/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1980, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Robert Elz at The University of Melbourne.
 *
 * 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.
 */

/*
 * Fix up / report on disk quotas & usage
 */
#include <sys/param.h>
#include <sys/disklabel.h>
#include <sys/mount.h>
#include <sys/stat.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/quota.h>
#include <ufs/ffs/fs.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <fstab.h>
#include <grp.h>
#include <libufs.h>
#include <libutil.h>
#include <pwd.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "quotacheck.h"

const char *qfname = QUOTAFILENAME;
const char *qfextension[] = INITQFNAMES;
const char *quotagroup = QUOTAGROUP;

union {
        struct  fs      sblk;
        char    dummy[MAXBSIZE];
} sb_un;
#define sblock  sb_un.sblk
union {
        struct  cg      cgblk;
        char    dummy[MAXBSIZE];
} cg_un;
#define cgblk   cg_un.cgblk
long dev_bsize = 1;
ino_t maxino;

#define DIP(dp, field) \
        ((sblock.fs_magic == FS_UFS1_MAGIC) ? \
        (dp)->dp1.field : (dp)->dp2.field)

#define HASUSR  1
#define HASGRP  2

struct fileusage {
        struct  fileusage *fu_next;
        u_long  fu_curinodes;
        u_long  fu_curblocks;
        u_long  fu_id;
        char    fu_name[1];
        /* actually bigger */
};
#define FUHASH 1024     /* must be power of two */
struct fileusage *fuhead[MAXQUOTAS][FUHASH];

int     aflag;                  /* all file systems */
int     cflag;                  /* convert format to 32 or 64 bit size */
int     gflag;                  /* check group quotas */
int     uflag;                  /* check user quotas */
int     vflag;                  /* verbose */
int     fi;                     /* open disk file descriptor */

struct fileusage *
         addid(u_long, int, char *, const char *);
void     blkread(ufs2_daddr_t, char *, long);
void     freeinodebuf(void);
union dinode *
         getnextinode(ino_t);
int      getquotagid(void);
struct fileusage *
         lookup(u_long, int);
int      oneof(char *, char*[], int);
void     printchanges(const char *, int, struct dqblk *, struct fileusage *,
            u_long);
void     setinodebuf(ino_t);
int      update(const char *, struct quotafile *, int);
void     usage(void);

int
main(int argc, char *argv[])
{
        struct fstab *fs;
        struct passwd *pw;
        struct group *gr;
        struct quotafile *qfu, *qfg;
        int i, argnum, maxrun, errs, ch;
        long done = 0;
        char *name;

        errs = maxrun = 0;
        while ((ch = getopt(argc, argv, "ac:guvl:")) != -1) {
                switch(ch) {
                case 'a':
                        aflag++;
                        break;
                case 'c':
                        if (cflag)
                                usage();
                        cflag = atoi(optarg);
                        break;
                case 'g':
                        gflag++;
                        break;
                case 'u':
                        uflag++;
                        break;
                case 'v':
                        vflag++;
                        break;
                case 'l':
                        maxrun = atoi(optarg);
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if ((argc == 0 && !aflag) || (argc > 0 && aflag))
                usage();
        if (cflag && cflag != 32 && cflag != 64)
                usage();
        if (!gflag && !uflag) {
                gflag++;
                uflag++;
        }
        if (gflag) {
                setgrent();
                while ((gr = getgrent()) != NULL)
                        (void) addid((u_long)gr->gr_gid, GRPQUOTA, gr->gr_name,
                            NULL);
                endgrent();
        }
        if (uflag) {
                setpwent();
                while ((pw = getpwent()) != NULL)
                        (void) addid((u_long)pw->pw_uid, USRQUOTA, pw->pw_name,
                            NULL);
                endpwent();
        }
        /*
         * The maxrun (-l) option is now deprecated.
         */
        if (maxrun > 0)
                warnx("the -l option is now deprecated");
        if (aflag)
                exit(checkfstab(uflag, gflag));
        if (setfsent() == 0)
                errx(1, "%s: can't open", FSTAB);
        while ((fs = getfsent()) != NULL) {
                if (((argnum = oneof(fs->fs_file, argv, argc)) >= 0 ||
                     (argnum = oneof(fs->fs_spec, argv, argc)) >= 0) &&
                    (name = blockcheck(fs->fs_spec))) {
                        done |= 1 << argnum;
                        qfu = NULL;
                        if (uflag)
                                qfu = quota_open(fs, USRQUOTA, O_CREAT|O_RDWR);
                        qfg = NULL;
                        if (gflag)
                                qfg = quota_open(fs, GRPQUOTA, O_CREAT|O_RDWR);
                        if (qfu == NULL && qfg == NULL)
                                continue;
                        errs += chkquota(name, qfu, qfg);
                        if (qfu)
                                quota_close(qfu);
                        if (qfg)
                                quota_close(qfg);
                }
        }
        endfsent();
        for (i = 0; i < argc; i++)
                if ((done & (1 << i)) == 0)
                        fprintf(stderr, "%s not found in %s\n",
                                argv[i], FSTAB);
        exit(errs);
}

