mirror of
https://github.com/Noratrieb/cluelessh.git
synced 2026-01-15 17:05:05 +01:00
refactor
This commit is contained in:
parent
d34db09fd1
commit
c0f9687696
11 changed files with 529 additions and 505 deletions
4
Cargo.lock
generated
4
Cargo.lock
generated
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@ -915,6 +915,10 @@ dependencies = [
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"der",
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"der",
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]
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]
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[[package]]
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name = "ssh"
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version = "0.1.0"
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[[package]]
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[[package]]
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name = "ssh-connection"
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name = "ssh-connection"
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version = "0.1.0"
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version = "0.1.0"
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@ -1,5 +1,5 @@
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[workspace]
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[workspace]
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members = ["fakesshd", "ssh-connection", "ssh-protocol", "ssh-transport"]
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members = ["fakesshd", "ssh", "ssh-connection", "ssh-protocol", "ssh-transport"]
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resolver = "2"
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resolver = "2"
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[workspace.dependencies]
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[workspace.dependencies]
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3
fakesshd/README.md
Normal file
3
fakesshd/README.md
Normal file
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@ -0,0 +1,3 @@
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# fakesshd
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An SSH honeypot.
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@ -101,7 +101,7 @@ async fn handle_connection(
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}
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}
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}*/
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}*/
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let mut state = ServerConnection::new(transport::ServerConnection::new(ThreadRngRand));
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let mut state = ServerConnection::new(transport::server::ServerConnection::new(ThreadRngRand));
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let mut session_channels = HashMap::new();
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let mut session_channels = HashMap::new();
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@ -5,7 +5,7 @@ pub use ssh_transport as transport;
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pub use ssh_transport::{Result, SshStatus};
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pub use ssh_transport::{Result, SshStatus};
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pub struct ServerConnection {
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pub struct ServerConnection {
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transport: ssh_transport::ServerConnection,
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transport: ssh_transport::server::ServerConnection,
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state: ServerConnectionState,
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state: ServerConnectionState,
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}
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}
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@ -15,7 +15,7 @@ enum ServerConnectionState {
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}
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}
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impl ServerConnection {
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impl ServerConnection {
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pub fn new(transport: ssh_transport::ServerConnection) -> Self {
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pub fn new(transport: ssh_transport::server::ServerConnection) -> Self {
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Self {
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Self {
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transport,
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transport,
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state: ServerConnectionState::Auth(auth::BadAuth::new()),
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state: ServerConnectionState::Auth(auth::BadAuth::new()),
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@ -2,15 +2,7 @@ mod crypto;
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pub mod numbers;
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pub mod numbers;
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pub mod packet;
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pub mod packet;
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pub mod parse;
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pub mod parse;
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pub mod server;
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use core::str;
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use std::{collections::VecDeque, mem::take};
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use crypto::{AlgorithmName, AlgorithmNegotiation, EncryptionAlgorithm, HostKeySigningAlgorithm};
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use packet::{KeyExchangeEcDhInitPacket, KeyExchangeInitPacket, Packet, PacketTransport};
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use parse::{NameList, Parser, Writer};
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use sha2::Digest;
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use tracing::{debug, info, trace};
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pub use packet::Msg;
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pub use packet::Msg;
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@ -37,43 +29,6 @@ impl From<eyre::Report> for SshStatus {
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}
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}
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}
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}
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// This is definitely who we are.
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pub const SERVER_IDENTIFICATION: &[u8] = b"SSH-2.0-OpenSSH_9.7\r\n";
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pub struct ServerConnection {
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state: ServerState,
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packet_transport: PacketTransport,
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rng: Box<dyn SshRng + Send + Sync>,
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plaintext_packets: VecDeque<Packet>,
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}
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enum ServerState {
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ProtoExchange {
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received: Vec<u8>,
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},
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KeyExchangeInit {
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client_identification: Vec<u8>,
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},
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DhKeyInit {
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client_identification: Vec<u8>,
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client_kexinit: Vec<u8>,
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server_kexinit: Vec<u8>,
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kex_algorithm: crypto::KexAlgorithm,
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server_host_key_algorithm: HostKeySigningAlgorithm,
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encryption_client_to_server: EncryptionAlgorithm,
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encryption_server_to_client: EncryptionAlgorithm,
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},
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NewKeys {
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h: [u8; 32],
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k: Vec<u8>,
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encryption_client_to_server: EncryptionAlgorithm,
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encryption_server_to_client: EncryptionAlgorithm,
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},
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ServiceRequest,
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Open,
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}
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pub trait SshRng {
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pub trait SshRng {
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fn fill_bytes(&mut self, dest: &mut [u8]);
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fn fill_bytes(&mut self, dest: &mut [u8]);
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}
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}
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@ -98,460 +53,9 @@ impl rand_core::RngCore for SshRngRandAdapter<'_> {
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}
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}
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}
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}
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impl ServerConnection {
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pub fn new(rng: impl SshRng + Send + Sync + 'static) -> Self {
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Self {
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state: ServerState::ProtoExchange {
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received: Vec::new(),
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},
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packet_transport: PacketTransport::new(),
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rng: Box::new(rng),
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plaintext_packets: VecDeque::new(),
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}
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}
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}
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impl ServerConnection {
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pub fn recv_bytes(&mut self, bytes: &[u8]) -> Result<()> {
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if let ServerState::ProtoExchange { received } = &mut self.state {
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received.extend_from_slice(bytes);
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if received.windows(2).any(|win| win == b"\r\n") {
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// TODO: care that its SSH 2.0 instead of anythin anything else
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// The client will not send any more information than this until we respond, so discord the rest of the bytes.
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let client_identification = received.to_owned();
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let client_ident_string = String::from_utf8_lossy(&client_identification);
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debug!(identification = %client_ident_string, "Client identifier");
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self.packet_transport.queue_send_protocol_info();
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self.state = ServerState::KeyExchangeInit {
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client_identification,
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};
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}
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// This means that we must be called at least twice, which is fine I think.
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return Ok(());
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}
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self.packet_transport.recv_bytes(bytes)?;
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while let Some(packet) = self.packet_transport.recv_next_packet() {
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let packet_type = packet.payload.get(0).unwrap_or(&0xFF);
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let packet_type_string =
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numbers::packet_type_to_string(*packet_type).unwrap_or("<unknown>");
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trace!(%packet_type, %packet_type_string, packet_len = %packet.payload.len(), "Received packet");
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// Handle some packets ignoring the state.
