summaryrefslogtreecommitdiffstats
path: root/crypto/gcm.c
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/gcm.c')
-rw-r--r--crypto/gcm.c1168
1 files changed, 1168 insertions, 0 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c
new file mode 100644
index 000000000..338ee0769
--- /dev/null
+++ b/crypto/gcm.c
@@ -0,0 +1,1168 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GCM: Galois/Counter Mode.
+ *
+ * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
+ */
+
+#include <crypto/gf128mul.h>
+#include <crypto/internal/aead.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/internal/hash.h>
+#include <crypto/null.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/gcm.h>
+#include <crypto/hash.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+struct gcm_instance_ctx {
+ struct crypto_skcipher_spawn ctr;
+ struct crypto_ahash_spawn ghash;
+};
+
+struct crypto_gcm_ctx {
+ struct crypto_skcipher *ctr;
+ struct crypto_ahash *ghash;
+};
+
+struct crypto_rfc4106_ctx {
+ struct crypto_aead *child;
+ u8 nonce[4];
+};
+
+struct crypto_rfc4106_req_ctx {
+ struct scatterlist src[3];
+ struct scatterlist dst[3];
+ struct aead_request subreq;
+};
+
+struct crypto_rfc4543_instance_ctx {
+ struct crypto_aead_spawn aead;
+};
+
+struct crypto_rfc4543_ctx {
+ struct crypto_aead *child;
+ struct crypto_sync_skcipher *null;
+ u8 nonce[4];
+};
+
+struct crypto_rfc4543_req_ctx {
+ struct aead_request subreq;
+};
+
+struct crypto_gcm_ghash_ctx {
+ unsigned int cryptlen;
+ struct scatterlist *src;
+ int (*complete)(struct aead_request *req, u32 flags);
+};
+
+struct crypto_gcm_req_priv_ctx {
+ u8 iv[16];
+ u8 auth_tag[16];
+ u8 iauth_tag[16];
+ struct scatterlist src[3];
+ struct scatterlist dst[3];
+ struct scatterlist sg;
+ struct crypto_gcm_ghash_ctx ghash_ctx;
+ union {
+ struct ahash_request ahreq;
+ struct skcipher_request skreq;
+ } u;
+};
+
+static struct {
+ u8 buf[16];
+ struct scatterlist sg;
+} *gcm_zeroes;
+
+static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc);
+
+static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx(
+ struct aead_request *req)
+{
+ unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req));
+
+ return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1);
+}
+
+static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
+ struct crypto_ahash *ghash = ctx->ghash;
+ struct crypto_skcipher *ctr = ctx->ctr;
+ struct {
+ be128 hash;
+ u8 iv[16];
+
+ struct crypto_wait wait;
+
+ struct scatterlist sg[1];
+ struct skcipher_request req;
+ } *data;
+ int err;
+
+ crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
+ crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
+ CRYPTO_TFM_REQ_MASK);
+ err = crypto_skcipher_setkey(ctr, key, keylen);
+ if (err)
+ return err;
+
+ data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ crypto_init_wait(&data->wait);
+ sg_init_one(data->sg, &data->hash, sizeof(data->hash));
+ skcipher_request_set_tfm(&data->req, ctr);
+ skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
+ CRYPTO_TFM_REQ_MAY_BACKLOG,
+ crypto_req_done,
+ &data->wait);
+ skcipher_request_set_crypt(&data->req, data->sg, data->sg,
+ sizeof(data->hash), data->iv);
+
+ err = crypto_wait_req(crypto_skcipher_encrypt(&data->req),
+ &data->wait);
+
+ if (err)
+ goto out;
+
+ crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK);
+ crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) &
+ CRYPTO_TFM_REQ_MASK);
+ err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128));
+out:
+ kfree_sensitive(data);
+ return err;
+}
+
+static int crypto_gcm_setauthsize(struct crypto_aead *tfm,
+ unsigned int authsize)
+{
+ return crypto_gcm_check_authsize(authsize);
+}
+
+static void crypto_gcm_init_common(struct aead_request *req)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ __be32 counter = cpu_to_be32(1);
+ struct scatterlist *sg;
+
+ memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag));
+ memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE);
+ memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4);
+
+ sg_init_table(pctx->src, 3);
+ sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag));
+ sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen);
+ if (sg != pctx->src + 1)
+ sg_chain(pctx->src, 2, sg);
+
+ if (req->src != req->dst) {
+ sg_init_table(pctx->dst, 3);
+ sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag));
+ sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen);
+ if (sg != pctx->dst + 1)
+ sg_chain(pctx->dst, 2, sg);
+ }
+}
+
+static void crypto_gcm_init_crypt(struct aead_request *req,
+ unsigned int cryptlen)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead);
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct skcipher_request *skreq = &pctx->u.skreq;
+ struct scatterlist *dst;
+
+ dst = req->src == req->dst ? pctx->src : pctx->dst;
+
+ skcipher_request_set_tfm(skreq, ctx->ctr);
+ skcipher_request_set_crypt(skreq, pctx->src, dst,
+ cryptlen + sizeof(pctx->auth_tag),
+ pctx->iv);
+}
+
+static inline unsigned int gcm_remain(unsigned int len)
+{
+ len &= 0xfU;
+ return len ? 16 - len : 0;
+}
+
+static void gcm_hash_len_done(struct crypto_async_request *areq, int err);
+
+static int gcm_hash_update(struct aead_request *req,
+ crypto_completion_t compl,
+ struct scatterlist *src,
+ unsigned int len, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct ahash_request *ahreq = &pctx->u.ahreq;
+
+ ahash_request_set_callback(ahreq, flags, compl, req);
+ ahash_request_set_crypt(ahreq, src, NULL, len);
+
+ return crypto_ahash_update(ahreq);
+}
+
+static int gcm_hash_remain(struct aead_request *req,
+ unsigned int remain,
+ crypto_completion_t compl, u32 flags)
+{
+ return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags);
+}
+
+static int gcm_hash_len(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct ahash_request *ahreq = &pctx->u.ahreq;
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+ be128 lengths;
+
+ lengths.a = cpu_to_be64(req->assoclen * 8);
+ lengths.b = cpu_to_be64(gctx->cryptlen * 8);
+ memcpy(pctx->iauth_tag, &lengths, 16);
+ sg_init_one(&pctx->sg, pctx->iauth_tag, 16);
+ ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req);
+ ahash_request_set_crypt(ahreq, &pctx->sg,
+ pctx->iauth_tag, sizeof(lengths));
+
+ return crypto_ahash_finup(ahreq);
+}
+
+static int gcm_hash_len_continue(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+
+ return gctx->complete(req, flags);
+}
+
+static void gcm_hash_len_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_len_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags)
+{
+ return gcm_hash_len(req, flags) ?:
+ gcm_hash_len_continue(req, flags);
+}
+
+static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq,
+ int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_crypt_remain_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+ unsigned int remain;
+
+ remain = gcm_remain(gctx->cryptlen);
+ if (remain)
+ return gcm_hash_remain(req, remain,
+ gcm_hash_crypt_remain_done, flags) ?:
+ gcm_hash_crypt_remain_continue(req, flags);
+
+ return gcm_hash_crypt_remain_continue(req, flags);
+}
+
+static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_crypt_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+
+ if (gctx->cryptlen)
+ return gcm_hash_update(req, gcm_hash_crypt_done,
+ gctx->src, gctx->cryptlen, flags) ?:
+ gcm_hash_crypt_continue(req, flags);
+
+ return gcm_hash_crypt_remain_continue(req, flags);
+}
+
+static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq,
+ int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_assoc_remain_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags)
+{
+ unsigned int remain;
+
+ remain = gcm_remain(req->assoclen);
+ if (remain)
+ return gcm_hash_remain(req, remain,
+ gcm_hash_assoc_remain_done, flags) ?:
+ gcm_hash_assoc_remain_continue(req, flags);
+
