nfsd: Add Jeff Layton as co-maintainer

[mirror_ubuntu-artful-kernel.git] / crypto / aead.c

/*
 * AEAD: Authenticated Encryption with Associated Data
 *
 * This file provides API support for AEAD algorithms.
 *
 * 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/internal/geniv.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/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/cryptouser.h>
#include <net/netlink.h>

#include "internal.h"

struct compat_request_ctx {
        struct scatterlist src[2];
        struct scatterlist dst[2];
        struct scatterlist ivbuf[2];
        struct scatterlist *ivsg;
        struct aead_givcrypt_request subreq;
};

static int aead_null_givencrypt(struct aead_givcrypt_request *req);
static int aead_null_givdecrypt(struct aead_givcrypt_request *req);

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 = 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);

        tfm = tfm->child;

        if ((unsigned long)key & alignmask)
                return setkey_unaligned(tfm, key, keylen);

        return tfm->setkey(tfm, key, keylen);
}
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 (tfm->setauthsize) {
                err = tfm->setauthsize(tfm->child, authsize);
                if (err)
                        return err;
        }

        tfm->child->authsize = authsize;
        tfm->authsize = authsize;
        return 0;
}
EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);

struct aead_old_request {
        struct scatterlist srcbuf[2];
        struct scatterlist dstbuf[2];
        struct aead_request subreq;
};

unsigned int crypto_aead_reqsize(struct crypto_aead *tfm)
{
        return tfm->reqsize + sizeof(struct aead_old_request);
}
EXPORT_SYMBOL_GPL(crypto_aead_reqsize);

static int old_crypt(struct aead_request *req,
                     int (*crypt)(struct aead_request *req))
{
        struct aead_old_request *nreq = aead_request_ctx(req);
        struct crypto_aead *aead = crypto_aead_reqtfm(req);
        struct scatterlist *src, *dst;

        if (req->old)
                return crypt(req);

        src = scatterwalk_ffwd(nreq->srcbuf, req->src, req->assoclen);
        dst = req->src == req->dst ?
              src : scatterwalk_ffwd(nreq->dstbuf, req->dst, req->assoclen);

        aead_request_set_tfm(&nreq->subreq, aead);
        aead_request_set_callback(&nreq->subreq, aead_request_flags(req),
                                  req->base.complete, req->base.data);
        aead_request_set_crypt(&nreq->subreq, src, dst, req->cryptlen,
                               req->iv);
        aead_request_set_assoc(&nreq->subreq, req->src, req->assoclen);

        return crypt(&nreq->subreq);
}

static int old_encrypt(struct aead_request *req)
{
        struct crypto_aead *aead = crypto_aead_reqtfm(req);
        struct old_aead_alg *alg = crypto_old_aead_alg(aead);

        return old_crypt(req, alg->encrypt);
}

static int old_decrypt(struct aead_request *req)
{
        struct crypto_aead *aead = crypto_aead_reqtfm(req);
        struct old_aead_alg *alg = crypto_old_aead_alg(aead);

        return old_crypt(req, alg->decrypt);
}

static int no_givcrypt(struct aead_givcrypt_request *req)
{
        return -ENOSYS;
}

static int crypto_old_aead_init_tfm(struct crypto_tfm *tfm)
{
        struct old_aead_alg *alg = &tfm->__crt_alg->cra_aead;
        struct crypto_aead *crt = __crypto_aead_cast(tfm);

        if (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
                return -EINVAL;

        crt->setkey = alg->setkey;
        crt->setauthsize = alg->setauthsize;
        crt->encrypt = old_encrypt;
        crt->decrypt = old_decrypt;
        if (alg->ivsize) {
                crt->givencrypt = alg->givencrypt ?: no_givcrypt;
                crt->givdecrypt = alg->givdecrypt ?: no_givcrypt;
        } else {
                crt->givencrypt = aead_null_givencrypt;
                crt->givdecrypt = aead_null_givdecrypt;
        }
        crt->child = __crypto_aead_cast(tfm);
        crt->authsize = alg->maxauthsize;

        return 0;
}

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);

        if (crypto_old_aead_alg(aead)->encrypt)
                return crypto_old_aead_init_tfm(tfm);

        aead->setkey = alg->setkey;
        aead->setauthsize = alg->setauthsize;
        aead->encrypt = alg->encrypt;
        aead->decrypt = alg->decrypt;
        aead->child = __crypto_aead_cast(tfm);
        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_old_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
{
        struct crypto_report_aead raead;
        struct old_aead_alg *aead = &alg->cra_aead;

        strncpy(raead.type, "aead", sizeof(raead.type));
        strncpy(raead.geniv, aead->geniv ?: "<built-in>", 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_old_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
{
        return -ENOSYS;
}
#endif

static void crypto_old_aead_show(struct seq_file *m, struct crypto_alg *alg)
        __attribute__ ((unused));
static void crypto_old_aead_show(struct seq_file *m, struct crypto_alg *alg)
{
        struct old_aead_alg *aead = &alg->cra_aead;

