xref: /openbmc/u-boot/drivers/net/netconsole.c (revision 87a62bce)
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 <stdio_dev.h>
10 #include <net.h>
11 
12 #ifndef CONFIG_NETCONSOLE_BUFFER_SIZE
13 #define CONFIG_NETCONSOLE_BUFFER_SIZE 512
14 #endif
15 
16 static char input_buffer[CONFIG_NETCONSOLE_BUFFER_SIZE];
17 static int input_size; /* char count in input buffer */
18 static int input_offset; /* offset to valid chars in input buffer */
19 static int input_recursion;
20 static int output_recursion;
21 static int net_timeout;
22 static uchar nc_ether[6]; /* server enet address */
23 static struct in_addr nc_ip; /* server ip */
24 static short nc_out_port; /* target output port */
25 static short nc_in_port; /* source input port */
26 static const char *output_packet; /* used by first send udp */
27 static int output_packet_len;
28 /*
29  * Start with a default last protocol.
30  * We are only interested in NETCONS or not.
31  */
32 enum proto_t net_loop_last_protocol = BOOTP;
33 
34 static void nc_wait_arp_handler(uchar *pkt, unsigned dest,
35 				 struct in_addr sip, unsigned src,
36 				 unsigned len)
37 {
38 	net_set_state(NETLOOP_SUCCESS); /* got arp reply - quit net loop */
39 }
40 
41 static void nc_handler(uchar *pkt, unsigned dest, struct in_addr sip,
42 		       unsigned src, unsigned len)
43 {
44 	if (input_size)
45 		net_set_state(NETLOOP_SUCCESS); /* got input - quit net loop */
46 }
47 
48 static void nc_timeout_handler(void)
49 {
50 	net_set_state(NETLOOP_SUCCESS);
51 }
52 
53 static int is_broadcast(struct in_addr ip)
54 {
55 	static struct in_addr netmask;
56 	static struct in_addr our_ip;
57 	static int env_changed_id;
58 	int env_id = get_env_id();
59 
60 	/* update only when the environment has changed */
61 	if (env_changed_id != env_id) {
62 		netmask = env_get_ip("netmask");
63 		our_ip = env_get_ip("ipaddr");
64 
65 		env_changed_id = env_id;
66 	}
67 
68 	return (ip.s_addr == ~0 || /* 255.255.255.255 (global bcast) */
69 		((netmask.s_addr & our_ip.s_addr) ==
70 		 (netmask.s_addr & ip.s_addr) && /* on the same net and */
71 		 (netmask.s_addr | ip.s_addr) == ~0)); /* bcast to our net */
72 }
73 
74 static int refresh_settings_from_env(void)
75 {
76 	const char *p;
77 	static int env_changed_id;
78 	int env_id = get_env_id();
79 
80 	/* update only when the environment has changed */
81 	if (env_changed_id != env_id) {
82 		if (env_get("ncip")) {
83 			nc_ip = env_get_ip("ncip");
84 			if (!nc_ip.s_addr)
85 				return -1;	/* ncip is 0.0.0.0 */
86 			p = strchr(env_get("ncip"), ':');
87 			if (p != NULL) {
88 				nc_out_port = simple_strtoul(p + 1, NULL, 10);
89 				nc_in_port = nc_out_port;
90 			}
91 		} else {
92 			nc_ip.s_addr = ~0; /* ncip is not set, so broadcast */
93 		}
94 
95 		p = env_get("ncoutport");
96 		if (p != NULL)
97 			nc_out_port = simple_strtoul(p, NULL, 10);
98 		p = env_get("ncinport");
99 		if (p != NULL)
100 			nc_in_port = simple_strtoul(p, NULL, 10);
101 
102 		if (is_broadcast(nc_ip))
103 			/* broadcast MAC address */
104 			memset(nc_ether, 0xff, sizeof(nc_ether));
105 		else
106 			/* force arp request */
107 			memset(nc_ether, 0, sizeof(nc_ether));
108 	}
109 	return 0;
110 }
111 
112 /**
113  * Called from net_loop in net/net.c before each packet
114  */
115 void nc_start(void)
116 {
117 	refresh_settings_from_env();
118 	if (!output_packet_len || memcmp(nc_ether, net_null_ethaddr, 6)) {
119 		/* going to check for input packet */
120 		net_set_udp_handler(nc_handler);
121 		net_set_timeout_handler(net_timeout, nc_timeout_handler);
122 	} else {
123 		/* send arp request */
124 		uchar *pkt;
125 		net_set_arp_handler(nc_wait_arp_handler);
126 		pkt = (uchar *)net_tx_packet + net_eth_hdr_size() +
127 			IP_UDP_HDR_SIZE;
128 		memcpy(pkt, output_packet, output_packet_len);
129 		net_send_udp_packet(nc_ether, nc_ip, nc_out_port, nc_in_port,
130 				    output_packet_len);
131 	}
132 }
133 
134 int nc_input_packet(uchar *pkt, struct in_addr 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.s_addr != nc_ip.s_addr && !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 	/* Check if packet will wrap in input_buffer */
