drivers: wifi: simplelink: Implement offloaded getaddrinfo()

This offloads the getaddrinfo() socket operation to the
simplelink WiFi driver, via a socket_offload hook.

This was validated using http_get on cc3220sf_launchxl.

Also implements freeaddrinfo().

Signed-off-by: Gil Pitney <gil.pitney@linaro.org>

drivers/wifi/simplelink/simplelink.c

@@ -229,6 +229,7 @@ static void simplelink_iface_init(struct net_if *iface)
 #ifdef CONFIG_NET_SOCKETS_OFFLOAD
 	/* Direct socket offload: */
 	socket_offload_register(&simplelink_ops);
+	simplelink_sockets_init();
 #endif
 
 }

drivers/wifi/simplelink/simplelink_sockets.c

@@ -7,6 +7,9 @@
 #include "simplelink_log.h"
 LOG_MODULE_DECLARE(LOG_MODULE_NAME);
 
+#include <stdlib.h>
+#include <limits.h>
+
 #include <zephyr.h>
 /* Define sockaddr, etc, before simplelink.h */
 #include <net/socket_offload.h>
@@ -15,6 +18,9 @@ LOG_MODULE_DECLARE(LOG_MODULE_NAME);
 #include <ti/drivers/net/wifi/source/driver.h>
 #include "simplelink_support.h"
 
+/* Mutex for getaddrinfo() calls: */
+K_MUTEX_DEFINE(ga_mutex);
+
 static int simplelink_socket(int family, int type, int proto)
 {
 	int retval;
@@ -509,22 +515,121 @@ exit:
 	return _SlDrvSetErrno(retval);
 }
 
+/*
+ * Later SimpleLink SDK versions implement the full getaddrinfo semantics,
+ * returning potentially multiple IP addresses.
+ * This version implements a simple gethostbyname() API.
+ */
 static int simplelink_getaddrinfo(const char *node, const char *service,
 				  const struct addrinfo *hints,
 				  struct addrinfo **res)
 {
-	ARG_UNUSED(node);
-	ARG_UNUSED(service);
-	ARG_UNUSED(hints);
-	ARG_UNUSED(res);
+	_u8 sl_family = SL_AF_INET;
+	unsigned long port = 0;
+	int socktype = SOCK_STREAM;
+	int proto = IPPROTO_TCP;
+	struct addrinfo *ai;
+	struct sockaddr *ai_addr;
+	_i16 retval;
+	_u32 ipaddr[4];
 
-	errno = ENOTSUP;
-	return EAI_SYSTEM;
+	/* Check args: */
+	if (!node && !service) {
+		retval = EAI_NONAME;
+		goto exit;
+	}
+	if (service) {
+		port = strtol(service, NULL, 10);
+		if (port < 1 || port > USHRT_MAX) {
+			retval = EAI_SERVICE;
+			goto exit;
+		}
+	}
+	if (!res) {
+		retval = EAI_NONAME;
+		goto exit;
+	}
+
+	/* See if any hints for family; otherwise, default to AF_INET. */
+	if (hints) {
+		/* Note: SimpleLink SDK doesn't support AF_UNSPEC: */
+		sl_family = (hints->ai_family == AF_INET6 ?
+			     SL_AF_INET6 : SL_AF_INET);
+	}
+
+	/* Now, try to resolve host name: */
+	k_mutex_lock(&ga_mutex, K_FOREVER);
+	retval = sl_NetAppDnsGetHostByName((signed char *)node, strlen(node),
+					   ipaddr, sl_family);
+	k_mutex_unlock(&ga_mutex);
+
+	if (retval < 0) {
+		LOG_ERR("Could not resolve name: %s, retval: %d",
+			    node, retval);
+		retval = EAI_NONAME;
+		goto exit;
+	}
+
+	/* Allocate out res (addrinfo) struct.	Just one. */
+	*res = calloc(1, sizeof(struct addrinfo));
+	ai = *res;
+	if (!ai) {
+		retval = EAI_MEMORY;
+		goto exit;
+	} else {
+		/* Now, alloc the embedded sockaddr struct: */
+		ai_addr = calloc(1, sizeof(struct sockaddr));
+		if (!ai_addr) {
+			retval = EAI_MEMORY;
+			free(*res);
+			goto exit;
+		}
+	}
+
+	/* Now, fill in the fields of res (addrinfo struct): */
+	ai->ai_family = (sl_family == SL_AF_INET6 ? AF_INET6 : AF_INET);
+	if (hints) {
+		socktype = hints->ai_socktype;
+	}
+	ai->ai_socktype = socktype;
+
+	if (socktype == SOCK_DGRAM) {
+		proto = IPPROTO_UDP;
+	}
+	ai->ai_protocol = proto;
+
+	/* Fill sockaddr struct fields based on family: */
+	if (ai->ai_family == AF_INET) {
+		net_sin(ai_addr)->sin_family = ai->ai_family;
+		net_sin(ai_addr)->sin_addr.s_addr = htonl(ipaddr[0]);
+		net_sin(ai_addr)->sin_port = htons(port);
+		ai->ai_addrlen = sizeof(struct sockaddr_in);
+	} else {
+		net_sin6(ai_addr)->sin6_family = ai->ai_family;
+		net_sin6(ai_addr)->sin6_addr.s6_addr32[0] = htonl(ipaddr[0]);
+		net_sin6(ai_addr)->sin6_addr.s6_addr32[1] = htonl(ipaddr[1]);
+		net_sin6(ai_addr)->sin6_addr.s6_addr32[2] = htonl(ipaddr[2]);
+		net_sin6(ai_addr)->sin6_addr.s6_addr32[3] = htonl(ipaddr[3]);
+		net_sin6(ai_addr)->sin6_port = htons(port);
+		ai->ai_addrlen = sizeof(struct sockaddr_in6);
+	}
+	ai->ai_addr = ai_addr;
+
+exit:
+	return retval;
 }
 
 static void simplelink_freeaddrinfo(struct addrinfo *res)
 {
-	ARG_UNUSED(res);
+	__ASSERT_NO_MSG(res);
+
+	free(res->ai_addr);
+	free(res);
+}
+
+void simplelink_sockets_init(void)
+{
+	k_mutex_init(&ga_mutex);
 }
 
 const struct socket_offload simplelink_ops = {

drivers/wifi/simplelink/simplelink_sockets.h

@@ -12,6 +12,7 @@ extern "C" {
 #endif
 
 extern const struct socket_offload simplelink_ops;
+extern void simplelink_sockets_init(void);
 
 #ifdef __cplusplus
 }