Modified mbed TLS headers for AES functionality only to reduce build size
Dependents: BLE_Gateway_Linker_fix BLE_Gateway
Fork of mbedtls by
Diff: source/memory_buffer_alloc.c
- Revision:
- 1:24750b9ad5ef
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/source/memory_buffer_alloc.c Fri Jan 22 16:44:49 2016 -0600 @@ -0,0 +1,750 @@ +/* + * Buffer-based memory allocator + * + * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved + * 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. + * + * This file is part of mbed TLS (https://tls.mbed.org) + */ + +#if !defined(MBEDTLS_CONFIG_FILE) +#include "mbedtls/config.h" +#else +#include MBEDTLS_CONFIG_FILE +#endif + +#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C) +#include "mbedtls/memory_buffer_alloc.h" + +/* No need for the header guard as MBEDTLS_MEMORY_BUFFER_ALLOC_C + is dependent upon MBEDTLS_PLATFORM_C */ +#include "mbedtls/platform.h" + +#include <string.h> + +#if defined(MBEDTLS_MEMORY_BACKTRACE) +#include <execinfo.h> +#endif + +#if defined(MBEDTLS_THREADING_C) +#include "mbedtls/threading.h" +#endif + +/* Implementation that should never be optimized out by the compiler */ +static void mbedtls_zeroize( void *v, size_t n ) { + volatile unsigned char *p = v; while( n-- ) *p++ = 0; +} + +#define MAGIC1 0xFF00AA55 +#define MAGIC2 0xEE119966 +#define MAX_BT 20 + +typedef struct _memory_header memory_header; +struct _memory_header +{ + size_t magic1; + size_t size; + size_t alloc; + memory_header *prev; + memory_header *next; + memory_header *prev_free; + memory_header *next_free; +#if defined(MBEDTLS_MEMORY_BACKTRACE) + char **trace; + size_t trace_count; +#endif + size_t magic2; +}; + +typedef struct +{ + unsigned char *buf; + size_t len; + memory_header *first; + memory_header *first_free; + int verify; +#if defined(MBEDTLS_MEMORY_DEBUG) + size_t alloc_count; + size_t free_count; + size_t total_used; + size_t maximum_used; + size_t header_count; + size_t maximum_header_count; +#endif +#if defined(MBEDTLS_THREADING_C) + mbedtls_threading_mutex_t mutex; +#endif +} +buffer_alloc_ctx; + +static buffer_alloc_ctx heap; + +#if defined(MBEDTLS_MEMORY_DEBUG) +static void debug_header( memory_header *hdr ) +{ +#if defined(MBEDTLS_MEMORY_BACKTRACE) + size_t i; +#endif + + mbedtls_fprintf( stderr, "HDR: PTR(%10zu), PREV(%10zu), NEXT(%10zu), " + "ALLOC(%zu), SIZE(%10zu)\n", + (size_t) hdr, (size_t) hdr->prev, (size_t) hdr->next, + hdr->alloc, hdr->size ); + mbedtls_fprintf( stderr, " FPREV(%10zu), FNEXT(%10zu)\n", + (size_t) hdr->prev_free, (size_t) hdr->next_free ); + +#if defined(MBEDTLS_MEMORY_BACKTRACE) + mbedtls_fprintf( stderr, "TRACE: \n" ); + for( i = 0; i < hdr->trace_count; i++ ) + mbedtls_fprintf( stderr, "%s\n", hdr->trace[i] ); + mbedtls_fprintf( stderr, "\n" ); +#endif +} + +static void debug_chain() +{ + memory_header *cur = heap.first; + + mbedtls_fprintf( stderr, "\nBlock list\n" ); + while( cur != NULL ) + { + debug_header( cur ); + cur = cur->next; + } + + mbedtls_fprintf( stderr, "Free list\n" ); + cur = heap.first_free; + + while( cur != NULL ) + { + debug_header( cur ); + cur = cur->next_free; + } +} +#endif /* MBEDTLS_MEMORY_DEBUG */ + +static int verify_header( memory_header *hdr ) +{ + if( hdr->magic1 != MAGIC1 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: MAGIC1 mismatch\n" ); +#endif + return( 1 ); + } + + if( hdr->magic2 != MAGIC2 