xref: /openbmc/u-boot/drivers/net/netconsole.c (revision 70ad375e)
1 /*
2  * (C) Copyright 2004
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <command.h>
10 #include <stdio_dev.h>
11 #include <net.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 #ifndef CONFIG_NETCONSOLE_BUFFER_SIZE
16 #define CONFIG_NETCONSOLE_BUFFER_SIZE 512
17 #endif
18 
19 static char input_buffer[CONFIG_NETCONSOLE_BUFFER_SIZE];
20 static int input_size; /* char count in input buffer */
21 static int input_offset; /* offset to valid chars in input buffer */
22 static int input_recursion;
23 static int output_recursion;
24 static int net_timeout;
25 static uchar nc_ether[6]; /* server enet address */
26 static IPaddr_t nc_ip; /* server ip */
27 static short nc_out_port; /* target output port */
28 static short nc_in_port; /* source input port */
29 static const char *output_packet; /* used by first send udp */
30 static int output_packet_len;
31 /*
32  * Start with a default last protocol.
33  * We are only interested in NETCONS or not.
34  */
35 enum proto_t net_loop_last_protocol = BOOTP;
36 
37 static void nc_wait_arp_handler(uchar *pkt, unsigned dest,
38 				 IPaddr_t sip, unsigned src,
39 				 unsigned len)
40 {
41 	net_set_state(NETLOOP_SUCCESS); /* got arp reply - quit net loop */
42 }
43 
44 static void nc_handler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
45 			unsigned len)
46 {
47 	if (input_size)
48 		net_set_state(NETLOOP_SUCCESS); /* got input - quit net loop */
49 }
50 
51 static void nc_timeout(void)
52 {
53 	net_set_state(NETLOOP_SUCCESS);
54 }
55 
56 static int is_broadcast(IPaddr_t ip)
57 {
58 	static IPaddr_t netmask;
59 	static IPaddr_t our_ip;
60 	static int env_changed_id;
61 	int env_id = get_env_id();
62 
63 	/* update only when the environment has changed */
64 	if (env_changed_id != env_id) {
65 		netmask = getenv_IPaddr("netmask");
66 		our_ip = getenv_IPaddr("ipaddr");
67 
68 		env_changed_id = env_id;
69 	}
70 
71 	return (ip == ~0 ||				/* 255.255.255.255 */
72 	    ((netmask & our_ip) == (netmask & ip) &&	/* on the same net */
73 	    (netmask | ip) == ~0));		/* broadcast to our net */
74 }
75 
76 static int refresh_settings_from_env(void)
77 {
78 	const char *p;
79 	static int env_changed_id;
80 	int env_id = get_env_id();
81 
82 	/* update only when the environment has changed */
83 	if (env_changed_id != env_id) {
84 		if (getenv("ncip")) {
85 			nc_ip = getenv_IPaddr("ncip");
86 			if (!nc_ip)
87 				return -1;	/* ncip is 0.0.0.0 */
88 			p = strchr(getenv("ncip"), ':');
89 			if (p != NULL) {
90 				nc_out_port = simple_strtoul(p + 1, NULL, 10);
91 				nc_in_port = nc_out_port;
92 			}
93 		} else
94 			nc_ip = ~0; /* ncip is not set, so broadcast */
95 
96 		p = getenv("ncoutport");
97 		if (p != NULL)
98 			nc_out_port = simple_strtoul(p, NULL, 10);
99 		p = getenv("ncinport");
100 		if (p != NULL)
101 			nc_in_port = simple_strtoul(p, NULL, 10);
102 
103 		if (is_broadcast(nc_ip))
104 			/* broadcast MAC address */
105 			memset(nc_ether, 0xff, sizeof(nc_ether));
106 		else
107 			/* force arp request */
108 			memset(nc_ether, 0, sizeof(nc_ether));
109 	}
110 	return 0;
111 }
112 
113 /**
114  * Called from NetLoop in net/net.c before each packet
115  */
116 void NcStart(void)
117 {
118 	refresh_settings_from_env();
119 	if (!output_packet_len || memcmp(nc_ether, NetEtherNullAddr, 6)) {
120 		/* going to check for input packet */
121 		net_set_udp_handler(nc_handler);
122 		NetSetTimeout(net_timeout, nc_timeout);
123 	} else {
124 		/* send arp request */
125 		uchar *pkt;
126 		net_set_arp_handler(nc_wait_arp_handler);
127 		pkt = (uchar *)NetTxPacket + NetEthHdrSize() + IP_UDP_HDR_SIZE;
128 		memcpy(pkt, output_packet, output_packet_len);
129 		NetSendUDPPacket(nc_ether, nc_ip, nc_out_port, nc_in_port,
130 			output_packet_len);
131 	}
132 }
133 
134 int nc_input_packet(uchar *pkt, IPaddr_t src_ip, unsigned dest_port,
135 	unsigned src_port, unsigned len)
136 {
137 	int end, chunk;
138 
139 	if (dest_port != nc_in_port || !len)
140 		return 0; /* not for us */
141 
142 	if (src_ip != nc_ip && !is_broadcast(nc_ip))
143 		return 0; /* not from our client */
