1 files changed, 400 insertions, 0 deletions

diff --git a/crypto/authenc.c b/crypto/authenc.c
new file mode 100644
index 000000000000..86b3ac88eab7
--- /dev/null
+++ b/crypto/authenc.c
@@ -0,0 +1,400 @@
+/*
+ * Authenc: Simple AEAD wrapper for IPsec
+ *
+ * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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 <crypto/algapi.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "scatterwalk.h"
+
+struct authenc_instance_ctx {
+        struct crypto_spawn auth;
+        struct crypto_spawn enc;
+
+        unsigned int authsize;
+        unsigned int enckeylen;
+};
+
+struct crypto_authenc_ctx {
+        spinlock_t auth_lock;
+        struct crypto_hash *auth;
+        struct crypto_ablkcipher *enc;
+};
+
+static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
+                                 unsigned int keylen)
+{
+        struct authenc_instance_ctx *ictx =
+                crypto_instance_ctx(crypto_aead_alg_instance(authenc));
+        unsigned int enckeylen = ictx->enckeylen;
+        unsigned int authkeylen;
+        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
+        struct crypto_hash *auth = ctx->auth;
+        struct crypto_ablkcipher *enc = ctx->enc;
+        int err = -EINVAL;
+
+        if (keylen < enckeylen) {
+                crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN);
+                goto out;
+        }
+        authkeylen = keylen - enckeylen;
+
+        crypto_hash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
+        crypto_hash_set_flags(auth, crypto_aead_get_flags(authenc) &
+                                    CRYPTO_TFM_REQ_MASK);
+        err = crypto_hash_setkey(auth, key, authkeylen);
+        crypto_aead_set_flags(authenc, crypto_hash_get_flags(auth) &
+                                       CRYPTO_TFM_RES_MASK);
+
+        if (err)
+                goto out;
+
+        crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
+        crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) &
+                                         CRYPTO_TFM_REQ_MASK);
+        err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen);
+        crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) &
+                                       CRYPTO_TFM_RES_MASK);
+
+out:
+        return err;
+}
+
+static int crypto_authenc_hash(struct aead_request *req)
+{
+        struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+        struct authenc_instance_ctx *ictx =
+                crypto_instance_ctx(crypto_aead_alg_instance(authenc));
+        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
+        struct crypto_hash *auth = ctx->auth;
+        struct hash_desc desc = {
+                .tfm = auth,
+        };
+        u8 *hash = aead_request_ctx(req);
+        struct scatterlist *dst;
+        unsigned int cryptlen;
+        int err;
+
+        hash = (u8 *)ALIGN((unsigned long)hash + crypto_hash_alignmask(auth), 
+                           crypto_hash_alignmask(auth) + 1);
+
+        spin_lock_bh(&ctx->auth_lock);
+        err = crypto_hash_init(&desc);
+        if (err)
+                goto auth_unlock;
+
+        err = crypto_hash_update(&desc, req->assoc, req->assoclen);
+        if (err)
+                goto auth_unlock;
+
+        cryptlen = req->cryptlen;
+        dst = req->dst;
+        err = crypto_hash_update(&desc, dst, cryptlen);
+        if (err)
+                goto auth_unlock;
+
+        err = crypto_hash_final(&desc, hash);
+auth_unlock:
+        spin_unlock_bh(&ctx->auth_lock);
+
+        if (err)
+                return err;
+
+        scatterwalk_map_and_copy(hash, dst, cryptlen, ictx->authsize, 1);
+        return 0;
+}
+
+static void crypto_authenc_encrypt_done(struct crypto_async_request *req,
+                                        int err)
+{
+        if (!err)
+                err = crypto_authenc_hash(req->data);
+
+        aead_request_complete(req->data, err);
+}
+
+static int crypto_authenc_encrypt(struct aead_request *req)
+{
+        struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
+        struct ablkcipher_request *abreq = aead_request_ctx(req);
+        int err;
+
+        ablkcipher_request_set_tfm(abreq, ctx->enc);
+        ablkcipher_request_set_callback(abreq, aead_request_flags(req),
