Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/vmd/ufs.c	Lines:	0	219	0.0 %
Date:	2017-11-07	Branches:	0	140	0.0 %


/*	$OpenBSD: ufs.c,v 1.5 2017/08/29 21:10:20 deraadt Exp $	*/
/*	$NetBSD: ufs.c,v 1.16 1996/09/30 16:01:22 ws Exp $	*/

/*-
 * Copyright (c) 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * The Mach Operating System project at Carnegie-Mellon University.
 *
 * 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.
 *
 *
 * Copyright (c) 1990, 1991 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Author: David Golub
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

/*
 *	Stand-alone file reading package.
 */

#include <sys/param.h>	/* DEV_BSIZE MAXBSIZE */
#include <sys/time.h>
#include <sys/stat.h>
#include <ufs/ffs/fs.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>

#include <limits.h>

#include "vmboot.h"

/* Used in the kernel by libsa */
#define alloc		malloc
#define free(_p, _n)	free(_p)
#define twiddle()	do { } while(0)
#define NO_READDIR	1

/*
 * In-core open file.
 */
struct file {
	off_t		f_seekp;	/* seek pointer */
	struct fs	*f_fs;		/* pointer to super-block */
	struct ufs1_dinode	f_di;		/* copy of on-disk inode */
	int		f_nindir[NIADDR];
					/* number of blocks mapped by
					   indirect block at level i */
	char		*f_blk[NIADDR];	/* buffer for indirect block at
					   level i */
	size_t		f_blksize[NIADDR];
					/* size of buffer */
	daddr32_t	f_blkno[NIADDR];/* disk address of block in buffer */
	char		*f_buf;		/* buffer for data block */
	size_t		f_buf_size;	/* size of data block */
	daddr32_t	f_buf_blkno;	/* block number of data block */
};

static int	read_inode(ufsino_t, struct open_file *);
static int	block_map(struct open_file *, daddr32_t, daddr32_t *);
static int	buf_read_file(struct open_file *, char **, size_t *);
static int	search_directory(char *, struct open_file *, ufsino_t *);
static int	ufs_close_internal(struct file *);
#ifdef COMPAT_UFS
static void	ffs_oldfscompat(struct fs *);
#endif

/*
 * Read a new inode into a file structure.
 */
static int
read_inode(ufsino_t inumber, struct open_file *f)
{
	struct file *fp = (struct file *)f->f_fsdata;
	struct fs *fs = fp->f_fs;
	char *buf;
	size_t rsize;
	int rc;

	/*
	 * Read inode and save it.
	 */
	buf = alloc(fs->fs_bsize);
	twiddle();
	rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
	    fsbtodb(fs, (daddr32_t)ino_to_fsba(fs, inumber)), fs->fs_bsize,
	    buf, &rsize);
	if (rc)
		goto out;
	if (rsize != (size_t)fs->fs_bsize) {
		rc = EIO;
		goto out;
	}

	{
		struct ufs1_dinode *dp;

		dp = (struct ufs1_dinode *)buf;
		fp->f_di = dp[ino_to_fsbo(fs, inumber)];
	}

	/*
	 * Clear out the old buffers
	 */
	{
		int level;

		for (level = 0; level < NIADDR; level++)
			fp->f_blkno[level] = -1;
		fp->f_buf_blkno = -1;
		fp->f_seekp = 0;
	}
out:
	free(buf, fs->fs_bsize);
	return (rc);
}

/*
 * Given an offset in a file, find the disk block number that
 * contains that block.
 */
static int
block_map(struct open_file *f, daddr32_t file_block, daddr32_t *disk_block_p)
{
	struct file *fp = (struct file *)f->f_fsdata;
	daddr32_t ind_block_num, *ind_p;
	struct fs *fs = fp->f_fs;
	int level, idx, rc;

	/*
	 * Index structure of an inode:
	 *
	 * di_db[0..NDADDR-1]	hold block numbers for blocks
	 *			0..NDADDR-1
	 *
	 * di_ib[0]		index block 0 is the single indirect block
	 *			holds block numbers for blocks
	 *			NDADDR .. NDADDR + NINDIR(fs)-1
	 *
	 * di_ib[1]		index block 1 is the double indirect block
	 *			holds block numbers for INDEX blocks for blocks
	 *			NDADDR + NINDIR(fs) ..
	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
	 *
	 * di_ib[2]		index block 2 is the triple indirect block
	 *			holds block numbers for double-indirect
	 *			blocks for blocks
	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2
	 *				+ NINDIR(fs)**3 - 1
	 */

	if (file_block < NDADDR) {
		/* Direct block. */
		*disk_block_p = fp->f_di.di_db[file_block];
		return (0);
	}

	file_block -= NDADDR;

