From 8a0cdef1619ead670a2cba876a3cb97e41aa5e83 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 16 Apr 2018 18:46:26 +0200 Subject: udf: Add support for decoding UTF-16 characters Add support to decode characters outside of Base Multilingual Plane of UTF-16 encoded in CS0 charset of UDF. Signed-off-by: Jan Kara --- fs/udf/unicode.c | 103 ++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 68 insertions(+), 35 deletions(-) (limited to 'fs/udf') diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c index 616ffee441c5..45234791fec2 100644 --- a/fs/udf/unicode.c +++ b/fs/udf/unicode.c @@ -36,25 +36,6 @@ #define SURROGATE_CHAR_BITS 10 #define SURROGATE_CHAR_MASK ((1 << SURROGATE_CHAR_BITS) - 1) -static int udf_uni2char_utf8(wchar_t uni, - unsigned char *out, - int boundlen) -{ - int u_len = 0; - - if (boundlen <= 0) - return -ENAMETOOLONG; - - u_len = utf32_to_utf8(uni, out, boundlen); - if (u_len < 0) { - if (uni > UNICODE_MAX || - (uni & SURROGATE_MASK) == SURROGATE_PAIR) - return -EINVAL; - return -ENAMETOOLONG; - } - return u_len; -} - #define ILLEGAL_CHAR_MARK '_' #define EXT_MARK '.' #define CRC_MARK '#' @@ -62,6 +43,50 @@ static int udf_uni2char_utf8(wchar_t uni, /* Number of chars we need to store generated CRC to make filename unique */ #define CRC_LEN 5 +static unicode_t get_utf16_char(const uint8_t *str_i, int str_i_max_len, + int str_i_idx, int u_ch, unicode_t *ret) +{ + unicode_t c; + int start_idx = str_i_idx; + + /* Expand OSTA compressed Unicode to Unicode */ + c = str_i[str_i_idx++]; + if (u_ch > 1) + c = (c << 8) | str_i[str_i_idx++]; + if ((c & SURROGATE_MASK) == SURROGATE_PAIR) { + unicode_t next; + + /* Trailing surrogate char */ + if (str_i_idx >= str_i_max_len) { + c = UNICODE_MAX + 1; + goto out; + } + + /* Low surrogate must follow the high one... */ + if (c & SURROGATE_LOW) { + c = UNICODE_MAX + 1; + goto out; + } + + WARN_ON_ONCE(u_ch != 2); + next = str_i[str_i_idx++] << 8; + next |= str_i[str_i_idx++]; + if ((next & SURROGATE_MASK) != SURROGATE_PAIR || + !(next & SURROGATE_LOW)) { + c = UNICODE_MAX + 1; + goto out; + } + + c = PLANE_SIZE + + ((c & SURROGATE_CHAR_MASK) << SURROGATE_CHAR_BITS) + + (next & SURROGATE_CHAR_MASK); + } +out: + *ret = c; + return str_i_idx - start_idx; +} + + static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len, int *str_o_idx, const uint8_t *str_i, int str_i_max_len, @@ -70,27 +95,29 @@ static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len, int (*conv_f)(wchar_t, unsigned char *, int), int translate) { - uint32_t c; + unicode_t c; int illChar = 0; int len, gotch = 0; - for (; (!gotch) && (*str_i_idx < str_i_max_len); *str_i_idx += u_ch) { + while (!gotch && *str_i_idx < str_i_max_len) { if (*str_o_idx >= str_o_max_len) { *needsCRC = 1; return gotch; } - /* Expand OSTA compressed Unicode to Unicode */ - c = str_i[*str_i_idx]; - if (u_ch > 1) - c = (c << 8) | str_i[*str_i_idx + 1]; - - if (translate && (c == '/' || c == 0)) + len = get_utf16_char(str_i, str_i_max_len, *str_i_idx, u_ch, + &c); + /* These chars cannot be converted. Replace them. */ + if (c == 0 || c > UNICODE_MAX || (conv_f && c > MAX_WCHAR_T) || + (translate && c == '/')) { illChar = 1; - else if (illChar) + if (!translate) + gotch = 1; + } else if (illChar) break; else gotch = 1; + *str_i_idx += len; } if (illChar) { *needsCRC = 1; @@ -98,7 +125,15 @@ static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len, gotch = 1; } if (gotch) { - len = conv_f(c, &str_o[*str_o_idx], str_o_max_len - *str_o_idx); + if (conv_f) { + len = conv_f(c, &str_o[*str_o_idx], + str_o_max_len - *str_o_idx); + } else { + len = utf32_to_utf8(c, &str_o[*str_o_idx], + str_o_max_len - *str_o_idx); + if (len < 0) + len = -ENAMETOOLONG; + } /* Valid character? */ if (len >= 0) *str_o_idx += len; @@ -106,7 +141,7 @@ static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len, *needsCRC = 1; gotch = 0; } else { - str_o[(*str_o_idx)++] = '?'; + str_o[(*str_o_idx)++] = ILLEGAL_CHAR_MARK; *needsCRC = 1; } } @@ -142,12 +177,10 @@ static int udf_name_from_CS0(struct super_block *sb, return 0; } - if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) { - conv_f = udf_uni2char_utf8; - } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) { + if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) conv_f = UDF_SB(sb)->s_nls_map->uni2char; - } else - BUG(); + else + conv_f = NULL; cmp_id = ocu[0]; if (cmp_id != 8 && cmp_id != 16) { -- cgit