+ return gcm_hash_assoc_remain_continue(req, flags);
+}
+
+static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_assoc_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash_init_continue(struct aead_request *req, u32 flags)
+{
+ if (req->assoclen)
+ return gcm_hash_update(req, gcm_hash_assoc_done,
+ req->src, req->assoclen, flags) ?:
+ gcm_hash_assoc_continue(req, flags);
+
+ return gcm_hash_assoc_remain_continue(req, flags);
+}
+
+static void gcm_hash_init_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_hash_init_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int gcm_hash(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct ahash_request *ahreq = &pctx->u.ahreq;
+ struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+
+ ahash_request_set_tfm(ahreq, ctx->ghash);
+
+ ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req);
+ return crypto_ahash_init(ahreq) ?:
+ gcm_hash_init_continue(req, flags);
+}
+
+static int gcm_enc_copy_hash(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ u8 *auth_tag = pctx->auth_tag;
+
+ crypto_xor(auth_tag, pctx->iauth_tag, 16);
+ scatterwalk_map_and_copy(auth_tag, req->dst,
+ req->assoclen + req->cryptlen,
+ crypto_aead_authsize(aead), 1);
+ return 0;
+}
+
+static int gcm_encrypt_continue(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+
+ gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst);
+ gctx->cryptlen = req->cryptlen;
+ gctx->complete = gcm_enc_copy_hash;
+
+ return gcm_hash(req, flags);
+}
+
+static void gcm_encrypt_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (err)
+ goto out;
+
+ err = gcm_encrypt_continue(req, 0);
+ if (err == -EINPROGRESS)
+ return;
+
+out:
+ aead_request_complete(req, err);
+}
+
+static int crypto_gcm_encrypt(struct aead_request *req)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct skcipher_request *skreq = &pctx->u.skreq;
+ u32 flags = aead_request_flags(req);
+
+ crypto_gcm_init_common(req);
+ crypto_gcm_init_crypt(req, req->cryptlen);
+ skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req);
+
+ return crypto_skcipher_encrypt(skreq) ?:
+ gcm_encrypt_continue(req, flags);
+}
+
+static int crypto_gcm_verify(struct aead_request *req)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ u8 *auth_tag = pctx->auth_tag;
+ u8 *iauth_tag = pctx->iauth_tag;
+ unsigned int authsize = crypto_aead_authsize(aead);
+ unsigned int cryptlen = req->cryptlen - authsize;
+
+ crypto_xor(auth_tag, iauth_tag, 16);
+ scatterwalk_map_and_copy(iauth_tag, req->src,
+ req->assoclen + cryptlen, authsize, 0);
+ return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0;
+}
+
+static void gcm_decrypt_done(struct crypto_async_request *areq, int err)
+{
+ struct aead_request *req = areq->data;
+
+ if (!err)
+ err = crypto_gcm_verify(req);
+
+ aead_request_complete(req, err);
+}
+
+static int gcm_dec_hash_continue(struct aead_request *req, u32 flags)
+{
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct skcipher_request *skreq = &pctx->u.skreq;
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+
+ crypto_gcm_init_crypt(req, gctx->cryptlen);
+ skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req);
+ return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req);
+}
+
+static int crypto_gcm_decrypt(struct aead_request *req)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req);
+ struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx;
+ unsigned int authsize = crypto_aead_authsize(aead);
+ unsigned int cryptlen = req->cryptlen;
+ u32 flags = aead_request_flags(req);
+
+ cryptlen -= authsize;
+
+ crypto_gcm_init_common(req);
+
+ gctx->src = sg_next(pctx->src);
+ gctx->cryptlen = cryptlen;
+ gctx->complete = gcm_dec_hash_continue;
+
+ return gcm_hash(req, flags);
+}
+
+static int crypto_gcm_init_tfm(struct crypto_aead *tfm)
+{
+ struct aead_instance *inst = aead_alg_instance(tfm);
+ struct gcm_instance_ctx *ictx = aead_instance_ctx(inst);
+ struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
+ struct crypto_skcipher *ctr;
+ struct crypto_ahash *ghash;
+ unsigned long align;
+ int err;
+
+ ghash = crypto_spawn_ahash(&ictx->ghash);
+ if (IS_ERR(ghash))
+ return PTR_ERR(ghash);
+
+ ctr = crypto_spawn_skcipher(&ictx->ctr);
+ err = PTR_ERR(ctr);
+ if (IS_ERR(ctr))
+ goto err_free_hash;
+
+ ctx->ctr = ctr;
+ ctx->ghash = ghash;
+
+ align = crypto_aead_alignmask(tfm);
+ align &= ~(crypto_tfm_ctx_alignment() - 1);
+ crypto_aead_set_reqsize(tfm,
+ align + offsetof(struct crypto_gcm_req_priv_ctx, u) +
+ max(sizeof(struct skcipher_request) +
+ crypto_skcipher_reqsize(ctr),
+ sizeof(struct ahash_request) +
+ crypto_ahash_reqsize(ghash)));
+
+ return 0;
+
+err_free_hash:
+ crypto_free_ahash(ghash);
+ return err;
+}
+
+static void crypto_gcm_exit_tfm(struct crypto_aead *tfm)
+{
+ struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm);
+
+ crypto_free_ahash(ctx->ghash);
+ crypto_free_skcipher(ctx->ctr);
+}
+
+static void crypto_gcm_free(struct aead_instance *inst)
+{
+ struct gcm_instance_ctx *ctx = aead_instance_ctx(inst);
+
+ crypto_drop_skcipher(&ctx->ctr);
+ crypto_drop_ahash(&ctx->ghash);
+ kfree(inst);
+}
+
+static int crypto_gcm_create_common(struct crypto_template *tmpl,
+ struct rtattr **tb,
+ const char *ctr_name,
+ const char *ghash_name)
+{
+ u32 mask;
+ struct aead_instance *inst;
+ struct gcm_instance_ctx *ctx;
+ struct skcipher_alg *ctr;
+ struct hash_alg_common *ghash;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+ ctx = aead_instance_ctx(inst);
+
+ err = crypto_grab_ahash(&ctx->ghash, aead_crypto_instance(inst),
+ ghash_name, 0, mask);
+ if (err)
+ goto err_free_inst;
+ ghash = crypto_spawn_ahash_alg(&ctx->ghash);
+
+ err = -EINVAL;
+ if (strcmp(ghash->base.cra_name, "ghash") != 0 ||
+ ghash->digestsize != 16)
+ goto err_free_inst;
+
+ err = crypto_grab_skcipher(&ctx->ctr, aead_crypto_instance(inst),
+ ctr_name, 0, mask);
+ if (err)
+ goto err_free_inst;
+ ctr = crypto_spawn_skcipher_alg(&ctx->ctr);
+
+ /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */
+ err = -EINVAL;
+ if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 ||
+ crypto_skcipher_alg_ivsize(ctr) != 16 ||
+ ctr->base.cra_blocksize != 1)
+ goto err_free_inst;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "gcm_base(%s,%s)", ctr->base.cra_driver_name,
+ ghash->base.cra_driver_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = (ghash->base.cra_priority +
+ ctr->base.cra_priority) / 2;
+ inst->alg.base.cra_blocksize = 1;
+ inst->alg.base.cra_alignmask = ghash->base.cra_alignmask |
+ ctr->base.cra_alignmask;
+ inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx);
+ inst->alg.ivsize = GCM_AES_IV_SIZE;
+ inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr);
+ inst->alg.maxauthsize = 16;
+ inst->alg.init = crypto_gcm_init_tfm;
+ inst->alg.exit = crypto_gcm_exit_tfm;
+ inst->alg.setkey = crypto_gcm_setkey;
+ inst->alg.setauthsize = crypto_gcm_setauthsize;
+ inst->alg.encrypt = crypto_gcm_encrypt;
+ inst->alg.decrypt = crypto_gcm_decrypt;
+
+ inst->free = crypto_gcm_free;
+
+ err = aead_register_instance(tmpl, inst);
+ if (err) {
+err_free_inst:
+ crypto_gcm_free(inst);
+ }
+ return err;
+}
+
+static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+ const char *cipher_name;
+ char ctr_name[CRYPTO_MAX_ALG_NAME];
+
+ cipher_name = crypto_attr_alg_name(tb[1]);
+ if (IS_ERR(cipher_name))
+ return PTR_ERR(cipher_name);
+
+ if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ return -ENAMETOOLONG;
+
+ return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash");
+}
+
+static int crypto_gcm_base_create(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ const char *ctr_name;
+ const char *ghash_name;
+
+ ctr_name = crypto_attr_alg_name(tb[1]);
+ if (IS_ERR(ctr_name))
+ return PTR_ERR(ctr_name);
+
+ ghash_name = crypto_attr_alg_name(tb[2]);
+ if (IS_ERR(ghash_name))
+ return PTR_ERR(ghash_name);
+