	/*
	 * nindir[0] = NINDIR
	 * nindir[1] = NINDIR**2
	 * nindir[2] = NINDIR**3
	 *	etc
	 */
	for (level = 0; level < NIADDR; level++) {
		if (file_block < fp->f_nindir[level])
			break;
		file_block -= fp->f_nindir[level];
	}
	if (level == NIADDR) {
		/* Block number too high */
		return (EFBIG);
	}

	ind_block_num = fp->f_di.di_ib[level];

	for (; level >= 0; level--) {
		if (ind_block_num == 0) {
			*disk_block_p = 0;	/* missing */
			return (0);
		}

		if (fp->f_blkno[level] != ind_block_num) {
			if (fp->f_blk[level] == NULL)
				fp->f_blk[level] =
				    alloc(fs->fs_bsize);
			twiddle();
			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
			    fsbtodb(fp->f_fs, ind_block_num), fs->fs_bsize,
			    fp->f_blk[level], &fp->f_blksize[level]);
			if (rc)
				return (rc);
			if (fp->f_blksize[level] != (size_t)fs->fs_bsize)
				return (EIO);
			fp->f_blkno[level] = ind_block_num;
		}

		ind_p = (daddr32_t *)fp->f_blk[level];

		if (level > 0) {
			idx = file_block / fp->f_nindir[level - 1];
			file_block %= fp->f_nindir[level - 1];
		} else
			idx = file_block;

		ind_block_num = ind_p[idx];
	}

	*disk_block_p = ind_block_num;
	return (0);
}

/*
 * Read a portion of a file into an internal buffer.  Return
 * the location in the buffer and the amount in the buffer.
 */
static int
buf_read_file(struct open_file *f, char **buf_p, size_t *size_p)
{
	struct file *fp = (struct file *)f->f_fsdata;
	struct fs *fs = fp->f_fs;
	daddr32_t file_block, disk_block;
	size_t block_size;
	long off;
	int rc;

	off = blkoff(fs, fp->f_seekp);
	file_block = lblkno(fs, fp->f_seekp);
	block_size = dblksize(fs, &fp->f_di, (u_int64_t)file_block);

	if (file_block != fp->f_buf_blkno) {
		rc = block_map(f, file_block, &disk_block);
		if (rc)
			return (rc);

		if (fp->f_buf == NULL)
			fp->f_buf = alloc(fs->fs_bsize);

		if (disk_block == 0) {
			bzero(fp->f_buf, block_size);
			fp->f_buf_size = block_size;
		} else {
			twiddle();
			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
			    fsbtodb(fs, disk_block),
			    block_size, fp->f_buf, &fp->f_buf_size);
			if (rc)
				return (rc);
		}

		fp->f_buf_blkno = file_block;
	}

	/*
	 * Return address of byte in buffer corresponding to
	 * offset, and size of remainder of buffer after that
	 * byte.
	 */
	*buf_p = fp->f_buf + off;
	*size_p = block_size - off;

	/*
	 * But truncate buffer at end of file.
	 */
	if (*size_p > fp->f_di.di_size - fp->f_seekp)
		*size_p = fp->f_di.di_size - fp->f_seekp;

	return (0);
}

/*
 * Search a directory for a name and return its
 * i_number.
 */
static int
search_directory(char *name, struct open_file *f, ufsino_t *inumber_p)
{
	struct file *fp = (struct file *)f->f_fsdata;
	int namlen, length, rc;
	struct direct *dp, *edp;
	size_t buf_size;
	char *buf;

	length = strlen(name);

	fp->f_seekp = 0;
	while ((u_int64_t)fp->f_seekp < fp->f_di.di_size) {
		rc = buf_read_file(f, &buf, &buf_size);
		if (rc)
			return (rc);

		dp = (struct direct *)buf;
		edp = (struct direct *)(buf + buf_size);
		while (dp < edp) {
			if (dp->d_ino == 0)
				goto next;
#if BYTE_ORDER == LITTLE_ENDIAN
			if (fp->f_fs->fs_maxsymlinklen <= 0)
				namlen = dp->d_type;
			else
#endif
				namlen = dp->d_namlen;
			if (namlen == length &&
			    !strcmp(name, dp->d_name)) {
				/* found entry */
				*inumber_p = dp->d_ino;
				return (0);
			}
		next:
			dp = (struct direct *)((char *)dp + dp->d_reclen);
		}
		fp->f_seekp += buf_size;
	}
	return (ENOENT);
}

/*
 * Open a file.
 */
int
ufs_open(char *path, struct open_file *f)
{
	char namebuf[PATH_MAX+1], *cp, *ncp, *buf = NULL;
	ufsino_t inumber, parent_inumber;
	int rc, c, nlinks = 0;
	struct file *fp;
	size_t buf_size;
	struct fs *fs;

	/* allocate file system specific data structure */
	fp = alloc(sizeof(struct file));
	bzero(fp, sizeof(struct file));
	f->f_fsdata = (void *)fp;

	/* allocate space and read super block */
	fs = alloc(SBSIZE);
	fp->f_fs = fs;
	twiddle();
	rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
	    SBLOCK, SBSIZE, (char *)fs, &buf_size);
	if (rc)
		goto out;

	if (buf_size != SBSIZE || fs->fs_magic != FS_MAGIC ||
	    (size_t)fs->fs_bsize > MAXBSIZE ||
	    (size_t)fs->fs_bsize < sizeof(struct fs)) {
		rc = EINVAL;
		goto out;
	}
#ifdef COMPAT_UFS
	ffs_oldfscompat(fs);
#endif

