crypto: seqiv - Add support for new AEAD interface

This patch converts the seqiv IV generator to work with the new
AEAD interface where IV generators are just normal AEAD algorithms.

Full backwards compatibility is paramount at this point since
no users have yet switched over to the new interface.  Nor can
they switch to the new interface until IV generation is fully
supported by it.

So this means we are adding two versions of seqiv alongside the
existing one.  The first one is the one that will be used when
the underlying AEAD algorithm has switched over to the new AEAD
interface.  The second one handles the current case where the
underlying AEAD algorithm still uses the old interface.

Both versions export themselves through the new AEAD interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/Kconfig

@@ -221,6 +221,7 @@ config CRYPTO_SEQIV
 	tristate "Sequence Number IV Generator"
 	select CRYPTO_AEAD
 	select CRYPTO_BLKCIPHER
+	select CRYPTO_NULL
 	select CRYPTO_RNG
 	help
 	  This IV generator generates an IV based on a sequence number by

crypto/aead.c

@@ -378,15 +378,16 @@ static int crypto_grab_nivaead(struct crypto_aead_spawn *spawn,
 	return crypto_grab_spawn(&spawn->base, name, type, mask);
 }
 
-struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
-					 struct rtattr **tb, u32 type,
-					 u32 mask)
+struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
+				       struct rtattr **tb, u32 type, u32 mask)
 {
 	const char *name;
 	struct crypto_aead_spawn *spawn;
 	struct crypto_attr_type *algt;
-	struct crypto_instance *inst;
-	struct crypto_alg *alg;
+	struct aead_instance *inst;
+	struct aead_alg *alg;
+	unsigned int ivsize;
+	unsigned int maxauthsize;
 	int err;
 
 	algt = crypto_get_attr_type(tb);
@@ -405,20 +406,28 @@ struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
 	if (!inst)
 		return ERR_PTR(-ENOMEM);
 
-	spawn = crypto_instance_ctx(inst);
+	spawn = aead_instance_ctx(inst);
 
 	/* Ignore async algorithms if necessary. */
 	mask |= crypto_requires_sync(algt->type, algt->mask);
 
-	crypto_set_aead_spawn(spawn, inst);
+	crypto_set_aead_spawn(spawn, aead_crypto_instance(inst));
 	err = crypto_grab_nivaead(spawn, name, type, mask);
 	if (err)
 		goto err_free_inst;
 
-	alg = crypto_aead_spawn_alg(spawn);
+	alg = crypto_spawn_aead_alg(spawn);
+
+	if (alg->base.cra_aead.encrypt) {
+		ivsize = alg->base.cra_aead.ivsize;
+		maxauthsize = alg->base.cra_aead.maxauthsize;
+	} else {
+		ivsize = alg->ivsize;
+		maxauthsize = alg->maxauthsize;
+	}
 
 	err = -EINVAL;
-	if (!alg->cra_aead.ivsize)
+	if (!ivsize)
 		goto err_drop_alg;
 
 	/*
@@ -427,39 +436,56 @@ struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
 	 * template name and double-check the IV generator.
 	 */
 	if (algt->mask & CRYPTO_ALG_GENIV) {
-		if (strcmp(tmpl->name, alg->cra_aead.geniv))
+		if (!alg->base.cra_aead.encrypt)
+			goto err_drop_alg;
+		if (strcmp(tmpl->name, alg->base.cra_aead.geniv))
 			goto err_drop_alg;
 
