net: Add net_context to compilation

Network context defines network endpoints a.k.a sockets.

Change-Id: Ib1fab03f0862b298a441a79a4f4173f18a8260cb
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>

net/yaip/Kconfig

@@ -96,6 +96,13 @@ config NET_NBUF_DATA_SIZE
 	  In order to be able to receive at least full IPv6 packet which
 	  has a size of 1280 bytes, the one should allocate 16 fragments here.
 
+config CONFIG_NET_MAX_CONTEXTS
+	int "Number of network contexts to allocate"
+	default 6
+	help
+	  Each network context is used to describe a network 5-tuple that
+	  is used when listening or sending network traffic.
+
 config NET_SLIP
        bool "Use SLIP connectivity with Qemu"
        default n

net/yaip/Makefile

@@ -1,4 +1,5 @@
 ccflags-y += -I${srctree}/net/ip
 obj-y = net_core.o \
 	net_if.o \
+	net_context.o \
 	nbuf.o

net/yaip/net_context.c

@@ -0,0 +1,164 @@
+/** @file
+ @brief Network context API
+
+ An API for applications to define a network connection.
+ */
+
+/*
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <nanokernel.h>
+#include <string.h>
+#include <errno.h>
+#include <stdbool.h>
+
+#include <net/net_ip.h>
+#include <net/net_context.h>
+
+/* Override this in makefile if needed */
+#if defined(CONFIG_NET_MAX_CONTEXTS)
+#define NET_MAX_CONTEXT CONFIG_NET_MAX_CONTEXTS
+#else
+#define NET_MAX_CONTEXT 6
+#endif
+
+static struct net_context contexts[NET_MAX_CONTEXT];
+static struct nano_sem contexts_lock;
+
+static void context_sem_give(struct nano_sem *chan)
+{
+	switch (sys_execution_context_type_get()) {
+	case NANO_CTX_FIBER:
+		nano_fiber_sem_give(chan);
+		break;
+	case NANO_CTX_TASK:
+		nano_task_sem_give(chan);
+		break;
+	case NANO_CTX_ISR:
+	default:
+		/* Invalid context type */
+		break;
+	}
+}
+
+static int context_port_used(enum ip_protocol ip_proto, uint16_t local_port,
+			     const struct net_addr *local_addr)
+
+{
+	int i;
+
+	for (i = 0; i < NET_MAX_CONTEXT; i++) {
+		if (contexts[i].tuple.ip_proto == ip_proto &&
+		    contexts[i].tuple.local_port == local_port &&
+		    !memcmp(&contexts[i].tuple.local_addr, local_addr,
+			   sizeof(struct net_addr))) {
+			return -EEXIST;
+		}
+	}
+
+	return 0;
+}
+
+struct net_context *net_context_get(enum ip_protocol ip_proto,
+				    const struct net_addr *remote_addr,
+				    uint16_t remote_port,
+				    struct net_addr *local_addr,
+				    uint16_t local_port)
+{
+#ifdef CONFIG_NET_IPV6
+	const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
+#endif
+	int i;
+	struct net_context *context = NULL;
+
+	/* User must provide storage for the local address. */
+	if (!local_addr) {
+		return NULL;
+	}
+
+#if defined(CONFIG_NET_IPV6)
+	if (memcmp(&local_addr->in6_addr, &in6addr_any,
+		   sizeof(in6addr_any)) == 0) {
+		/* FIXME */
+	}
+#endif
+#if defined(CONFIG_NET_IPV4)
+	if (local_addr->in_addr.s_addr == INADDR_ANY) {
+		/* FIXME */
+	}
+#endif
+
+	nano_sem_take(&contexts_lock, TICKS_UNLIMITED);
+
+	if (local_port) {
+		if (context_port_used(ip_proto, local_port, local_addr) < 0) {
+			return NULL;
+		}
+	} else {
+		do {
+			local_port = sys_rand32_get() | 0x8000;
+		} while (context_port_used(ip_proto, local_port,
+					   local_addr) == -EEXIST);
+	}
+
+	for (i = 0; i < NET_MAX_CONTEXT; i++) {
+		if (!contexts[i].tuple.ip_proto) {
+			contexts[i].tuple.ip_proto = ip_proto;
+			contexts[i].tuple.remote_addr = (struct net_addr *)remote_addr;
+			contexts[i].tuple.remote_port = remote_port;
+			contexts[i].tuple.local_addr = (struct net_addr *)local_addr;
+			contexts[i].tuple.local_port = local_port;
+			context = &contexts[i];
+			break;
+		}
+	}
+
+	context_sem_give(&contexts_lock);
+
+	return context;
+}
+
+void net_context_put(struct net_context *context)
+{
+	if (!context) {
+		return;
+	}
+
+	nano_sem_take(&contexts_lock, TICKS_UNLIMITED);
+
+	if (context->tuple.ip_proto == IPPROTO_UDP) {
+		/* FIXME */
+	}
+
+	memset(&context->tuple, 0, sizeof(context->tuple));
+
+	context_sem_give(&contexts_lock);
+}
+
+void net_context_init(void)
+{
+	int i;
+
+	nano_sem_init(&contexts_lock);
+
+	memset(contexts, 0, sizeof(contexts));
+
+	for (i = 0; i < NET_MAX_CONTEXT; i++) {
+		nano_fifo_init(&contexts[i].rx_queue);
+	}
+
+	context_sem_give(&contexts_lock);
+}

net/yaip/net_core.c

@@ -133,6 +133,8 @@ static int net_init(struct device *unused)
 
 	net_if_init();
 
+	net_context_init();
+
 	return network_initialization();
 }
 

net/yaip/net_private.h

@@ -24,3 +24,4 @@
 
 extern void net_nbuf_init(void);
 extern int net_if_init(void);
+extern void net_context_init(void);