| /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| * All rights reserved. |
| * |
| * This package is an SSL implementation written |
| * by Eric Young (eay@cryptsoft.com). |
| * The implementation was written so as to conform with Netscapes SSL. |
| * |
| * This library is free for commercial and non-commercial use as long as |
| * the following conditions are aheared to. The following conditions |
| * apply to all code found in this distribution, be it the RC4, RSA, |
| * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
| * included with this distribution is covered by the same copyright terms |
| * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
| * |
| * Copyright remains Eric Young's, and as such any Copyright notices in |
| * the code are not to be removed. |
| * If this package is used in a product, Eric Young should be given attribution |
| * as the author of the parts of the library used. |
| * This can be in the form of a textual message at program startup or |
| * in documentation (online or textual) provided with the package. |
| * |
| * 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 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. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * "This product includes cryptographic software written by |
| * Eric Young (eay@cryptsoft.com)" |
| * The word 'cryptographic' can be left out if the rouines from the library |
| * being used are not cryptographic related :-). |
| * 4. If you include any Windows specific code (or a derivative thereof) from |
| * the apps directory (application code) you must include an acknowledgement: |
| * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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. |
| * |
| * The licence and distribution terms for any publically available version or |
| * derivative of this code cannot be changed. i.e. this code cannot simply be |
| * copied and put under another distribution licence |
| * [including the GNU Public Licence.] */ |
| |
| #include <openssl/base64.h> |
| |
| #include <assert.h> |
| #include <limits.h> |
| #include <string.h> |
| |
| #include <openssl/type_check.h> |
| |
| |
| /* Encoding. */ |
| |
| static const unsigned char data_bin2ascii[65] = |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
| |
| #define conv_bin2ascii(a) (data_bin2ascii[(a) & 0x3f]) |
| |
| OPENSSL_COMPILE_ASSERT(sizeof(((EVP_ENCODE_CTX *)(NULL))->data) % 3 == 0, |
| data_length_must_be_multiple_of_base64_chunk_size); |
| |
| int EVP_EncodedLength(size_t *out_len, size_t len) { |
| if (len + 2 < len) { |
| return 0; |
| } |
| len += 2; |
| len /= 3; |
| |
| if (((len << 2) >> 2) != len) { |
| return 0; |
| } |
| len <<= 2; |
| |
| if (len + 1 < len) { |
| return 0; |
| } |
| len++; |
| |
| *out_len = len; |
| return 1; |
| } |
| |
| void EVP_EncodeInit(EVP_ENCODE_CTX *ctx) { |
| memset(ctx, 0, sizeof(EVP_ENCODE_CTX)); |
| } |
| |
| void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out, int *out_len, |
| const uint8_t *in, size_t in_len) { |
| size_t total = 0; |
| |
| *out_len = 0; |
| if (in_len == 0) { |
| return; |
| } |
| |
| assert(ctx->data_used < sizeof(ctx->data)); |
| |
| if (sizeof(ctx->data) - ctx->data_used > in_len) { |
| memcpy(&ctx->data[ctx->data_used], in, in_len); |
| ctx->data_used += (unsigned)in_len; |
| return; |
| } |
| |
| if (ctx->data_used != 0) { |
| const size_t todo = sizeof(ctx->data) - ctx->data_used; |
| memcpy(&ctx->data[ctx->data_used], in, todo); |
| in += todo; |
| in_len -= todo; |
| |
| size_t encoded = EVP_EncodeBlock(out, ctx->data, sizeof(ctx->data)); |
| ctx->data_used = 0; |
| |
| out += encoded; |
| *(out++) = '\n'; |
| *out = '\0'; |
| |
| total = encoded + 1; |
| } |
| |
| while (in_len >= sizeof(ctx->data)) { |
