NeoMutt  2022-04-29-178-g3b62e6
Teaching an old dog new tricks
DOXYGEN
idna.c
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1
29#include "config.h"
30#include <stdint.h>
31#include <stdio.h>
32#include "mutt/lib.h"
33#include "config/lib.h"
34#include "core/lib.h"
35#include "idna2.h"
36#ifdef HAVE_LIBIDN
37#include <stdbool.h>
38#include <string.h>
39#endif
40#ifdef HAVE_STRINGPREP_H
41#include <stringprep.h>
42#elif defined(HAVE_IDN_STRINGPREP_H)
43#include <idn/stringprep.h>
44#endif
45#define IDN2_SKIP_LIBIDN_COMPAT
46#ifdef HAVE_IDN2_H
47#include <idn2.h>
48#elif defined(HAVE_IDN_IDN2_H)
49#include <idn/idn2.h>
50#elif defined(HAVE_IDNA_H)
51#include <idna.h>
52#elif defined(HAVE_IDN_IDNA_H)
53#include <idn/idna.h>
54#endif
55
56#if defined(HAVE_IDN2_H) || defined(HAVE_IDN_IDN2_H)
57#define IDN_VERSION 2
58#elif defined(HAVE_IDNA_H) || defined(HAVE_IDN_IDNA_H)
59#define IDN_VERSION 1
60#endif
61
62#ifdef HAVE_LIBIDN
63/* Work around incompatibilities in the libidn API */
64#if (!defined(HAVE_IDNA_TO_ASCII_8Z) && defined(HAVE_IDNA_TO_ASCII_FROM_UTF8))
65#define idna_to_ascii_8z(input, output, flags) \
66 idna_to_ascii_from_utf8(input, output, (flags) &1, ((flags) &2) ? 1 : 0)
67#endif
68#if (!defined(HAVE_IDNA_TO_ASCII_LZ) && defined(HAVE_IDNA_TO_ASCII_FROM_LOCALE))
69#define idna_to_ascii_lz(input, output, flags) \
70 idna_to_ascii_from_locale(input, output, (flags) &1, ((flags) &2) ? 1 : 0)
71#endif
72#if (!defined(HAVE_IDNA_TO_UNICODE_8Z8Z) && defined(HAVE_IDNA_TO_UNICODE_UTF8_FROM_UTF8))
73#define idna_to_unicode_8z8z(input, output, flags) \
74 idna_to_unicode_utf8_from_utf8(input, output, (flags) &1, ((flags) &2) ? 1 : 0)
75#endif
76#endif /* HAVE_LIBIDN */
77
78#ifdef HAVE_LIBIDN
84static bool check_idn(char *domain)
85{
86 if (!domain)
87 return false;
88
89 if (mutt_istr_startswith(domain, "xn--"))
90 return true;
91
92 while ((domain = strchr(domain, '.')))
93 {
94 if (mutt_istr_startswith(++domain, "xn--"))
95 return true;
96 }
97
98 return false;
99}
100
113int mutt_idna_to_ascii_lz(const char *input, char **output, uint8_t flags)
114{
115 if (!input || !output)
116 return 1;
117
118#if (IDN_VERSION == 2)
119 return idn2_to_ascii_8z(input, output, flags | IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL);
120#else
121 return idna_to_ascii_lz(input, output, flags);
122#endif
123}
124#endif /* HAVE_LIBIDN */
125
144char *mutt_idna_intl_to_local(const char *user, const char *domain, uint8_t flags)
145{
146 char *mailbox = NULL;
147 char *reversed_user = NULL, *reversed_domain = NULL;
148 char *tmp = NULL;
149
150 char *local_user = mutt_str_dup(user);
151 char *local_domain = mutt_str_dup(domain);
152
153#ifdef HAVE_LIBIDN
154 bool is_idn_encoded = check_idn(local_domain);
155 const bool c_idn_decode = cs_subset_bool(NeoMutt->sub, "idn_decode");
156 if (is_idn_encoded && c_idn_decode)
157 {
158#if (IDN_VERSION == 2)
159 if (idn2_to_unicode_8z8z(local_domain, &tmp, IDN2_ALLOW_UNASSIGNED) != IDN2_OK)
160#else
161 if (idna_to_unicode_8z8z(local_domain, &tmp, IDNA_ALLOW_UNASSIGNED) != IDNA_SUCCESS)
162#endif
163 {
164 goto cleanup;
165 }
166 mutt_str_replace(&local_domain, tmp);
167 FREE(&tmp);
168 }
169#endif /* HAVE_LIBIDN */
170
171 /* we don't want charset-hook effects, so we set flags to 0 */