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match packet.payload.get(0).copied() {
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Some(numbers::SSH_MSG_DISCONNECT) => {
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// <https://datatracker.ietf.org/doc/html/rfc4253#section-11.1>
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let mut disconnect = Parser::new(&packet.payload[1..]);
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let reason = disconnect.u32()?;
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let description = disconnect.utf8_string()?;
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let _language_tag = disconnect.utf8_string()?;
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let reason_string =
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numbers::disconnect_reason_to_string(reason).unwrap_or("<unknown>");
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info!(%reason, %reason_string, %description, "Client disconnecting");
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return Err(SshStatus::Disconnect);
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}
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_ => {}
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}
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match &mut self.state {
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ServerState::ProtoExchange { .. } => unreachable!("handled above"),
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ServerState::KeyExchangeInit {
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client_identification,
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} => {
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let kex = KeyExchangeInitPacket::parse(&packet.payload)?;
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let require_algorithm =
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|expected: &'static str, list: NameList<'_>| -> Result<&'static str> {
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if list.iter().any(|alg| alg == expected) {
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Ok(expected)
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} else {
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Err(client_error!(
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"client does not support algorithm {expected}. supported: {list:?}",
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))
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}
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};
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let kex_algorithms = AlgorithmNegotiation {
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supported: vec![
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crypto::KEX_CURVE_25519_SHA256,
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crypto::KEX_ECDH_SHA2_NISTP256,
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],
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};
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let kex_algorithm = kex_algorithms.find(kex.kex_algorithms.0)?;
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debug!(name = %kex_algorithm.name(), "Using KEX algorithm");
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let hostkey_algorithms = AlgorithmNegotiation {
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supported: vec![
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crypto::hostkey_ed25519(ED25519_PRIVKEY_BYTES.to_vec()),
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crypto::hostkey_ecdsa_sha2_p256(ECDSA_P256_PRIVKEY_BYTES.to_vec()),
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],
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};
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let server_host_key_algorithm =
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hostkey_algorithms.find(kex.server_host_key_algorithms.0)?;
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debug!(name = %server_host_key_algorithm.name(), "Using host key algorithm");
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// TODO: Implement aes128-ctr
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let _ = crypto::encrypt::ENC_AES128_CTR;
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let encryption_algorithms_client_to_server = AlgorithmNegotiation {
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supported: vec![
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crypto::encrypt::CHACHA20POLY1305,
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crypto::encrypt::AES256_GCM,
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],
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};
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let encryption_algorithms_server_to_client = AlgorithmNegotiation {
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supported: vec![
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crypto::encrypt::CHACHA20POLY1305,
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crypto::encrypt::AES256_GCM,
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],
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};
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let encryption_client_to_server = encryption_algorithms_client_to_server
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.find(kex.encryption_algorithms_client_to_server.0)?;
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debug!(name = %encryption_client_to_server.name(), "Using encryption algorithm C->S");
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let encryption_server_to_client = encryption_algorithms_server_to_client
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.find(kex.encryption_algorithms_server_to_client.0)?;
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debug!(name = %encryption_server_to_client.name(), "Using encryption algorithm S->C");
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let mac_algorithm_client_to_server =
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require_algorithm("hmac-sha2-256", kex.mac_algorithms_client_to_server)?;
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let mac_algorithm_server_to_client =
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require_algorithm("hmac-sha2-256", kex.mac_algorithms_server_to_client)?;
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let compression_algorithm_client_to_server =
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require_algorithm("none", kex.compression_algorithms_client_to_server)?;
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let compression_algorithm_server_to_client =
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require_algorithm("none", kex.compression_algorithms_server_to_client)?;
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let _ = kex.languages_client_to_server;
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let _ = kex.languages_server_to_client;
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if kex.first_kex_packet_follows {
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return Err(client_error!(
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"the client wants to send a guessed packet, that's annoying :("
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));
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}
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let mut cookie = [0; 16];
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self.rng.fill_bytes(&mut cookie);
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let server_kexinit = KeyExchangeInitPacket {
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cookie,
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kex_algorithms: NameList::one(kex_algorithm.name()),
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server_host_key_algorithms: NameList::one(server_host_key_algorithm.name()),
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encryption_algorithms_client_to_server: NameList::one(
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encryption_client_to_server.name(),
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),
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encryption_algorithms_server_to_client: NameList::one(
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encryption_server_to_client.name(),
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),
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mac_algorithms_client_to_server: NameList::one(
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mac_algorithm_client_to_server,
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),
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mac_algorithms_server_to_client: NameList::one(
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mac_algorithm_server_to_client,
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),
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compression_algorithms_client_to_server: NameList::one(
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compression_algorithm_client_to_server,
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),
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compression_algorithms_server_to_client: NameList::one(
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compression_algorithm_server_to_client,
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),
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languages_client_to_server: NameList::none(),
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languages_server_to_client: NameList::none(),
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first_kex_packet_follows: false,
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};
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let client_identification = take(client_identification);
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let server_kexinit_payload = server_kexinit.to_bytes();
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self.packet_transport.queue_packet(Packet {
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payload: server_kexinit_payload.clone(),
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});
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self.state = ServerState::DhKeyInit {
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client_identification,
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client_kexinit: packet.payload,
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server_kexinit: server_kexinit_payload,
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kex_algorithm,
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server_host_key_algorithm,
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encryption_client_to_server,
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encryption_server_to_client,
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};
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}
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ServerState::DhKeyInit {
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client_identification,
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client_kexinit,
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server_kexinit,
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kex_algorithm,
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server_host_key_algorithm,
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encryption_client_to_server,
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encryption_server_to_client,
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} => {
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let dh = KeyExchangeEcDhInitPacket::parse(&packet.payload)?;
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let client_public_key = dh.qc;
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let crypto::KexAlgorithmOutput {
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server_public_key,
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shared_secret,
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} = (kex_algorithm.exchange)(client_public_key, &mut *self.rng)?;
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let pub_hostkey = server_host_key_algorithm.public_key();
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let mut hash = sha2::Sha256::new();
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let add_hash = |hash: &mut sha2::Sha256, bytes: &[u8]| {
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hash.update(bytes);
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};
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let hash_string = |hash: &mut sha2::Sha256, bytes: &[u8]| {
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add_hash(hash, &u32::to_be_bytes(bytes.len() as u32));
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add_hash(hash, bytes);
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};
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let hash_mpint = |hash: &mut sha2::Sha256, bytes: &[u8]| {
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crypto::encode_mpint_for_hash(bytes, |data| add_hash(hash, data));
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};
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hash_string(
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&mut hash,
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&client_identification[..(client_identification.len() - 2)],
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); // V_C
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hash_string(
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&mut hash,
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&SERVER_IDENTIFICATION[..(SERVER_IDENTIFICATION.len() - 2)],
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); // V_S
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hash_string(&mut hash, client_kexinit); // I_C
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hash_string(&mut hash, server_kexinit); // I_S
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hash_string(&mut hash, &pub_hostkey.0); // K_S
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// For normal DH as in RFC4253, e and f are mpints.
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// But for ECDH as defined in RFC5656, Q_C and Q_S are strings.
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// <https://datatracker.ietf.org/doc/html/rfc5656#section-4>
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hash_string(&mut hash, client_public_key); // Q_C
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hash_string(&mut hash, &server_public_key); // Q_S
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hash_mpint(&mut hash, &shared_secret); // K
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let hash = hash.finalize();
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let signature = server_host_key_algorithm.sign(&hash);
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// eprintln!("client_public_key: {:x?}", client_public_key.0);
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// eprintln!("server_public_key: {:x?}", server_public_key.as_bytes());
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// eprintln!("shared_secret: {:x?}", shared_secret.as_bytes());
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|
||||||
// eprintln!("hash: {:x?}", hash);
|
|
||||||
|
|
||||||
let packet = Packet::new_msg_kex_ecdh_reply(
|
|
||||||
&pub_hostkey.0,
|
|
||||||
&server_public_key,
|
|
||||||
&signature.0,
|
|
||||||
);
|
|
||||||
|
|
||||||
self.packet_transport.queue_packet(packet);
|
|
||||||
self.state = ServerState::NewKeys {
|
|
||||||
h: hash.into(),
|
|
||||||
k: shared_secret,
|
|
||||||
encryption_client_to_server: *encryption_client_to_server,
|
|
||||||
encryption_server_to_client: *encryption_server_to_client,
|
|
||||||
};
|
|
||||||
}
|
|
||||||
ServerState::NewKeys {
|
|
||||||
h,
|
|
||||||
k,
|
|
||||||
encryption_client_to_server,
|
|
||||||
encryption_server_to_client,
|
|
||||||
} => {
|
|
||||||
if packet.payload != [numbers::SSH_MSG_NEWKEYS] {
|
|
||||||
return Err(client_error!("did not send SSH_MSG_NEWKEYS"));
|
|
||||||
}
|
|
||||||
|
|
||||||
self.packet_transport.queue_packet(Packet {
|
|
||||||
payload: vec![numbers::SSH_MSG_NEWKEYS],
|
|
||||||
});
|
|
||||||
self.packet_transport.set_key(
|
|
||||||
*h,
|
|
||||||
k,
|
|
||||||
*encryption_client_to_server,
|
|
||||||
*encryption_server_to_client,
|
|
||||||
);
|
|
||||||
self.state = ServerState::ServiceRequest {};
|
|
||||||
}
|
|
||||||
ServerState::ServiceRequest => {
|
|
||||||
// TODO: this should probably move out of here? unsure.
