1 files changed, 540 insertions, 0 deletions
diff --git a/src/charon/lib/utils/leak_detective.c b/src/charon/lib/utils/leak_detective.c
new file mode 100644
index 000000000..780ba4c05
--- /dev/null
+++ b/src/charon/lib/utils/leak_detective.c
@@ -0,0 +1,540 @@
+/**
+ * @file leak_detective.c
+ * 
+ * @brief Allocation hooks to find memory leaks.
+ */
+
+/*
+ * Copyright (C) 2006 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include <stddef.h>
+#include <string.h>
+#include <stdio.h>
+#include <malloc.h>
+#include <execinfo.h>
+#include <signal.h> 
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <dlfcn.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <pthread.h>
+
+#include "leak_detective.h"
+
+#include <types.h>
+#include <utils/logger_manager.h>
+
+#ifdef LEAK_DETECTIVE
+
+/**
+ * Magic value which helps to detect memory corruption
+ */
+#define MEMORY_HEADER_MAGIC 0xF1367ADF
+
+static void install_hooks(void);
+static void uninstall_hooks(void);
+static void *malloc_hook(size_t, const void *);
+static void *realloc_hook(void *, size_t, const void *);
+static void free_hook(void*, const void *);
+static void load_excluded_functions();
+
+typedef struct memory_header_t memory_header_t;
+
+/**
+ * Header which is prepended to each allocated memory block
+ */
+struct memory_header_t {
+	/**
+	 * Magci byte which must(!) hold MEMORY_HEADER_MAGIC
+	 */
+	u_int32_t magic;
+	
+	/**
+	 * Number of bytes following after the header
+	 */
+	size_t bytes;
+	
+	/**
+	 * Stack frames at the time of allocation
+	 */
+	void *stack_frames[STACK_FRAMES_COUNT];
+	
+	/**
+	 * Number of stacks frames obtained in stack_frames
+	 */
+	int stack_frame_count;
+	
+	/**
+	 * Pointer to previous entry in linked list
+	 */
+	memory_header_t *previous;
+	
+	/**
+	 * Pointer to next entry in linked list
+	 */
+	memory_header_t *next;
+};
+
+/**
+ * first mem header is just a dummy to chain 
+ * the others on it...
+ */
+static memory_header_t first_header = {
+	magic: MEMORY_HEADER_MAGIC,
+	bytes: 0,
+	stack_frame_count: 0,
+	previous: NULL,
+	next: NULL
+};
+
+/**
+ * logger for the leak detective
+ */
+static logger_t *logger;
+
+/**
+ * standard hooks, used to temparily remove hooking
+ */
+static void *old_malloc_hook, *old_realloc_hook, *old_free_hook;
+
+/**
+ * are the hooks currently installed? 
+ */
+static bool installed = FALSE;
+
+/**
+ * Mutex to exclusivly uninstall hooks, access heap list
+ */
+static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+
+
+/**
+ * log stack frames queried by backtrace()
+ * TODO: Dump symbols of static functions!!!
+ */
+static void log_stack_frames(void **stack_frames, int stack_frame_count)
+{
+	char **strings;
+	size_t i;
+
+	strings = backtrace_symbols (stack_frames, stack_frame_count);
+
+	logger->log(logger, ERROR, "  dumping %d stack frame addresses.", stack_frame_count);
+
+	for (i = 0; i < stack_frame_count; i++)
+	{
+		logger->log(logger, ERROR, "    %s", strings[i]);
+	}
+	free (strings);
+}
+
+/**
+ * Report leaks at library destruction
+ */
+void report_leaks()
+{
+	memory_header_t *hdr;
+	int leaks = 0;
+	
+	/* reaquire a logger is necessary, this will force ((destructor))
+	* order to work correctly */
+	logger = logger_manager->get_logger(logger_manager, LEAK_DETECT);
+	for (hdr = first_header.next; hdr != NULL; hdr = hdr->next)
+	{
+		logger->log(logger, ERROR, "Leak (%d bytes at %p)", hdr->bytes, hdr + 1);
+		log_stack_frames(hdr->stack_frames, hdr->stack_frame_count);
+		leaks++;
+	}
+		
+	switch (leaks)
+	{
+		case 0:
+			logger->log(logger, CONTROL, "No leaks detected");
+			break;
+		case 1:
+			logger->log(logger, ERROR, "One leak detected");
+			break;
