/* * Copyright (c) 1998-2003 Carnegie Mellon University. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The name "Carnegie Mellon University" must not be used to * endorse or promote products derived from this software without * prior written permission. For permission or any other legal * details, please contact * Office of Technology Transfer * Carnegie Mellon University * 5000 Forbes Avenue * Pittsburgh, PA 15213-3890 * (412) 268-4387, fax: (412) 268-7395 * tech-transfer@andrew.cmu.edu * * 4. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by Computing Services * at Carnegie Mellon University (http://www.cmu.edu/computing/)." * * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * * derived from chris newman's code */ /* $Id: imapurl.c,v 1.5 2005/03/05 00:37:14 dasenbro Exp $ */ #include #include #include #include /* hexadecimal lookup table */ static const char hex[] = "0123456789ABCDEF"; /* URL unsafe printable characters */ static const char urlunsafe[] = " \"#%&+:;<=>?@[\\]^`{|}"; /* UTF7 modified base64 alphabet */ static const char base64chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,"; #define UNDEFINED 64 /* UTF16 definitions */ #define UTF16MASK 0x03FFUL #define UTF16SHIFT 10 #define UTF16BASE 0x10000UL #define UTF16HIGHSTART 0xD800UL #define UTF16HIGHEND 0xDBFFUL #define UTF16LOSTART 0xDC00UL #define UTF16LOEND 0xDFFFUL /* Convert an IMAP mailbox to a URL path * dst needs to have roughly 4 times the storage space of src * Hex encoding can triple the size of the input * UTF-7 can be slightly denser than UTF-8 * (worst case: 8 octets UTF-7 becomes 9 octets UTF-8) */ static void MailboxToURL(char *dst, const char *src) { unsigned char c, i, bitcount; unsigned long ucs4, utf16, bitbuf; unsigned char base64[256], utf8[6]; /* initialize modified base64 decoding table */ memset(base64, UNDEFINED, sizeof (base64)); for (i = 0; i < sizeof (base64chars); ++i) { base64[(int) base64chars[i]] = i; } /* loop until end of string */ while (*src != '\0') { c = *src++; /* deal with literal characters and &- */ if (c != '&' || *src == '-') { if (c < ' ' || c > '~' || strchr(urlunsafe, c) != NULL) { /* hex encode if necessary */ dst[0] = '%'; dst[1] = hex[c >> 4]; dst[2] = hex[c & 0x0f]; dst += 3; } else { /* encode literally */ *dst++ = c; } /* skip over the '-' if this is an &- sequence */ if (c == '&') ++src; } else { /* convert modified UTF-7 -> UTF-16 -> UCS-4 -> UTF-8 -> HEX */ bitbuf = 0; bitcount = 0; ucs4 = 0; while ((c = base64[(unsigned char) *src]) != UNDEFINED) { ++src; bitbuf = (bitbuf << 6) | c; bitcount += 6; /* enough bits for a UTF-16 character? */ if (bitcount >= 16) { bitcount -= 16; utf16 = (bitcount ? bitbuf >> bitcount : bitbuf) & 0xffff; /* convert UTF16 to UCS4 */ if (utf16 >= UTF16HIGHSTART && utf16 <= UTF16HIGHEND) { ucs4 = (utf16 - UTF16HIGHSTART) << UTF16SHIFT; continue; } else if (utf16 >= UTF16LOSTART && utf16 <= UTF16LOEND) { ucs4 += utf16 - UTF16LOSTART + UTF16BASE; } else { ucs4 = utf16; } /* convert UTF-16 range of UCS4 to UTF-8 */ if (ucs4 <= 0x7fUL) { utf8[0] = ucs4; i = 1; } else if (ucs4 <= 0x7ffUL) { utf8[0] = 0xc0 | (ucs4 >> 6); utf8[1] = 0x80 | (ucs4 & 0x3f); i = 2; } else if (ucs4 <= 0xffffUL) { utf8[0] = 0xe0 | (ucs4 >> 12); utf8[1] = 0x80 | ((ucs4 >> 6) & 0x3f); utf8[2] = 0x80 | (ucs4 & 0x3f); i = 3; } else { utf8[0] = 0xf0 | (ucs4 >> 18); utf8[1] = 0x80 | ((ucs4 >> 12) & 0x3f); utf8[2] = 0x80 | ((ucs4 >> 6) & 0x3f); utf8[3] = 0x80 | (ucs4 & 0x3f); i = 4; } /* convert utf8 to hex */ for (c = 0; c < i; ++c) { dst[0] = '%'; dst[1] = hex[utf8[c] >> 4]; dst[2] = hex[utf8[c] & 0x0f]; dst += 3; } } } /* skip over trailing '-' in modified UTF-7 encoding */ if (*src == '-') ++src; } } /* terminate destination string */ *dst = '\0'; } /* Convert hex coded UTF-8 URL path to modified UTF-7 IMAP mailbox * dst should be about twice the