/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2006-2008 Marcel Moolenaar
 * 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 AUTHOR ``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 AUTHOR 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/apm.h>
#include <sys/bio.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/kobj.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <geom/geom.h>
#include <geom/geom_int.h>
#include <geom/part/g_part.h>

#include "g_part_if.h"

FEATURE(geom_part_apm, "GEOM partitioning class for Apple-style partitions");

struct g_part_apm_table {
        struct g_part_table     base;
        struct apm_ddr          ddr;
        struct apm_ent          self;
        int                     tivo_series1;
};

struct g_part_apm_entry {
        struct g_part_entry     base;
        struct apm_ent          ent;
};

static int g_part_apm_add(struct g_part_table *, struct g_part_entry *,
    struct g_part_parms *);
static int g_part_apm_create(struct g_part_table *, struct g_part_parms *);
static int g_part_apm_destroy(struct g_part_table *, struct g_part_parms *);
static void g_part_apm_dumpconf(struct g_part_table *, struct g_part_entry *,
    struct sbuf *, const char *);
static int g_part_apm_dumpto(struct g_part_table *, struct g_part_entry *);
static int g_part_apm_modify(struct g_part_table *, struct g_part_entry *,
    struct g_part_parms *);
static const char *g_part_apm_name(struct g_part_table *, struct g_part_entry *,
    char *, size_t);
static int g_part_apm_probe(struct g_part_table *, struct g_consumer *);
static int g_part_apm_read(struct g_part_table *, struct g_consumer *);
static const char *g_part_apm_type(struct g_part_table *, struct g_part_entry *,
    char *, size_t);
static int g_part_apm_write(struct g_part_table *, struct g_consumer *);
static int g_part_apm_resize(struct g_part_table *, struct g_part_entry *,
    struct g_part_parms *);

static kobj_method_t g_part_apm_methods[] = {
        KOBJMETHOD(g_part_add,          g_part_apm_add),
        KOBJMETHOD(g_part_create,       g_part_apm_create),
        KOBJMETHOD(g_part_destroy,      g_part_apm_destroy),
        KOBJMETHOD(g_part_dumpconf,     g_part_apm_dumpconf),
        KOBJMETHOD(g_part_dumpto,       g_part_apm_dumpto),
        KOBJMETHOD(g_part_modify,       g_part_apm_modify),
        KOBJMETHOD(g_part_resize,       g_part_apm_resize),
        KOBJMETHOD(g_part_name,         g_part_apm_name),
        KOBJMETHOD(g_part_probe,        g_part_apm_probe),
        KOBJMETHOD(g_part_read,         g_part_apm_read),
        KOBJMETHOD(g_part_type,         g_part_apm_type),
        KOBJMETHOD(g_part_write,        g_part_apm_write),
        { 0, 0 }
};

static struct g_part_scheme g_part_apm_scheme = {
        "APM",
        g_part_apm_methods,
        sizeof(struct g_part_apm_table),
        .gps_entrysz = sizeof(struct g_part_apm_entry),
        .gps_minent = 16,
        .gps_defent = 16,
        .gps_maxent = 4096,
};
G_PART_SCHEME_DECLARE(g_part_apm);
MODULE_VERSION(geom_part_apm, 0);

static void
swab(char *buf, size_t bufsz)
{
        int i;
        char ch;

        for (i = 0; i < bufsz; i += 2) {
                ch = buf[i];
                buf[i] = buf[i + 1];
                buf[i + 1] = ch;
        }
}

static int
apm_parse_type(const char *type, char *buf, size_t bufsz)
{
        const char *alias;

        if (type[0] == '!') {
                type++;
                if (strlen(type) > bufsz)
                        return (EINVAL);
                if (!strcmp(type, APM_ENT_TYPE_SELF) ||
                    !strcmp(type, APM_ENT_TYPE_UNUSED))
                        return (EINVAL);
                strncpy(buf, type, bufsz);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_APPLE_BOOT);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_APPLE_BOOT);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_APPLE_HFS);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_APPLE_HFS);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_APPLE_UFS);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_APPLE_UFS);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_NANDFS);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD_NANDFS);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_SWAP);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD_SWAP);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_UFS);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD_UFS);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_VINUM);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD_VINUM);
                return (0);
        }
        alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_ZFS);
        if (!strcasecmp(type, alias)) {
                strcpy(buf, APM_ENT_TYPE_FREEBSD_ZFS);
                return (0);
        }
        return (EINVAL);
}

