1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * EFI Unicode collation protocol
4 *
5 * Copyright (c) 2018 Heinrich Schuchardt <xypron.glpk@gmx.de>
6 */
7
8 #include <common.h>
9 #include <charset.h>
10 #include <cp1250.h>
11 #include <cp437.h>
12 #include <efi_loader.h>
13
14 /* Characters that may not be used in FAT 8.3 file names */
15 static const char illegal[] = "+,<=>:;\"/\\|?*[]\x7f";
16
17 /*
18 * EDK2 assumes codepage 1250 when creating FAT 8.3 file names.
19 * Linux defaults to codepage 437 for FAT 8.3 file names.
20 */
21 #if CONFIG_FAT_DEFAULT_CODEPAGE == 1250
22 /* Unicode code points for code page 1250 characters 0x80 - 0xff */
23 static const u16 codepage[] = CP1250;
24 #else
25 /* Unicode code points for code page 437 characters 0x80 - 0xff */
26 static const u16 *codepage = codepage_437;
27 #endif
28
29 /* GUID of the EFI_UNICODE_COLLATION_PROTOCOL2 */
30 const efi_guid_t efi_guid_unicode_collation_protocol2 =
31 EFI_UNICODE_COLLATION_PROTOCOL2_GUID;
32
33 /**
34 * efi_stri_coll() - compare utf-16 strings case-insenitively
35 *
36 * @this: unicode collation protocol instance
37 * @s1: first string
38 * @s2: second string
39 *
40 * This function implements the StriColl() service of the
41 * EFI_UNICODE_COLLATION_PROTOCOL2.
42 *
43 * See the Unified Extensible Firmware Interface (UEFI) specification for
44 * details.
45 *
46 * Return: 0: s1 == s2, > 0: s1 > s2, < 0: s1 < s2
47 */
efi_stri_coll(struct efi_unicode_collation_protocol * this,u16 * s1,u16 * s2)48 static efi_intn_t EFIAPI efi_stri_coll(
49 struct efi_unicode_collation_protocol *this, u16 *s1, u16 *s2)
50 {
51 s32 c1, c2;
52 efi_intn_t ret = 0;
53
54 EFI_ENTRY("%p, %ls, %ls", this, s1, s2);
55 for (; *s1 | *s2; ++s1, ++s2) {
56 c1 = utf_to_upper(*s1);
57 c2 = utf_to_upper(*s2);
58 if (c1 < c2) {
59 ret = -1;
60 goto out;
61 } else if (c1 > c2) {
62 ret = 1;
63 goto out;
64 }
65 }
66 out:
67 EFI_EXIT(EFI_SUCCESS);
68 return ret;
69 }
70
71 /**
72 * next_lower() - get next codepoint converted to lower case
73 *
74 * @string: pointer to u16 string, on return advanced by one codepoint
75 * Return: first codepoint of string converted to lower case
76 */
next_lower(const u16 ** string)77 static s32 next_lower(const u16 **string)
78 {
79 return utf_to_lower(utf16_get(string));
80 }
81
82 /**
83 * metai_match() - compare utf-16 string with a pattern string case-insenitively
84 *
85 * @string: string to compare
86 * @pattern: pattern string
87 *
88 * The pattern string may use these:
89 * - * matches >= 0 characters
90 * - ? matches 1 character
91 * - [<char1><char2>...<charN>] match any character in the set
92 * - [<char1>-<char2>] matches any character in the range
93 *
94 * This function is called my efi_metai_match().
95 *
96 * For '*' pattern searches this function calls itself recursively.
97 * Performance-wise this is suboptimal, especially for multiple '*' wildcards.
98 * But it results in simple code.
99 *
100 * Return: true if the string is matched.
101 */
metai_match(const u16 * string,const u16 * pattern)102 static bool metai_match(const u16 *string, const u16 *pattern)
103 {
104 s32 first, s, p;
105
106 for (; *string && *pattern;) {
107 const u16 *string_old = string;
108
109 s = next_lower(&string);
110 p = next_lower(&pattern);
111
112 switch (p) {
113 case '*':
114 /* Match 0 or more characters */
115 for (;; s = next_lower(&string)) {
116 if (metai_match(string_old, pattern))
117 return true;
118 if (!s)
119 return false;
120 string_old = string;
121 }
122 case '?':
123 /* Match any one character */
124 break;
125 case '[':
126 /* Match any character in the set */
127 p = next_lower(&pattern);
128 first = p;
129 if (first == ']')
130 /* Empty set */
131 return false;
132 p = next_lower(&pattern);
133 if (p == '-') {
134 /* Range */
135 p = next_lower(&pattern);
136 if (s < first || s > p)
137 return false;
138 p = next_lower(&pattern);
139 if (p != ']')
140 return false;
141 } else {
142 /* Set */
143 bool hit = false;
144
145 if (s == first)
146 hit = true;
147 for (; p && p != ']';
148 p = next_lower(&pattern)) {
149 if (p == s)
150 hit = true;
151 }
152 if (!hit || p != ']')
153 return false;
154 }
155 break;
156 default:
157 /* Match one character */
158 if (p != s)
159 return false;
160 }
161 }
162 if (!*pattern && !*string)
163 return true;
164 return false;
165 }
166
167 /**
168 * efi_metai_match() - compare utf-16 string with a pattern string
169 * case-insenitively
170 *
171 * @this: unicode collation protocol instance
172 * @string: string to compare
173 * @pattern: pattern string
174 *
175 * The pattern string may use these:
176 * - * matches >= 0 characters
177 * - ? matches 1 character
178 * - [<char1><char2>...<charN>] match any character in the set
179 * - [<char1>-<char2>] matches any character in the range
180 *
181 * This function implements the MetaMatch() service of the
182 * EFI_UNICODE_COLLATION_PROTOCOL2.
