/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2005-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/linker.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/kthread.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <sys/smp.h>
#include <sys/vnode.h>

#include <vm/uma.h>

#include <geom/geom.h>
#include <geom/geom_dbg.h>
#include <geom/eli/g_eli.h>
#include <geom/eli/pkcs5v2.h>

/*
 * The data layout description when integrity verification is configured.
 *
 * One of the most important assumption here is that authenticated data and its
 * HMAC has to be stored in the same place (namely in the same sector) to make
 * it work reliable.
 * The problem is that file systems work only with sectors that are multiple of
 * 512 bytes and a power of two number.
 * My idea to implement it is as follows.
 * Let's store HMAC in sector. This is a must. This leaves us 480 bytes for
 * data. We can't use that directly (ie. we can't create provider with 480 bytes
 * sector size). We need another sector from where we take only 32 bytes of data
 * and we store HMAC of this data as well. This takes two sectors from the
 * original provider at the input and leaves us one sector of authenticated data
 * at the output. Not very efficient, but you got the idea.
 * Now, let's assume, we want to create provider with 4096 bytes sector.
 * To output 4096 bytes of authenticated data we need 8x480 plus 1x256, so we
 * need nine 512-bytes sectors at the input to get one 4096-bytes sector at the
 * output. That's better. With 4096 bytes sector we can use 89% of size of the
 * original provider. I find it as an acceptable cost.
 * The reliability comes from the fact, that every HMAC stored inside the sector
 * is calculated only for the data in the same sector, so its impossible to
 * write new data and leave old HMAC or vice versa.
 *
 * And here is the picture:
 *
 * da0: +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+-----+
 *      |32b |480b| |32b |480b| |32b |480b| |32b |480b| |32b |480b| |32b |480b| |32b |480b| |32b |480b| |32b |256b |
 *      |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data| |HMAC|Data |
 *      +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+----+ +----+-----+
 *      |512 bytes| |512 bytes| |512 bytes| |512 bytes| |512 bytes| |512 bytes| |512 bytes| |512 bytes| |288 bytes |
 *      +---------+ +---------+ +---------+ +---------+ +---------+ +---------+ +---------+ +---------+ |224 unused|
 *                                                                                                      +----------+
 * da0.eli: +----+----+----+----+----+----+----+----+----+
 *          |480b|480b|480b|480b|480b|480b|480b|480b|256b|
 *          +----+----+----+----+----+----+----+----+----+
 *          |                 4096 bytes                 |
 *          +--------------------------------------------+
 *
 * PS. You can use any sector size with geli(8). My example is using 4kB,
 *     because it's most efficient. For 8kB sectors you need 2 extra sectors,
 *     so the cost is the same as for 4kB sectors.
 */

/*
 * Code paths:
 * BIO_READ:
 *      g_eli_start -> g_eli_auth_read -> g_io_request -> g_eli_read_done -> g_eli_auth_run -> g_eli_auth_read_done -> g_io_deliver
 * BIO_WRITE:
 *      g_eli_start -> g_eli_auth_run -> g_eli_auth_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
 */

/*
 * Here we generate key for HMAC. Every sector has its own HMAC key, so it is
 * not possible to copy sectors.
 * We cannot depend on fact, that every sector has its own IV, because different
 * IV doesn't change HMAC, when we use encrypt-then-authenticate method.
 */
static void
g_eli_auth_keygen(struct g_eli_softc *sc, off_t offset, u_char *key)
{
        SHA256_CTX ctx;

        /* Copy precalculated SHA256 context. */
        bcopy(&sc->sc_akeyctx, &ctx, sizeof(ctx));
        SHA256_Update(&ctx, (uint8_t *)&offset, sizeof(offset));
        SHA256_Final(key, &ctx);
}

/*
 * The function is called after we read and decrypt data.
 *
 * g_eli_start -> g_eli_auth_read -> g_io_request -> g_eli_read_done -> g_eli_auth_run -> G_ELI_AUTH_READ_DONE -> g_io_deliver
 */
static int
g_eli_auth_read_done(struct cryptop *crp)
{
        struct g_eli_softc *sc;
        struct bio *bp;

        if (crp->crp_etype == EAGAIN) {
                if (g_eli_crypto_rerun(crp) == 0)
                        return (0);
        }
        bp = (struct bio *)crp->crp_opaque;
        bp->bio_inbed++;
        sc = bp->bio_to->geom->softc;
        if (crp->crp_etype == 0) {
                bp->bio_completed += crp->crp_payload_length;
                G_ELI_DEBUG(3, "Crypto READ request done (%d/%d) (add=%d completed=%jd).",
                    bp->bio_inbed, bp->bio_children, crp->crp_payload_length, (intmax_t)bp->bio_completed);
        } else {
                u_int nsec, decr_secsize, encr_secsize, rel_sec;
                int *errorp;

