| /* |
| * Copyright (C) 1999-2001, 2008, 2016 Free Software Foundation, Inc. |
| * This file is part of the GNU LIBICONV Library. |
| * |
| * The GNU LIBICONV Library is free software; you can redistribute it |
| * and/or modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either version 2.1 |
| * of the License, or (at your option) any later version. |
| * |
| * The GNU LIBICONV Library is distributed in the hope that it will be |
| * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with the GNU LIBICONV Library; see the file COPYING.LIB. |
| * If not, see <https://www.gnu.org/licenses/>. |
| */ |
| |
| /* |
| * UTF-7 |
| */ |
| |
| /* Specification: RFC 2152 (and old RFC 1641, RFC 1642) */ |
| /* The original Base64 encoding is defined in RFC 2045. */ |
| |
| /* Set of direct characters: |
| * A-Z a-z 0-9 ' ( ) , - . / : ? space tab lf cr |
| */ |
| static const unsigned char direct_tab[128/8] = { |
| 0x00, 0x26, 0x00, 0x00, 0x81, 0xf3, 0xff, 0x87, |
| 0xfe, 0xff, 0xff, 0x07, 0xfe, 0xff, 0xff, 0x07, |
| }; |
| #define isdirect(ch) ((ch) < 128 && ((direct_tab[(ch)>>3] >> (ch & 7)) & 1)) |
| |
| /* Set of direct and optional direct characters: |
| * A-Z a-z 0-9 ' ( ) , - . / : ? space tab lf cr |
| * ! " # $ % & * ; < = > @ [ ] ^ _ ` { | } |
| */ |
| static const unsigned char xdirect_tab[128/8] = { |
| 0x00, 0x26, 0x00, 0x00, 0xff, 0xf7, 0xff, 0xff, |
| 0xff, 0xff, 0xff, 0xef, 0xff, 0xff, 0xff, 0x3f, |
| }; |
| #define isxdirect(ch) ((ch) < 128 && ((xdirect_tab[(ch)>>3] >> (ch & 7)) & 1)) |
| |
| /* Set of base64 characters, extended: |
| * A-Z a-z 0-9 + / - |
| */ |
| static const unsigned char xbase64_tab[128/8] = { |
| 0x00, 0x00, 0x00, 0x00, 0x00, 0xa8, 0xff, 0x03, |
| 0xfe, 0xff, 0xff, 0x07, 0xfe, 0xff, 0xff, 0x07, |
| }; |
| #define isxbase64(ch) ((ch) < 128 && ((xbase64_tab[(ch)>>3] >> (ch & 7)) & 1)) |
| |
| /* |
| * The state is structured as follows: |
| * bit 1..0: shift |
| * bit 7..2: data |
| * Precise meaning: |
| * shift data |
| * 0 0 not inside base64 encoding |
| * 1 0 inside base64, no pending bits |
| * 2 XXXX00 inside base64, 4 bits remain from 2nd byte |
| * 3 XX0000 inside base64, 2 bits remain from 3rd byte |
| */ |
| |
| static int |
| utf7_mbtowc (conv_t conv, ucs4_t *pwc, const unsigned char *s, size_t n) |
| { |
| state_t state = conv->istate; |
| int count = 0; /* number of input bytes already read */ |
| if (state & 3) |
| goto active; |
| else |
| goto inactive; |
| |
| inactive: |
| { |
| /* Here (state & 3) == 0 */ |
| if (n < count+1) |
| goto none; |
| { |
| unsigned char c = *s; |
| if (isxdirect(c)) { |
| *pwc = (ucs4_t) c; |
| conv->istate = state; |
| return count+1; |
| } |
| if (c == '+') { |
| if (n < count+2) |
| goto none; |
| if (s[1] == '-') { |
| *pwc = (ucs4_t) '+'; |
| conv->istate = state; |
| return count+2; |
| } |
| s++; count++; |
| state = 1; |
| goto active; |
| } |
| goto ilseq; |
| } |
| } |
| |
| active: |
| { |
| /* base64 encoding active */ |
| unsigned int wc = 0; |
| state_t base64state = state; |
| unsigned int kmax = 2; /* number of payload bytes to read */ |
| unsigned int k = 0; /* number of payload bytes already read */ |
