crypto: chacha20poly1305 - Convert to new AEAD interface
This patch converts rfc7539 and rfc7539esp to the new AEAD interface.
The test vectors for rfc7539esp have also been updated to include
the IV.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Martin Willi <martin@strongswan.org>
diff --git a/crypto/chacha20poly1305.c b/crypto/chacha20poly1305.c
index 7b46ed7..8626093 100644
--- a/crypto/chacha20poly1305.c
+++ b/crypto/chacha20poly1305.c
@@ -60,12 +60,16 @@
};
struct chachapoly_req_ctx {
+ struct scatterlist src[2];
+ struct scatterlist dst[2];
/* the key we generate for Poly1305 using Chacha20 */
u8 key[POLY1305_KEY_SIZE];
/* calculated Poly1305 tag */
u8 tag[POLY1305_DIGEST_SIZE];
/* length of data to en/decrypt, without ICV */
unsigned int cryptlen;
+ /* Actual AD, excluding IV */
+ unsigned int assoclen;
union {
struct poly_req poly;
struct chacha_req chacha;
@@ -98,7 +102,9 @@
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
u8 tag[sizeof(rctx->tag)];
- scatterwalk_map_and_copy(tag, req->src, rctx->cryptlen, sizeof(tag), 0);
+ scatterwalk_map_and_copy(tag, req->src,
+ req->assoclen + rctx->cryptlen,
+ sizeof(tag), 0);
if (crypto_memneq(tag, rctx->tag, sizeof(tag)))
return -EBADMSG;
return 0;
@@ -108,7 +114,8 @@
{
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
- scatterwalk_map_and_copy(rctx->tag, req->dst, rctx->cryptlen,
+ scatterwalk_map_and_copy(rctx->tag, req->dst,
+ req->assoclen + rctx->cryptlen,
sizeof(rctx->tag), 1);
return 0;
}
@@ -123,14 +130,24 @@
struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
struct chacha_req *creq = &rctx->u.chacha;
+ struct scatterlist *src, *dst;
int err;
chacha_iv(creq->iv, req, 1);
+ sg_init_table(rctx->src, 2);
+ src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
+ dst = src;
+
+ if (req->src != req->dst) {
+ sg_init_table(rctx->dst, 2);
+ dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
+ }
+
ablkcipher_request_set_callback(&creq->req, aead_request_flags(req),
chacha_decrypt_done, req);
ablkcipher_request_set_tfm(&creq->req, ctx->chacha);
- ablkcipher_request_set_crypt(&creq->req, req->src, req->dst,
+ ablkcipher_request_set_crypt(&creq->req, src, dst,
rctx->cryptlen, creq->iv);
err = crypto_ablkcipher_decrypt(&creq->req);
if (err)
@@ -156,14 +173,15 @@
static int poly_tail(struct aead_request *req)
{
- struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+ struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
struct poly_req *preq = &rctx->u.poly;
__le64 len;
int err;
sg_init_table(preq->src, 1);
- len = cpu_to_le64(req->assoclen);
+ len = cpu_to_le64(rctx->assoclen);
memcpy(&preq->tail.assoclen, &len, sizeof(len));
len = cpu_to_le64(rctx->cryptlen);
memcpy(&preq->tail.cryptlen, &len, sizeof(len));
@@ -228,6 +246,9 @@
if (rctx->cryptlen == req->cryptlen) /* encrypting */
crypt = req->dst;
+ sg_init_table(rctx->src, 2);
+ crypt = scatterwalk_ffwd(rctx->src, crypt, req->assoclen);
+
ahash_request_set_callback(&preq->req, aead_request_flags(req),
poly_cipher_done, req);
ahash_request_set_tfm(&preq->req, ctx->poly);
@@ -253,7 +274,7 @@
unsigned int padlen, bs = POLY1305_BLOCK_SIZE;
int err;
- padlen = (bs - (req->assoclen % bs)) % bs;
+ padlen = (bs - (rctx->assoclen % bs)) % bs;