                /* Sectorsize of decrypted provider eg. 4096. */
                decr_secsize = bp->bio_to->sectorsize;
                /* The real sectorsize of encrypted provider, eg. 512. */
                encr_secsize =
                    LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize;
                /* Number of sectors from decrypted provider, eg. 2. */
                nsec = bp->bio_length / decr_secsize;
                /* Number of sectors from encrypted provider, eg. 18. */
                nsec = (nsec * sc->sc_bytes_per_sector) / encr_secsize;
                /* Which relative sector this request decrypted. */
                rel_sec = ((crp->crp_buf.cb_buf + crp->crp_payload_start) -
                    (char *)bp->bio_driver2) / encr_secsize;

                errorp = (int *)((char *)bp->bio_driver2 + encr_secsize * nsec +
                    sizeof(int) * rel_sec);
                *errorp = crp->crp_etype;
                G_ELI_DEBUG(1,
                    "Crypto READ request failed (%d/%d) error=%d.",
                    bp->bio_inbed, bp->bio_children, crp->crp_etype);
                if (bp->bio_error == 0 || bp->bio_error == EINTEGRITY)
                        bp->bio_error = crp->crp_etype == EBADMSG ?
                            EINTEGRITY : crp->crp_etype;
        }
        if (crp->crp_cipher_key != NULL)
                g_eli_key_drop(sc, __DECONST(void *, crp->crp_cipher_key));
        crypto_freereq(crp);
        /*
         * Do we have all sectors already?
         */
        if (bp->bio_inbed < bp->bio_children)
                return (0);

        if (bp->bio_error == 0) {
                u_int i, lsec, nsec, data_secsize, decr_secsize, encr_secsize;
                u_char *srcdata, *dstdata;

                /* Sectorsize of decrypted provider eg. 4096. */
                decr_secsize = bp->bio_to->sectorsize;
                /* The real sectorsize of encrypted provider, eg. 512. */
                encr_secsize = LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize;
                /* Number of data bytes in one encrypted sector, eg. 480. */
                data_secsize = sc->sc_data_per_sector;
                /* Number of sectors from decrypted provider, eg. 2. */
                nsec = bp->bio_length / decr_secsize;
                /* Number of sectors from encrypted provider, eg. 18. */
                nsec = (nsec * sc->sc_bytes_per_sector) / encr_secsize;
                /* Last sector number in every big sector, eg. 9. */
                lsec = sc->sc_bytes_per_sector / encr_secsize;

                srcdata = bp->bio_driver2;
                dstdata = bp->bio_data;

                for (i = 1; i <= nsec; i++) {
                        data_secsize = sc->sc_data_per_sector;
                        if ((i % lsec) == 0)
                                data_secsize = decr_secsize % data_secsize;
                        bcopy(srcdata + sc->sc_alen, dstdata, data_secsize);
                        srcdata += encr_secsize;
                        dstdata += data_secsize;
                }
        } else if (bp->bio_error == EINTEGRITY) {
                u_int i, lsec, nsec, data_secsize, decr_secsize, encr_secsize;
                int *errorp;
                off_t coroff, corsize, dstoff;

                /* Sectorsize of decrypted provider eg. 4096. */
                decr_secsize = bp->bio_to->sectorsize;
                /* The real sectorsize of encrypted provider, eg. 512. */
                encr_secsize = LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize;
                /* Number of data bytes in one encrypted sector, eg. 480. */
                data_secsize = sc->sc_data_per_sector;
                /* Number of sectors from decrypted provider, eg. 2. */
                nsec = bp->bio_length / decr_secsize;
                /* Number of sectors from encrypted provider, eg. 18. */
                nsec = (nsec * sc->sc_bytes_per_sector) / encr_secsize;
                /* Last sector number in every big sector, eg. 9. */
                lsec = sc->sc_bytes_per_sector / encr_secsize;

                errorp = (int *)((char *)bp->bio_driver2 + encr_secsize * nsec);
                coroff = -1;
                corsize = 0;
                dstoff = bp->bio_offset;

