net: Implement a new network stack

The old network stack has some bad limitations:

- network commands are required to call NetLoop() which only returns when
  the network layer wants to. Instead we now use a net_poll() function which
  returns after handling one packet (or immediately if no packet is
  available).
- There can be only one packet handler which makes it impossible to handle
  multiple connections
- CamelCaseMakesItHardToRead

The new network stack is implemented as a parallel universe. Currently all
commands still use the old stack. They are converted in subsequent patches.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 338 insertions, 3 deletions

diff --git a/include/net.h b/include/net.h
index de78293840..0ee7ecb8a6 100644
--- a/include/net.h
+++ b/include/net.h
@@ -15,6 +15,7 @@
 #include <driver.h>
 #include <linux/types.h>
 #include <param.h>
+#include <malloc.h>
 #include <asm/byteorder.h>	/* for nton* / ntoh* stuff */
 
 
@@ -186,8 +187,6 @@ typedef struct
 	uchar		ar_data[0];
 } ARP_t;
 
-#define ARP_HDR_SIZE	(8+20)		/* Size assuming ethernet	*/
-
 /*
  * ICMP stuff (just enough to handle (host) redirect messages)
  */
@@ -199,7 +198,7 @@ typedef struct
 #define ICMP_REDIR_NET		0	/* Redirect Net			*/
 #define ICMP_REDIR_HOST		1	/* Redirect Host		*/
 
-typedef struct icmphdr {
+typedef struct {
 	uchar		type;
 	uchar		code;
 	ushort		checksum;
@@ -415,4 +414,340 @@ void eth_set_current(struct eth_device *eth);
 struct eth_device *eth_get_current(void);
 struct eth_device *eth_get_byname(char *name);
 