static int
apm_read_ent(struct g_consumer *cp, uint32_t blk, struct apm_ent *ent,
    int tivo_series1)
{
        struct g_provider *pp;
        char *buf;
        int error;

        pp = cp->provider;
        buf = g_read_data(cp, pp->sectorsize * blk, pp->sectorsize, &error);
        if (buf == NULL)
                return (error);
        if (tivo_series1)
                swab(buf, pp->sectorsize);
        ent->ent_sig = be16dec(buf);
        ent->ent_pmblkcnt = be32dec(buf + 4);
        ent->ent_start = be32dec(buf + 8);
        ent->ent_size = be32dec(buf + 12);
        bcopy(buf + 16, ent->ent_name, sizeof(ent->ent_name));
        bcopy(buf + 48, ent->ent_type, sizeof(ent->ent_type));
        g_free(buf);
        return (0);
}

static int
g_part_apm_add(struct g_part_table *basetable, struct g_part_entry *baseentry,
    struct g_part_parms *gpp)
{
        struct g_part_apm_entry *entry;
        struct g_part_apm_table *table;
        int error;

        entry = (struct g_part_apm_entry *)baseentry;
        table = (struct g_part_apm_table *)basetable;
        entry->ent.ent_sig = APM_ENT_SIG;
        entry->ent.ent_pmblkcnt = table->self.ent_pmblkcnt;
        entry->ent.ent_start = gpp->gpp_start;
        entry->ent.ent_size = gpp->gpp_size;
        if (baseentry->gpe_deleted) {
                bzero(entry->ent.ent_type, sizeof(entry->ent.ent_type));
                bzero(entry->ent.ent_name, sizeof(entry->ent.ent_name));
        }
        error = apm_parse_type(gpp->gpp_type, entry->ent.ent_type,
            sizeof(entry->ent.ent_type));
        if (error)
                return (error);
        if (gpp->gpp_parms & G_PART_PARM_LABEL) {
                if (strlen(gpp->gpp_label) > sizeof(entry->ent.ent_name))
                        return (EINVAL);
                strncpy(entry->ent.ent_name, gpp->gpp_label,
                    sizeof(entry->ent.ent_name));
        }
        if (baseentry->gpe_index >= table->self.ent_pmblkcnt)
                table->self.ent_pmblkcnt = baseentry->gpe_index + 1;
        KASSERT(table->self.ent_size >= table->self.ent_pmblkcnt,
            ("%s", __func__));
        KASSERT(table->self.ent_size > baseentry->gpe_index,
            ("%s", __func__));
        return (0);
}

static int
g_part_apm_create(struct g_part_table *basetable, struct g_part_parms *gpp)
{
        struct g_provider *pp;
        struct g_part_apm_table *table;
        uint32_t last;

        /* We don't nest, which means that our depth should be 0. */
        if (basetable->gpt_depth != 0)
                return (ENXIO);

        table = (struct g_part_apm_table *)basetable;
        pp = gpp->gpp_provider;
        if (pp->sectorsize != 512 ||
            pp->mediasize < (2 + 2 * basetable->gpt_entries) * pp->sectorsize)
                return (ENOSPC);

        /* APM uses 32-bit LBAs. */
        last = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX) - 1;

        basetable->gpt_first = 2 + basetable->gpt_entries;
        basetable->gpt_last = last;

        table->ddr.ddr_sig = APM_DDR_SIG;
        table->ddr.ddr_blksize = pp->sectorsize;
        table->ddr.ddr_blkcount = last + 1;

        table->self.ent_sig = APM_ENT_SIG;
        table->self.ent_pmblkcnt = basetable->gpt_entries + 1;
        table->self.ent_start = 1;
        table->self.ent_size = table->self.ent_pmblkcnt;
        strcpy(table->self.ent_name, "Apple");
        strcpy(table->self.ent_type, APM_ENT_TYPE_SELF);
        return (0);
}

static int
g_part_apm_destroy(struct g_part_table *basetable, struct g_part_parms *gpp)
{