        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        : %s\n", aead->geniv ?: "<built-in>");
}

const struct crypto_type crypto_aead_type = {
        .extsize = crypto_alg_extsize,
        .init_tfm = crypto_aead_init_tfm,
#ifdef CONFIG_PROC_FS
        .show = crypto_old_aead_show,
#endif
        .report = crypto_old_aead_report,
        .lookup = crypto_lookup_aead,
        .maskclear = ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV),
        .maskset = CRYPTO_ALG_TYPE_MASK,
        .type = CRYPTO_ALG_TYPE_AEAD,
        .tfmsize = offsetof(struct crypto_aead, base),
};
EXPORT_SYMBOL_GPL(crypto_aead_type);

#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)
        __attribute__ ((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 const struct crypto_type crypto_new_aead_type = {
        .extsize = crypto_alg_extsize,
        .init_tfm = crypto_aead_init_tfm,
#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_null_givencrypt(struct aead_givcrypt_request *req)
{
        return crypto_aead_encrypt(&req->areq);
}

static int aead_null_givdecrypt(struct aead_givcrypt_request *req)
{
        return crypto_aead_decrypt(&req->areq);
}

#ifdef CONFIG_NET
static int crypto_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
{
        struct crypto_report_aead raead;
        struct old_aead_alg *aead = &alg->cra_aead;

        strncpy(raead.type, "nivaead", sizeof(raead.type));
        strncpy(raead.geniv, aead->geniv, 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_nivaead_report(struct sk_buff *skb, struct crypto_alg *alg)
{
        return -ENOSYS;
}
#endif


static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
        __attribute__ ((unused));
static void crypto_nivaead_show(struct seq_file *m, struct crypto_alg *alg)
{
        struct old_aead_alg *aead = &alg->cra_aead;

        seq_printf(m, "type         : nivaead\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        : %s\n", aead->geniv);
}

const struct crypto_type crypto_nivaead_type = {
        .extsize = crypto_alg_extsize,
        .init_tfm = crypto_aead_init_tfm,
#ifdef CONFIG_PROC_FS
        .show = crypto_nivaead_show,
#endif
        .report = crypto_nivaead_report,
        .maskclear = ~(CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV),
        .maskset = CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV,
        .type = CRYPTO_ALG_TYPE_AEAD,
        .tfmsize = offsetof(struct crypto_aead, base),
};
EXPORT_SYMBOL_GPL(crypto_nivaead_type);

static int crypto_grab_nivaead(struct crypto_aead_spawn *spawn,
                               const char *name, u32 type, u32 mask)
{
        spawn->base.frontend = &crypto_nivaead_type;
        return crypto_grab_spawn(&spawn->base, name, type, mask);
}

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);
}

static void compat_encrypt_complete2(struct aead_request *req, int err)
{
        struct compat_request_ctx *rctx = aead_request_ctx(req);
        struct aead_givcrypt_request *subreq = &rctx->subreq;
        struct crypto_aead *geniv;

        if (err == -EINPROGRESS)
                return;

        if (err)
                goto out;

        geniv = crypto_aead_reqtfm(req);
        scatterwalk_map_and_copy(subreq->giv, rctx->ivsg, 0,
                                 crypto_aead_ivsize(geniv), 1);

out:
        kzfree(subreq->giv);
}

static void compat_encrypt_complete(struct crypto_async_request *base, int err)
{
        struct aead_request *req = base->data;

        compat_encrypt_complete2(req, err);
        aead_request_complete(req, err);
}

static int compat_encrypt(struct aead_request *req)
{
        struct crypto_aead *geniv = crypto_aead_reqtfm(req);
        struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
        struct compat_request_ctx *rctx = aead_request_ctx(req);
        struct aead_givcrypt_request *subreq = &rctx->subreq;
        unsigned int ivsize = crypto_aead_ivsize(geniv);
        struct scatterlist *src, *dst;
        crypto_completion_t compl;
        void *data;
        u8 *info;
        __be64 seq;
        int err;

        if (req->cryptlen < ivsize)
                return -EINVAL;

        compl = req->base.complete;
        data = req->base.data;

        rctx->ivsg = scatterwalk_ffwd(rctx->ivbuf, req->dst, req->assoclen);
        info = PageHighMem(sg_page(rctx->ivsg)) ? NULL : sg_virt(rctx->ivsg);

        if (!info) {
                info = kmalloc(ivsize, req->base.flags &
                                       CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL:
                                                                  GFP_ATOMIC);
                if (!info)
                        return -ENOMEM;