+/*
+ *	Ethernet header
+ */
+struct ethernet {
+	uint8_t		et_dest[6];	/* Destination node		*/
+	uint8_t		et_src[6];	/* Source node			*/
+	uint16_t	et_protlen;	/* Protocol or length		*/
+} __attribute__ ((packed));
+
+#define ETHER_HDR_SIZE	14		/* Ethernet header size		*/
+
+#define PROT_IP		0x0800		/* IP protocol			*/
+#define PROT_ARP	0x0806		/* IP ARP protocol		*/
+#define PROT_RARP	0x8035		/* IP ARP protocol		*/
+#define PROT_VLAN	0x8100		/* IEEE 802.1q protocol		*/
+
+#define IPPROTO_ICMP	 1	/* Internet Control Message Protocol	*/
+#define IPPROTO_UDP	17	/* User Datagram Protocol		*/
+
+/*
+ *	Internet Protocol (IP) header.
+ */
+struct iphdr {
+	uint8_t		hl_v;
+	uint8_t		tos;
+	uint16_t	tot_len;
+	uint16_t	id;
+	uint16_t	frag_off;
+	uint8_t		ttl;
+	uint8_t		protocol;
+	uint16_t	check;
+	uint32_t	saddr;
+	uint32_t	daddr;
+	/* The options start here. */
+} __attribute__ ((packed));
+
+struct udphdr {
+	uint16_t	uh_sport;	/* source port */
+	uint16_t	uh_dport;	/* destination port */
+	uint16_t	uh_ulen;	/* udp length */
+	uint16_t	uh_sum;		/* udp checksum */
+} __attribute__ ((packed));
+
+/*
+ *	Address Resolution Protocol (ARP) header.
+ */
+struct arprequest
+{
+	uint16_t	ar_hrd;		/* Format of hardware address	*/
+#define ARP_ETHER	1		/* Ethernet  hardware address	*/
+	uint16_t	ar_pro;		/* Format of protocol address	*/
+	uint8_t		ar_hln;		/* Length of hardware address	*/
+	uint8_t		ar_pln;		/* Length of protocol address	*/
+	uint16_t	ar_op;		/* Operation			*/
+#define ARPOP_REQUEST	1		/* Request  to resolve  address	*/
+#define ARPOP_REPLY	2		/* Response to previous request	*/
+
+#define RARPOP_REQUEST	3		/* Request  to resolve  address	*/
+#define RARPOP_REPLY	4		/* Response to previous request */
+
+	/*
+	 * The remaining fields are variable in size, according to
+	 * the sizes above, and are defined as appropriate for
+	 * specific hardware/protocol combinations.
+	 */
+	uint8_t		ar_data[0];
+} __attribute__ ((packed));
+
+#define ARP_HDR_SIZE	(8 + 20)	/* Size assuming ethernet	*/
+
+/*
+ * ICMP stuff (just enough to handle (host) redirect messages)
+ */
+#define ICMP_ECHO_REPLY		0	/* Echo reply 			*/
+#define ICMP_REDIRECT		5	/* Redirect (change route)	*/
+#define ICMP_ECHO_REQUEST	8	/* Echo request			*/
+
+/* Codes for REDIRECT. */
+#define ICMP_REDIR_NET		0	/* Redirect Net			*/
+#define ICMP_REDIR_HOST		1	/* Redirect Host		*/
+
+struct icmphdr {
+	uint8_t		type;
+	uint8_t		code;
+	uint16_t	checksum;
+	union {
+		struct {
+			uint16_t	id;
+			uint16_t	sequence;
+		} echo;
+		uint32_t	gateway;
+		struct {
+			uint16_t	__unused;
+			uint16_t	mtu;
+		} frag;
+	} un;
+} __attribute__ ((packed));
+
+
+/*
+ * Maximum packet size; used to allocate packet storage.
+ * TFTP packets can be 524 bytes + IP header + ethernet header.
+ * Lets be conservative, and go for 38 * 16.  (Must also be
+ * a multiple of 32 bytes).
+ */
+#define PKTSIZE			1518
+
+/**********************************************************************/
+/*
+ *	Globals.
+ *
+ * Note:
+ *
+ * All variables of type IPaddr_t are stored in NETWORK byte order
+ * (big endian).
+ */
+
+extern unsigned char *NetRxPackets[PKTBUFSRX];/* Receive packets		*/
+
+void net_set_ip(IPaddr_t ip);
+void net_set_serverip(IPaddr_t ip);
+void net_set_netmask(IPaddr_t ip);
+void net_set_gateway(IPaddr_t ip);
+IPaddr_t net_get_ip(void);
+IPaddr_t net_get_serverip(void);
+
+/* Do the work */
+void net_poll(void);
+
+static inline struct iphdr *net_eth_to_iphdr(char *pkt)
+{
+	return (struct iphdr *)(pkt + ETHER_HDR_SIZE);
+}
+
+static inline struct udphdr *net_eth_to_udphdr(char *pkt)
+{
+	return (struct udphdr *)(net_eth_to_iphdr(pkt) + 1);
+}
+
+static inline struct icmphdr *net_eth_to_icmphdr(char *pkt)
+{
+	return (struct icmphdr *)(net_eth_to_iphdr(pkt) + 1);
+}
+
+static inline char *net_eth_to_icmp_payload(char *pkt)
+{
+	return (char *)(net_eth_to_icmphdr(pkt) + 1);
+}
+
+static inline char *net_eth_to_udp_payload(char *pkt)
+{
+	return (char *)(net_eth_to_udphdr(pkt) + 1);
+}
+
+static inline int net_eth_to_udplen(char *pkt)
+{
+	struct udphdr *udp = net_eth_to_udphdr(pkt);
+	return ntohs(udp->uh_ulen) - 8;
+}
+
+int net_checksum_ok(unsigned char *, int);	/* Return true if cksum OK	*/
+uint16_t net_checksum(unsigned char *, int);	/* Calculate the checksum	*/
+
+void NetReceive(unsigned char *, int);
+
+/* Print an IP address on the console */
+void print_IPaddr (IPaddr_t);
+
+/*
+ * The following functions are a bit ugly, but necessary to deal with
+ * alignment restrictions on ARM.
+ *