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: MAGIC2 mismatch\n" ); +#endif + return( 1 ); + } + + if( hdr->alloc > 1 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: alloc has illegal value\n" ); +#endif + return( 1 ); + } + + if( hdr->prev != NULL && hdr->prev == hdr->next ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: prev == next\n" ); +#endif + return( 1 ); + } + + if( hdr->prev_free != NULL && hdr->prev_free == hdr->next_free ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: prev_free == next_free\n" ); +#endif + return( 1 ); + } + + return( 0 ); +} + +static int verify_chain() +{ + memory_header *prv = heap.first, *cur = heap.first->next; + + if( verify_header( heap.first ) != 0 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: verification of first header " + "failed\n" ); +#endif + return( 1 ); + } + + if( heap.first->prev != NULL ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: verification failed: " + "first->prev != NULL\n" ); +#endif + return( 1 ); + } + + while( cur != NULL ) + { + if( verify_header( cur ) != 0 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: verification of header " + "failed\n" ); +#endif + return( 1 ); + } + + if( cur->prev != prv ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: verification failed: " + "cur->prev != prv\n" ); +#endif + return( 1 ); + } + + prv = cur; + cur = cur->next; + } + + return( 0 ); +} + +static void *buffer_alloc_calloc( size_t n, size_t size ) +{ + memory_header *new, *cur = heap.first_free; + unsigned char *p; + void *ret; + size_t original_len, len; +#if defined(MBEDTLS_MEMORY_BACKTRACE) + void *trace_buffer[MAX_BT]; + size_t trace_cnt; +#endif + + if( heap.buf == NULL || heap.first == NULL ) + return( NULL ); + + original_len = len = n * size; + + if( n != 0 && len / n != size ) + return( NULL ); + + if( len % MBEDTLS_MEMORY_ALIGN_MULTIPLE ) + { + len -= len % MBEDTLS_MEMORY_ALIGN_MULTIPLE; + len += MBEDTLS_MEMORY_ALIGN_MULTIPLE; + } + + // Find block that fits + // + while( cur != NULL ) + { + if( cur->size >= len ) + break; + + cur = cur->next_free; + } + + if( cur == NULL ) + return( NULL ); + + if( cur->alloc != 0 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: block in free_list but allocated " + "data\n" ); +#endif + mbedtls_exit( 1 ); + } + +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.alloc_count++; +#endif + + // Found location, split block if > memory_header + 4 room left + // + if( cur->size - len < sizeof(memory_header) + + MBEDTLS_MEMORY_ALIGN_MULTIPLE ) + { + cur->alloc = 1; + + // Remove from free_list + // + if( cur->prev_free != NULL ) + cur->prev_free->next_free = cur->next_free; + else + heap.first_free = cur->next_free; + + if( cur->next_free != NULL ) + cur->next_free->prev_free = cur->prev_free; + + cur->prev_free = NULL; + cur->next_free = NULL; + +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.total_used += cur->size; + if( heap.total_used > heap.maximum_used ) + heap.maximum_used = heap.total_used; +#endif +#if defined(MBEDTLS_MEMORY_BACKTRACE) + trace_cnt = backtrace( trace_buffer, MAX_BT ); + cur->trace = backtrace_symbols( trace_buffer, trace_cnt ); + cur->trace_count = trace_cnt; +#endif + + if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 ) + mbedtls_exit( 1 ); + + ret = (unsigned char *) cur + sizeof( memory_header ); + memset( ret, 0, original_len ); + + return( ret ); + } + + p = ( (unsigned char *) cur ) + sizeof(memory_header) + len; + new = (memory_header *) p; + + new->size = cur->size - len - sizeof(memory_header); + new->alloc = 0; + new->prev = cur; + new->next = cur->next; +#if defined(MBEDTLS_MEMORY_BACKTRACE) + new->trace = NULL; + new->trace_count = 0; +#endif + new->magic1 = MAGIC1; + new->magic2 = MAGIC2; + + if( new->next != NULL ) + new->next->prev = new; + + // Replace cur with new in free_list + // + new->prev_free = cur->prev_free; + new->next_free = cur->next_free; + if( new->prev_free != NULL ) + new->prev_free->next_free = new; + else + heap.first_free = new; + + if( new->next_free != NULL ) + new->next_free->prev_free = new; + + cur->alloc = 1; + cur->size = len; + cur->next = new; + cur->prev_free = NULL; + cur->next_free = NULL; + +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.header_count++; + if( heap.header_count > heap.maximum_header_count ) + heap.maximum_header_count = heap.header_count; + heap.total_used += cur->size; + if( heap.total_used > heap.maximum_used ) + heap.maximum_used = heap.total_used; +#endif +#if defined(MBEDTLS_MEMORY_BACKTRACE) + trace_cnt = backtrace( trace_buffer, MAX_BT ); + cur->trace = backtrace_symbols( trace_buffer, trace_cnt ); + cur->trace_count = trace_cnt; +#endif + + if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 ) + mbedtls_exit( 1 ); + + ret = (unsigned char *) cur + sizeof( memory_header ); + memset( ret, 0, original_len ); + + return( ret ); +} + +static void buffer_alloc_free( void *ptr ) +{ + memory_header *hdr, *old = NULL; + unsigned char *p = (unsigned char *) ptr; + + if( ptr == NULL || heap.buf == NULL || heap.first == NULL ) + return; + + if( p < heap.buf || p > heap.buf + heap.len ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: mbedtls_free() outside of managed " + "space\n" ); +#endif + mbedtls_exit( 1 ); + } + + p -= sizeof(memory_header); + hdr = (memory_header *) p; + + if( verify_header( hdr ) != 0 ) + mbedtls_exit( 1 ); + + if( hdr->alloc != 1 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + mbedtls_fprintf( stderr, "FATAL: mbedtls_free() on unallocated " + "data\n" ); +#endif + mbedtls_exit( 1 ); + } + + hdr->alloc = 0; + +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.free_count++; + heap.total_used -= hdr->size; +#endif + + // Regroup with block before + // + if( hdr->prev != NULL && hdr->prev->alloc == 0 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.header_count--; +#endif + hdr->prev->size += sizeof(memory_header) + hdr->size; + hdr->prev->next = hdr->next; + old = hdr; + hdr = hdr->prev; + + if( hdr->next != NULL ) + hdr->next->prev = hdr; + +#if defined(MBEDTLS_MEMORY_BACKTRACE) + free( old->trace ); +#endif + memset( old, 0, sizeof(memory_header) ); + } + + // Regroup with block after + // + if( hdr->next != NULL && hdr->next->alloc == 0 ) + { +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.header_count--; +#endif + hdr->size += sizeof(memory_header) + hdr->next->size; + old = hdr->next; + hdr->next = hdr->next->next; + + if( hdr->prev_free != NULL || hdr->next_free != NULL ) + { + if( hdr->prev_free != NULL ) + hdr->prev_free->next_free = hdr->next_free; + else + heap.first_free = hdr->next_free; + + if( hdr->next_free != NULL ) + hdr->next_free->prev_free = hdr->prev_free; + } + + hdr->prev_free = old->prev_free; + hdr->next_free = old->next_free; + + if( hdr->prev_free != NULL ) + hdr->prev_free->next_free = hdr; + else + heap.first_free = hdr; + + if( hdr->next_free != NULL ) + hdr->next_free->prev_free = hdr; + + if( hdr->next != NULL ) + hdr->next->prev = hdr; + +#if defined(MBEDTLS_MEMORY_BACKTRACE) + free( old->trace ); +#endif + memset( old, 0, sizeof(memory_header) ); + } + + // Prepend to free_list if we have not merged + // (Does not have to stay in same order as prev / next list) + // + if( old == NULL ) + { + hdr->next_free = heap.first_free; + if( heap.first_free != NULL ) + heap.first_free->prev_free = hdr; + heap.first_free = hdr; + } + +#if defined(MBEDTLS_MEMORY_BACKTRACE) + hdr->trace = NULL; + hdr->trace_count = 0; +#endif + + if( ( heap.verify & MBEDTLS_MEMORY_VERIFY_FREE ) && verify_chain() != 0 ) + mbedtls_exit( 1 ); +} + +void mbedtls_memory_buffer_set_verify( int verify ) +{ + heap.verify = verify; +} + +int mbedtls_memory_buffer_alloc_verify() +{ + return verify_chain(); +} + +#if defined(MBEDTLS_MEMORY_DEBUG) +void mbedtls_memory_buffer_alloc_status() +{ + mbedtls_fprintf( stderr, + "Current use: %zu blocks / %zu bytes, max: %zu blocks / " + "%zu bytes (total %zu bytes), alloc / free: %zu / %zu\n", + heap.header_count, heap.total_used, + heap.maximum_header_count, heap.maximum_used, + heap.maximum_header_count * sizeof( memory_header ) + + heap.maximum_used, + heap.alloc_count, heap.free_count ); + + if( heap.first->next == NULL ) + mbedtls_fprintf( stderr, "All memory de-allocated in stack buffer\n" ); + else + { + mbedtls_fprintf( stderr, "Memory currently allocated:\n" ); + debug_chain(); + } +} + +void mbedtls_memory_buffer_alloc_max_get( size_t *max_used, size_t *max_blocks ) +{ + *max_used = heap.maximum_used; + *max_blocks = heap.maximum_header_count; +} + +void mbedtls_memory_buffer_alloc_max_reset( void ) +{ + heap.maximum_used = 0; + heap.maximum_header_count = 0; +} + +void mbedtls_memory_buffer_alloc_cur_get( size_t *cur_used, size_t *cur_blocks ) +{ + *cur_used = heap.total_used; + *cur_blocks = heap.header_count; +} +#endif /* MBEDTLS_MEMORY_DEBUG */ + +#if defined(MBEDTLS_THREADING_C) +static void *buffer_alloc_calloc_mutexed( size_t n, size_t size ) +{ + void *buf; + if( mbedtls_mutex_lock( &heap.mutex ) != 0 ) + return( NULL ); + buf = buffer_alloc_calloc( n, size ); + if( mbedtls_mutex_unlock( &heap.mutex ) ) + return( NULL ); + return( buf ); +} + +static void buffer_alloc_free_mutexed( void *ptr ) +{ + /* We have to good option here, but corrupting the heap seems + * worse than loosing memory. */ + if( mbedtls_mutex_lock( &heap.mutex ) ) + return; + buffer_alloc_free( ptr ); + (void) mbedtls_mutex_unlock( &heap.mutex ); +} +#endif /* MBEDTLS_THREADING_C */ + +void mbedtls_memory_buffer_alloc_init( unsigned char *buf, size_t len ) +{ + memset( &heap, 0, sizeof(buffer_alloc_ctx) ); + memset( buf, 0, len ); + +#if defined(MBEDTLS_THREADING_C) + mbedtls_mutex_init( &heap.mutex ); + mbedtls_platform_set_calloc_free( buffer_alloc_calloc_mutexed, + buffer_alloc_free_mutexed ); +#else + mbedtls_platform_set_calloc_free( buffer_alloc_calloc, buffer_alloc_free ); +#endif + + if( (size_t) buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE ) + { + /* Adjust len first since buf is used in the computation */ + len -= MBEDTLS_MEMORY_ALIGN_MULTIPLE + - (size_t) buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE; + buf += MBEDTLS_MEMORY_ALIGN_MULTIPLE + - (size_t) buf % MBEDTLS_MEMORY_ALIGN_MULTIPLE; + } + + heap.buf = buf; + heap.len = len; + + heap.first = (memory_header *) buf; + heap.first->size = len - sizeof(memory_header); + heap.first->magic1 = MAGIC1; + heap.first->magic2 = MAGIC2; + heap.first_free = heap.first; +} + +void mbedtls_memory_buffer_alloc_free() +{ +#if defined(MBEDTLS_THREADING_C) + mbedtls_mutex_free( &heap.mutex ); +#endif + mbedtls_zeroize( &heap, sizeof(buffer_alloc_ctx) ); +} + +#if defined(MBEDTLS_SELF_TEST) +static int check_pointer( void *p ) +{ + if( p == NULL ) + return( -1 ); + + if( (size_t) p % MBEDTLS_MEMORY_ALIGN_MULTIPLE != 0 ) + return( -1 ); + + return( 0 ); +} + +static int check_all_free( ) +{ + if( +#if defined(MBEDTLS_MEMORY_DEBUG) + heap.total_used != 0 || +#endif + heap.first != heap.first_free || + (void *) heap.first != (void *) heap.buf ) + { + return( -1 ); + } + + return( 0 ); +} + +#define TEST_ASSERT( condition ) \ + if( ! (condition) ) \ + { \ + if( verbose != 0 ) \ + mbedtls_printf( "failed\n" ); \ + \ + ret = 1; \ + goto cleanup; \ + } + +int mbedtls_memory_buffer_alloc_self_test( int verbose ) +{ + unsigned char buf[1024]; + unsigned char *p, *q, *r, *end; + int ret = 0; + + if( verbose != 0 ) + mbedtls_printf( " MBA test #1 (basic alloc-free cycle): " ); + + mbedtls_memory_buffer_alloc_init( buf, sizeof( buf ) ); + + p = mbedtls_calloc( 1, 1 ); + q = mbedtls_calloc( 1, 128 ); + r = mbedtls_calloc( 1, 16 ); + + TEST_ASSERT( check_pointer( p ) == 0 && + check_pointer( q ) == 0 && + check_pointer( r ) == 0 ); + + mbedtls_free( r ); + mbedtls_free( q ); + mbedtls_free( p ); + + TEST_ASSERT( check_all_free( ) == 0 ); + + /* Memorize end to compare with the next test */ + end = heap.buf + heap.len; + + mbedtls_memory_buffer_alloc_free( ); + + if( verbose != 0 ) + mbedtls_printf( "passed\n" ); + + if( verbose != 0 ) + mbedtls_printf( " MBA test #2 (buf not aligned): " ); + + mbedtls_memory_buffer_alloc_init( buf + 1, sizeof( buf ) - 1 ); + + TEST_ASSERT( heap.buf + heap.len == end ); + + p = mbedtls_calloc( 1, 1 ); + q = mbedtls_calloc( 1, 128 ); + r = mbedtls_calloc( 1, 16 ); + + TEST_ASSERT( check_pointer( p ) == 0 && + check_pointer( q ) == 0 && + check_pointer( r ) == 0 ); + + mbedtls_free( r ); + mbedtls_free( q ); + mbedtls_free( p ); + + TEST_ASSERT( check_all_free( ) == 0 ); + + mbedtls_memory_buffer_alloc_free( ); + + if( verbose != 0 ) + mbedtls_printf( "passed\n" ); + + if( verbose != 0 ) + mbedtls_printf( " MBA test #3 (full): " ); + + mbedtls_memory_buffer_alloc_init( buf, sizeof( buf ) ); + + p = mbedtls_calloc( 1, sizeof( buf ) - sizeof( memory_header ) ); + + TEST_ASSERT( check_pointer( p ) == 0 ); + TEST_ASSERT( mbedtls_calloc( 1, 1 ) == NULL ); + + mbedtls_free( p ); + + p = mbedtls_calloc( 1, sizeof( buf ) - 2 * sizeof( memory_header ) - 16 ); + q = mbedtls_calloc( 1, 16 ); + + TEST_ASSERT( check_pointer( p ) == 0 && check_pointer( q ) == 0 ); + TEST_ASSERT( mbedtls_calloc( 1, 1 ) == NULL ); + + mbedtls_free( q ); + + TEST_ASSERT( mbedtls_calloc( 1, 17 ) == NULL ); + + mbedtls_free( p ); + + TEST_ASSERT( check_all_free( ) == 0 ); + + mbedtls_memory_buffer_alloc_free( ); + + if( verbose != 0 ) + mbedtls_printf( "passed\n" ); + +cleanup: + mbedtls_memory_buffer_alloc_free( ); + + return( ret ); +} +#endif /* MBEDTLS_SELF_TEST */ + +#endif /* MBEDTLS_MEMORY_BUFFER_ALLOC_C */