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 enum {
  13         FASTBOOT_ERROR = 0,
  14         FASTBOOT_QUERY = 1,
  15         FASTBOOT_INIT = 2,
  16         FASTBOOT_FASTBOOT = 3,
  17 };
  18
  19 struct __packed fastboot_header {
  20         uchar id;
  21         uchar flags;
  22         unsigned short seq;
  23 };
  24
  25 #define PACKET_SIZE 1024
  26 #define DATA_SIZE (PACKET_SIZE - sizeof(struct fastboot_header))
  27
  28 /* Sequence number sent for every packet */
  29 static unsigned short sequence_number = 1;
  30 static const unsigned short packet_size = PACKET_SIZE;
  31 static const unsigned short udp_version = 1;
  32
  33 /* Keep track of last packet for resubmission */
  34 static uchar last_packet[PACKET_SIZE];
  35 static unsigned int last_packet_len;
  36
  37 static struct in_addr fastboot_remote_ip;
  38 /* The UDP port at their end */
  39 static int fastboot_remote_port;
  40 /* The UDP port at our end */
  41 static int fastboot_our_port;
  42
  43 static void boot_downloaded_image(void);
  44
  45 #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
  46 /**
  47  * fastboot_udp_send_info() - Send an INFO packet during long commands.
  48  *
  49  * @msg: String describing the reason for waiting
  50  */
  51 static void fastboot_udp_send_info(const char *msg)
  52 {
  53         uchar *packet;
  54         uchar *packet_base;
  55         int len = 0;
  56         char response[FASTBOOT_RESPONSE_LEN] = {0};
  57
  58         struct fastboot_header response_header = {
  59                 .id = FASTBOOT_FASTBOOT,
  60                 .flags = 0,
  61                 .seq = htons(sequence_number)
  62         };
  63         ++sequence_number;
  64         packet = net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
  65         packet_base = packet;
  66
  67         /* Write headers */
  68         memcpy(packet, &response_header, sizeof(response_header));
  69         packet += sizeof(response_header);
  70         /* Write response */
  71         fastboot_response("INFO", response, "%s", msg);
  72         memcpy(packet, response, strlen(response));
  73         packet += strlen(response);
  74
  75         len = packet - packet_base;
  76
  77         /* Save packet for retransmitting */
  78         last_packet_len = len;
  79         memcpy(last_packet, packet_base, last_packet_len);
  80
  81         net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
  82                             fastboot_remote_port, fastboot_our_port, len);
  83 }
  84
  85 /**
  86  * fastboot_timed_send_info() - Send INFO packet every 30 seconds
  87  *
  88  * @msg: String describing the reason for waiting
  89  *
  90  * Send an INFO packet during long commands based on timer. An INFO packet
  91  * is sent if the time is 30 seconds after start. Else, noop.
  92  */
  93 static void fastboot_timed_send_info(const char *msg)
  94 {
  95         static ulong start;
  96
  97         /* Initialize timer */
  98         if (start == 0)
  99                 start = get_timer(0);
 100         ulong time = get_timer(start);
 101         /* Send INFO packet to host every 30 seconds */
 102         if (time >= 30000) {
 103                 start = get_timer(0);
 104                 fastboot_udp_send_info(msg);
 105         }
 106 }
 107 #endif
 108
 109 /**
 110  * fastboot_send() - Sends a packet in response to received fastboot packet
 111  *
 112  * @header: Header for response packet
 113  * @fastboot_data: Pointer to received fastboot data
 114  * @fastboot_data_len: Length of received fastboot data
 115  * @retransmit: Nonzero if sending last sent packet
 116  */
 117 static void fastboot_send(struct fastboot_header header, char *fastboot_data,
 118                           unsigned int fastboot_data_len, uchar retransmit)
 119 {
 120         uchar *packet;
 121         uchar *packet_base;
 122         int len = 0;
 123         const char *error_msg = "An error occurred.";
 124         short tmp;
 125         struct fastboot_header response_header = header;
 126         static char command[FASTBOOT_COMMAND_LEN];
 127         static int cmd = -1;
 128         static bool pending_command;
 129         char response[FASTBOOT_RESPONSE_LEN] = {0};
 130
 131         /*
 132          * We will always be sending some sort of packet, so
 133          * cobble together the packet headers now.
