/*      $OpenBSD: dirs.c,v 1.43 2024/01/09 03:16:00 guenther Exp $      */
/*      $NetBSD: dirs.c,v 1.26 1997/07/01 05:37:49 lukem Exp $  */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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/stat.h>
#include <sys/time.h>

#include <ufs/ffs/fs.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>
#include <protocols/dumprestore.h>

#include <endian.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>

#include "restore.h"
#include "extern.h"

/*
 * Symbol table of directories read from tape.
 */
#define HASHSIZE        1000
#define INOHASH(val) (val % HASHSIZE)
struct inotab {
        struct  inotab *t_next;
        ino_t   t_ino;
        int32_t t_seekpt;
        int32_t t_size;
};
static struct inotab *inotab[HASHSIZE];

/*
 * Information retained about directories.
 */
struct modeinfo {
        ino_t ino;
        struct timespec ctimep[2];
        struct timespec mtimep[2];
        mode_t mode;
        uid_t uid;
        gid_t gid;
        u_int flags;
};

/*
 * Definitions for library routines operating on directories.
 */
#undef DIRBLKSIZ
#define DIRBLKSIZ 1024
struct rstdirdesc {
        int     dd_fd;
        int32_t dd_loc;
        int32_t dd_size;
        char    dd_buf[DIRBLKSIZ];
};

/*
 * Global variables for this file.
 */
static long     seekpt;
static FILE     *df, *mf;
static RST_DIR  *dirp;
static char     dirfile[PATH_MAX] = "#";        /* No file */
static char     modefile[PATH_MAX] = "#";       /* No file */
static char     dot[2] = ".";                   /* So it can be modified */

/*
 * Format of old style directories.
 */
#define ODIRSIZ 14
struct odirect {
        u_short d_ino;
        char    d_name[ODIRSIZ];
};

static struct inotab    *allocinotab(FILE *, struct context *, long);
static void              dcvt(struct odirect *, struct direct *);
static void              flushent(void);
static struct inotab    *inotablookup(ino_t);
static RST_DIR          *opendirfile(const char *);
static void              putdir(char *, size_t);
static void              putent(struct direct *);
static void              rst_seekdir(RST_DIR *, long, long);
static long              rst_telldir(RST_DIR *);
static struct direct    *searchdir(ino_t, char *);

/*
 *      Extract directory contents, building up a directory structure
 *      on disk for extraction by name.
 *      If genmode is requested, save mode, owner, and times for all
 *      directories on the tape.
 */
void
extractdirs(int genmode)
{
        int i;
        struct inotab *itp;
        struct direct nulldir;
        int fd;

        Vprintf(stdout, "Extract directories from tape\n");
        (void)snprintf(dirfile, sizeof(dirfile), "%s/rstdir%lld", tmpdir,
            (long long)dumpdate);
        if (command != 'r' && command != 'R') {
                strlcat(dirfile, "-XXXXXXXXXX", sizeof(dirfile));
                fd = mkstemp(dirfile);
        } else
                fd = open(dirfile, O_RDWR|O_CREAT|O_EXCL, 0666);
        if (fd == -1 || (df = fdopen(fd, "w")) == NULL) {
                int saved_errno = errno;
                if (fd != -1)
                        close(fd);
                errc(1, saved_errno,
                    "cannot create directory temporary %s", dirfile);
        }
        if (genmode != 0) {
                (void)snprintf(modefile, sizeof(modefile), "%s/rstmode%lld",
                    tmpdir, (long long)dumpdate);
                if (command != 'r' && command != 'R') {
                        strlcat(modefile, "-XXXXXXXXXX", sizeof(modefile));
                        fd = mkstemp(modefile);
                } else
                        fd = open(modefile, O_RDWR|O_CREAT|O_EXCL, 0666);
                if (fd == -1 || (mf = fdopen(fd, "w")) == NULL) {
                        int saved_errno = errno;
                        if (fd != -1)
                                close(fd);
                        errc(1, saved_errno,
                            "cannot create modefile %s", modefile);
                }
        }
        nulldir.d_ino = 0;
        nulldir.d_type = DT_DIR;
        nulldir.d_namlen = 1;
        nulldir.d_name[0] = '/';
        nulldir.d_name[1] = '\0';
        nulldir.d_reclen = DIRSIZ(&nulldir);
        for (;;) {
                curfile.name = "<directory file - name unknown>";
                curfile.action = USING;
                if (curfile.mode == 0 || (curfile.mode & IFMT) != IFDIR) {
                        (void)fclose(df);
                        dirp = opendirfile(dirfile);
                        if (dirp == NULL)
                                warn("opendirfile");
                        if (mf != NULL)
                                (void)fclose(mf);
                        i = dirlookup(dot);
                        if (i == 0)
                                panic("Root directory is not on tape\n");
                        return;
                }
                itp = allocinotab(mf, &curfile, seekpt);
                getfile(putdir, xtrnull);
                putent(&nulldir);
                flushent();
                itp->t_size = seekpt - itp->t_seekpt;
        }
}

/*
 * skip over all the directories on the tape
 */
void
skipdirs(void)
{

        while (curfile.ino && (curfile.mode & IFMT) == IFDIR) {
                skipfile();
        }
}

/*
 *      Recursively find names and inumbers of all files in subtree
 *      pname and pass them off to be processed.
 */
void
treescan(char *pname, ino_t ino, long (*todo)(char *, ino_t, int))
{
        struct inotab *itp;
        struct direct *dp;
        size_t namelen;
        long bpt;
        char locname[PATH_MAX + 1];

        itp = inotablookup(ino);
        if (itp == NULL) {
                /*
                 * Pname is name of a simple file or an unchanged directory.
                 */
                (void)(*todo)(pname, ino, LEAF);
                return;
        }
        /*
         * Pname is a dumped directory name.
         */
        if ((*todo)(pname, ino, NODE) == FAIL)
                return;
        /*
         * begin search through the directory
         * skipping over "." and ".."
         */
        namelen = strlcpy(locname, pname, sizeof(locname));
        if (namelen >= sizeof(locname) - 1)
                namelen = sizeof(locname) - 2;
        locname[namelen++] = '/';
        locname[namelen] = '\0';
        rst_seekdir(dirp, itp->t_seekpt, itp->t_seekpt);
        dp = rst_readdir(dirp); /* "." */
        if (dp != NULL && strcmp(dp->d_name, ".") == 0)
                dp = rst_readdir(dirp); /* ".." */
        else
                fprintf(stderr, "Warning: `.' missing from directory %s\n",
                        pname);
        if (dp != NULL && strcmp(dp->d_name, "..") == 0)
                dp = rst_readdir(dirp); /* first real entry */
        else
                fprintf(stderr, "Warning: `..' missing from directory %s\n",
                        pname);
        bpt = rst_telldir(dirp);
        /*
         * a zero inode signals end of directory
         */
        while (dp != NULL) {
                locname[namelen] = '\0';
                if (namelen + dp->d_namlen >= sizeof(locname)) {
                        fprintf(stderr, "%s%s: name exceeds %zd char\n",
                                locname, dp->d_name, sizeof(locname) - 1);
                } else {
                        (void)strlcat(locname, dp->d_name, sizeof(locname));
                        treescan(locname, dp->d_ino, todo);
                        rst_seekdir(dirp, bpt, itp->t_seekpt);
                }
                dp = rst_readdir(dirp);
                bpt = rst_telldir(dirp);
        }
}

/*
 * Lookup a pathname which is always assumed to start from the ROOTINO.
 */
struct direct *
pathsearch(const char *pathname)
{
        ino_t ino;
        struct direct *dp;
        char *path, *name, buffer[PATH_MAX];

        strlcpy(buffer, pathname, sizeof buffer);
        path = buffer;
        ino = ROOTINO;
        while (*path == '/')
                path++;
        dp = NULL;
        while ((name = strsep(&path, "/")) != NULL && *name != '\0') {
                if ((dp = searchdir(ino, name)) == NULL)
                        return (NULL);
                ino = dp->d_ino;
        }
        return (dp);
}

/*
 * Lookup the requested name in directory inum.
 * Return its inode number if found, zero if it does not exist.
 */
static struct direct *
searchdir(ino_t inum, char *name)
{
        struct direct *dp;
        struct inotab *itp;
        int len;

        itp = inotablookup(inum);
        if (itp == NULL)
                return (NULL);
        rst_seekdir(dirp, itp->t_seekpt, itp->t_seekpt);
        len = strlen(name);
        do {
                dp = rst_readdir(dirp);
                if (dp == NULL)
                        return (NULL);
        } while (dp->d_namlen != len || strncmp(dp->d_name, name, len) != 0);
        return (dp);
}