+                                        crypto_authenc_encrypt_done, req);
+        ablkcipher_request_set_crypt(abreq, req->src, req->dst, req->cryptlen,
+                                     req->iv);
+
+        err = crypto_ablkcipher_encrypt(abreq);
+        if (err)
+                return err;
+
+        return crypto_authenc_hash(req);
+}
+
+static int crypto_authenc_verify(struct aead_request *req)
+{
+        struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+        struct authenc_instance_ctx *ictx =
+                crypto_instance_ctx(crypto_aead_alg_instance(authenc));
+        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
+        struct crypto_hash *auth = ctx->auth;
+        struct hash_desc desc = {
+                .tfm = auth,
+                .flags = aead_request_flags(req),
+        };
+        u8 *ohash = aead_request_ctx(req);
+        u8 *ihash;
+        struct scatterlist *src;
+        unsigned int cryptlen;
+        unsigned int authsize;
+        int err;
+
+        ohash = (u8 *)ALIGN((unsigned long)ohash + crypto_hash_alignmask(auth), 
+                            crypto_hash_alignmask(auth) + 1);
+        ihash = ohash + crypto_hash_digestsize(auth);
+
+        spin_lock_bh(&ctx->auth_lock);
+        err = crypto_hash_init(&desc);
+        if (err)
+                goto auth_unlock;
+
+        err = crypto_hash_update(&desc, req->assoc, req->assoclen);
+        if (err)
+                goto auth_unlock;
+
+        cryptlen = req->cryptlen;
+        src = req->src;
+        err = crypto_hash_update(&desc, src, cryptlen);
+        if (err)
+                goto auth_unlock;
+
+        err = crypto_hash_final(&desc, ohash);
+auth_unlock:
+        spin_unlock_bh(&ctx->auth_lock);
+
+        if (err)
+                return err;
+
+        authsize = ictx->authsize;
+        scatterwalk_map_and_copy(ihash, src, cryptlen, authsize, 0);
+        return memcmp(ihash, ohash, authsize) ? -EINVAL : 0;
+}
+
+static void crypto_authenc_decrypt_done(struct crypto_async_request *req,
+                                        int err)
+{
+        aead_request_complete(req->data, err);
+}
+
+static int crypto_authenc_decrypt(struct aead_request *req)
+{
+        struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
+        struct ablkcipher_request *abreq = aead_request_ctx(req);
+        int err;
+
+        err = crypto_authenc_verify(req);
+        if (err)
+                return err;
+
+        ablkcipher_request_set_tfm(abreq, ctx->enc);
+        ablkcipher_request_set_callback(abreq, aead_request_flags(req),
+                                        crypto_authenc_decrypt_done, req);
+        ablkcipher_request_set_crypt(abreq, req->src, req->dst, req->cryptlen,
+                                     req->iv);
+
+        return crypto_ablkcipher_decrypt(abreq);
+}
+
+static int crypto_authenc_init_tfm(struct crypto_tfm *tfm)
+{
+        struct crypto_instance *inst = (void *)tfm->__crt_alg;
+        struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst);
+        struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
+        struct crypto_hash *auth;
+        struct crypto_ablkcipher *enc;
+        unsigned int digestsize;
+        int err;
+
+        auth = crypto_spawn_hash(&ictx->auth);
+        if (IS_ERR(auth))
+                return PTR_ERR(auth);
+
+        err = -EINVAL;
+        digestsize = crypto_hash_digestsize(auth);
+        if (ictx->authsize > digestsize)
+                goto err_free_hash;
+
+        enc = crypto_spawn_ablkcipher(&ictx->enc);
+        err = PTR_ERR(enc);
+        if (IS_ERR(enc))
+                goto err_free_hash;
+
+        ctx->auth = auth;
+        ctx->enc = enc;
+        tfm->crt_aead.reqsize = max_t(unsigned int,
+                                      (crypto_hash_alignmask(auth) &
+                                       ~(crypto_tfm_ctx_alignment() - 1)) +
+                                      digestsize * 2,
+                                      sizeof(struct ablkcipher_request) +
+                                      crypto_ablkcipher_reqsize(enc));
+
+        spin_lock_init(&ctx->auth_lock);
+
+        return 0;
+
+err_free_hash:
+        crypto_free_hash(auth);
+        return err;
+}
+
