mem_dbg.c

一个用于点对点传输加密的工具包源码

/* crypto/mem_dbg.c */
/* Copyright (C) 1995-1998 Eric Young ([e-mail])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([e-mail]).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson ([e-mail]).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young ([e-mail])"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson ([e-mail])"
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <stdlib.h>
#include <time.h>	
#include <openssl/crypto.h>
#include <openssl/buffer.h>
#include <openssl/bio.h>
#include <openssl/lhash.h>
#include "cryptlib.h"

static int mh_mode=CRYPTO_MEM_CHECK_OFF;
/* The state changes to CRYPTO_MEM_CHECK_ON | CRYPTO_MEM_CHECK_ENABLE
 * when the application asks for it (usually after library initialisation
 * for which no book-keeping is desired).
 *
 * State CRYPTO_MEM_CHECK_ON exists only temporarily when the library
 * thinks that certain allocations should not be checked (e.g. the data
 * structures used for memory checking).  It is not suitable as an initial
 * state: the library will unexpectedly enable memory checking when it
 * executes one of those sections that want to disable checking
 * temporarily.
 *
 * State CRYPTO_MEM_CHECK_ENABLE without ..._ON makes no sense whatsoever.
 */

static unsigned long order = 0; /* number of memory requests */
static LHASH *mh=NULL; /* hash-table of memory requests (address as key) */


typedef struct app_mem_info_st
/* For application-defined information (static C-string `info')
 * to be displayed in memory leak list.
 * Each thread has its own stack.  For applications, there is
 *   CRYPTO_push_info("...")     to push an entry,
 *   CRYPTO_pop_info()           to pop an entry,
 *   CRYPTO_remove_all_info()    to pop all entries.
 */
	{	
	unsigned long thread;
	const char *file;
	int line;
	const char *info;
	struct app_mem_info_st *next; /* tail of thread's stack */
	int references;
	} APP_INFO;

static LHASH *amih=NULL; /* hash-table with those app_mem_info_st's
                          * that are at the top of their thread's stack
                          * (with `thread' as key) */

typedef struct mem_st
/* memory-block description */
	{
	void *addr;
	int num;
	const char *file;
	int line;
	unsigned long thread;
	unsigned long order;
	time_t time;
	APP_INFO *app_info;
	} MEM;

static long options =             /* extra information to be recorded */
#if defined(CRYPTO_MDEBUG_TIME) || defined(CRYPTO_MDEBUG_ALL)
	V_CRYPTO_MDEBUG_TIME |
#endif
#if defined(CRYPTO_MDEBUG_THREAD) || defined(CRYPTO_MDEBUG_ALL)
	V_CRYPTO_MDEBUG_THREAD |
#endif
	0;


static unsigned long disabling_thread = 0;

int CRYPTO_mem_ctrl(int mode)
	{
	int ret=mh_mode;

	CRYPTO_w_lock(CRYPTO_LOCK_MALLOC);
	switch (mode)
		{
	/* for applications: */
	case CRYPTO_MEM_CHECK_ON: /* aka MemCheck_start() */
		mh_mode = CRYPTO_MEM_CHECK_ON|CRYPTO_MEM_CHECK_ENABLE;
		disabling_thread = 0;
		break;
	case CRYPTO_MEM_CHECK_OFF: /* aka MemCheck_stop() */
		mh_mode = 0;
		disabling_thread = 0;
		break;

	/* switch off temporarily (for library-internal use): */
	case CRYPTO_MEM_CHECK_DISABLE: /* aka MemCheck_off() */
		if (mh_mode & CRYPTO_MEM_CHECK_ON)
			{
			mh_mode&= ~CRYPTO_MEM_CHECK_ENABLE;
			if (disabling_thread != CRYPTO_thread_id()) /* otherwise we already have the MALLOC2 lock */
				{
				/* Long-time lock CRYPTO_LOCK_MALLOC2 must not be claimed while
				 * we're holding CRYPTO_LOCK_MALLOC, or we'll deadlock if
				 * somebody else holds CRYPTO_LOCK_MALLOC2 (and cannot release
				 * it because we block entry to this function).
				 * Give them a chance, first, and then claim the locks in
				 * appropriate order (long-time lock first).
				 */
				CRYPTO_w_unlock(CRYPTO_LOCK_MALLOC);
				/* Note that after we have waited for CRYPTO_LOCK_MALLOC2
				 * and CRYPTO_LOCK_MALLOC, we'll still be in the right
				 * "case" and "if" branch because MemCheck_start and
				 * MemCheck_stop may never be used while there are multiple
				 * OpenSSL threads. */
				CRYPTO_w_lock(CRYPTO_LOCK_MALLOC2);
				CRYPTO_w_lock(CRYPTO_LOCK_MALLOC);
				disabling_thread=CRYPTO_thread_id();
				}
			}
		break;
	case CRYPTO_MEM_CHECK_ENABLE: /* aka MemCheck_on() */
		if (mh_mode & CRYPTO_MEM_CHECK_ON)
			{
			mh_mode|=CRYPTO_MEM_CHECK_ENABLE;
			if (disabling_thread != 0)
				{
				disabling_thread=0;
				CRYPTO_w_unlock(CRYPTO_LOCK_MALLOC2);
				}
			}
		break;