/*
 * Put the directory entries in the directory file
 */
static void
putdir(char *buf, size_t size)
{
        struct direct cvtbuf;
        struct odirect *odp;
        struct odirect *eodp;
        struct direct *dp;
        size_t loc, i;

        if (cvtflag) {
                eodp = (struct odirect *)&buf[size];
                for (odp = (struct odirect *)buf; odp < eodp; odp++)
                        if (odp->d_ino != 0) {
                                dcvt(odp, &cvtbuf);
                                putent(&cvtbuf);
                        }
        } else {
                for (loc = 0; loc < size; ) {
                        dp = (struct direct *)(buf + loc);
                        if (Bcvt) {
                                dp->d_ino = swap32(dp->d_ino);
                                dp->d_reclen = swap16(dp->d_reclen);
                        }
                        if (oldinofmt && dp->d_ino != 0) {
#                               if BYTE_ORDER == BIG_ENDIAN
                                        if (Bcvt)
                                                dp->d_namlen = dp->d_type;
#                               else
                                        if (!Bcvt)
                                                dp->d_namlen = dp->d_type;
#                               endif
                                dp->d_type = DT_UNKNOWN;
                        }
                        i = DIRBLKSIZ - (loc & (DIRBLKSIZ - 1));
                        if ((dp->d_reclen & 0x3) != 0 ||
                            dp->d_reclen > i ||
                            dp->d_reclen < DIRSIZ(dp) ||
                            dp->d_namlen > NAME_MAX) {
                                Vprintf(stdout, "Mangled directory: ");
                                if ((dp->d_reclen & 0x3) != 0)
                                        Vprintf(stdout,
                                           "reclen not multiple of 4 ");
                                if (dp->d_reclen < DIRSIZ(dp))
                                        Vprintf(stdout,
                                           "reclen less than DIRSIZ (%u < %u) ",
                                           (unsigned)dp->d_reclen,
                                           (unsigned)DIRSIZ(dp));
                                if (dp->d_namlen > NAME_MAX)
                                        Vprintf(stdout,
                                           "reclen name too big (%u > %u) ",
                                           (unsigned)dp->d_namlen, NAME_MAX);
                                Vprintf(stdout, "\n");
                                loc += i;
                                continue;
                        }
                        loc += dp->d_reclen;
                        if (dp->d_ino != 0) {
                                putent(dp);
                        }
                }
        }
}

/*
 * These variables are "local" to the following two functions.
 */
char dirbuf[DIRBLKSIZ];
long dirloc = 0;
long prev = 0;

/*
 * add a new directory entry to a file.
 */
static void
putent(struct direct *dp)
{
        dp->d_reclen = DIRSIZ(dp);
        if (dirloc + dp->d_reclen > DIRBLKSIZ) {
                ((struct direct *)(dirbuf + prev))->d_reclen =
                    DIRBLKSIZ - prev;
                (void)fwrite(dirbuf, 1, DIRBLKSIZ, df);
                dirloc = 0;
        }
        memcpy(dirbuf + dirloc, dp, dp->d_reclen);
        prev = dirloc;
        dirloc += dp->d_reclen;
}

/*
 * flush out a directory that is finished.
 */
static void
flushent(void)
{
        ((struct direct *)(dirbuf + prev))->d_reclen = DIRBLKSIZ - prev;
        (void)fwrite(dirbuf, dirloc, 1, df);
        seekpt = ftell(df);
        dirloc = 0;
}

static void
dcvt(struct odirect *odp, struct direct *ndp)
{

        memset(ndp, 0, sizeof *ndp);
        if (Bcvt)
            ndp->d_ino = swap16(odp->d_ino);
        else
            ndp->d_ino = odp->d_ino;
        ndp->d_type = DT_UNKNOWN;
        (void)strncpy(ndp->d_name, odp->d_name, ODIRSIZ);
        ndp->d_namlen = strlen(ndp->d_name);
        ndp->d_reclen = DIRSIZ(ndp);
}

