1 // SPDX-License-Identifier: BSD-2-Clause
3 * Copyright (C) 2023 The Android Open Source Project
9 #include <net/fastboot_tcp.h>
12 static char command[FASTBOOT_COMMAND_LEN] = {0};
13 static char response[FASTBOOT_RESPONSE_LEN] = {0};
15 static const unsigned short handshake_length = 4;
16 static const uchar *handshake = "FB01";
18 static u16 curr_sport;
19 static u16 curr_dport;
20 static u32 curr_tcp_seq_num;
21 static u32 curr_tcp_ack_num;
22 static unsigned int curr_request_len;
23 static enum fastboot_tcp_state {
26 FASTBOOT_DISCONNECTING
27 } state = FASTBOOT_CLOSED;
29 static void fastboot_tcp_answer(u8 action, unsigned int len)
31 const u32 response_seq_num = curr_tcp_ack_num;
32 const u32 response_ack_num = curr_tcp_seq_num +
33 (curr_request_len > 0 ? curr_request_len : 1);
35 net_send_tcp_packet(len, htons(curr_sport), htons(curr_dport),
36 action, response_seq_num, response_ack_num);
39 static void fastboot_tcp_reset(void)
41 fastboot_tcp_answer(TCP_RST, 0);
42 state = FASTBOOT_CLOSED;
45 static void fastboot_tcp_send_packet(u8 action, const uchar *data, unsigned int len)
47 uchar *pkt = net_get_async_tx_pkt_buf();
49 memset(pkt, '\0', PKTSIZE);
50 pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2;
51 memcpy(pkt, data, len);
52 fastboot_tcp_answer(action, len);
53 memset(pkt, '\0', PKTSIZE);
56 static void fastboot_tcp_send_message(const char *message, unsigned int len)
58 __be64 len_be = __cpu_to_be64(len);
59 uchar *pkt = net_get_async_tx_pkt_buf();
61 memset(pkt, '\0', PKTSIZE);
62 pkt += net_eth_hdr_size() + IP_TCP_HDR_SIZE + TCP_TSOPT_SIZE + 2;
63 // Put first 8 bytes as a big endian message length
64 memcpy(pkt, &len_be, 8);
66 memcpy(pkt, message, len);
67 fastboot_tcp_answer(TCP_ACK | TCP_PUSH, len + 8);
68 memset(pkt, '\0', PKTSIZE);
71 static void fastboot_tcp_handler_ipv4(uchar *pkt, u16 dport,
72 struct in_addr sip, u16 sport,
73 u32 tcp_seq_num, u32 tcp_ack_num,
74 u8 action, unsigned int len)
76 int fastboot_command_id;
78 u8 tcp_fin = action & TCP_FIN;
79 u8 tcp_push = action & TCP_PUSH;
83 curr_tcp_seq_num = tcp_seq_num;
84 curr_tcp_ack_num = tcp_ack_num;
85 curr_request_len = len;
90 if (len != handshake_length ||
91 strlen(pkt) != handshake_length ||
92 memcmp(pkt, handshake, handshake_length) != 0) {
96 fastboot_tcp_send_packet(TCP_ACK | TCP_PUSH,
97 handshake, handshake_length);
98 state = FASTBOOT_CONNECTED;
101 case FASTBOOT_CONNECTED:
103 fastboot_tcp_answer(TCP_FIN | TCP_ACK, 0);
104 state = FASTBOOT_DISCONNECTING;
108 // First 8 bytes is big endian message length
109 command_size = __be64_to_cpu(*(u64 *)pkt);
113 // Only single packet messages are supported ATM
114 if (strlen(pkt) != command_size) {
115 fastboot_tcp_reset();
118 strlcpy(command, pkt, len + 1);
119 fastboot_command_id = fastboot_handle_command(command, response);
120 fastboot_tcp_send_message(response, strlen(response));
121 fastboot_handle_boot(fastboot_command_id,
122 strncmp("OKAY", response, 4) == 0);
125 case FASTBOOT_DISCONNECTING:
127 state = FASTBOOT_CLOSED;
131 memset(command, 0, FASTBOOT_COMMAND_LEN);
132 memset(response, 0, FASTBOOT_RESPONSE_LEN);
135 curr_tcp_seq_num = 0;
136 curr_tcp_ack_num = 0;
137 curr_request_len = 0;
140 void fastboot_tcp_start_server(void)
142 printf("Using %s device\n", eth_get_name());
143 printf("Listening for fastboot command on tcp %pI4\n", &net_ip);
145 tcp_set_tcp_handler(fastboot_tcp_handler_ipv4);