oor: Use string matching for supported-but-modified bootloaders

Change-Id: I4daf18a31f2021dd542a0b34eadd4c865fa52643

diff --git a/oor/Android.bp b/oor/Android.bp
index ec798a9f6b2aad02822b29a0164957a098fe8d7f..1a379435aafe61709dc78578c21726413870b736 100644 (file)
--- a/oor/Android.bp
+++ b/oor/Android.bp
@@ -43,6 +43,7 @@ cc_binary {
         "src/cmd_list.c",
         "src/cmd_undo.c",
         "src/crc.c",
+        "src/bl_check.c",
         "src/main.c",
         ":patch_code",
     ],

diff --git a/oor/Makefile b/oor/Makefile
index ded950f372a15d6446393917e56b76a5a5e2ffe5..53bb8ae7dbe47fe6e7af750fc415c5acebb2db14 100644 (file)
--- a/oor/Makefile
+++ b/oor/Makefile
@@ -5,7 +5,7 @@ ARM_CC ?= arm-linux-androideabi-gcc
 ARM_OBJCOPY ?= $(ARM_CC:%gcc=%)objcopy
 
 OOR_MODULES := aboot_image asm boot_image cmd_crc cmd_list cmd_patch cmd_redirect \
-               cmd_undo cmd_verify config crc file_utils little_endian main
+               cmd_undo cmd_verify config crc file_utils little_endian bl_check main
 ASM_MODULES := patch_code
 BIN_TO_C_MODULES := bin_to_c file_utils
 

diff --git a/oor/src/bl_check.c b/oor/src/bl_check.c
new file mode 100644 (file)
index 0000000..ec8953e
--- /dev/null
+++ b/oor/src/bl_check.c
@@ -0,0 +1,125 @@
+#include "bl_check.h"
+#include "config.h"
+#include "crc.h"
+
+#include <stdio.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+char *find_bytes(char *mem, size_t mem_len, char *to_find, size_t to_find_len) {
+    char *ret = NULL;
+
+    for(size_t i = 0; i <= mem_len - to_find_len; i++) {
+        size_t j = 0;
+        while(j < to_find_len && mem[i + j] == to_find[j]) {
+            j++;
+        }
+        if(j == to_find_len) {
+            ret = &mem[i];
+            break;
+        }
+    }
+
+    return ret;
+}
+
+char *get_next_string(char *mem, size_t mem_len, char *curr_ptr) {
+    char *ret = NULL;
+
+    if(!curr_ptr) {
+        goto out;
+    }
+
+    size_t i = curr_ptr - mem;
+    size_t j;
+
+    /* Get to the end of the current string */
+    while(i < mem_len && mem[i] != 0) {
+        i++;
+    }
+
+    /* Get to the start of the next string */
+    while(i < mem_len && mem[i] == 0) {
+        i++;
+    }
+
+    /* Make sure the next string terminates */
+    j = i;
+    while(j < mem_len && mem[j] != 0) {
+        j++;
+    }
+
+    if(i != mem_len && j != mem_len) {
+        ret = mem + i;
+    }
+
+out:
+    return ret;
+}
+
+bootloader_config *get_config_from_crc(char *bl_code, size_t bl_code_len) {
+    bootloader_config *config = NULL;
+    uint32_t bl_crc = 0;
+
+    bl_crc = crc32(bl_code, bl_code_len);
+    for(size_t i = 0; i < num_configs; i++) {
+        if(configs[i].code_crc == bl_crc) {
+            config = &configs[i];
+            break;
+        }
+    }
+
+    return config;
+}
+
+char bl_equals_str[] = "androidboot.bootloader=%s";
+
+bootloader_config *get_config_from_string(char *bl_code, size_t bl_code_len) {
+    bootloader_config *config = NULL;
+    char *bl_str = NULL;
+
+    bl_str = find_bytes(bl_code, bl_code_len, bl_equals_str, sizeof(bl_equals_str));
+    bl_str = get_next_string(bl_code, bl_code_len, bl_str);
+
+    if(!bl_str) {
+        goto out;
+    }
+
+    for(size_t i = 0; i < num_configs; i++) {
+        if(!strcmp(configs[i].name, bl_str)) {
+            config = &configs[i];
+            break;
+        }
+    }
+
+out:
+    return config;
+}
+
+bootloader_config *get_config(char *bl_code, size_t bl_code_len) {
+    bootloader_config *ret = NULL;
+
+    if(bl_code_len < 0x40000) {
+        goto out;
+    }
+
+    ret = get_config_from_crc(bl_code, bl_code_len);
+
+    if(!ret) {
+        ret = get_config_from_string(bl_code, bl_code_len);
+        if(ret) {
+            printf("WARNING: CRC Mismatch\n");
+        }
+    }
+
+out:
+    if(ret) {
+        printf("Bootloader found: %s\n", ret->name);
+    } else {
+        printf("Unsupported bootloader\n");
+    }
+
+    return ret;
+}