+ return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name);
+}
+
+static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
+ struct crypto_aead *child = ctx->child;
+
+ if (keylen < 4)
+ return -EINVAL;
+
+ keylen -= 4;
+ memcpy(ctx->nonce, key + keylen, 4);
+
+ crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+ crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
+ CRYPTO_TFM_REQ_MASK);
+ return crypto_aead_setkey(child, key, keylen);
+}
+
+static int crypto_rfc4106_setauthsize(struct crypto_aead *parent,
+ unsigned int authsize)
+{
+ struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent);
+ int err;
+
+ err = crypto_rfc4106_check_authsize(authsize);
+ if (err)
+ return err;
+
+ return crypto_aead_setauthsize(ctx->child, authsize);
+}
+
+static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req)
+{
+ struct crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead);
+ struct aead_request *subreq = &rctx->subreq;
+ struct crypto_aead *child = ctx->child;
+ struct scatterlist *sg;
+ u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child),
+ crypto_aead_alignmask(child) + 1);
+
+ scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0);
+
+ memcpy(iv, ctx->nonce, 4);
+ memcpy(iv + 4, req->iv, 8);
+
+ sg_init_table(rctx->src, 3);
+ sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
+ sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen);
+ if (sg != rctx->src + 1)
+ sg_chain(rctx->src, 2, sg);
+
+ if (req->src != req->dst) {
+ sg_init_table(rctx->dst, 3);
+ sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8);
+ sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen);
+ if (sg != rctx->dst + 1)
+ sg_chain(rctx->dst, 2, sg);
+ }
+
+ aead_request_set_tfm(subreq, child);
+ aead_request_set_callback(subreq, req->base.flags, req->base.complete,
+ req->base.data);
+ aead_request_set_crypt(subreq, rctx->src,
+ req->src == req->dst ? rctx->src : rctx->dst,
+ req->cryptlen, iv);
+ aead_request_set_ad(subreq, req->assoclen - 8);
+
+ return subreq;
+}
+
+static int crypto_rfc4106_encrypt(struct aead_request *req)
+{
+ int err;
+
+ err = crypto_ipsec_check_assoclen(req->assoclen);
+ if (err)
+ return err;
+
+ req = crypto_rfc4106_crypt(req);
+
+ return crypto_aead_encrypt(req);
+}
+
+static int crypto_rfc4106_decrypt(struct aead_request *req)
+{
+ int err;
+
+ err = crypto_ipsec_check_assoclen(req->assoclen);
+ if (err)
+ return err;
+
+ req = crypto_rfc4106_crypt(req);
+
+ return crypto_aead_decrypt(req);
+}
+
+static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm)
+{
+ struct aead_instance *inst = aead_alg_instance(tfm);
+ struct crypto_aead_spawn *spawn = aead_instance_ctx(inst);
+ struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
+ struct crypto_aead *aead;
+ unsigned long align;
+
+ aead = crypto_spawn_aead(spawn);
+ if (IS_ERR(aead))
+ return PTR_ERR(aead);
+
+ ctx->child = aead;
+
+ align = crypto_aead_alignmask(aead);
+ align &= ~(crypto_tfm_ctx_alignment() - 1);
+ crypto_aead_set_reqsize(
+ tfm,
+ sizeof(struct crypto_rfc4106_req_ctx) +
+ ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
+ align + 24);
+
+ return 0;
+}
+
+static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm)
+{
+ struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm);
+
+ crypto_free_aead(ctx->child);
+}
+
+static void crypto_rfc4106_free(struct aead_instance *inst)
+{
+ crypto_drop_aead(aead_instance_ctx(inst));
+ kfree(inst);
+}
+
+static int crypto_rfc4106_create(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ u32 mask;
+ struct aead_instance *inst;
+ struct crypto_aead_spawn *spawn;
+ struct aead_alg *alg;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+
+ spawn = aead_instance_ctx(inst);
+ err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+
+ alg = crypto_spawn_aead_alg(spawn);
+
+ err = -EINVAL;
+
+ /* Underlying IV size must be 12. */
+ if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
+ goto err_free_inst;