                compl = compat_encrypt_complete;
                data = req;
        }

        memcpy(&seq, req->iv + ivsize - sizeof(seq), sizeof(seq));

        src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen + ivsize);
        dst = req->src == req->dst ?
              src : scatterwalk_ffwd(rctx->dst, rctx->ivsg, ivsize);

        aead_givcrypt_set_tfm(subreq, ctx->child);
        aead_givcrypt_set_callback(subreq, req->base.flags,
                                   req->base.complete, req->base.data);
        aead_givcrypt_set_crypt(subreq, src, dst,
                                req->cryptlen - ivsize, req->iv);
        aead_givcrypt_set_assoc(subreq, req->src, req->assoclen);
        aead_givcrypt_set_giv(subreq, info, be64_to_cpu(seq));

        err = crypto_aead_givencrypt(subreq);
        if (unlikely(PageHighMem(sg_page(rctx->ivsg))))
                compat_encrypt_complete2(req, err);
        return err;
}

static int compat_decrypt(struct aead_request *req)
{
        struct crypto_aead *geniv = crypto_aead_reqtfm(req);
        struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
        struct compat_request_ctx *rctx = aead_request_ctx(req);
        struct aead_request *subreq = &rctx->subreq.areq;
        unsigned int ivsize = crypto_aead_ivsize(geniv);
        struct scatterlist *src, *dst;
        crypto_completion_t compl;
        void *data;

        if (req->cryptlen < ivsize)
                return -EINVAL;

        aead_request_set_tfm(subreq, ctx->child);

        compl = req->base.complete;
        data = req->base.data;

        src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen + ivsize);
        dst = req->src == req->dst ?
              src : scatterwalk_ffwd(rctx->dst, req->dst,
                                     req->assoclen + ivsize);

        aead_request_set_callback(subreq, req->base.flags, compl, data);
        aead_request_set_crypt(subreq, src, dst,
                               req->cryptlen - ivsize, req->iv);
        aead_request_set_assoc(subreq, req->src, req->assoclen);

        scatterwalk_map_and_copy(req->iv, req->src, req->assoclen, ivsize, 0);

        return crypto_aead_decrypt(subreq);
}

static int compat_encrypt_first(struct aead_request *req)
{
        struct crypto_aead *geniv = crypto_aead_reqtfm(req);
        struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
        int err = 0;

        spin_lock_bh(&ctx->lock);
        if (geniv->encrypt != compat_encrypt_first)
                goto unlock;

        geniv->encrypt = compat_encrypt;

unlock:
        spin_unlock_bh(&ctx->lock);

        if (err)
                return err;

        return compat_encrypt(req);
}

static int aead_geniv_init_compat(struct crypto_tfm *tfm)
{
        struct crypto_aead *geniv = __crypto_aead_cast(tfm);
        struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);
        int err;

        spin_lock_init(&ctx->lock);

        crypto_aead_set_reqsize(geniv, sizeof(struct compat_request_ctx));

        err = aead_geniv_init(tfm);

        ctx->child = geniv->child;
        geniv->child = geniv;

        return err;
}

static void aead_geniv_exit_compat(struct crypto_tfm *tfm)
{
        struct crypto_aead *geniv = __crypto_aead_cast(tfm);
        struct aead_geniv_ctx *ctx = crypto_aead_ctx(geniv);

        crypto_free_aead(ctx->child);
}

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 | CRYPTO_ALG_GENIV)) &
            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 = (algt->mask & CRYPTO_ALG_GENIV) ?
              crypto_grab_nivaead(spawn, name, type, mask) :
              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;

        /*
         * This is only true if we're constructing an algorithm with its
         * default IV generator.  For the default generator we elide the
         * template name and double-check the IV generator.
         */
        if (algt->mask & CRYPTO_ALG_GENIV) {
                if (!alg->base.cra_aead.encrypt)
                        goto err_drop_alg;
                if (strcmp(tmpl->name, alg->base.cra_aead.geniv))
                        goto err_drop_alg;

                memcpy(inst->alg.base.cra_name, alg->base.cra_name,
                       CRYPTO_MAX_ALG_NAME);
                memcpy(inst->alg.base.cra_driver_name,
                       alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME);

                inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_AEAD |
                                           CRYPTO_ALG_GENIV;
                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_type = &crypto_aead_type;

                inst->alg.base.cra_aead.ivsize = ivsize;
                inst->alg.base.cra_aead.maxauthsize = maxauthsize;

                inst->alg.base.cra_aead.setkey = alg->base.cra_aead.setkey;
                inst->alg.base.cra_aead.setauthsize =
                        alg->base.cra_aead.setauthsize;
                inst->alg.base.cra_aead.encrypt = alg->base.cra_aead.encrypt;
                inst->alg.base.cra_aead.decrypt = alg->base.cra_aead.decrypt;

                goto out;
        }

        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;

        inst->alg.encrypt = compat_encrypt_first;
        inst->alg.decrypt = compat_decrypt;

        inst->alg.base.cra_init = aead_geniv_init_compat;
        inst->alg.base.cra_exit = aead_geniv_exit_compat;

