44 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			44 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: MIT
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| /*
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|  * Copyright (C) 2016 The Android Open Source Project
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|  */
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| 
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| #include "avb_hash_descriptor.h"
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| #include "avb_util.h"
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| 
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| bool avb_hash_descriptor_validate_and_byteswap(const AvbHashDescriptor* src,
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|                                                AvbHashDescriptor* dest) {
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|   uint64_t expected_size;
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| 
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|   avb_memcpy(dest, src, sizeof(AvbHashDescriptor));
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| 
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|   if (!avb_descriptor_validate_and_byteswap((const AvbDescriptor*)src,
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|                                             (AvbDescriptor*)dest))
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|     return false;
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| 
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|   if (dest->parent_descriptor.tag != AVB_DESCRIPTOR_TAG_HASH) {
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|     avb_error("Invalid tag for hash descriptor.\n");
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|     return false;
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|   }
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| 
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|   dest->image_size = avb_be64toh(dest->image_size);
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|   dest->partition_name_len = avb_be32toh(dest->partition_name_len);
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|   dest->salt_len = avb_be32toh(dest->salt_len);
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|   dest->digest_len = avb_be32toh(dest->digest_len);
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|   dest->flags = avb_be32toh(dest->flags);
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| 
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|   /* Check that partition_name, salt, and digest are fully contained. */
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|   expected_size = sizeof(AvbHashDescriptor) - sizeof(AvbDescriptor);
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|   if (!avb_safe_add_to(&expected_size, dest->partition_name_len) ||
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|       !avb_safe_add_to(&expected_size, dest->salt_len) ||
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|       !avb_safe_add_to(&expected_size, dest->digest_len)) {
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|     avb_error("Overflow while adding up sizes.\n");
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|     return false;
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|   }
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|   if (expected_size > dest->parent_descriptor.num_bytes_following) {
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|     avb_error("Descriptor payload size overflow.\n");
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|     return false;
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|   }
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|   return true;
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| }
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