void
usage(void)
{
        (void)fprintf(stderr, "%s\n%s\n",
                "usage: quotacheck [-guv] [-c 32 | 64] [-l maxrun] -a",
                "       quotacheck [-guv] [-c 32 | 64] filesystem ...");
        exit(1);
}

/*
 * Scan the specified file system to check quota(s) present on it.
 */
int
chkquota(char *specname, struct quotafile *qfu, struct quotafile *qfg)
{
        struct fileusage *fup;
        union dinode *dp;
        struct fs *fs;
        int i, ret, mode, errs = 0;
        u_int32_t cg;
        ino_t curino, ino, inosused, userino = 0, groupino = 0;
        dev_t dev, userdev = 0, groupdev = 0;
        struct stat sb;
        const char *mntpt;
        char *cp;

        if (qfu != NULL)
                mntpt = quota_fsname(qfu);
        else if (qfg != NULL)
                mntpt = quota_fsname(qfg);
        else
                errx(1, "null quotafile information passed to chkquota()\n");
        if (cflag) {
                if (vflag && qfu != NULL)
                        printf("%s: convert user quota to %d bits\n",
                            mntpt, cflag);
                if (qfu != NULL && quota_convert(qfu, cflag) < 0) {
                        if (errno == EBADF)
                                errx(1,
                                    "%s: cannot convert an active quota file",
                                    mntpt);
                        err(1, "user quota conversion to size %d failed",
                            cflag);
                }
                if (vflag && qfg != NULL)
                        printf("%s: convert group quota to %d bits\n",
                            mntpt, cflag);
                if (qfg != NULL && quota_convert(qfg, cflag) < 0) {
                        if (errno == EBADF)
                                errx(1,
                                    "%s: cannot convert an active quota file",
                                    mntpt);
                        err(1, "group quota conversion to size %d failed",
                            cflag);
                }
        }
        if ((fi = open(specname, O_RDONLY, 0)) < 0) {
                warn("%s", specname);
                return (1);
        }
        if ((stat(mntpt, &sb)) < 0) {
                warn("%s", mntpt);
                return (1);
        }
        dev = sb.st_dev;
        if (vflag) {
                (void)printf("*** Checking ");
                if (qfu)
                        (void)printf("user%s", qfg ? " and " : "");
                if (qfg)
                        (void)printf("group");
                (void)printf(" quotas for %s (%s)\n", specname, mntpt);
        }
        if (qfu) {
                if (stat(quota_qfname(qfu), &sb) == 0) {
                        userino = sb.st_ino;
                        userdev = sb.st_dev;
                }
        }
        if (qfg) {
                if (stat(quota_qfname(qfg), &sb) == 0) {
                        groupino = sb.st_ino;
                        groupdev = sb.st_dev;
                }
        }
        sync();
        if ((ret = sbget(fi, &fs, UFS_STDSB, UFS_NOCSUM)) != 0) {
                switch (ret) {
                case ENOENT:
                        warn("Cannot find file system superblock");
                        return (1);
                default:
                        warn("Unable to read file system superblock");
                        return (1);
                }
        }
        bcopy(fs, &sblock, fs->fs_sbsize);
        free(fs);
        dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
        maxino = sblock.fs_ncg * sblock.fs_ipg;
        for (cg = 0; cg < sblock.fs_ncg; cg++) {
                ino = cg * sblock.fs_ipg;
                setinodebuf(ino);
                blkread(fsbtodb(&sblock, cgtod(&sblock, cg)), (char *)(&cgblk),
                    sblock.fs_cgsize);
                if (sblock.fs_magic == FS_UFS2_MAGIC)
                        inosused = cgblk.cg_initediblk;
                else
                        inosused = sblock.fs_ipg;
                /*
                 * If we are using soft updates, then we can trust the
                 * cylinder group inode allocation maps to tell us which
                 * inodes are allocated. We will scan the used inode map
                 * to find the inodes that are really in use, and then
                 * read only those inodes in from disk.
                 */
                if (sblock.fs_flags & FS_DOSOFTDEP) {
                        if (!cg_chkmagic(&cgblk))
                                errx(1, "CG %d: BAD MAGIC NUMBER\n", cg);
                        cp = &cg_inosused(&cgblk)[(inosused - 1) / CHAR_BIT];
                        for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
                                if (*cp == 0)
                                        continue;
                                for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
                                        if (*cp & i)
                                                break;
                                        inosused--;
                                }
                                break;
                        }
                        if (inosused <= 0)
                                continue;
                }
                for (curino = 0; curino < inosused; curino++, ino++) {
                        if ((dp = getnextinode(ino)) == NULL ||
                            ino < UFS_ROOTINO ||
                            (mode = DIP(dp, di_mode) & IFMT) == 0)
                                continue;
                        /*
                         * XXX: Do not account for UIDs or GIDs that appear
                         * to be negative to prevent generating 100GB+
                         * quota files.
                         */
                        if ((int)DIP(dp, di_uid) < 0 ||
                            (int)DIP(dp, di_gid) < 0) {
                                if (vflag) {
                                        if (aflag)
                                                (void)printf("%s: ", mntpt);
                        (void)printf("out of range UID/GID (%u/%u) ino=%ju\n",
                                            DIP(dp, di_uid), DIP(dp,di_gid),
                                            (uintmax_t)ino);
                                }
                                continue;
                        }