memset(preq->pad, 0, sizeof(preq->pad));
sg_init_table(preq->src, 1);
sg_set_buf(preq->src, preq->pad, padlen);
@@ -285,7 +306,7 @@
ahash_request_set_callback(&preq->req, aead_request_flags(req),
poly_ad_done, req);
ahash_request_set_tfm(&preq->req, ctx->poly);
- ahash_request_set_crypt(&preq->req, req->assoc, NULL, req->assoclen);
+ ahash_request_set_crypt(&preq->req, req->src, NULL, rctx->assoclen);
err = crypto_ahash_update(&preq->req);
if (err)
@@ -351,11 +372,20 @@
static int poly_genkey(struct aead_request *req)
{
- struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+ struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
struct chacha_req *creq = &rctx->u.chacha;
int err;
+ rctx->assoclen = req->assoclen;
+
+ if (crypto_aead_ivsize(tfm) == 8) {
+ if (rctx->assoclen < 8)
+ return -EINVAL;
+ rctx->assoclen -= 8;
+ }
+
sg_init_table(creq->src, 1);
memset(rctx->key, 0, sizeof(rctx->key));
sg_set_buf(creq->src, rctx->key, sizeof(rctx->key));
@@ -385,14 +415,24 @@
struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
struct chacha_req *creq = &rctx->u.chacha;
+ struct scatterlist *src, *dst;
int err;
chacha_iv(creq->iv, req, 1);
+ sg_init_table(rctx->src, 2);
+ src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
+ dst = src;
+
+ if (req->src != req->dst) {
+ sg_init_table(rctx->dst, 2);
+ dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
+ }
+
ablkcipher_request_set_callback(&creq->req, aead_request_flags(req),
chacha_encrypt_done, req);
ablkcipher_request_set_tfm(&creq->req, ctx->chacha);
- ablkcipher_request_set_crypt(&creq->req, req->src, req->dst,
+ ablkcipher_request_set_crypt(&creq->req, src, dst,
req->cryptlen, creq->iv);
err = crypto_ablkcipher_encrypt(&creq->req);
if (err)
@@ -426,8 +466,6 @@
{
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
- if (req->cryptlen < POLY1305_DIGEST_SIZE)
- return -EINVAL;
rctx->cryptlen = req->cryptlen - POLY1305_DIGEST_SIZE;
/* decrypt call chain:
@@ -476,11 +514,11 @@
return 0;
}
-static int chachapoly_init(struct crypto_tfm *tfm)
+static int chachapoly_init(struct crypto_aead *tfm)
{
- struct crypto_instance *inst = (void *)tfm->__crt_alg;
- struct chachapoly_instance_ctx *ictx = crypto_instance_ctx(inst);
- struct chachapoly_ctx *ctx = crypto_tfm_ctx(tfm);
+ struct aead_instance *inst = aead_alg_instance(tfm);
+ struct chachapoly_instance_ctx *ictx = aead_instance_ctx(inst);
+ struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
struct crypto_ablkcipher *chacha;
struct crypto_ahash *poly;
unsigned long align;
@@ -499,77 +537,88 @@
ctx->poly = poly;
ctx->saltlen = ictx->saltlen;
- align = crypto_tfm_alg_alignmask(tfm);
+ align = crypto_aead_alignmask(tfm);
align &= ~(crypto_tfm_ctx_alignment() - 1);
- crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
- align + offsetof(struct chachapoly_req_ctx, u) +
- max(offsetof(struct chacha_req, req) +
- sizeof(struct ablkcipher_request) +
- crypto_ablkcipher_reqsize(chacha),
- offsetof(struct poly_req, req) +
- sizeof(struct ahash_request) +
- crypto_ahash_reqsize(poly)));
+ crypto_aead_set_reqsize(
+ tfm,
+ align + offsetof(struct chachapoly_req_ctx, u) +
+ max(offsetof(struct chacha_req, req) +
+ sizeof(struct ablkcipher_request) +