172 const char *const c_charset = cs_subset_string(NeoMutt->sub, "charset");
173 if (mutt_ch_convert_string(&local_user, "utf-8", c_charset, MUTT_ICONV_NO_FLAGS) != 0)
174 goto cleanup;
175
176 if (mutt_ch_convert_string(&local_domain, "utf-8", c_charset, MUTT_ICONV_NO_FLAGS) != 0)
177 goto cleanup;
178
179 /* make sure that we can convert back and come out with the same
180 * user and domain name. */
181 if ((flags & MI_MAY_BE_IRREVERSIBLE) == 0)
182 {
183 reversed_user = mutt_str_dup(local_user);
184
185 if (mutt_ch_convert_string(&reversed_user, c_charset, "utf-8", MUTT_ICONV_NO_FLAGS) != 0)
186 {
187 mutt_debug(LL_DEBUG1, "Not reversible. Charset conv to utf-8 failed for user = '%s'\n",
188 reversed_user);
189 goto cleanup;
190 }
191
192 if (!mutt_istr_equal(user, reversed_user))
193 {
194 mutt_debug(LL_DEBUG1, "#1 Not reversible. orig = '%s', reversed = '%s'\n",
195 user, reversed_user);
196 goto cleanup;
197 }
198
199 reversed_domain = mutt_str_dup(local_domain);
200
201 if (mutt_ch_convert_string(&reversed_domain, c_charset, "utf-8", MUTT_ICONV_NO_FLAGS) != 0)
202 {
203 mutt_debug(LL_DEBUG1, "Not reversible. Charset conv to utf-8 failed for domain = '%s'\n",
204 reversed_domain);
205 goto cleanup;
206 }
207
208#ifdef HAVE_LIBIDN
209 /* If the original domain was UTF-8, idna encoding here could
210 * produce a non-matching domain! Thus we only want to do the
211 * idna_to_ascii_8z() if the original domain was IDNA encoded. */
212 if (is_idn_encoded && c_idn_decode)
213 {
214#if (IDN_VERSION == 2)
215 if (idn2_to_ascii_8z(reversed_domain, &tmp,
216 IDN2_ALLOW_UNASSIGNED | IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL) != IDN2_OK)
217#else
218 if (idna_to_ascii_8z(reversed_domain, &tmp, IDNA_ALLOW_UNASSIGNED) != IDNA_SUCCESS)
219#endif
220 {
221 mutt_debug(LL_DEBUG1, "Not reversible. idna_to_ascii_8z failed for domain = '%s'\n",
222 reversed_domain);
223 goto cleanup;
224 }
225 mutt_str_replace(&reversed_domain, tmp);
226 }
227#endif /* HAVE_LIBIDN */
228
229 if (!mutt_istr_equal(domain, reversed_domain))
230 {
231 mutt_debug(LL_DEBUG1, "#2 Not reversible. orig = '%s', reversed = '%s'\n",
232 domain, reversed_domain);
233 goto cleanup;
234 }
235 }
236
237 mailbox = mutt_mem_malloc(mutt_str_len(local_user) + mutt_str_len(local_domain) + 2);
238 sprintf(mailbox, "%s@%s", NONULL(local_user), NONULL(local_domain));
239
240cleanup:
241 FREE(&local_user);
242 FREE(&local_domain);
243 FREE(&tmp);
244 FREE(&reversed_domain);
245 FREE(&reversed_user);
246
247 return mailbox;
248}
249
264char *mutt_idna_local_to_intl(const char *user, const char *domain)
265{
266 char *mailbox = NULL;
267 char *tmp = NULL;
268
269 char *intl_user = mutt_str_dup(user);
270 char *intl_domain = mutt_str_dup(domain);
271
272 /* we don't want charset-hook effects, so we set flags to 0 */
273 const char *const c_charset = cs_subset_string(NeoMutt->sub, "charset");
274 if (mutt_ch_convert_string(&intl_user, c_charset, "utf-8", MUTT_ICONV_NO_FLAGS) != 0)
275 goto cleanup;
276
277 if (mutt_ch_convert_string(&intl_domain, c_charset, "utf-8", MUTT_ICONV_NO_FLAGS) != 0)
278 goto cleanup;
279
280#ifdef HAVE_LIBIDN
281 const bool c_idn_encode = cs_subset_bool(NeoMutt->sub, "idn_encode");
282 if (c_idn_encode)