/*
 * Seek to an entry in a directory.
 * Only values returned by rst_telldir should be passed to rst_seekdir.
 * This routine handles many directories in a single file.
 * It takes the base of the directory in the file, plus
 * the desired seek offset into it.
 */
static void
rst_seekdir(RST_DIR *dirp, long loc, long base)
{

        if (loc == rst_telldir(dirp))
                return;
        loc -= base;
        if (loc < 0)
                fprintf(stderr, "bad seek pointer to rst_seekdir %ld\n", loc);
        (void)lseek(dirp->dd_fd, base + (loc & ~(DIRBLKSIZ - 1)), SEEK_SET);
        dirp->dd_loc = loc & (DIRBLKSIZ - 1);
        if (dirp->dd_loc != 0)
                dirp->dd_size = read(dirp->dd_fd, dirp->dd_buf, DIRBLKSIZ);
}

/*
 * get next entry in a directory.
 */
struct direct *
rst_readdir(RST_DIR *dirp)
{
        struct direct *dp;

        for (;;) {
                if (dirp->dd_loc == 0) {
                        dirp->dd_size = read(dirp->dd_fd, dirp->dd_buf,
                            DIRBLKSIZ);
                        if (dirp->dd_size <= 0) {
                                Dprintf(stderr, "error reading directory\n");
                                return (NULL);
                        }
                }
                if (dirp->dd_loc >= dirp->dd_size) {
                        dirp->dd_loc = 0;
                        continue;
                }
                dp = (struct direct *)(dirp->dd_buf + dirp->dd_loc);
                if (dp->d_reclen == 0 ||
                    dp->d_reclen > DIRBLKSIZ + 1 - dirp->dd_loc) {
                        Dprintf(stderr, "corrupted directory: bad reclen %d\n",
                                dp->d_reclen);
                        return (NULL);
                }
                dirp->dd_loc += dp->d_reclen;
                if (dp->d_ino == 0 && strcmp(dp->d_name, "/") == 0)
                        return (NULL);
                if (dp->d_ino >= maxino) {
                        Dprintf(stderr, "corrupted directory: bad inum %llu\n",
                            (unsigned long long)dp->d_ino);
                        continue;
                }
                return (dp);
        }
}

/*
 * Simulate the opening of a directory
 */
RST_DIR *
rst_opendir(const char *name)
{
        struct inotab *itp;
        RST_DIR *dirp;
        ino_t ino;

        if ((ino = dirlookup(name)) > 0 &&
            (itp = inotablookup(ino)) != NULL) {
                dirp = opendirfile(dirfile);
                rst_seekdir(dirp, itp->t_seekpt, itp->t_seekpt);
                return (dirp);
        }
        return (NULL);
}

/*
 * In our case, there is nothing to do when closing a directory.
 */
void
rst_closedir(RST_DIR *dirp)
{
        (void)close(dirp->dd_fd);
        free(dirp);
        return;
}

/*
 * Simulate finding the current offset in the directory.
 */
static long
rst_telldir(RST_DIR *dirp)
{
        return ((long)lseek(dirp->dd_fd,
            (off_t)0, SEEK_CUR) - dirp->dd_size + dirp->dd_loc);
}

/*
 * Open a directory file.
 */
static RST_DIR *
opendirfile(const char *name)
{
        RST_DIR *dirp;
        int fd;

        if ((fd = open(name, O_RDONLY)) == -1)
                return (NULL);
        if ((dirp = malloc(sizeof(RST_DIR))) == NULL) {
                (void)close(fd);
                return (NULL);
        }
        dirp->dd_fd = fd;
        dirp->dd_loc = 0;
        return (dirp);
}

/*
 * Set the mode, owner, and times for all new or changed directories
 */
void
setdirmodes(int flags)
{
        FILE *mf;
        struct modeinfo node;
        struct entry *ep;
        char *cp;

