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