+ crypto_ablkcipher_reqsize(chacha),
+ offsetof(struct poly_req, req) +
+ sizeof(struct ahash_request) +
+ crypto_ahash_reqsize(poly)));
return 0;
}
-static void chachapoly_exit(struct crypto_tfm *tfm)
+static void chachapoly_exit(struct crypto_aead *tfm)
{
- struct chachapoly_ctx *ctx = crypto_tfm_ctx(tfm);
+ struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
crypto_free_ahash(ctx->poly);
crypto_free_ablkcipher(ctx->chacha);
}
-static struct crypto_instance *chachapoly_alloc(struct rtattr **tb,
- const char *name,
- unsigned int ivsize)
+static void chachapoly_free(struct aead_instance *inst)
+{
+ struct chachapoly_instance_ctx *ctx = aead_instance_ctx(inst);
+
+ crypto_drop_skcipher(&ctx->chacha);
+ crypto_drop_ahash(&ctx->poly);
+ kfree(inst);
+}
+
+static int chachapoly_create(struct crypto_template *tmpl, struct rtattr **tb,
+ const char *name, unsigned int ivsize)
{
struct crypto_attr_type *algt;
- struct crypto_instance *inst;
+ struct aead_instance *inst;
struct crypto_alg *chacha;
struct crypto_alg *poly;
- struct ahash_alg *poly_ahash;
+ struct hash_alg_common *poly_hash;
struct chachapoly_instance_ctx *ctx;
const char *chacha_name, *poly_name;
int err;
if (ivsize > CHACHAPOLY_IV_SIZE)
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
algt = crypto_get_attr_type(tb);
if (IS_ERR(algt))
- return ERR_CAST(algt);
+ return PTR_ERR(algt);
- if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
- return ERR_PTR(-EINVAL);
+ if ((algt->type ^ (CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_AEAD_NEW)) &
+ algt->mask)
+ return -EINVAL;
chacha_name = crypto_attr_alg_name(tb[1]);
if (IS_ERR(chacha_name))
- return ERR_CAST(chacha_name);
+ return PTR_ERR(chacha_name);
poly_name = crypto_attr_alg_name(tb[2]);
if (IS_ERR(poly_name))
- return ERR_CAST(poly_name);
+ return PTR_ERR(poly_name);
poly = crypto_find_alg(poly_name, &crypto_ahash_type,
CRYPTO_ALG_TYPE_HASH,
CRYPTO_ALG_TYPE_AHASH_MASK);
if (IS_ERR(poly))
- return ERR_CAST(poly);
+ return PTR_ERR(poly);
err = -ENOMEM;
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
if (!inst)
goto out_put_poly;
- ctx = crypto_instance_ctx(inst);
+ ctx = aead_instance_ctx(inst);
ctx->saltlen = CHACHAPOLY_IV_SIZE - ivsize;
- poly_ahash = container_of(poly, struct ahash_alg, halg.base);
- err = crypto_init_ahash_spawn(&ctx->poly, &poly_ahash->halg, inst);
+ poly_hash = __crypto_hash_alg_common(poly);
+ err = crypto_init_ahash_spawn(&ctx->poly, poly_hash,
+ aead_crypto_instance(inst));
if (err)
goto err_free_inst;
- crypto_set_skcipher_spawn(&ctx->chacha, inst);
+ crypto_set_skcipher_spawn(&ctx->chacha, aead_crypto_instance(inst));
err = crypto_grab_skcipher(&ctx->chacha, chacha_name, 0,
crypto_requires_sync(algt->type,
algt->mask));
@@ -587,37 +636,43 @@
goto out_drop_chacha;
err = -ENAMETOOLONG;
- if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"%s(%s,%s)", name, chacha_name,
poly_name) >= CRYPTO_MAX_ALG_NAME)
goto out_drop_chacha;
- if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
"%s(%s,%s)", name, chacha->cra_driver_name,
poly->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
goto out_drop_chacha;
- inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
- inst->alg.cra_flags |= (chacha->cra_flags |