length of src to deal with non-hex * coded URLs */ static void URLtoMailbox(char *dst, char *src) { unsigned int utf8pos = 0, utf8total, i, c, utf7mode, bitstogo, utf16flag; unsigned long ucs4 = 0, bitbuf = 0; unsigned char hextab[256]; /* initialize hex lookup table */ memset(hextab, 0, sizeof (hextab)); for (i = 0; i < sizeof (hex); ++i) { hextab[(int) hex[i]] = i; if (isupper((unsigned char) hex[i])) hextab[tolower(hex[i])] = i; } utf7mode = 0; /* is the output UTF7 currently in base64 mode? */ utf8total = 0; /* how many octets is the current input UTF-8 char; 0 == between characters */ bitstogo = 0; /* bits that need to be encoded into base64; if bitstogo != 0 then utf7mode == 1 */ while ((c = (unsigned char)*src) != '\0') { ++src; /* undo hex-encoding */ if (c == '%' && src[0] != '\0' && src[1] != '\0') { c = (hextab[(int) src[0]] << 4) | hextab[(int) src[1]]; src += 2; } /* normal character? */ if (c >= ' ' && c <= '~') { /* switch out of UTF-7 mode */ if (utf7mode) { if (bitstogo) { *dst++ = base64chars[(bitbuf << (6 - bitstogo)) & 0x3F]; } *dst++ = '-'; utf7mode = 0; bitstogo = bitbuf = 0; } *dst++ = c; /* encode '&' as '&-' */ if (c == '&') { *dst++ = '-'; } continue; } /* switch to UTF-7 mode */ if (!utf7mode) { *dst++ = '&'; utf7mode = 1; } /* Encode US-ASCII characters as themselves */ if (c < 0x80) { ucs4 = c; utf8total = 1; } else if (utf8total) { /* this is a subsequent octet of a multi-octet character */ /* save UTF8 bits into UCS4 */ ucs4 = (ucs4 << 6) | (c & 0x3FUL); if (++utf8pos < utf8total) { continue; } } else { /* this is the first octet of a multi-octet character */ utf8pos = 1; if (c < 0xE0) { utf8total = 2; ucs4 = c & 0x1F; } else if (c < 0xF0) { utf8total = 3; ucs4 = c & 0x0F; } else { /* NOTE: can't convert UTF8 sequences longer than 4 */ utf8total = 4; ucs4 = c & 0x03; } continue; } /* finished with UTF-8 character. make sure it isn't an overlong sequence. if it is, drop that character */ if ((ucs4 < 0x80 && utf8total > 1) || (ucs4 < 0x0800 && utf8total > 2) || (ucs4 < 0x00010000 && utf8total > 3) || (ucs4 < 0x00200000 && utf8total > 4) || (ucs4 < 0x04000000 && utf8total > 5) || (ucs4 < 0x80000000 && utf8total > 6)) { utf8total = 0; continue; } utf8total = 0; /* loop to split ucs4 into two utf16 chars if necessary */ do { if (ucs4 >= UTF16BASE) { ucs4 -= UTF16BASE; bitbuf = (bitbuf << 16) | ((ucs4 >> UTF16SHIFT) + UTF16HIGHSTART); ucs4 = (ucs4 & UTF16MASK) + UTF16LOSTART; utf16flag = 1; } else { bitbuf = (bitbuf << 16) | ucs4; utf16flag = 0; } bitstogo += 16; /* spew out base64 */ while (bitstogo >= 6) { bitstogo -= 6; *dst++ = base64chars[(bitstogo ? (bitbuf >> bitstogo) : bitbuf) & 0x3F]; } } while (utf16flag); } /* if in UTF-7 mode, finish in ASCII */ if (utf7mode) { if (bitstogo) { *dst++ = base64chars[(bitbuf << (6 - bitstogo)) & 0x3F]; } *dst++ = '-'; } /* tie off string */ *dst = '\0'; } void imapurl_fromURL(char *server, char *mailbox, const char *src) { if (server) server[0] = '\0'; if (mailbox) mailbox[0] = '\0'; if (src[0] == '{') { /* c-client style */ char *se; src++; se = strchr(src, '}'); if (se == NULL) return; if (server) { strncpy(server, src, se - src); server[se - src] = '\0'; } se += 1; if (mailbox) strcpy(mailbox, se); } else if (!strncmp(src, "imap://", 7)) { /* IMAP URL */ char *se; char *at; src += 7; /* skip imap:// */ se = strchr(src, '/'); if (se == NULL) return; at = strchr(src, '@'); if (at) { /* xxx we discard the username for now */ src = at + 1; } *se = '\0'; if (server) { strncpy(server, src, se - src); server[se - src] = '\0'; } se += 1; if (mailbox) URLtoMailbox(mailbox, se); } } void imapurl_toURL(char *dst, const char *server, const char *mailbox, const char *mechname) { if(mechname) sprintf(dst, "imap://;AUTH=%s@%s/",mechname,server); else sprintf(dst, "imap://%s/", server); MailboxToURL(dst + strlen(dst), mailbox); }