|
|
||||||
if packet.payload.first() != Some(&numbers::SSH_MSG_SERVICE_REQUEST) {
|
|
||||||
return Err(client_error!("did not send SSH_MSG_SERVICE_REQUEST"));
|
|
||||||
}
|
|
||||||
let mut p = Parser::new(&packet.payload[1..]);
|
|
||||||
let service = p.utf8_string()?;
|
|
||||||
debug!(%service, "Client requesting service");
|
|
||||||
|
|
||||||
if service != "ssh-userauth" {
|
|
||||||
return Err(client_error!("only supports ssh-userauth"));
|
|
||||||
}
|
|
||||||
|
|
||||||
self.packet_transport.queue_packet(Packet {
|
|
||||||
payload: {
|
|
||||||
let mut writer = Writer::new();
|
|
||||||
writer.u8(numbers::SSH_MSG_SERVICE_ACCEPT);
|
|
||||||
writer.string(service.as_bytes());
|
|
||||||
writer.finish()
|
|
||||||
},
|
|
||||||
});
|
|
||||||
self.state = ServerState::Open;
|
|
||||||
}
|
|
||||||
ServerState::Open => {
|
|
||||||
self.plaintext_packets.push_back(packet);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
Ok(())
|
|
||||||
}
|
|
||||||
|
|
||||||
pub fn next_msg_to_send(&mut self) -> Option<Msg> {
|
|
||||||
self.packet_transport.next_msg_to_send()
|
|
||||||
}
|
|
||||||
|
|
||||||
pub fn next_plaintext_packet(&mut self) -> Option<Packet> {
|
|
||||||
self.plaintext_packets.pop_front()
|
|
||||||
}
|
|
||||||
|
|
||||||
pub fn send_plaintext_packet(&mut self, packet: Packet) {
|
|
||||||
self.packet_transport.queue_packet(packet);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Manually extracted from the key using <https://peterlyons.com/problog/2017/12/openssh-ed25519-private-key-file-format/>, probably wrong
|
|
||||||
/// ```text
|
|
||||||
/// ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOk5zfpvwNc3MztTTpE90zLI1Ref4AwwRVdSFyJLGbj2 testkey
|
|
||||||
/// ```
|
|
||||||
/// ```text
|
|
||||||
/// -----BEGIN OPENSSH PRIVATE KEY-----
|
|
||||||
/// b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAAAMwAAAAtzc2gtZW
|
|
||||||
/// QyNTUxOQAAACDpOc36b8DXNzM7U06RPdMyyNUXn+AMMEVXUhciSxm49gAAAJDpgLSk6YC0
|
|
||||||
/// pAAAAAtzc2gtZWQyNTUxOQAAACDpOc36b8DXNzM7U06RPdMyyNUXn+AMMEVXUhciSxm49g
|
|
||||||
/// AAAECSeskxuEtJrr9L7ZkbpogXC5pKRNVHx1ueMX2h1XUnmek5zfpvwNc3MztTTpE90zLI
|
|
||||||
/// 1Ref4AwwRVdSFyJLGbj2AAAAB3Rlc3RrZXkBAgMEBQY=
|
|
||||||
/// -----END OPENSSH PRIVATE KEY-----
|
|
||||||
/// ```
|
|
||||||
const ED25519_PRIVKEY_BYTES: &[u8; 32] = &[
|
|
||||||
0x92, 0x7a, 0xc9, 0x31, 0xb8, 0x4b, 0x49, 0xae, 0xbf, 0x4b, 0xed, 0x99, 0x1b, 0xa6, 0x88, 0x17,
|
|
||||||
0x0b, 0x9a, 0x4a, 0x44, 0xd5, 0x47, 0xc7, 0x5b, 0x9e, 0x31, 0x7d, 0xa1, 0xd5, 0x75, 0x27, 0x99,
|
|
||||||
];
|
|
||||||
|
|
||||||
const ECDSA_P256_PRIVKEY_BYTES: &[u8; 32] = &[
|
|
||||||
0x89, 0xdd, 0x0c, 0x96, 0x22, 0x85, 0x10, 0xec, 0x3c, 0xa4, 0xa1, 0xb8, 0xac, 0x2a, 0x77, 0xa8,
|
|
||||||
0xd4, 0x4d, 0xcb, 0x9d, 0x90, 0x25, 0xc6, 0xd8, 0x3a, 0x02, 0x74, 0x4f, 0x9e, 0x44, 0xcd, 0xa3,
|
|
||||||
];
|
|
||||||
|
|
||||||
#[macro_export]
|
#[macro_export]
|
||||||
macro_rules! client_error {
|
macro_rules! client_error {
|
||||||
($($tt:tt)*) => {
|
($($tt:tt)*) => {
|
||||||
$crate::SshStatus::ClientError(::std::format!($($tt)*))
|
$crate::SshStatus::ClientError(::std::format!($($tt)*))
|
||||||
};
|
};
|
||||||
}
|
}
|
||||||
|
|
||||||
#[cfg(test)]
|
|
||||||
mod tests {
|
|
||||||
use hex_literal::hex;
|
|
||||||
|
|
||||||
use crate::{packet::MsgKind, ServerConnection, SshRng};
|
|
||||||
|
|
||||||
struct NoRng;
|
|
||||||
impl SshRng for NoRng {
|
|
||||||
fn fill_bytes(&mut self, _: &mut [u8]) {
|
|
||||||
unreachable!()
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
struct HardcodedRng(Vec<u8>);
|
|
||||||
impl SshRng for HardcodedRng {
|
|
||||||
fn fill_bytes(&mut self, dest: &mut [u8]) {
|
|
||||||
dest.copy_from_slice(&self.0[..dest.len()]);
|
|
||||||
self.0.splice(0..dest.len(), []);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
#[test]
|
|
||||||
fn protocol_exchange() {
|
|
||||||
let mut con = ServerConnection::new(NoRng);
|
|
||||||
con.recv_bytes(b"SSH-2.0-OpenSSH_9.7\r\n").unwrap();
|
|
||||||
let msg = con.next_msg_to_send().unwrap();
|
|
||||||
assert_eq!(msg.0, MsgKind::ServerProtocolInfo);
|
|
||||||
}
|
|
||||||
|
|
||||||
#[test]
|
|
||||||
fn protocol_exchange_slow_client() {
|
|
||||||
let mut con = ServerConnection::new(NoRng);
|
|
||||||
con.recv_bytes(b"SSH-2.0-").unwrap();
|
|
||||||
con.recv_bytes(b"OpenSSH_9.7\r\n").unwrap();
|
|
||||||
let msg = con.next_msg_to_send().unwrap();
|
|
||||||
assert_eq!(msg.0, MsgKind::ServerProtocolInfo);
|
|
||||||
}
|
|
||||||
|
|
||||||
#[test]
|
|
||||||
fn handshake() {
|
|
||||||
#[rustfmt::skip]
|
|
||||||
let rng = vec![
|
|
||||||
0x14, 0xa2, 0x04, 0xa5, 0x4b, 0x2f, 0x5f, 0xa7, 0xff, 0x53, 0x13, 0x67, 0x57, 0x67, 0xbc,
|
|
||||||
0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75, 0x95, 0x18, 0x4b, 0xd2, 0xcb, 0xd0,
|
|
||||||
0x64, 0x06, 0x14, 0xa2, 0x04, 0xa5, 0x4b, 0x2f, 0x5f, 0xa7, 0xff, 0x53, 0x13, 0x67, 0x57,
|
|
||||||
0x67, 0xbc, 0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75, 0x95, 0x18, 0x4b, 0xd2,
|
|
||||||
0xcb, 0xd0, 0x64, 0x06, 0x67, 0xbc, 0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75,
|
|
||||||
0x95, 0x18, 0x4b, 0xd2, 0xcb, 0xd0, 0x64, 0x06,
|
|
||||||
];
|
|
||||||
struct Part {
|
|
||||||
client: &'static [u8],
|
|
||||||
server: &'static [u8],
|
|
||||||
}
|
|
||||||
|
|
||||||
// Extracted from a real OpenSSH client using this server (with hardcoded creds) using Wireshark.
