+        
         # Overwrite jump back
         self.cd.memwrite_region(0x02020108, p32(0x2069000))
-        # self.cd.memwrite_region(0x020200e8, p32(0x2069000))
+        self.cd.memwrite_region(0x020200e8, p32(0x2069000))
         
-        AUTH_BL1 = 0x00012848
         def memdump_try():
             dumped = b""
             for block in range(0x2020000, 0x2200000, 0x200):
                 print(hex(block))
                 dumped += self.cd.memdump_region(block, 0x200)
                 
-        def auth_bl1():
+        
-            # Load the firmware
-            self.cd.arch_dbg.state.X0 = 1
-            self.cd.arch_dbg.state.X1 = 1
-            self.cd.arch_dbg.state.LR = 0x2069000 #jump back to debugger when finished
-            self.cd.restore_stack_and_jump(AUTH_BL1)
             
         def jump_bl1():
             self.cd.arch_dbg.state.LR = 0x2069000
@@ -252,9 +278,9 @@ class ExynosDevice():
         # self.cd.restore_stack_and_jump(0x00012814)
         # self.cd.restore_stack_and_jump(0x000125b4)
         
-        bl1 = open("../S7/bl1.bin", "rb").read()
+        
-        self.cd.memwrite_region(0x02024000, bl1)
+        
-        self.usb_write(b"FLSH")
+        auth_bl1()
         
         # auth_bl1()
         jump_bl1()

source/gupje_device/Makefile

@@ -8,10 +8,21 @@ OBJCOPY := $(ANDROID_NDK_ROOT)/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64
 LD := $(ANDROID_NDK_ROOT)/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android-ld.bfd
 
 #==================Target Samsung S7 (8890)==================
+all: samsung_s7 samsung_s7_reloc
+
 CFLAGS_SAMSUNGS7 = -Os -Idevices/samsung_s7/
 samsung_s7:
 	[ -d bin/samsung_s7 ] || mkdir -p bin/samsung_s7/
 	$(CC) arm64_stub.S -c -o bin/samsung_s7/entry.o $(CFLAGS_SAMSUNGS7)
 	$(CC) debugger.c -c -o bin/samsung_s7/debugger.o $(CFLAGS_SAMSUNGS7)
 	$(LD) -T devices/samsung_s7/linkscript.ld bin/samsung_s7/entry.o bin/samsung_s7/debugger.o -o bin/samsung_s7/debugger.elf --just-symbols=devices/samsung_s7/symbols.txt
-	$(OBJCOPY) -O binary bin/samsung_s7/debugger.elf bin/samsung_s7/debugger.bin
+	$(OBJCOPY) -O binary bin/samsung_s7/debugger.elf bin/samsung_s7/debugger.bin
+
+CFLAGS_SAMSUNGS7_RELOC = -Os -DRELOC_DEBUGGER=1 -Idevices/samsung_s7/ 
+samsung_s7_reloc:
+	[ -d bin/samsung_s7 ] || mkdir -p bin/samsung_s7/
+	$(CC) arm64_stub.S -c -o bin/samsung_s7/reloc_entry.o $(CFLAGS_SAMSUNGS7_RELOC)
+	$(CC) debugger.c -c -o bin/samsung_s7/reloc_debugger.o $(CFLAGS_SAMSUNGS7_RELOC)
+	$(LD) -T devices/samsung_s7/reloc_linkscript.ld bin/samsung_s7/reloc_entry.o bin/samsung_s7/reloc_debugger.o -o bin/samsung_s7/reloc_debugger.elf --just-symbols=devices/samsung_s7/reloc_symbols.txt
+	$(OBJCOPY) -O binary bin/samsung_s7/reloc_debugger.elf bin/samsung_s7/reloc_debugger.bin
+

source/gupje_device/Readme.md

@@ -1,8 +1,14 @@
 # Gupje
 Current memory map:
 
+## Stage 2
+Memory map in stage2 after exploitation
 ![memory map](memory_map.drawio.svg)
 
+## Stage 3
+Memory map in stage3 after relocating the debugger
+
+
 ## Usage:
 Copy this folder to <gupje>/devices/samsung_s7 and run:
 

source/gupje_device/device.h

@@ -8,6 +8,8 @@ extern int usb_event_handler(void);
 extern uint32_t get_endpoint_recv_buffer(char endpoint);
 extern void exynos_sleep(int endpoint,uint32_t timeout);
 extern void usb_send(uint32_t address,uint32_t size);
+extern uint32_t recv_buffer;
+extern uint32_t data_received;
 
 int mystrlen(char *data) {
     int i=0;
@@ -19,9 +21,13 @@ int mystrlen(char *data) {
     return i-1;
 }
 
-
+#ifdef RELOC_DEBUGGER
+#define recv_buffer 0x020c6200 
+#define data_received 0x020c6000
+#else
 #define recv_buffer 0x206fe00 //0x02021800 + 0x3000
 #define data_received 0x206fd00
+#endif
 
 void recv_data_cb(uint32_t endpoint, uint32_t len){
     char *dest_buf = (char *)recv_buffer;

source/gupje_device/reloc_linkscript.ld

@@ -0,0 +1,14 @@
+MEMORY {
+    ROM (rwx): ORIGIN = 0x020c0000, LENGTH = 0x1000
+}
+
+SECTIONS
+{
+     . = 0x020c0000;
+     .text . : {
+          *(.text*)
+          *(.data*)
+          *(.rodata*)
+     } >ROM
+
+}

source/gupje_device/reloc_symbols.txt

@@ -0,0 +1,12 @@
+debugger_storage = 0x020c4000;
+debugger_stack = 0x020c2000;
+debugger_entry = 0x020c0000;
+
+maybe_usb_setup_read = 0x00006f88;
+dwc3_ep0_start_trans = 0x0000791c;
+usb_event_handler = 0x00007bac;
+get_endpoint_recv_buffer = 0x00007a7c;
+exynos_sleep = 0x000027c8;
+
+g_recv_buffer = 0x020c6200;
+g_data_received = 0x020c6000;

source/gupje_device/symbols.txt

@@ -6,4 +6,6 @@ maybe_usb_setup_read = 0x00006f88;
 dwc3_ep0_start_trans = 0x0000791c;
 usb_event_handler = 0x00007bac;
 get_endpoint_recv_buffer = 0x00007a7c;
-exynos_sleep = 0x000027c8;
+exynos_sleep = 0x000027c8;
+
+RELOCATED = 0;