mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	[CRYPTO] gcm: Allow block cipher parameter
This patch adds the gcm_base template which takes a block cipher parameter instead of cipher. This allows the user to specify a specific CTR implementation. This also fixes a leak of the cipher algorithm that was previously looked up but never freed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
		
							parent
							
								
									9ffde35a8e
								
							
						
					
					
						commit
						d00aa19b50
					
				
					 1 changed files with 89 additions and 24 deletions
				
			
		
							
								
								
									
										113
									
								
								crypto/gcm.c
									
									
									
									
									
								
							
							
						
						
									
										113
									
								
								crypto/gcm.c
									
									
									
									
									
								
							| 
						 | 
				
			
			@ -413,30 +413,23 @@ static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm)
 | 
			
		|||
	crypto_free_ablkcipher(ctx->ctr);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 | 
			
		||||
static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb,
 | 
			
		||||
						       const char *full_name,
 | 
			
		||||
						       const char *ctr_name)
 | 
			
		||||
{
 | 
			
		||||
	struct crypto_attr_type *algt;
 | 
			
		||||
	struct crypto_instance *inst;
 | 
			
		||||
	struct crypto_alg *ctr;
 | 
			
		||||
	struct crypto_alg *cipher;
 | 
			
		||||
	struct gcm_instance_ctx *ctx;
 | 
			
		||||
	int err;
 | 
			
		||||
	char ctr_name[CRYPTO_MAX_ALG_NAME];
 | 
			
		||||
 | 
			
		||||
	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD);
 | 
			
		||||
	if (err)
 | 
			
		||||
	algt = crypto_get_attr_type(tb);
 | 
			
		||||
	err = PTR_ERR(algt);
 | 
			
		||||
	if (IS_ERR(algt))
 | 
			
		||||
		return ERR_PTR(err);
 | 
			
		||||
 | 
			
		||||
	cipher = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_CIPHER,
 | 
			
		||||
			      CRYPTO_ALG_TYPE_MASK);
 | 
			
		||||
 | 
			
		||||
	inst = ERR_PTR(PTR_ERR(cipher));
 | 
			
		||||
	if (IS_ERR(cipher))
 | 
			
		||||
		return inst;
 | 
			
		||||
 | 
			
		||||
	inst = ERR_PTR(ENAMETOOLONG);
 | 
			
		||||
	if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)",
 | 
			
		||||
		     cipher->cra_name) >= CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
		return inst;
 | 
			
		||||
	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
 | 
			
		||||
		return ERR_PTR(-EINVAL);
 | 
			
		||||
 | 
			
		||||
	ctr = crypto_alg_mod_lookup(ctr_name, CRYPTO_ALG_TYPE_BLKCIPHER,
 | 
			
		||||
				    CRYPTO_ALG_TYPE_MASK);
 | 
			
		||||
| 
						 | 
				
			
			@ -444,7 +437,14 @@ static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 | 
			
		|||
	if (IS_ERR(ctr))
 | 
			
		||||
		return ERR_PTR(PTR_ERR(ctr));
 | 
			
		||||
 | 
			
		||||
	if (cipher->cra_blocksize != 16)
 | 
			
		||||
	/* We only support 16-byte blocks. */
 | 
			
		||||
	if ((ctr->cra_type == &crypto_blkcipher_type ?
 | 
			
		||||
	     ctr->cra_blkcipher.ivsize : ctr->cra_ablkcipher.ivsize) != 16)
 | 
			
		||||
		goto out_put_ctr;
 | 
			
		||||
 | 
			
		||||
	/* Not a stream cipher? */
 | 
			
		||||
	err = -EINVAL;
 | 
			
		||||
	if (ctr->cra_blocksize != 1)
 | 
			
		||||
		goto out_put_ctr;
 | 
			
		||||
 | 
			
		||||
	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
 | 
			
		||||
| 
						 | 
				
			
			@ -453,21 +453,21 @@ static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 | 
			
		|||
		goto out_put_ctr;
 | 
			
		||||
 | 
			
		||||
	err = -ENAMETOOLONG;
 | 
			
		||||
	if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
 | 
			
		||||
		     "gcm(%s)", cipher->cra_name) >= CRYPTO_MAX_ALG_NAME ||
 | 
			
		||||
	    snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 | 
			
		||||
		     "gcm(%s)", cipher->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
	if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
 | 
			
		||||
		     "gcm_base(%s)", ctr->cra_driver_name) >=
 | 
			
		||||
	    CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
		goto err_free_inst;
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
	ctx = crypto_instance_ctx(inst);
 | 
			
