| 1 | /************************************************* |
| 2 | * Exim - an Internet mail transport agent * |
| 3 | *************************************************/ |
| 4 | |
| 5 | /* Copyright (c) Jeremy Harris 2015 */ |
| 6 | /* See the file NOTICE for conditions of use and distribution. */ |
| 7 | |
| 8 | |
| 9 | #include "exim.h" |
| 10 | |
| 11 | #ifdef EXPERIMENTAL_INTERNATIONAL |
| 12 | |
| 13 | #include <idna.h> |
| 14 | #include <punycode.h> |
| 15 | #include <stringprep.h> |
| 16 | |
| 17 | BOOL |
| 18 | string_is_utf8(const uschar * s) |
| 19 | { |
| 20 | uschar c; |
| 21 | while ((c = *s++)) if (c & 0x80) return TRUE; |
| 22 | return FALSE; |
| 23 | } |
| 24 | |
| 25 | /**************************************************/ |
| 26 | /* Domain conversions */ |
| 27 | /* the *err string pointer should be null before the call */ |
| 28 | |
| 29 | uschar * |
| 30 | string_domain_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 31 | { |
| 32 | uschar * s1; |
| 33 | uschar * s; |
| 34 | int rc; |
| 35 | |
| 36 | s = US stringprep_utf8_nfkc_normalize(CCS utf8, -1); |
| 37 | if ( (rc = idna_to_ascii_8z(CCS s, CSS &s1, IDNA_ALLOW_UNASSIGNED)) |
| 38 | != IDNA_SUCCESS) |
| 39 | { |
| 40 | free(s); |
| 41 | if (err) *err = US idna_strerror(rc); |
| 42 | return NULL; |
| 43 | } |
| 44 | free(s); |
| 45 | s = string_copy(s1); |
| 46 | free(s1); |
| 47 | return s; |
| 48 | } |
| 49 | |
| 50 | |
| 51 | |
| 52 | uschar * |
| 53 | string_domain_alabel_to_utf8(const uschar * alabel, uschar ** err) |
| 54 | { |
| 55 | uschar * s1; |
| 56 | uschar * s; |
| 57 | int rc; |
| 58 | |
| 59 | if ( (rc = idna_to_unicode_8z8z(CCS alabel, CSS &s1, IDNA_USE_STD3_ASCII_RULES)) |
| 60 | != IDNA_SUCCESS) |
| 61 | { |
| 62 | if (err) *err = US idna_strerror(rc); |
| 63 | return NULL; |
| 64 | } |
| 65 | s = string_copy(s1); |
| 66 | free(s1); |
| 67 | return s; |
| 68 | } |
| 69 | |
| 70 | /**************************************************/ |
| 71 | /* localpart conversions */ |
| 72 | /* the *err string pointer should be null before the call */ |
| 73 | |
| 74 | |
| 75 | uschar * |
| 76 | string_localpart_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 77 | { |
| 78 | size_t ucs4_len; |
| 79 | punycode_uint * p; |
| 80 | size_t p_len; |
| 81 | uschar * res; |
| 82 | int rc; |
| 83 | |
| 84 | if (!string_is_utf8(utf8)) return string_copy(utf8); |
| 85 | |
| 86 | p = (punycode_uint *) stringprep_utf8_to_ucs4(CCS utf8, -1, &ucs4_len); |
| 87 | p_len = ucs4_len*4; /* this multiplier is pure guesswork */ |
| 88 | res = store_get(p_len+5); |
| 89 | |
| 90 | res[0] = 'x'; res[1] = 'n'; res[2] = res[3] = '-'; |
| 91 | |
| 92 | if ((rc = punycode_encode(ucs4_len, p, NULL, &p_len, CS res+4)) != PUNYCODE_SUCCESS) |
| 93 | { |
| 94 | DEBUG(D_expand) debug_printf("l_u2a: bad '%s'\n", punycode_strerror(rc)); |
| 95 | free(p); |
| 96 | if (err) *err = US punycode_strerror(rc); |
| 97 | return NULL; |