183 *
184 * Return: true if the string is matched.
185 */
efi_metai_match(struct efi_unicode_collation_protocol * this,const u16 * string,const u16 * pattern)186 static bool EFIAPI efi_metai_match(struct efi_unicode_collation_protocol *this,
187 const u16 *string, const u16 *pattern)
188 {
189 bool ret;
190
191 EFI_ENTRY("%p, %ls, %ls", this, string, pattern);
192 ret = metai_match(string, pattern);
193 EFI_EXIT(EFI_SUCCESS);
194 return ret;
195 }
196
197 /**
198 * efi_str_lwr() - convert to lower case
199 *
200 * @this: unicode collation protocol instance
201 * @string: string to convert
202 *
203 * The conversion is done in place. As long as upper and lower letters use the
204 * same number of words this does not pose a problem.
205 *
206 * This function implements the StrLwr() service of the
207 * EFI_UNICODE_COLLATION_PROTOCOL2.
208 */
efi_str_lwr(struct efi_unicode_collation_protocol * this,u16 * string)209 static void EFIAPI efi_str_lwr(struct efi_unicode_collation_protocol *this,
210 u16 *string)
211 {
212 EFI_ENTRY("%p, %ls", this, string);
213 for (; *string; ++string)
214 *string = utf_to_lower(*string);
215 EFI_EXIT(EFI_SUCCESS);
216 }
217
218 /**
219 * efi_str_upr() - convert to upper case
220 *
221 * @this: unicode collation protocol instance
222 * @string: string to convert
223 *
224 * The conversion is done in place. As long as upper and lower letters use the
225 * same number of words this does not pose a problem.
226 *
227 * This function implements the StrUpr() service of the
228 * EFI_UNICODE_COLLATION_PROTOCOL2.
229 */
efi_str_upr(struct efi_unicode_collation_protocol * this,u16 * string)230 static void EFIAPI efi_str_upr(struct efi_unicode_collation_protocol *this,
231 u16 *string)
232 {
233 EFI_ENTRY("%p, %ls", this, string);
234 for (; *string; ++string)
235 *string = utf_to_upper(*string);
236 EFI_EXIT(EFI_SUCCESS);
237 }
238
239 /**
240 * efi_fat_to_str() - convert an 8.3 file name from an OEM codepage to Unicode
241 *
242 * @this: unicode collation protocol instance
243 * @fat_size: size of the string to convert
244 * @fat: string to convert
245 * @string: converted string
246 *
247 * This function implements the FatToStr() service of the
248 * EFI_UNICODE_COLLATION_PROTOCOL2.
249 */
efi_fat_to_str(struct efi_unicode_collation_protocol * this,efi_uintn_t fat_size,char * fat,u16 * string)250 static void EFIAPI efi_fat_to_str(struct efi_unicode_collation_protocol *this,
251 efi_uintn_t fat_size, char *fat, u16 *string)
252 {
253 efi_uintn_t i;
254 u16 c;
255
256 EFI_ENTRY("%p, %zu, %s, %p", this, fat_size, fat, string);
257 for (i = 0; i < fat_size; ++i) {
258 c = (unsigned char)fat[i];
259 if (c > 0x80)
260 c = codepage[i - 0x80];
261 string[i] = c;
262 if (!c)
263 break;
264 }
265 string[i] = 0;
266 EFI_EXIT(EFI_SUCCESS);
267 }
268
269 /**
270 * efi_fat_to_str() - convert a utf-16 string to legal characters for a FAT
271 * file name in an OEM code page
272 *
273 * @this: unicode collation protocol instance
274 * @string: Unicode string to convert
275 * @fat_size: size of the target buffer
276 * @fat: converted string
277 *
278 * This function implements the StrToFat() service of the
279 * EFI_UNICODE_COLLATION_PROTOCOL2.
280 *
281 * Return: true if an illegal character was substituted by '_'.
282 */
efi_str_to_fat(struct efi_unicode_collation_protocol * this,const u16 * string,efi_uintn_t fat_size,char * fat)283 static bool EFIAPI efi_str_to_fat(struct efi_unicode_collation_protocol *this,
284 const u16 *string, efi_uintn_t fat_size,
285 char *fat)
286 {
287 efi_uintn_t i;
288 s32 c;
289 bool ret = false;
290
291 EFI_ENTRY("%p, %ls, %zu, %p", this, string, fat_size, fat);
292 for (i = 0; i < fat_size;) {
293 c = utf16_get(&string);
294 switch (c) {
295 /* Ignore period and space */
296 case '.':
297 case ' ':
298 continue;
299 case 0:
300 break;
301 }
302 c = utf_to_upper(c);
303 if (utf_to_cp(&c, codepage) ||
304 (c && (c < 0x20 || strchr(illegal, c)))) {
305 ret = true;
306 c = '_';
307 }
308
309 fat[i] = c;
310 if (!c)
311 break;
312 ++i;
313 }
314 EFI_EXIT(EFI_SUCCESS);
315 return ret;
316 }
317
318 const struct efi_unicode_collation_protocol efi_unicode_collation_protocol2 = {
319 .stri_coll = efi_stri_coll,
320 .metai_match = efi_metai_match,
321 .str_lwr = efi_str_lwr,
322 .str_upr = efi_str_upr,
323 .fat_to_str = efi_fat_to_str,
324 .str_to_fat = efi_str_to_fat,
325 .supported_languages = "en",
326 };
327