diff --git a/crypto/gcm.c b/crypto/gcm.c index d539f5e56879..e70afd0c73dd 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -9,6 +9,7 @@ */ #include +#include #include #include #include @@ -27,6 +28,11 @@ struct crypto_gcm_ctx { struct gf128mul_4k *gf128; }; +struct crypto_rfc4106_ctx { + struct crypto_aead *child; + u8 nonce[4]; +}; + struct crypto_gcm_ghash_ctx { u32 bytes; u32 flags; @@ -240,6 +246,25 @@ out: return err; } +static int crypto_gcm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 4: + case 8: + case 12: + case 13: + case 14: + case 15: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + static void crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req, struct aead_request *req, unsigned int cryptlen) @@ -472,6 +497,7 @@ static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, inst->alg.cra_init = crypto_gcm_init_tfm; inst->alg.cra_exit = crypto_gcm_exit_tfm; inst->alg.cra_aead.setkey = crypto_gcm_setkey; + inst->alg.cra_aead.setauthsize = crypto_gcm_setauthsize; inst->alg.cra_aead.encrypt = crypto_gcm_encrypt; inst->alg.cra_aead.decrypt = crypto_gcm_decrypt; @@ -549,6 +575,211 @@ static struct crypto_template crypto_gcm_base_tmpl = { .module = THIS_MODULE, }; +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; + int err; + + 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); + err = crypto_aead_setkey(child, key, keylen); + crypto_aead_set_flags(parent, crypto_aead_get_flags(child) & + CRYPTO_TFM_RES_MASK); + + return err; +} + +static int crypto_rfc4106_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); + + switch (authsize) { + case 8: + case 12: + case 16: + break; + default: + return -EINVAL; + } + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req) +{ + struct aead_request *subreq = aead_request_ctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_aead *child = ctx->child; + u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), + crypto_aead_alignmask(child) + 1); + + memcpy(iv, ctx->nonce, 4); + memcpy(iv + 4, req->iv, 8); + + 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, req->src, req->dst, req->cryptlen, iv); + aead_request_set_assoc(subreq, req->assoc, req->assoclen); + + return subreq; +} + +static int crypto_rfc4106_encrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_encrypt(req); +} + +static int crypto_rfc4106_decrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4106_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct crypto_aead_spawn *spawn = crypto_instance_ctx(inst); + struct crypto_rfc4106_ctx *ctx = crypto_tfm_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); + tfm->crt_aead.reqsize = sizeof(struct aead_request) + + ALIGN(crypto_aead_reqsize(aead), + crypto_tfm_ctx_alignment()) + + align + 16; + + return 0; +} + +static void crypto_rfc4106_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static struct crypto_instance *crypto_rfc4106_alloc(struct rtattr **tb) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_aead_spawn *spawn; + struct crypto_alg *alg; + const char *ccm_name; + int err; + + algt = crypto_get_attr_type(tb); + err = PTR_ERR(algt); + if (IS_ERR(algt)) + return ERR_PTR(err); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + ccm_name = crypto_attr_alg_name(tb[1]); + err = PTR_ERR(ccm_name); + if (IS_ERR(ccm_name)) + return ERR_PTR(err); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return ERR_PTR(-ENOMEM); + + spawn = crypto_instance_ctx(inst); + crypto_set_aead_spawn(spawn, inst); + err = crypto_grab_aead(spawn, ccm_name, 0, + crypto_requires_sync(algt->type, algt->mask)); + if (err) + goto out_free_inst; + + alg = crypto_aead_spawn_alg(spawn); + + err = -EINVAL; + + /* We only support 16-byte blocks. */ + if (alg->cra_aead.ivsize != 16) + goto out_drop_alg; + + /* Not a stream cipher? */ + if (alg->cra_blocksize != 1) + goto out_drop_alg; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_drop_alg; + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; + inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.cra_priority = alg->cra_priority; + inst->alg.cra_blocksize = 1; + inst->alg.cra_alignmask = alg->cra_alignmask; + inst->alg.cra_type = &crypto_nivaead_type; + + inst->alg.cra_aead.ivsize = 8; + inst->alg.cra_aead.maxauthsize = 16; + + inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx); + + inst->alg.cra_init = crypto_rfc4106_init_tfm; + inst->alg.cra_exit = crypto_rfc4106_exit_tfm; + + inst->alg.cra_aead.setkey = crypto_rfc4106_setkey; + inst->alg.cra_aead.setauthsize = crypto_rfc4106_setauthsize; + inst->alg.cra_aead.encrypt = crypto_rfc4106_encrypt; + inst->alg.cra_aead.decrypt = crypto_rfc4106_decrypt; + + inst->alg.cra_aead.geniv = "seqiv"; + +out: + return inst; + +out_drop_alg: + crypto_drop_aead(spawn); +out_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} + +static void crypto_rfc4106_free(struct crypto_instance *inst) +{ + crypto_drop_spawn(crypto_instance_ctx(inst)); + kfree(inst); +} + +static struct crypto_template crypto_rfc4106_tmpl = { + .name = "rfc4106", + .alloc = crypto_rfc4106_alloc, + .free = crypto_rfc4106_free, + .module = THIS_MODULE, +}; + static int __init crypto_gcm_module_init(void) { int err; @@ -561,9 +792,15 @@ static int __init crypto_gcm_module_init(void) if (err) goto out_undo_base; + err = crypto_register_template(&crypto_rfc4106_tmpl); + if (err) + goto out_undo_gcm; + out: return err; +out_undo_gcm: + crypto_unregister_template(&crypto_gcm_tmpl); out_undo_base: crypto_unregister_template(&crypto_gcm_base_tmpl); goto out; @@ -571,6 +808,7 @@ out_undo_base: static void __exit crypto_gcm_module_exit(void) { + crypto_unregister_template(&crypto_rfc4106_tmpl); crypto_unregister_template(&crypto_gcm_tmpl); crypto_unregister_template(&crypto_gcm_base_tmpl); } @@ -582,3 +820,4 @@ MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Galois/Counter Mode"); MODULE_AUTHOR("Mikko Herranen "); MODULE_ALIAS("gcm_base"); +MODULE_ALIAS("rfc4106");