-		memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
-		memcpy(inst->alg.cra_driver_name, alg->cra_driver_name,
+		memcpy(inst->alg.base.cra_name, alg->base.cra_name,
 		       CRYPTO_MAX_ALG_NAME);
-	} else {
+		memcpy(inst->alg.base.cra_driver_name,
+		       alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME);
+
+		inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_AEAD |
+					   CRYPTO_ALG_GENIV;
+		inst->alg.base.cra_flags |= alg->base.cra_flags &
+					    CRYPTO_ALG_ASYNC;
+		inst->alg.base.cra_priority = alg->base.cra_priority;
+		inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
+		inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+		inst->alg.base.cra_type = &crypto_aead_type;
+
+		inst->alg.base.cra_aead.ivsize = ivsize;
+		inst->alg.base.cra_aead.maxauthsize = maxauthsize;
+
+		inst->alg.base.cra_aead.setkey = alg->base.cra_aead.setkey;
+		inst->alg.base.cra_aead.setauthsize =
+			alg->base.cra_aead.setauthsize;
+		inst->alg.base.cra_aead.encrypt = alg->base.cra_aead.encrypt;
+		inst->alg.base.cra_aead.decrypt = alg->base.cra_aead.decrypt;
+
+		goto out;
+	}
+
 	err = -ENAMETOOLONG;
-		if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
-			     "%s(%s)", tmpl->name, alg->cra_name) >=
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+		     "%s(%s)", tmpl->name, alg->base.cra_name) >=
 	    CRYPTO_MAX_ALG_NAME)
 		goto err_drop_alg;
-		if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
-			     "%s(%s)", tmpl->name, alg->cra_driver_name) >=
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "%s(%s)", tmpl->name, alg->base.cra_driver_name) >=
 	    CRYPTO_MAX_ALG_NAME)
 		goto err_drop_alg;
-	}
-
-	inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV;
-	inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
-	inst->alg.cra_priority = alg->cra_priority;
-	inst->alg.cra_blocksize = alg->cra_blocksize;
-	inst->alg.cra_alignmask = alg->cra_alignmask;
-	inst->alg.cra_type = &crypto_aead_type;
 
-	inst->alg.cra_aead.ivsize = alg->cra_aead.ivsize;
-	inst->alg.cra_aead.maxauthsize = alg->cra_aead.maxauthsize;
-	inst->alg.cra_aead.geniv = alg->cra_aead.geniv;
+	inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_AEAD;
+	inst->alg.base.cra_flags |= alg->base.cra_flags & CRYPTO_ALG_ASYNC;
+	inst->alg.base.cra_priority = alg->base.cra_priority;
+	inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
+	inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+	inst->alg.base.cra_type = &crypto_new_aead_type;
 
-	inst->alg.cra_aead.setkey = alg->cra_aead.setkey;
-	inst->alg.cra_aead.setauthsize = alg->cra_aead.setauthsize;
-	inst->alg.cra_aead.encrypt = alg->cra_aead.encrypt;
-	inst->alg.cra_aead.decrypt = alg->cra_aead.decrypt;
+	inst->alg.ivsize = ivsize;
+	inst->alg.maxauthsize = maxauthsize;
 
 out:
 	return inst;
@@ -473,9 +499,9 @@ struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
 }
 EXPORT_SYMBOL_GPL(aead_geniv_alloc);
 
-void aead_geniv_free(struct crypto_instance *inst)
+void aead_geniv_free(struct aead_instance *inst)
 {
-	crypto_drop_aead(crypto_instance_ctx(inst));
+	crypto_drop_aead(aead_instance_ctx(inst));
 	kfree(inst);
 }
 EXPORT_SYMBOL_GPL(aead_geniv_free);

include/crypto/internal/aead.h

@@ -117,10 +117,9 @@ static inline struct crypto_aead *crypto_spawn_aead(
 	return crypto_spawn_tfm2(&spawn->base);
 }
 
-struct crypto_instance *aead_geniv_alloc(struct crypto_template *tmpl,
-					 struct rtattr **tb, u32 type,
-					 u32 mask);
-void aead_geniv_free(struct crypto_instance *inst);
+struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
+				       struct rtattr **tb, u32 type, u32 mask);
+void aead_geniv_free(struct aead_instance *inst);
 int aead_geniv_init(struct crypto_tfm *tfm);
 void aead_geniv_exit(struct crypto_tfm *tfm);