SecureSocket: add OpenSSL locking.

This shoiuld make OpenSSL more thread safe and help with the random
network related crashes in Web+ (and anything else using SecureSocket
with more than one thread).

src/kits/network/libnetapi/SSL.cpp

@@ -1,5 +1,7 @@
 /*
  * Copyright 2011, Axel Dörfler, [email protected].
+ * Copyright 2014 Haiku, inc.
+ *
  * Distributed under the terms of the MIT License.
  */
 
@@ -8,6 +10,7 @@
 
 #include <openssl/ssl.h>
 #include <openssl/rand.h>
+#include <pthread.h>
 
 
 namespace BPrivate {
@@ -21,11 +24,46 @@ public:
 
 		int64 seed = find_thread(NULL) ^ system_time();
 		RAND_seed(&seed, sizeof(seed));
+
+		// Set callbacks required for thread-safe operation of OpenSSL.
+		sMutexBuf = new pthread_mutex_t[CRYPTO_num_locks()];
+		for (int i = 0; i < CRYPTO_num_locks(); i++)
+			pthread_mutex_init(&sMutexBuf[i], NULL);
+		CRYPTO_set_id_callback(_GetThreadId);
+		CRYPTO_set_locking_callback(_LockingFunction);
 	}
+
+	~SSL()
+	{
+		CRYPTO_set_id_callback(NULL);
+		CRYPTO_set_locking_callback(NULL);
+
+		for (int i = 0; i < CRYPTO_num_locks(); i++)
+			pthread_mutex_destroy(&sMutexBuf[i]);
+		delete sMutexBuf;
+	}
+
+private:
+	static void _LockingFunction(int mode, int n, const char * file, int line)
+	{
+		if (mode & CRYPTO_LOCK)
+			pthread_mutex_lock(&sMutexBuf[n]);
+		else
+			pthread_mutex_unlock(&sMutexBuf[n]);
+	}
+
+	static unsigned long _GetThreadId()
+	{
+		return find_thread(NULL);
+	}
+
+private:
+	static pthread_mutex_t* sMutexBuf;
 };
 
 
 static SSL sSSL;
+pthread_mutex_t* SSL::sMutexBuf;
 
 
 }	// namespace BPrivate