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-rw-r--r--minelf/Retouch.c196
1 files changed, 0 insertions, 196 deletions
diff --git a/minelf/Retouch.c b/minelf/Retouch.c
deleted file mode 100644
index d75eec1e8..000000000
--- a/minelf/Retouch.c
+++ /dev/null
@@ -1,196 +0,0 @@
-/*
- * Copyright (C) 2009 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <errno.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <string.h>
-#include <strings.h>
-#include "Retouch.h"
-#include "applypatch/applypatch.h"
-
-typedef struct {
- int32_t mmap_addr;
- char tag[4]; /* 'P', 'R', 'E', ' ' */
-} prelink_info_t __attribute__((packed));
-
-#define false 0
-#define true 1
-
-static int32_t offs_prev;
-static uint32_t cont_prev;
-
-static void init_compression_state(void) {
- offs_prev = 0;
- cont_prev = 0;
-}
-
-// For details on the encoding used for relocation lists, please
-// refer to build/tools/retouch/retouch-prepare.c. The intent is to
-// save space by removing most of the inherent redundancy.
-
-static void decode_bytes(uint8_t *encoded_bytes, int encoded_size,
- int32_t *dst_offset, uint32_t *dst_contents) {
- if (encoded_size == 2) {
- *dst_offset = offs_prev + (((encoded_bytes[0]&0x60)>>5)+1)*4;
-
- // if the original was negative, we need to 1-pad before applying delta
- int32_t tmp = (((encoded_bytes[0] & 0x0000001f) << 8) |
- encoded_bytes[1]);
- if (tmp & 0x1000) tmp = 0xffffe000 | tmp;
- *dst_contents = cont_prev + tmp;
- } else if (encoded_size == 3) {
- *dst_offset = offs_prev + (((encoded_bytes[0]&0x30)>>4)+1)*4;
-
- // if the original was negative, we need to 1-pad before applying delta
- int32_t tmp = (((encoded_bytes[0] & 0x0000000f) << 16) |
- (encoded_bytes[1] << 8) |
- encoded_bytes[2]);
- if (tmp & 0x80000) tmp = 0xfff00000 | tmp;
- *dst_contents = cont_prev + tmp;
- } else {
- *dst_offset =
- (encoded_bytes[0]<<24) |
- (encoded_bytes[1]<<16) |
- (encoded_bytes[2]<<8) |
- encoded_bytes[3];
- if (*dst_offset == 0x3fffffff) *dst_offset = -1;
- *dst_contents =
- (encoded_bytes[4]<<24) |
- (encoded_bytes[5]<<16) |
- (encoded_bytes[6]<<8) |
- encoded_bytes[7];
- }
-}
-
-static uint8_t *decode_in_memory(uint8_t *encoded_bytes,
- int32_t *offset, uint32_t *contents) {
- int input_size, charIx;
- uint8_t input[8];
-
- input[0] = *(encoded_bytes++);
- if (input[0] & 0x80)
- input_size = 2;
- else if (input[0] & 0x40)
- input_size = 3;
- else
- input_size = 8;
-
- // we already read one byte..
- charIx = 1;
- while (charIx < input_size) {
- input[charIx++] = *(encoded_bytes++);
- }
-
- // depends on the decoder state!
- decode_bytes(input, input_size, offset, contents);
-
- offs_prev = *offset;
- cont_prev = *contents;
-
- return encoded_bytes;
-}
-
-int retouch_mask_data(uint8_t *binary_object,
- int32_t binary_size,
- int32_t *desired_offset,
- int32_t *retouch_offset) {
- retouch_info_t *r_info;
- prelink_info_t *p_info;
-
- int32_t target_offset = 0;
- if (desired_offset) target_offset = *desired_offset;
-
- int32_t p_offs = binary_size-sizeof(prelink_info_t); // prelink_info_t
- int32_t r_offs = p_offs-sizeof(retouch_info_t); // retouch_info_t
- int32_t b_offs; // retouch data blob
-
- // If not retouched, we say it was a match. This might get invoked on
- // non-retouched binaries, so that's why we need to do this.
- if (retouch_offset != NULL) *retouch_offset = target_offset;
- if (r_offs < 0) return (desired_offset == NULL) ?
- RETOUCH_DATA_NOTAPPLICABLE : RETOUCH_DATA_MATCHED;
- p_info = (prelink_info_t *)(binary_object+p_offs);
- r_info = (retouch_info_t *)(binary_object+r_offs);
- if (strncmp(p_info->tag, "PRE ", 4) ||
- strncmp(r_info->tag, "RETOUCH ", 8))
- return (desired_offset == NULL) ?
- RETOUCH_DATA_NOTAPPLICABLE : RETOUCH_DATA_MATCHED;
-
- b_offs = r_offs-r_info->blob_size;
- if (b_offs < 0) {
- printf("negative binary offset: %d = %d - %d\n",
- b_offs, r_offs, r_info->blob_size);
- return RETOUCH_DATA_ERROR;
- }
- uint8_t *b_ptr = binary_object+b_offs;
-
- // Retouched: let's go through the work then.
- int32_t offset_candidate = target_offset;
- bool offset_set = false, offset_mismatch = false;
- init_compression_state();
- while (b_ptr < (uint8_t *)r_info) {
- int32_t retouch_entry_offset;
- uint32_t *retouch_entry;
- uint32_t retouch_original_value;
-
- b_ptr = decode_in_memory(b_ptr,
- &retouch_entry_offset,
- &retouch_original_value);
- if (retouch_entry_offset < (-1) ||
- retouch_entry_offset >= b_offs) {
- printf("bad retouch_entry_offset: %d", retouch_entry_offset);
- return RETOUCH_DATA_ERROR;
- }
-
- // "-1" means this is the value in prelink_info_t, which also gets
- // randomized.
- if (retouch_entry_offset == -1)
- retouch_entry = (uint32_t *)&(p_info->mmap_addr);
- else
- retouch_entry = (uint32_t *)(binary_object+retouch_entry_offset);
-
- if (desired_offset)
- *retouch_entry = retouch_original_value + target_offset;
-
- // Infer the randomization shift, compare to previously inferred.
- int32_t offset_of_this_entry = (int32_t)(*retouch_entry-
- retouch_original_value);
- if (!offset_set) {
- offset_candidate = offset_of_this_entry;
- offset_set = true;
- } else {
- if (offset_candidate != offset_of_this_entry) {
- offset_mismatch = true;
- printf("offset is mismatched: %d, this entry is %d,"
- " original 0x%x @ 0x%x",
- offset_candidate, offset_of_this_entry,
- retouch_original_value, retouch_entry_offset);
- }
- }
- }
- if (b_ptr > (uint8_t *)r_info) {
- printf("b_ptr went too far: %p, while r_info is %p",
- b_ptr, r_info);
- return RETOUCH_DATA_ERROR;
- }
-
- if (offset_mismatch) return RETOUCH_DATA_MISMATCHED;
- if (retouch_offset != NULL) *retouch_offset = offset_candidate;
- return RETOUCH_DATA_MATCHED;
-}
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