diff --git a/oor/src/bl_check.h b/oor/src/bl_check.h
new file mode 100644 (file)
index 0000000..0a2d50f
--- /dev/null
+++ b/oor/src/bl_check.h
@@ -0,0 +1,10 @@
+#ifndef _BL_CHECK_H
+#define _BL_CHECK_H
+
+#include "config.h"
+
+#include <stdint.h>
+
+bootloader_config *get_config(char *bl_code, size_t bl_code_len);
+
+#endif

diff --git a/oor/src/cmd_patch.c b/oor/src/cmd_patch.c
index 033b49f95930b3036b302c08d0926d63f5862ec7..cea03a6c6d6e00d05062318c9de56b7afa77c8a1 100644 (file)
--- a/oor/src/cmd_patch.c
+++ b/oor/src/cmd_patch.c
@@ -5,6 +5,7 @@
 #include "crc.h"
 #include "asm.h"
 #include "little_endian.h"
+#include "bl_check.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -43,16 +44,8 @@ int cmd_patch_main(int argc, char *argv[]) {
     bl_code = bootloader->code_ptr;
     bl_code_len = bootloader->code_size;
 
-    bl_crc = crc32(bl_code, bl_code_len);
-    for(size_t i = 0; i < num_configs; i++) {
-        if(configs[i].code_crc == bl_crc) {
-            config = &configs[i];
-            printf("Supported bootloader found: %s\n", config->name);
-            break;
-        }
-    }
+    config = get_config(bl_code, bl_code_len);
     if(!config) {
-        printf("Unsupported bootloader\n");
         goto out;
     }
 
@@ -81,7 +74,9 @@ int cmd_patch_main(int argc, char *argv[]) {
         printf("Failed to embed original boot image\n");
         goto out;
     }
+
     image_kernel[3] = 1;
+    bl_crc = crc32(bl_code, bl_code_len);
     le_uint32_write(bl_crc, image_kernel, 4);
 
     image_ramdisk = make_exploit_ramdisk(bl_code, bl_code_len, config,

diff --git a/oor/src/cmd_redirect.c b/oor/src/cmd_redirect.c
index bc789de47d373902d270d7c0101b25e42b766b33..bff3713530b046d2a747e82b1f6f477e13758147 100644 (file)
--- a/oor/src/cmd_redirect.c
+++ b/oor/src/cmd_redirect.c
@@ -5,6 +5,7 @@
 #include "crc.h"
 #include "asm.h"
 #include "little_endian.h"
+#include "bl_check.h"
 
 #include <stdio.h>
 #include <string.h>
@@ -69,16 +70,8 @@ int cmd_redirect_main(int argc, char *argv[]) {
     bl_code = bootloader->code_ptr;
     bl_code_len = bootloader->code_size;
 
-    bl_crc = crc32(bl_code, bl_code_len);
-    for(size_t i = 0; i < num_configs; i++) {
-        if(configs[i].code_crc == bl_crc) {
-            config = &configs[i];
-            printf("Supported bootloader found: %s\n", config->name);
-            break;
-        }
-    }
+    config = get_config(bl_code, bl_code_len);
     if(!config) {
-        printf("Unsupported bootloader\n");
         goto out;
     }
 
@@ -88,6 +81,7 @@ int cmd_redirect_main(int argc, char *argv[]) {
         goto out;
     }
 
+    bl_crc = crc32(bl_code, bl_code_len);
     image_kernel = make_redirect_binary(argv[3], bl_crc, &image_kernel_len);
     if(!image_kernel) {
         printf("Failed to generate redirect binary\n");