cosmopolitan/third_party/mbedtls/base64.c
Justine Tunney ae5d06dc53 Unbloat build config
- 10.5% reduction of o//depend dependency graph
- 8.8% reduction in latency of make command
- Fix issue with temporary file cleanup

There's a new -w option in compile.com that turns off the recent
Landlock output path workaround for "good commands" which do not
unlink() the output file like GNU tooling does.

Our new GNU Make unveil sandboxing appears to have zero overhead
in the grand scheme of things. Full builds are pretty fast since
the only thing that's actually slowed us down is probably libcxx

    make -j16 MODE=rel
    RL: took 85,732,063µs wall time
    RL: ballooned to 323,612kb in size
    RL: needed 828,560,521µs cpu (11% kernel)
    RL: caused 39,080,670 page faults (99% memcpy)
    RL: 350,073 context switches (72% consensual)
    RL: performed 0 reads and 11,494,960 write i/o operations

pledge() and unveil() no longer consider ENOSYS to be an error.
These functions have also been added to Python's cosmo module.

This change also removes some WIN32 APIs and System Five magnums
which we're not using and it's doubtful anyone else would be too
2022-08-10 04:43:09 -07:00

305 lines
11 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:4;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright The Mbed TLS Contributors │
│ │
│ 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 "libc/str/str.h"
#include "third_party/mbedtls/base64.h"
#include "third_party/mbedtls/common.h"
#include "third_party/mbedtls/platform.h"
asm(".ident\t\"\\n\\n\
Mbed TLS (Apache 2.0)\\n\
Copyright ARM Limited\\n\
Copyright Mbed TLS Contributors\"");
asm(".include \"libc/disclaimer.inc\"");
/* clang-format off */
#define ENC "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
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
*/
forceinline void mbedtls_base64_cond_assign_uchar( unsigned char * dest,
const unsigned char * const src,
unsigned char condition )
{
/* Generate bitmask from condition, mask will either be 0xFF or 0 */
unsigned char mask = ( condition | -condition );
mask >>= 7;
mask = -mask;
*dest = ( ( *src ) & mask ) | ( ( *dest ) & ~mask );
}
/*
* Constant flow conditional assignment to uint_32
*/
forceinline void mbedtls_base64_cond_assign_uint32( uint32_t * dest, const uint32_t src,
uint32_t condition )
{
/* Generate bitmask from condition, mask will either be 0xFFFFFFFF or 0 */
uint32_t mask = ( condition | -condition );
mask >>= 31;
mask = -mask;
*dest = ( src & mask ) | ( ( *dest ) & ~mask );
}
/*
* Constant flow check for equality
*/
forceinline unsigned char mbedtls_base64_eq( size_t in_a, size_t in_b )
{
size_t difference = in_a ^ in_b;
difference |= -difference;
/* 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 inline unsigned char mbedtls_base64_table_lookup( const unsigned char * const table,
const size_t table_size,
const size_t table_index )
{
return 0 <= table_index && table_index < table_size ? table[table_index] : 127;
/* come on really? */
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;
}
/**
* \brief Encode a buffer into base64 format
*
* \param dst destination buffer
* \param dlen size of the destination buffer
* \param olen number of bytes written
* \param src source buffer
* \param slen amount of data to be encoded
*
* \return 0 if successful, or MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL.
* *olen is always updated to reflect the amount
* of data that has (or would have) been written.
* If that length cannot be represented, then no data is
* written to the buffer and *olen is set to the maximum
* length representable as a size_t.
*
* \note Call this function with dlen = 0 to obtain the
* required buffer size in *olen
*/
int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen,
const unsigned char *src, size_t slen )
{
unsigned w;
size_t i, n;
unsigned char *q;
const unsigned char *p, *pe;
if( !slen ) {
if (dlen) *dst = 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 ) || !dst ) {
*olen = n + 1;
return MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL;
}
for (q = dst, p = src, pe = p + slen; p < pe; p += 3) {
w = p[0] << 020;
if (p + 1 < pe) w |= p[1] << 010;
if (p + 2 < pe) w |= p[2] << 000;
*q++ = ENC[(w >> 18) & 077];
*q++ = ENC[(w >> 12) & 077];
*q++ = p + 1 < pe ? ENC[(w >> 6) & 077] : '=';
*q++ = p + 2 < pe ? ENC[w & 077] : '=';
}
*olen = n;
*q = 0;
return 0;
}
/**
* \brief Decode a base64-formatted buffer
*
* \param dst destination buffer (can be NULL for checking size)
* \param dlen size of the destination buffer
* \param olen number of bytes written
* \param src source buffer
* \param slen amount of data to be decoded
*
* \return 0 if successful, MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL, or
* MBEDTLS_ERR_BASE64_INVALID_CHARACTER if the input data is
* not correct. *olen is always updated to reflect the amount
* of data that has (or would have) been written.
*
* \note Call this function with *dst = NULL or dlen = 0 to obtain
* the required buffer size in *olen
*/
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==";
/**
* \brief Checkup routine
*
* \return 0 if successful, or 1 if the test failed
*/
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 ||
timingsafe_bcmp( 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 ||
timingsafe_bcmp( 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 */