158 	if (end + len >= sizeof(input_buffer)) {
159 		chunk = sizeof(input_buffer) - end;
160 		/* Copy the second part of the pkt to start of input_buffer */
161 		memcpy(input_buffer, pkt + chunk, len - chunk);
162 	}
163 	/* Copy first (or only) part of pkt after end of current valid input*/
164 	memcpy(input_buffer + end, pkt, chunk);
165 
166 	input_size += len;
167 
168 	return 1;
169 }
170 
171 static void nc_send_packet(const char *buf, int len)
172 {
173 #ifdef CONFIG_DM_ETH
174 	struct udevice *eth;
175 #else
176 	struct eth_device *eth;
177 #endif
178 	int inited = 0;
179 	uchar *pkt;
180 	uchar *ether;
181 	struct in_addr ip;
182 
183 	debug_cond(DEBUG_DEV_PKT, "output: \"%*.*s\"\n", len, len, buf);
184 
185 	eth = eth_get_dev();
186 	if (eth == NULL)
187 		return;
188 
189 	if (!memcmp(nc_ether, net_null_ethaddr, 6)) {
190 		if (eth_is_active(eth))
191 			return;	/* inside net loop */
192 		output_packet = buf;
193 		output_packet_len = len;
194 		input_recursion = 1;
195 		net_loop(NETCONS); /* wait for arp reply and send packet */
196 		input_recursion = 0;
197 		output_packet_len = 0;
198 		return;
199 	}
200 
201 	if (!eth_is_active(eth)) {
202 		if (eth_is_on_demand_init()) {
203 			if (eth_init() < 0)
204 				return;
205 			eth_set_last_protocol(NETCONS);
206 		} else {
207 			eth_init_state_only();
208 		}
209 
210 		inited = 1;
211 	}
212 	pkt = (uchar *)net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
213 	memcpy(pkt, buf, len);
214 	ether = nc_ether;
215 	ip = nc_ip;
216 	net_send_udp_packet(ether, ip, nc_out_port, nc_in_port, len);
217 
218 	if (inited) {
219 		if (eth_is_on_demand_init())
220 			eth_halt();
221 		else
222 			eth_halt_state_only();
223 	}
224 }
225 
226 static int nc_stdio_start(struct stdio_dev *dev)
227 {
228 	int retval;
229 
230 	nc_out_port = 6666; /* default port */
231 	nc_in_port = nc_out_port;
232 
233 	retval = refresh_settings_from_env();
234 	if (retval != 0)
235 		return retval;
236 
237 	/*
238 	 * Initialize the static IP settings and buffer pointers
239 	 * incase we call net_send_udp_packet before net_loop
240 	 */
241 	net_init();
242 
243 	return 0;
244 }
245 
246 static void nc_stdio_putc(struct stdio_dev *dev, char c)
247 {
248 	if (output_recursion)
249 		return;
250 	output_recursion = 1;
251 
252 	nc_send_packet(&c, 1);
253 
254 	output_recursion = 0;
255 }
256 
257 static void nc_stdio_puts(struct stdio_dev *dev, const char *s)
258 {
259 	int len;
260 
261 	if (output_recursion)
262 		return;
263 	output_recursion = 1;
264 
265 	len = strlen(s);
266 	while (len) {
267 		int send_len = min(len, (int)sizeof(input_buffer));
268 		nc_send_packet(s, send_len);
269 		len -= send_len;
270 		s += send_len;
271 	}
272 
273 	output_recursion = 0;
274 }
275 
276 static int nc_stdio_getc(struct stdio_dev *dev)
277 {
278 	uchar c;
279 
280 	input_recursion = 1;
281 
282 	net_timeout = 0;	/* no timeout */
283 	while (!input_size)
284 		net_loop(NETCONS);
285 
286 	input_recursion = 0;
287 
288 	c = input_buffer[input_offset++];
289 
290 	if (input_offset >= sizeof(input_buffer))
291 		input_offset -= sizeof(input_buffer);
292 	input_size--;
293 
294 	return c;
295 }
296 
297 static int nc_stdio_tstc(struct stdio_dev *dev)
298 {
299 #ifdef CONFIG_DM_ETH
300 	struct udevice *eth;
301 #else
302 	struct eth_device *eth;
303 #endif
304 
305 	if (input_recursion)
306 		return 0;
307 
308 	if (input_size)
309 		return 1;
310 
311 	eth = eth_get_dev();
312 	if (eth_is_active(eth))
313 		return 0;	/* inside net loop */
314 
315 	input_recursion = 1;
316 
317 	net_timeout = 1;
318 	net_loop(NETCONS);	/* kind of poll */
319 
320 	input_recursion = 0;
321 
322 	return input_size != 0;
323 }
324 
325 int drv_nc_init(void)
326 {
327 	struct stdio_dev dev;
328 	int rc;
329 
330 	memset(&dev, 0, sizeof(dev));
331 
332 	strcpy(dev.name, "nc");
333 	dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
334 	dev.start = nc_stdio_start;
335 	dev.putc = nc_stdio_putc;
336 	dev.puts = nc_stdio_puts;
337 	dev.getc = nc_stdio_getc;
338 	dev.tstc = nc_stdio_tstc;
339 
340 	rc = stdio_register(&dev);
341 
342 	return (rc == 0) ? 1 : rc;
343 }
344