	/*
	 * Calculate indirect block levels.
	 */
	{
		int mult;
		int level;

		mult = 1;
		for (level = 0; level < NIADDR; level++) {
			mult *= NINDIR(fs);
			fp->f_nindir[level] = mult;
		}
	}

	inumber = ROOTINO;
	if ((rc = read_inode(inumber, f)) != 0)
		goto out;

	cp = path;
	while (*cp) {

		/*
		 * Remove extra separators
		 */
		while (*cp == '/')
			cp++;
		if (*cp == '\0')
			break;

		/*
		 * Check that current node is a directory.
		 */
		if ((fp->f_di.di_mode & IFMT) != IFDIR) {
			rc = ENOTDIR;
			goto out;
		}

		/*
		 * Get next component of path name.
		 */
		{
			int len = 0;

			ncp = cp;
			while ((c = *cp) != '\0' && c != '/') {
				if (++len > MAXNAMLEN) {
					rc = ENOENT;
					goto out;
				}
				cp++;
			}
			*cp = '\0';
		}

		/*
		 * Look up component in current directory.
		 * Save directory inumber in case we find a
		 * symbolic link.
		 */
		parent_inumber = inumber;
		rc = search_directory(ncp, f, &inumber);
		*cp = c;
		if (rc)
			goto out;

		/*
		 * Open next component.
		 */
		if ((rc = read_inode(inumber, f)) != 0)
			goto out;

		/*
		 * Check for symbolic link.
		 */
		if ((fp->f_di.di_mode & IFMT) == IFLNK) {
			u_int64_t link_len = fp->f_di.di_size;
			size_t len;

			len = strlen(cp);

			if (link_len + len > PATH_MAX ||
			    ++nlinks > SYMLOOP_MAX) {
				rc = ENOENT;
				goto out;
			}

			bcopy(cp, &namebuf[link_len], len + 1);

			if (link_len < (u_int64_t)fs->fs_maxsymlinklen) {
				bcopy(fp->f_di.di_shortlink, namebuf, link_len);
			} else {
				/*
				 * Read file for symbolic link
				 */
				daddr32_t disk_block;
				fs = fp->f_fs;

				if (!buf)
					buf = alloc(fs->fs_bsize);
				rc = block_map(f, (daddr32_t)0, &disk_block);
				if (rc)
					goto out;

				twiddle();
				rc = (f->f_dev->dv_strategy)(f->f_devdata,
				    F_READ, fsbtodb(fs, disk_block),
				    fs->fs_bsize, buf, &buf_size);
				if (rc)
					goto out;

				bcopy(buf, namebuf, link_len);
			}

			/*
			 * If relative pathname, restart at parent directory.
			 * If absolute pathname, restart at root.
			 */
			cp = namebuf;
			if (*cp != '/')
				inumber = parent_inumber;
			else
				inumber = ROOTINO;

			if ((rc = read_inode(inumber, f)) != 0)
				goto out;
		}
	}

	/*
	 * Found terminal component.
	 */
	rc = 0;
out:
	if (buf)
		free(buf, fs->fs_bsize);
	if (rc)
		(void)ufs_close_internal(fp);

	return (rc);
}

int
ufs_close(struct open_file *f)
{
	struct file *fp = (struct file *)f->f_fsdata;

	f->f_fsdata = NULL;
	if (fp == NULL)
		return (0);

	return (ufs_close_internal(fp));
}

static int
ufs_close_internal(struct file *fp)
{
	int level;

	for (level = 0; level < NIADDR; level++) {
		if (fp->f_blk[level])
			free(fp->f_blk[level], fp->f_fs->fs_bsize);
	}
	if (fp->f_buf)
		free(fp->f_buf, fp->f_fs->fs_bsize);
	free(fp->f_fs, SBSIZE);
	free(fp, sizeof(struct file));
	return (0);
}

/*
 * Copy a portion of a file into kernel memory.
 * Cross block boundaries when necessary.
 */
int
ufs_read(struct open_file *f, void *start, size_t size, size_t *resid)
{
	struct file *fp = (struct file *)f->f_fsdata;
	char *buf, *addr = start;
	size_t csize, buf_size;
	int rc = 0;

	while (size != 0) {
		if ((u_int64_t)fp->f_seekp >= fp->f_di.di_size)
			break;

		rc = buf_read_file(f, &buf, &buf_size);
		if (rc)
			break;

		csize = size;
		if (csize > buf_size)
			csize = buf_size;

		bcopy(buf, addr, csize);

		fp->f_seekp += csize;
		addr += csize;
		size -= csize;
	}
	if (resid)
		*resid = size;
	return (rc);
}