283 {
284#if (IDN_VERSION == 2)
285 if (idn2_to_ascii_8z(intl_domain, &tmp,
286 IDN2_ALLOW_UNASSIGNED | IDN2_NFC_INPUT | IDN2_NONTRANSITIONAL) != IDN2_OK)
287#else
288 if (idna_to_ascii_8z(intl_domain, &tmp, IDNA_ALLOW_UNASSIGNED) != IDNA_SUCCESS)
289#endif
290 {
291 goto cleanup;
292 }
293 mutt_str_replace(&intl_domain, tmp);
294 }
295#endif /* HAVE_LIBIDN */
296
297 mailbox = mutt_mem_malloc(mutt_str_len(intl_user) + mutt_str_len(intl_domain) + 2);
298 sprintf(mailbox, "%s@%s", NONULL(intl_user), NONULL(intl_domain));
299
300cleanup:
301 FREE(&intl_user);
302 FREE(&intl_domain);
303 FREE(&tmp);
304
305 return mailbox;
306}
307
314const char *mutt_idna_print_version(void)
315{
316 static char vstring[256];
317
318#ifdef HAVE_LIBIDN
319#if (IDN_VERSION == 2)
320 snprintf(vstring, sizeof(vstring), "libidn2: %s (compiled with %s)",
321 idn2_check_version(NULL), IDN2_VERSION);
322#elif (IDN_VERSION == 1)
323 snprintf(vstring, sizeof(vstring), "libidn: %s (compiled with %s)",
324 stringprep_check_version(NULL), STRINGPREP_VERSION);
325#endif
326#endif /* HAVE_LIBIDN */
327
328 return vstring;
329}
const char * cs_subset_string(const struct ConfigSubset *sub, const char *name)
Get a string config item by name.
Definition: helpers.c:317
bool cs_subset_bool(const struct ConfigSubset *sub, const char *name)
Get a boolean config item by name.
Definition: helpers.c:73
Convenience wrapper for the config headers.
Convenience wrapper for the core headers.
#define mutt_debug(LEVEL,...)
Definition: logging.h:84
Handling of international domain names.
int mutt_idna_to_ascii_lz(const char *input, char **output, uint8_t flags)
#define MI_MAY_BE_IRREVERSIBLE
Definition: idna2.h:30
const char * mutt_idna_print_version(void)
Create an IDN version string.
Definition: idna.c:314
char * mutt_idna_local_to_intl(const char *user, const char *domain)
Convert an email's domain to Punycode.
Definition: idna.c:264
char * mutt_idna_intl_to_local(const char *user, const char *domain, uint8_t flags)
Convert an email's domain from Punycode.
Definition: idna.c:144
@ LL_DEBUG1
Log at debug level 1.
Definition: logging.h:40
void * mutt_mem_malloc(size_t size)
Allocate memory on the heap.
Definition: memory.c:90
#define FREE(x)
Definition: memory.h:43
int mutt_ch_convert_string(char **ps, const char *from, const char *to, uint8_t flags)
Convert a string between encodings.
Definition: charset.c:752
#define MUTT_ICONV_NO_FLAGS
No flags are set.
Definition: charset.h:71
Convenience wrapper for the library headers.
bool mutt_istr_equal(const char *a, const char *b)
Compare two strings, ignoring case.
Definition: string.c:796
char * mutt_str_dup(const char *str)
Copy a string, safely.
Definition: string.c:250
size_t mutt_str_len(const char *a)
Calculate the length of a string, safely.
Definition: string.c:544
size_t mutt_istr_startswith(const char *str, const char *prefix)
Check whether a string starts with a prefix, ignoring case.
Definition: string.c:239
char * mutt_str_replace(char **p, const char *s)
Replace one string with another.
Definition: string.c:326
#define NONULL(x)
Definition: string2.h:37
Container for Accounts, Notifications.
Definition: neomutt.h:37
struct ConfigSubset * sub
Inherited config items.
Definition: neomutt.h:39