- poly->cra_flags) & CRYPTO_ALG_ASYNC;
- inst->alg.cra_priority = (chacha->cra_priority +
- poly->cra_priority) / 2;
- inst->alg.cra_blocksize = 1;
- inst->alg.cra_alignmask = chacha->cra_alignmask | poly->cra_alignmask;
- inst->alg.cra_type = &crypto_nivaead_type;
- inst->alg.cra_aead.ivsize = ivsize;
- inst->alg.cra_aead.maxauthsize = POLY1305_DIGEST_SIZE;
- inst->alg.cra_ctxsize = sizeof(struct chachapoly_ctx) + ctx->saltlen;
- inst->alg.cra_init = chachapoly_init;
- inst->alg.cra_exit = chachapoly_exit;
- inst->alg.cra_aead.encrypt = chachapoly_encrypt;
- inst->alg.cra_aead.decrypt = chachapoly_decrypt;
- inst->alg.cra_aead.setkey = chachapoly_setkey;
- inst->alg.cra_aead.setauthsize = chachapoly_setauthsize;
- inst->alg.cra_aead.geniv = "seqiv";
+ inst->alg.base.cra_flags = (chacha->cra_flags | poly->cra_flags) &
+ CRYPTO_ALG_ASYNC;
+ inst->alg.base.cra_flags |= CRYPTO_ALG_AEAD_NEW;
+ inst->alg.base.cra_priority = (chacha->cra_priority +
+ poly->cra_priority) / 2;
+ inst->alg.base.cra_blocksize = 1;
+ inst->alg.base.cra_alignmask = chacha->cra_alignmask |
+ poly->cra_alignmask;
+ inst->alg.base.cra_ctxsize = sizeof(struct chachapoly_ctx) +
+ ctx->saltlen;
+ inst->alg.ivsize = ivsize;
+ inst->alg.maxauthsize = POLY1305_DIGEST_SIZE;
+ inst->alg.init = chachapoly_init;
+ inst->alg.exit = chachapoly_exit;
+ inst->alg.encrypt = chachapoly_encrypt;
+ inst->alg.decrypt = chachapoly_decrypt;
+ inst->alg.setkey = chachapoly_setkey;
+ inst->alg.setauthsize = chachapoly_setauthsize;
-out:
+ inst->free = chachapoly_free;
+
+ err = aead_register_instance(tmpl, inst);
+ if (err)
+ goto out_drop_chacha;
+
+out_put_poly:
crypto_mod_put(poly);
- return inst;
+ return err;
out_drop_chacha:
crypto_drop_skcipher(&ctx->chacha);
@@ -625,41 +680,28 @@
crypto_drop_ahash(&ctx->poly);
err_free_inst:
kfree(inst);
-out_put_poly:
- inst = ERR_PTR(err);
- goto out;
+ goto out_put_poly;
}
-static struct crypto_instance *rfc7539_alloc(struct rtattr **tb)
+static int rfc7539_create(struct crypto_template *tmpl, struct rtattr **tb)
{
- return chachapoly_alloc(tb, "rfc7539", 12);
+ return chachapoly_create(tmpl, tb, "rfc7539", 12);
}
-static struct crypto_instance *rfc7539esp_alloc(struct rtattr **tb)
+static int rfc7539esp_create(struct crypto_template *tmpl, struct rtattr **tb)
{
- return chachapoly_alloc(tb, "rfc7539esp", 8);
-}
-
-static void chachapoly_free(struct crypto_instance *inst)
-{
- struct chachapoly_instance_ctx *ctx = crypto_instance_ctx(inst);
-
- crypto_drop_skcipher(&ctx->chacha);
- crypto_drop_ahash(&ctx->poly);
- kfree(inst);
+ return chachapoly_create(tmpl, tb, "rfc7539esp", 8);
}
static struct crypto_template rfc7539_tmpl = {
.name = "rfc7539",
- .alloc = rfc7539_alloc,
- .free = chachapoly_free,
+ .create = rfc7539_create,
.module = THIS_MODULE,
};
static struct crypto_template rfc7539esp_tmpl = {
.name = "rfc7539esp",
- .alloc = rfc7539esp_alloc,
- .free = chachapoly_free,
+ .create = rfc7539esp_create,
.module = THIS_MODULE,
};
@@ -690,6 +732,5 @@
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
MODULE_DESCRIPTION("ChaCha20-Poly1305 AEAD");
-MODULE_ALIAS_CRYPTO("chacha20poly1305");
MODULE_ALIAS_CRYPTO("rfc7539");
MODULE_ALIAS_CRYPTO("rfc7539esp");