                        /*
                         * Do not account for file system snapshot files
                         * or the actual quota data files to be consistent
                         * with how they are handled inside the kernel.
                         */
#ifdef  SF_SNAPSHOT
                        if (DIP(dp, di_flags) & SF_SNAPSHOT)
                                continue;
#endif
                        if ((ino == userino && dev == userdev) ||
                            (ino == groupino && dev == groupdev))
                                continue;
                        if (qfg) {
                                fup = addid((u_long)DIP(dp, di_gid), GRPQUOTA,
                                    NULL, mntpt);
                                fup->fu_curinodes++;
                                if (mode == IFREG || mode == IFDIR ||
                                    mode == IFLNK)
                                        fup->fu_curblocks += DIP(dp, di_blocks);
                        }
                        if (qfu) {
                                fup = addid((u_long)DIP(dp, di_uid), USRQUOTA,
                                    NULL, mntpt);
                                fup->fu_curinodes++;
                                if (mode == IFREG || mode == IFDIR ||
                                    mode == IFLNK)
                                        fup->fu_curblocks += DIP(dp, di_blocks);
                        }
                }
        }
        freeinodebuf();
        if (qfu)
                errs += update(mntpt, qfu, USRQUOTA);
        if (qfg)
                errs += update(mntpt, qfg, GRPQUOTA);
        close(fi);
        (void)fflush(stdout);
        return (errs);
}

/*
 * Update a specified quota file.
 */
int
update(const char *fsname, struct quotafile *qf, int type)
{
        struct fileusage *fup;
        u_long id, lastid, highid = 0;
        struct dqblk dqbuf;
        struct stat sb;
        static struct dqblk zerodqbuf;
        static struct fileusage zerofileusage;

