new: add pkh put, a native dput replacement for PPA uploads

Upload built source packages over SFTP with host-key verification
(Launchpad fingerprints pinned in host_keys.yml, ask-to-accept
otherwise), Launchpad account discovery (git config lp.user), and
pre-flight checks the upload queue itself never does: changes file
discovery/validation, PPA existence via the Launchpad API, target
series validity, and debian/control Section validity (sections
bundled in distro_info.yml). Upload log prevents duplicate uploads
unless --force.
This commit is contained in:
2026-09-16 21:38:53 +02:00
parent 9228ff448b
commit f27d27ea99
13 changed files with 2023 additions and 97 deletions
+611
View File
@@ -0,0 +1,611 @@
//! SSH/SFTP transport for uploads: SSH configuration lookup, connection
//! with host-key verification — Launchpad's published fingerprints are
//! pinned (no prompt on first use), other hosts fall back to
//! `~/.ssh/known_hosts` with an ask-to-accept for unknown keys —,
//! authentication (every ssh-agent identity first, then configured and
//! default key files) and chunked SFTP upload with progress reporting.
//!
//! This replaces dput-ng's paramiko transport with the `ssh2` (libssh2)
//! stack the rest of pkh already uses for build contexts.
use std::collections::HashMap;
use std::fs;
use std::io::{Read, Write};
use std::net::TcpStream;
use std::path::{Path, PathBuf};
use indicatif::ProgressBar;
use lazy_static::lazy_static;
use log::debug;
use serde::Deserialize;
use sha2::{Digest, Sha256};
use ssh2::{CheckResult, HostKeyType, KnownHostFileKind, Session};
use crate::ui::prompt;
const HOST_KEYS_YAML: &str = include_str!("../../host_keys.yml");
/// Pinned SSH host key fingerprints, loaded from the bundled
/// `host_keys.yml` data file (same pattern as `distro_info.yml`): data
/// rather than code, so trust anchors are updatable without touching the
/// source.
#[derive(Debug, Deserialize)]
struct PinnedHostKeys {
/// Host name → list of accepted `SHA256:<base64>` fingerprints; an
/// optional key type prefix (`ssh-rsa SHA256:...`) is tolerated.
fingerprints: HashMap<String, Vec<String>>,
}
lazy_static! {
// The YAML is include_str!'d at compile time and statically valid; if it
// ever failed to parse it would be a build-time bug that cannot be
// recovered from at runtime, so panicking here is acceptable.
static ref PINNED_HOST_KEYS: PinnedHostKeys = serde_yaml::from_str(HOST_KEYS_YAML)
.expect("built-in host_keys.yml data is statically valid and must parse");
}
/// Whether `fingerprint` is one of the pinned (published) fingerprints of
/// `host`, in which case the server is trusted without prompting
fn host_key_is_pinned(host: &str, fingerprint: &str) -> bool {
PINNED_HOST_KEYS.fingerprints.get(host).is_some_and(|pins| {
pins.iter()
.any(|pin| pin.split_whitespace().any(|token| token == fingerprint))
})
}
/// Per-host settings extracted from the SSH configuration files
/// (`/etc/ssh/ssh_config`, `~/.ssh/config`). Every option keeps the first
/// value obtained from the matching `Host` blocks, like OpenSSH.
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct SshConfig {
/// `HostName`: real host behind a configured alias.
pub host_name: Option<String>,
/// `User`: overrides the target's default login.
pub user: Option<String>,
/// `Port`: overrides the target's default port.
pub port: Option<u16>,
/// `IdentityFile`s to try for authentication, in declaration order.
pub identity_files: Vec<PathBuf>,
}
/// Look up `host` in the system and user SSH configuration files. Missing
/// files yield an empty configuration.
pub fn lookup_ssh_config(host: &str) -> SshConfig {
let mut config = SshConfig::default();
let mut files = vec![PathBuf::from("/etc/ssh/ssh_config")];
if let Some(home) = std::env::var_os("HOME") {
files.push(Path::new(&home).join(".ssh/config"));
}
for file in files {
if let Ok(content) = fs::read_to_string(&file) {
apply_config_file(&mut config, &content, host);
}
}
config
}
/// Fold one configuration file's matching `Host` blocks into `config`,
/// first obtained value wins per option.
fn apply_config_file(config: &mut SshConfig, content: &str, host: &str) {
let mut matching = false;
for line in content.lines() {
let line = line.trim();
if line.is_empty() || line.starts_with('#') {
continue;
}
let (keyword, rest) = match line.split_once(['=', ' ']) {
Some((k, r)) => (k.trim_end_matches('='), r.trim()),
None => (line, ""),
};
if keyword.eq_ignore_ascii_case("host") {
matching = rest
.split_whitespace()
.any(|pattern| match_pattern(host, pattern));
continue;
}
if !matching {
continue;
}
if keyword.eq_ignore_ascii_case("hostname") && config.host_name.is_none() {
config.host_name = Some(rest.to_string());
} else if keyword.eq_ignore_ascii_case("user") && config.user.is_none() {
config.user = Some(rest.to_string());
} else if keyword.eq_ignore_ascii_case("port") && config.port.is_none() {
if let Ok(port) = rest.parse() {
config.port = Some(port);
}
} else if keyword.eq_ignore_ascii_case("identityfile") {
let path = PathBuf::from(rest);
if !config.identity_files.contains(&path) {
config.identity_files.push(path);
}
}
}
}
/// One `Host` block pattern against a host name: exact match, `*` (any
/// run), `?` (one character) and `!pattern` negation (a matching negated
/// pattern excludes the host from the block).
