| 1 | /************************************************* |
| 2 | * Exim - an Internet mail transport agent * |
| 3 | *************************************************/ |
| 4 | |
| 5 | /* Copyright (c) Jeremy Harris 2015 - 2018 */ |
| 6 | /* See the file NOTICE for conditions of use and distribution. */ |
| 7 | |
| 8 | |
| 9 | #include "exim.h" |
| 10 | |
| 11 | #ifdef SUPPORT_I18N |
| 12 | |
| 13 | #ifdef SUPPORT_I18N_2008 |
| 14 | # include <idn2.h> |
| 15 | #else |
| 16 | # include <idna.h> |
| 17 | #endif |
| 18 | |
| 19 | #include <punycode.h> |
| 20 | #include <stringprep.h> |
| 21 | |
| 22 | static uschar * |
| 23 | string_localpart_alabel_to_utf8_(const uschar * alabel, uschar ** err); |
| 24 | |
| 25 | /**************************************************/ |
| 26 | |
| 27 | BOOL |
| 28 | string_is_utf8(const uschar * s) |
| 29 | { |
| 30 | uschar c; |
| 31 | if (s) while ((c = *s++)) if (c & 0x80) return TRUE; |
| 32 | return FALSE; |
| 33 | } |
| 34 | |
| 35 | static BOOL |
| 36 | string_is_alabel(const uschar * s) |
| 37 | { |
| 38 | return s[0] == 'x' && s[1] == 'n' && s[2] == '-' && s[3] == '-'; |
| 39 | } |
| 40 | |
| 41 | /**************************************************/ |
| 42 | /* Domain conversions. |
| 43 | The *err string pointer should be null before the call |
| 44 | |
| 45 | Return NULL for error, with optional errstr pointer filled in |
| 46 | */ |
| 47 | |
| 48 | uschar * |
| 49 | string_domain_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 50 | { |
| 51 | uschar * s1, * s; |
| 52 | int rc; |
| 53 | |
| 54 | #ifdef SUPPORT_I18N_2008 |
| 55 | /* Avoid lowercasing plain-ascii domains */ |
| 56 | if (!string_is_utf8(utf8)) |
| 57 | return string_copy(utf8); |
| 58 | |
| 59 | /* Only lowercase is accepted by the library call. A pity since we lose |
| 60 | any mixed-case annotation. This does not really matter for a domain. */ |
| 61 | { |
| 62 | uschar c; |
| 63 | for (s1 = s = US utf8; (c = *s1); s1++) if (!(c & 0x80) && isupper(c)) |
| 64 | { |
| 65 | s = string_copy(utf8); |
| 66 | for (s1 = s + (s1 - utf8); (c = *s1); s1++) if (!(c & 0x80) && isupper(c)) |
| 67 | *s1 = tolower(c); |
| 68 | break; |
| 69 | } |
| 70 | } |
| 71 | if ((rc = idn2_lookup_u8((const uint8_t *) s, &s1, IDN2_NFC_INPUT)) != IDN2_OK) |
| 72 | { |
| 73 | if (err) *err = US idn2_strerror(rc); |
| 74 | return NULL; |
| 75 | } |
| 76 | #else |
| 77 | s = US stringprep_utf8_nfkc_normalize(CCS utf8, -1); |
| 78 | if ( (rc = idna_to_ascii_8z(CCS s, CSS &s1, IDNA_ALLOW_UNASSIGNED)) |
| 79 | != IDNA_SUCCESS) |
| 80 | { |
| 81 | free(s); |
| 82 | if (err) *err = US idna_strerror(rc); |
| 83 | return NULL; |
| 84 | } |
| 85 | free(s); |
| 86 | #endif |
| 87 | s = string_copy(s1); |
| 88 | free(s1); |
| 89 | return s; |
| 90 | } |
| 91 | |
| 92 | |
| 93 | |
| 94 | uschar * |
| 95 | string_domain_alabel_to_utf8(const uschar * alabel, uschar ** err) |
| 96 | { |
| 97 | #ifdef SUPPORT_I18N_2008 |
| 98 | const uschar * label; |
| 99 | int sep = '.'; |
| 100 | gstring * g = NULL; |
| 101 | |
| 102 | while (label = string_nextinlist(&alabel, &sep, NULL, 0)) |
| 103 | if ( string_is_alabel(label) |
| 104 | && !(label = string_localpart_alabel_to_utf8_(label, err)) |
| 105 | ) |
| 106 | return NULL; |
| 107 | else |
| 108 | g = string_append_listele(g, '.', label); |
| 109 | return string_from_gstring(g); |
| 110 | |
| 111 | #else |
| 112 | |
| 113 | uschar * s1, * s; |
| 114 | int rc; |
| 115 | |
| 116 | if ( (rc = idna_to_unicode_8z8z(CCS alabel, CSS &s1, IDNA_USE_STD3_ASCII_RULES)) |
| 117 | != IDNA_SUCCESS) |
| 118 | { |
| 119 | if (err) *err = US idna_strerror(rc); |
| 120 | return NULL; |
| 121 | } |
| 122 | s = string_copy(s1); |
| 123 | free(s1); |
| 124 | return s; |
| 125 | #endif |
| 126 | } |
| 127 | |
| 128 | /**************************************************/ |
| 129 | /* localpart conversions */ |
| 130 | /* the *err string pointer should be null before the call */ |
| 131 | |
| 132 | |
| 133 | uschar * |
| 134 | string_localpart_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 135 | { |
| 136 | size_t ucs4_len; |
| 137 | punycode_uint * p; |
| 138 | size_t p_len; |
| 139 | uschar * res; |
| 140 | int rc; |
| 141 | |