| 98 | } |
| 99 | p_len += 4; |
| 100 | free(p); |
| 101 | res[p_len] = '\0'; |
| 102 | return res; |
| 103 | } |
| 104 | |
| 105 | |
| 106 | uschar * |
| 107 | string_localpart_alabel_to_utf8(const uschar * alabel, uschar ** err) |
| 108 | { |
| 109 | size_t p_len = Ustrlen(alabel); |
| 110 | punycode_uint * p; |
| 111 | uschar * s; |
| 112 | uschar * res; |
| 113 | int rc; |
| 114 | |
| 115 | if (alabel[0] != 'x' || alabel[1] != 'n' || alabel[2] != '-' || alabel[3] != '-') |
| 116 | { |
| 117 | if (err) *err = US"bad alabel prefix"; |
| 118 | return NULL; |
| 119 | } |
| 120 | |
| 121 | p_len -= 4; |
| 122 | p = (punycode_uint *) store_get((p_len+1) * sizeof(*p)); |
| 123 | |
| 124 | if ((rc = punycode_decode(p_len, CCS alabel+4, &p_len, p, NULL)) != PUNYCODE_SUCCESS) |
| 125 | { |
| 126 | if (err) *err = US punycode_strerror(rc); |
| 127 | return NULL; |
| 128 | } |
| 129 | |
| 130 | s = US stringprep_ucs4_to_utf8(p, p_len, NULL, &p_len); |
| 131 | res = string_copyn(s, p_len); |
| 132 | free(s); |
| 133 | return res; |
| 134 | } |
| 135 | |
| 136 | |
| 137 | /**************************************************/ |
| 138 | /* whole address conversion */ |
| 139 | /* the *err string pointer should be null before the call */ |
| 140 | |
| 141 | uschar * |
| 142 | string_address_utf8_to_alabel(const uschar * utf8, uschar ** err) |
| 143 | { |
| 144 | const uschar * s; |
| 145 | uschar * l; |
| 146 | uschar * d; |
| 147 | |
| 148 | if (!*utf8) return string_copy(utf8); |
| 149 | |
| 150 | DEBUG(D_expand) debug_printf("addr from utf8 <%s>", utf8); |
| 151 | |
| 152 | for (s = utf8; *s; s++) |
| 153 | if (*s == '@') |
| 154 | { |
| 155 | l = string_copyn(utf8, s - utf8); |
| 156 | if ( (l = string_localpart_utf8_to_alabel(l, err), err && *err) |
| 157 | || (d = string_domain_utf8_to_alabel(++s, err), err && *err) |
| 158 | ) |
| 159 | return NULL; |
| 160 | l = string_sprintf("%s@%s", l, d); |
| 161 | DEBUG(D_expand) debug_printf(" -> <%s>\n", l); |
| 162 | return l; |
| 163 | } |
| 164 | |
| 165 | l = string_localpart_utf8_to_alabel(utf8, err); |
| 166 | DEBUG(D_expand) debug_printf(" -> <%s>\n", l); |
| 167 | return l; |
| 168 | } |
| 169 | |
| 170 | |
| 171 | |
| 172 | /************************************************* |
| 173 | * Report the library versions. * |
| 174 | *************************************************/ |
| 175 | |
| 176 | /* See a description in tls-openssl.c for an explanation of why this exists. |
| 177 | |
| 178 | Arguments: a FILE* to print the results to |
| 179 | Returns: nothing |
| 180 | */ |
| 181 | |
| 182 | void |
| 183 | utf8_version_report(FILE *f) |
| 184 | { |
| 185 | fprintf(f, "Library version: IDN: Compile: %s\n" |
| 186 | " Runtime: %s\n", |
| 187 | STRINGPREP_VERSION, |
| 188 | stringprep_check_version(NULL)); |
| 189 | } |
| 190 | |
| 191 | #endif /* whole file */ |
| 192 | |
| 193 | /* vi: aw ai sw=2 |
| 194 | */ |
| 195 | /* End of utf8.c */ |