        Vprintf(stdout, "Set directory mode, owner, and times.\n");
        if (command == 'r' || command == 'R')
                (void)snprintf(modefile, sizeof(modefile), "%s/rstmode%lld",
                    tmpdir, (long long)dumpdate);
        if (modefile[0] == '#') {
                panic("modefile not defined\n");
                fputs("directory mode, owner, and times not set\n", stderr);
                return;
        }
        mf = fopen(modefile, "r");
        if (mf == NULL) {
                warn("fopen");
                fprintf(stderr, "cannot open mode file %s\n", modefile);
                fprintf(stderr, "directory mode, owner, and times not set\n");
                return;
        }
        clearerr(mf);
        for (;;) {
                (void)fread((char *)&node, 1, sizeof(struct modeinfo), mf);
                if (feof(mf))
                        break;
                ep = lookupino(node.ino);
                if (command == 'i' || command == 'x') {
                        if (ep == NULL)
                                continue;
                        if ((flags & FORCE) == 0 && ep->e_flags & EXISTED) {
                                ep->e_flags &= ~NEW;
                                continue;
                        }
                        if (node.ino == ROOTINO &&
                            reply("set owner/mode for '.'") == FAIL)
                                continue;
                }
                if (ep == NULL) {
                        panic("cannot find directory inode %llu\n",
                            (unsigned long long)node.ino);
                } else {
                        if (!Nflag) {
                                cp = myname(ep);
                                (void)chown(cp, node.uid, node.gid);
                                (void)chmod(cp, node.mode);
                                (void)chflags(cp, node.flags);
                                (void)utimensat(AT_FDCWD, cp, node.ctimep, 0);
                                (void)utimensat(AT_FDCWD, cp, node.mtimep, 0);
                        }
                        ep->e_flags &= ~NEW;
                }
        }
        if (ferror(mf))
                panic("error setting directory modes\n");
        (void)fclose(mf);
}

/*
 * Generate a literal copy of a directory.
 */
int
genliteraldir(char *name, ino_t ino)
{
        struct inotab *itp;
        int ofile, dp, i, size;
        char buf[BUFSIZ];

        itp = inotablookup(ino);
        if (itp == NULL)
                panic("Cannot find directory inode %llu named %s\n",
                    (unsigned long long)ino, name);
        if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC, 0666)) == -1) {
                warn("%s: cannot create file", name);
                return (FAIL);
        }
        rst_seekdir(dirp, itp->t_seekpt, itp->t_seekpt);
        dp = dup(dirp->dd_fd);
        for (i = itp->t_size; i > 0; i -= BUFSIZ) {
                size = i < BUFSIZ ? i : BUFSIZ;
                if (read(dp, buf, size) == -1)
                        err(1, "read error extracting inode %llu, name %s",
                            (unsigned long long)curfile.ino, curfile.name);
                xtrfile(buf, size);
        }
        (void)close(dp);
        (void)close(ofile);
        return (GOOD);
}

/*
 * Determine the type of an inode
 */
int
inodetype(ino_t ino)
{
        struct inotab *itp;

        itp = inotablookup(ino);
        if (itp == NULL)
                return (LEAF);
        return (NODE);
}

/*
 * Allocate and initialize a directory inode entry.
 * If requested, save its pertinent mode, owner, and time info.
 */
static struct inotab *
allocinotab(FILE *mf, struct context *ctxp, long seekpt)
{
        struct inotab   *itp;
        struct modeinfo node;

        itp = calloc(1, sizeof(struct inotab));
        if (itp == NULL)
                panic("no memory directory table\n");
        itp->t_next = inotab[INOHASH(ctxp->ino)];
        inotab[INOHASH(ctxp->ino)] = itp;
        itp->t_ino = ctxp->ino;
        itp->t_seekpt = seekpt;
        if (mf == NULL)
                return (itp);
        node.ino = ctxp->ino;
        node.mtimep[0].tv_sec = ctxp->atime_sec;
        node.mtimep[0].tv_nsec = ctxp->atime_nsec;
        node.mtimep[1].tv_sec = ctxp->mtime_sec;
        node.mtimep[1].tv_nsec = ctxp->mtime_nsec;
        node.ctimep[0].tv_sec = ctxp->atime_sec;
        node.ctimep[0].tv_nsec = ctxp->atime_nsec;
        node.ctimep[1].tv_sec = ctxp->birthtime_sec;
        node.ctimep[1].tv_nsec = ctxp->birthtime_nsec;
        node.mode = ctxp->mode;
        node.flags = ctxp->file_flags;
        node.uid = ctxp->uid;
        node.gid = ctxp->gid;
        (void)fwrite((char *)&node, 1, sizeof(struct modeinfo), mf);
        return (itp);
}

/*
 * Look up an inode in the table of directories
 */
static struct inotab *
inotablookup(ino_t ino)
{
        struct inotab *itp;

        for (itp = inotab[INOHASH(ino)]; itp != NULL; itp = itp->t_next)
                if (itp->t_ino == ino)
                        return (itp);
        return (NULL);
}

/*
 * Clean up and exit
 */
void
cleanup(void)
{

        closemt();
        if (modefile[0] != '#')
                (void)unlink(modefile);
        if (dirfile[0] != '#')
                (void)unlink(dirfile);
}