1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2004
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 #include <common.h>
8 #include <command.h>
9 #include <env.h>
10 #include <log.h>
11 #include <stdio_dev.h>
12 #include <net.h>
13 
14 #ifndef CFG_NETCONSOLE_BUFFER_SIZE
15 #define CFG_NETCONSOLE_BUFFER_SIZE 512
16 #endif
17 
18 static char input_buffer[CFG_NETCONSOLE_BUFFER_SIZE];
19 static int input_size; /* char count in input buffer */
20 static int input_offset; /* offset to valid chars in input buffer */
21 static int input_recursion;
22 static int output_recursion;
23 static int net_timeout;
24 static uchar nc_ether[6]; /* server enet address */
25 static struct in_addr nc_ip; /* server ip */
26 static short nc_out_port; /* target output port */
27 static short nc_in_port; /* source input port */
28 static const char *output_packet; /* used by first send udp */
29 static int output_packet_len;
30 /*
31  * Start with a default last protocol.
32  * We are only interested in NETCONS or not.
33  */
34 enum proto_t net_loop_last_protocol = BOOTP;
35 
nc_wait_arp_handler(uchar * pkt,unsigned dest,struct in_addr sip,unsigned src,unsigned len)36 static void nc_wait_arp_handler(uchar *pkt, unsigned dest,
37 				 struct in_addr sip, unsigned src,
38 				 unsigned len)
39 {
40 	net_set_state(NETLOOP_SUCCESS); /* got arp reply - quit net loop */
41 }
42 
nc_handler(uchar * pkt,unsigned dest,struct in_addr sip,unsigned src,unsigned len)43 static void nc_handler(uchar *pkt, unsigned dest, struct in_addr sip,
44 		       unsigned src, unsigned len)
45 {
46 	if (input_size)
47 		net_set_state(NETLOOP_SUCCESS); /* got input - quit net loop */
48 }
49 
nc_timeout_handler(void)50 static void nc_timeout_handler(void)
51 {
52 	net_set_state(NETLOOP_SUCCESS);
53 }
54 
is_broadcast(struct in_addr ip)55 static int is_broadcast(struct in_addr ip)
56 {
57 	static struct in_addr netmask;
58 	static struct in_addr our_ip;
59 	static int env_changed_id;
60 	int env_id = env_get_id();
61 
62 	/* update only when the environment has changed */
63 	if (env_changed_id != env_id) {
64 		netmask = env_get_ip("netmask");
65 		our_ip = env_get_ip("ipaddr");
66 
67 		env_changed_id = env_id;
68 	}
69 
70 	return (ip.s_addr == ~0 || /* 255.255.255.255 (global bcast) */
71 		((netmask.s_addr & our_ip.s_addr) ==
72 		 (netmask.s_addr & ip.s_addr) && /* on the same net and */
73 		 (netmask.s_addr | ip.s_addr) == ~0)); /* bcast to our net */
74 }
75 
refresh_settings_from_env(void)76 static int refresh_settings_from_env(void)
77 {
78 	const char *p;
79 	static int env_changed_id;
80 	int env_id = env_get_id();
81 
82 	/* update only when the environment has changed */
83 	if (env_changed_id != env_id) {
84 		if (env_get("ncip")) {
85 			nc_ip = env_get_ip("ncip");
86 			if (!nc_ip.s_addr)
87 				return -1;	/* ncip is 0.0.0.0 */
88 			p = strchr(env_get("ncip"), ':');
89 			if (p != NULL) {
90 				nc_out_port = dectoul(p + 1, NULL);
91 				nc_in_port = nc_out_port;
92 			}
93 		} else {
94 			nc_ip.s_addr = ~0; /* ncip is not set, so broadcast */
95 		}
96 
97 		p = env_get("ncoutport");
98 		if (p != NULL)
