/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */ /* * Authors: Jeffrey Stedfast * * Copyright 2002 Ximian, Inc. (www.ximian.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA. * */ #ifdef HAVE_CONFIG_H #include #endif #include #include "gmime-filter-yenc.h" static void filter_destroy (GMimeFilter *filter); static GMimeFilter *filter_copy (GMimeFilter *filter); static void filter_filter (GMimeFilter *filter, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace); static void filter_complete (GMimeFilter *filter, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace); static void filter_reset (GMimeFilter *filter); static GMimeFilter filter_template = { NULL, NULL, NULL, NULL, 0, 0, NULL, 0, 0, filter_destroy, filter_copy, filter_filter, filter_complete, filter_reset, }; /** * g_mime_filter_yenc_new: * @direction: encode direction * * Creates a new yEnc filter. * * Returns a new yEnc filter. **/ GMimeFilter * g_mime_filter_yenc_new (GMimeFilterYencDirection direction) { GMimeFilterYenc *new; new = g_new (GMimeFilterYenc, 1); new->direction = direction; new->part = 0; new->pcrc = GMIME_YENCODE_CRC_INIT; new->crc = GMIME_YENCODE_CRC_INIT; switch (direction) { case GMIME_FILTER_YENC_DIRECTION_ENCODE: new->state = GMIME_YENCODE_STATE_INIT; break; case GMIME_FILTER_YENC_DIRECTION_DECODE: new->state = GMIME_YDECODE_STATE_INIT; break; default: g_assert_not_reached (); } g_mime_filter_construct (GMIME_FILTER (new), &filter_template); return GMIME_FILTER (new); } /** * g_mime_filter_yenc_set_state: * @yenc: yEnc filter * @state: encode/decode state * * Sets the current state of the yencoder/ydecoder **/ void g_mime_filter_yenc_set_state (GMimeFilterYenc *yenc, int state) { g_return_if_fail (yenc != NULL); yenc->state = state; } /** * g_mime_filter_yenc_set_crc: * @yenc: yEnc filter * @crc: crc32 * * Sets the current crc32 value on the yEnc filter @yenc to @crc. **/ void g_mime_filter_yenc_set_crc (GMimeFilterYenc *yenc, guint32 crc) { g_return_if_fail (yenc != NULL); yenc->crc = crc; } #if 0 /* FIXME: once we parse out the yenc part id, we can re-enable this interface */ /** * g_mime_filter_yenc_get_part: * @yenc: yEnc filter * * Gets the part id of the current decoded yEnc stream or -1 on fail. * * Returns the part id of the current decoded yEnc stream or -1 on * fail. **/ int g_mime_filter_yenc_get_part (GMimeFilterYenc *yenc) { g_return_val_if_fail (yenc != NULL, -1); if (yenc->state & GMIME_YDECODE_STATE_PART) return yenc->part; return -1; } #endif /** * g_mime_filter_yenc_get_pcrc: * @yenc: yEnc filter * * Get the computed part crc or (guint32) -1 on fail. * * Returns the computed part crc or (guint32) -1 on fail. **/ guint32 g_mime_filter_yenc_get_pcrc (GMimeFilterYenc *yenc) { g_return_val_if_fail (yenc != NULL, -1); return GMIME_YENCODE_CRC_FINAL (yenc->pcrc); } /** * g_mime_filter_yenc_get_crc: * @yenc: yEnc filter * * Get the computed crc or (guint32) -1 on fail. * * Returns the computed crc or (guint32) -1 on fail. **/ guint32 g_mime_filter_yenc_get_crc (GMimeFilterYenc *yenc) { g_return_val_if_fail (yenc != NULL, -1); return GMIME_YENCODE_CRC_FINAL (yenc->crc); } static void filter_destroy (GMimeFilter *filter) { g_free (filter); } static GMimeFilter * filter_copy (GMimeFilter *filter) { GMimeFilterYenc *yenc = (GMimeFilterYenc *) filter; return g_mime_filter_yenc_new (yenc->direction); } /* here we do all of the basic yEnc filtering */ static void filter_filter (GMimeFilter *filter, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace) { GMimeFilterYenc *yenc = (GMimeFilterYenc *) filter; size_t newlen = 0; switch (yenc->direction) { case GMIME_FILTER_YENC_DIRECTION_ENCODE: /* won't go to more than 2 * (x + 2) + 62 */ g_mime_filter_set_size (filter, (len + 2) * 2 + 62, FALSE); newlen = g_mime_yencode_step (in, len, filter->outbuf, ¥c->state, ¥c->pcrc, ¥c->crc); g_assert (newlen <= (len + 2) * 2 + 62); break; case GMIME_FILTER_YENC_DIRECTION_DECODE: if (!