        /* Wipe the first 2 sectors to clear the partitioning. */
        basetable->gpt_smhead |= 3;
        return (0);
}

static void
g_part_apm_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry,
    struct sbuf *sb, const char *indent)
{
        union {
                char name[APM_ENT_NAMELEN + 1];
                char type[APM_ENT_TYPELEN + 1];
        } u;
        struct g_part_apm_entry *entry;

        entry = (struct g_part_apm_entry *)baseentry;
        if (indent == NULL) {
                /* conftxt: libdisk compatibility */
                sbuf_printf(sb, " xs APPLE xt %s", entry->ent.ent_type);
        } else if (entry != NULL) {
                /* confxml: partition entry information */
                strncpy(u.name, entry->ent.ent_name, APM_ENT_NAMELEN);
                u.name[APM_ENT_NAMELEN] = '\0';
                sbuf_printf(sb, "%s<label>", indent);
                g_conf_cat_escaped(sb, u.name);
                sbuf_cat(sb, "</label>\n");
                strncpy(u.type, entry->ent.ent_type, APM_ENT_TYPELEN);
                u.type[APM_ENT_TYPELEN] = '\0';
                sbuf_printf(sb, "%s<rawtype>", indent);
                g_conf_cat_escaped(sb, u.type);
                sbuf_cat(sb, "</rawtype>\n");
        } else {
                /* confxml: scheme information */
        }
}

static int
g_part_apm_dumpto(struct g_part_table *table, struct g_part_entry *baseentry)
{
        struct g_part_apm_entry *entry;

        entry = (struct g_part_apm_entry *)baseentry;
        return ((!strcmp(entry->ent.ent_type, APM_ENT_TYPE_FREEBSD_SWAP))
            ? 1 : 0);
}

static int
g_part_apm_modify(struct g_part_table *basetable,
    struct g_part_entry *baseentry, struct g_part_parms *gpp)
{
        struct g_part_apm_entry *entry;
        int error;

        entry = (struct g_part_apm_entry *)baseentry;
        if (gpp->gpp_parms & G_PART_PARM_LABEL) {
                if (strlen(gpp->gpp_label) > sizeof(entry->ent.ent_name))
                        return (EINVAL);
        }
        if (gpp->gpp_parms & G_PART_PARM_TYPE) {
                error = apm_parse_type(gpp->gpp_type, entry->ent.ent_type,
                    sizeof(entry->ent.ent_type));
                if (error)
                        return (error);
        }
        if (gpp->gpp_parms & G_PART_PARM_LABEL) {
                strncpy(entry->ent.ent_name, gpp->gpp_label,
                    sizeof(entry->ent.ent_name));
        }
        return (0);
}

static int
g_part_apm_resize(struct g_part_table *basetable,
    struct g_part_entry *baseentry, struct g_part_parms *gpp)
{
        struct g_part_apm_entry *entry;
        struct g_provider *pp;

        if (baseentry == NULL) {
                pp = LIST_FIRST(&basetable->gpt_gp->consumer)->provider;
                basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize,
                    UINT32_MAX) - 1;
                return (0);
        }

        entry = (struct g_part_apm_entry *)baseentry;
        baseentry->gpe_end = baseentry->gpe_start + gpp->gpp_size - 1;
        entry->ent.ent_size = gpp->gpp_size;

        return (0);
}

static const char *
g_part_apm_name(struct g_part_table *table, struct g_part_entry *baseentry,
    char *buf, size_t bufsz)
{

        snprintf(buf, bufsz, "s%d", baseentry->gpe_index + 1);
        return (buf);
}

static int
g_part_apm_probe(struct g_part_table *basetable, struct g_consumer *cp)
{
        struct g_provider *pp;
        struct g_part_apm_table *table;
        char *buf;
        int error;

