60 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * purgatory: Runs between two kernels
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|  *
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|  * Copyright (C) 2014 Red Hat Inc.
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|  *
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|  * Author:
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|  *       Vivek Goyal <vgoyal@redhat.com>
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|  *
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|  * This source code is licensed under the GNU General Public License,
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|  * Version 2.  See the file COPYING for more details.
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|  */
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| 
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| #include <linux/bug.h>
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| #include <crypto/sha.h>
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| #include <asm/purgatory.h>
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| 
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| #include "../boot/string.h"
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| 
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| u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(.kexec-purgatory);
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| 
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| struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(.kexec-purgatory);
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| 
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| static int verify_sha256_digest(void)
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| {
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| 	struct kexec_sha_region *ptr, *end;
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| 	u8 digest[SHA256_DIGEST_SIZE];
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| 	struct sha256_state sctx;
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| 
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| 	sha256_init(&sctx);
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| 	end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
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| 
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| 	for (ptr = purgatory_sha_regions; ptr < end; ptr++)
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| 		sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
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| 
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| 	sha256_final(&sctx, digest);
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| 
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| 	if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)))
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| 		return 1;
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| 
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| 	return 0;
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| }
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| 
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| void purgatory(void)
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| {
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| 	int ret;
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| 
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| 	ret = verify_sha256_digest();
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| 	if (ret) {
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| 		/* loop forever */
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| 		for (;;)
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| 			;
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| 	}
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| }
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| 
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| /*
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|  * Defined in order to reuse memcpy() and memset() from
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|  * arch/x86/boot/compressed/string.c
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|  */
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| void warn(const char *msg) {}
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