/*
 * Not implemented.
 */
int
ufs_write(struct open_file *f, void *start, size_t size, size_t *resid)
{

	return (EROFS);
}

off_t
ufs_seek(struct open_file *f, off_t offset, int where)
{
	struct file *fp = (struct file *)f->f_fsdata;

	switch (where) {
	case SEEK_SET:
		fp->f_seekp = offset;
		break;
	case SEEK_CUR:
		fp->f_seekp += offset;
		break;
	case SEEK_END:
		fp->f_seekp = fp->f_di.di_size - offset;
		break;
	default:
		return (-1);
	}
	return (fp->f_seekp);
}

int
ufs_stat(struct open_file *f, struct stat *sb)
{
	struct file *fp = (struct file *)f->f_fsdata;

	/* only important stuff */
	sb->st_mode = fp->f_di.di_mode;
	sb->st_uid = fp->f_di.di_uid;
	sb->st_gid = fp->f_di.di_gid;
	sb->st_size = fp->f_di.di_size;
	return (0);
}

#ifndef	NO_READDIR
int
ufs_readdir(struct open_file *f, char *name)
{
	struct file *fp = (struct file *)f->f_fsdata;
	struct direct *dp, *edp;
	size_t buf_size;
	int rc, namlen;
	char *buf;

	if (name == NULL)
		fp->f_seekp = 0;
	else {
			/* end of dir */
		if ((u_int64_t)fp->f_seekp >= fp->f_di.di_size) {
			*name = '\0';
			return -1;
		}

		do {
			if ((rc = buf_read_file(f, &buf, &buf_size)) != 0)
				return rc;

			dp = (struct direct *)buf;
			edp = (struct direct *)(buf + buf_size);
			while (dp < edp && dp->d_ino == 0)
				dp = (struct direct *)((char *)dp + dp->d_reclen);
			fp->f_seekp += buf_size -
			    ((u_int8_t *)edp - (u_int8_t *)dp);
		} while (dp >= edp);

#if BYTE_ORDER == LITTLE_ENDIAN
		if (fp->f_fs->fs_maxsymlinklen <= 0)
			namlen = dp->d_type;
		else
#endif
			namlen = dp->d_namlen;
		strncpy(name, dp->d_name, namlen + 1);

		fp->f_seekp += dp->d_reclen;
	}

	return 0;
}
#endif

#ifdef COMPAT_UFS
/*
 * Sanity checks for old file systems.
 *
 * XXX - goes away some day.
 */
static void
ffs_oldfscompat(struct fs *fs)
{
	int i;

	fs->fs_npsect = max(fs->fs_npsect, fs->fs_nsect);	/* XXX */
	fs->fs_interleave = max(fs->fs_interleave, 1);		/* XXX */
	if (fs->fs_postblformat == FS_42POSTBLFMT)		/* XXX */
		fs->fs_nrpos = 8;				/* XXX */
	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
		quad_t sizepb = fs->fs_bsize;			/* XXX */
								/* XXX */
		fs->fs_maxfilesize = fs->fs_bsize * NDADDR - 1;	/* XXX */
		for (i = 0; i < NIADDR; i++) {			/* XXX */
			sizepb *= NINDIR(fs);			/* XXX */
			fs->fs_maxfilesize += sizepb;		/* XXX */
		}						/* XXX */
		fs->fs_qbmask = ~fs->fs_bmask;			/* XXX */
		fs->fs_qfmask = ~fs->fs_fmask;			/* XXX */
	}							/* XXX */
}
#endif


