diff options
Diffstat (limited to 'lib/mbedtls-2.27.0/library/base64.c')
| -rw-r--r-- | lib/mbedtls-2.27.0/library/base64.c | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/lib/mbedtls-2.27.0/library/base64.c b/lib/mbedtls-2.27.0/library/base64.c new file mode 100644 index 0000000..1a05226 --- /dev/null +++ b/lib/mbedtls-2.27.0/library/base64.c @@ -0,0 +1,396 @@ +/* + * RFC 1521 base64 encoding/decoding + * + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed 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. + */ + +#include "common.h" + +#if defined(MBEDTLS_BASE64_C) + +#include "mbedtls/base64.h" + +#include <stdint.h> + +#if defined(MBEDTLS_SELF_TEST) +#include <string.h> +#if defined(MBEDTLS_PLATFORM_C) +#include "mbedtls/platform.h" +#else +#include <stdio.h> +#define mbedtls_printf printf +#endif /* MBEDTLS_PLATFORM_C */ +#endif /* MBEDTLS_SELF_TEST */ + +static const unsigned char base64_enc_map[64] = +{ + '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', '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', '0', '1', '2', '3', '4', '5', '6', '7', + '8', '9', '+', '/' +}; + +static const unsigned char base64_dec_map[128] = +{ + 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, + 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, + 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, + 127, 127, 127, 127, 127, 127, 127, 127, 127, 127, + 127, 127, 127, 62, 127, 127, 127, 63, 52, 53, + 54, 55, 56, 57, 58, 59, 60, 61, 127, 127, + 127, 64, 127, 127, 127, 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, 127, 127, 127, 127, 127, 127, 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, 127, 127, 127, 127, 127 +}; + +#define BASE64_SIZE_T_MAX ( (size_t) -1 ) /* SIZE_T_MAX is not standard */ + +/* + * Constant flow conditional assignment to unsigned char + */ +static void mbedtls_base64_cond_assign_uchar( unsigned char * dest, const unsigned char * const src, + unsigned char condition ) +{ + /* MSVC has a warning about unary minus on unsigned integer types, + * but this is well-defined and precisely what we want to do here. */ +#if defined(_MSC_VER) +#pragma warning( push ) +#pragma warning( disable : 4146 ) +#endif + + /* Generate bitmask from condition, mask will either be 0xFF or 0 */ + unsigned char mask = ( condition | -condition ); + mask >>= 7; + mask = -mask; + +#if defined(_MSC_VER) +#pragma warning( pop ) +#endif + + *dest = ( ( *src ) & mask ) | ( ( *dest ) & ~mask ); +} + +/* + * Constant flow conditional assignment to uint_32 + */ +static void mbedtls_base64_cond_assign_uint32( uint32_t * dest, const uint32_t src, + uint32_t condition ) +{ + /* MSVC has a warning about unary minus on unsigned integer types, + * but this is well-defined and precisely what we want to do here. */ +#if defined(_MSC_VER) +#pragma warning( push ) +#pragma warning( disable : 4146 ) +#endif + + /* Generate bitmask from condition, mask will either be 0xFFFFFFFF or 0 */ + uint32_t mask = ( condition | -condition ); + mask >>= 31; + mask = -mask; + +#if defined(_MSC_VER) +#pragma warning( pop ) +#endif + + *dest = ( src & mask ) | ( ( *dest ) & ~mask ); +} + +/* + * Constant flow check for equality + */ +static unsigned char mbedtls_base64_eq( size_t in_a, size_t in_b ) +{ + size_t difference = in_a ^ in_b; + + /* MSVC has a warning about unary minus on unsigned integer types, + * but this is well-defined and precisely what we want to do here. */ +#if defined(_MSC_VER) +#pragma warning( push ) +#pragma warning( disable : 4146 ) +#endif + + difference |= -difference; + +#if defined(_MSC_VER) +#pragma warning( pop ) +#endif + + /* cope with the varying size of size_t per platform */ + difference >>= ( sizeof( difference ) * 8 - 1 ); + + return (unsigned char) ( 1 ^ difference ); +} + +/* + * Constant flow lookup into table. + */ +static unsigned char mbedtls_base64_table_lookup( const unsigned char * const table, + const size_t table_size, const size_t table_index ) +{ + size_t i; + unsigned char result = 0; + + for( i = 0; i < table_size; ++i ) + { + mbedtls_base64_cond_assign_uchar( &result, &table[i], mbedtls_base64_eq( i, table_index ) ); + } + + return result; +} + +/* + * Encode a buffer into base64 format + */ +int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, + const unsigned char *src, size_t slen ) +{ + size_t i, n; + int C1, C2, C3; + unsigned char *p; + + if( slen == 0 ) + { + *olen = 0; + return( 0 ); + } + + n = slen / 3 + ( slen % 3 != 0 ); + + if( n > ( BASE64_SIZE_T_MAX - 1 ) / 4 ) + { + *olen = BASE64_SIZE_T_MAX; + return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL ); + } + + n *= 4; + + if( ( dlen < n + 1 ) || ( NULL == dst ) ) + { + *olen = n + 1; + return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL ); + } + + n = ( slen / 3 ) * 3; + + for( i = 0, p = dst; i < n; i += 3 ) + { + C1 = *src++; + C2 = *src++; + C3 = *src++; + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( C1 >> 2 ) & 0x3F ) ); + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) & 0x3F ) ); + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( ( ( C2 & 15 ) << 2 ) + ( C3 >> 6 ) ) & 0x3F ) ); + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( C3 & 0x3F ) ); + } + + if( i < slen ) + { + C1 = *src++; + C2 = ( ( i + 1 ) < slen ) ? *src++ : 0; + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( C1 >> 2 ) & 0x3F ) ); + + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) & 0x3F ) ); + + if( ( i + 1 ) < slen ) + *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), + ( ( ( C2 & 15 ) << 2 ) & 0x3F ) ); + else *p++ = '='; + + *p++ = '='; + } + + *olen = p - dst; + *p = 0; + + return( 0 ); +} + +/* + * Decode a base64-formatted buffer + */ +int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, + const unsigned char *src, size_t slen ) +{ + size_t i, n; + uint32_t j, x; + unsigned char *p; + unsigned char dec_map_lookup; + + /* First pass: check for validity and get output length */ + for( i = n = j = 0; i < slen; i++ ) + { + /* Skip spaces before checking for EOL */ + x = 0; + while( i < slen && src[i] == ' ' ) + { + ++i; + ++x; + } + + /* Spaces at end of buffer are OK */ + if( i == slen ) + break; + + if( ( slen - i ) >= 2 && + src[i] == '\r' && src[i + 1] == '\n' ) + continue; + + if( src[i] == '\n' ) + continue; + + /* Space inside a line is an error */ + if( x != 0 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + + if( src[i] == '=' && ++j > 2 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + + dec_map_lookup = mbedtls_base64_table_lookup( base64_dec_map, sizeof( base64_dec_map ), src[i] ); + + if( src[i] > 127 || dec_map_lookup == 127 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + + if( dec_map_lookup < 64 && j != 0 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + + n++; + } + + if( n == 0 ) + { + *olen = 0; + return( 0 ); + } + + /* The following expression is to calculate the following formula without + * risk of integer overflow in n: + * n = ( ( n * 6 ) + 7 ) >> 3; + */ + n = ( 6 * ( n >> 3 ) ) + ( ( 6 * ( n & 0x7 ) + 7 ) >> 3 ); + n -= j; + + if( dst == NULL || dlen < n ) + { + *olen = n; + return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL ); + } + + for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ ) + { + if( *src == '\r' || *src == '\n' || *src == ' ' ) + continue; + + dec_map_lookup = mbedtls_base64_table_lookup( base64_dec_map, sizeof( base64_dec_map ), *src ); + + mbedtls_base64_cond_assign_uint32( &j, j - 1, mbedtls_base64_eq( dec_map_lookup, 64 ) ); + x = ( x << 6 ) | ( dec_map_lookup & 0x3F ); + + if( ++n == 4 ) + { + n = 0; + if( j > 0 ) *p++ = (unsigned char)( x >> 16 ); + if( j > 1 ) *p++ = (unsigned char)( x >> 8 ); + if( j > 2 ) *p++ = (unsigned char)( x ); + } + } + + *olen = p - dst; + + return( 0 ); +} + +#if defined(MBEDTLS_SELF_TEST) + +static const unsigned char base64_test_dec[64] = +{ + 0x24, 0x48, 0x6E, 0x56, 0x87, 0x62, 0x5A, 0xBD, + 0xBF, 0x17, 0xD9, 0xA2, 0xC4, 0x17, 0x1A, 0x01, + 0x94, 0xED, 0x8F, 0x1E, 0x11, 0xB3, 0xD7, 0x09, + 0x0C, 0xB6, 0xE9, 0x10, 0x6F, 0x22, 0xEE, 0x13, + 0xCA, 0xB3, 0x07, 0x05, 0x76, 0xC9, 0xFA, 0x31, + 0x6C, 0x08, 0x34, 0xFF, 0x8D, 0xC2, 0x6C, 0x38, + 0x00, 0x43, 0xE9, 0x54, 0x97, 0xAF, 0x50, 0x4B, + 0xD1, 0x41, 0xBA, 0x95, 0x31, 0x5A, 0x0B, 0x97 +}; + +static const unsigned char base64_test_enc[] = + "JEhuVodiWr2/F9mixBcaAZTtjx4Rs9cJDLbpEG8i7hPK" + "swcFdsn6MWwINP+Nwmw4AEPpVJevUEvRQbqVMVoLlw=="; + +/* + * Checkup routine + */ +int mbedtls_base64_self_test( int verbose ) +{ + size_t len; + const unsigned char *src; + unsigned char buffer[128]; + + if( verbose != 0 ) + mbedtls_printf( " Base64 encoding test: " ); + + src = base64_test_dec; + + if( mbedtls_base64_encode( buffer, sizeof( buffer ), &len, src, 64 ) != 0 || + memcmp( base64_test_enc, buffer, 88 ) != 0 ) + { + if( verbose != 0 ) + mbedtls_printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + mbedtls_printf( "passed\n Base64 decoding test: " ); + + src = base64_test_enc; + + if( mbedtls_base64_decode( buffer, sizeof( buffer ), &len, src, 88 ) != 0 || + memcmp( base64_test_dec, buffer, 64 ) != 0 ) + { + if( verbose != 0 ) + mbedtls_printf( "failed\n" ); + + return( 1 ); + } + + if( verbose != 0 ) + mbedtls_printf( "passed\n\n" ); + + return( 0 ); +} + +#endif /* MBEDTLS_SELF_TEST */ + +#endif /* MBEDTLS_BASE64_C */ |