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_geniv_init(struct crypto_tfm *tfm)
{
        struct crypto_instance *inst = (void *)tfm->__crt_alg;
        struct crypto_aead *child;
        struct crypto_aead *aead;

        aead = __crypto_aead_cast(tfm);

        child = crypto_spawn_aead(crypto_instance_ctx(inst));
        if (IS_ERR(child))
                return PTR_ERR(child);

        aead->child = child;
        aead->reqsize += crypto_aead_reqsize(child);

        return 0;
}
EXPORT_SYMBOL_GPL(aead_geniv_init);

void aead_geniv_exit(struct crypto_tfm *tfm)
{
        crypto_free_aead(__crypto_aead_cast(tfm)->child);
}
EXPORT_SYMBOL_GPL(aead_geniv_exit);

static int crypto_nivaead_default(struct crypto_alg *alg, u32 type, u32 mask)
{
        struct rtattr *tb[3];
        struct {
                struct rtattr attr;
                struct crypto_attr_type data;
        } ptype;
        struct {
                struct rtattr attr;
                struct crypto_attr_alg data;
        } palg;
        struct crypto_template *tmpl;
        struct crypto_instance *inst;
        struct crypto_alg *larval;
        const char *geniv;
        int err;

        larval = crypto_larval_lookup(alg->cra_driver_name,
                                      CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_GENIV,
                                      CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_GENIV);
        err = PTR_ERR(larval);
        if (IS_ERR(larval))
                goto out;

        err = -EAGAIN;
        if (!crypto_is_larval(larval))
                goto drop_larval;

        ptype.attr.rta_len = sizeof(ptype);
        ptype.attr.rta_type = CRYPTOA_TYPE;
        ptype.data.type = type | CRYPTO_ALG_GENIV;
        /* GENIV tells the template that we're making a default geniv. */
        ptype.data.mask = mask | CRYPTO_ALG_GENIV;
        tb[0] = &ptype.attr;

        palg.attr.rta_len = sizeof(palg);
        palg.attr.rta_type = CRYPTOA_ALG;
        /* Must use the exact name to locate ourselves. */
        memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME);
        tb[1] = &palg.attr;

        tb[2] = NULL;

        geniv = alg->cra_aead.geniv;

        tmpl = crypto_lookup_template(geniv);
        err = -ENOENT;
        if (!tmpl)
                goto kill_larval;

        if (tmpl->create) {
                err = tmpl->create(tmpl, tb);
                if (err)
                        goto put_tmpl;
                goto ok;
        }

        inst = tmpl->alloc(tb);
        err = PTR_ERR(inst);
        if (IS_ERR(inst))
                goto put_tmpl;

        err = crypto_register_instance(tmpl, inst);
        if (err) {
                tmpl->free(inst);
                goto put_tmpl;
        }

ok:
        /* Redo the lookup to use the instance we just registered. */
        err = -EAGAIN;

put_tmpl:
        crypto_tmpl_put(tmpl);
kill_larval:
        crypto_larval_kill(larval);
drop_larval:
        crypto_mod_put(larval);
out:
        crypto_mod_put(alg);
        return err;
}

struct crypto_alg *crypto_lookup_aead(const char *name, u32 type, u32 mask)
{
        struct crypto_alg *alg;

        alg = crypto_alg_mod_lookup(name, type, mask);
        if (IS_ERR(alg))
                return alg;

        if (alg->cra_type == &crypto_aead_type)
                return alg;

        if (!alg->cra_aead.ivsize)
                return alg;

        crypto_mod_put(alg);
        alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED,
                                    mask & ~CRYPTO_ALG_TESTED);
        if (IS_ERR(alg))
                return alg;

        if (alg->cra_type == &crypto_aead_type) {
                if (~alg->cra_flags & (type ^ ~mask) & CRYPTO_ALG_TESTED) {
                        crypto_mod_put(alg);
                        alg = ERR_PTR(-ENOENT);
                }
                return alg;
        }

        BUG_ON(!alg->cra_aead.ivsize);

        return ERR_PTR(crypto_nivaead_default(alg, type, mask));
}
EXPORT_SYMBOL_GPL(crypto_lookup_aead);

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 (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
                return -EINVAL;

        base->cra_type = &crypto_new_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)");