|
|
||||||
let conversation = [
|
|
||||||
Part {
|
|
||||||
client: &hex!("5353482d322e302d4f70656e5353485f392e370d0a"),
|
|
||||||
server: &hex!("5353482d322e302d4f70656e5353485f392e370d0a"),
|
|
||||||
},
|
|
||||||
// KEX Init
|
|
||||||
Part {
|
|
||||||
client: &hex!(
|
|
||||||
"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"
|
|
||||||
),
|
|
||||||
server: &hex!(
|
|
||||||
"000000bc051414a204a54b2f5fa7ff5313675767bc5500000011637572766532353531392d7368613235360000000b7373682d656432353531390000001d63686163686132302d706f6c7931333035406f70656e7373682e636f6d0000001d63686163686132302d706f6c7931333035406f70656e7373682e636f6d0000000d686d61632d736861322d3235360000000d686d61632d736861322d323536000000046e6f6e65000000046e6f6e65000000000000000000000000000000000000"
|
|
||||||
),
|
|
||||||
},
|
|
||||||
// ECDH KEX Init
|
|
||||||
Part {
|
|
||||||
client: &hex!(
|
|
||||||
"0000002c061e000000204c646d1281abf23264d63db96e05c0223cfead668d9d38c62579b8856e67ae19000000000000"
|
|
||||||
),
|
|
||||||
server: &hex!(
|
|
||||||
"000000bc081f000000330000000b7373682d6564323535313900000020e939cdfa6fc0d737333b534e913dd332c8d5179fe00c3045575217224b19b8f6000000204260e2c5e5383f1a021c9631fa61f60f305b29183fd219d4c8207c664e063410000000530000000b7373682d65643235353139000000406504a045499f26aa4ee17606ea6bd9e3f288838591f25d8604a63f77a52f5b9e909c00d10f386553e585d86ab329bbde0fca5c64b1b1982d7adcac17cf7f06010000000000000000"
|
|
||||||
),
|
|
||||||
},
|
|
||||||
// New Keys
|
|
||||||
Part {
|
|
||||||
client: &hex!("0000000c0a1500000000000000000000"),
|
|
||||||
server: &hex!("0000000c0a1500000000000000000000"),
|
|
||||||
},
|
|
||||||
// Service Request (encrypted)
|
|
||||||
Part {
|
|
||||||
client: &hex!("09ca4db7baeb24836a1f7d22368055bf4c26981ed86738ac7a5c31d0730ad656f1967853781dff91ee1c4de8"),
|
|
||||||
server: &hex!("7b444c0d5faf740d350701a054ea469fab1c98e4b669e4872a454163edb42ec5e4fa95c404ab601f016bd259"),
|
|
||||||
},
|
|
||||||
];
|
|
||||||
|
|
||||||
let mut con = ServerConnection::new(HardcodedRng(rng));
|
|
||||||
for part in conversation {
|
|
||||||
con.recv_bytes(&part.client).unwrap();
|
|
||||||
eprintln!("client: {:x?}", part.client);
|
|
||||||
let bytes = con.next_msg_to_send().unwrap().to_bytes();
|
|
||||||
if part.server != bytes {
|
|
||||||
panic!(
|
|
||||||
"expected != found\nexpected: {:x?}\nfound: {:x?}",
|
|
||||||
part.server, bytes
|
|
||||||
);
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
|
||||||
|
|
@ -24,7 +24,7 @@ pub struct Msg(pub(crate) MsgKind);
|
||||||
|
|
||||||
#[derive(Debug, PartialEq)]
|
#[derive(Debug, PartialEq)]
|
||||||
pub(crate) enum MsgKind {
|
pub(crate) enum MsgKind {
|
||||||
ServerProtocolInfo,
|
ServerProtocolInfo(Vec<u8>),
|
||||||
PlaintextPacket(Packet),
|
PlaintextPacket(Packet),
|
||||||
EncryptedPacket(EncryptedPacket),
|
EncryptedPacket(EncryptedPacket),
|
||||||
}
|
}
|
||||||
|
|
@ -32,7 +32,7 @@ pub(crate) enum MsgKind {
|
||||||
impl Msg {
|
impl Msg {
|
||||||
pub fn to_bytes(self) -> Vec<u8> {
|
pub fn to_bytes(self) -> Vec<u8> {
|
||||||
match self.0 {
|
match self.0 {
|
||||||
MsgKind::ServerProtocolInfo => crate::SERVER_IDENTIFICATION.to_vec(),
|
MsgKind::ServerProtocolInfo(v) => v,
|
||||||
MsgKind::PlaintextPacket(v) => v.to_bytes(true, Packet::DEFAULT_BLOCK_SIZE),
|
MsgKind::PlaintextPacket(v) => v.to_bytes(true, Packet::DEFAULT_BLOCK_SIZE),
|
||||||
MsgKind::EncryptedPacket(v) => v.into_bytes(),
|
MsgKind::EncryptedPacket(v) => v.into_bytes(),
|
||||||
}
|
}
|
||||||
|
|
@ -85,8 +85,8 @@ impl PacketTransport {
|
||||||
self.queue_send_msg(msg);
|
self.queue_send_msg(msg);
|
||||||
}
|
}
|
||||||
|
|
||||||
pub(crate) fn queue_send_protocol_info(&mut self) {
|
pub(crate) fn queue_send_protocol_info(&mut self, identification: Vec<u8>) {
|
||||||
self.queue_send_msg(Msg(MsgKind::ServerProtocolInfo));
|
self.queue_send_msg(Msg(MsgKind::ServerProtocolInfo(identification)));
|
||||||
}
|
}
|
||||||
|
|
||||||
pub(crate) fn recv_next_packet(&mut self) -> Option<Packet> {
|
pub(crate) fn recv_next_packet(&mut self) -> Option<Packet> {
|
||||||
|
|
|
||||||
501
ssh-transport/src/server.rs
Normal file
501
ssh-transport/src/server.rs
Normal file
|
|
@ -0,0 +1,501 @@
|
||||||
|
use core::str;
|
||||||
|
use std::{collections::VecDeque, mem::take};
|
||||||
|
|
||||||
|
use crate::crypto::{
|
||||||
|
self, AlgorithmName, AlgorithmNegotiation, EncryptionAlgorithm, HostKeySigningAlgorithm,
|
||||||
|
};
|
||||||
|
use crate::packet::{KeyExchangeEcDhInitPacket, KeyExchangeInitPacket, Packet, PacketTransport};
|
||||||
|
use crate::parse::{NameList, Parser, Writer};
|
||||||
|
use crate::{client_error, Msg, SshRng, SshStatus};
|
||||||
|
use crate::{numbers, Result};
|
||||||
|
use sha2::Digest;
|
||||||
|
use tracing::{debug, info, trace};
|
||||||
|
|
||||||
|
// This is definitely who we are.
