| /** @file |
| |
| A brief file description |
| |
| @section license License |
| |
| Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you under the Apache License, Version 2.0 (the |
| "License"); you may not use this file except in compliance |
| with the License. You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| /* |
| * Base64 encoding and decoding as according to RFC1521. Similar to uudecode. |
| * |
| * RFC 1521 requires inserting line breaks for long lines. The basic web |
| * authentication scheme does not require them. This implementation is |
| * intended for web-related use, and line breaks are not implemented. |
| * |
| * These routines return char*'s to malloc-ed strings. The caller is |
| * responsible for freeing the strings. |
| */ |
| #include "tscore/ink_platform.h" |
| #include "tscore/ink_base64.h" |
| #include "tscore/ink_assert.h" |
| |
| // TODO: The code here seems a bit klunky, and could probably be improved a bit. |
| |
| bool |
| ats_base64_encode(const unsigned char *inBuffer, size_t inBufferSize, char *outBuffer, size_t outBufSize, size_t *length) |
| { |
| static const char _codes[66] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| char *obuf = outBuffer; |
| char in_tail[4]; |
| |
| if (outBufSize < ATS_BASE64_ENCODE_DSTLEN(inBufferSize)) { |
| return false; |
| } |
| |
| while (inBufferSize > 2) { |
| *obuf++ = _codes[(inBuffer[0] >> 2) & 077]; |
| *obuf++ = _codes[((inBuffer[0] & 03) << 4) | ((inBuffer[1] >> 4) & 017)]; |
| *obuf++ = _codes[((inBuffer[1] & 017) << 2) | ((inBuffer[2] >> 6) & 017)]; |
| *obuf++ = _codes[inBuffer[2] & 077]; |
| |
| inBufferSize -= 3; |
| inBuffer += 3; |
| } |
| |
| /* |
| * We've done all the input groups of three chars. We're left |
| * with 0, 1, or 2 input chars. We have to add zero-bits to the |
| * right if we don't have enough input chars. |
| * If 0 chars left, we're done. |
| * If 1 char left, form 2 output chars, and add 2 pad chars to output. |
| * If 2 chars left, form 3 output chars, add 1 pad char to output. |
| */ |
| if (inBufferSize == 0) { |
| *obuf = '\0'; |
| if (length) { |
| *length = (obuf - outBuffer); |
| } |
| } else { |
| memset(in_tail, 0, sizeof(in_tail)); |
| memcpy(in_tail, inBuffer, inBufferSize); |
| |
| *(obuf) = _codes[(in_tail[0] >> 2) & 077]; |
| *(obuf + 1) = _codes[((in_tail[0] & 03) << 4) | ((in_tail[1] >> 4) & 017)]; |
| *(obuf + 2) = _codes[((in_tail[1] & 017) << 2) | ((in_tail[2] >> 6) & 017)]; |
| *(obuf + 3) = _codes[in_tail[2] & 077]; |
| |
| if (inBufferSize == 1) { |
| *(obuf + 2) = '='; |
| } |
| *(obuf + 3) = '='; |
| *(obuf + 4) = '\0'; |
| |
| if (length) { |
| *length = (obuf + 4) - outBuffer; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool |
| ats_base64_encode(const char *inBuffer, size_t inBufferSize, char *outBuffer, size_t outBufSize, size_t *length) |
| { |
| return ats_base64_encode(reinterpret_cast<const unsigned char *>(inBuffer), inBufferSize, outBuffer, outBufSize, length); |
| } |
| |
| /*------------------------------------------------------------------------- |
| This is a reentrant, and malloc free implementation of ats_base64_decode. |
| -------------------------------------------------------------------------*/ |
| #ifdef DECODE |
| #undef DECODE |
| #endif |
| |
| #define DECODE(x) printableToSixBit[(unsigned char)x] |
| #define MAX_PRINT_VAL 63 |
| |
| /* Converts a printable character to it's six bit representation */ |
| const unsigned char printableToSixBit[256] = { |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 62, 64, 62, 64, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, 64, 64, 64, 64, 64, |
| 64, 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, 64, 64, 64, 64, 63, |
| 64, 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, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, |
| 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64}; |
| |
| bool |
| ats_base64_decode(const char *inBuffer, size_t inBufferSize, unsigned char *outBuffer, size_t outBufSize, size_t *length) |
| { |
| size_t inBytes = 0; |
| size_t decodedBytes = 0; |
| unsigned char *buf = outBuffer; |
| int inputBytesDecoded = 0; |
| |
| // Make sure there is sufficient space in the output buffer |
| if (outBufSize < ATS_BASE64_DECODE_DSTLEN(inBufferSize)) { |
| return false; |
| } |
| |
| // Ignore any trailing ='s or other undecodable characters. |
| // TODO: Perhaps that ought to be an error instead? |
| while (inBytes < inBufferSize && printableToSixBit[static_cast<uint8_t>(inBuffer[inBytes])] <= MAX_PRINT_VAL) { |
| ++inBytes; |
| } |
| |
| for (size_t i = 0; i < inBytes; i += 4) { |
| buf[0] = static_cast<unsigned char>(DECODE(inBuffer[0]) << 2 | DECODE(inBuffer[1]) >> 4); |
| buf[1] = static_cast<unsigned char>(DECODE(inBuffer[1]) << 4 | DECODE(inBuffer[2]) >> 2); |
| buf[2] = static_cast<unsigned char>(DECODE(inBuffer[2]) << 6 | DECODE(inBuffer[3])); |
| |
| buf += 3; |
| inBuffer += 4; |
| decodedBytes += 3; |
| inputBytesDecoded += 4; |
| } |
| |
| // Check to see if we decoded a multiple of 4 four |
| // bytes |
| if ((inBytes - inputBytesDecoded) & 0x3) { |
| if (DECODE(inBuffer[-2]) > MAX_PRINT_VAL) { |
| decodedBytes -= 2; |
| } else { |
| decodedBytes -= 1; |
| } |
| } |
| outBuffer[decodedBytes] = '\0'; |
| |
| if (length) { |
| *length = decodedBytes; |
| } |
| |
| return true; |
| } |