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: ufs.c,v 1.5 2017/08/29 21:10:20 deraadt Exp $ */
2			/* $NetBSD: ufs.c,v 1.16 1996/09/30 16:01:22 ws Exp $ */
3
4			/*-
5			* Copyright (c) 1993
6			* The Regents of the University of California. All rights reserved.
7			*
8			* This code is derived from software contributed to Berkeley by
9			* The Mach Operating System project at Carnegie-Mellon University.
10			*
11			* Redistribution and use in source and binary forms, with or without
12			* modification, are permitted provided that the following conditions
13			* are met:
14			* 1. Redistributions of source code must retain the above copyright
15			* notice, this list of conditions and the following disclaimer.
16			* 2. Redistributions in binary form must reproduce the above copyright
17			* notice, this list of conditions and the following disclaimer in the
18			* documentation and/or other materials provided with the distribution.
19			* 3. Neither the name of the University nor the names of its contributors
20			* may be used to endorse or promote products derived from this software
21			* without specific prior written permission.
22			*
23			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33			* SUCH DAMAGE.
34			*
35			*
36			* Copyright (c) 1990, 1991 Carnegie Mellon University
37			* All Rights Reserved.
38			*
39			* Author: David Golub
40			*
41			* Permission to use, copy, modify and distribute this software and its
42			* documentation is hereby granted, provided that both the copyright
43			* notice and this permission notice appear in all copies of the
44			* software, derivative works or modified versions, and any portions
45			* thereof, and that both notices appear in supporting documentation.
46			*
47			* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
48			* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
49			* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
50			*
51			* Carnegie Mellon requests users of this software to return to
52			*
53			* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
54			* School of Computer Science
55			* Carnegie Mellon University
56			* Pittsburgh PA 15213-3890
57			*
58			* any improvements or extensions that they make and grant Carnegie the
59			* rights to redistribute these changes.
60			*/
61
62			/*
63			* Stand-alone file reading package.
64			*/
65
66			#include <sys/param.h> /* DEV_BSIZE MAXBSIZE */
67			#include <sys/time.h>
68			#include <sys/stat.h>
69			#include <ufs/ffs/fs.h>
70			#include <ufs/ufs/dinode.h>
71			#include <ufs/ufs/dir.h>
72
73			#include <limits.h>
74
75			#include "vmboot.h"
76
77			/* Used in the kernel by libsa */
78			#define alloc malloc
79			#define free(_p, _n) free(_p)
80			#define twiddle() do { } while(0)
81			#define NO_READDIR 1
82
83			/*
84			* In-core open file.
85			*/
86			struct file {
87			off_t f_seekp; /* seek pointer */
88			struct fs f_fs; / pointer to super-block */
89			struct ufs1_dinode f_di; /* copy of on-disk inode */
90			int f_nindir[NIADDR];
91			/* number of blocks mapped by
92			indirect block at level i */
93			char f_blk[NIADDR]; / buffer for indirect block at
94			level i */
95			size_t f_blksize[NIADDR];
96			/* size of buffer */
97			daddr32_t f_blkno[NIADDR];/* disk address of block in buffer */
98			char f_buf; / buffer for data block */
99			size_t f_buf_size; /* size of data block */
100			daddr32_t f_buf_blkno; /* block number of data block */
101			};
102
103			static int read_inode(ufsino_t, struct open_file *);
104			static int block_map(struct open_file , daddr32_t, daddr32_t );
105			static int buf_read_file(struct open_file , char , size_t );
106			static int search_directory(char , struct open_file , ufsino_t *);
107			static int ufs_close_internal(struct file *);
108			#ifdef COMPAT_UFS
109			static void ffs_oldfscompat(struct fs *);
110			#endif
111
112			/*
113			* Read a new inode into a file structure.
114			*/
115			static int
116			read_inode(ufsino_t inumber, struct open_file *f)
117			{
118			struct file fp = (struct file )f->f_fsdata;
119			struct fs *fs = fp->f_fs;
120			char *buf;
121			size_t rsize;
122			int rc;
123
124			/*
125			* Read inode and save it.
126			*/
127			buf = alloc(fs->fs_bsize);
128			twiddle();
129			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
130			fsbtodb(fs, (daddr32_t)ino_to_fsba(fs, inumber)), fs->fs_bsize,
131			buf, &rsize);
132			if (rc)
133			goto out;
134			if (rsize != (size_t)fs->fs_bsize) {
135			rc = EIO;
136			goto out;
137			}
138
139			{
140			struct ufs1_dinode *dp;
141
142			dp = (struct ufs1_dinode *)buf;