fn match_pattern(host: &str, pattern: &str) -> bool {
if let Some(negated) = pattern.strip_prefix('!') {
!match_pattern(host, negated)
} else {
wildmatch(host, pattern)
}
}
/// `*`/`?` glob matching without allocation, enough for `Host` patterns
fn wildmatch(text: &str, pattern: &str) -> bool {
let text: Vec<char> = text.chars().collect();
let pattern: Vec<char> = pattern.chars().collect();
// Greedy backtracking over the pattern's last '*' position
let (mut t, mut p) = (0usize, 0usize);
let (mut star, mut mark) = (None::<usize>, 0usize);
while t < text.len() {
if p < pattern.len() && (pattern[p] == '?' || pattern[p] == text[t]) {
t += 1;
p += 1;
} else if p < pattern.len() && pattern[p] == '*' {
star = Some(p);
mark = t;
p += 1;
} else if let Some(s) = star {
p = s + 1;
mark += 1;
t = mark;
} else {
return false;
}
}
pattern[p..].iter().all(|&c| c == '*')
}
/// Connect to `host:port`, verify the server host key and authenticate as
/// `login`: every ssh-agent identity first, then the configured and default
/// identity files.
pub fn connect(
host: &str,
port: u16,
login: &str,
config: &SshConfig,
) -> Result<Session, Box<dyn std::error::Error>> {
let tcp = TcpStream::connect((host, port))
.map_err(|e| format!("cannot connect to {host}:{port}: {e}"))?;
let mut session = Session::new()?;
session.set_tcp_stream(tcp);
session
.handshake()
.map_err(|e| format!("SSH handshake with {host} failed: {e}"))?;
let (key, key_type) = session
.host_key()
.ok_or_else(|| format!("{host} offered no host key"))?;
verify_host_key(host, port, key, key_type)?;
authenticate(&session, host, login, config)?;
Ok(session)
}
/// Check the server's host key, in decreasing order of trust:
///
/// 1. matching one of the host's pinned (published, `host_keys.yml`)
/// fingerprints — accepted silently;
/// 2. matching `~/.ssh/known_hosts` — accepted;
/// 3. known-and-different — refused loudly (possible man-in-the-middle);
/// 4. unknown — fingerprint shown, explicit confirmation required, and on
/// acceptance the key is appended to the user's known hosts file
/// (dput's "ask to accept" policy).
fn verify_host_key(
host: &str,
port: u16,
key: &[u8],
key_type: HostKeyType,
) -> Result<(), Box<dyn std::error::Error>> {
let fingerprint = fingerprint(key);
if host_key_is_pinned(host, &fingerprint) {
debug!("{host} host key matches the published fingerprint");
return Ok(());
}
let mut known_hosts = Session::new()?.known_hosts()?;
for file in known_hosts_files() {
// Unreadable/unknown-format lines are skipped by libssh2; a missing
// file is fine
let _ = known_hosts.read_file(&file, KnownHostFileKind::OpenSSH);
}
let check = if port == 22 {
known_hosts.check(host, key)
} else {
known_hosts.check_port(host, port, key)
};
match check {
CheckResult::Match => Ok(()),
CheckResult::Mismatch => Err(format!(
"Host key verification failed for {host}: the server now presents a \
DIFFERENT key than the one recorded in your known_hosts files. \
This could be a man-in-the-middle attack, or the server was \
re-keyed. If you are sure it was re-keyed, remove the '{host}' \
line(s) from ~/.ssh/known_hosts and retry"
)
.into()),
CheckResult::NotFound | CheckResult::Failure => {
let key_type_desc = key_type_name(key_type).unwrap_or("Host");
let display = if port == 22 {
host.to_string()
} else {
format!("[{host}]:{port}")
};
// The banner is plain output: the confirmation prompt itself
// must stay a single line for its redraw logic
println!("The authenticity of host '{display}' can't be established.");
println!("{key_type_desc} key fingerprint is {fingerprint}.");
let accepted = prompt::confirm("Accept and store this host key?", false)?;
if !accepted {
return Err(format!("Host key for {display} rejected, aborting upload").into());
}
if let Some(name) = key_type_name(key_type) {
append_known_hosts_line(&format!("{display} {name} {}", base64_nopad(key)))?;
} else {
log::warn!("Unknown host key type: accepted for this session, not stored");
}
Ok(())
}
}
}
/// Known hosts files to consult, user file first (so that new keys are
/// accepted because of the user file, mirroring ssh's own ordering)
fn known_hosts_files() -> Vec<PathBuf> {
let mut files = Vec::new();
if let Some(home) = std::env::var_os("HOME") {
files.push(Path::new(&home).join(".ssh/known_hosts"));
}
files.push(PathBuf::from("/etc/ssh/ssh_known_hosts"));
files
}
/// Append one line to `~/.ssh/known_hosts` (creating the file), in the
/// plain OpenSSH `host keytype base64key` format
fn append_known_hosts_line(line: &str) -> Result<(), Box<dyn std::error::Error>> {
let Some(home) = std::env::var_os("HOME") else {
return Err("cannot record the host key: HOME is not set".into());
};
let path = Path::new(&home).join(".ssh/known_hosts");
fs::create_dir_all(path.parent().unwrap())?;
fs::OpenOptions::new()
.create(true)
.append(true)
.open(&path)?
