conntrackd: add support state-replication based on TCP

This patch adds support for TCP as protocol to replicate
state-changes between two daemons. Note that this only
makes sense with the notrack mode.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 75 insertions, 0 deletions

diff --git a/include/tcp.h b/include/tcp.h
new file mode 100644
index 0000000..1b1d391
--- /dev/null
+++ b/include/tcp.h
@@ -0,0 +1,75 @@
+#ifndef _TCP_H_
+#define _TCP_H_
+
+#include <stdint.h>
+#include <netinet/in.h>
+
+struct tcp_conf {
+	int ipproto;
+	int reuseaddr;
+	int checksum;
+	unsigned short port;
+	union {
+		struct {
+			struct in_addr inet_addr;
+		} ipv4;
+		struct {
+			struct in6_addr inet_addr6;
+			int scope_id;
+		} ipv6;
+	} server;
+	union {
+		struct in_addr inet_addr;
+		struct in6_addr inet_addr6;
+	} client;
+	int sndbuf;
+	int rcvbuf;
+};
+
+struct tcp_stats {
+	uint64_t bytes;
+	uint64_t messages;
+	uint64_t error;
+};
+
+enum tcp_sock_state {
+	TCP_SERVER_ACCEPTING,
+	TCP_SERVER_CONNECTED,
+	TCP_CLIENT_DISCONNECTED,
+	TCP_CLIENT_CONNECTED
+};
+
+struct tcp_sock {
+	int state;	/* enum tcp_sock_state */
+	int fd;
+	int client_fd;	/* only for the server side */
+	union {
+		struct sockaddr_in ipv4;
+		struct sockaddr_in6 ipv6;
+	} addr;
+	socklen_t sockaddr_len;
+	struct tcp_stats stats;
+};
+
+struct tcp_sock *tcp_server_create(struct tcp_conf *conf);
+void tcp_server_destroy(struct tcp_sock *m);
+
+struct tcp_sock *tcp_client_create(struct tcp_conf *conf);
+void tcp_client_destroy(struct tcp_sock *m);
+
+ssize_t tcp_send(struct tcp_sock *m, const void *data, int size);
+ssize_t tcp_recv(struct tcp_sock *m, void *data, int size);
+int tcp_accept(struct tcp_sock *m);
+
+int tcp_get_fd(struct tcp_sock *m);
+int tcp_isset(struct tcp_sock *m, fd_set *readfds);
+int tcp_accept_isset(struct tcp_sock *m, fd_set *readfds);
+
+int tcp_snprintf_stats(char *buf, size_t buflen, char *ifname,
+		       struct tcp_sock *s, struct tcp_sock *r);
+
+int tcp_snprintf_stats2(char *buf, size_t buflen, const char *ifname,
+			const char *status, int active,
+			struct tcp_stats *s, struct tcp_stats *r);
+
+#endif