- 根目录:
- fs
- udf
- unicode.c
/*
* unicode.c
*
* PURPOSE
* Routines for converting between UTF-8 and OSTA Compressed Unicode.
* Also handles filename mangling
*
* DESCRIPTION
* OSTA Compressed Unicode is explained in the OSTA UDF specification.
* http://www.osta.org/
* UTF-8 is explained in the IETF RFC XXXX.
* ftp://ftp.internic.net/rfc/rfcxxxx.txt
*
* COPYRIGHT
* This file is distributed under the terms of the GNU General Public
* License (GPL). Copies of the GPL can be obtained from:
* ftp://prep.ai.mit.edu/pub/gnu/GPL
* Each contributing author retains all rights to their own work.
*/
#include "udfdecl.h"
#include <linux/kernel.h>
#include <linux/string.h> /* for memset */
#include <linux/nls.h>
#include <linux/crc-itu-t.h>
#include <linux/slab.h>
#include "udf_sb.h"
static int udf_translate_to_linux(uint8_t *, uint8_t *, int, uint8_t *, int);
static int udf_char_to_ustr(struct ustr *dest, const uint8_t *src, int strlen)
{
if ((!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN - 2))
return 0;
memset(dest, 0, sizeof(struct ustr));
memcpy(dest->u_name, src, strlen);
dest->u_cmpID = 0x08;
dest->u_len = strlen;
return strlen;
}
/*
* udf_build_ustr
*/
int udf_build_ustr(struct ustr *dest, dstring *ptr, int size)
{
int usesize;
if (!dest || !ptr || !size)
return -1;
BUG_ON(size < 2);
usesize = min_t(size_t, ptr[size - 1], sizeof(dest->u_name));
usesize = min(usesize, size - 2);
dest->u_cmpID = ptr[0];
dest->u_len = usesize;
memcpy(dest->u_name, ptr + 1, usesize);
memset(dest->u_name + usesize, 0, sizeof(dest->u_name) - usesize);
return 0;
}
/*
* udf_build_ustr_exact
*/
static int udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
{
if ((!dest) || (!ptr) || (!exactsize))
return -1;
memset(dest, 0, sizeof(struct ustr));
dest->u_cmpID = ptr[0];
dest->u_len = exactsize - 1;
memcpy(dest->u_name, ptr + 1, exactsize - 1);
return 0;
}
/*
* udf_ocu_to_utf8
*
* PURPOSE
* Convert OSTA Compressed Unicode to the UTF-8 equivalent.
*
* PRE-CONDITIONS
* utf Pointer to UTF-8 output buffer.
* ocu Pointer to OSTA Compressed Unicode input buffer
* of size UDF_NAME_LEN bytes.
* both of type "struct ustr *"
*
* POST-CONDITIONS
* <return> Zero on success.
*
* HISTORY
* November 12, 1997 - Andrew E. Mileski
* Written, tested, and released.
*/
int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
{
const uint8_t *ocu;
uint8_t cmp_id, ocu_len;
int i;
ocu_len = ocu_i->u_len;
if (ocu_len == 0) {
memset(utf_o, 0, sizeof(struct ustr));
return 0;
}
cmp_id = ocu_i->u_cmpID;
if (cmp_id != 8 && cmp_id != 16) {
memset(utf_o, 0, sizeof(struct ustr));
pr_err("unknown compression code (%d) stri=%s\n",
cmp_id, ocu_i->u_name);
return 0;
}
ocu = ocu_i->u_name;
utf_o->u_len = 0;
for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) {
/* Expand OSTA compressed Unicode to Unicode */
uint32_t c = ocu[i++];
if (cmp_id == 16)
c = (c << 8) | ocu[i++];
/* Compress Unicode to UTF-8 */
if (c < 0x80U)
utf_o->u_name[utf_o->u_len++] = (uint8_t)c;
else if (c < 0x800U) {
utf_o->u_name[utf_o->u_len++] =
(uint8_t)(0xc0 | (c >> 6));
utf_o->u_name[utf_o->u_len++] =
(uint8_t)(0x80 | (c & 0x3f));
} else {
utf_o->u_name[utf_o->u_len++] =
(uint8_t)(0xe0 | (c >> 12));
utf_o->u_name[utf_o->u_len++] =
(uint8_t)(0x80 |
((c >> 6) & 0x3f));
utf_o->u_name[utf_o->u_len++] =
(uint8_t)(0x80 | (c & 0x3f));
}
}
utf_o->u_cmpID = 8;
return utf_o->u_len;
}
/*
*
* udf_utf8_to_ocu
*
* PURPOSE
* Convert UTF-8 to the OSTA Compressed Unicode equivalent.
*
* DESCRIPTION
* This routine is only called by udf_lookup().