144 
145 	debug_cond(DEBUG_DEV_PKT, "input: \"%*.*s\"\n", len, len, pkt);
146 
147 	if (input_size == sizeof(input_buffer))
148 		return 1; /* no space */
149 	if (len > sizeof(input_buffer) - input_size)
150 		len = sizeof(input_buffer) - input_size;
151 
152 	end = input_offset + input_size;
153 	if (end > sizeof(input_buffer))
154 		end -= sizeof(input_buffer);
155 
156 	chunk = len;
157 	if (end + len > sizeof(input_buffer)) {
158 		chunk = sizeof(input_buffer) - end;
159 		memcpy(input_buffer, pkt + chunk, len - chunk);
160 	}
161 	memcpy(input_buffer + end, pkt, chunk);
162 
163 	input_size += len;
164 
165 	return 1;
166 }
167 
168 static void nc_send_packet(const char *buf, int len)
169 {
170 	struct eth_device *eth;
171 	int inited = 0;
172 	uchar *pkt;
173 	uchar *ether;
174 	IPaddr_t ip;
175 
176 	debug_cond(DEBUG_DEV_PKT, "output: \"%*.*s\"\n", len, len, buf);
177 
178 	eth = eth_get_dev();
179 	if (eth == NULL)
180 		return;
181 
182 	if (!memcmp(nc_ether, NetEtherNullAddr, 6)) {
183 		if (eth->state == ETH_STATE_ACTIVE)
184 			return;	/* inside net loop */
185 		output_packet = buf;
186 		output_packet_len = len;
187 		input_recursion = 1;
188 		NetLoop(NETCONS); /* wait for arp reply and send packet */
189 		input_recursion = 0;
190 		output_packet_len = 0;
191 		return;
192 	}
193 
194 	if (eth->state != ETH_STATE_ACTIVE) {
195 		if (eth_is_on_demand_init()) {
196 			if (eth_init(gd->bd) < 0)
197 				return;
198 			eth_set_last_protocol(NETCONS);
199 		} else
200 			eth_init_state_only(gd->bd);
201 
202 		inited = 1;
203 	}
204 	pkt = (uchar *)NetTxPacket + NetEthHdrSize() + IP_UDP_HDR_SIZE;
205 	memcpy(pkt, buf, len);
206 	ether = nc_ether;
207 	ip = nc_ip;
208 	NetSendUDPPacket(ether, ip, nc_out_port, nc_in_port, len);
209 
210 	if (inited) {
211 		if (eth_is_on_demand_init())
212 			eth_halt();
213 		else
214 			eth_halt_state_only();
215 	}
216 }
217 
218 static int nc_start(void)
219 {
220 	int retval;
221 
222 	nc_out_port = 6666; /* default port */
223 	nc_in_port = nc_out_port;
224 
225 	retval = refresh_settings_from_env();
226 	if (retval != 0)
227 		return retval;
228 
229 	/*
230 	 * Initialize the static IP settings and buffer pointers
231 	 * incase we call NetSendUDPPacket before NetLoop
232 	 */
233 	net_init();
234 
235 	return 0;
236 }
237 
238 static void nc_putc(char c)
239 {
240 	if (output_recursion)
241 		return;
242 	output_recursion = 1;
243 
244 	nc_send_packet(&c, 1);
245 
246 	output_recursion = 0;
247 }
248 
249 static void nc_puts(const char *s)
250 {
251 	int len;
252 
253 	if (output_recursion)
254 		return;
255 	output_recursion = 1;
256 
257 	len = strlen(s);
258 	while (len) {
259 		int send_len = min(len, sizeof(input_buffer));
260 		nc_send_packet(s, send_len);
261 		len -= send_len;
262 		s += send_len;
263 	}
264 
265 	output_recursion = 0;
266 }
267 
268 static int nc_getc(void)
269 {
270 	uchar c;
271 
272 	input_recursion = 1;
273 
274 	net_timeout = 0;	/* no timeout */
275 	while (!input_size)
276 		NetLoop(NETCONS);
277 
278 	input_recursion = 0;
279 
280 	c = input_buffer[input_offset++];
281 
282 	if (input_offset >= sizeof(input_buffer))
283 		input_offset -= sizeof(input_buffer);
284 	input_size--;
285 
286 	return c;
287 }
288 
289 static int nc_tstc(void)
290 {
291 	struct eth_device *eth;
292 
293 	if (input_recursion)
294 		return 0;
295 
296 	if (input_size)
297 		return 1;
298 
299 	eth = eth_get_dev();
300 	if (eth && eth->state == ETH_STATE_ACTIVE)
301 		return 0;	/* inside net loop */
302 
303 	input_recursion = 1;
304 
305 	net_timeout = 1;
306 	NetLoop(NETCONS);	/* kind of poll */
307 
308 	input_recursion = 0;
309 
310 	return input_size != 0;
311 }
312 
313 int drv_nc_init(void)
314 {
315 	struct stdio_dev dev;
316 	int rc;
317 
318 	memset(&dev, 0, sizeof(dev));
319 
320 	strcpy(dev.name, "nc");
321 	dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT | DEV_FLAGS_SYSTEM;
322 	dev.start = nc_start;
323 	dev.putc = nc_putc;
324 	dev.puts = nc_puts;
325 	dev.getc = nc_getc;
326 	dev.tstc = nc_tstc;
327 
328 	rc = stdio_register(&dev);
329 
330 	return (rc == 0) ? 1 : rc;
331 }
332