+
+ /* Not a stream cipher? */
+ if (alg->base.cra_blocksize != 1)
+ goto err_free_inst;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "rfc4106(%s)", alg->base.cra_name) >=
+ CRYPTO_MAX_ALG_NAME ||
+ snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "rfc4106(%s)", alg->base.cra_driver_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = alg->base.cra_priority;
+ inst->alg.base.cra_blocksize = 1;
+ inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+
+ inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx);
+
+ inst->alg.ivsize = GCM_RFC4106_IV_SIZE;
+ inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
+ inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
+
+ inst->alg.init = crypto_rfc4106_init_tfm;
+ inst->alg.exit = crypto_rfc4106_exit_tfm;
+
+ inst->alg.setkey = crypto_rfc4106_setkey;
+ inst->alg.setauthsize = crypto_rfc4106_setauthsize;
+ inst->alg.encrypt = crypto_rfc4106_encrypt;
+ inst->alg.decrypt = crypto_rfc4106_decrypt;
+
+ inst->free = crypto_rfc4106_free;
+
+ err = aead_register_instance(tmpl, inst);
+ if (err) {
+err_free_inst:
+ crypto_rfc4106_free(inst);
+ }
+ return err;
+}
+
+static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
+ struct crypto_aead *child = ctx->child;
+
+ if (keylen < 4)
+ return -EINVAL;
+
+ keylen -= 4;
+ memcpy(ctx->nonce, key + keylen, 4);
+
+ crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK);
+ crypto_aead_set_flags(child, crypto_aead_get_flags(parent) &
+ CRYPTO_TFM_REQ_MASK);
+ return crypto_aead_setkey(child, key, keylen);
+}
+
+static int crypto_rfc4543_setauthsize(struct crypto_aead *parent,
+ unsigned int authsize)
+{
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent);
+
+ if (authsize != 16)
+ return -EINVAL;
+
+ return crypto_aead_setauthsize(ctx->child, authsize);
+}
+
+static int crypto_rfc4543_crypt(struct aead_request *req, bool enc)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
+ struct crypto_rfc4543_req_ctx *rctx = aead_request_ctx(req);
+ struct aead_request *subreq = &rctx->subreq;
+ unsigned int authsize = crypto_aead_authsize(aead);
+ u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
+ crypto_aead_alignmask(ctx->child) + 1);
+ int err;
+
+ if (req->src != req->dst) {
+ err = crypto_rfc4543_copy_src_to_dst(req, enc);
+ if (err)
+ return err;
+ }
+
+ memcpy(iv, ctx->nonce, 4);
+ memcpy(iv + 4, req->iv, 8);
+
+ aead_request_set_tfm(subreq, ctx->child);
+ aead_request_set_callback(subreq, req->base.flags,
+ req->base.complete, req->base.data);
+ aead_request_set_crypt(subreq, req->src, req->dst,
+ enc ? 0 : authsize, iv);
+ aead_request_set_ad(subreq, req->assoclen + req->cryptlen -
+ subreq->cryptlen);
+
+ return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(subreq);
+}
+
+static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
+ unsigned int authsize = crypto_aead_authsize(aead);
+ unsigned int nbytes = req->assoclen + req->cryptlen -
+ (enc ? 0 : authsize);
+ SYNC_SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null);
+
+ skcipher_request_set_sync_tfm(nreq, ctx->null);
+ skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL);
+ skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL);
+
+ return crypto_skcipher_encrypt(nreq);
+}
+
+static int crypto_rfc4543_encrypt(struct aead_request *req)
+{
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ crypto_rfc4543_crypt(req, true);
+}
+
+static int crypto_rfc4543_decrypt(struct aead_request *req)
+{
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ crypto_rfc4543_crypt(req, false);
+}
+
+static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm)
+{
+ struct aead_instance *inst = aead_alg_instance(tfm);
+ struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst);
+ struct crypto_aead_spawn *spawn = &ictx->aead;
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
+ struct crypto_aead *aead;
+ struct crypto_sync_skcipher *null;
+ unsigned long align;