| size_t encoded = EVP_EncodeBlock(out, in, sizeof(ctx->data)); |
| in += sizeof(ctx->data); |
| in_len -= sizeof(ctx->data); |
| |
| out += encoded; |
| *(out++) = '\n'; |
| *out = '\0'; |
| |
| if (total + encoded + 1 < total) { |
| *out_len = 0; |
| return; |
| } |
| |
| total += encoded + 1; |
| } |
| |
| if (in_len != 0) { |
| memcpy(ctx->data, in, in_len); |
| } |
| |
| ctx->data_used = (unsigned)in_len; |
| |
| if (total > INT_MAX) { |
| /* We cannot signal an error, but we can at least avoid making *out_len |
| * negative. */ |
| total = 0; |
| } |
| *out_len = (int)total; |
| } |
| |
| void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out, int *out_len) { |
| if (ctx->data_used == 0) { |
| *out_len = 0; |
| return; |
| } |
| |
| size_t encoded = EVP_EncodeBlock(out, ctx->data, ctx->data_used); |
| out[encoded++] = '\n'; |
| out[encoded] = '\0'; |
| ctx->data_used = 0; |
| |
| /* ctx->data_used is bounded by sizeof(ctx->data), so this does not |
| * overflow. */ |
| assert(encoded <= INT_MAX); |
| *out_len = (int)encoded; |
| } |
| |
| size_t EVP_EncodeBlock(uint8_t *dst, const uint8_t *src, size_t src_len) { |
| uint32_t l; |
| size_t remaining = src_len, ret = 0; |
| |
| while (remaining) { |
| if (remaining >= 3) { |
| l = (((uint32_t)src[0]) << 16L) | (((uint32_t)src[1]) << 8L) | src[2]; |
| *(dst++) = conv_bin2ascii(l >> 18L); |
| *(dst++) = conv_bin2ascii(l >> 12L); |
| *(dst++) = conv_bin2ascii(l >> 6L); |
| *(dst++) = conv_bin2ascii(l); |
| remaining -= 3; |
| } else { |
| l = ((uint32_t)src[0]) << 16L; |
| if (remaining == 2) { |
| l |= ((uint32_t)src[1] << 8L); |
| } |
| |
| *(dst++) = conv_bin2ascii(l >> 18L); |
| *(dst++) = conv_bin2ascii(l >> 12L); |
| *(dst++) = (remaining == 1) ? '=' : conv_bin2ascii(l >> 6L); |
| *(dst++) = '='; |
| remaining = 0; |
| } |
| ret += 4; |
| src += 3; |
| } |
| |
| *dst = '\0'; |
| return ret; |
| } |
| |
| |
| /* Decoding. */ |
| |
| int EVP_DecodedLength(size_t *out_len, size_t len) { |
| if (len % 4 != 0) { |
| return 0; |
| } |
| |
| *out_len = (len / 4) * 3; |
| return 1; |
| } |
| |
| void EVP_DecodeInit(EVP_ENCODE_CTX *ctx) { |
| memset(ctx, 0, sizeof(EVP_ENCODE_CTX)); |
| } |
| |
| /* kBase64ASCIIToBinData maps characters (c < 128) to their base64 value, or |
| * else 0xff if they are invalid. As a special case, the padding character |
| * ('=') is mapped to zero. */ |
| static const uint8_t kBase64ASCIIToBinData[128] = { |
| 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe0, 0xff, 0xff, |
| 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, |
| 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe0, 0xff, 0xff, 0xff, |
| 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, |
| 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff, 0xff, |
| 0xff, 0x00, 0xff, 0xff, 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, |
| 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, |
| 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, |
| 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, |
| 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, |
| 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, |
| }; |
| |
| static uint8_t base64_ascii_to_bin(uint8_t a) { |
| if (a >= 128) { |
| return 0xFF; |
| } |
| |
| return kBase64ASCIIToBinData[a]; |
| } |
| |
| /* base64_decode_quad decodes a single “quad” (i.e. four characters) of base64 |
| * data and writes up to three bytes to |out|. It sets |*out_num_bytes| to the |
| * number of bytes written, which will be less than three if the quad ended |
| * with padding. It returns one on success or zero on error. */ |
| static int base64_decode_quad(uint8_t *out, size_t *out_num_bytes, |
| const uint8_t *in) { |
| const uint8_t a = base64_ascii_to_bin(in[0]); |
