122 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			122 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * RSA key extract helper | ||
|  |  * | ||
|  |  * Copyright (c) 2015, Intel Corporation | ||
|  |  * Authors: Tadeusz Struk <tadeusz.struk@intel.com> | ||
|  |  * | ||
|  |  * This program is free software; you can redistribute it and/or modify it | ||
|  |  * under the terms of the GNU General Public License as published by the Free | ||
|  |  * Software Foundation; either version 2 of the License, or (at your option) | ||
|  |  * any later version. | ||
|  |  * | ||
|  |  */ | ||
|  | #include <linux/kernel.h>
 | ||
|  | #include <linux/export.h>
 | ||
|  | #include <linux/err.h>
 | ||
|  | #include <linux/fips.h>
 | ||
|  | #include <crypto/internal/rsa.h>
 | ||
|  | #include "rsakey-asn1.h"
 | ||
|  | 
 | ||
|  | int rsa_get_n(void *context, size_t hdrlen, unsigned char tag, | ||
|  | 	      const void *value, size_t vlen) | ||
|  | { | ||
|  | 	struct rsa_key *key = context; | ||
|  | 
 | ||
|  | 	key->n = mpi_read_raw_data(value, vlen); | ||
|  | 
 | ||
|  | 	if (!key->n) | ||
|  | 		return -ENOMEM; | ||
|  | 
 | ||
|  | 	/* In FIPS mode only allow key size 2K & 3K */ | ||
|  | 	if (fips_enabled && (mpi_get_size(key->n) != 256 || | ||
|  | 			     mpi_get_size(key->n) != 384)) { | ||
|  | 		pr_err("RSA: key size not allowed in FIPS mode\n"); | ||
|  | 		mpi_free(key->n); | ||
|  | 		key->n = NULL; | ||
|  | 		return -EINVAL; | ||
|  | 	} | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | int rsa_get_e(void *context, size_t hdrlen, unsigned char tag, | ||
|  | 	      const void *value, size_t vlen) | ||
|  | { | ||
|  | 	struct rsa_key *key = context; | ||
|  | 
 | ||
|  | 	key->e = mpi_read_raw_data(value, vlen); | ||
|  | 
 | ||
|  | 	if (!key->e) | ||
|  | 		return -ENOMEM; | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | int rsa_get_d(void *context, size_t hdrlen, unsigned char tag, | ||
|  | 	      const void *value, size_t vlen) | ||
|  | { | ||
|  | 	struct rsa_key *key = context; | ||
|  | 
 | ||
|  | 	key->d = mpi_read_raw_data(value, vlen); | ||
|  | 
 | ||
|  | 	if (!key->d) | ||
|  | 		return -ENOMEM; | ||
|  | 
 | ||
|  | 	/* In FIPS mode only allow key size 2K & 3K */ | ||
|  | 	if (fips_enabled && (mpi_get_size(key->d) != 256 || | ||
|  | 			     mpi_get_size(key->d) != 384)) { | ||
|  | 		pr_err("RSA: key size not allowed in FIPS mode\n"); | ||
|  | 		mpi_free(key->d); | ||
|  | 		key->d = NULL; | ||
|  | 		return -EINVAL; | ||
|  | 	} | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | static void free_mpis(struct rsa_key *key) | ||
|  | { | ||
|  | 	mpi_free(key->n); | ||
|  | 	mpi_free(key->e); | ||
|  | 	mpi_free(key->d); | ||
|  | 	key->n = NULL; | ||
|  | 	key->e = NULL; | ||
|  | 	key->d = NULL; | ||
|  | } | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * rsa_free_key() - frees rsa key allocated by rsa_parse_key() | ||
|  |  * | ||
|  |  * @rsa_key:	struct rsa_key key representation | ||
|  |  */ | ||
|  | void rsa_free_key(struct rsa_key *key) | ||
|  | { | ||
|  | 	free_mpis(key); | ||
|  | } | ||
|  | EXPORT_SYMBOL_GPL(rsa_free_key); | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * rsa_parse_key() - extracts an rsa key from BER encoded buffer | ||
|  |  *		     and stores it in the provided struct rsa_key | ||
|  |  * | ||
|  |  * @rsa_key:	struct rsa_key key representation | ||
|  |  * @key:	key in BER format | ||
|  |  * @key_len:	length of key | ||
|  |  * | ||
|  |  * Return:	0 on success or error code in case of error | ||
|  |  */ | ||
|  | int rsa_parse_key(struct rsa_key *rsa_key, const void *key, | ||
|  | 		  unsigned int key_len) | ||
|  | { | ||
|  | 	int ret; | ||
|  | 
 | ||
|  | 	free_mpis(rsa_key); | ||
|  | 	ret = asn1_ber_decoder(&rsakey_decoder, rsa_key, key, key_len); | ||
|  | 	if (ret < 0) | ||
|  | 		goto error; | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | error: | ||
|  | 	free_mpis(rsa_key); | ||
|  | 	return ret; | ||
|  | } | ||
|  | EXPORT_SYMBOL_GPL(rsa_parse_key); |