99 			nc_out_port = dectoul(p, NULL);
100 		p = env_get("ncinport");
101 		if (p != NULL)
102 			nc_in_port = dectoul(p, NULL);
103 
104 		if (is_broadcast(nc_ip))
105 			/* broadcast MAC address */
106 			memset(nc_ether, 0xff, sizeof(nc_ether));
107 		else
108 			/* force arp request */
109 			memset(nc_ether, 0, sizeof(nc_ether));
110 	}
111 	return 0;
112 }
113 
114 /**
115  * Called from net_loop in net/net.c before each packet
116  */
nc_start(void)117 void nc_start(void)
118 {
119 	refresh_settings_from_env();
120 	if (!output_packet_len || memcmp(nc_ether, net_null_ethaddr, 6)) {
121 		/* going to check for input packet */
122 		net_set_udp_handler(nc_handler);
123 		net_set_timeout_handler(net_timeout, nc_timeout_handler);
124 	} else {
125 		/* send arp request */
126 		uchar *pkt;
127 		net_set_arp_handler(nc_wait_arp_handler);
128 		pkt = (uchar *)net_tx_packet + net_eth_hdr_size() +
129 			IP_UDP_HDR_SIZE;
130 		memcpy(pkt, output_packet, output_packet_len);
131 		net_send_udp_packet(nc_ether, nc_ip, nc_out_port, nc_in_port,
132 				    output_packet_len);
133 	}
134 }
135 
nc_input_packet(uchar * pkt,struct in_addr src_ip,unsigned dest_port,unsigned src_port,unsigned len)136 int nc_input_packet(uchar *pkt, struct in_addr src_ip, unsigned dest_port,
137 	unsigned src_port, unsigned len)
138 {
139 	int end, chunk;
140 
141 	if (dest_port != nc_in_port || !len)
142 		return 0; /* not for us */
143 
144 	if (src_ip.s_addr != nc_ip.s_addr && !is_broadcast(nc_ip))
145 		return 0; /* not from our client */
146 
147 	debug_cond(DEBUG_DEV_PKT, "input: \"%*.*s\"\n", len, len, pkt);
148 
149 	if (input_size == sizeof(input_buffer))
150 		return 1; /* no space */
151 	if (len > sizeof(input_buffer) - input_size)
152 		len = sizeof(input_buffer) - input_size;
153 
154 	end = input_offset + input_size;
155 	if (end >= sizeof(input_buffer))
156 		end -= sizeof(input_buffer);
157 
158 	chunk = len;
159 	/* Check if packet will wrap in input_buffer */
160 	if (end + len >= sizeof(input_buffer)) {
161 		chunk = sizeof(input_buffer) - end;
162 		/* Copy the second part of the pkt to start of input_buffer */
163 		memcpy(input_buffer, pkt + chunk, len - chunk);
164 	}
165 	/* Copy first (or only) part of pkt after end of current valid input*/
166 	memcpy(input_buffer + end, pkt, chunk);
167 
168 	input_size += len;
169 
170 	return 1;
171 }
172 
nc_send_packet(const char * buf,int len)173 static void nc_send_packet(const char *buf, int len)
174 {
175 	struct udevice *eth;
176 	int inited = 0;
177 	uchar *pkt;
178 	uchar *ether;
179 	struct in_addr ip;
180 
181 	debug_cond(DEBUG_DEV_PKT, "output: \"%*.*s\"\n", len, len, buf);
182 
183 	eth = eth_get_dev();
184 	if (eth == NULL)
185 		return;
186 
187 	if (!memcmp(nc_ether, net_null_ethaddr, 6)) {
188 		if (eth_is_active(eth))
189 			return;	/* inside net loop */
190 		output_packet = buf;
191 		output_packet_len = len;
192 		input_recursion = 1;
193 		net_loop(NETCONS); /* wait for arp reply and send packet */
194 		input_recursion = 0;
195 		output_packet_len = 0;
196 		return;
197 	}
198 
199 	if (!eth_is_active(eth)) {
