/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Rock Ridge extensions to the System Use Sharing protocol
 * for the High Sierra filesystem
 */

#include <sys/types.h>
#include <sys/t_lock.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kmem.h>
#include <sys/signal.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/disp.h>
#include <sys/buf.h>
#include <sys/pathname.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/conf.h>
#include <sys/stat.h>
#include <sys/mode.h>
#include <sys/mkdev.h>
#include <sys/ddi.h>

#include <vm/page.h>

#include <sys/fs/hsfs_spec.h>
#include <sys/fs/hsfs_isospec.h>
#include <sys/fs/hsfs_node.h>
#include <sys/fs/hsfs_impl.h>
#include <sys/fs/hsfs_susp.h>
#include <sys/fs/hsfs_rrip.h>

#include <sys/statvfs.h>
#include <sys/mount.h>
#include <sys/swap.h>
#include <sys/errno.h>
#include <sys/debug.h>
#include "fs/fs_subr.h"
#include <sys/cmn_err.h>

static void form_time(int, uchar_t *, struct timeval *);
static void name_parse(int, uchar_t *, size_t, uchar_t *, int *,
    ulong_t *, int);

/*
 *  Signature table for RRIP
 */
ext_signature_t  rrip_signature_table[ ] = {
        RRIP_CL,        rrip_child_link,
        RRIP_NM,        rrip_name,
        RRIP_PL,        rrip_parent_link,
        RRIP_PN,        rrip_dev_nodes,
        RRIP_PX,        rrip_file_attr,
        RRIP_RE,        rrip_reloc_dir,
        RRIP_RR,        rrip_rock_ridge,
        RRIP_SL,        rrip_sym_link,
        RRIP_TF,        rrip_file_time,
        (char *)NULL,   NULL
};


/*
 * rrip_dev_nodes()
 *
 * sig_handler() for RRIP signature "PN"
 *
 * This function parses out the major and minor numbers from the "PN
 * " SUF.
 */
uchar_t *
rrip_dev_nodes(sig_args_t *sig_args_p)
{
        uchar_t *pn_ptr = sig_args_p->SUF_ptr;
        major_t major_dev = (major_t)RRIP_MAJOR(pn_ptr);
        minor_t minor_dev = (minor_t)RRIP_MINOR(pn_ptr);

        sig_args_p->hdp->r_dev = makedevice(major_dev, minor_dev);

        return (pn_ptr + SUF_LEN(pn_ptr));
}

/*
 * rrip_file_attr()
 *
 * sig_handler() for RRIP signature "PX"
 *
 * This function parses out the file attributes of a file from the "PX"
 * SUF.  The attributes is finds are : st_mode, st_nlink, st_uid,
 * and st_gid.
 */
uchar_t *
rrip_file_attr(sig_args_t *sig_args_p)
{
        uchar_t *px_ptr = sig_args_p->SUF_ptr;
        struct hs_direntry *hdp    = sig_args_p->hdp;

        hdp->mode  = RRIP_MODE(px_ptr);
        hdp->nlink = RRIP_NLINK(px_ptr);
        hdp->uid   = RRIP_UID(px_ptr);
        hdp->gid   = RRIP_GID(px_ptr);

        if (SUF_LEN(px_ptr) >= RRIP_PX_SIZE)
                hdp->inode = (ino64_t)RRIP_INO(px_ptr);
        else
                hdp->inode = 0;

        hdp->type = IFTOVT(hdp->mode);

        return (px_ptr + SUF_LEN(px_ptr));
}

/*
 * rrip_file_time()
 *
 * support function for rrip_file_time()
 *
 * This function decides whether to parse the times in a long time form
 * (17 bytes) or a short time form (7 bytes).  These time formats are
 * defined in the ISO 9660 specification.
 */
static void
form_time(int time_length, uchar_t *file_time, struct timeval *tvp)
{
        if (time_length == ISO_DATE_LEN)
                hs_parse_longdate(file_time, tvp);
        else
                hs_parse_dirdate(file_time, tvp);

