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Diffstat (limited to 'cpukit/httpd/base64.c')
| -rw-r--r-- | cpukit/httpd/base64.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/cpukit/httpd/base64.c b/cpukit/httpd/base64.c new file mode 100644 index 0000000000..b1eb6b01c5 --- /dev/null +++ b/cpukit/httpd/base64.c @@ -0,0 +1,147 @@ +/* + * base64.c -- Base64 Mime encoding + * + * Copyright (c) GoAhead Software Inc., 1995-2000. All Rights Reserved. + * + * See the file "license.txt" for usage and redistribution license requirements + */ + +/******************************** Description *********************************/ + +/* + * The base64 command encodes and decodes a string in mime base64 format + */ + +/********************************* Includes ***********************************/ + +#include "wsIntrn.h" + +/******************************** Local Data **********************************/ +/* + * Mapping of ANSI chars to base64 Mime encoding alphabet (see below) + */ + +static char_t map64[] = { + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, + -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, + 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, + -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, + 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, +}; + +static char_t alphabet64[] = { + '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', '+', '/', +}; + +/*********************************** Code *************************************/ +/* + * Decode a buffer from "string" and into "outbuf" + */ + +int websDecode64(char_t *outbuf, char_t *string, int outlen) +{ + unsigned long shiftbuf; + char_t *cp, *op; + int c, i, j, shift; + + op = outbuf; + *op = '\0'; + cp = string; + while (*cp && *cp != '=') { +/* + * Map 4 (6bit) input bytes and store in a single long (shiftbuf) + */ + shiftbuf = 0; + shift = 18; + for (i = 0; i < 4 && *cp && *cp != '='; i++, cp++) { + c = map64[*cp & 0xff]; + if (c == -1) { + error(E_L, E_LOG, T("Bad string: %s at %c index %d"), string, + c, i); + return -1; + } + shiftbuf = shiftbuf | (c << shift); + shift -= 6; + } +/* + * Interpret as 3 normal 8 bit bytes (fill in reverse order). + * Check for potential buffer overflow before filling. + */ + --i; + if ((op + i) >= &outbuf[outlen]) { + gstrcpy(outbuf, T("String too big")); + return -1; + } + for (j = 0; j < i; j++) { + *op++ = (char_t) ((shiftbuf >> (8 * (2 - j))) & 0xff); + } + *op = '\0'; + } + return 0; +} + + +/******************************************************************************/ +/* + * Encode a buffer from "string" into "outbuf" + */ + +void websEncode64(char_t *outbuf, char_t *string, int outlen) +{ + unsigned long shiftbuf; + char_t *cp, *op; + int x, i, j, shift; + + op = outbuf; + *op = '\0'; + cp = string; + while (*cp) { +/* + * Take three characters and create a 24 bit number in shiftbuf + */ + shiftbuf = 0; + for (j = 2; j >= 0 && *cp; j--, cp++) { + shiftbuf |= ((*cp & 0xff) << (j * 8)); + } +/* + * Now convert shiftbuf to 4 base64 letters. The i,j magic calculates + * how many letters need to be output. + */ + shift = 18; + for (i = ++j; i < 4 && op < &outbuf[outlen] ; i++) { + x = (shiftbuf >> shift) & 0x3f; + *op++ = alphabet64[(shiftbuf >> shift) & 0x3f]; + shift -= 6; + } +/* + * Pad at the end with '=' + */ + while (j-- > 0) { + *op++ = '='; + } + *op = '\0'; + } +} +/******************************************************************************/ |