1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (C) 2016 The Android Open Source Project
4  */
5 
6 #include <common.h>
7 #include <command.h>
8 #include <fastboot.h>
9 #include <net.h>
10 #include <net/fastboot.h>
11 
12 /* Fastboot port # defined in spec */
13 #define WELL_KNOWN_PORT 5554
14 
15 enum {
16 	FASTBOOT_ERROR = 0,
17 	FASTBOOT_QUERY = 1,
18 	FASTBOOT_INIT = 2,
19 	FASTBOOT_FASTBOOT = 3,
20 };
21 
22 struct __packed fastboot_header {
23 	uchar id;
24 	uchar flags;
25 	unsigned short seq;
26 };
27 
28 #define PACKET_SIZE 1024
29 #define DATA_SIZE (PACKET_SIZE - sizeof(struct fastboot_header))
30 
31 /* Sequence number sent for every packet */
32 static unsigned short sequence_number = 1;
33 static const unsigned short packet_size = PACKET_SIZE;
34 static const unsigned short udp_version = 1;
35 
36 /* Keep track of last packet for resubmission */
37 static uchar last_packet[PACKET_SIZE];
38 static unsigned int last_packet_len;
39 
40 static struct in_addr fastboot_remote_ip;
41 /* The UDP port at their end */
42 static int fastboot_remote_port;
43 /* The UDP port at our end */
44 static int fastboot_our_port;
45 
46 static void boot_downloaded_image(void);
47 
48 #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
49 /**
50  * fastboot_udp_send_info() - Send an INFO packet during long commands.
51  *
52  * @msg: String describing the reason for waiting
53  */
fastboot_udp_send_info(const char * msg)54 static void fastboot_udp_send_info(const char *msg)
55 {
56 	uchar *packet;
57 	uchar *packet_base;
58 	int len = 0;
59 	char response[FASTBOOT_RESPONSE_LEN] = {0};
60 
61 	struct fastboot_header response_header = {
62 		.id = FASTBOOT_FASTBOOT,
63 		.flags = 0,
64 		.seq = htons(sequence_number)
65 	};
66 	++sequence_number;
67 	packet = net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
68 	packet_base = packet;
69 
70 	/* Write headers */
71 	memcpy(packet, &response_header, sizeof(response_header));
72 	packet += sizeof(response_header);
73 	/* Write response */
74 	fastboot_response("INFO", response, "%s", msg);
75 	memcpy(packet, response, strlen(response));
76 	packet += strlen(response);
77 
78 	len = packet - packet_base;
79 
80 	/* Save packet for retransmitting */
81 	last_packet_len = len;
82 	memcpy(last_packet, packet_base, last_packet_len);
83 
84 	net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
85 			    fastboot_remote_port, fastboot_our_port, len);
86 }
87 
88 /**
89  * fastboot_timed_send_info() - Send INFO packet every 30 seconds
90  *
91  * @msg: String describing the reason for waiting
92  *
93  * Send an INFO packet during long commands based on timer. An INFO packet
94  * is sent if the time is 30 seconds after start. Else, noop.
95  */
fastboot_timed_send_info(const char * msg)96 static void fastboot_timed_send_info(const char *msg)
97 {
98 	static ulong start;
99 
100 	/* Initialize timer */
101 	if (start == 0)
102 		start = get_timer(0);
103 	ulong time = get_timer(start);
104 	/* Send INFO packet to host every 30 seconds */
105 	if (time >= 30000) {
106 		start = get_timer(0);
107 		fastboot_udp_send_info(msg);
108 	}
109 }
110 #endif
111 
112 /**
113  * fastboot_send() - Sends a packet in response to received fastboot packet
114  *
115  * @header: Header for response packet
116  * @fastboot_data: Pointer to received fastboot data
117  * @fastboot_data_len: Length of received fastboot data
118  * @retransmit: Nonzero if sending last sent packet
119  */
fastboot_send(struct fastboot_header header,char * fastboot_data,unsigned int fastboot_data_len,uchar retransmit)120 static void fastboot_send(struct fastboot_header header, char *fastboot_data,
121 			  unsigned int fastboot_data_len, uchar retransmit)
122 {
123 	uchar *packet;
124 	uchar *packet_base;
125 	int len = 0;
126 	const char *error_msg = "An error occurred.";
127 	short tmp;
128 	struct fastboot_header response_header = header;
129 	static char command[FASTBOOT_COMMAND_LEN];
130 	static int cmd = -1;
131 	static bool pending_command;
132 	char response[FASTBOOT_RESPONSE_LEN] = {0};
133 
134 	/*
135 	 * We will always be sending some sort of packet, so
136 	 * cobble together the packet headers now.
