| /* |
| * This file is based on roken from the FreeBSD source. It has been modified |
| * to not use malloc() and instead expect static buffers, and tabs have been |
| * replaced with spaces. Also, instead of strlen() on the resulting string, |
| * pointer arithmitic is done, as p represents the end of the buffer. |
| */ |
| |
| /* |
| * Copyright (c) 1995-2001 Kungliga Tekniska Högskolan |
| * (Royal Institute of Technology, Stockholm, Sweden). |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * 3. Neither the name of the Institute nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <stdlib.h> |
| #include <string.h> |
| #include <limits.h> |
| #include <stdio.h> |
| |
| #include <os/mynewt.h> |
| #include <base64/base64.h> |
| |
| static const char base64_chars[] = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| |
| static int |
| pos(char c) |
| { |
| const char *p; |
| for (p = base64_chars; *p; p++) |
| if (*p == c) |
| return p - base64_chars; |
| return -1; |
| } |
| |
| int |
| base64_encode(const void *data, int size, char *s, uint8_t should_pad) |
| { |
| char *p; |
| int i; |
| int c; |
| const unsigned char *q; |
| char *last; |
| int diff; |
| |
| p = s; |
| |
| q = (const unsigned char *) data; |
| last = NULL; |
| i = 0; |
| while (i < size) { |
| c = q[i++]; |
| c *= 256; |
| if (i < size) |
| c += q[i]; |
| i++; |
| c *= 256; |
| if (i < size) |
| c += q[i]; |
| i++; |
| p[0] = base64_chars[(c & 0x00fc0000) >> 18]; |
| p[1] = base64_chars[(c & 0x0003f000) >> 12]; |
| p[2] = base64_chars[(c & 0x00000fc0) >> 6]; |
| p[3] = base64_chars[(c & 0x0000003f) >> 0]; |
| last = p; |
| p += 4; |
| } |
| |
| if (last) { |
| diff = i - size; |
| if (diff > 0) { |
| if (should_pad) { |
| memset(last + (4 - diff), '=', diff); |
| } else { |
| p = last + (4 - diff); |
| } |
| } |
| } |
| |
| *p = 0; |
| |
| return (p - s); |
| } |
| |
| int |
| base64_pad(char *buf, int len) |
| { |
| int remainder; |
| |
| remainder = len % 4; |
| if (remainder == 0) { |
| return (0); |
| } |
| |
| memset(buf, '=', 4 - remainder); |
| |
| return (4 - remainder); |
| } |
| |
| #define DECODE_ERROR -1 |
| |
| static unsigned int |
| token_decode(const char *token, int len) |
| { |
| int i; |
| unsigned int val = 0; |
| int marker = 0; |
| |
| if (len < 4) { |
| return DECODE_ERROR; |
| } |
| |
| for (i = 0; i < 4; i++) { |
| val *= 64; |
| if (token[i] == '=') { |
| marker++; |
| } else if (marker > 0) { |
| return DECODE_ERROR; |
| } else { |
| val += pos(token[i]); |
| } |
| } |
| |
| if (marker > 2) { |
| return DECODE_ERROR; |
| } |
| |
| return (marker << 24) | val; |
| } |
| |
| int |
| base64_decode(const char *str, void *data) |
| { |
| struct base64_decoder dec = { |
| .src = str, |
| .dst = data, |
| }; |
| |
| return base64_decoder_go(&dec); |
| } |
| |
| int |
| base64_decode_maxlen(const char *str, void *data, int len) |
| { |
| struct base64_decoder dec = { |
| .src = str, |
| .dst = data, |
| .dst_len = len, |
| }; |
| |
| return base64_decoder_go(&dec); |
| } |
| |
| int |
| base64_decode_len(const char *str) |
| { |
| int len; |
| |
| len = strlen(str); |
| while (len && str[len - 1] == '=') { |
| len--; |
| } |
| return len * 3 / 4; |
| } |
| |
| int |
| base64_decoder_go(struct base64_decoder *dec) |
| { |
| unsigned int marker; |
| unsigned int val; |
| uint8_t *dst; |
| char sval; |
| int read_len; |
| int src_len; |
| int src_rem; |
| int src_off; |
| int dst_len; |
| int dst_off; |
| int i; |
| |
| dst = dec->dst; |
| dst_off = 0; |
| src_off = 0; |
| |
| /* A length <= 0 means "unbounded". */ |
| if (dec->src_len <= 0) { |
| src_len = INT_MAX; |
| } else { |
| src_len = dec->src_len; |
| } |
| if (dec->dst_len <= 0) { |
| dst_len = INT_MAX; |
| } else { |
| dst_len = dec->dst_len; |
| } |
| |
| while (1) { |
| src_rem = src_len - src_off; |
| if (src_rem == 0) { |
| /* End of source input. */ |
| break; |
| } |
| |
| if (dec->src[src_off] == '\0') { |
| /* End of source string. */ |
| break; |
| } |
| |
| /* Account for possibility of partial token from previous call. */ |
| read_len = 4 - dec->buf_len; |
| |
| /* Detect invalid input. */ |
| for (i = 0; i < read_len; i++) { |
| sval = dec->src[src_off + i]; |
| if (sval == '\0') { |
| /* Incomplete input. */ |
| return -1; |
| } |
| if (sval != '=' && strchr(base64_chars, sval) == NULL) { |
| /* Invalid base64 character. */ |
| return -1; |
| } |
| } |
| |
| if (src_rem < read_len) { |
| /* Input contains a partial token. Stash it for use during the |
| * next call. |
| */ |
| memcpy(&dec->buf[dec->buf_len], &dec->src[src_off], src_rem); |
| dec->buf_len += src_rem; |
| break; |
| } |
| |
| /* Copy full token into buf and decode it. */ |
| memcpy(&dec->buf[dec->buf_len], &dec->src[src_off], read_len); |
| val = token_decode(dec->buf, read_len); |
| if (val == DECODE_ERROR) { |
| return -1; |
| } |
| src_off += read_len; |
| dec->buf_len = 0; |
| |
| marker = (val >> 24) & 0xff; |
| |
| if (dst_off >= dst_len) { |
| break; |
| } |
| dst[dst_off] = (val >> 16) & 0xff; |
| dst_off++; |
| |
| if (marker < 2) { |
| if (dst_off >= dst_len) { |
| break; |
| } |
| dst[dst_off] = (val >> 8) & 0xff; |
| dst_off++; |
| } |
| |
| if (marker < 1) { |
| if (dst_off >= dst_len) { |
| break; |
| } |
| dst[dst_off] = val & 0xff; |
| dst_off++; |
| } |
| } |
| |
| return dst_off; |
| } |