                for (i = 1; i <= nsec; i++) {
                        data_secsize = sc->sc_data_per_sector;
                        if ((i % lsec) == 0)
                                data_secsize = decr_secsize % data_secsize;
                        if (errorp[i - 1] == EBADMSG) {
                                /*
                                 * Corruption detected, remember the offset if
                                 * this is the first corrupted sector and
                                 * increase size.
                                 */
                                if (coroff == -1)
                                        coroff = dstoff;
                                corsize += data_secsize;
                        } else {
                                /*
                                 * No corruption, good.
                                 * Report previous corruption if there was one.
                                 */
                                if (coroff != -1) {
                                        G_ELI_DEBUG(0, "%s: Failed to authenticate %jd "
                                            "bytes of data at offset %jd.",
                                            sc->sc_name, (intmax_t)corsize,
                                            (intmax_t)coroff);
                                        coroff = -1;
                                        corsize = 0;
                                }
                        }
                        dstoff += data_secsize;
                }
                /* Report previous corruption if there was one. */
                if (coroff != -1) {
                        G_ELI_DEBUG(0, "%s: Failed to authenticate %jd "
                            "bytes of data at offset %jd.",
                            sc->sc_name, (intmax_t)corsize, (intmax_t)coroff);
                }
        }
        g_eli_free_data(bp);
        if (bp->bio_error != 0) {
                if (bp->bio_error != EINTEGRITY) {
                        G_ELI_LOGREQ(0, bp,
                            "Crypto READ request failed (error=%d).",
                            bp->bio_error);
                }
                bp->bio_completed = 0;
        }
        /*
         * Read is finished, send it up.
         */
        g_io_deliver(bp, bp->bio_error);
        atomic_subtract_int(&sc->sc_inflight, 1);
        return (0);
}

/*
 * The function is called after data encryption.
 *
 * g_eli_start -> g_eli_auth_run -> G_ELI_AUTH_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver
 */
static int
g_eli_auth_write_done(struct cryptop *crp)
{
        struct g_eli_softc *sc;
        struct g_consumer *cp;
        struct bio *bp, *cbp, *cbp2;
        u_int nsec;

        if (crp->crp_etype == EAGAIN) {
                if (g_eli_crypto_rerun(crp) == 0)
                        return (0);
        }
        bp = (struct bio *)crp->crp_opaque;
        bp->bio_inbed++;
        if (crp->crp_etype == 0) {
                G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).",
                    bp->bio_inbed, bp->bio_children);
        } else {
                G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.",
                    bp->bio_inbed, bp->bio_children, crp->crp_etype);
                if (bp->bio_error == 0)
                        bp->bio_error = crp->crp_etype;
        }
        sc = bp->bio_to->geom->softc;
        if (crp->crp_cipher_key != NULL)
                g_eli_key_drop(sc, __DECONST(void *, crp->crp_cipher_key));
        crypto_freereq(crp);
        /*
         * All sectors are already encrypted?
         */
        if (bp->bio_inbed < bp->bio_children)
                return (0);
        if (bp->bio_error != 0) {
                G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).",
                    bp->bio_error);
                g_eli_free_data(bp);
                cbp = bp->bio_driver1;
                bp->bio_driver1 = NULL;
                g_destroy_bio(cbp);
                g_io_deliver(bp, bp->bio_error);
                atomic_subtract_int(&sc->sc_inflight, 1);
                return (0);
        }
        cp = LIST_FIRST(&sc->sc_geom->consumer);
        cbp = bp->bio_driver1;
        bp->bio_driver1 = NULL;
        cbp->bio_to = cp->provider;
        cbp->bio_done = g_eli_write_done;

        /* Number of sectors from decrypted provider, eg. 1. */
        nsec = bp->bio_length / bp->bio_to->sectorsize;
        /* Number of sectors from encrypted provider, eg. 9. */
        nsec = (nsec * sc->sc_bytes_per_sector) / cp->provider->sectorsize;

        cbp->bio_length = cp->provider->sectorsize * nsec;
        cbp->bio_offset = (bp->bio_offset / bp->bio_to->sectorsize) * sc->sc_bytes_per_sector;
        cbp->bio_data = bp->bio_driver2;

        /*
         * We write more than what is requested, so we have to be ready to write
         * more than maxphys.
         */
        cbp2 = NULL;
        if (cbp->bio_length > maxphys) {
                cbp2 = g_duplicate_bio(bp);
                cbp2->bio_length = cbp->bio_length - maxphys;
                cbp2->bio_data = cbp->bio_data + maxphys;
                cbp2->bio_offset = cbp->bio_offset + maxphys;
                cbp2->bio_to = cp->provider;
                cbp2->bio_done = g_eli_write_done;
                cbp->bio_length = maxphys;
        }
        /*
         * Send encrypted data to the provider.
         */
        G_ELI_LOGREQ(2, cbp, "Sending request.");
        bp->bio_inbed = 0;
        bp->bio_children = (cbp2 != NULL ? 2 : 1);
        g_io_request(cbp, cp);
        if (cbp2 != NULL) {
                G_ELI_LOGREQ(2, cbp2, "Sending request.");
                g_io_request(cbp2, cp);
        }
        return (0);
}

void
g_eli_auth_read(struct g_eli_softc *sc, struct bio *bp)
{
        struct g_consumer *cp;
        struct bio *cbp, *cbp2;
        size_t size;
        off_t nsec;