|
||||||
|
pub const SERVER_IDENTIFICATION: &[u8] = b"SSH-2.0-OpenSSH_9.7\r\n";
|
||||||
|
|
||||||
|
pub struct ServerConnection {
|
||||||
|
state: ServerState,
|
||||||
|
packet_transport: PacketTransport,
|
||||||
|
rng: Box<dyn SshRng + Send + Sync>,
|
||||||
|
|
||||||
|
plaintext_packets: VecDeque<Packet>,
|
||||||
|
}
|
||||||
|
|
||||||
|
enum ServerState {
|
||||||
|
ProtoExchange {
|
||||||
|
received: Vec<u8>,
|
||||||
|
},
|
||||||
|
KeyExchangeInit {
|
||||||
|
client_identification: Vec<u8>,
|
||||||
|
},
|
||||||
|
DhKeyInit {
|
||||||
|
client_identification: Vec<u8>,
|
||||||
|
client_kexinit: Vec<u8>,
|
||||||
|
server_kexinit: Vec<u8>,
|
||||||
|
kex_algorithm: crypto::KexAlgorithm,
|
||||||
|
server_host_key_algorithm: HostKeySigningAlgorithm,
|
||||||
|
encryption_client_to_server: EncryptionAlgorithm,
|
||||||
|
encryption_server_to_client: EncryptionAlgorithm,
|
||||||
|
},
|
||||||
|
NewKeys {
|
||||||
|
h: [u8; 32],
|
||||||
|
k: Vec<u8>,
|
||||||
|
encryption_client_to_server: EncryptionAlgorithm,
|
||||||
|
encryption_server_to_client: EncryptionAlgorithm,
|
||||||
|
},
|
||||||
|
ServiceRequest,
|
||||||
|
Open,
|
||||||
|
}
|
||||||
|
|
||||||
|
impl ServerConnection {
|
||||||
|
pub fn new(rng: impl SshRng + Send + Sync + 'static) -> Self {
|
||||||
|
Self {
|
||||||
|
state: ServerState::ProtoExchange {
|
||||||
|
received: Vec::new(),
|
||||||
|
},
|
||||||
|
packet_transport: PacketTransport::new(),
|
||||||
|
rng: Box::new(rng),
|
||||||
|
|
||||||
|
plaintext_packets: VecDeque::new(),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl ServerConnection {
|
||||||
|
pub fn recv_bytes(&mut self, bytes: &[u8]) -> Result<()> {
|
||||||
|
if let ServerState::ProtoExchange { received } = &mut self.state {
|
||||||
|
received.extend_from_slice(bytes);
|
||||||
|
if received.windows(2).any(|win| win == b"\r\n") {
|
||||||
|
// TODO: care that its SSH 2.0 instead of anythin anything else
|
||||||
|
// The client will not send any more information than this until we respond, so discord the rest of the bytes.
|
||||||
|
let client_identification = received.to_owned();
|
||||||
|
let client_ident_string = String::from_utf8_lossy(&client_identification);
|
||||||
|
debug!(identification = %client_ident_string, "Client identifier");
|
||||||
|
self.packet_transport
|
||||||
|
.queue_send_protocol_info(SERVER_IDENTIFICATION.to_vec());
|
||||||
|
self.state = ServerState::KeyExchangeInit {
|
||||||
|
client_identification,
|
||||||
|
};
|
||||||
|
}
|
||||||
|
// This means that we must be called at least twice, which is fine I think.
|
||||||
|
return Ok(());
|
||||||
|
}
|
||||||
|
|
||||||
|
self.packet_transport.recv_bytes(bytes)?;
|
||||||
|
|
||||||
|
while let Some(packet) = self.packet_transport.recv_next_packet() {
|
||||||
|
let packet_type = packet.payload.get(0).unwrap_or(&0xFF);
|
||||||
|
let packet_type_string =
|
||||||
|
numbers::packet_type_to_string(*packet_type).unwrap_or("<unknown>");
|
||||||
|
|
||||||
|
trace!(%packet_type, %packet_type_string, packet_len = %packet.payload.len(), "Received packet");
|
||||||
|
|
||||||
|
// Handle some packets ignoring the state.
|
||||||
|
match packet.payload.get(0).copied() {
|
||||||
|
Some(numbers::SSH_MSG_DISCONNECT) => {
|
||||||
|
// <https://datatracker.ietf.org/doc/html/rfc4253#section-11.1>
|
||||||
|
let mut disconnect = Parser::new(&packet.payload[1..]);
|
||||||
|
let reason = disconnect.u32()?;
|
||||||
|
let description = disconnect.utf8_string()?;
|
||||||
|
let _language_tag = disconnect.utf8_string()?;
|
||||||
|
|
||||||
|
let reason_string =
|
||||||
|
numbers::disconnect_reason_to_string(reason).unwrap_or("<unknown>");
|
||||||
|
|
||||||
|
info!(%reason, %reason_string, %description, "Client disconnecting");
|
||||||
|
|
||||||
|
return Err(SshStatus::Disconnect);
|
||||||
|
}
|
||||||
|
_ => {}
|
||||||
|
}
|
||||||
|
|
||||||
|
match &mut self.state {
|
||||||
|
ServerState::ProtoExchange { .. } => unreachable!("handled above"),
|
||||||
|
ServerState::KeyExchangeInit {
|
||||||
|
client_identification,
|
||||||
|
} => {
|
||||||
|
let kex = KeyExchangeInitPacket::parse(&packet.payload)?;
|
||||||
|
|
||||||
|
let require_algorithm =
|
||||||
|
|expected: &'static str, list: NameList<'_>| -> Result<&'static str> {
|
||||||
|
if list.iter().any(|alg| alg == expected) {
|
||||||
|
Ok(expected)
|
||||||
|
} else {
|
||||||
|
Err(client_error!(
|
||||||
|
"client does not support algorithm {expected}. supported: {list:?}",
|
||||||
|
))
|
||||||
|
}
|
||||||
|
};
|
||||||
|
|
||||||
|
let kex_algorithms = AlgorithmNegotiation {
|
||||||
|
supported: vec![
|
||||||
|
crypto::KEX_CURVE_25519_SHA256,
|
||||||
|
crypto::KEX_ECDH_SHA2_NISTP256,
|
||||||
|
],
|
||||||
|
};
|
||||||
|
let kex_algorithm = kex_algorithms.find(kex.kex_algorithms.0)?;
|
||||||
|
debug!(name = %kex_algorithm.name(), "Using KEX algorithm");
|
||||||
|
|
||||||
|
let hostkey_algorithms = AlgorithmNegotiation {
|
||||||
|
supported: vec![
|
||||||
|
crypto::hostkey_ed25519(ED25519_PRIVKEY_BYTES.to_vec()),
|
||||||
|
crypto::hostkey_ecdsa_sha2_p256(ECDSA_P256_PRIVKEY_BYTES.to_vec()),
|
||||||
|
],
|
||||||
|
};
|
||||||
|
let server_host_key_algorithm =
|
||||||
|
hostkey_algorithms.find(kex.server_host_key_algorithms.0)?;
|
||||||
|
debug!(name = %server_host_key_algorithm.name(), "Using host key algorithm");
|
||||||
|
|
||||||
|
// TODO: Implement aes128-ctr
|
||||||
|