 134          */
 135         packet = net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE;
 136         packet_base = packet;
 137
 138         /* Resend last packet */
 139         if (retransmit) {
 140                 memcpy(packet, last_packet, last_packet_len);
 141                 net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
 142                                     fastboot_remote_port, fastboot_our_port,
 143                                     last_packet_len);
 144                 return;
 145         }
 146
 147         response_header.seq = htons(response_header.seq);
 148         memcpy(packet, &response_header, sizeof(response_header));
 149         packet += sizeof(response_header);
 150
 151         switch (header.id) {
 152         case FASTBOOT_QUERY:
 153                 tmp = htons(sequence_number);
 154                 memcpy(packet, &tmp, sizeof(tmp));
 155                 packet += sizeof(tmp);
 156                 break;
 157         case FASTBOOT_INIT:
 158                 tmp = htons(udp_version);
 159                 memcpy(packet, &tmp, sizeof(tmp));
 160                 packet += sizeof(tmp);
 161                 tmp = htons(packet_size);
 162                 memcpy(packet, &tmp, sizeof(tmp));
 163                 packet += sizeof(tmp);
 164                 break;
 165         case FASTBOOT_ERROR:
 166                 memcpy(packet, error_msg, strlen(error_msg));
 167                 packet += strlen(error_msg);
 168                 break;
 169         case FASTBOOT_FASTBOOT:
 170                 if (cmd == FASTBOOT_COMMAND_DOWNLOAD) {
 171                         if (!fastboot_data_len && !fastboot_data_remaining()) {
 172                                 fastboot_data_complete(response);
 173                         } else {
 174                                 fastboot_data_download(fastboot_data,
 175                                                        fastboot_data_len,
 176                                                        response);
 177                         }
 178                 } else if (!pending_command) {
 179                         strlcpy(command, fastboot_data,
 180                                 min((size_t)fastboot_data_len + 1,
 181                                     sizeof(command)));
 182                         pending_command = true;
 183                 } else {
 184                         cmd = fastboot_handle_command(command, response);
 185                         pending_command = false;
 186                 }
 187                 /*
 188                  * Sent some INFO packets, need to update sequence number in
 189                  * header
 190                  */
 191                 if (header.seq != sequence_number) {
 192                         response_header.seq = htons(sequence_number);
 193                         memcpy(packet_base, &response_header,
 194                                sizeof(response_header));
 195                 }
 196                 /* Write response to packet */
 197                 memcpy(packet, response, strlen(response));
 198                 packet += strlen(response);
 199                 break;
 200         default:
 201                 pr_err("ID %d not implemented.\n", header.id);
 202                 return;
 203         }
 204
 205         len = packet - packet_base;
 206
 207         /* Save packet for retransmitting */
 208         last_packet_len = len;
 209         memcpy(last_packet, packet_base, last_packet_len);
 210
 211         net_send_udp_packet(net_server_ethaddr, fastboot_remote_ip,
 212                             fastboot_remote_port, fastboot_our_port, len);
 213
 214         /* Continue boot process after sending response */
 215         if (!strncmp("OKAY", response, 4)) {
 216                 switch (cmd) {
 217                 case FASTBOOT_COMMAND_BOOT:
 218                         boot_downloaded_image();
 219                         break;
 220
 221                 case FASTBOOT_COMMAND_CONTINUE:
 222                         net_set_state(NETLOOP_SUCCESS);
 223                         break;
 224
 225                 case FASTBOOT_COMMAND_REBOOT:
 226                 case FASTBOOT_COMMAND_REBOOT_BOOTLOADER:
 227                 case FASTBOOT_COMMAND_REBOOT_FASTBOOTD:
 228                 case FASTBOOT_COMMAND_REBOOT_RECOVERY:
 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  */
 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  */
 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
 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 = CONFIG_UDP_FUNCTION_FASTBOOT_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 }