143			fp->f_di = dp[ino_to_fsbo(fs, inumber)];
144			}
145
146			/*
147			* Clear out the old buffers
148			*/
149			{
150			int level;
151
152			for (level = 0; level < NIADDR; level++)
153			fp->f_blkno[level] = -1;
154			fp->f_buf_blkno = -1;
155			fp->f_seekp = 0;
156			}
157			out:
158			free(buf, fs->fs_bsize);
159			return (rc);
160			}
161
162			/*
163			* Given an offset in a file, find the disk block number that
164			* contains that block.
165			*/
166			static int
167			block_map(struct open_file f, daddr32_t file_block, daddr32_t disk_block_p)
168			{
169			struct file fp = (struct file )f->f_fsdata;
170			daddr32_t ind_block_num, *ind_p;
171			struct fs *fs = fp->f_fs;
172			int level, idx, rc;
173
174			/*
175			* Index structure of an inode:
176			*
177			* di_db[0..NDADDR-1] hold block numbers for blocks
178			* 0..NDADDR-1
179			*
180			* di_ib[0] index block 0 is the single indirect block
181			* holds block numbers for blocks
182			* NDADDR .. NDADDR + NINDIR(fs)-1
183			*
184			* di_ib[1] index block 1 is the double indirect block
185			* holds block numbers for INDEX blocks for blocks
186			* NDADDR + NINDIR(fs) ..
187			* NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
188			*
189			* di_ib[2] index block 2 is the triple indirect block
190			* holds block numbers for double-indirect
191			* blocks for blocks
192			* NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
193			* NDADDR + NINDIR(fs) + NINDIR(fs)**2
194			* + NINDIR(fs)**3 - 1
195			*/
196
197			if (file_block < NDADDR) {
198			/* Direct block. */
199			*disk_block_p = fp->f_di.di_db[file_block];
200			return (0);
201			}
202
203			file_block -= NDADDR;
204
205			/*
206			* nindir[0] = NINDIR
207			* nindir[1] = NINDIR**2
208			* nindir[2] = NINDIR**3
209			* etc
210			*/
211			for (level = 0; level < NIADDR; level++) {
212			if (file_block < fp->f_nindir[level])
213			break;
214			file_block -= fp->f_nindir[level];
215			}
216			if (level == NIADDR) {
217			/* Block number too high */
218			return (EFBIG);
219			}
220
221			ind_block_num = fp->f_di.di_ib[level];
222
223			for (; level >= 0; level--) {
224			if (ind_block_num == 0) {
225			disk_block_p = 0; / missing */
226			return (0);
227			}
228
229			if (fp->f_blkno[level] != ind_block_num) {
230			if (fp->f_blk[level] == NULL)
231			fp->f_blk[level] =
232			alloc(fs->fs_bsize);
233			twiddle();
234			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
235			fsbtodb(fp->f_fs, ind_block_num), fs->fs_bsize,
236			fp->f_blk[level], &fp->f_blksize[level]);
237			if (rc)
238			return (rc);
239			if (fp->f_blksize[level] != (size_t)fs->fs_bsize)
240			return (EIO);
241			fp->f_blkno[level] = ind_block_num;
242			}
243
244			ind_p = (daddr32_t *)fp->f_blk[level];
245
246			if (level > 0) {
247			idx = file_block / fp->f_nindir[level - 1];
248			file_block %= fp->f_nindir[level - 1];
249			} else
250			idx = file_block;
251
252			ind_block_num = ind_p[idx];
253			}
254
255			*disk_block_p = ind_block_num;
256			return (0);
257			}
258
259			/*
260			* Read a portion of a file into an internal buffer. Return
261			* the location in the buffer and the amount in the buffer.
262			*/
263			static int
264			buf_read_file(struct open_file f, char buf_p, size_t size_p)
265			{
266			struct file fp = (struct file )f->f_fsdata;
267			struct fs *fs = fp->f_fs;
268			daddr32_t file_block, disk_block;
269			size_t block_size;
270			long off;
271			int rc;
272
273			off = blkoff(fs, fp->f_seekp);
274			file_block = lblkno(fs, fp->f_seekp);
275			block_size = dblksize(fs, &fp->f_di, (u_int64_t)file_block);
276
277			if (file_block != fp->f_buf_blkno) {
278			rc = block_map(f, file_block, &disk_block);
279			if (rc)
280			return (rc);
281
282			if (fp->f_buf == NULL)
283			fp->f_buf = alloc(fs->fs_bsize);
284
285			if (disk_block == 0) {
286			bzero(fp->f_buf, block_size);
287			fp->f_buf_size = block_size;
288			} else {
289			twiddle();
290			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
291			fsbtodb(fs, disk_block),
292			block_size, fp->f_buf, &fp->f_buf_size);
293			if (rc)
294			return (rc);
295			}
296
297			fp->f_buf_blkno = file_block;
298			}
299
300			/*
301			* Return address of byte in buffer corresponding to
302			* offset, and size of remainder of buffer after that
303			* byte.
304			*/
305			*buf_p = fp->f_buf + off;
306			*size_p = block_size - off;
307
308			/*
309			* But truncate buffer at end of file.
310			*/
311			if (*size_p > fp->f_di.di_size - fp->f_seekp)
312			*size_p = fp->f_di.di_size - fp->f_seekp;
313
314			return (0);
315			}
316
317			/*