+ int err = 0;
+
+ aead = crypto_spawn_aead(spawn);
+ if (IS_ERR(aead))
+ return PTR_ERR(aead);
+
+ null = crypto_get_default_null_skcipher();
+ err = PTR_ERR(null);
+ if (IS_ERR(null))
+ goto err_free_aead;
+
+ ctx->child = aead;
+ ctx->null = null;
+
+ align = crypto_aead_alignmask(aead);
+ align &= ~(crypto_tfm_ctx_alignment() - 1);
+ crypto_aead_set_reqsize(
+ tfm,
+ sizeof(struct crypto_rfc4543_req_ctx) +
+ ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) +
+ align + GCM_AES_IV_SIZE);
+
+ return 0;
+
+err_free_aead:
+ crypto_free_aead(aead);
+ return err;
+}
+
+static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm)
+{
+ struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm);
+
+ crypto_free_aead(ctx->child);
+ crypto_put_default_null_skcipher();
+}
+
+static void crypto_rfc4543_free(struct aead_instance *inst)
+{
+ struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst);
+
+ crypto_drop_aead(&ctx->aead);
+
+ kfree(inst);
+}
+
+static int crypto_rfc4543_create(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ u32 mask;
+ struct aead_instance *inst;
+ struct aead_alg *alg;
+ struct crypto_rfc4543_instance_ctx *ctx;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+
+ ctx = aead_instance_ctx(inst);
+ err = crypto_grab_aead(&ctx->aead, aead_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+
+ alg = crypto_spawn_aead_alg(&ctx->aead);
+
+ err = -EINVAL;
+
+ /* Underlying IV size must be 12. */
+ if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE)
+ goto err_free_inst;
+
+ /* Not a stream cipher? */
+ if (alg->base.cra_blocksize != 1)
+ goto err_free_inst;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "rfc4543(%s)", alg->base.cra_name) >=
+ CRYPTO_MAX_ALG_NAME ||
+ snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "rfc4543(%s)", alg->base.cra_driver_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = alg->base.cra_priority;
+ inst->alg.base.cra_blocksize = 1;
+ inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+
+ inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx);
+
+ inst->alg.ivsize = GCM_RFC4543_IV_SIZE;
+ inst->alg.chunksize = crypto_aead_alg_chunksize(alg);
+ inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg);
+
+ inst->alg.init = crypto_rfc4543_init_tfm;
+ inst->alg.exit = crypto_rfc4543_exit_tfm;
+
+ inst->alg.setkey = crypto_rfc4543_setkey;
+ inst->alg.setauthsize = crypto_rfc4543_setauthsize;
+ inst->alg.encrypt = crypto_rfc4543_encrypt;
+ inst->alg.decrypt = crypto_rfc4543_decrypt;
+
+ inst->free = crypto_rfc4543_free;
+
+ err = aead_register_instance(tmpl, inst);
+ if (err) {
+err_free_inst:
+ crypto_rfc4543_free(inst);
+ }
+ return err;
+}
+
+static struct crypto_template crypto_gcm_tmpls[] = {
+ {
+ .name = "gcm_base",
+ .create = crypto_gcm_base_create,
+ .module = THIS_MODULE,
+ }, {
+ .name = "gcm",
+ .create = crypto_gcm_create,
+ .module = THIS_MODULE,
+ }, {
+ .name = "rfc4106",
+ .create = crypto_rfc4106_create,
+ .module = THIS_MODULE,
+ }, {
+ .name = "rfc4543",
+ .create = crypto_rfc4543_create,
+ .module = THIS_MODULE,
+ },
+};
+
+static int __init crypto_gcm_module_init(void)
+{
+ int err;
+
+ gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL);
+ if (!gcm_zeroes)
+ return -ENOMEM;
+
+ sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf));
+
+ err = crypto_register_templates(crypto_gcm_tmpls,
+ ARRAY_SIZE(crypto_gcm_tmpls));
+ if (err)
+ kfree(gcm_zeroes);
+
+ return err;
+}
+
+static void __exit crypto_gcm_module_exit(void)
+{
+ kfree(gcm_zeroes);
+ crypto_unregister_templates(crypto_gcm_tmpls,
+ ARRAY_SIZE(crypto_gcm_tmpls));
+}
+
+subsys_initcall(crypto_gcm_module_init);
+module_exit(crypto_gcm_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Galois/Counter Mode");
+MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>");
+MODULE_ALIAS_CRYPTO("gcm_base");
+MODULE_ALIAS_CRYPTO("rfc4106");
+MODULE_ALIAS_CRYPTO("rfc4543");
+MODULE_ALIAS_CRYPTO("gcm");