        G_ELI_SETWORKER(bp->bio_pflags, 0);

        cp = LIST_FIRST(&sc->sc_geom->consumer);
        cbp = bp->bio_driver1;
        bp->bio_driver1 = NULL;
        cbp->bio_to = cp->provider;
        cbp->bio_done = g_eli_read_done;

        /* Number of sectors from decrypted provider, eg. 1. */
        nsec = bp->bio_length / bp->bio_to->sectorsize;
        /* Number of sectors from encrypted provider, eg. 9. */
        nsec = (nsec * sc->sc_bytes_per_sector) / cp->provider->sectorsize;

        cbp->bio_length = cp->provider->sectorsize * nsec;
        size = cbp->bio_length;
        size += sizeof(int) * nsec;
        size += G_ELI_AUTH_SECKEYLEN * nsec;
        cbp->bio_offset = (bp->bio_offset / bp->bio_to->sectorsize) * sc->sc_bytes_per_sector;
        if (!g_eli_alloc_data(bp, size)) {
                G_ELI_LOGREQ(0, bp, "Crypto auth read request failed (ENOMEM)");
                g_destroy_bio(cbp);
                bp->bio_error = ENOMEM;
                g_io_deliver(bp, bp->bio_error);
                atomic_subtract_int(&sc->sc_inflight, 1);
                return;
        }
        cbp->bio_data = bp->bio_driver2;

        /* Clear the error array. */
        memset((char *)bp->bio_driver2 + cbp->bio_length, 0,
            sizeof(int) * nsec);

        /*
         * We read more than what is requested, so we have to be ready to read
         * more than maxphys.
         */
        cbp2 = NULL;
        if (cbp->bio_length > maxphys) {
                cbp2 = g_duplicate_bio(bp);
                cbp2->bio_length = cbp->bio_length - maxphys;
                cbp2->bio_data = cbp->bio_data + maxphys;
                cbp2->bio_offset = cbp->bio_offset + maxphys;
                cbp2->bio_to = cp->provider;
                cbp2->bio_done = g_eli_read_done;
                cbp->bio_length = maxphys;
        }
        /*
         * Read encrypted data from provider.
         */
        G_ELI_LOGREQ(2, cbp, "Sending request.");
        g_io_request(cbp, cp);
        if (cbp2 != NULL) {
                G_ELI_LOGREQ(2, cbp2, "Sending request.");
                g_io_request(cbp2, cp);
        }
}

/*
 * This is the main function responsible for cryptography (ie. communication
 * with crypto(9) subsystem).
 *
 * BIO_READ:
 *      g_eli_start -> g_eli_auth_read -> g_io_request -> g_eli_read_done -> G_ELI_AUTH_RUN -> g_eli_auth_read_done -> g_io_deliver
 * BIO_WRITE:
 *      g_eli_start -> G_ELI_AUTH_RUN -> g_eli_auth_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
 */
void
g_eli_auth_run(struct g_eli_worker *wr, struct bio *bp)
{
        struct g_eli_softc *sc;
        struct cryptopq crpq;
        struct cryptop *crp;
        u_int i, lsec, nsec, data_secsize, decr_secsize, encr_secsize;
        off_t dstoff;
        u_char *p, *data, *authkey, *plaindata;
        int error __diagused;
        bool batch;

        G_ELI_LOGREQ(3, bp, "%s", __func__);

        G_ELI_SETWORKER(bp->bio_pflags, wr->w_number);
        sc = wr->w_softc;
        /* Sectorsize of decrypted provider eg. 4096. */
        decr_secsize = bp->bio_to->sectorsize;
        /* The real sectorsize of encrypted provider, eg. 512. */
        encr_secsize = LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize;
        /* Number of data bytes in one encrypted sector, eg. 480. */
        data_secsize = sc->sc_data_per_sector;
        /* Number of sectors from decrypted provider, eg. 2. */
        nsec = bp->bio_length / decr_secsize;
        /* Number of sectors from encrypted provider, eg. 18. */
        nsec = (nsec * sc->sc_bytes_per_sector) / encr_secsize;
        /* Last sector number in every big sector, eg. 9. */
        lsec = sc->sc_bytes_per_sector / encr_secsize;
        /* Destination offset, used for IV generation. */
        dstoff = (bp->bio_offset / bp->bio_to->sectorsize) * sc->sc_bytes_per_sector;