        /*
         * Scan the on-disk quota file and record any usage changes.
         */
        lastid = quota_maxid(qf);
        for (id = 0; id <= lastid; id++) {
                if (quota_read(qf, &dqbuf, id) < 0)
                        dqbuf = zerodqbuf;
                if ((fup = lookup(id, type)) == NULL)
                        fup = &zerofileusage;
                if (fup->fu_curinodes || fup->fu_curblocks ||
                    dqbuf.dqb_bsoftlimit || dqbuf.dqb_bhardlimit ||
                    dqbuf.dqb_isoftlimit || dqbuf.dqb_ihardlimit)
                        highid = id;
                if (dqbuf.dqb_curinodes == fup->fu_curinodes &&
                    dqbuf.dqb_curblocks == fup->fu_curblocks) {
                        fup->fu_curinodes = 0;
                        fup->fu_curblocks = 0;
                        continue;
                }
                printchanges(fsname, type, &dqbuf, fup, id);
                dqbuf.dqb_curinodes = fup->fu_curinodes;
                dqbuf.dqb_curblocks = fup->fu_curblocks;
                (void) quota_write_usage(qf, &dqbuf, id);
                fup->fu_curinodes = 0;
                fup->fu_curblocks = 0;
        }

        /*
         * Walk the hash table looking for ids with non-zero usage
         * that are not currently recorded in the quota file. E.g.
         * ids that are past the end of the current file.
         */
        for (id = 0; id < FUHASH; id++) {
                for (fup = fuhead[type][id]; fup != NULL; fup = fup->fu_next) {
                        if (fup->fu_id <= lastid)
                                continue;
                        if (fup->fu_curinodes == 0 && fup->fu_curblocks == 0)
                                continue;
                        bzero(&dqbuf, sizeof(struct dqblk));
                        if (fup->fu_id > highid)
                                highid = fup->fu_id;
                        printchanges(fsname, type, &dqbuf, fup, fup->fu_id);
                        dqbuf.dqb_curinodes = fup->fu_curinodes;
                        dqbuf.dqb_curblocks = fup->fu_curblocks;
                        (void) quota_write_usage(qf, &dqbuf, fup->fu_id);
                        fup->fu_curinodes = 0;
                        fup->fu_curblocks = 0;
                }
        }
        /*
         * If this is old format file, then size may be smaller,
         * so ensure that we only truncate when it will make things
         * smaller, and not if it will grow an old format file.
         */
        if (highid < lastid &&
            stat(quota_qfname(qf), &sb) == 0 &&
            sb.st_size > (off_t)((highid + 2) * sizeof(struct dqblk)))
                truncate(quota_qfname(qf),
                    (((off_t)highid + 2) * sizeof(struct dqblk)));
        return (0);
}

/*
 * Check to see if target appears in list of size cnt.
 */
int
oneof(char *target, char *list[], int cnt)
{
        int i;

        for (i = 0; i < cnt; i++)
                if (strcmp(target, list[i]) == 0)
                        return (i);
        return (-1);
}

/*
 * Determine the group identifier for quota files.
 */
int
getquotagid(void)
{
        struct group *gr;

        if ((gr = getgrnam(quotagroup)) != NULL)
                return (gr->gr_gid);
        return (-1);
}

/*
 * Routines to manage the file usage table.
 *
 * Lookup an id of a specific type.
 */
struct fileusage *
lookup(u_long id, int type)
{
        struct fileusage *fup;

        for (fup = fuhead[type][id & (FUHASH-1)]; fup != NULL; fup = fup->fu_next)
                if (fup->fu_id == id)
                        return (fup);
        return (NULL);
}

/*
 * Add a new file usage id if it does not already exist.
 */
struct fileusage *
addid(u_long id, int type, char *name, const char *fsname)
{
        struct fileusage *fup, **fhp;
        int len;

        if ((fup = lookup(id, type)) != NULL)
                return (fup);
        if (name)
                len = strlen(name);
        else
                len = 0;
        if ((fup = calloc(1, sizeof(*fup) + len)) == NULL)
                errx(1, "calloc failed");
        fhp = &fuhead[type][id & (FUHASH - 1)];
        fup->fu_next = *fhp;
        *fhp = fup;
        fup->fu_id = id;
        if (name)
                bcopy(name, fup->fu_name, len + 1);
        else {
                (void)sprintf(fup->fu_name, "%lu", id);
                if (vflag) {
                        if (aflag && fsname != NULL)
                                (void)printf("%s: ", fsname);
                        printf("unknown %cid: %lu\n",
                            type == USRQUOTA ? 'u' : 'g', id);
                }
        }
        return (fup);
}