| unsigned int base64count = 0; /* number of base64 bytes already read */ |
| for (;;) { |
| unsigned char c = *s; |
| unsigned int i; |
| if (c >= 'A' && c <= 'Z') |
| i = c-'A'; |
| else if (c >= 'a' && c <= 'z') |
| i = c-'a'+26; |
| else if (c >= '0' && c <= '9') |
| i = c-'0'+52; |
| else if (c == '+') |
| i = 62; |
| else if (c == '/') |
| i = 63; |
| else { |
| /* c terminates base64 encoding */ |
| if (base64state & -4) |
| goto ilseq; /* data must be 0, otherwise illegal */ |
| if (base64count) |
| goto ilseq; /* partial UTF-16 characters are invalid */ |
| if (c == '-') { |
| s++; count++; |
| } |
| state = 0; |
| goto inactive; |
| } |
| s++; base64count++; |
| /* read 6 bits: 0 <= i < 64 */ |
| switch (base64state & 3) { |
| case 1: /* inside base64, no pending bits */ |
| base64state = (i << 2) | 0; break; |
| case 0: /* inside base64, 6 bits remain from 1st byte */ |
| wc = (wc << 8) | (base64state & -4) | (i >> 4); k++; |
| base64state = ((i & 15) << 4) | 2; break; |
| case 2: /* inside base64, 4 bits remain from 2nd byte */ |
| wc = (wc << 8) | (base64state & -4) | (i >> 2); k++; |
| base64state = ((i & 3) << 6) | 3; break; |
| case 3: /* inside base64, 2 bits remain from 3rd byte */ |
| wc = (wc << 8) | (base64state & -4) | i; k++; |
| base64state = 1; break; |
| } |
| if (k == kmax) { |
| /* UTF-16: When we see a High Surrogate, we must also decode |
| the following Low Surrogate. */ |
| if (kmax == 2 && (wc >= 0xd800 && wc < 0xdc00)) |
| kmax = 4; |
| else |
| break; |
| } |
| if (n < count+base64count+1) |
| goto none; |
| } |
| /* Here k = kmax > 0, hence base64count > 0. */ |
| if ((base64state & 3) == 0) abort(); |
| if (kmax == 4) { |
| ucs4_t wc1 = wc >> 16; |
| ucs4_t wc2 = wc & 0xffff; |
| if (!(wc1 >= 0xd800 && wc1 < 0xdc00)) abort(); |
| if (!(wc2 >= 0xdc00 && wc2 < 0xe000)) goto ilseq; |
| *pwc = 0x10000 + ((wc1 - 0xd800) << 10) + (wc2 - 0xdc00); |
| } else { |
| *pwc = wc; |
| } |
| conv->istate = base64state; |
| return count+base64count; |
| } |
| |
| none: |
| conv->istate = state; |
| return RET_TOOFEW(count); |
| |
| ilseq: |
| conv->istate = state; |
| return RET_SHIFT_ILSEQ(count); |
| } |
| |
| /* |
| * The state is structured as follows: |
| * bit 1..0: shift |
| * bit 7..2: data |
| * Precise meaning: |
| * shift data |
| * 0 0 not inside base64 encoding |
| * 1 0 inside base64, no pending bits |
| * 2 XX00 inside base64, 2 bits known for 2nd byte |
| * 3 XXXX inside base64, 4 bits known for 3rd byte |
| */ |
| |
| /* Define this to 1 if you want the so-called "optional direct" characters |
| ! " # $ % & * ; < = > @ [ ] ^ _ ` { | } |
| to be encoded. Define to 0 if you want them to be passed straight through, |
| like the so-called "direct" characters. |
| We set this to 1 because it's safer. |
| */ |
| #define UTF7_ENCODE_OPTIONAL_CHARS 1 |
| |
| static int |
| utf7_wctomb (conv_t conv, unsigned char *r, ucs4_t iwc, size_t n) |
| { |
| state_t state = conv->ostate; |
| unsigned int wc = iwc; |
| int count = 0; |
| if (state & 3) |
| goto active; |
| |
| /*inactive:*/ |
| { |
| if (UTF7_ENCODE_OPTIONAL_CHARS ? isdirect(wc) : isxdirect(wc)) { |