let _ = crypto::encrypt::ENC_AES128_CTR;
|
||||||
|
|
||||||
|
let encryption_algorithms_client_to_server = AlgorithmNegotiation {
|
||||||
|
supported: vec![
|
||||||
|
crypto::encrypt::CHACHA20POLY1305,
|
||||||
|
crypto::encrypt::AES256_GCM,
|
||||||
|
],
|
||||||
|
};
|
||||||
|
let encryption_algorithms_server_to_client = AlgorithmNegotiation {
|
||||||
|
supported: vec![
|
||||||
|
crypto::encrypt::CHACHA20POLY1305,
|
||||||
|
crypto::encrypt::AES256_GCM,
|
||||||
|
],
|
||||||
|
};
|
||||||
|
|
||||||
|
let encryption_client_to_server = encryption_algorithms_client_to_server
|
||||||
|
.find(kex.encryption_algorithms_client_to_server.0)?;
|
||||||
|
debug!(name = %encryption_client_to_server.name(), "Using encryption algorithm C->S");
|
||||||
|
|
||||||
|
let encryption_server_to_client = encryption_algorithms_server_to_client
|
||||||
|
.find(kex.encryption_algorithms_server_to_client.0)?;
|
||||||
|
debug!(name = %encryption_server_to_client.name(), "Using encryption algorithm S->C");
|
||||||
|
|
||||||
|
let mac_algorithm_client_to_server =
|
||||||
|
require_algorithm("hmac-sha2-256", kex.mac_algorithms_client_to_server)?;
|
||||||
|
let mac_algorithm_server_to_client =
|
||||||
|
require_algorithm("hmac-sha2-256", kex.mac_algorithms_server_to_client)?;
|
||||||
|
let compression_algorithm_client_to_server =
|
||||||
|
require_algorithm("none", kex.compression_algorithms_client_to_server)?;
|
||||||
|
let compression_algorithm_server_to_client =
|
||||||
|
require_algorithm("none", kex.compression_algorithms_server_to_client)?;
|
||||||
|
|
||||||
|
let _ = kex.languages_client_to_server;
|
||||||
|
let _ = kex.languages_server_to_client;
|
||||||
|
|
||||||
|
if kex.first_kex_packet_follows {
|
||||||
|
return Err(client_error!(
|
||||||
|
"the client wants to send a guessed packet, that's annoying :("
|
||||||
|
));
|
||||||
|
}
|
||||||
|
|
||||||
|
let mut cookie = [0; 16];
|
||||||
|
self.rng.fill_bytes(&mut cookie);
|
||||||
|
let server_kexinit = KeyExchangeInitPacket {
|
||||||
|
cookie,
|
||||||
|
kex_algorithms: NameList::one(kex_algorithm.name()),
|
||||||
|
server_host_key_algorithms: NameList::one(server_host_key_algorithm.name()),
|
||||||
|
encryption_algorithms_client_to_server: NameList::one(
|
||||||
|
encryption_client_to_server.name(),
|
||||||
|
),
|
||||||
|
encryption_algorithms_server_to_client: NameList::one(
|
||||||
|
encryption_server_to_client.name(),
|
||||||
|
),
|
||||||
|
mac_algorithms_client_to_server: NameList::one(
|
||||||
|
mac_algorithm_client_to_server,
|
||||||
|
),
|
||||||
|
mac_algorithms_server_to_client: NameList::one(
|
||||||
|
mac_algorithm_server_to_client,
|
||||||
|
),
|
||||||
|
compression_algorithms_client_to_server: NameList::one(
|
||||||
|
compression_algorithm_client_to_server,
|
||||||
|
),
|
||||||
|
compression_algorithms_server_to_client: NameList::one(
|
||||||
|
compression_algorithm_server_to_client,
|
||||||
|
),
|
||||||
|
languages_client_to_server: NameList::none(),
|
||||||
|
languages_server_to_client: NameList::none(),
|
||||||
|
first_kex_packet_follows: false,
|
||||||
|
};
|
||||||
|
|
||||||
|
let client_identification = take(client_identification);
|
||||||
|
let server_kexinit_payload = server_kexinit.to_bytes();
|
||||||
|
self.packet_transport.queue_packet(Packet {
|
||||||
|
payload: server_kexinit_payload.clone(),
|
||||||
|
});
|
||||||
|
self.state = ServerState::DhKeyInit {
|
||||||
|
client_identification,
|
||||||
|
client_kexinit: packet.payload,
|
||||||
|
server_kexinit: server_kexinit_payload,
|
||||||
|
kex_algorithm,
|
||||||
|
server_host_key_algorithm,
|
||||||
|
encryption_client_to_server,
|
||||||
|
encryption_server_to_client,
|
||||||
|
};
|
||||||
|
}
|
||||||
|
ServerState::DhKeyInit {
|
||||||
|
client_identification,
|
||||||
|
client_kexinit,
|
||||||
|
server_kexinit,
|
||||||
|
kex_algorithm,
|
||||||
|
server_host_key_algorithm,
|
||||||
|
encryption_client_to_server,
|
||||||
|
encryption_server_to_client,
|
||||||
|
} => {
|
||||||
|
let dh = KeyExchangeEcDhInitPacket::parse(&packet.payload)?;
|
||||||
|
|
||||||
|
let client_public_key = dh.qc;
|
||||||
|
|
||||||
|
let crypto::KexAlgorithmOutput {
|
||||||
|
server_public_key,
|
||||||
|
shared_secret,
|
||||||
|
} = (kex_algorithm.exchange)(client_public_key, &mut *self.rng)?;
|
||||||
|
|
||||||
|
let pub_hostkey = server_host_key_algorithm.public_key();
|
||||||
|
|
||||||
|
let mut hash = sha2::Sha256::new();
|
||||||
|
let add_hash = |hash: &mut sha2::Sha256, bytes: &[u8]| {
|
||||||
|
hash.update(bytes);
|
||||||
|
};
|
||||||
|
let hash_string = |hash: &mut sha2::Sha256, bytes: &[u8]| {
|
||||||
|
add_hash(hash, &u32::to_be_bytes(bytes.len() as u32));
|
||||||
|
add_hash(hash, bytes);
|
||||||
|
};
|
||||||
|
let hash_mpint = |hash: &mut sha2::Sha256, bytes: &[u8]| {
|
||||||
|
crypto::encode_mpint_for_hash(bytes, |data| add_hash(hash, data));
|
||||||
|
};
|
||||||
|
|
||||||
|
hash_string(
|
||||||
|
&mut hash,
|
||||||
|
&client_identification[..(client_identification.len() - 2)],
|
||||||
|
); // V_C
|
||||||
|
hash_string(
|
||||||
|
&mut hash,
|
||||||
|
&SERVER_IDENTIFICATION[..(SERVER_IDENTIFICATION.len() - 2)],
|
||||||
|
); // V_S
|
||||||
|
hash_string(&mut hash, client_kexinit); // I_C
|
||||||
|
hash_string(&mut hash, server_kexinit); // I_S
|
||||||
|
hash_string(&mut hash, &pub_hostkey.0); // K_S
|
||||||
|
|
||||||
|
// For normal DH as in RFC4253, e and f are mpints.