/*
 * Special purpose version of ginode used to optimize pass
 * over all the inodes in numerical order.
 */
static ino_t nextino, lastinum, lastvalidinum;
static long readcnt, readpercg, fullcnt, inobufsize, partialcnt, partialsize;
static caddr_t inodebuf;
#define INOBUFSIZE      56*1024         /* size of buffer to read inodes */

union dinode *
getnextinode(ino_t inumber)
{
        long size;
        ufs2_daddr_t dblk;
        union dinode *dp;
        static caddr_t nextinop;

        if (inumber != nextino++ || inumber > lastvalidinum)
                errx(1, "bad inode number %ju to nextinode",
                    (uintmax_t)inumber);
        if (inumber >= lastinum) {
                readcnt++;
                dblk = fsbtodb(&sblock, ino_to_fsba(&sblock, lastinum));
                if (readcnt % readpercg == 0) {
                        size = partialsize;
                        lastinum += partialcnt;
                } else {
                        size = inobufsize;
                        lastinum += fullcnt;
                }
                /*
                 * If blkread returns an error, it will already have zeroed
                 * out the buffer, so we do not need to do so here.
                 */
                blkread(dblk, inodebuf, size);
                nextinop = inodebuf;
        }
        dp = (union dinode *)nextinop;
        if (sblock.fs_magic == FS_UFS1_MAGIC)
                nextinop += sizeof(struct ufs1_dinode);
        else
                nextinop += sizeof(struct ufs2_dinode);
        return (dp);
}

/*
 * Prepare to scan a set of inodes.
 */
void
setinodebuf(ino_t inum)
{

        if (inum % sblock.fs_ipg != 0)
                errx(1, "bad inode number %ju to setinodebuf", (uintmax_t)inum);
        lastvalidinum = inum + sblock.fs_ipg - 1;
        nextino = inum;
        lastinum = inum;
        readcnt = 0;
        if (inodebuf != NULL)
                return;
        inobufsize = blkroundup(&sblock, INOBUFSIZE);
        fullcnt = inobufsize / ((sblock.fs_magic == FS_UFS1_MAGIC) ?
            sizeof(struct ufs1_dinode) : sizeof(struct ufs2_dinode));
        readpercg = sblock.fs_ipg / fullcnt;
        partialcnt = sblock.fs_ipg % fullcnt;
        partialsize = partialcnt * ((sblock.fs_magic == FS_UFS1_MAGIC) ?
            sizeof(struct ufs1_dinode) : sizeof(struct ufs2_dinode));
        if (partialcnt != 0) {
                readpercg++;
        } else {
                partialcnt = fullcnt;
                partialsize = inobufsize;
        }
        if ((inodebuf = malloc((unsigned)inobufsize)) == NULL)
                errx(1, "cannot allocate space for inode buffer");
}

/*
 * Free up data structures used to scan inodes.
 */
void
freeinodebuf(void)
{

        if (inodebuf != NULL)
                free(inodebuf);
        inodebuf = NULL;
}

/*
 * Read specified disk blocks.
 */
void
blkread(ufs2_daddr_t bno, char *buf, long cnt)
{

        if (lseek(fi, (off_t)bno * dev_bsize, SEEK_SET) < 0 ||
            read(fi, buf, cnt) != cnt)
                errx(1, "blkread failed on block %ld", (long)bno);
}

/*
 * Display updated block and i-node counts.
 */
void
printchanges(const char *fsname, int type, struct dqblk *dp,
    struct fileusage *fup, u_long id)
{
        if (!vflag)
                return;
        if (aflag)
                (void)printf("%s: ", fsname);
        if (fup->fu_name[0] == '\0')
                (void)printf("%-8lu fixed ", id);
        else
                (void)printf("%-8s fixed ", fup->fu_name);
        switch (type) {

        case GRPQUOTA:
                (void)printf("(group):");
                break;

        case USRQUOTA:
                (void)printf("(user): ");
                break;

        default:
                (void)printf("(unknown quota type %d)", type);
                break;
        }
        if (dp->dqb_curinodes != fup->fu_curinodes)
                (void)printf("\tinodes %lu -> %lu", (u_long)dp->dqb_curinodes,
                    (u_long)fup->fu_curinodes);
        if (dp->dqb_curblocks != fup->fu_curblocks)
                (void)printf("\tblocks %lu -> %lu",
                    (u_long)dp->dqb_curblocks,
                    (u_long)fup->fu_curblocks);
        (void)printf("\n");
}