Diff: SSL/library/memory_buffer_alloc.c

Revision:

0:796d0f61a05b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SSL/library/memory_buffer_alloc.c	Thu Sep 27 06:34:22 2018 +0000
@@ -0,0 +1,579 @@
+/*
+ *  Buffer-based memory allocator
+ *
+ *  Copyright (C) 2006-2014, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
+ *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
+ *  All rights reserved.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#if !defined(POLARSSL_CONFIG_FILE)
+#include "polarssl/config.h"
+#else
+#include POLARSSL_CONFIG_FILE
+#endif
+
+#if defined(POLARSSL_MEMORY_BUFFER_ALLOC_C)
+
+#include "polarssl/memory_buffer_alloc.h"
+
+#include <string.h>
+
+#if defined(POLARSSL_MEMORY_DEBUG)
+#include <stdio.h>
+#if defined(POLARSSL_MEMORY_BACKTRACE)
+#include <execinfo.h>
+#endif
+#endif
+
+#if defined(POLARSSL_THREADING_C)
+#include "polarssl/threading.h"
+#endif
+
+#if defined(POLARSSL_PLATFORM_C)
+#include "polarssl/platform.h"
+#else
+#define polarssl_fprintf fprintf
+#endif
+
+#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(POLARSSL_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;
+    size_t          current_alloc_size;
+    int             verify;
+#if defined(POLARSSL_MEMORY_DEBUG)
+    size_t          malloc_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(POLARSSL_THREADING_C)
+    threading_mutex_t   mutex;
+#endif
+}
+buffer_alloc_ctx;
+
+static buffer_alloc_ctx heap;
+
+#if defined(POLARSSL_MEMORY_DEBUG)
+static void debug_header( memory_header *hdr )
+{
+#if defined(POLARSSL_MEMORY_BACKTRACE)
+    size_t i;
+#endif
+
+    polarssl_fprintf( stderr, "HDR:  PTR(%10u), PREV(%10u), NEXT(%10u), "
+                              "ALLOC(%u), SIZE(%10u)\n",
+                      (size_t) hdr, (size_t) hdr->prev, (size_t) hdr->next,
+                      hdr->alloc, hdr->size );
+    polarssl_fprintf( stderr, "      FPREV(%10u), FNEXT(%10u)\n",
+                      (size_t) hdr->prev_free, (size_t) hdr->next_free );
+
+#if defined(POLARSSL_MEMORY_BACKTRACE)
+    polarssl_fprintf( stderr, "TRACE: \n" );
+    for( i = 0; i < hdr->trace_count; i++ )
+        polarssl_fprintf( stderr, "%s\n", hdr->trace[i] );
+    polarssl_fprintf( stderr, "\n" );
+#endif
+}
+
+static void debug_chain()
+{
+    memory_header *cur = heap.first;
+
+    polarssl_fprintf( stderr, "\nBlock list\n" );
+    while( cur != NULL )
+    {
+        debug_header( cur );
+        cur = cur->next;
+    }
+
+    polarssl_fprintf( stderr, "Free list\n" );
+    cur = heap.first_free;
+
+    while( cur != NULL )
+    {
+        debug_header( cur );
+        cur = cur->next_free;
+    }
+}
+#endif /* POLARSSL_MEMORY_DEBUG */
+
+static int verify_header( memory_header *hdr )
+{
+    if( hdr->magic1 != MAGIC1 )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: MAGIC1 mismatch\n" );
+#endif
+        return( 1 );
+    }
+
+    if( hdr->magic2 != MAGIC2 )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: MAGIC2 mismatch\n" );
+#endif
+        return( 1 );
+    }
+
+    if( hdr->alloc > 1 )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: alloc has illegal value\n" );
+#endif
+        return( 1 );
+    }
+
+    if( hdr->prev != NULL && hdr->prev == hdr->next )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: prev == next\n" );
+#endif
+        return( 1 );
+    }
+
+    if( hdr->prev_free != NULL && hdr->prev_free == hdr->next_free )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_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(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: verification of first header "
+                                  "failed\n" );
+#endif
+        return( 1 );
+    }
+
+    if( heap.first->prev != NULL )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: verification failed: "
+                                  "first->prev != NULL\n" );
+#endif
+        return( 1 );
+    }
+
+    while( cur != NULL )
+    {
+        if( verify_header( cur ) != 0 )
+        {
+#if defined(POLARSSL_MEMORY_DEBUG)
+            polarssl_fprintf( stderr, "FATAL: verification of header "
+                                      "failed\n" );
+#endif
+            return( 1 );
+        }
+
+        if( cur->prev != prv )
+        {
+#if defined(POLARSSL_MEMORY_DEBUG)
+            polarssl_fprintf( stderr, "FATAL: verification failed: "
+                                      "cur->prev != prv\n" );
+#endif
+            return( 1 );
+        }
+
+        prv = cur;
+        cur = cur->next;
+    }
+
+    return( 0 );
+}
+
+static void *buffer_alloc_malloc( size_t len )
+{
+    memory_header *new, *cur = heap.first_free;
+    unsigned char *p;
+#if defined(POLARSSL_MEMORY_BACKTRACE)
+    void *trace_buffer[MAX_BT];