*
* PRE-CONDITIONS
* ocu Pointer to OSTA Compressed Unicode output
* buffer of size UDF_NAME_LEN bytes.
* utf Pointer to UTF-8 input buffer.
* utf_len Length of UTF-8 input buffer in bytes.
*
* POST-CONDITIONS
* <return> Zero on success.
*
* HISTORY
* November 12, 1997 - Andrew E. Mileski
* Written, tested, and released.
*/
static int udf_UTF8toCS0(dstring *ocu, struct ustr *utf, int length)
{
unsigned c, i, max_val, utf_char;
int utf_cnt, u_len;
memset(ocu, 0, sizeof(dstring) * length);
ocu[0] = 8;
max_val = 0xffU;
try_again:
u_len = 0U;
utf_char = 0U;
utf_cnt = 0U;
for (i = 0U; i < utf->u_len; i++) {
c = (uint8_t)utf->u_name[i];
/* Complete a multi-byte UTF-8 character */
if (utf_cnt) {
utf_char = (utf_char << 6) | (c & 0x3fU);
if (--utf_cnt)
continue;
} else {
/* Check for a multi-byte UTF-8 character */
if (c & 0x80U) {
/* Start a multi-byte UTF-8 character */
if ((c & 0xe0U) == 0xc0U) {
utf_char = c & 0x1fU;
utf_cnt = 1;
} else if ((c & 0xf0U) == 0xe0U) {
utf_char = c & 0x0fU;
utf_cnt = 2;
} else if ((c & 0xf8U) == 0xf0U) {
utf_char = c & 0x07U;
utf_cnt = 3;
} else if ((c & 0xfcU) == 0xf8U) {
utf_char = c & 0x03U;
utf_cnt = 4;
} else if ((c & 0xfeU) == 0xfcU) {
utf_char = c & 0x01U;
utf_cnt = 5;
} else {
goto error_out;
}
continue;
} else {
/* Single byte UTF-8 character (most common) */
utf_char = c;
}
}
/* Choose no compression if necessary */
if (utf_char > max_val) {
if (max_val == 0xffU) {
max_val = 0xffffU;
ocu[0] = (uint8_t)0x10U;
goto try_again;
}
goto error_out;
}
if (max_val == 0xffffU)
ocu[++u_len] = (uint8_t)(utf_char >> 8);
ocu[++u_len] = (uint8_t)(utf_char & 0xffU);
}
if (utf_cnt) {
error_out:
ocu[++u_len] = '?';
printk(KERN_DEBUG pr_fmt("bad UTF-8 character\n"));
}
ocu[length - 1] = (uint8_t)u_len + 1;
return u_len + 1;
}
static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o,
const struct ustr *ocu_i)
{
const uint8_t *ocu;
uint8_t cmp_id, ocu_len;
int i, len;
ocu_len = ocu_i->u_len;
if (ocu_len == 0) {
memset(utf_o, 0, sizeof(struct ustr));
return 0;
}
cmp_id = ocu_i->u_cmpID;
if (cmp_id != 8 && cmp_id != 16) {
memset(utf_o, 0, sizeof(struct ustr));
pr_err("unknown compression code (%d) stri=%s\n",
cmp_id, ocu_i->u_name);
return 0;
}
ocu = ocu_i->u_name;
utf_o->u_len = 0;
for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) {
/* Expand OSTA compressed Unicode to Unicode */
uint32_t c = ocu[i++];
if (cmp_id == 16)
c = (c << 8) | ocu[i++];
len = nls->uni2char(c, &utf_o->u_name[utf_o->u_len],
UDF_NAME_LEN - utf_o->u_len);
/* Valid character? */
if (len >= 0)
utf_o->u_len += len;
else
utf_o->u_name[utf_o->u_len++] = '?';
}
utf_o->u_cmpID = 8;
return utf_o->u_len;
}
static int udf_NLStoCS0(struct nls_table *nls, dstring *ocu, struct ustr *uni,
int length)
{
int len;
unsigned i, max_val;
uint16_t uni_char;
int u_len;
memset(ocu, 0, sizeof(dstring) * length);
ocu[0] = 8;
max_val = 0xffU;
try_again:
u_len = 0U;
for (i = 0U; i < uni->u_len; i++) {
len = nls->char2uni(&uni->u_name[i], uni->u_len - i, &uni_char);
if (!len)
continue;
/* Invalid character, deal with it */
if (len < 0) {
len = 1;
uni_char = '?';
}
if (uni_char > max_val) {
max_val = 0xffffU;
ocu[0] = (uint8_t)0x10U;
goto try_again;
}
if (max_val == 0xffffU)
ocu[++u_len] = (uint8_t)(uni_char >> 8);
ocu[++u_len] = (uint8_t)(uni_char & 0xffU);
i += len - 1;
}
ocu[length - 1] = (uint8_t)u_len + 1;
return u_len + 1;
}
int udf_get_filename(struct super_block *sb, uint8_t *sname, uint8_t *dname,
int flen)
{