200 		if (eth_is_on_demand_init()) {
201 			if (eth_init() < 0)
202 				return;
203 			eth_set_last_protocol(NETCONS);
204 		} else {
205 			eth_init_state_only();
206 		}
207 
208 		inited = 1;
209 	}
210 	pkt = (uchar *)net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
211 	memcpy(pkt, buf, len);
212 	ether = nc_ether;
213 	ip = nc_ip;
214 	net_send_udp_packet(ether, ip, nc_out_port, nc_in_port, len);
215 
216 	if (inited) {
217 		if (eth_is_on_demand_init())
218 			eth_halt();
219 		else
220 			eth_halt_state_only();
221 	}
222 }
223 
nc_stdio_start(struct stdio_dev * dev)224 static int nc_stdio_start(struct stdio_dev *dev)
225 {
226 	int retval;
227 
228 	nc_out_port = 6666; /* default port */
229 	nc_in_port = nc_out_port;
230 
231 	retval = refresh_settings_from_env();
232 	if (retval != 0)
233 		return retval;
234 
235 	/*
236 	 * Initialize the static IP settings and buffer pointers
237 	 * incase we call net_send_udp_packet before net_loop
238 	 */
239 	net_init();
240 
241 	return 0;
242 }
243 
nc_stdio_putc(struct stdio_dev * dev,char c)244 static void nc_stdio_putc(struct stdio_dev *dev, char c)
245 {
246 	if (output_recursion)
247 		return;
248 	output_recursion = 1;
249 
250 	nc_send_packet(&c, 1);
251 
252 	output_recursion = 0;
253 }
254 
nc_stdio_puts(struct stdio_dev * dev,const char * s)255 static void nc_stdio_puts(struct stdio_dev *dev, const char *s)
256 {
257 	int len;
258 
259 	if (output_recursion)
260 		return;
261 	output_recursion = 1;
262 
263 	len = strlen(s);
264 	while (len) {
265 		int send_len = min(len, (int)sizeof(input_buffer));
266 		nc_send_packet(s, send_len);
267 		len -= send_len;
268 		s += send_len;
269 	}
270 
271 	output_recursion = 0;
272 }
273 
nc_stdio_getc(struct stdio_dev * dev)274 static int nc_stdio_getc(struct stdio_dev *dev)
275 {
276 	uchar c;
277 
278 	input_recursion = 1;
279 
280 	net_timeout = 0;	/* no timeout */
281 	while (!input_size)
282 		net_loop(NETCONS);
283 
284 	input_recursion = 0;
285 
286 	c = input_buffer[input_offset++];
287 
288 	if (input_offset >= sizeof(input_buffer))
289 		input_offset -= sizeof(input_buffer);
290 	input_size--;
291 
292 	return c;
293 }
294 
nc_stdio_tstc(struct stdio_dev * dev)295 static int nc_stdio_tstc(struct stdio_dev *dev)
296 {
297 	struct udevice *eth;
298 
299 	if (input_recursion)
300 		return 0;
301 
302 	if (input_size)
303 		return 1;
304 
305 	eth = eth_get_dev();
306 	if (eth_is_active(eth))
307 		return 0;	/* inside net loop */
308 
309 	input_recursion = 1;
310 
311 	net_timeout = 1;
312 	net_loop(NETCONS);	/* kind of poll */
313 
314 	input_recursion = 0;
315 
316 	return input_size != 0;
317 }
318 
drv_nc_init(void)319 int drv_nc_init(void)
320 {
321 	struct stdio_dev dev;
322 	int rc;
323 
324 	memset(&dev, 0, sizeof(dev));
325 
326 	strcpy(dev.name, "nc");
327 	dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
328 	dev.start = nc_stdio_start;
329 	dev.putc = nc_stdio_putc;
330 	dev.puts = nc_stdio_puts;
331 	dev.getc = nc_stdio_getc;
332 	dev.tstc = nc_stdio_tstc;
333 
334 	rc = stdio_register(&dev);
335 
336 	return (rc == 0) ? 1 : rc;
337 }
338