+static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm)
+{
+        struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm);
+
+        crypto_free_hash(ctx->auth);
+        crypto_free_ablkcipher(ctx->enc);
+}
+
+static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb)
+{
+        struct crypto_instance *inst;
+        struct crypto_alg *auth;
+        struct crypto_alg *enc;
+        struct authenc_instance_ctx *ctx;
+        unsigned int authsize;
+        unsigned int enckeylen;
+        int err;
+
+        err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD);
+        if (err)
+                return ERR_PTR(err);
+
+        auth = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
+                               CRYPTO_ALG_TYPE_HASH_MASK);
+        if (IS_ERR(auth))
+                return ERR_PTR(PTR_ERR(auth));
+
+        err = crypto_attr_u32(tb[2], &authsize);
+        inst = ERR_PTR(err);
+        if (err)
+                goto out_put_auth;
+
+        enc = crypto_attr_alg(tb[3], CRYPTO_ALG_TYPE_BLKCIPHER,
+                              CRYPTO_ALG_TYPE_MASK);
+        inst = ERR_PTR(PTR_ERR(enc));
+        if (IS_ERR(enc))
+                goto out_put_auth;
+
+        err = crypto_attr_u32(tb[4], &enckeylen);
+        if (err)
+                goto out_put_enc;
+
+        inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+        err = -ENOMEM;
+        if (!inst)
+                goto out_put_enc;
+
+        err = -ENAMETOOLONG;
+        if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
+                     "authenc(%s, %u, %s, %u)", auth->cra_name, authsize,
+                     enc->cra_name, enckeylen) >= CRYPTO_MAX_ALG_NAME)
+                goto err_free_inst;
+
+        if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+                     "authenc(%s, %u, %s, %u)", auth->cra_driver_name,
+                     authsize, enc->cra_driver_name, enckeylen) >=
+            CRYPTO_MAX_ALG_NAME)
+                goto err_free_inst;
+
+        ctx = crypto_instance_ctx(inst);
+        ctx->authsize = authsize;
+        ctx->enckeylen = enckeylen;
+
+        err = crypto_init_spawn(&ctx->auth, auth, inst, CRYPTO_ALG_TYPE_MASK);
+        if (err)
+                goto err_free_inst;
+
+        err = crypto_init_spawn(&ctx->enc, enc, inst, CRYPTO_ALG_TYPE_MASK);
+        if (err)
+                goto err_drop_auth;
+
+        inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_ASYNC;
+        inst->alg.cra_priority = enc->cra_priority * 10 + auth->cra_priority;
+        inst->alg.cra_blocksize = enc->cra_blocksize;
+        inst->alg.cra_alignmask = max(auth->cra_alignmask, enc->cra_alignmask);
+        inst->alg.cra_type = &crypto_aead_type;
+
+        inst->alg.cra_aead.ivsize = enc->cra_blkcipher.ivsize;
+        inst->alg.cra_aead.authsize = authsize;
+
+        inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx);
+
+        inst->alg.cra_init = crypto_authenc_init_tfm;
+        inst->alg.cra_exit = crypto_authenc_exit_tfm;
+
+        inst->alg.cra_aead.setkey = crypto_authenc_setkey;
+        inst->alg.cra_aead.encrypt = crypto_authenc_encrypt;
+        inst->alg.cra_aead.decrypt = crypto_authenc_decrypt;
+
+out:
+        crypto_mod_put(enc);
+out_put_auth:
+        crypto_mod_put(auth);
+        return inst;
+
+err_drop_auth:
+        crypto_drop_spawn(&ctx->auth);
+err_free_inst:
+        kfree(inst);
+out_put_enc:
+        inst = ERR_PTR(err);
+        goto out;
+}
+
+static void crypto_authenc_free(struct crypto_instance *inst)
+{
+        struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst);
+
+        crypto_drop_spawn(&ctx->enc);
+        crypto_drop_spawn(&ctx->auth);
+        kfree(inst);
+}
+
+static struct crypto_template crypto_authenc_tmpl = {
+        .name = "authenc",
+        .alloc = crypto_authenc_alloc,
+        .free = crypto_authenc_free,
+        .module = THIS_MODULE,
+};
+
+static int __init crypto_authenc_module_init(void)
+{
+        return crypto_register_template(&crypto_authenc_tmpl);
+}
+
+static void __exit crypto_authenc_module_exit(void)
+{
+        crypto_unregister_template(&crypto_authenc_tmpl);
+}
+
+module_init(crypto_authenc_module_init);
+module_exit(crypto_authenc_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec");