diff options
Diffstat (limited to 'crypto/aead.c')
-rw-r--r-- | crypto/aead.c | 437 |
1 files changed, 437 insertions, 0 deletions
diff --git a/crypto/aead.c b/crypto/aead.c new file mode 100644 index 000000000..9688ada13 --- /dev/null +++ b/crypto/aead.c @@ -0,0 +1,437 @@ +/* + * AEAD: Authenticated Encryption with Associated Data + * + * This file provides API support for AEAD algorithms. + * + * Copyright (c) 2007-2015 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/internal/geniv.h> +#include <crypto/internal/rng.h> +#include <crypto/null.h> +#include <crypto/scatterwalk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/rtnetlink.h> +#include <linux/slab.h> +#include <linux/seq_file.h> +#include <linux/cryptouser.h> +#include <linux/compiler.h> +#include <net/netlink.h> + +#include "internal.h" + +static int setkey_unaligned(struct crypto_aead *tfm, const u8 *key, + unsigned int keylen) +{ + unsigned long alignmask = crypto_aead_alignmask(tfm); + int ret; + u8 *buffer, *alignbuffer; + unsigned long absize; + + absize = keylen + alignmask; + buffer = kmalloc(absize, GFP_ATOMIC); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + ret = crypto_aead_alg(tfm)->setkey(tfm, alignbuffer, keylen); + memset(alignbuffer, 0, keylen); + kfree(buffer); + return ret; +} + +int crypto_aead_setkey(struct crypto_aead *tfm, + const u8 *key, unsigned int keylen) +{ + unsigned long alignmask = crypto_aead_alignmask(tfm); + int err; + + if ((unsigned long)key & alignmask) + err = setkey_unaligned(tfm, key, keylen); + else + err = crypto_aead_alg(tfm)->setkey(tfm, key, keylen); + + if (unlikely(err)) { + crypto_aead_set_flags(tfm, CRYPTO_TFM_NEED_KEY); + return err; + } + + crypto_aead_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); + return 0; +} +EXPORT_SYMBOL_GPL(crypto_aead_setkey); + +int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize) +{ + int err; + + if (authsize > crypto_aead_maxauthsize(tfm)) + return -EINVAL; + + if (crypto_aead_alg(tfm)->setauthsize) { + err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize); + if (err) + return err; + } + + tfm->authsize = authsize; + return 0; +} +EXPORT_SYMBOL_GPL(crypto_aead_setauthsize); + +static void crypto_aead_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_aead *aead = __crypto_aead_cast(tfm); + struct aead_alg *alg = crypto_aead_alg(aead); + + alg->exit(aead); +} + +static int crypto_aead_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_aead *aead = __crypto_aead_cast(tfm); + struct aead_alg *alg = crypto_aead_alg(aead); + + crypto_aead_set_flags(aead, CRYPTO_TFM_NEED_KEY); + + aead->authsize = alg->maxauthsize; + + if (alg->exit) + aead->base.exit = crypto_aead_exit_tfm; + + if (alg->init) + return alg->init(aead); + + return 0; +} + +#ifdef CONFIG_NET +static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + struct crypto_report_aead raead; + struct aead_alg *aead = container_of(alg, struct aead_alg, base); + + strncpy(raead.type, "aead", sizeof(raead.type)); + strncpy(raead.geniv, "<none>", sizeof(raead.geniv)); + + raead.blocksize = alg->cra_blocksize; + raead.maxauthsize = aead->maxauthsize; + raead.ivsize = aead->ivsize; + + if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD, + sizeof(struct crypto_report_aead), &raead)) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -EMSGSIZE; +} +#else +static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg) +{ + return -ENOSYS; +} +#endif + +static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg) + __maybe_unused; +static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg) +{ + struct aead_alg *aead = container_of(alg, struct aead_alg, base); + + seq_printf(m, "type : aead\n"); + seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? + "yes" : "no"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "ivsize : %u\n", aead->ivsize); + seq_printf(m, "maxauthsize : %u\n", aead->maxauthsize); + seq_printf(m, "geniv : <none>\n"); +} + +static void crypto_aead_free_instance(struct crypto_instance *inst) +{ + struct aead_instance *aead = aead_instance(inst); + + if (!aead->free) { + inst->tmpl->free(inst); + return; + } + + aead->free(aead); +} + +static const struct crypto_type crypto_aead_type = { + .extsize = crypto_alg_extsize, + .init_tfm = crypto_aead_init_tfm, + .free = crypto_aead_free_instance, +#ifdef CONFIG_PROC_FS + .show = crypto_aead_show, +#endif + .report = crypto_aead_report, + .maskclear = ~CRYPTO_ALG_TYPE_MASK, + .maskset = CRYPTO_ALG_TYPE_MASK, + .type = CRYPTO_ALG_TYPE_AEAD, + .tfmsize = offsetof(struct crypto_aead, base), +}; + +static int aead_geniv_setkey(struct crypto_aead *tfm, + const u8 *key, unsigned int keylen) +{ + struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm); + + return crypto_aead_setkey(ctx->child, key, keylen); +} + +static int aead_geniv_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm); + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +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 aead_instance *inst; + struct aead_alg *alg; + unsigned int ivsize; + unsigned int maxauthsize; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return ERR_CAST(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(name)) + return ERR_CAST(name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return ERR_PTR(-ENOMEM); + + spawn = aead_instance_ctx(inst); + + /* Ignore async algorithms if necessary. */ + mask |= crypto_requires_sync(algt->type, algt->mask); + + crypto_set_aead_spawn(spawn, aead_crypto_instance(inst)); + err = crypto_grab_aead(spawn, name, type, mask); + if (err) + goto err_free_inst; + + alg = crypto_spawn_aead_alg(spawn); + + ivsize = crypto_aead_alg_ivsize(alg); + maxauthsize = crypto_aead_alg_maxauthsize(alg); + + err = -EINVAL; + if (ivsize < sizeof(u64)) + goto err_drop_alg; + + err = -ENAMETOOLONG; + 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.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.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_ctxsize = sizeof(struct aead_geniv_ctx); + + inst->alg.setkey = aead_geniv_setkey; + inst->alg.setauthsize = aead_geniv_setauthsize; + + inst->alg.ivsize = ivsize; + inst->alg.maxauthsize = maxauthsize; + +out: + return inst; + +err_drop_alg: + crypto_drop_aead(spawn); +err_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} +EXPORT_SYMBOL_GPL(aead_geniv_alloc); + +void aead_geniv_free(struct aead_instance *inst) +{ + crypto_drop_aead(aead_instance_ctx(inst)); + kfree(inst); +} +EXPORT_SYMBOL_GPL(aead_geniv_free); + +int aead_init_geniv(struct crypto_aead *aead) +{ + struct aead_geniv_ctx *ctx = crypto_aead_ctx(aead); + struct aead_instance *inst = aead_alg_instance(aead); + struct crypto_aead *child; + int err; + + spin_lock_init(&ctx->lock); + + err = crypto_get_default_rng(); + if (err) + goto out; + + err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt, + crypto_aead_ivsize(aead)); + crypto_put_default_rng(); + if (err) + goto out; + + ctx->sknull = crypto_get_default_null_skcipher(); + err = PTR_ERR(ctx->sknull); + if (IS_ERR(ctx->sknull)) + goto out; + + child = crypto_spawn_aead(aead_instance_ctx(inst)); + err = PTR_ERR(child); + if (IS_ERR(child)) + goto drop_null; + + ctx->child = child; + crypto_aead_set_reqsize(aead, crypto_aead_reqsize(child) + + sizeof(struct aead_request)); + + err = 0; + +out: + return err; + +drop_null: + crypto_put_default_null_skcipher(); + goto out; +} +EXPORT_SYMBOL_GPL(aead_init_geniv); + +void aead_exit_geniv(struct crypto_aead *tfm) +{ + struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm); + + crypto_free_aead(ctx->child); + crypto_put_default_null_skcipher(); +} +EXPORT_SYMBOL_GPL(aead_exit_geniv); + +int crypto_grab_aead(struct crypto_aead_spawn *spawn, const char *name, + u32 type, u32 mask) +{ + spawn->base.frontend = &crypto_aead_type; + return crypto_grab_spawn(&spawn->base, name, type, mask); +} +EXPORT_SYMBOL_GPL(crypto_grab_aead); + +struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask) +{ + return crypto_alloc_tfm(alg_name, &crypto_aead_type, type, mask); +} +EXPORT_SYMBOL_GPL(crypto_alloc_aead); + +static int aead_prepare_alg(struct aead_alg *alg) +{ + struct crypto_alg *base = &alg->base; + + if (max3(alg->maxauthsize, alg->ivsize, alg->chunksize) > + PAGE_SIZE / 8) + return -EINVAL; + + if (!alg->chunksize) + alg->chunksize = base->cra_blocksize; + + base->cra_type = &crypto_aead_type; + base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; + base->cra_flags |= CRYPTO_ALG_TYPE_AEAD; + + return 0; +} + +int crypto_register_aead(struct aead_alg *alg) +{ + struct crypto_alg *base = &alg->base; + int err; + + err = aead_prepare_alg(alg); + if (err) + return err; + + return crypto_register_alg(base); +} +EXPORT_SYMBOL_GPL(crypto_register_aead); + +void crypto_unregister_aead(struct aead_alg *alg) +{ + crypto_unregister_alg(&alg->base); +} +EXPORT_SYMBOL_GPL(crypto_unregister_aead); + +int crypto_register_aeads(struct aead_alg *algs, int count) +{ + int i, ret; + + for (i = 0; i < count; i++) { + ret = crypto_register_aead(&algs[i]); + if (ret) + goto err; + } + + return 0; + +err: + for (--i; i >= 0; --i) + crypto_unregister_aead(&algs[i]); + + return ret; +} +EXPORT_SYMBOL_GPL(crypto_register_aeads); + +void crypto_unregister_aeads(struct aead_alg *algs, int count) +{ + int i; + + for (i = count - 1; i >= 0; --i) + crypto_unregister_aead(&algs[i]); +} +EXPORT_SYMBOL_GPL(crypto_unregister_aeads); + +int aead_register_instance(struct crypto_template *tmpl, + struct aead_instance *inst) +{ + int err; + + err = aead_prepare_alg(&inst->alg); + if (err) + return err; + + return crypto_register_instance(tmpl, aead_crypto_instance(inst)); +} +EXPORT_SYMBOL_GPL(aead_register_instance); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Authenticated Encryption with Associated Data (AEAD)"); |