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Diffstat (limited to 'jni/iodine/src/base32.c')
-rw-r--r-- | jni/iodine/src/base32.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/jni/iodine/src/base32.c b/jni/iodine/src/base32.c new file mode 100644 index 0000000..8731a92 --- /dev/null +++ b/jni/iodine/src/base32.c @@ -0,0 +1,270 @@ +/* + * Copyright (c) 2006-2009 Bjorn Andersson <flex@kryo.se>, Erik Ekman <yarrick@kryo.se> + * Mostly rewritten 2009 J.A.Bezemer@opensourcepartners.nl + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, 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. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "encoding.h" +#include "base32.h" + +#define BLKSIZE_RAW 5 +#define BLKSIZE_ENC 8 + +static const char cb32[] = + "abcdefghijklmnopqrstuvwxyz012345"; +static const char cb32_ucase[] = + "ABCDEFGHIJKLMNOPQRSTUVWXYZ012345"; +static unsigned char rev32[256]; +static int reverse_init = 0; + +static int base32_encode(char *, size_t *, const void *, size_t); +static int base32_decode(void *, size_t *, const char *, size_t); +static int base32_handles_dots(); +static int base32_blksize_raw(); +static int base32_blksize_enc(); + +static struct encoder base32_encoder = +{ + "Base32", + base32_encode, + base32_decode, + base32_handles_dots, + base32_handles_dots, + base32_blksize_raw, + base32_blksize_enc +}; + +struct encoder +*get_base32_encoder() +{ + return &base32_encoder; +} + +static int +base32_handles_dots() +{ + return 0; +} + +static int +base32_blksize_raw() +{ + return BLKSIZE_RAW; +} + +static int +base32_blksize_enc() +{ + return BLKSIZE_ENC; +} + +inline static void +base32_reverse_init() +{ + int i; + unsigned char c; + + if (!reverse_init) { + memset (rev32, 0, 256); + for (i = 0; i < 32; i++) { + c = cb32[i]; + rev32[(int) c] = i; + c = cb32_ucase[i]; + rev32[(int) c] = i; + } + reverse_init = 1; + } +} + +int +b32_5to8(int in) +{ + return cb32[in & 31]; +} + +int +b32_8to5(int in) +{ + base32_reverse_init(); + return rev32[in]; +} + +static int +base32_encode(char *buf, size_t *buflen, const void *data, size_t size) +/* + * Fills *buf with max. *buflen characters, encoding size bytes of *data. + * + * NOTE: *buf space should be at least 1 byte _more_ than *buflen + * to hold the trailing '\0'. + * + * return value : #bytes filled in buf (excluding \0) + * sets *buflen to : #bytes encoded from data + */ +{ + unsigned char *udata = (unsigned char *) data; + int iout = 0; /* to-be-filled output char */ + int iin = 0; /* one more than last input byte that can be + successfully decoded */ + + /* Note: Don't bother to optimize manually. GCC optimizes + better(!) when using simplistic array indexing. */ + + while (1) { + if (iout >= *buflen || iin >= size) + break; + buf[iout] = cb32[((udata[iin] & 0xf8) >> 3)]; + iout++; + + if (iout >= *buflen || iin >= size) { + iout--; /* previous char is useless */ + break; + } + buf[iout] = cb32[((udata[iin] & 0x07) << 2) | + ((iin + 1 < size) ? + ((udata[iin + 1] & 0xc0) >> 6) : 0)]; + iin++; /* 0 complete, iin=1 */ + iout++; + + if (iout >= *buflen || iin >= size) + break; + buf[iout] = cb32[((udata[iin] & 0x3e) >> 1)]; + iout++; + + if (iout >= *buflen || iin >= size) { + iout--; /* previous char is useless */ + break; + } + buf[iout] = cb32[((udata[iin] & 0x01) << 4) | + ((iin + 1 < size) ? + ((udata[iin + 1] & 0xf0) >> 4) : 0)]; + iin++; /* 1 complete, iin=2 */ + iout++; + + if (iout >= *buflen || iin >= size) + break; + buf[iout] = cb32[((udata[iin] & 0x0f) << 1) | + ((iin + 1 < size) ? + ((udata[iin + 1] & 0x80) >> 7) : 0)]; + iin++; /* 2 complete, iin=3 */ + iout++; + + if (iout >= *buflen || iin >= size) + break; + buf[iout] = cb32[((udata[iin] & 0x7c) >> 2)]; + iout++; + + if (iout >= *buflen || iin >= size) { + iout--; /* previous char is useless */ + break; + } + buf[iout] = cb32[((udata[iin] & 0x03) << 3) | + ((iin + 1 < size) ? + ((udata[iin + 1] & 0xe0) >> 5) : 0)]; + iin++; /* 3 complete, iin=4 */ + iout++; + + if (iout >= *buflen || iin >= size) + break; + buf[iout] = cb32[((udata[iin] & 0x1f))]; + iin++; /* 4 complete, iin=5 */ + iout++; + } + + buf[iout] = '\0'; + + /* store number of bytes from data that was used */ + *buflen = iin; + + return iout; +} + +#define REV32(x) rev32[(int) (x)] + +static int +base32_decode(void *buf, size_t *buflen, const char *str, size_t slen) +/* + * Fills *buf with max. *buflen bytes, decoded from slen chars in *str. + * Decoding stops early when *str contains \0. + * Illegal encoded chars are assumed to decode to zero. + * + * NOTE: *buf space should be at least 1 byte _more_ than *buflen + * to hold a trailing '\0' that is added (though *buf will usually + * contain full-binary data). + * + * return value : #bytes filled in buf (excluding \0) + */ +{ + unsigned char *ubuf = (unsigned char *) buf; + int iout = 0; /* to-be-filled output byte */ + int iin = 0; /* next input char to use in decoding */ + + base32_reverse_init (); + + /* Note: Don't bother to optimize manually. GCC optimizes + better(!) when using simplistic array indexing. */ + + while (1) { + if (iout >= *buflen || iin + 1 >= slen || + str[iin] == '\0' || str[iin + 1] == '\0') + break; + ubuf[iout] = ((REV32(str[iin]) & 0x1f) << 3) | + ((REV32(str[iin + 1]) & 0x1c) >> 2); + iin++; /* 0 used up, iin=1 */ + iout++; + + if (iout >= *buflen || iin + 2 >= slen || + str[iin] == '\0' || str[iin + 1] == '\0' || + str[iin + 2] == '\0') + break; + ubuf[iout] = ((REV32(str[iin]) & 0x03) << 6) | + ((REV32(str[iin + 1]) & 0x1f) << 1) | + ((REV32(str[iin + 2]) & 0x10) >> 4); + iin += 2; /* 1,2 used up, iin=3 */ + iout++; + + if (iout >= *buflen || iin + 1 >= slen || + str[iin] == '\0' || str[iin + 1] == '\0') + break; + ubuf[iout] = ((REV32(str[iin]) & 0x0f) << 4) | + ((REV32(str[iin + 1]) & 0x1e) >> 1); + iin++; /* 3 used up, iin=4 */ + iout++; + + if (iout >= *buflen || iin + 2 >= slen || + str[iin] == '\0' || str[iin + 1] == '\0' || + str[iin + 2] == '\0') + break; + ubuf[iout] = ((REV32(str[iin]) & 0x01) << 7) | + ((REV32(str[iin + 1]) & 0x1f) << 2) | + ((REV32(str[iin + 2]) & 0x18) >> 3); + iin += 2; /* 4,5 used up, iin=6 */ + iout++; + + if (iout >= *buflen || iin + 1 >= slen || + str[iin] == '\0' || str[iin + 1] == '\0') + break; + ubuf[iout] = ((REV32(str[iin]) & 0x07) << 5) | + ((REV32(str[iin + 1]) & 0x1f)); + iin += 2; /* 6,7 used up, iin=8 */ + iout++; + } + + ubuf[iout] = '\0'; + + return iout; +} |