(yenc->state & GMIME_YDECODE_STATE_DECODE)) { register char *inptr, *inend; size_t left; inptr = in; inend = inptr + len; /* we cannot start decoding until we have found an =ybegin line */ if (!(yenc->state & GMIME_YDECODE_STATE_BEGIN)) { while (inptr < inend) { left = inend - inptr; if (left < 8) { if (!strncmp (inptr, "=ybegin ", left)) g_mime_filter_backup (filter, inptr, left); break; } else if (!strncmp (inptr, "=ybegin ", 8)) { for (in = inptr; inptr < inend && *inptr != '\n'; inptr++); if (inptr < inend) { inptr++; yenc->state |= GMIME_YDECODE_STATE_BEGIN; /* we can start ydecoding if the next line isn't a ypart... */ in = inptr; len = inend - in; } else { /* we don't have enough... */ g_mime_filter_backup (filter, in, left); } break; } /* go to the next line */ for ( ; inptr < inend && *inptr != '\n'; inptr++); if (inptr < inend) inptr++; } } left = inend - inptr; if ((yenc->state & GMIME_YDECODE_STATE_BEGIN) && left > 0) { /* we have found an '=ybegin' line but we may yet have an "=ypart" line to yield before decoding the content */ if (left < 7 && !strncmp (inptr, "=ypart ", left)) { g_mime_filter_backup (filter, inptr, left); } else if (!strncmp (inptr, "=ypart ", 7)) { for (in = inptr; inptr < inend && *inptr != '\n'; inptr++); if (inptr < inend) { inptr++; yenc->state |= GMIME_YDECODE_STATE_PART | GMIME_YDECODE_STATE_DECODE; in = inptr; len = inend - in; } else { g_mime_filter_backup (filter, in, left); } } else { /* guess it doesn't have a =ypart line */ yenc->state |= GMIME_YDECODE_STATE_DECODE; } } } if ((yenc->state & GMIME_YDECODE_STATE_DECODE) && !(yenc->state & GMIME_YDECODE_STATE_END)) { /* all yEnc headers have been found so we can now start decoding */ g_mime_filter_set_size (filter, len + 3, FALSE); newlen = g_mime_ydecode_step (in, len, filter->outbuf, ¥c->state, ¥c->pcrc, ¥c->crc); g_assert (newlen <= len + 3); } else { newlen = 0; } break; } *out = filter->outbuf; *outlen = newlen; *outprespace = filter->outpre; } static void filter_complete (GMimeFilter *filter, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace) { GMimeFilterYenc *yenc = (GMimeFilterYenc *) filter; size_t newlen = 0; switch (yenc->direction) { case GMIME_FILTER_YENC_DIRECTION_ENCODE: /* won't go to more than 2 * (x + 2) + 62 */ g_mime_filter_set_size (filter, (len + 2) * 2 + 62, FALSE); newlen = g_mime_yencode_close (in, len, filter->outbuf, ¥c->state, ¥c->pcrc, ¥c->crc); g_assert (newlen <= (len + 2) * 2 + 62); break; case GMIME_FILTER_YENC_DIRECTION_DECODE: if ((yenc->state & GMIME_YDECODE_STATE_DECODE) && !(yenc->state & GMIME_YDECODE_STATE_END)) { /* all yEnc headers have been found so we can now start decoding */ g_mime_filter_set_size (filter, len + 3, FALSE); newlen = g_mime_ydecode_step (in, len, filter->outbuf, ¥c->state, ¥c->pcrc, ¥c->crc); g_assert (newlen <= len + 3); } else { newlen = 0; } break; } *out = filter->outbuf; *outlen = newlen; *outprespace = filter->outpre; } /* should this 'flush' outstanding state/data bytes? */ static void filter_reset (GMimeFilter *filter) { GMimeFilterYenc *yenc = (GMimeFilterYenc *) filter; switch (yenc->direction) { case GMIME_FILTER_YENC_DIRECTION_ENCODE: yenc->state = GMIME_YENCODE_STATE_INIT; break; case GMIME_FILTER_YENC_DIRECTION_DECODE: yenc->state = GMIME_YDECODE_STATE_INIT; break; } yenc->pcrc = GMIME_YENCODE_CRC_INIT; yenc->crc = GMIME_YENCODE_CRC_INIT; } static const int yenc_crc_table[256] = { 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d }; #define yenc_crc_add(crc, c) (yenc_crc_table[(((int) (crc)) ^ ((unsigned char) (c))) & 0xff] ^ ((((int) (crc)) >> 8) & 0x00ffffff)) #define YENC_NEWLINE_ESCAPE (GMIME_YDECODE_STATE_EOLN | GMIME_YDECODE_STATE_ESCAPE) /** * g_mime_ydecode_step: * @in: input buffer * @inlen: input buffer length * @out: output buffer * @state: ydecode state * @pcrc: part crc state * @crc: crc state * * Performs a 'decode step' on a chunk of yEncoded data of length * @inlen pointed to by @in and writes to @out. Assumes the =ybegin * and =ypart lines have already been stripped off. * * To get the crc32 value of the part, use GMIME_YENCODE_CRC_FINAL * (@pcrc). If there are more parts, you should reuse @crc without * re-initializing. Once all parts have been decoded, you may get the * combined crc32 value of all the parts using GMIME_YENCODE_CRC_FINAL * (@crc). * * Returns the number of bytes decoded. **/ size_t g_mime_ydecode_step (const unsigned char *in, size_t inlen, unsigned char *out, int *state, guint32 *pcrc, guint32 *crc) { const register unsigned char *inptr; register unsigned char *outptr; const unsigned char *inend; unsigned char ch; int ystate; if (*state & GMIME_YDECODE_STATE_END) return 0; ystate = *state; inend = in + inlen; outptr = out; inptr = in; while (inptr < inend) { ch = *inptr++; if ((ystate & YENC_NEWLINE_ESCAPE) == YENC_NEWLINE_ESCAPE) { ystate &= ~GMIME_YDECODE_STATE_EOLN; if (ch == 'y') { /* we probably have a =yend here */ ystate |= GMIME_YDECODE_STATE_END; break; } } if (ch == '\n') { ystate |= GMIME_YDECODE_STATE_EOLN; continue; } if (ystate & GMIME_YDECODE_STATE_ESCAPE) { ystate &= ~GMIME_YDECODE_STATE_ESCAPE; ch -= 64; } else if (ch == '=') { ystate |= GMIME_YDECODE_STATE_ESCAPE; continue; } ystate &= ~GMIME_YDECODE_STATE_EOLN; *outptr++ = ch -= 42; *pcrc = yenc_crc_add (*pcrc, ch); *crc = yenc_crc_add (*crc, ch); } *state = ystate; return outptr - out; } /** * g_mime_yencode_step: * @in: input buffer * @inlen: input buffer length * @out: output buffer * @state: yencode state * @pcrc: part crc state * @crc: crc state * * Performs an yEncode 'encode step' on a chunk of raw data of length * @inlen pointed to by @in and writes to @out. * * @state should be initialized to GMIME_YENCODE_STATE_INIT before * beginning making the first call to this function. Subsequent calls * should reuse @state. * * Along the same lines, @pcrc and @crc should be initialized to * GMIME_YENCODE_CRC_INIT before using. * * Returns the number of bytes encoded. **/ size_t g_mime_yencode_step (const unsigned char *in, size_t inlen, unsigned char *out, int *state, guint32 *pcrc, guint32 *crc) { const register unsigned char *inptr; register unsigned char *outptr; const unsigned char *inend; register int already; unsigned char ch; inend = in + inlen; outptr = out; already = *state; inptr = in; while (inptr < inend) { ch = (*inptr++); *pcrc = yenc_crc_add (*pcrc, ch); *crc = yenc_crc_add (*crc, ch); ch += 42; if (ch == '\0' || ch == '\t' || ch == '\r' || ch == '\n' || ch == '=') { *outptr++ = '='; *outptr++ = ch + 64; already += 2; } else { *outptr++ = ch; already++; } if (already >= 128) { *outptr++ = '\n'; already = 0; } } *state = already; return outptr - out; } /** * g_mime_yencode_close: * @in: input buffer * @inlen: input buffer length * @out: output buffer * @state: yencode state * @pcrc: part crc state * @crc: crc state * * Call this function when finished encoding data with * g_mime_yencode_step to flush off the remaining state. * * GMIME_YENCODE_CRC_FINAL (@pcrc) will give you the crc32 of the * encoded "part". If there are more "parts" to encode, you should * re-use @crc when encoding the next "parts" and then use * GMIME_YENCODE_CRC_FINAL (@crc) to get the combined crc32 value of * all the parts. * * Returns the number of bytes encoded. **/ size_t g_mime_yencode_close (const unsigned char *in, size_t inlen, unsigned char *out, int *state, guint32 *pcrc, guint32 *crc) { register unsigned char *outptr; outptr = out; if (inlen) outptr += g_mime_yencode_step (in, inlen, out, state, pcrc, crc); if (*state) *outptr++ = '\n'; *state = GMIME_YENCODE_STATE_INIT; return outptr - out; }