xref: /openbmc/u-boot/drivers/net/netconsole.c (revision 9c0e2f6e)
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 struct in_addr 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 				 struct in_addr 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, struct in_addr sip,
45 		       unsigned src, 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_handler(void)
52 {
53 	net_set_state(NETLOOP_SUCCESS);
54 }
55 
56 static int is_broadcast(struct in_addr ip)
57 {
58 	static struct in_addr netmask;
59 	static struct in_addr 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 = env_get_ip("netmask");
66 		our_ip = env_get_ip("ipaddr");
67 
68 		env_changed_id = env_id;
69 	}
70 
71 	return (ip.s_addr == ~0 || /* 255.255.255.255 (global bcast) */
72 		((netmask.s_addr & our_ip.s_addr) ==
73 		 (netmask.s_addr & ip.s_addr) && /* on the same net and */
74 		 (netmask.s_addr | ip.s_addr) == ~0)); /* bcast to our net */
75 }
76 
77 static int refresh_settings_from_env(void)
78 {
79 	const char *p;
80 	static int env_changed_id;
81 	int env_id = get_env_id();
82 
83 	/* update only when the environment has changed */
84 	if (env_changed_id != env_id) {
85 		if (env_get("ncip")) {
86 			nc_ip = env_get_ip("ncip");
87 			if (!nc_ip.s_addr)
88 				return -1;	/* ncip is 0.0.0.0 */
89 			p = strchr(env_get("ncip"), ':');
90 			if (p != NULL) {
91 				nc_out_port = simple_strtoul(p + 1, NULL, 10);
92 				nc_in_port = nc_out_port;
93 			}
94 		} else {
95 			nc_ip.s_addr = ~0; /* ncip is not set, so broadcast */
96 		}
97 
98 		p = env_get("ncoutport");
99 		if (p != NULL)
100 			nc_out_port = simple_strtoul(p, NULL, 10);
101 		p = env_get("ncinport");
102 		if (p != NULL)
103 			nc_in_port = simple_strtoul(p, NULL, 10);
104 
105 		if (is_broadcast(nc_ip))
106 			/* broadcast MAC address */
107 			memset(nc_ether, 0xff, sizeof(nc_ether));
108 		else
109 			/* force arp request */
110 			memset(nc_ether, 0, sizeof(nc_ether));
111 	}
112 	return 0;
113 }
114 
115 /**
116  * Called from net_loop in net/net.c before each packet
117  */
118 void nc_start(void)
119 {
120 	refresh_settings_from_env();
121 	if (!output_packet_len || memcmp(nc_ether, net_null_ethaddr, 6)) {
122 		/* going to check for input packet */
123 		net_set_udp_handler(nc_handler);
124 		net_set_timeout_handler(net_timeout, nc_timeout_handler);
125 	} else {
126 		/* send arp request */
127 		uchar *pkt;
128 		net_set_arp_handler(nc_wait_arp_handler);
129 		pkt = (uchar *)net_tx_packet + net_eth_hdr_size() +
130 			IP_UDP_HDR_SIZE;
131 		memcpy(pkt, output_packet, output_packet_len);
132 		net_send_udp_packet(nc_ether, nc_ip, nc_out_port, nc_in_port,
133 				    output_packet_len);
134 	}
135 }
136 
137 int nc_input_packet(uchar *pkt, struct in_addr src_ip, unsigned dest_port,
138 	unsigned src_port, unsigned len)
139 {
140 	int end, chunk;
141 
142 	if (dest_port != nc_in_port || !len)
143 		return 0; /* not for us */
144 
145 	if (src_ip.s_addr != nc_ip.s_addr && !is_broadcast(nc_ip))
146 		return 0; /* not from our client */
147 
148 	debug_cond(DEBUG_DEV_PKT, "input: \"%*.*s\"\n", len, len, pkt);
149 
150 	if (input_size == sizeof(input_buffer))
151 		return 1; /* no space */
152 	if (len > sizeof(input_buffer) - input_size)
153 		len = sizeof(input_buffer) - input_size;
154 
155 	end = input_offset + input_size;
156 	if (end >= sizeof(input_buffer))
157 		end -= sizeof(input_buffer);
158 
159 	chunk = len;
160 	/* Check if packet will wrap in input_buffer */
161 	if (end + len >= sizeof(input_buffer)) {
162 		chunk = sizeof(input_buffer) - end;
163 		/* Copy the second part of the pkt to start of input_buffer */
164 		memcpy(input_buffer, pkt + chunk, len - chunk);
165 	}
166 	/* Copy first (or only) part of pkt after end of current valid input*/
167 	memcpy(input_buffer + end, pkt, chunk);