		||||
	err = crypto_init_spawn(&ctx->ctr, ctr, inst, CRYPTO_ALG_TYPE_MASK);
 | 
			
		||||
	if (err)
 | 
			
		||||
		goto err_free_inst;
 | 
			
		||||
 | 
			
		||||
	memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME);
 | 
			
		||||
 | 
			
		||||
	inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;
 | 
			
		||||
	inst->alg.cra_priority = ctr->cra_priority;
 | 
			
		||||
	inst->alg.cra_blocksize = 16;
 | 
			
		||||
	inst->alg.cra_blocksize = 1;
 | 
			
		||||
	inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1);
 | 
			
		||||
	inst->alg.cra_type = &crypto_aead_type;
 | 
			
		||||
	inst->alg.cra_aead.ivsize = 16;
 | 
			
		||||
| 
						 | 
				
			
			@ -489,6 +489,29 @@ static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 | 
			
		|||
	goto out;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb)
 | 
			
		||||
{
 | 
			
		||||
	int err;
 | 
			
		||||
	const char *cipher_name;
 | 
			
		||||
	char ctr_name[CRYPTO_MAX_ALG_NAME];
 | 
			
		||||
	char full_name[CRYPTO_MAX_ALG_NAME];
 | 
			
		||||
 | 
			
		||||
	cipher_name = crypto_attr_alg_name(tb[1]);
 | 
			
		||||
	err = PTR_ERR(cipher_name);
 | 
			
		||||
	if (IS_ERR(cipher_name))
 | 
			
		||||
		return ERR_PTR(err);
 | 
			
		||||
 | 
			
		||||
	if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
 | 
			
		||||
	    CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
		return ERR_PTR(-ENAMETOOLONG);
 | 
			
		||||
 | 
			
		||||
	if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >=
 | 
			
		||||
	    CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
		return ERR_PTR(-ENAMETOOLONG);
 | 
			
		||||
 | 
			
		||||
	return crypto_gcm_alloc_common(tb, full_name, ctr_name);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static void crypto_gcm_free(struct crypto_instance *inst)
 | 
			
		||||
{
 | 
			
		||||
	struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst);
 | 
			
		||||
| 
						 | 
				
			
			@ -504,14 +527,55 @@ static struct crypto_template crypto_gcm_tmpl = {
 | 
			
		|||
	.module = THIS_MODULE,
 | 
			
		||||
};
 | 
			
		||||
 | 
			
		||||
static struct crypto_instance *crypto_gcm_base_alloc(struct rtattr **tb)
 | 
			
		||||
{
 | 
			
		||||
	int err;
 | 
			
		||||
	const char *ctr_name;
 | 
			
		||||
	char full_name[CRYPTO_MAX_ALG_NAME];
 | 
			
		||||
 | 
			
		||||
	ctr_name = crypto_attr_alg_name(tb[1]);
 | 
			
		||||
	err = PTR_ERR(ctr_name);
 | 
			
		||||
	if (IS_ERR(ctr_name))
 | 
			
		||||
		return ERR_PTR(err);
 | 
			
		||||
 | 
			
		||||
	if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s)",
 | 
			
		||||
		     ctr_name) >= CRYPTO_MAX_ALG_NAME)
 | 
			
		||||
		return ERR_PTR(-ENAMETOOLONG);
 | 
			
		||||
 | 
			
		||||
	return crypto_gcm_alloc_common(tb, full_name, ctr_name);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static struct crypto_template crypto_gcm_base_tmpl = {
 | 
			
		||||
	.name = "gcm_base",
 | 
			
		||||
	.alloc = crypto_gcm_base_alloc,
 | 
			
		||||
	.free = crypto_gcm_free,
 | 
			
		||||
	.module = THIS_MODULE,
 | 
			
		||||
};
 | 
			
		||||
 | 
			
		||||
static int __init crypto_gcm_module_init(void)
 | 
			
		||||
{
 | 
			
		||||
	return crypto_register_template(&crypto_gcm_tmpl);
 | 
			
		||||
	int err;
 | 
			
		||||
 | 
			
		||||
	err = crypto_register_template(&crypto_gcm_base_tmpl);
 | 
			
		||||
	if (err)
 | 
			
		||||
		goto out;
 | 
			
		||||
 | 
			
		||||
	err = crypto_register_template(&crypto_gcm_tmpl);
 | 
			
		||||
	if (err)
 | 
			
		||||
		goto out_undo_base;
 | 
			
		||||
 | 
			
		||||
out:
 | 
			
		||||
	return err;
 | 
			
		||||
 | 
			
		||||
out_undo_base:
 | 
			
		||||
	crypto_unregister_template(&crypto_gcm_base_tmpl);
 | 
			
		||||
	goto out;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static void __exit crypto_gcm_module_exit(void)
 | 
			
		||||
{
 | 
			
		||||
	crypto_unregister_template(&crypto_gcm_tmpl);
 | 
			
		||||
	crypto_unregister_template(&crypto_gcm_base_tmpl);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
module_init(crypto_gcm_module_init);
 | 
			
		||||
| 
						 | 
				
			
			@ -520,3 +584,4 @@ module_exit(crypto_gcm_module_exit);
 | 
			
		|||
MODULE_LICENSE("GPL");
 | 
			
		||||
MODULE_DESCRIPTION("Galois/Counter Mode");
 | 
			
		||||
MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
 | 
			
		||||
MODULE_ALIAS("gcm_base");
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue