/* This file was derived from the libwww code, version 2.15, from CERN. A number of modifications have been made by Spyglass. eric@spyglass.com This file was removed from LibWWW and placed into the Security Protocol Module. jeff@spyglass.com */ /* MODULE HTUU.c ** UUENCODE AND UUDECODE ** ** ACKNOWLEDGEMENT: ** This code is taken from rpem distribution, and was originally ** written by Mark Riordan. ** ** AUTHORS: ** MR Mark Riordan riordanmr@clvax1.cl.msu.edu ** AL Ari Luotonen luotonen@dxcern.cern.ch ** ** HISTORY: ** Added as part of the WWW library and edited to conform ** with the WWW project coding standards by: AL 5 Aug 1993 ** Originally written by: MR 12 Aug 1990 ** Original header text: ** ------------------------------------------------------------- ** File containing routines to convert a buffer ** of bytes to/from RFC 1113 printable encoding format. ** ** This technique is similar to the familiar Unix uuencode ** format in that it maps 6 binary bits to one ASCII ** character (or more aptly, 3 binary bytes to 4 ASCII ** characters). However, RFC 1113 does not use the same ** mapping to printable characters as uuencode. ** ** Mark Riordan 12 August 1990 and 17 Feb 1991. ** This code is hereby placed in the public domain. ** ------------------------------------------------------------- ** ** BUGS: ** ** */ #define MAXCODE 64 static const char six2pr[MAXCODE] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' }; static unsigned char pr2six[256]; /*--- function HTUU_encode ----------------------------------------------- * * Encode a single line of binary data to a standard format that * uses only printing ASCII characters (but takes up 33% more bytes). * * Entry bufin points to a buffer of bytes. * nbytes is the number of bytes in that buffer. * This cannot be more than 48. * bufcoded points to an output buffer. Be sure that this * can hold at least 1 + 4*(nbytes+2)/3 characters. * outbufsize is the maximum number of bytes that * can fit in bufcoded. * * Exit bufcoded contains the coded line. The first 4*(nbytes+2)/3 * bytes contain printing ASCII characters representing * those binary bytes. This may include one or two '=' * characters used as padding at the end. The last * byte is a zero byte. * * Returns the number of ASCII characters in bufcoded or -1 in * the case of overflow. */ int HTUU_encode(unsigned char *bufin, int nbytes, char *bufout, int bufoutsize) { /* ENC is the basic 1 character encoding function to make a char printing */ #define ENC(c) six2pr[c] char *bufcoded = bufout; while (nbytes > 0) { if (bufoutsize < 4) return (-1); *(bufout++) = ENC(*bufin >> 2); *(bufout++) = nbytes > 1 ? ENC((*bufin << 4) & 060 | (bufin[1] >> 4) & 017) : ENC((*bufin << 4) & 060); *(bufout++) = nbytes > 2 ? ENC((bufin[1] << 2) & 074 | (bufin[2] >> 6) & 03) : nbytes > 1 ? ENC((bufin[1] << 2) & 074) : '='; *(bufout++) = nbytes > 2 ? ENC(bufin[2] & 077) : '='; bufoutsize -= 4; bufin += 3; nbytes -= 3; } if (bufoutsize > 0) *bufout = '\0'; return (int)(bufout - bufcoded); } /*--- function HTUU_decode ------------------------------------------------ * * Decode an ASCII-encoded buffer back to its original binary form. * * Entry bufcoded points to a uuencoded string. It is * terminated by any character not in * the printable character table six2pr, but * leading whitespace is stripped. * bufplain points to the output buffer; must be big * enough to hold the decoded string (generally * shorter than the encoded string) plus * as many as two extra bytes used during * the decoding process. * outbufsize is the maximum number of bytes that * can fit in bufplain. * * Exit Returns the number of binary bytes decoded. * bufplain contains these bytes. */ int HTUU_decode(char *bufin, unsigned char *bufout, int bufoutsize) { /* single character decode */ #define DEC(c) pr2six[(unsigned char) c] static int first = 1; int nbytesdecoded = 0, nbytes; unsigned char c, *pc; /* If this is the first call, initialize the mapping table. * This code should work even on non-ASCII machines. */ if (first) { first = 0; memset(pr2six, MAXCODE, sizeof(pr2six)); for (c = 0; c < MAXCODE; c++) DEC(six2pr[c]) = c; #if 0 pr2six['A'] = 0; pr2six['B'] = 1; pr2six['C'] = 2; pr2six['D'] = 3; pr2six['E'] = 4; pr2six['F'] = 5; pr2six['G'] = 6; pr2six['H'] = 7; pr2six['I'] = 8; pr2six['J'] = 9; pr2six['K'] = 10; pr2six['L'] = 11; pr2six['M'] = 12; pr2six['N'] = 13; pr2six['O'] = 14; pr2six['P'] = 15; pr2six['Q'] = 16; pr2six['R'] = 17; pr2six['S'] = 18; pr2six['T'] = 19; pr2six['U'] = 20; pr2six['V'] = 21; pr2six['W'] = 22; pr2six['X'] = 23; pr2six['Y'] = 24; pr2six['Z'] = 25; pr2six['a'] = 26; pr2six['b'] = 27; pr2six['c'] = 28; pr2six['d'] = 29; pr2six['e'] = 30; pr2six['f'] = 31; pr2six['g'] = 32; pr2six['h'] = 33; pr2six['i'] = 34; pr2six['j'] = 35; pr2six['k'] = 36; pr2six['l'] = 37; pr2six['m'] = 38; pr2six['n'] = 39; pr2six['o'] = 40; pr2six['p'] = 41; pr2six['q'] = 42; pr2six['r'] = 43; pr2six['s'] = 44; pr2six['t'] = 45; pr2six['u'] = 46; pr2six['v'] = 47; pr2six['w'] = 48; pr2six['x'] = 49; pr2six['y'] = 50; pr2six['z'] = 51; pr2six['0'] = 52; pr2six['1'] = 53; pr2six['2'] = 54; pr2six['3'] = 55; pr2six['4'] = 56; pr2six['5'] = 57; pr2six['6'] = 58; pr2six['7'] = 59; pr2six['8'] = 60; pr2six['9'] = 61; pr2six['+'] = 62; pr2six['/'] = 63; #endif } /* Strip leading whitespace. */ while (*bufin == ' ' || *bufin == '\t') bufin++; /* Figure out how many characters are in the input buffer. */ for (pc = (unsigned char*)bufin; DEC(*pc) < MAXCODE; pc++); nbytes = (int)(pc - (unsigned char*)bufin); while (nbytes > 1) { if (bufoutsize < 3) return nbytesdecoded; *(bufout++) = DEC(*bufin) << 2 | DEC(bufin[1]) >> 4; *(bufout++) = DEC(bufin[1]) << 4 | DEC(bufin[2]) >> 2; *(bufout++) = nbytes > 2 ? (DEC(bufin[2]) << 6 | DEC(bufin[3])) : 0; bufoutsize -= 3; bufin += 4; nbytes -= 4; nbytesdecoded += 3; } if (nbytes < 0) nbytesdecoded += nbytes; return nbytesdecoded; }