318			* Search a directory for a name and return its
319			* i_number.
320			*/
321			static int
322			search_directory(char name, struct open_file f, ufsino_t *inumber_p)
323			{
324			struct file fp = (struct file )f->f_fsdata;
325			int namlen, length, rc;
326			struct direct dp, edp;
327			size_t buf_size;
328			char *buf;
329
330			length = strlen(name);
331
332			fp->f_seekp = 0;
333			while ((u_int64_t)fp->f_seekp < fp->f_di.di_size) {
334			rc = buf_read_file(f, &buf, &buf_size);
335			if (rc)
336			return (rc);
337
338			dp = (struct direct *)buf;
339			edp = (struct direct *)(buf + buf_size);
340			while (dp < edp) {
341			if (dp->d_ino == 0)
342			goto next;
343			#if BYTE_ORDER == LITTLE_ENDIAN
344			if (fp->f_fs->fs_maxsymlinklen <= 0)
345			namlen = dp->d_type;
346			else
347			#endif
348			namlen = dp->d_namlen;
349			if (namlen == length &&
350			!strcmp(name, dp->d_name)) {
351			/* found entry */
352			*inumber_p = dp->d_ino;
353			return (0);
354			}
355			next:
356			dp = (struct direct )((char )dp + dp->d_reclen);
357			}
358			fp->f_seekp += buf_size;
359			}
360			return (ENOENT);
361			}
362
363			/*
364			* Open a file.
365			*/
366			int
367			ufs_open(char path, struct open_file f)
368			{
369			char namebuf[PATH_MAX+1], cp, ncp, *buf = NULL;
370			ufsino_t inumber, parent_inumber;
371			int rc, c, nlinks = 0;
372			struct file *fp;
373			size_t buf_size;
374			struct fs *fs;
375
376			/* allocate file system specific data structure */
377			fp = alloc(sizeof(struct file));
378			bzero(fp, sizeof(struct file));
379			f->f_fsdata = (void *)fp;
380
381			/* allocate space and read super block */
382			fs = alloc(SBSIZE);
383			fp->f_fs = fs;
384			twiddle();
385			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
386			SBLOCK, SBSIZE, (char *)fs, &buf_size);
387			if (rc)
388			goto out;
389
390			if (buf_size != SBSIZE \|\| fs->fs_magic != FS_MAGIC \|\|
391			(size_t)fs->fs_bsize > MAXBSIZE \|\|
392			(size_t)fs->fs_bsize < sizeof(struct fs)) {
393			rc = EINVAL;
394			goto out;
395			}
396			#ifdef COMPAT_UFS
397			ffs_oldfscompat(fs);
398			#endif
399
400			/*
401			* Calculate indirect block levels.
402			*/
403			{
404			int mult;
405			int level;
406
407			mult = 1;
408			for (level = 0; level < NIADDR; level++) {
409			mult *= NINDIR(fs);
410			fp->f_nindir[level] = mult;
411			}
412			}
413
414			inumber = ROOTINO;
415			if ((rc = read_inode(inumber, f)) != 0)
416			goto out;
417
418			cp = path;
419			while (*cp) {
420
421			/*
422			* Remove extra separators
423			*/
424			while (*cp == '/')
425			cp++;
426			if (*cp == '\0')
427			break;
428
429			/*
430			* Check that current node is a directory.
431			*/
432			if ((fp->f_di.di_mode & IFMT) != IFDIR) {
433			rc = ENOTDIR;
434			goto out;
435			}
436
437			/*
438			* Get next component of path name.
439			*/
440			{
441			int len = 0;
442
443			ncp = cp;
444			while ((c = *cp) != '\0' && c != '/') {
445			if (++len > MAXNAMLEN) {
446			rc = ENOENT;
447			goto out;
448			}
449			cp++;
450			}
451			*cp = '\0';
452			}
453
454			/*
455			* Look up component in current directory.
456			* Save directory inumber in case we find a
457			* symbolic link.
458			*/
459			parent_inumber = inumber;
460			rc = search_directory(ncp, f, &inumber);
461			*cp = c;
462			if (rc)
463			goto out;
464
465			/*
466			* Open next component.
467			*/
468			if ((rc = read_inode(inumber, f)) != 0)
469			goto out;
470
471			/*
472			* Check for symbolic link.
473			*/
474			if ((fp->f_di.di_mode & IFMT) == IFLNK) {
475			u_int64_t link_len = fp->f_di.di_size;
476			size_t len;
477
478			len = strlen(cp);
479
480			if (link_len + len > PATH_MAX \|\|
481			++nlinks > SYMLOOP_MAX) {
482			rc = ENOENT;
483			goto out;
484			}
485
486			bcopy(cp, &namebuf[link_len], len + 1);
487
488			if (link_len < (u_int64_t)fs->fs_maxsymlinklen) {
489			bcopy(fp->f_di.di_shortlink, namebuf, link_len);
490			} else {
491			/*
492			* Read file for symbolic link
493			*/
494			daddr32_t disk_block;
495			fs = fp->f_fs;
496
497			if (!buf)
498			buf = alloc(fs->fs_bsize);
499			rc = block_map(f, (daddr32_t)0, &disk_block);
500			if (rc)
501			goto out;
502
503			twiddle();
504			rc = (f->f_dev->dv_strategy)(f->f_devdata,
505			F_READ, fsbtodb(fs, disk_block),
506			fs->fs_bsize, buf, &buf_size);
507			if (rc)
508			goto out;
509
510			bcopy(buf, namebuf, link_len);
511			}
512
513			/*
514			* If relative pathname, restart at parent directory.
515			* If absolute pathname, restart at root.
516			*/
517			cp = namebuf;
518			if (*cp != '/')
519			inumber = parent_inumber;
520			else
521			inumber = ROOTINO;