}

/*
 * rrip_file_time()
 *
 * sig_handler() for RRIP signature RRIP_TF
 *
 * This function parses out the file time attributes of a file from the
 * "TI" SUF.  The times it parses are : st_mtime, st_atime and st_ctime.
 *
 * The function form_time is a support function only used in this
 * function.
 */
uchar_t *
rrip_file_time(sig_args_t *sig_args_p)
{
        uchar_t *tf_ptr = sig_args_p->SUF_ptr;

        if (IS_TIME_BIT_SET(RRIP_TF_FLAGS(tf_ptr), RRIP_TF_ACCESS_BIT)) {
                form_time(RRIP_TF_TIME_LENGTH(tf_ptr),
                    RRIP_tf_access(tf_ptr),
                    &sig_args_p->hdp->adate);
        }

        if (IS_TIME_BIT_SET(RRIP_TF_FLAGS(tf_ptr), RRIP_TF_MODIFY_BIT)) {
                form_time(RRIP_TF_TIME_LENGTH(tf_ptr), RRIP_tf_modify(tf_ptr),
                    &sig_args_p->hdp->mdate);
        }

        if (IS_TIME_BIT_SET(RRIP_TF_FLAGS(tf_ptr), RRIP_TF_ATTRIBUTES_BIT)) {
                form_time(RRIP_TF_TIME_LENGTH(tf_ptr),
                    RRIP_tf_attributes(tf_ptr),
                    &sig_args_p->hdp->cdate);
        }

        return (tf_ptr + SUF_LEN(tf_ptr));
}



/*
 * name_parse()
 *
 * This is a generic fuction used for sym links and filenames.  The
 * flags passed to it effect the way the name/component field is parsed.
 *
 * The return value will be the NAME_CONTINUE or NAME_CHANGE value.
 *
 */
static void
name_parse(
        int             rrip_flags,     /* component/name flag */
        uchar_t         *SUA_string,    /* string from SUA */
        size_t          SUA_string_len, /* length of SUA string */
        uchar_t         *dst,           /* string to copy to */
        int             *dst_lenp,      /* ptr to cur. str len */
        ulong_t         *name_flags_p,  /* internal name flags */
        int             dst_size)       /* limit dest string to */
                                                /* this value */
{
        size_t  off;
        size_t  len;

        if (IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_ROOT))
                dst[0] = 0;

        if (IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_CURRENT)) {
                SUA_string = (uchar_t *)".";
                SUA_string_len = 1;
        }

        if (IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_PARENT)) {
                SUA_string = (uchar_t *)"..";
                SUA_string_len = 2;
        }

        /*
         * XXX
         * For now, ignore the following flags and return.
         * have to figure out how to get host name in kernel.
         * Unsure if this even should be done.
         */
        if (IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_VOLROOT) ||
            IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_HOST)) {
                cmn_err(CE_NOTE,
                        "VOLUME ROOT and NAME_HOST currently unsupported\n");
                return;
        }

        /*
         * strlcat() has two nice properties:
         * - the size of the output buffer includes the trailing '\0'
         * - we pass "total size" not "remaining size"
         * It'd be the ideal candidate for this codeblock - make it:
         *
         *      strlcat(dst, SUA_string,
         *          MIN(dstsize, strlen(dst) + SUA_string_len + 1));
         *
         * Unfortunately, strlcat() cannot deal with input strings
         * that are not NULL-terminated - like SUA_string can be in
         * our case here. So we can't use it :(
         * Now strncat() doesn't work either - because it doesn't deal
         * with strings for which the 'potential NULL-termination' isn't
         * accessible - strncat(dst, NULL, 0) crashes although it copies
         * nothing in any case. If the SUA ends on a mapping boundary,
         * then telling strncat() to copy no more than the remaining bytes
         * in the buffer is of no avail if there's no NULL byte in them.
         *
         * Hence - binary copy. What are all these str* funcs for ??
         */
        dst_size--;     /* trailing '\0' */

        off = strlen((char *)dst);
        len = MIN(dst_size - off, SUA_string_len);
        bcopy((char *)SUA_string, (char *)(dst + off), len);
        dst[off + len] = '\0';
        *dst_lenp = strlen((char *)dst);

        if (IS_NAME_BIT_SET(rrip_flags, RRIP_NAME_CONTINUE))
                SET_NAME_BIT(*(name_flags_p), RRIP_NAME_CONTINUE);
        else
                SET_NAME_BIT(*(name_flags_p), RRIP_NAME_CHANGE);

}

/*
 * rrip_name()
 *
 * sig_handler() for RRIP signature RRIP_NM
 *
 * This function handles the name of the current file.  It is case
 * sensitive to whatever was put into the field and does NO
 * translation. It will take whatever characters were in the field.
 *
 * Because the flags effect the way the name is parsed the same way
 * that the sym_link component parsing is done, we will use the same
 * function to do the actual parsing.
 */
uchar_t  *
rrip_name(sig_args_t *sig_args_p)
{
        uchar_t *nm_ptr = sig_args_p->SUF_ptr;