        plaindata = bp->bio_data;
        if (bp->bio_cmd == BIO_READ) {
                data = bp->bio_driver2;
                p = data + encr_secsize * nsec;
                p += sizeof(int) * nsec;
        } else {
                size_t size;

                size = encr_secsize * nsec;
                size += G_ELI_AUTH_SECKEYLEN * nsec;
                size += sizeof(uintptr_t);      /* Space for alignment. */
                if (!g_eli_alloc_data(bp, size)) {
                        G_ELI_LOGREQ(0, bp, "Crypto request failed (ENOMEM)");
                        if (bp->bio_driver1 != NULL) {
                                g_destroy_bio(bp->bio_driver1);
                                bp->bio_driver1 = NULL;
                        }
                        bp->bio_error = ENOMEM;
                        g_io_deliver(bp, bp->bio_error);
                        if (sc != NULL)
                                atomic_subtract_int(&sc->sc_inflight, 1);
                        return;
                }
                data = bp->bio_driver2;
                p = data + encr_secsize * nsec;
        }
        bp->bio_inbed = 0;
        bp->bio_children = nsec;

#if defined(__mips_n64) || defined(__mips_o64)
        p = (char *)roundup((uintptr_t)p, sizeof(uintptr_t));
#endif

        TAILQ_INIT(&crpq);
        batch = atomic_load_int(&g_eli_batch) != 0;

        for (i = 1; i <= nsec; i++, dstoff += encr_secsize) {
                crp = crypto_getreq(wr->w_sid, M_WAITOK);
                authkey = (u_char *)p;          p += G_ELI_AUTH_SECKEYLEN;

                data_secsize = sc->sc_data_per_sector;
                if ((i % lsec) == 0) {
                        data_secsize = decr_secsize % data_secsize;
                        /*
                         * Last encrypted sector of each decrypted sector is
                         * only partially filled.
                         */
                        if (bp->bio_cmd == BIO_WRITE)
                                memset(data + sc->sc_alen + data_secsize, 0,
                                    encr_secsize - sc->sc_alen - data_secsize);
                } else if (data_secsize + sc->sc_alen != encr_secsize) {
                        /*
                         * If the HMAC size is not a multiple of 128 bits, the
                         * per-sector data size is rounded down to ensure that
                         * encryption can be performed without requiring any
                         * padding.  In this case, each sector contains unused
                         * bytes.
                         */
                        if (bp->bio_cmd == BIO_WRITE)
                                memset(data + sc->sc_alen + data_secsize, 0,
                                    encr_secsize - sc->sc_alen - data_secsize);
                }

                if (bp->bio_cmd == BIO_WRITE) {
                        bcopy(plaindata, data + sc->sc_alen, data_secsize);
                        plaindata += data_secsize;
                }

                crypto_use_buf(crp, data, sc->sc_alen + data_secsize);
                crp->crp_opaque = (void *)bp;
                data += encr_secsize;
                crp->crp_flags = CRYPTO_F_CBIFSYNC;
                if (bp->bio_cmd == BIO_WRITE) {
                        crp->crp_callback = g_eli_auth_write_done;
                        crp->crp_op = CRYPTO_OP_ENCRYPT |
                            CRYPTO_OP_COMPUTE_DIGEST;
                } else {
                        crp->crp_callback = g_eli_auth_read_done;
                        crp->crp_op = CRYPTO_OP_DECRYPT |
                            CRYPTO_OP_VERIFY_DIGEST;
                }

                crp->crp_digest_start = 0;
                crp->crp_payload_start = sc->sc_alen;
                crp->crp_payload_length = data_secsize;
                if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) == 0) {
                        crp->crp_cipher_key = g_eli_key_hold(sc, dstoff,
                            encr_secsize);
                }
                if (g_eli_ivlen(sc->sc_ealgo) != 0) {
                        crp->crp_flags |= CRYPTO_F_IV_SEPARATE;
                        g_eli_crypto_ivgen(sc, dstoff, crp->crp_iv,
                            sizeof(crp->crp_iv));
                }

                g_eli_auth_keygen(sc, dstoff, authkey);
                crp->crp_auth_key = authkey;

                if (batch) {
                        TAILQ_INSERT_TAIL(&crpq, crp, crp_next);
                } else {
                        error = crypto_dispatch(crp);
                        KASSERT(error == 0,
                            ("crypto_dispatch() failed (error=%d)", error));
                }
        }

        if (batch)
                crypto_dispatch_batch(&crpq, 0);
}