|
||||||
|
// But for ECDH as defined in RFC5656, Q_C and Q_S are strings.
|
||||||
|
// <https://datatracker.ietf.org/doc/html/rfc5656#section-4>
|
||||||
|
hash_string(&mut hash, client_public_key); // Q_C
|
||||||
|
hash_string(&mut hash, &server_public_key); // Q_S
|
||||||
|
hash_mpint(&mut hash, &shared_secret); // K
|
||||||
|
|
||||||
|
let hash = hash.finalize();
|
||||||
|
|
||||||
|
let signature = server_host_key_algorithm.sign(&hash);
|
||||||
|
|
||||||
|
// eprintln!("client_public_key: {:x?}", client_public_key.0);
|
||||||
|
// eprintln!("server_public_key: {:x?}", server_public_key.as_bytes());
|
||||||
|
// eprintln!("shared_secret: {:x?}", shared_secret.as_bytes());
|
||||||
|
// eprintln!("hash: {:x?}", hash);
|
||||||
|
|
||||||
|
let packet = Packet::new_msg_kex_ecdh_reply(
|
||||||
|
&pub_hostkey.0,
|
||||||
|
&server_public_key,
|
||||||
|
&signature.0,
|
||||||
|
);
|
||||||
|
|
||||||
|
self.packet_transport.queue_packet(packet);
|
||||||
|
self.state = ServerState::NewKeys {
|
||||||
|
h: hash.into(),
|
||||||
|
k: shared_secret,
|
||||||
|
encryption_client_to_server: *encryption_client_to_server,
|
||||||
|
encryption_server_to_client: *encryption_server_to_client,
|
||||||
|
};
|
||||||
|
}
|
||||||
|
ServerState::NewKeys {
|
||||||
|
h,
|
||||||
|
k,
|
||||||
|
encryption_client_to_server,
|
||||||
|
encryption_server_to_client,
|
||||||
|
} => {
|
||||||
|
if packet.payload != [numbers::SSH_MSG_NEWKEYS] {
|
||||||
|
return Err(client_error!("did not send SSH_MSG_NEWKEYS"));
|
||||||
|
}
|
||||||
|
|
||||||
|
self.packet_transport.queue_packet(Packet {
|
||||||
|
payload: vec![numbers::SSH_MSG_NEWKEYS],
|
||||||
|
});
|
||||||
|
self.packet_transport.set_key(
|
||||||
|
*h,
|
||||||
|
k,
|
||||||
|
*encryption_client_to_server,
|
||||||
|
*encryption_server_to_client,
|
||||||
|
);
|
||||||
|
self.state = ServerState::ServiceRequest {};
|
||||||
|
}
|
||||||
|
ServerState::ServiceRequest => {
|
||||||
|
// TODO: this should probably move out of here? unsure.
|
||||||
|
if packet.payload.first() != Some(&numbers::SSH_MSG_SERVICE_REQUEST) {
|
||||||
|
return Err(client_error!("did not send SSH_MSG_SERVICE_REQUEST"));
|
||||||
|
}
|
||||||
|
let mut p = Parser::new(&packet.payload[1..]);
|
||||||
|
let service = p.utf8_string()?;
|
||||||
|
debug!(%service, "Client requesting service");
|
||||||
|
|
||||||
|
if service != "ssh-userauth" {
|
||||||
|
return Err(client_error!("only supports ssh-userauth"));
|
||||||
|
}
|
||||||
|
|
||||||
|
self.packet_transport.queue_packet(Packet {
|
||||||
|
payload: {
|
||||||
|
let mut writer = Writer::new();
|
||||||
|
writer.u8(numbers::SSH_MSG_SERVICE_ACCEPT);
|
||||||
|
writer.string(service.as_bytes());
|
||||||
|
writer.finish()
|
||||||
|
},
|
||||||
|
});
|
||||||
|
self.state = ServerState::Open;
|
||||||
|
}
|
||||||
|
ServerState::Open => {
|
||||||
|
self.plaintext_packets.push_back(packet);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
Ok(())
|
||||||
|
}
|
||||||
|
|
||||||
|
pub fn next_msg_to_send(&mut self) -> Option<Msg> {
|
||||||
|
self.packet_transport.next_msg_to_send()
|
||||||
|
}
|
||||||
|
|
||||||
|
pub fn next_plaintext_packet(&mut self) -> Option<Packet> {
|
||||||
|
self.plaintext_packets.pop_front()
|
||||||
|
}
|
||||||
|
|
||||||
|
pub fn send_plaintext_packet(&mut self, packet: Packet) {
|
||||||
|
self.packet_transport.queue_packet(packet);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// Manually extracted from the key using <https://peterlyons.com/problog/2017/12/openssh-ed25519-private-key-file-format/>, probably wrong
|
||||||
|
/// ```text
|
||||||
|
/// ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIOk5zfpvwNc3MztTTpE90zLI1Ref4AwwRVdSFyJLGbj2 testkey
|
||||||
|
/// ```
|
||||||
|
/// ```text
|
||||||
|
/// -----BEGIN OPENSSH PRIVATE KEY-----
|
||||||
|
/// b3BlbnNzaC1rZXktdjEAAAAABG5vbmUAAAAEbm9uZQAAAAAAAAABAAAAMwAAAAtzc2gtZW
|
||||||
|
/// QyNTUxOQAAACDpOc36b8DXNzM7U06RPdMyyNUXn+AMMEVXUhciSxm49gAAAJDpgLSk6YC0
|
||||||
|
/// pAAAAAtzc2gtZWQyNTUxOQAAACDpOc36b8DXNzM7U06RPdMyyNUXn+AMMEVXUhciSxm49g
|
||||||
|
/// AAAECSeskxuEtJrr9L7ZkbpogXC5pKRNVHx1ueMX2h1XUnmek5zfpvwNc3MztTTpE90zLI
|
||||||
|
/// 1Ref4AwwRVdSFyJLGbj2AAAAB3Rlc3RrZXkBAgMEBQY=
|
||||||
|
/// -----END OPENSSH PRIVATE KEY-----
|
||||||
|
/// ```
|
||||||
|
const ED25519_PRIVKEY_BYTES: &[u8; 32] = &[
|
||||||
|
0x92, 0x7a, 0xc9, 0x31, 0xb8, 0x4b, 0x49, 0xae, 0xbf, 0x4b, 0xed, 0x99, 0x1b, 0xa6, 0x88, 0x17,
|
||||||
|
0x0b, 0x9a, 0x4a, 0x44, 0xd5, 0x47, 0xc7, 0x5b, 0x9e, 0x31, 0x7d, 0xa1, 0xd5, 0x75, 0x27, 0x99,
|
||||||
|
];
|
||||||
|
|
||||||
|
const ECDSA_P256_PRIVKEY_BYTES: &[u8; 32] = &[
|
||||||
|
0x89, 0xdd, 0x0c, 0x96, 0x22, 0x85, 0x10, 0xec, 0x3c, 0xa4, 0xa1, 0xb8, 0xac, 0x2a, 0x77, 0xa8,
|
||||||
|
0xd4, 0x4d, 0xcb, 0x9d, 0x90, 0x25, 0xc6, 0xd8, 0x3a, 0x02, 0x74, 0x4f, 0x9e, 0x44, 0xcd, 0xa3,
|
||||||
|
];
|
||||||
|
|
||||||
|
#[cfg(test)]
|
||||||
|
mod tests {
|
||||||
|
use hex_literal::hex;
|
||||||
|
|
||||||
|
use crate::{packet::MsgKind, server::ServerConnection, SshRng};
|
||||||
|
|
||||||
|