        if ((sig_args_p->name_p == (uchar_t *)NULL) ||
            (sig_args_p->name_len_p == (int *)NULL))
                goto end;
        /*
         * If we have a "." or ".." directory, we should not look for
         * an alternate name
         */
        if (HDE_NAME_LEN(sig_args_p->dirp) == 1) {
                if (*((char *)HDE_name(sig_args_p->dirp)) == '\0') {
                        (void) strcpy((char *)sig_args_p->name_p, ".");
                        *sig_args_p->name_len_p = 1;
                        goto end;
                } else if (*((char *)HDE_name(sig_args_p->dirp)) == '\1') {
                        (void) strcpy((char *)sig_args_p->name_p, "..");
                        *sig_args_p->name_len_p = 2;
                        goto end;
                }
        }

        name_parse((int)RRIP_NAME_FLAGS(nm_ptr), RRIP_name(nm_ptr),
            (size_t)RRIP_NAME_LEN(nm_ptr), sig_args_p->name_p,
            sig_args_p->name_len_p, &(sig_args_p->name_flags),
            MAXNAMELEN);

end:
        return (nm_ptr + SUF_LEN(nm_ptr));
}


/*
 * rrip_sym_link()
 *
 * sig_handler() for RRIP signature RRIP_SL
 *
 * creates a symlink buffer to simulate sym_links.
 */
uchar_t *
rrip_sym_link(sig_args_t *sig_args_p)
{
        uchar_t *sl_ptr = sig_args_p->SUF_ptr;
        uchar_t *comp_ptr;
        char    *tmp_sym_link;
        struct hs_direntry *hdp = sig_args_p->hdp;
        int     sym_link_len;
        char    *sym_link;

        if (hdp->type != VLNK)
                goto end;

        /*
         * If the sym link has already been created, don't recreate it
         */
        if (IS_NAME_BIT_SET(sig_args_p->name_flags, RRIP_SYM_LINK_COMPLETE))
                goto end;

        sym_link = kmem_alloc(MAXPATHLEN + 1, KM_SLEEP);

        /*
         * If there is an original string put it into sym_link[], otherwise
         * initialize sym_link[] to the empty string.
         */
        if (hdp->sym_link != (char *)NULL) {
                sym_link_len = (int)strlen(strcpy(sym_link, hdp->sym_link));
        } else {
                sym_link[0] = '\0';
                sym_link_len = 0;
        }

        /* for all components */
        for (comp_ptr = RRIP_sl_comp(sl_ptr);
            comp_ptr < (sl_ptr + SUF_LEN(sl_ptr));
            comp_ptr += RRIP_COMP_LEN(comp_ptr)) {

                name_parse((int)RRIP_COMP_FLAGS(comp_ptr),
                    RRIP_comp(comp_ptr),
                    (size_t)RRIP_COMP_NAME_LEN(comp_ptr), (uchar_t *)sym_link,
                    &sym_link_len, &(sig_args_p->name_flags),
                    MAXPATHLEN);

                /*
                 * If the component is continued don't put a '/' in
                 * the pathname, but do NULL terminate it.
                 */
                if (IS_NAME_BIT_SET(RRIP_COMP_FLAGS(comp_ptr),
                    RRIP_NAME_CONTINUE)) {
                        sym_link[sym_link_len] = '\0';
                } else {
                        sym_link[sym_link_len] = '/';
                        sym_link[sym_link_len + 1] = '\0';

                        /* add 1 to sym_link_len for '/' */
                        sym_link_len++;
                }

        }

        /*
         * If we reached the end of the symbolic link, take out the
         * last slash, but don't change ROOT "/" to an empty string.
         */
        if (!IS_NAME_BIT_SET(RRIP_SL_FLAGS(sl_ptr), RRIP_NAME_CONTINUE) &&
            sym_link_len > 1 && sym_link[sym_link_len - 1] == '/')
                sym_link[--sym_link_len] = '\0';

        /*
         * if no memory has been allocated, get some, otherwise, append
         * to the current allocation
         */

        tmp_sym_link = kmem_alloc(SYM_LINK_LEN(sym_link), KM_SLEEP);

        (void) strcpy(tmp_sym_link, sym_link);

        if (hdp->sym_link != (char *)NULL)
                kmem_free(hdp->sym_link, (size_t)(hdp->ext_size + 1));

        hdp->sym_link = (char *)&tmp_sym_link[0];
        /* the size of a symlink is its length */
        hdp->ext_size = (uint_t)strlen(tmp_sym_link);

        if (!IS_NAME_BIT_SET(RRIP_SL_FLAGS(sl_ptr), RRIP_NAME_CONTINUE)) {
                /* reached the end of the symbolic link */
                SET_NAME_BIT(sig_args_p->name_flags, RRIP_SYM_LINK_COMPLETE);
        }

        kmem_free(sym_link, MAXPATHLEN + 1);
end:
        return (sl_ptr + SUF_LEN(sl_ptr));
}

/*
 * rrip_namecopy()
 *
 * This function will copy the rrip name to the "to" buffer, if it
 * exists.
 *
 * XXX -  We should speed this up by implementing the search in
 * parse_sua().  It works right now, so I don't want to mess with it.
 */
int
rrip_namecopy(
        char    *from,                  /* name to copy */
        char    *to,                    /* string to copy "from" to */
        char    *tmp_name,              /* temp storage for original name */
        uchar_t *dirp,                  /* directory entry pointer */
        uint_t  last_offset,            /* last index into current dir block */
        struct  hsfs *fsp,              /* filesystem pointer */
        struct  hs_direntry *hdp)       /* directory entry pointer to put */
                                        /* all that good info in */
{
        int     size = 0;
        int     change_flag = 0;
        int     ret_val;

        if ((to == (char *)NULL) ||
            (from == (char *)NULL) ||
            (dirp == (uchar_t *)NULL)) {
                return (0);
        }

        /* special handling for '.' and '..' */

        if (HDE_NAME_LEN(dirp) == 1) {
                if (*((char *)HDE_name(dirp)) == '\0') {
                        (void) strcpy(to, ".");
                        return (1);
                } else if (*((char *)HDE_name(dirp)) == '\1') {
                        (void) strcpy(to, "..");
                        return (2);
                }
        }


        ret_val = parse_sua((uchar_t *)to, &size, &change_flag,
            dirp, last_offset, hdp, fsp, NULL, 0);

        if (IS_NAME_BIT_SET(change_flag, RRIP_NAME_CHANGE) && !ret_val)
                return (size);

        /*
         * Well, the name was not found
         *
         * make rripname an upper case "nm" (to), so that
         * we can compare it the current HDE_DIR_NAME()
         * without nuking the original "nm", for future case
         * sensitive name comparing
         */
        (void) strcpy(tmp_name, from);          /* keep original */
        size = hs_uppercase_copy(tmp_name, from, (int)strlen(from));

        return (-1);
}



/*
 * rrip_reloc_dir()
 *
 * This function is fairly bogus.  All it does is cause a failure of
 * the hs_parsedir, so that no vnode will be made for it and
 * essentially, the directory will no longer be seen.  This is part
 * of the directory hierarchy mess, where the relocated directory will
 * be hidden as far as ISO 9660 is concerned.  When we hit the child
 * link "CL" SUF, then we will read the new directory.
 */
uchar_t *
rrip_reloc_dir(sig_args_t *sig_args_p)
{
        uchar_t *re_ptr = sig_args_p->SUF_ptr;

        sig_args_p->flags = RELOC_DIR;

        return (re_ptr + SUF_LEN(re_ptr));
}



/*
 * rrip_child_link()
 *
 * This is the child link part of the directory hierarchy stuff and
 * this does not really do much anyway.  All it does is read the
 * directory entry that the child link SUF contains.  All should be
 * fine then.
 */
uchar_t *
rrip_child_link(sig_args_t *sig_args_p)
{
        uchar_t *cl_ptr = sig_args_p->SUF_ptr;

        sig_args_p->hdp->ext_lbn = RRIP_CHILD_LBN(cl_ptr);

        hs_filldirent(sig_args_p->fsp->hsfs_rootvp, sig_args_p->hdp);

        sig_args_p->flags = 0;

        return (cl_ptr + SUF_LEN(cl_ptr));
}


/*
 * rrip_parent_link()
 *
 * This is the parent link part of the directory hierarchy stuff and
 * this does not really do much anyway.  All it does is read the
 * directory entry that the parent link SUF contains.  All should be
 * fine then.
 */
uchar_t *
rrip_parent_link(sig_args_t *sig_args_p)
{
        uchar_t *pl_ptr = sig_args_p->SUF_ptr;

        sig_args_p->hdp->ext_lbn = RRIP_PARENT_LBN(pl_ptr);

        hs_filldirent(sig_args_p->fsp->hsfs_rootvp, sig_args_p->hdp);

        sig_args_p->flags = 0;

        return (pl_ptr + SUF_LEN(pl_ptr));
}


/*
 * rrip_rock_ridge()
 *
 * This function is supposed to aid in speed of the filesystem.
 *
 * XXX - It is only here as a place holder so far.
 */
uchar_t *
rrip_rock_ridge(sig_args_t *sig_args_p)
{
        uchar_t *rr_ptr = sig_args_p->SUF_ptr;

        return (rr_ptr + SUF_LEN(rr_ptr));
}