+		default:
+			logger->log(logger, ERROR, "%d leaks detected", leaks);
+			break;
+	}
+}
+
+/**
+ * Installs the malloc hooks, enables leak detection
+ */
+static void install_hooks()
+{
+	if (!installed)
+	{
+		old_malloc_hook = __malloc_hook;
+		old_realloc_hook = __realloc_hook;
+		old_free_hook = __free_hook;
+		__malloc_hook = malloc_hook;
+		__realloc_hook = realloc_hook;
+		__free_hook = free_hook;
+		installed = TRUE;
+	}
+}
+
+/**
+ * Uninstalls the malloc hooks, disables leak detection
+ */
+static void uninstall_hooks()
+{
+	if (installed)
+	{
+		__malloc_hook = old_malloc_hook;
+		__free_hook = old_free_hook;
+		__realloc_hook = old_realloc_hook;
+		installed = FALSE;
+	}
+}
+
+/**
+ * Hook function for malloc()
+ */
+void *malloc_hook(size_t bytes, const void *caller)
+{
+	memory_header_t *hdr;
+	
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	hdr = malloc(bytes + sizeof(memory_header_t));
+	
+	hdr->magic = MEMORY_HEADER_MAGIC;
+	hdr->bytes = bytes;
+	hdr->stack_frame_count = backtrace(hdr->stack_frames, STACK_FRAMES_COUNT);
+	
+	/* insert at the beginning of the list */
+	hdr->next = first_header.next;
+	if (hdr->next)
+	{
+		hdr->next->previous = hdr;
+	}
+	hdr->previous = &first_header;
+	first_header.next = hdr;
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return hdr + 1;
+}
+
+/**
+ * Hook function for free()
+ */
+void free_hook(void *ptr, const void *caller)
+{
+	void *stack_frames[STACK_FRAMES_COUNT];
+	int stack_frame_count;
+	memory_header_t *hdr = ptr - sizeof(memory_header_t);
+	
+	/* allow freeing of NULL */
+	if (ptr == NULL)
+	{
+		return;
+	}
+	
+	pthread_mutex_lock(&mutex);
+	if (hdr->magic != MEMORY_HEADER_MAGIC)
+	{
+		pthread_mutex_unlock(&mutex);
+		/* TODO: since pthread_join cannot be excluded cleanly, we are not whining about bad frees */
+		return;
+		logger->log(logger, ERROR, "freeing of invalid memory (%p)", ptr);
+		stack_frame_count = backtrace(stack_frames, STACK_FRAMES_COUNT);
+		log_stack_frames(stack_frames, stack_frame_count);
+		return;
+	}
+	/* remove magic from hdr */
+	hdr->magic = 0;
+	
+	/* remove item from list */
+	if (hdr->next)
+	{
+		hdr->next->previous = hdr->previous;
+	}
+	hdr->previous->next = hdr->next;
+	
+	uninstall_hooks();
+	free(hdr);
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+}
+
+/**
+ * Hook function for realloc()
+ */
+void *realloc_hook(void *old, size_t bytes, const void *caller)
+{
+	void *new;
+	memory_header_t *hdr = old - sizeof(memory_header_t);
+	void *stack_frames[STACK_FRAMES_COUNT];
+	int stack_frame_count;
+	
+	/* allow reallocation of NULL */
+	if (old == NULL)
+	{
+		return malloc_hook(bytes, caller);
+	}
+	if (hdr->magic != MEMORY_HEADER_MAGIC)
+	{
+		logger->log(logger, ERROR, "reallocation of invalid memory (%p)", old);
+		stack_frame_count = backtrace(stack_frames, STACK_FRAMES_COUNT);
+		log_stack_frames(stack_frames, stack_frame_count);
+		kill(getpid(), SIGKILL);
+		return NULL;
+	}
+	
+	/* malloc and free is done with hooks */
+	new = malloc_hook(bytes, caller);
+	memcpy(new, old, min(bytes, hdr->bytes));
+	free_hook(old, caller);
+	
+	return new;
+}
+
+
+/**
+ * Setup leak detective
+ */
+void leak_detective_init()
+{
+	logger = logger_manager->get_logger(logger_manager, LEAK_DETECT);
+	load_excluded_functions();
+	install_hooks();
+}
+
+/**
+ * Clean up leak detective
+ */
+void leak_detective_cleanup()
+{
+	uninstall_hooks();
+	report_leaks();
+}
+
+
+/**
+ * The following glibc functions are excluded from leak detection, since
+ * they use static allocated buffers or other ugly allocation hacks.
+ * For this to work, the linker must link libstrongswan preferred to
+ * the other (overriden) libs.