+    size_t trace_cnt;
+#endif
+
+    if( heap.buf == NULL || heap.first == NULL )
+        return( NULL );
+
+    if( len % POLARSSL_MEMORY_ALIGN_MULTIPLE )
+    {
+        len -= len % POLARSSL_MEMORY_ALIGN_MULTIPLE;
+        len += POLARSSL_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(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: block in free_list but allocated "
+                                  "data\n" );
+#endif
+        exit( 1 );
+    }
+
+#if defined(POLARSSL_MEMORY_DEBUG)
+    heap.malloc_count++;
+#endif
+
+    // Found location, split block if > memory_header + 4 room left
+    //
+    if( cur->size - len < sizeof(memory_header) +
+                          POLARSSL_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(POLARSSL_MEMORY_DEBUG)
+        heap.total_used += cur->size;
+        if( heap.total_used > heap.maximum_used)
+            heap.maximum_used = heap.total_used;
+#endif
+#if defined(POLARSSL_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 & MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 )
+            exit( 1 );
+
+        return ( (unsigned char *) cur ) + sizeof(memory_header);
+    }
+
+    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(POLARSSL_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(POLARSSL_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(POLARSSL_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 & MEMORY_VERIFY_ALLOC ) && verify_chain() != 0 )
+        exit( 1 );
+
+    return ( (unsigned char *) cur ) + sizeof(memory_header);
+}
+
+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(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: polarssl_free() outside of managed "
+                                  "space\n" );
+#endif
+        exit( 1 );
+    }
+
+    p -= sizeof(memory_header);
+    hdr = (memory_header *) p;
+
+    if( verify_header( hdr ) != 0 )
+        exit( 1 );
+
+    if( hdr->alloc != 1 )
+    {
+#if defined(POLARSSL_MEMORY_DEBUG)
+        polarssl_fprintf( stderr, "FATAL: polarssl_free() on unallocated "
+                                  "data\n" );
+#endif
+        exit( 1 );
+    }
+
+    hdr->alloc = 0;
+
+#if defined(POLARSSL_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(POLARSSL_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(POLARSSL_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(POLARSSL_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(POLARSSL_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;
+        heap.first_free->prev_free = hdr;
+        heap.first_free = hdr;
+    }
+
+#if defined(POLARSSL_MEMORY_BACKTRACE)
+    hdr->trace = NULL;
+    hdr->trace_count = 0;
+#endif
+
+    if( ( heap.verify & MEMORY_VERIFY_FREE ) && verify_chain() != 0 )
+        exit( 1 );
+}
+
+void memory_buffer_set_verify( int verify )
+{
+    heap.verify = verify;
+}
+
+int memory_buffer_alloc_verify()
+{
+    return verify_chain();
+}
+
+#if defined(POLARSSL_MEMORY_DEBUG)
+void memory_buffer_alloc_status()
+{
+    polarssl_fprintf( stderr,
+                      "Current use: %u blocks / %u bytes, max: %u blocks / "
+                      "%u bytes (total %u bytes), malloc / free: %u / %u\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.malloc_count, heap.free_count );
+
+    if( heap.first->next == NULL )
+        polarssl_fprintf( stderr, "All memory de-allocated in stack buffer\n" );
+    else
+    {
+        polarssl_fprintf( stderr, "Memory currently allocated:\n" );
+        debug_chain();
+    }
+}
+#endif /* POLARSSL_MEMORY_DEBUG */
+
+#if defined(POLARSSL_THREADING_C)
+static void *buffer_alloc_malloc_mutexed( size_t len )
+{
+    void *buf;
+    polarssl_mutex_lock( &heap.mutex );
+    buf = buffer_alloc_malloc( len );
+    polarssl_mutex_unlock( &heap.mutex );
+    return( buf );
+}
+
+static void buffer_alloc_free_mutexed( void *ptr )
+{
+    polarssl_mutex_lock( &heap.mutex );
+    buffer_alloc_free( ptr );
+    polarssl_mutex_unlock( &heap.mutex );
+}
+#endif /* POLARSSL_THREADING_C */
+
+int memory_buffer_alloc_init( unsigned char *buf, size_t len )
+{
+    memset( &heap, 0, sizeof(buffer_alloc_ctx) );
+    memset( buf, 0, len );
+
+#if defined(POLARSSL_THREADING_C)
+    polarssl_mutex_init( &heap.mutex );
+    platform_set_malloc_free( buffer_alloc_malloc_mutexed,
+                              buffer_alloc_free_mutexed );
+#else
+    platform_set_malloc_free( buffer_alloc_malloc, buffer_alloc_free );
+#endif
+
+    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;
+    return( 0 );
+}
+
+void memory_buffer_alloc_free()
+{
+#if defined(POLARSSL_THREADING_C)
+    polarssl_mutex_free( &heap.mutex );
+#endif
+    memset( &heap, 0, sizeof(buffer_alloc_ctx) );
+}
+
+#endif /* POLARSSL_MEMORY_BUFFER_ALLOC_C */
+
+