| 142 | if (!string_is_utf8(utf8)) return string_copy(utf8); |
| 143 | |
| 144 | p = (punycode_uint *) stringprep_utf8_to_ucs4(CCS utf8, -1, &ucs4_len); |
| 145 | p_len = ucs4_len*4; /* this multiplier is pure guesswork */ |
| 146 | res = store_get(p_len+5); |
| 147 | |
| 148 | res[0] = 'x'; res[1] = 'n'; res[2] = res[3] = '-'; |
| 149 | |
| 150 | if ((rc = punycode_encode(ucs4_len, p, NULL, &p_len, CS res+4)) != PUNYCODE_SUCCESS) |
| 151 | { |
| 152 | DEBUG(D_expand) debug_printf("l_u2a: bad '%s'\n", punycode_strerror(rc)); |
| 153 | free(p); |
| 154 | if (err) *err = US punycode_strerror(rc); |
| 155 | return NULL; |
| 156 | } |
| 157 | p_len += 4; |
| 158 | free(p); |
| 159 | res[p_len] = '\0'; |
| 160 | return res; |
| 161 | } |
| 162 | |
| 163 | |
| 164 | static uschar * |
| 165 | string_localpart_alabel_to_utf8_(const uschar * alabel, uschar ** err) |
| 166 | { |
| 167 | size_t p_len; |
| 168 | punycode_uint * p; |
| 169 | int rc; |
| 170 | uschar * s, * res; |
| 171 | |
| 172 | DEBUG(D_expand) debug_printf("l_a2u: '%s'\n", alabel); |
| 173 | alabel += 4; |
| 174 | p_len = Ustrlen(alabel); |
| 175 | p = (punycode_uint *) store_get((p_len+1) * sizeof(*p)); |
| 176 | |
| 177 | if ((rc = punycode_decode(p_len, CCS alabel, &p_len, p, NULL)) != PUNYCODE_SUCCESS) |
| 178 | { |
| 179 | if (err) *err = US punycode_strerror(rc); |
| 180 | return NULL; |
| 181 | } |
| 182 | |
| 183 | s = US stringprep_ucs4_to_utf8(p, p_len, NULL, &p_len); |
| 184 | res = string_copyn(s, p_len); |
| 185 | free(s); |
| 186 | return res; |
| 187 | } |
| 188 | |
| 189 | |
| 190 | uschar * |
| 191 | string_localpart_alabel_to_utf8(const uschar * alabel, uschar ** err) |
| 192 | { |
| 193 | if (string_is_alabel(alabel)) |
| 194 | return string_localpart_alabel_to_utf8_(alabel, err); |
| 195 | |
| 196 | if (err) *err = US"bad alabel prefix"; |
| 197 | return NULL; |
| 198 | } |
| 199 | |
| 200 | |
| 201 | /**************************************************/ |
| 202 | /* Whole address conversion. |
| 203 | The *err string pointer should be null before the call. |
| 204 | |
| 205 | Return NULL on error, with (optional) errstring pointer filled in |
| 206 | */ |
| 207 | |
| 208 | uschar * |
| 209 | string_address_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 210 | { |
| 211 | const uschar * s; |
| 212 | uschar * l; |
| 213 | uschar * d; |
| 214 | |
| 215 | if (!*utf8) return string_copy(utf8); |
| 216 | |
| 217 | DEBUG(D_expand) debug_printf("addr from utf8 <%s>", utf8); |
| 218 | |
| 219 | for (s = utf8; *s; s++) |
| 220 | if (*s == '@') |
| 221 | { |
| 222 | l = string_copyn(utf8, s - utf8); |
| 223 | if ( !(l = string_localpart_utf8_to_alabel(l, err)) |
| 224 | || !(d = string_domain_utf8_to_alabel(++s, err)) |
| 225 | ) |
| 226 | return NULL; |
| 227 | l = string_sprintf("%s@%s", l, d); |
| 228 | DEBUG(D_expand) debug_printf(" -> <%s>\n", l); |
| 229 | return l; |
| 230 | } |
| 231 | |
| 232 | l = string_localpart_utf8_to_alabel(utf8, err); |
| 233 | DEBUG(D_expand) debug_printf(" -> <%s>\n", l); |
| 234 | return l; |
| 235 | } |
| 236 | |
| 237 | |
| 238 | |
| 239 | /************************************************* |
| 240 | * Report the library versions. * |
| 241 | *************************************************/ |
| 242 | |
| 243 | /* See a description in tls-openssl.c for an explanation of why this exists. |
| 244 | |
| 245 | Arguments: a FILE* to print the results to |
| 246 | Returns: nothing |
| 247 | */ |
| 248 | |
| 249 | void |
| 250 | utf8_version_report(FILE *f) |
| 251 | { |
| 252 | #ifdef SUPPORT_I18N_2008 |
| 253 | fprintf(f, "Library version: IDN2: Compile: %s\n" |
| 254 | " Runtime: %s\n", |
| 255 | IDN2_VERSION, |
| 256 | idn2_check_version(NULL)); |
| 257 | fprintf(f, "Library version: Stringprep: Compile: %s\n" |
| 258 | " Runtime: %s\n", |
| 259 | STRINGPREP_VERSION, |
| 260 | stringprep_check_version(NULL)); |
| 261 | #else |
| 262 | fprintf(f, "Library version: IDN: Compile: %s\n" |
| 263 | " Runtime: %s\n", |
| 264 | STRINGPREP_VERSION, |
| 265 | stringprep_check_version(NULL)); |
| 266 | #endif |
| 267 | } |
| 268 | |
| 269 | #endif /* whole file */ |
| 270 | |
| 271 | /* vi: aw ai sw=2 |
| 272 | */ |
| 273 | /* End of utf8.c */ |