struct ustr *filename, *unifilename;
int len = 0;
filename = kmalloc(sizeof(struct ustr), GFP_NOFS);
if (!filename)
return 0;
unifilename = kmalloc(sizeof(struct ustr), GFP_NOFS);
if (!unifilename)
goto out1;
if (udf_build_ustr_exact(unifilename, sname, flen))
goto out2;
if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
if (!udf_CS0toUTF8(filename, unifilename)) {
udf_debug("Failed in udf_get_filename: sname = %s\n",
sname);
goto out2;
}
} else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
if (!udf_CS0toNLS(UDF_SB(sb)->s_nls_map, filename,
unifilename)) {
udf_debug("Failed in udf_get_filename: sname = %s\n",
sname);
goto out2;
}
} else
goto out2;
len = udf_translate_to_linux(dname, filename->u_name, filename->u_len,
unifilename->u_name, unifilename->u_len);
out2:
kfree(unifilename);
out1:
kfree(filename);
return len;
}
int udf_put_filename(struct super_block *sb, const uint8_t *sname,
uint8_t *dname, int flen)
{
struct ustr unifilename;
int namelen;
if (!udf_char_to_ustr(&unifilename, sname, flen))
return 0;
if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
namelen = udf_UTF8toCS0(dname, &unifilename, UDF_NAME_LEN);
if (!namelen)
return 0;
} else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
namelen = udf_NLStoCS0(UDF_SB(sb)->s_nls_map, dname,
&unifilename, UDF_NAME_LEN);
if (!namelen)
return 0;
} else
return 0;
return namelen;
}
#define ILLEGAL_CHAR_MARK '_'
#define EXT_MARK '.'
#define CRC_MARK '#'
#define EXT_SIZE 5
static int udf_translate_to_linux(uint8_t *newName, uint8_t *udfName,
int udfLen, uint8_t *fidName,
int fidNameLen)
{
int index, newIndex = 0, needsCRC = 0;
int extIndex = 0, newExtIndex = 0, hasExt = 0;
unsigned short valueCRC;
uint8_t curr;
const uint8_t hexChar[] = "0123456789ABCDEF";
if (udfName[0] == '.' &&
(udfLen == 1 || (udfLen == 2 && udfName[1] == '.'))) {
needsCRC = 1;
newIndex = udfLen;
memcpy(newName, udfName, udfLen);
} else {
for (index = 0; index < udfLen; index++) {
curr = udfName[index];
if (curr == '/' || curr == 0) {
needsCRC = 1;
curr = ILLEGAL_CHAR_MARK;
while (index + 1 < udfLen &&
(udfName[index + 1] == '/' ||
udfName[index + 1] == 0))
index++;
}
if (curr == EXT_MARK &&
(udfLen - index - 1) <= EXT_SIZE) {
if (udfLen == index + 1)
hasExt = 0;
else {
hasExt = 1;
extIndex = index;
newExtIndex = newIndex;
}
}
if (newIndex < 256)
newName[newIndex++] = curr;
else
needsCRC = 1;
}
}
if (needsCRC) {
uint8_t ext[EXT_SIZE];
int localExtIndex = 0;
if (hasExt) {
int maxFilenameLen;
for (index = 0;
index < EXT_SIZE && extIndex + index + 1 < udfLen;
index++) {
curr = udfName[extIndex + index + 1];
if (curr == '/' || curr == 0) {
needsCRC = 1;
curr = ILLEGAL_CHAR_MARK;
while (extIndex + index + 2 < udfLen &&
(index + 1 < EXT_SIZE &&
(udfName[extIndex + index + 2] == '/' ||
udfName[extIndex + index + 2] == 0)))
index++;
}
ext[localExtIndex++] = curr;
}
maxFilenameLen = 250 - localExtIndex;
if (newIndex > maxFilenameLen)
newIndex = maxFilenameLen;
else
newIndex = newExtIndex;
} else if (newIndex > 250)
newIndex = 250;
newName[newIndex++] = CRC_MARK;
valueCRC = crc_itu_t(0, fidName, fidNameLen);
newName[newIndex++] = hexChar[(valueCRC & 0xf000) >> 12];
newName[newIndex++] = hexChar[(valueCRC & 0x0f00) >> 8];
newName[newIndex++] = hexChar[(valueCRC & 0x00f0) >> 4];
newName[newIndex++] = hexChar[(valueCRC & 0x000f)];
if (hasExt) {
newName[newIndex++] = EXT_MARK;
for (index = 0; index < localExtIndex; index++)
newName[newIndex++] = ext[index];
}
}
return newIndex;
}