	default:
		break;
		}
	CRYPTO_w_unlock(CRYPTO_LOCK_MALLOC);
	return(ret);
	}

int CRYPTO_is_mem_check_on(void)
	{
	int ret = 0;

	if (mh_mode & CRYPTO_MEM_CHECK_ON)
		{
		CRYPTO_w_lock(CRYPTO_LOCK_MALLOC);

		ret = (mh_mode & CRYPTO_MEM_CHECK_ENABLE)
			&& disabling_thread != CRYPTO_thread_id();

		CRYPTO_w_unlock(CRYPTO_LOCK_MALLOC);
		}
	return(ret);
	}	


void CRYPTO_dbg_set_options(long bits)
	{
	options = bits;
	}

long CRYPTO_dbg_get_options(void)
	{
	return options;
	}

static int mem_cmp(MEM *a, MEM *b)
	{
	return((char *)a->addr - (char *)b->addr);
	}

static unsigned long mem_hash(MEM *a)
	{
	unsigned long ret;

	ret=(unsigned long)a->addr;

	ret=ret*17851+(ret>>14)*7+(ret>>4)*251;
	return(ret);
	}

static int app_info_cmp(APP_INFO *a, APP_INFO *b)
	{
	return(a->thread != b->thread);
	}

static unsigned long app_info_hash(APP_INFO *a)
	{
	unsigned long ret;

	ret=(unsigned long)a->thread;

	ret=ret*17851+(ret>>14)*7+(ret>>4)*251;
	return(ret);
	}

static APP_INFO *pop_info()
	{
	APP_INFO tmp;
	APP_INFO *ret = NULL;

	if (amih != NULL)
		{
		tmp.thread=CRYPTO_thread_id();
		if ((ret=(APP_INFO *)lh_delete(amih,&tmp)) != NULL)
			{
			APP_INFO *next=ret->next;

			if (next != NULL)
				{
				next->references++;
				lh_insert(amih,(char *)next);
				}
#ifdef LEVITTE_DEBUG
			if (ret->thread != tmp.thread)
				{
				fprintf(stderr, "pop_info(): deleted info has other thread ID (%lu) than the current thread (%lu)!!!!\n",
					ret->thread, tmp.thread);
				abort();
				}
#endif
			if (--(ret->references) <= 0)
				{
				ret->next = NULL;
				if (next != NULL)
					next->references--;
				OPENSSL_free(ret);
				}
			}
		}
	return(ret);
	}

int CRYPTO_push_info_(const char *info, const char *file, int line)
	{
	APP_INFO *ami, *amim;
	int ret=0;

	if (is_MemCheck_on())
		{
		MemCheck_off(); /* obtains CRYPTO_LOCK_MALLOC2 */

		if ((ami = (APP_INFO *)OPENSSL_malloc(sizeof(APP_INFO))) == NULL)
			{
			ret=0;
			goto err;
			}
		if (amih == NULL)
			{
			if ((amih=lh_new(app_info_hash,app_info_cmp)) == NULL)
				{
				OPENSSL_free(ami);
				ret=0;
				goto err;
				}
			}

		ami->thread=CRYPTO_thread_id();
		ami->file=file;
		ami->line=line;
		ami->info=info;
		ami->references=1;
		ami->next=NULL;

		if ((amim=(APP_INFO *)lh_insert(amih,(char *)ami)) != NULL)
			{
#ifdef LEVITTE_DEBUG
			if (ami->thread != amim->thread)
				{
				fprintf(stderr, "CRYPTO_push_info(): previous info has other thread ID (%lu) than the current thread (%lu)!!!!\n",
					amim->thread, ami->thread);
				abort();
				}
#endif
			ami->next=amim;
			}
 err:
		MemCheck_on(); /* releases CRYPTO_LOCK_MALLOC2 */
		}

	return(ret);
	}

int CRYPTO_pop_info(void)
	{
	int ret=0;

	if (is_MemCheck_on()) /* _must_ be true, or something went severely wrong */
		{
		MemCheck_off(); /* obtains CRYPTO_LOCK_MALLOC2 */

		ret=(pop_info() != NULL);

		MemCheck_on(); /* releases CRYPTO_LOCK_MALLOC2 */
		}
	return(ret);
	}

int CRYPTO_remove_all_info(void)
	{
	int ret=0;

	if (is_MemCheck_on()) /* _must_ be true */
		{
		MemCheck_off(); /* obtains CRYPTO_LOCK_MALLOC2 */

		while(pop_info() != NULL)
			ret++;

		MemCheck_on(); /* releases CRYPTO_LOCK_MALLOC2 */
		}