137 	 */
138 	packet = net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
139 	packet_base = packet;
140 
141 	/* Resend last packet */
142 	if (retransmit) {
143 		memcpy(packet, last_packet, last_packet_len);
144 		net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
145 				    fastboot_remote_port, fastboot_our_port,
146 				    last_packet_len);
147 		return;
148 	}
149 
150 	response_header.seq = htons(response_header.seq);
151 	memcpy(packet, &response_header, sizeof(response_header));
152 	packet += sizeof(response_header);
153 
154 	switch (header.id) {
155 	case FASTBOOT_QUERY:
156 		tmp = htons(sequence_number);
157 		memcpy(packet, &tmp, sizeof(tmp));
158 		packet += sizeof(tmp);
159 		break;
160 	case FASTBOOT_INIT:
161 		tmp = htons(udp_version);
162 		memcpy(packet, &tmp, sizeof(tmp));
163 		packet += sizeof(tmp);
164 		tmp = htons(packet_size);
165 		memcpy(packet, &tmp, sizeof(tmp));
166 		packet += sizeof(tmp);
167 		break;
168 	case FASTBOOT_ERROR:
169 		memcpy(packet, error_msg, strlen(error_msg));
170 		packet += strlen(error_msg);
171 		break;
172 	case FASTBOOT_FASTBOOT:
173 		if (cmd == FASTBOOT_COMMAND_DOWNLOAD) {
174 			if (!fastboot_data_len && !fastboot_data_remaining()) {
175 				fastboot_data_complete(response);
176 			} else {
177 				fastboot_data_download(fastboot_data,
178 						       fastboot_data_len,
179 						       response);
180 			}
181 		} else if (!pending_command) {
182 			strlcpy(command, fastboot_data,
183 				min((size_t)fastboot_data_len + 1,
184 				    sizeof(command)));
185 			pending_command = true;
186 		} else {
187 			cmd = fastboot_handle_command(command, response);
188 			pending_command = false;
189 		}
190 		/*
191 		 * Sent some INFO packets, need to update sequence number in
192 		 * header
193 		 */
194 		if (header.seq != sequence_number) {
195 			response_header.seq = htons(sequence_number);
196 			memcpy(packet_base, &response_header,
197 			       sizeof(response_header));
198 		}
199 		/* Write response to packet */
200 		memcpy(packet, response, strlen(response));
201 		packet += strlen(response);
202 		break;
203 	default:
204 		pr_err("ID %d not implemented.\n", header.id);
205 		return;
206 	}
207 
208 	len = packet - packet_base;
209 
210 	/* Save packet for retransmitting */
211 	last_packet_len = len;
212 	memcpy(last_packet, packet_base, last_packet_len);
213 
214 	net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
215 			    fastboot_remote_port, fastboot_our_port, len);
216 
217 	/* Continue boot process after sending response */
218 	if (!strncmp("OKAY", response, 4)) {
219 		switch (cmd) {
220 		case FASTBOOT_COMMAND_BOOT:
221 			boot_downloaded_image();
222 			break;
223 
224 		case FASTBOOT_COMMAND_CONTINUE:
225 			net_set_state(NETLOOP_SUCCESS);
226 			break;
227 
228 		case FASTBOOT_COMMAND_REBOOT:
229 		case FASTBOOT_COMMAND_REBOOT_BOOTLOADER:
230 		case FASTBOOT_COMMAND_REBOOT_FASTBOOTD:
231 		case FASTBOOT_COMMAND_REBOOT_RECOVERY:
232 			do_reset(NULL, 0, 0, NULL);
233 			break;
234 		}
235 	}
236 
237 	if (!strncmp("OKAY", response, 4) || !strncmp("FAIL", response, 4))
238 		cmd = -1;
239 }
240 
241 /**
242  * boot_downloaded_image() - Boots into downloaded image.
243  */
boot_downloaded_image(void)244 static void boot_downloaded_image(void)
245 {
246 	fastboot_boot();
247 	net_set_state(NETLOOP_SUCCESS);
248 }
249 
250 /**
251  * fastboot_handler() - Incoming UDP packet handler.
252  *
253  * @packet: Pointer to incoming UDP packet
254  * @dport: Destination UDP port
255  * @sip: Source IP address
256  * @sport: Source UDP port
257  * @len: Packet length
258  */
fastboot_handler(uchar * packet,unsigned int dport,struct in_addr sip,unsigned int sport,unsigned int len)259 static void fastboot_handler(uchar *packet, unsigned int dport,
260 			     struct in_addr sip, unsigned int sport,
261 			     unsigned int len)
262 {
263 	struct fastboot_header header;
264 	char fastboot_data[DATA_SIZE] = {0};
265 	unsigned int fastboot_data_len = 0;
266 
267 	if (dport != fastboot_our_port)
268 		return;
269 
270 	fastboot_remote_ip = sip;
271 	fastboot_remote_port = sport;
272 
273 	if (len < sizeof(struct fastboot_header) || len > PACKET_SIZE)
274 		return;
275 	memcpy(&header, packet, sizeof(header));
276 	header.flags = 0;
277 	header.seq = ntohs(header.seq);
278 	packet += sizeof(header);
279 	len -= sizeof(header);
280 
281 	switch (header.id) {
282 	case FASTBOOT_QUERY:
283 		fastboot_send(header, fastboot_data, 0, 0);
284 		break;
285 	case FASTBOOT_INIT:
286 	case FASTBOOT_FASTBOOT:
287 		fastboot_data_len = len;
288 		if (len > 0)
289 			memcpy(fastboot_data, packet, len);
290 		if (header.seq == sequence_number) {
291 			fastboot_send(header, fastboot_data,
292 				      fastboot_data_len, 0);
293 			sequence_number++;
294 		} else if (header.seq == sequence_number - 1) {
295 			/* Retransmit last sent packet */
296 			fastboot_send(header, fastboot_data,
297 				      fastboot_data_len, 1);
298 		}
299 		break;
300 	default:
301 		pr_err("ID %d not implemented.\n", header.id);
302 		header.id = FASTBOOT_ERROR;
303 		fastboot_send(header, fastboot_data, 0, 0);
304 		break;
305 	}
306 }
307 
fastboot_start_server(void)308 void fastboot_start_server(void)
309 {
310 	printf("Using %s device\n", eth_get_name());
311 	printf("Listening for fastboot command on %pI4\n", &net_ip);
312 
313 	fastboot_our_port = WELL_KNOWN_PORT;
314 
315 #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
316 	fastboot_set_progress_callback(fastboot_timed_send_info);
317 #endif
318 	net_set_udp_handler(fastboot_handler);
319 
320 	/* zero out server ether in case the server ip has changed */
321 	memset(net_server_ethaddr, 0, 6);
322 }
323