        /* We don't nest, which means that our depth should be 0. */
        if (basetable->gpt_depth != 0)
                return (ENXIO);

        table = (struct g_part_apm_table *)basetable;
        table->tivo_series1 = 0;
        pp = cp->provider;

        /* Sanity-check the provider. */
        if (pp->mediasize < 4 * pp->sectorsize)
                return (ENOSPC);

        /* Check that there's a Driver Descriptor Record (DDR). */
        buf = g_read_data(cp, 0L, pp->sectorsize, &error);
        if (buf == NULL)
                return (error);
        if (be16dec(buf) == APM_DDR_SIG) {
                /* Normal Apple DDR */
                table->ddr.ddr_sig = be16dec(buf);
                table->ddr.ddr_blksize = be16dec(buf + 2);
                table->ddr.ddr_blkcount = be32dec(buf + 4);
                g_free(buf);
                if (table->ddr.ddr_blksize != pp->sectorsize)
                        return (ENXIO);
                if (table->ddr.ddr_blkcount > pp->mediasize / pp->sectorsize)
                        return (ENXIO);
        } else {
                /*
                 * Check for Tivo drives, which have no DDR and a different
                 * signature.  Those whose first two bytes are 14 92 are
                 * Series 2 drives, and aren't supported.  Those that start
                 * with 92 14 are series 1 drives and are supported.
                 */
                if (be16dec(buf) != 0x9214) {
                        /* If this is 0x1492 it could be a series 2 drive */
                        g_free(buf);
                        return (ENXIO);
                }
                table->ddr.ddr_sig = APM_DDR_SIG;               /* XXX */
                table->ddr.ddr_blksize = pp->sectorsize;        /* XXX */
                table->ddr.ddr_blkcount =
                    MIN(pp->mediasize / pp->sectorsize, UINT32_MAX);
                table->tivo_series1 = 1;
                g_free(buf);
        }

        /* Check that there's a Partition Map. */
        error = apm_read_ent(cp, 1, &table->self, table->tivo_series1);
        if (error)
                return (error);
        if (table->self.ent_sig != APM_ENT_SIG)
                return (ENXIO);
        if (strcmp(table->self.ent_type, APM_ENT_TYPE_SELF))
                return (ENXIO);
        if (table->self.ent_pmblkcnt >= table->ddr.ddr_blkcount)
                return (ENXIO);
        return (G_PART_PROBE_PRI_NORM);
}

static int
g_part_apm_read(struct g_part_table *basetable, struct g_consumer *cp)
{
        struct apm_ent ent;
        struct g_part_apm_entry *entry;
        struct g_part_apm_table *table;
        int error, index;

        table = (struct g_part_apm_table *)basetable;

        basetable->gpt_first = table->self.ent_size + 1;
        basetable->gpt_last = table->ddr.ddr_blkcount - 1;
        basetable->gpt_entries = table->self.ent_size - 1;

        for (index = table->self.ent_pmblkcnt - 1; index > 0; index--) {
                error = apm_read_ent(cp, index + 1, &ent, table->tivo_series1);
                if (error)
                        continue;
                if (!strcmp(ent.ent_type, APM_ENT_TYPE_UNUSED))
                        continue;
                entry = (struct g_part_apm_entry *)g_part_new_entry(basetable,
                    index, ent.ent_start, ent.ent_start + ent.ent_size - 1);
                entry->ent = ent;
        }

        return (0);
}

static const char *
g_part_apm_type(struct g_part_table *basetable, struct g_part_entry *baseentry,
    char *buf, size_t bufsz)
{
        struct g_part_apm_entry *entry;
        const char *type;
        size_t len;