+ */
+struct excluded_function {
+	char *lib_name;
+	char *function_name;
+	void *handle;
+	void *lib_function;
+} excluded_functions[] = {
+	{"libc.so.6", 		"inet_ntoa", 			NULL, NULL},
+	{"libpthread.so.0", "pthread_create", 		NULL, NULL},
+	{"libpthread.so.0", "pthread_cancel", 		NULL, NULL},
+	{"libpthread.so.0", "pthread_join", 		NULL, NULL},
+	{"libpthread.so.0", "_pthread_cleanup_push",NULL, NULL},
+	{"libpthread.so.0", "_pthread_cleanup_pop",	NULL, NULL},
+	{"libc.so.6", 		"mktime", 				NULL, NULL},
+	{"libc.so.6", 		"vsyslog", 				NULL, NULL},
+	{"libc.so.6", 		"strerror", 			NULL, NULL},
+};
+#define INET_NTOA				0
+#define PTHREAD_CREATE			1
+#define PTHREAD_CANCEL			2
+#define PTHREAD_JOIN			3
+#define PTHREAD_CLEANUP_PUSH	4
+#define PTHREAD_CLEANUP_POP		5
+#define MKTIME					6
+#define VSYSLOG					7
+#define STRERROR				8
+
+
+/**
+ * Load libraries and function pointers for excluded functions
+ */
+static void load_excluded_functions()
+{
+	int i;
+	
+	for (i = 0; i < sizeof(excluded_functions)/sizeof(struct excluded_function); i++)
+	{
+		void *handle, *function;
+		handle = dlopen(excluded_functions[i].lib_name, RTLD_LAZY);
+		if (handle == NULL)
+		{
+			kill(getpid(), SIGSEGV);
+		}
+		
+		function = dlsym(handle, excluded_functions[i].function_name);
+		
+		if (function  == NULL)
+		{
+			dlclose(handle);
+			kill(getpid(), SIGSEGV);
+		}
+		excluded_functions[i].handle = handle;
+		excluded_functions[i].lib_function = function;
+	}
+}
+
+char *inet_ntoa(struct in_addr in)
+{
+	char *(*_inet_ntoa)(struct in_addr) = excluded_functions[INET_NTOA].lib_function;
+	char *result;
+	
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	
+	result = _inet_ntoa(in);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return result;
+}
+
+int pthread_create(pthread_t *__restrict __threadp, __const pthread_attr_t *__restrict __attr, 
+					void *(*__start_routine) (void *), void *__restrict __arg)
+{
+	int (*_pthread_create) (pthread_t *__restrict __threadp,
+						__const pthread_attr_t *__restrict __attr,
+						void *(*__start_routine) (void *),
+						void *__restrict __arg) = excluded_functions[PTHREAD_CREATE].lib_function;
+	int result;
+	
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	
+	result = _pthread_create(__threadp, __attr, __start_routine, __arg);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return result;
+}
+
+
+int pthread_cancel(pthread_t __th)
+{
+	int (*_pthread_cancel) (pthread_t) = excluded_functions[PTHREAD_CANCEL].lib_function;
+	int result;
+	
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	
+	result = _pthread_cancel(__th);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return result;
+}
+
+// /* TODO: join has probs, since it dellocates memory 
+//  * allocated (somewhere) with leak_detective :-(.
+//  * We should exclude all pthread_ functions to fix it !? */
+// int pthread_join(pthread_t __th, void **__thread_return)
+// {
+// 	int (*_pthread_join) (pthread_t, void **) = excluded_functions[PTHREAD_JOIN].lib_function;
+// 	int result;
+// 	
+// 	pthread_mutex_lock(&mutex);
+// 	uninstall_hooks();
+// 	
+// 	result = _pthread_join(__th, __thread_return);
+// 	
+// 	install_hooks();
+// 	pthread_mutex_unlock(&mutex);
+// 	return result;
+// }
+// 
+// void _pthread_cleanup_push (struct _pthread_cleanup_buffer *__buffer,
+// 								   void (*__routine) (void *),
+// 								   void *__arg)
+// {
+// 	int (*__pthread_cleanup_push) (struct _pthread_cleanup_buffer *__buffer,
+// 									void (*__routine) (void *),
+// 									void *__arg) = 
+// 			excluded_functions[PTHREAD_CLEANUP_PUSH].lib_function;
+// 	
+// 	pthread_mutex_lock(&mutex);
+// 	uninstall_hooks();
+// 	
+// 	__pthread_cleanup_push(__buffer, __routine, __arg);
+// 	
+// 	install_hooks();
+// 	pthread_mutex_unlock(&mutex);
+// 	return;
+// }
+// 	
+// void _pthread_cleanup_pop (struct _pthread_cleanup_buffer *__buffer, int __execute)
+// {
+// 	int (*__pthread_cleanup_pop) (struct _pthread_cleanup_buffer *__buffer, int __execute) = 
+// 			excluded_functions[PTHREAD_CLEANUP_POP].lib_function;
+// 	
+// 	pthread_mutex_lock(&mutex);
+// 	uninstall_hooks();
+// 	
+// 	__pthread_cleanup_pop(__buffer, __execute);
+// 	
+// 	install_hooks();
+// 	pthread_mutex_unlock(&mutex);
+// 	return;
+// }
+
+time_t mktime(struct tm *tm)
+{
+	time_t (*_mktime)(struct tm *tm) = excluded_functions[MKTIME].lib_function;
+	time_t result;
+
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+		
+	result = _mktime(tm);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return result;
+}
+
+void vsyslog (int __pri, __const char *__fmt, __gnuc_va_list __ap)
+{
+	void (*_vsyslog) (int __pri, __const char *__fmt, __gnuc_va_list __ap) = excluded_functions[VSYSLOG].lib_function;
+
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	
+	_vsyslog(__pri, __fmt, __ap);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return;
+}
+
+
+
+char *strerror(int errnum)
+{
+	char* (*_strerror) (int) = excluded_functions[STRERROR].lib_function;
+	char *result;
+
+	pthread_mutex_lock(&mutex);
+	uninstall_hooks();
+	
+	result = _strerror(errnum);
+	
+	install_hooks();
+	pthread_mutex_unlock(&mutex);
+	return result;
+}
+
+#endif /* LEAK_DETECTION */