net/fastboot.c

   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  */
  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  */
  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  */
 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  */
 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  */
 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
 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 }