522
523			if ((rc = read_inode(inumber, f)) != 0)
524			goto out;
525			}
526			}
527
528			/*
529			* Found terminal component.
530			*/
531			rc = 0;
532			out:
533			if (buf)
534			free(buf, fs->fs_bsize);
535			if (rc)
536			(void)ufs_close_internal(fp);
537
538			return (rc);
539			}
540
541			int
542			ufs_close(struct open_file *f)
543			{
544			struct file fp = (struct file )f->f_fsdata;
545
546			f->f_fsdata = NULL;
547			if (fp == NULL)
548			return (0);
549
550			return (ufs_close_internal(fp));
551			}
552
553			static int
554			ufs_close_internal(struct file *fp)
555			{
556			int level;
557
558			for (level = 0; level < NIADDR; level++) {
559			if (fp->f_blk[level])
560			free(fp->f_blk[level], fp->f_fs->fs_bsize);
561			}
562			if (fp->f_buf)
563			free(fp->f_buf, fp->f_fs->fs_bsize);
564			free(fp->f_fs, SBSIZE);
565			free(fp, sizeof(struct file));
566			return (0);
567			}
568
569			/*
570			* Copy a portion of a file into kernel memory.
571			* Cross block boundaries when necessary.
572			*/
573			int
574			ufs_read(struct open_file f, void start, size_t size, size_t *resid)
575			{
576			struct file fp = (struct file )f->f_fsdata;
577			char buf, addr = start;
578			size_t csize, buf_size;
579			int rc = 0;
580
581			while (size != 0) {
582			if ((u_int64_t)fp->f_seekp >= fp->f_di.di_size)
583			break;
584
585			rc = buf_read_file(f, &buf, &buf_size);
586			if (rc)
587			break;
588
589			csize = size;
590			if (csize > buf_size)
591			csize = buf_size;
592
593			bcopy(buf, addr, csize);
594
595			fp->f_seekp += csize;
596			addr += csize;
597			size -= csize;
598			}
599			if (resid)
600			*resid = size;
601			return (rc);
602			}
603
604			/*
605			* Not implemented.
606			*/
607			int
608			ufs_write(struct open_file f, void start, size_t size, size_t *resid)
609			{
610
611			return (EROFS);
612			}
613
614			off_t
615			ufs_seek(struct open_file *f, off_t offset, int where)
616			{
617			struct file fp = (struct file )f->f_fsdata;
618
619			switch (where) {
620			case SEEK_SET:
621			fp->f_seekp = offset;
622			break;
623			case SEEK_CUR:
624			fp->f_seekp += offset;
625			break;
626			case SEEK_END:
627			fp->f_seekp = fp->f_di.di_size - offset;
628			break;
629			default:
630			return (-1);
631			}
632			return (fp->f_seekp);
633			}
634
635			int
636			ufs_stat(struct open_file f, struct stat sb)
637			{
638			struct file fp = (struct file )f->f_fsdata;
639
640			/* only important stuff */
641			sb->st_mode = fp->f_di.di_mode;
642			sb->st_uid = fp->f_di.di_uid;
643			sb->st_gid = fp->f_di.di_gid;
644			sb->st_size = fp->f_di.di_size;
645			return (0);
646			}
647
648			#ifndef NO_READDIR
649			int
650			ufs_readdir(struct open_file f, char name)
651			{
652			struct file fp = (struct file )f->f_fsdata;
653			struct direct dp, edp;
654			size_t buf_size;
655			int rc, namlen;
656			char *buf;
657
658			if (name == NULL)
659			fp->f_seekp = 0;
660			else {
661			/* end of dir */
662			if ((u_int64_t)fp->f_seekp >= fp->f_di.di_size) {
663			*name = '\0';
664			return -1;
665			}
666
667			do {
668			if ((rc = buf_read_file(f, &buf, &buf_size)) != 0)
669			return rc;
670
671			dp = (struct direct *)buf;
672			edp = (struct direct *)(buf + buf_size);
673			while (dp < edp && dp->d_ino == 0)
674			dp = (struct direct )((char )dp + dp->d_reclen);
675			fp->f_seekp += buf_size -
676			((u_int8_t )edp - (u_int8_t )dp);
677			} while (dp >= edp);
678
679			#if BYTE_ORDER == LITTLE_ENDIAN
680			if (fp->f_fs->fs_maxsymlinklen <= 0)
681			namlen = dp->d_type;
682			else
683			#endif
684			namlen = dp->d_namlen;
685			strncpy(name, dp->d_name, namlen + 1);
686
687			fp->f_seekp += dp->d_reclen;
688			}
689
690			return 0;
691			}
692			#endif
693
694			#ifdef COMPAT_UFS
695			/*
696			* Sanity checks for old file systems.
697			*
698			* XXX - goes away some day.
699			*/
700			static void
701			ffs_oldfscompat(struct fs *fs)
702			{
703			int i;
704
705			fs->fs_npsect = max(fs->fs_npsect, fs->fs_nsect); /* XXX */
706			fs->fs_interleave = max(fs->fs_interleave, 1); /* XXX */
707			if (fs->fs_postblformat == FS_42POSTBLFMT) /* XXX */
708			fs->fs_nrpos = 8; /* XXX */
709			if (fs->fs_inodefmt < FS_44INODEFMT) { /* XXX */
710			quad_t sizepb = fs->fs_bsize; /* XXX */
711			/* XXX */
712			fs->fs_maxfilesize = fs->fs_bsize * NDADDR - 1; /* XXX */
713			for (i = 0; i < NIADDR; i++) { /* XXX */
714			sizepb = NINDIR(fs); / XXX */
715			fs->fs_maxfilesize += sizepb; /* XXX */
716			} /* XXX */
717			fs->fs_qbmask = ~fs->fs_bmask; /* XXX */
718			fs->fs_qfmask = ~fs->fs_fmask; /* XXX */
719			} /* XXX */
720			}
721			#endif