| r[0] = (unsigned char) wc; |
| /*conv->ostate = state;*/ |
| return 1; |
| } else { |
| *r++ = '+'; |
| if (wc == '+') { |
| if (n < 2) |
| return RET_TOOSMALL; |
| *r = '-'; |
| /*conv->ostate = state;*/ |
| return 2; |
| } |
| count = 1; |
| state = 1; |
| goto active; |
| } |
| } |
| |
| active: |
| { |
| /* base64 encoding active */ |
| if (UTF7_ENCODE_OPTIONAL_CHARS ? isdirect(wc) : isxdirect(wc)) { |
| /* deactivate base64 encoding */ |
| count += ((state & 3) >= 2 ? 1 : 0) + (isxbase64(wc) ? 1 : 0) + 1; |
| if (n < count) |
| return RET_TOOSMALL; |
| if ((state & 3) >= 2) { |
| unsigned int i = state & -4; |
| unsigned char c; |
| if (i < 26) |
| c = i+'A'; |
| else if (i < 52) |
| c = i-26+'a'; |
| else if (i < 62) |
| c = i-52+'0'; |
| else if (i == 62) |
| c = '+'; |
| else if (i == 63) |
| c = '/'; |
| else |
| abort(); |
| *r++ = c; |
| } |
| if (isxbase64(wc)) |
| *r++ = '-'; |
| state = 0; |
| *r++ = (unsigned char) wc; |
| conv->ostate = state; |
| return count; |
| } else { |
| unsigned int k; /* number of payload bytes to write */ |
| if (wc < 0x10000) { |
| k = 2; |
| count += ((state & 3) >= 2 ? 3 : 2); |
| } else if (wc < 0x110000) { |
| unsigned int wc1 = 0xd800 + ((wc - 0x10000) >> 10); |
| unsigned int wc2 = 0xdc00 + ((wc - 0x10000) & 0x3ff); |
| wc = (wc1 << 16) | wc2; |
| k = 4; |
| count += ((state & 3) >= 3 ? 6 : 5); |
| } else |
| return RET_ILUNI; |
| if (n < count) |
| return RET_TOOSMALL; |
| for (;;) { |
| unsigned int i; |
| unsigned char c; |
| switch (state & 3) { |
| case 0: /* inside base64, 6 bits known for 4th byte */ |
| c = (state & -4) >> 2; state = 1; break; |
| case 1: /* inside base64, no pending bits */ |
| i = (wc >> (8 * --k)) & 0xff; |
| c = i >> 2; state = ((i & 3) << 4) | 2; break; |
| case 2: /* inside base64, 2 bits known for 2nd byte */ |
| i = (wc >> (8 * --k)) & 0xff; |
| c = (state & -4) | (i >> 4); state = ((i & 15) << 2) | 3; break; |
| case 3: /* inside base64, 4 bits known for 3rd byte */ |
| i = (wc >> (8 * --k)) & 0xff; |
| c = (state & -4) | (i >> 6); state = ((i & 63) << 2) | 0; break; |
| default: abort(); /* stupid gcc */ |
| } |
| if (c < 26) |
| c = c+'A'; |
| else if (c < 52) |
| c = c-26+'a'; |
| else if (c < 62) |
| c = c-52+'0'; |
| else if (c == 62) |
| c = '+'; |
| else if (c == 63) |
| c = '/'; |
| else |
| abort(); |
| *r++ = c; |
| if ((state & 3) && (k == 0)) |
| break; |
| } |
| conv->ostate = state; |
| return count; |
| } |
| } |
| } |
| |
| static int |
| utf7_reset (conv_t conv, unsigned char *r, size_t n) |
| { |
| state_t state = conv->ostate; |
| if (state & 3) { |
| /* deactivate base64 encoding */ |
| unsigned int count = ((state & 3) >= 2 ? 1 : 0) + 1; |
| if (n < count) |
| return RET_TOOSMALL; |
| if ((state & 3) >= 2) { |
| unsigned int i = state & -4; |
| unsigned char c; |
| if (i < 26) |
| c = i+'A'; |
| else if (i < 52) |
| c = i-26+'a'; |
| else if (i < 62) |
| c = i-52+'0'; |
| else if (i == 62) |
| c = '+'; |
| else if (i == 63) |
| c = '/'; |
| else |
| abort(); |
| *r++ = c; |
| } |
| *r++ = '-'; |
| /* conv->ostate = 0; will be done by the caller */ |
| return count; |
| } else |
| return 0; |
| } |