168 
169 	input_size += len;
170 
171 	return 1;
172 }
173 
174 static void nc_send_packet(const char *buf, int len)
175 {
176 #ifdef CONFIG_DM_ETH
177 	struct udevice *eth;
178 #else
179 	struct eth_device *eth;
180 #endif
181 	int inited = 0;
182 	uchar *pkt;
183 	uchar *ether;
184 	struct in_addr ip;
185 
186 	debug_cond(DEBUG_DEV_PKT, "output: \"%*.*s\"\n", len, len, buf);
187 
188 	eth = eth_get_dev();
189 	if (eth == NULL)
190 		return;
191 
192 	if (!memcmp(nc_ether, net_null_ethaddr, 6)) {
193 		if (eth_is_active(eth))
194 			return;	/* inside net loop */
195 		output_packet = buf;
196 		output_packet_len = len;
197 		input_recursion = 1;
198 		net_loop(NETCONS); /* wait for arp reply and send packet */
199 		input_recursion = 0;
200 		output_packet_len = 0;
201 		return;
202 	}
203 
204 	if (!eth_is_active(eth)) {
205 		if (eth_is_on_demand_init()) {
206 			if (eth_init() < 0)
207 				return;
208 			eth_set_last_protocol(NETCONS);
209 		} else {
210 			eth_init_state_only();
211 		}
212 
213 		inited = 1;
214 	}
215 	pkt = (uchar *)net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
216 	memcpy(pkt, buf, len);
217 	ether = nc_ether;
218 	ip = nc_ip;
219 	net_send_udp_packet(ether, ip, nc_out_port, nc_in_port, len);
220 
221 	if (inited) {
222 		if (eth_is_on_demand_init())
223 			eth_halt();
224 		else
225 			eth_halt_state_only();
226 	}
227 }
228 
229 static int nc_stdio_start(struct stdio_dev *dev)
230 {
231 	int retval;
232 
233 	nc_out_port = 6666; /* default port */
234 	nc_in_port = nc_out_port;
235 
236 	retval = refresh_settings_from_env();
237 	if (retval != 0)
238 		return retval;
239 
240 	/*
241 	 * Initialize the static IP settings and buffer pointers
242 	 * incase we call net_send_udp_packet before net_loop
243 	 */
244 	net_init();
245 
246 	return 0;
247 }
248 
249 static void nc_stdio_putc(struct stdio_dev *dev, char c)
250 {
251 	if (output_recursion)
252 		return;
253 	output_recursion = 1;
254 
255 	nc_send_packet(&c, 1);
256 
257 	output_recursion = 0;
258 }
259 
260 static void nc_stdio_puts(struct stdio_dev *dev, const char *s)
261 {
262 	int len;
263 
264 	if (output_recursion)
265 		return;
266 	output_recursion = 1;
267 
268 	len = strlen(s);
269 	while (len) {
270 		int send_len = min(len, (int)sizeof(input_buffer));
271 		nc_send_packet(s, send_len);
272 		len -= send_len;
273 		s += send_len;
274 	}
275 
276 	output_recursion = 0;
277 }
278 
279 static int nc_stdio_getc(struct stdio_dev *dev)
280 {
281 	uchar c;
282 
283 	input_recursion = 1;
284 
285 	net_timeout = 0;	/* no timeout */
286 	while (!input_size)
287 		net_loop(NETCONS);
288 
289 	input_recursion = 0;
290 
291 	c = input_buffer[input_offset++];
292 
293 	if (input_offset >= sizeof(input_buffer))
294 		input_offset -= sizeof(input_buffer);
295 	input_size--;
296 
297 	return c;
298 }
299 
300 static int nc_stdio_tstc(struct stdio_dev *dev)
301 {
302 #ifdef CONFIG_DM_ETH
303 	struct udevice *eth;
304 #else
305 	struct eth_device *eth;
306 #endif
307 
308 	if (input_recursion)
309 		return 0;
310 
311 	if (input_size)
312 		return 1;
313 
314 	eth = eth_get_dev();
315 	if (eth_is_active(eth))
316 		return 0;	/* inside net loop */
317 
318 	input_recursion = 1;
319 
320 	net_timeout = 1;
321 	net_loop(NETCONS);	/* kind of poll */
322 
323 	input_recursion = 0;
324 
325 	return input_size != 0;
326 }
327 
328 int drv_nc_init(void)
329 {
330 	struct stdio_dev dev;
331 	int rc;
332 
333 	memset(&dev, 0, sizeof(dev));
334 
335 	strcpy(dev.name, "nc");
336 	dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
337 	dev.start = nc_stdio_start;
338 	dev.putc = nc_stdio_putc;
339 	dev.puts = nc_stdio_puts;
340 	dev.getc = nc_stdio_getc;
341 	dev.tstc = nc_stdio_tstc;
342 
343 	rc = stdio_register(&dev);
344 
345 	return (rc == 0) ? 1 : rc;
346 }
347