| const uint8_t b = base64_ascii_to_bin(in[1]); |
| const uint8_t c = base64_ascii_to_bin(in[2]); |
| const uint8_t d = base64_ascii_to_bin(in[3]); |
| if (a == 0xff || b == 0xff || c == 0xff || d == 0xff) { |
| return 0; |
| } |
| |
| const uint32_t v = ((uint32_t)a) << 18 | ((uint32_t)b) << 12 | |
| ((uint32_t)c) << 6 | (uint32_t)d; |
| |
| const unsigned padding_pattern = (in[0] == '=') << 3 | |
| (in[1] == '=') << 2 | |
| (in[2] == '=') << 1 | |
| (in[3] == '='); |
| |
| switch (padding_pattern) { |
| case 0: |
| /* The common case of no padding. */ |
| *out_num_bytes = 3; |
| out[0] = v >> 16; |
| out[1] = v >> 8; |
| out[2] = v; |
| break; |
| |
| case 1: /* xxx= */ |
| *out_num_bytes = 2; |
| out[0] = v >> 16; |
| out[1] = v >> 8; |
| break; |
| |
| case 3: /* xx== */ |
| *out_num_bytes = 1; |
| out[0] = v >> 16; |
| break; |
| |
| default: |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, uint8_t *out, int *out_len, |
| const uint8_t *in, size_t in_len) { |
| *out_len = 0; |
| |
| if (ctx->error_encountered) { |
| return -1; |
| } |
| |
| size_t bytes_out = 0, i; |
| for (i = 0; i < in_len; i++) { |
| const char c = in[i]; |
| switch (c) { |
| case ' ': |
| case '\t': |
| case '\r': |
| case '\n': |
| continue; |
| } |
| |
| if (base64_ascii_to_bin(c) == 0xff || ctx->eof_seen) { |
| ctx->error_encountered = 1; |
| return -1; |
| } |
| |
| ctx->data[ctx->data_used++] = c; |
| if (ctx->data_used == 4) { |
| size_t num_bytes_resulting; |
| if (!base64_decode_quad(out, &num_bytes_resulting, ctx->data)) { |
| ctx->error_encountered = 1; |
| return -1; |
| } |
| |
| ctx->data_used = 0; |
| bytes_out += num_bytes_resulting; |
| out += num_bytes_resulting; |
| |
| if (num_bytes_resulting < 3) { |
| ctx->eof_seen = 1; |
| } |
| } |
| } |
| |
| if (bytes_out > INT_MAX) { |
| ctx->error_encountered = 1; |
| *out_len = 0; |
| return -1; |
| } |
| *out_len = (int)bytes_out; |
| |
| if (ctx->eof_seen) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, uint8_t *out, int *out_len) { |
| *out_len = 0; |
| if (ctx->error_encountered || ctx->data_used != 0) { |
| return -1; |
| } |
| |
| return 1; |
| } |
| |
| int EVP_DecodeBase64(uint8_t *out, size_t *out_len, size_t max_out, |
| const uint8_t *in, size_t in_len) { |
| *out_len = 0; |
| |
| if (in_len % 4 != 0) { |
| return 0; |
| } |
| |
| size_t max_len; |
| if (!EVP_DecodedLength(&max_len, in_len) || |
| max_out < max_len) { |
| return 0; |
| } |
| |
| size_t i, bytes_out = 0; |
| for (i = 0; i < in_len; i += 4) { |
| size_t num_bytes_resulting; |
| |
| if (!base64_decode_quad(out, &num_bytes_resulting, &in[i])) { |
| return 0; |
| } |
| |
| bytes_out += num_bytes_resulting; |
| out += num_bytes_resulting; |
| if (num_bytes_resulting != 3 && i != in_len - 4) { |
| return 0; |
| } |
| } |
| |
| *out_len = bytes_out; |
| return 1; |
| } |
| |
| int EVP_DecodeBlock(uint8_t *dst, const uint8_t *src, size_t src_len) { |
| /* Trim spaces and tabs from the beginning of the input. */ |
| while (src_len > 0) { |
| if (src[0] != ' ' && src[0] != '\t') { |
| break; |
| } |
| |
| src++; |
| src_len--; |
| } |
| |
| /* Trim newlines, spaces and tabs from the end of the line. */ |
| while (src_len > 0) { |
| switch (src[src_len-1]) { |
| case ' ': |
| case '\t': |
| case '\r': |
| case '\n': |
| src_len--; |
| continue; |
| } |
| |
| break; |
| } |
| |
| size_t dst_len; |
| if (!EVP_DecodedLength(&dst_len, src_len) || |
| dst_len > INT_MAX || |
| !EVP_DecodeBase64(dst, &dst_len, dst_len, src, src_len)) { |
| return -1; |
| } |
| |
| /* EVP_DecodeBlock does not take padding into account, so put the |
| * NULs back in... so the caller can strip them back out. */ |
| while (dst_len % 3 != 0) { |
| dst[dst_len++] = '\0'; |
| } |
| assert(dst_len <= INT_MAX); |
| |
| return (int)dst_len; |
| } |