[RFC 4/9] snet: introduce snet_core.c and snet.h

[Samir Bellabes <sam@synack.fr>]

this patch introduce snet_core.c, which provides main functions to start and
stop snet's subsystems :
	- snet_hooks	: LSM hooks
	- snet_netlink	: kernel-user communication (genetlink)
	- snet_event	: manages the table of protected syscalls
	- snet_verdict	: provides a wait queue for syscalls and manage verdicts
			  from userspace

Signed-off-by: Samir Bellabes <sam@synack.fr>
---
 security/snet/include/snet.h |   29 ++++++++++++++++
 security/snet/snet_core.c    |   77 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 106 insertions(+), 0 deletions(-)
 create mode 100644 security/snet/include/snet.h
 create mode 100644 security/snet/snet_core.c

diff --git a/security/snet/include/snet.h b/security/snet/include/snet.h
new file mode 100644
index 0000000..b664a47
--- /dev/null
+++ b/security/snet/include/snet.h
@@ -0,0 +1,29 @@
+#ifndef _SNET_H
+#define _SNET_H
+
+#include "snet_hooks.h"
+
+#define SNET_VERSION	0x1
+#define SNET_NAME	"snet"
+
+#define SNET_PRINTK(enable, fmt, arg...)			\
+	do {							\
+		if (enable)					\
+			printk(KERN_INFO "%s: %s: " fmt ,	\
+				SNET_NAME , __func__ ,		\
+				## arg);			\
+	} while (0)
+
+#ifdef CONFIG_SECURITY_SNET_DEBUG
+extern unsigned int snet_debug;
+#define snet_dbg(fmt, arg...)	SNET_PRINTK(snet_debug, fmt, ##arg)
+#else
+#define snet_dbg(fmt, arg...)
+#endif
+
+struct snet_event {
+	enum snet_syscall syscall;
+	u8 protocol;
+} __attribute__ ((packed));
+
+#endif /* _SNET_H */
diff --git a/security/snet/snet_core.c b/security/snet/snet_core.c
new file mode 100644
index 0000000..34b61e9
--- /dev/null
+++ b/security/snet/snet_core.c
@@ -0,0 +1,77 @@
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <net/genetlink.h>
+
+#include "snet.h"
+#include "snet_hooks.h"
+#include "snet_netlink.h"
+#include "snet_event.h"
+#include "snet_verdict.h"
+#include "snet_utils.h"
+
+unsigned int event_hash_size = 16;
+module_param(event_hash_size, uint, 0600);
+MODULE_PARM_DESC(event_hash_size, "Set the size of the event hash table");
+
+unsigned int verdict_hash_size = 16;
+module_param(verdict_hash_size, uint, 0600);
+MODULE_PARM_DESC(verdict_hash_size, "Set the size of the verdict hash table");
+
+unsigned int snet_verdict_delay = 5;
+module_param(snet_verdict_delay, uint, 0600);
+MODULE_PARM_DESC(snet_verdict_delay, "Set the timeout for verdicts in secs");
+
+unsigned int snet_verdict_policy = SNET_VERDICT_GRANT;	/* permissive by default */
+module_param(snet_verdict_policy, uint, 0600);
+MODULE_PARM_DESC(snet_verdict_policy, "Set the default verdict");
+
+#ifdef CONFIG_SECURITY_SNET_DEBUG
+unsigned int snet_debug;
+EXPORT_SYMBOL_GPL(snet_debug);
+module_param(snet_debug, bool, 0644);
+MODULE_PARM_DESC(snet_debug, "Enable debug messages");
+#endif
+
+void snet_core_exit(void)
+{
+	snet_netlink_exit();
+	snet_event_exit();
+	snet_hooks_exit();
+	snet_verdict_exit();
+	snet_dbg("stopped\n");
+}
+
+static __init int snet_init(void)
+{
+	int ret;
+
+	snet_dbg("initializing: event_hash_size=%u "
+		 "verdict_hash_size=%u verdict_delay=%usecs "
+		 "default_policy=%s\n",
+		 event_hash_size, verdict_hash_size, snet_verdict_delay,
+		 snet_verdict_name(snet_verdict_policy));
+
+	ret = snet_event_init();
+	if (ret < 0)
+		goto exit;
+
+	ret = snet_verdict_init();
+	if (ret < 0)
+		goto exit;
+
+	ret = snet_hooks_init();
+	if (ret < 0)
+		goto exit;
+
+	snet_dbg("started\n");
+	return 0;
+exit:
+	snet_core_exit();
+	return ret;
+}
+
+security_initcall(snet_init);
+
+MODULE_DESCRIPTION("snet - Security for NETwork syscalls");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Samir Bellabes <sam@synack.fr>");
-- 
1.6.3.3