diff options
Diffstat (limited to 'net/fastboot_tcp.c')
| -rw-r--r-- | net/fastboot_tcp.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/net/fastboot_tcp.c b/net/fastboot_tcp.c new file mode 100644 index 00000000000..2eb52ea2567 --- /dev/null +++ b/net/fastboot_tcp.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: BSD-2-Clause +/* + * Copyright (C) 2023 The Android Open Source Project + */ + +#include <common.h> +#include <fastboot.h> +#include <net.h> +#include <net/fastboot_tcp.h> +#include <net/tcp.h> + +static char command[FASTBOOT_COMMAND_LEN] = {0}; +static char response[FASTBOOT_RESPONSE_LEN] = {0}; + +static const unsigned short handshake_length = 4; +static const uchar *handshake = "FB01"; + +static u16 curr_sport; +static u16 curr_dport; +static u32 curr_tcp_seq_num; +static u32 curr_tcp_ack_num; +static unsigned int curr_request_len; +static enum fastboot_tcp_state { + FASTBOOT_CLOSED, + FASTBOOT_CONNECTED, + FASTBOOT_DISCONNECTING +} state = FASTBOOT_CLOSED; + +static void fastboot_tcp_answer(u8 action, unsigned int len) +{ + const u32 response_seq_num = curr_tcp_ack_num; + const u32 response_ack_num = curr_tcp_seq_num + + (curr_request_len > 0 ? curr_request_len : 1); + + net_send_tcp_packet(len, htons(curr_sport), htons(curr_dport), + action, response_seq_num, response_ack_num); +} + +static void fastboot_tcp_reset(void) +{ + fastboot_tcp_answer(TCP_RST, 0); + state = FASTBOOT_CLOSED; +} + +static void fastboot_tcp_send_packet(u8 action, const uchar *data, unsigned int len) +{ + uchar *pkt = net_get_async_tx_pkt_buf(); + + memset(pkt, '\0', PKTSIZE); + pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2; + memcpy(pkt, data, len); + fastboot_tcp_answer(action, len); + memset(pkt, '\0', PKTSIZE); +} + +static void fastboot_tcp_send_message(const char *message, unsigned int len) +{ + __be64 len_be = __cpu_to_be64(len); + uchar *pkt = net_get_async_tx_pkt_buf(); + + memset(pkt, '\0', PKTSIZE); + pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2; + // Put first 8 bytes as a big endian message length + memcpy(pkt, &len_be, 8); + pkt += 8; + memcpy(pkt, message, len); + fastboot_tcp_answer(TCP_ACK | TCP_PUSH, len + 8); + memset(pkt, '\0', PKTSIZE); +} + +static void fastboot_tcp_handler_ipv4(uchar *pkt, u16 dport, + struct in_addr sip, u16 sport, + u32 tcp_seq_num, u32 tcp_ack_num, + u8 action, unsigned int len) +{ + int fastboot_command_id; + u64 command_size; + u8 tcp_fin = action & TCP_FIN; + u8 tcp_push = action & TCP_PUSH; + + curr_sport = sport; + curr_dport = dport; + curr_tcp_seq_num = tcp_seq_num; + curr_tcp_ack_num = tcp_ack_num; + curr_request_len = len; + + switch (state) { + case FASTBOOT_CLOSED: + if (tcp_push) { + if (len != handshake_length || + strlen(pkt) != handshake_length || + memcmp(pkt, handshake, handshake_length) != 0) { + fastboot_tcp_reset(); + break; + } + fastboot_tcp_send_packet(TCP_ACK | TCP_PUSH, + handshake, handshake_length); + state = FASTBOOT_CONNECTED; + } + break; + case FASTBOOT_CONNECTED: + if (tcp_fin) { + fastboot_tcp_answer(TCP_FIN | TCP_ACK, 0); + state = FASTBOOT_DISCONNECTING; + break; + } + if (tcp_push) { + // First 8 bytes is big endian message length + command_size = __be64_to_cpu(*(u64 *)pkt); + len -= 8; + pkt += 8; + + // Only single packet messages are supported ATM + if (strlen(pkt) != command_size) { + fastboot_tcp_reset(); + break; + } + strlcpy(command, pkt, len + 1); + fastboot_command_id = fastboot_handle_command(command, response); + fastboot_tcp_send_message(response, strlen(response)); + fastboot_handle_boot(fastboot_command_id, + strncmp("OKAY", response, 4) == 0); + } + break; + case FASTBOOT_DISCONNECTING: + if (tcp_push) + state = FASTBOOT_CLOSED; + break; + } + + memset(command, 0, FASTBOOT_COMMAND_LEN); + memset(response, 0, FASTBOOT_RESPONSE_LEN); + curr_sport = 0; + curr_dport = 0; + curr_tcp_seq_num = 0; + curr_tcp_ack_num = 0; + curr_request_len = 0; +} + +void fastboot_tcp_start_server(void) +{ + printf("Using %s device\n", eth_get_name()); + printf("Listening for fastboot command on tcp %pI4\n", &net_ip); + + tcp_set_tcp_handler(fastboot_tcp_handler_ipv4); +} |