base64: fork mbedtls 2.25.0 base64 utility to avoid 2.26.0+ performan…

…ce hit

Signed-off-by: Matthew Fala <[email protected]>

include/fluent-bit/flb_base64.h

@@ -0,0 +1,106 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+
+/*  Fluent Bit
+ *  ==========
+ *  Copyright (C) 2019-2021 The Fluent Bit Authors
+ *  Copyright (C) 2015-2018 Treasure Data Inc.
+ *
+ *  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.
+ */
+
+/**
+ * \file base64.h
+ *
+ * \brief RFC 1521 base64 encoding/decoding
+ */
+
+/* This code is based on base64.h from the mbedtls-2.25.0 Library distribution,
+ * as originally written by Paul Bakker, et al., and forked by the Fluent Bit
+ * project to provide performant base64 encoding and decoding routines.
+ * The 2.25.0 implementation is included rather than 2.26.0+ implementation due
+ * to performance degradation introduced in 2.26.0.
+ *
+ * Method and variable names are changed by the Fluent Bit authors to maintain
+ * consistency with the Fluent Bit project.
+ * The self test section of the code was removed by the Fluent Bit authors.
+ * Other minor changes are made by the Fluent Bit authors.
+ *
+ * The original source file base64.h is copyright and licensed as follows;
+ *
+ *  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.
+ */
+
+#ifndef FLB_BASE64_H
+#define FLB_BASE64_H
+
+#include <stddef.h>
+
+#define FLB_BASE64_ERR_BUFFER_TOO_SMALL               -0x002A  /**< Output buffer too small. */
+#define FLB_BASE64_ERR_INVALID_CHARACTER              -0x002C  /**< Invalid character in input. */
+
+/**
+ * \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 FLB_BASE64_ERR_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 flb_base64_encode( unsigned char *dst, size_t dlen, size_t *olen,
+                   const unsigned char *src, size_t slen );
+
+/**
+ * \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, FLB_BASE64_ERR_BUFFER_TOO_SMALL, or
+ *                 FLB_BASE64_ERR_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 flb_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
+                   const unsigned char *src, size_t slen );
+
+#endif /* base64.h */

src/CMakeLists.txt

@@ -59,6 +59,7 @@ set(src
   flb_routes_mask.c
   flb_typecast.c
   flb_event.c
+  flb_base64.c
   )
 
 # Multiline subsystem

src/flb_base64.c

@@ -0,0 +1,239 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+
+/*  Fluent Bit
+ *  ==========
+ *  Copyright (C) 2019-2021 The Fluent Bit Authors
+ *
+ *  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.
+ */
+
+/* This code is based on base64.c from the mbedtls-2.25.0 Library distribution,
+ * as originally written by Paul Bakker, et al., and forked by the Fluent Bit
+ * project to provide performant base64 encoding and decoding routines.
+ * The 2.25.0 implementation is included rather than 2.26.0+ implementation due
+ * to performance degradation introduced in 2.26.0.
+ *
+ * Method and variable names are changed by the Fluent Bit authors to maintain
+ * consistency with the Fluent Bit project.
+ * The self test section of the code was removed by the Fluent Bit authors.
+ * Other minor changes are made by the Fluent Bit authors.
+ *
+ * The original source file base64.c is copyright and licensed as follows;
+ *
+ *  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 <fluent-bit/flb_base64.h>
+
+#include <stdint.h>
+
+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 */
+
+/*
+ * Encode a buffer into base64 format
+ */
+int flb_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( FLB_BASE64_ERR_BUFFER_TOO_SMALL );
+    }
+
+    n *= 4;
+
+    if( ( dlen < n + 1 ) || ( NULL == dst ) )
+    {
+        *olen = n + 1;
+        return( FLB_BASE64_ERR_BUFFER_TOO_SMALL );
+    }
+
+    n = ( slen / 3 ) * 3;
+
+    for( i = 0, p = dst; i < n; i += 3 )
+    {
+        C1 = *src++;
+        C2 = *src++;
+        C3 = *src++;
+
+        *p++ = base64_enc_map[(C1 >> 2) & 0x3F];
+        *p++ = base64_enc_map[(((C1 &  3) << 4) + (C2 >> 4)) & 0x3F];
+        *p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F];
+        *p++ = base64_enc_map[C3 & 0x3F];
+    }
+
+    if( i < slen )
+    {
+        C1 = *src++;
+        C2 = ( ( i + 1 ) < slen ) ? *src++ : 0;
+
+        *p++ = base64_enc_map[(C1 >> 2) & 0x3F];
+        *p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];
+
+        if( ( i + 1 ) < slen )
+             *p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F];
+        else *p++ = '=';
+
+        *p++ = '=';
+    }
+
+    *olen = p - dst;
+    *p = 0;
+
+    return( 0 );
+}
+
+/*
+ * Decode a base64-formatted buffer
+ */
+int flb_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;
+
+    /* 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( FLB_BASE64_ERR_INVALID_CHARACTER );
+
+        if( src[i] == '=' && ++j > 2 )
+            return( FLB_BASE64_ERR_INVALID_CHARACTER );
+
+        if( src[i] > 127 || base64_dec_map[src[i]] == 127 )
+            return( FLB_BASE64_ERR_INVALID_CHARACTER );
+
+        if( base64_dec_map[src[i]] < 64 && j != 0 )
+            return( FLB_BASE64_ERR_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( FLB_BASE64_ERR_BUFFER_TOO_SMALL );
+    }
+
+   for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ )
+   {
+        if( *src == '\r' || *src == '\n' || *src == ' ' )
+            continue;
+
+        j -= ( base64_dec_map[*src] == 64 );
+        x  = ( x << 6 ) | ( base64_dec_map[*src] & 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 );
+}