        entry = (struct g_part_apm_entry *)baseentry;
        type = entry->ent.ent_type;
        if (!strcmp(type, APM_ENT_TYPE_APPLE_BOOT))
                return (g_part_alias_name(G_PART_ALIAS_APPLE_BOOT));
        if (!strcmp(type, APM_ENT_TYPE_APPLE_HFS))
                return (g_part_alias_name(G_PART_ALIAS_APPLE_HFS));
        if (!strcmp(type, APM_ENT_TYPE_APPLE_UFS))
                return (g_part_alias_name(G_PART_ALIAS_APPLE_UFS));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD_NANDFS))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD_NANDFS));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD_SWAP))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD_SWAP));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD_UFS))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD_UFS));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD_VINUM))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD_VINUM));
        if (!strcmp(type, APM_ENT_TYPE_FREEBSD_ZFS))
                return (g_part_alias_name(G_PART_ALIAS_FREEBSD_ZFS));
        buf[0] = '!';
        len = MIN(sizeof(entry->ent.ent_type), bufsz - 2);
        bcopy(type, buf + 1, len);
        buf[len + 1] = '\0';
        return (buf);
}

static int
g_part_apm_write(struct g_part_table *basetable, struct g_consumer *cp)
{
        struct g_provider *pp;
        struct g_part_entry *baseentry;
        struct g_part_apm_entry *entry;
        struct g_part_apm_table *table;
        char *buf, *ptr;
        uint32_t index;
        int error;
        size_t tblsz;

        pp = cp->provider;
        table = (struct g_part_apm_table *)basetable;
        /*
         * Tivo Series 1 disk partitions are currently read-only.
         */
        if (table->tivo_series1)
                return (EOPNOTSUPP);

        /* Write the DDR only when we're newly created. */
        if (basetable->gpt_created) {
                buf = g_malloc(pp->sectorsize, M_WAITOK | M_ZERO);
                be16enc(buf, table->ddr.ddr_sig);
                be16enc(buf + 2, table->ddr.ddr_blksize);
                be32enc(buf + 4, table->ddr.ddr_blkcount);
                error = g_write_data(cp, 0, buf, pp->sectorsize);
                g_free(buf);
                if (error)
                        return (error);
        }

        /* Allocate the buffer for all entries */
        tblsz = table->self.ent_pmblkcnt;
        buf = g_malloc(tblsz * pp->sectorsize, M_WAITOK | M_ZERO);

        /* Fill the self entry */
        be16enc(buf, APM_ENT_SIG);
        be32enc(buf + 4, table->self.ent_pmblkcnt);
        be32enc(buf + 8, table->self.ent_start);
        be32enc(buf + 12, table->self.ent_size);
        bcopy(table->self.ent_name, buf + 16, sizeof(table->self.ent_name));
        bcopy(table->self.ent_type, buf + 48, sizeof(table->self.ent_type));

        baseentry = LIST_FIRST(&basetable->gpt_entry);
        for (index = 1; index < tblsz; index++) {
                entry = (baseentry != NULL && index == baseentry->gpe_index)
                    ? (struct g_part_apm_entry *)baseentry : NULL;
                ptr = buf + index * pp->sectorsize;
                be16enc(ptr, APM_ENT_SIG);
                be32enc(ptr + 4, table->self.ent_pmblkcnt);
                if (entry != NULL && !baseentry->gpe_deleted) {
                        be32enc(ptr + 8, entry->ent.ent_start);
                        be32enc(ptr + 12, entry->ent.ent_size);
                        bcopy(entry->ent.ent_name, ptr + 16,
                            sizeof(entry->ent.ent_name));
                        bcopy(entry->ent.ent_type, ptr + 48,
                            sizeof(entry->ent.ent_type));
                } else {
                        strcpy(ptr + 48, APM_ENT_TYPE_UNUSED);
                }
                if (entry != NULL)
                        baseentry = LIST_NEXT(baseentry, gpe_entry);
        }

        for (index = 0; index < tblsz; index += maxphys / pp->sectorsize) {
                error = g_write_data(cp, (1 + index) * pp->sectorsize,
                    buf + index * pp->sectorsize,
                    (tblsz - index > maxphys / pp->sectorsize) ? maxphys:
                    (tblsz - index) * pp->sectorsize);
                if (error) {
                        g_free(buf);
                        return (error);
                }
        }
        g_free(buf);
        return (0);
}