+ * We're using inline functions, which had the smallest memory
+ * footprint in our tests.
+ */
+/* return IP *in network byteorder* */
+static inline IPaddr_t net_read_ip(void *from)
+{
+	IPaddr_t ip;
+	memcpy((void*)&ip, from, sizeof(ip));
+	return ip;
+}
+
+/* return uint32 *in network byteorder* */
+static inline uint32_t net_read_uint32(uint32_t *from)
+{
+	ulong l;
+	memcpy((void*)&l, (void*)from, sizeof(l));
+	return l;
+}
+
+/* write IP *in network byteorder* */
+static inline void net_write_ip(void *to, IPaddr_t ip)
+{
+	memcpy(to, (void*)&ip, sizeof(ip));
+}
+
+/* copy IP */
+static inline void net_copy_ip(void *to, void *from)
+{
+	memcpy(to, from, sizeof(IPaddr_t));
+}
+
+/* copy ulong */
+static inline void net_copy_uint32(uint32_t *to, uint32_t *from)
+{
+	memcpy(to, from, sizeof(uint32_t));
+}
+
+/* Convert an IP address to a string */
+char *ip_to_string (IPaddr_t x, char *s);
+
+/* Convert a string to ip address */
+int string_to_ip(const char *s, IPaddr_t *ip);
+
+IPaddr_t getenv_ip(const char *name);
+int setenv_ip(const char *name, IPaddr_t ip);
+
+int string_to_ethaddr(const char *str, char *enetaddr);
+void ethaddr_to_string(const unsigned char *enetaddr, char *str);
+
+/**
+ * is_zero_ether_addr - Determine if give Ethernet address is all zeros.
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Return true if the address is all zeroes.
+ */
+static inline int is_zero_ether_addr(const u8 *addr)
+{
+	return !(addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | addr[5]);
+}
+
+/**
+ * is_multicast_ether_addr - Determine if the Ethernet address is a multicast.
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Return true if the address is a multicast address.
+ * By definition the broadcast address is also a multicast address.
+ */
+static inline int is_multicast_ether_addr(const u8 *addr)
+{
+	return (0x01 & addr[0]);
+}
+
+/**
+ * is_local_ether_addr - Determine if the Ethernet address is locally-assigned one (IEEE 802).
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Return true if the address is a local address.
+ */
+static inline int is_local_ether_addr(const u8 *addr)
+{
+	return (0x02 & addr[0]);
+}
+
+/**
+ * is_broadcast_ether_addr - Determine if the Ethernet address is broadcast
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Return true if the address is the broadcast address.
+ */
+static inline int is_broadcast_ether_addr(const u8 *addr)
+{
+	return (addr[0] & addr[1] & addr[2] & addr[3] & addr[4] & addr[5]) == 0xff;
+}
+
+/**
+ * is_valid_ether_addr - Determine if the given Ethernet address is valid
+ * @addr: Pointer to a six-byte array containing the Ethernet address
+ *
+ * Check that the Ethernet address (MAC) is not 00:00:00:00:00:00, is not
+ * a multicast address, and is not FF:FF:FF:FF:FF:FF.
+ *
+ * Return true if the address is valid.
+ */
+static inline int is_valid_ether_addr(const u8 *addr)
+{
+	/* FF:FF:FF:FF:FF:FF is a multicast address so we don't need to
+	 * explicitly check for it here. */
+	return !is_multicast_ether_addr(addr) && !is_zero_ether_addr(addr);
+}
+
+typedef void rx_handler_f(char *packet, unsigned int len);
+
+void eth_set_current(struct eth_device *eth);
+struct eth_device *eth_get_current(void);
+struct eth_device *eth_get_byname(char *name);
+void net_update_env(void);
+
+/**
+ * net_receive - Pass a received packet from an ethernet driver to the protocol stack
+ * @pkt: Pointer to the packet
+ * @len: length of the packet
+ *
+ * Return 0 if the packet is successfully handled. Can be ignored
+ */
+int net_receive(unsigned char *pkt, int len);
+
+struct net_connection {
+	struct ethernet *et;
+	struct iphdr *ip;
+	struct udphdr *udp;
+	struct icmphdr *icmp;
+	unsigned char *packet;
+	struct list_head list;
+	rx_handler_f *handler;
+	int proto;
+};
+
+static inline char *net_alloc_packet(void)
+{
+	return memalign(32, PKTSIZE);
+}
+
+struct net_connection *net_udp_new(IPaddr_t dest, uint16_t dport,
+		rx_handler_f *handler);
+
+struct net_connection *net_icmp_new(IPaddr_t dest, rx_handler_f *handler);
+
+void net_unregister(struct net_connection *con);
+
+static inline int net_udp_bind(struct net_connection *con, int sport)
+{
+	con->udp->uh_sport = ntohs(sport);
+	return 0;
+}
+
+static inline unsigned char *net_udp_get_payload(struct net_connection *con)
+{
+	return con->packet + sizeof(struct ethernet) + sizeof(struct iphdr) +
+		sizeof(struct udphdr);
+}
+
+int net_udp_send(struct net_connection *con, int len);
+int net_icmp_send(struct net_connection *con, int len);
+
 #endif /* __NET_H__ */