diff options
Diffstat (limited to 'libbb/uuencode.c')
| -rw-r--r-- | libbb/uuencode.c | 84 |
1 files changed, 81 insertions, 3 deletions
diff --git a/libbb/uuencode.c b/libbb/uuencode.c index d36b34f63..b4ee20c20 100644 --- a/libbb/uuencode.c +++ b/libbb/uuencode.c @@ -8,7 +8,8 @@ */ #include "libbb.h" -/* Conversion table. for base 64 */ +/* Conversion tables */ +/* for base 64 */ const char bb_uuenc_tbl_base64[65 + 1] ALIGN1 = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', @@ -21,7 +22,16 @@ const char bb_uuenc_tbl_base64[65 + 1] ALIGN1 = { '=' /* termination character */, '\0' /* needed for uudecode.c only */ }; - +#if ENABLE_BASE32 +const char bb_uuenc_tbl_base32[33 + 1] ALIGN1 = { + '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', '2', '3', '4', '5', '6', '7', + '=', + '\0' +}; +#endif const char bb_uuenc_tbl_std[65] ALIGN1 = { '`', '!', '"', '#', '$', '%', '&', '\'', '(', ')', '*', '+', ',', '-', '.', '/', @@ -153,6 +163,68 @@ const char* FAST_FUNC decode_base64(char **pp_dst, const char *src) return src_tail; } +#if ENABLE_BASE32 +const char* FAST_FUNC decode_base32(char **pp_dst, const char *src) +{ + char *dst = *pp_dst; + const char *src_tail; + + while (1) { + unsigned char five_bit[8]; + int count = 0; + + /* Fetch up to eight 5-bit values */ + src_tail = src; + while (count < 8) { + char *table_ptr; + int ch; + + /* Get next _valid_ character. + * bb_uuenc_tbl_base32[] contains this string: + * 0 1 2 3 + * 01234567890123456789012345678901 + * "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567=" + */ + do { + ch = *src; + if (ch == '\0') { + if (count == 0) { + src_tail = src; + } + goto ret; + } + src++; + table_ptr = strchr(bb_uuenc_tbl_base32, toupper(ch)); + } while (!table_ptr); + + /* Convert encoded character to decimal */ + ch = table_ptr - bb_uuenc_tbl_base32; + + /* ch is 32 if char was '=', otherwise 0..31 */ + if (ch == 32) + break; + five_bit[count] = ch; + count++; + } + + /* Transform 5-bit values to 8-bit ones */ + if (count > 1) // xxxxx xxx-- ----- ----- ----- ----- ----- ----- + *dst++ = five_bit[0] << 3 | five_bit[1] >> 2; + if (count > 3) // ----- ---xx xxxxx x---- ----- ----- ----- ----- + *dst++ = five_bit[1] << 6 | five_bit[2] << 1 | five_bit[3] >> 4; + if (count > 4) // ----- ----- ----- -xxxx xxxx- ----- ----- ----- + *dst++ = five_bit[3] << 4 | five_bit[4] >> 1; + if (count > 6) // ----- ----- ----- ----- ----x xxxxx xx--- ----- + *dst++ = five_bit[4] << 7 | five_bit[5] << 2 | five_bit[6] >> 3; + if (count > 7) // ----- ----- ----- ----- ----- ----- --xxx xxxxx + *dst++ = five_bit[6] << 5 | five_bit[7]; + } /* while (1) */ + ret: + *pp_dst = dst; + return src_tail; +} +#endif + /* * Decode base64 encoded stream. * Can stop on EOF, specified char, or on uuencode-style "====" line: @@ -163,6 +235,7 @@ void FAST_FUNC read_base64(FILE *src_stream, FILE *dst_stream, int flags) /* Note that EOF _can_ be passed as exit_char too */ #define exit_char ((int)(signed char)flags) #define uu_style_end (flags & BASE64_FLAG_UU_STOP) +#define base32 (flags & BASE64_32) /* uuencoded files have 61 byte lines. Use 64 byte buffer * to process line at a time. @@ -204,7 +277,12 @@ void FAST_FUNC read_base64(FILE *src_stream, FILE *dst_stream, int flags) return; out_tail = out_buf; - in_tail = decode_base64(&out_tail, in_buf); +#if ENABLE_BASE32 + if (base32) + in_tail = decode_base32(&out_tail, in_buf); + else +#endif + in_tail = decode_base64(&out_tail, in_buf); fwrite(out_buf, (out_tail - out_buf), 1, dst_stream); |