struct NoRng;
|
||||||
|
impl SshRng for NoRng {
|
||||||
|
fn fill_bytes(&mut self, _: &mut [u8]) {
|
||||||
|
unreachable!()
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
struct HardcodedRng(Vec<u8>);
|
||||||
|
impl SshRng for HardcodedRng {
|
||||||
|
fn fill_bytes(&mut self, dest: &mut [u8]) {
|
||||||
|
dest.copy_from_slice(&self.0[..dest.len()]);
|
||||||
|
self.0.splice(0..dest.len(), []);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn protocol_exchange() {
|
||||||
|
let mut con = ServerConnection::new(NoRng);
|
||||||
|
con.recv_bytes(b"SSH-2.0-OpenSSH_9.7\r\n").unwrap();
|
||||||
|
let msg = con.next_msg_to_send().unwrap();
|
||||||
|
assert!(matches!(msg.0, MsgKind::ServerProtocolInfo(_)));
|
||||||
|
}
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn protocol_exchange_slow_client() {
|
||||||
|
let mut con = ServerConnection::new(NoRng);
|
||||||
|
con.recv_bytes(b"SSH-2.0-").unwrap();
|
||||||
|
con.recv_bytes(b"OpenSSH_9.7\r\n").unwrap();
|
||||||
|
let msg = con.next_msg_to_send().unwrap();
|
||||||
|
assert!(matches!(msg.0, MsgKind::ServerProtocolInfo(_)));
|
||||||
|
}
|
||||||
|
|
||||||
|
#[test]
|
||||||
|
fn handshake() {
|
||||||
|
#[rustfmt::skip]
|
||||||
|
let rng = vec![
|
||||||
|
0x14, 0xa2, 0x04, 0xa5, 0x4b, 0x2f, 0x5f, 0xa7, 0xff, 0x53, 0x13, 0x67, 0x57, 0x67, 0xbc,
|
||||||
|
0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75, 0x95, 0x18, 0x4b, 0xd2, 0xcb, 0xd0,
|
||||||
|
0x64, 0x06, 0x14, 0xa2, 0x04, 0xa5, 0x4b, 0x2f, 0x5f, 0xa7, 0xff, 0x53, 0x13, 0x67, 0x57,
|
||||||
|
0x67, 0xbc, 0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75, 0x95, 0x18, 0x4b, 0xd2,
|
||||||
|
0xcb, 0xd0, 0x64, 0x06, 0x67, 0xbc, 0x55, 0x3f, 0xc0, 0x6c, 0x0d, 0x07, 0x8f, 0xe2, 0x75,
|
||||||
|
0x95, 0x18, 0x4b, 0xd2, 0xcb, 0xd0, 0x64, 0x06,
|
||||||
|
];
|
||||||
|
struct Part {
|
||||||
|
client: &'static [u8],
|
||||||
|
server: &'static [u8],
|
||||||
|
}
|
||||||
|
|
||||||
|
// Extracted from a real OpenSSH client using this server (with hardcoded creds) using Wireshark.
|
||||||
|
let conversation = [
|
||||||
|
Part {
|
||||||
|
client: &hex!("5353482d322e302d4f70656e5353485f392e370d0a"),
|
||||||
|
server: &hex!("5353482d322e302d4f70656e5353485f392e370d0a"),
|
||||||
|
},
|
||||||
|
// KEX Init
|
||||||
|
Part {
|
||||||
|
client: &hex!(
|
||||||
|
"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"
|
||||||
|
),
|
||||||
|
server: &hex!(
|
||||||
|
"000000bc051414a204a54b2f5fa7ff5313675767bc5500000011637572766532353531392d7368613235360000000b7373682d656432353531390000001d63686163686132302d706f6c7931333035406f70656e7373682e636f6d0000001d63686163686132302d706f6c7931333035406f70656e7373682e636f6d0000000d686d61632d736861322d3235360000000d686d61632d736861322d323536000000046e6f6e65000000046e6f6e65000000000000000000000000000000000000"
|
||||||
|
),
|
||||||
|
},
|
||||||
|
// ECDH KEX Init
|
||||||
|
Part {
|
||||||
|
client: &hex!(
|
||||||
|
"0000002c061e000000204c646d1281abf23264d63db96e05c0223cfead668d9d38c62579b8856e67ae19000000000000"
|
||||||
|
),
|
||||||
|
server: &hex!(
|
||||||
|
"000000bc081f000000330000000b7373682d6564323535313900000020e939cdfa6fc0d737333b534e913dd332c8d5179fe00c3045575217224b19b8f6000000204260e2c5e5383f1a021c9631fa61f60f305b29183fd219d4c8207c664e063410000000530000000b7373682d65643235353139000000406504a045499f26aa4ee17606ea6bd9e3f288838591f25d8604a63f77a52f5b9e909c00d10f386553e585d86ab329bbde0fca5c64b1b1982d7adcac17cf7f06010000000000000000"
|
||||||
|
),
|
||||||
|
},
|
||||||
|
// New Keys
|
||||||
|
Part {
|
||||||
|
client: &hex!("0000000c0a1500000000000000000000"),
|
||||||
|
server: &hex!("0000000c0a1500000000000000000000"),
|
||||||
|
},
|
||||||
|
// Service Request (encrypted)
|
||||||
|
Part {
|
||||||
|
client: &hex!("09ca4db7baeb24836a1f7d22368055bf4c26981ed86738ac7a5c31d0730ad656f1967853781dff91ee1c4de8"),
|
||||||
|
server: &hex!("7b444c0d5faf740d350701a054ea469fab1c98e4b669e4872a454163edb42ec5e4fa95c404ab601f016bd259"),
|
||||||
|
},
|
||||||
|
];
|
||||||
|
|
||||||
|
let mut con = ServerConnection::new(HardcodedRng(rng));
|
||||||
|
for part in conversation {
|
||||||
|
con.recv_bytes(&part.client).unwrap();
|
||||||
|
eprintln!("client: {:x?}", part.client);
|
||||||
|
let bytes = con.next_msg_to_send().unwrap().to_bytes();
|
||||||
|
if part.server != bytes {
|
||||||
|
panic!(
|
||||||
|
"expected != found\nexpected: {:x?}\nfound: {:x?}",
|
||||||
|
part.server, bytes
|
||||||
|
);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
6
ssh/Cargo.toml
Normal file
6
ssh/Cargo.toml
Normal file
|
|
@ -0,0 +1,6 @@
|
||||||
|
[package]
|
||||||
|
name = "ssh"
|
||||||
|
version = "0.1.0"
|
||||||
|
edition = "2021"
|
||||||
|
|
||||||
|
[dependencies]
|
||||||
3
ssh/README.md
Normal file
3
ssh/README.md
Normal file
|
|
@ -0,0 +1,3 @@
|
||||||
|
# ssh
|
||||||
|
|
||||||
|
`ssh(1)` SSH client.
|
||||||
3
ssh/src/main.rs
Normal file
3
ssh/src/main.rs
Normal file
|
|
@ -0,0 +1,3 @@
|
||||||
|
fn main() {
|
||||||
|
println!("Hello, world!");
|
||||||
|
}
|
||||||
Loading…
Add table
Add a link
Reference in a new issue