.write_all(format!("{line}\n").as_bytes())
.map_err(|e| format!("cannot write to {}: {e}", path.display()))?;
debug!("Recorded host key line in {}", path.display());
Ok(())
}
/// Authenticate as `login`: every ssh-agent identity first (Launchpad
/// identifies uploaders by their registered key, which may be any entry of
/// the agent, not just the first), then identity files from the SSH
/// configuration and the usual `~/.ssh/id_*` defaults (passphrase-less
/// only — agent-loaded keys cover the protected ones).
fn authenticate(
session: &Session,
host: &str,
login: &str,
config: &SshConfig,
) -> Result<(), Box<dyn std::error::Error>> {
// Try every identity the agent offers, not just the first: the
// Launchpad-registered key is not necessarily the agent's default
let mut agent_identities: Option<usize> = None;
if let Ok(mut agent) = session.agent()
&& agent.connect().is_ok()
&& agent.list_identities().is_ok()
{
match agent.identities() {
Ok(identities) => {
let count = identities.len();
agent_identities = Some(count);
for identity in &identities {
if agent.userauth(login, identity).is_ok() && session.authenticated() {
debug!("authenticated through the ssh-agent");
return Ok(());
}
}
debug!("none of the {count} agent identity(ies) authenticated");
}
Err(e) => debug!("cannot list agent identities: {e}"),
}
}
let mut identity_files: Vec<PathBuf> = config.identity_files.clone();
if let Some(home) = std::env::var_os("HOME") {
for name in ["id_ed25519", "id_ecdsa", "id_rsa"] {
let key = Path::new(&home).join(".ssh").join(name);
if !identity_files.contains(&key) {
identity_files.push(key);
}
}
}
let mut tried = Vec::new();
for key in &identity_files {
if !key.is_file() {
continue;
}
match session.userauth_pubkey_file(login, None, key, None) {
Ok(()) => return Ok(()),
Err(e) => tried.push(format!("{} ({e})", key.display())),
}
}
if session.authenticated() {
return Ok(());
}
let agent_desc = match agent_identities {
Some(count) => format!("{count} ssh-agent identity(ies)"),
None => "no ssh-agent".to_string(),
};
Err(format!(
"SSH authentication failed for {login}@{host}: tried {agent_desc} \
and the identity files [{}]. Launchpad authenticates the '{login}' \
account with the SSH keys registered on it \
(https://launchpad.net/~/+editsshkeys): make sure such a key is \
available — load it with `ssh-add <key>` or point pkh at it with a \
'Host {host}' / 'IdentityFile' entry in ~/.ssh/config \
(passphrase-protected key files are only usable through the agent) \
— and check the account name with `git config lp.user`",
tried.join(", ")
)
.into())
}
/// Upload `local` to the remote SFTP `path`, updating `bar` per chunk. The
/// remote file is created/truncated; Launchpad's upload queue is
/// write-only, so failures here mean the upload failed — there is nothing
/// to inspect server-side.
pub fn upload_file(
sftp: &ssh2::Sftp,
local: &Path,
remote: &str,
bar: &ProgressBar,
) -> Result<(), Box<dyn std::error::Error>> {
let mut local_file =
fs::File::open(local).map_err(|e| format!("cannot open '{}': {}", local.display(), e))?;
let mut remote_file = sftp
.create(Path::new(remote))
.map_err(|e| format!("cannot create remote file {remote}: {e}"))?;
let mut buf = [0u8; 32 * 1024];
loop {
let n = local_file.read(&mut buf)?;
if n == 0 {
break;
}
remote_file
.write_all(&buf[..n])
.map_err(|e| format!("failed uploading to {remote}: {e}"))?;
bar.inc(n as u64);
}
Ok(())
}
/// Open the SFTP subsystem on `session`
pub fn sftp(session: &Session) -> Result<ssh2::Sftp, Box<dyn std::error::Error>> {
session
.sftp()
.map_err(|e| format!("cannot open the SFTP subsystem: {e}").into())
}
/// ssh-keygen-style `SHA256:<base64>` fingerprint of a raw host key
fn fingerprint(key: &[u8]) -> String {
let digest = Sha256::digest(key);
format!("SHA256:{}", base64_nopad(&digest))
}
/// OpenSSH name of a host key type, `None` when it cannot be named (and
/// thus not recorded in a known hosts file)
fn key_type_name(key_type: HostKeyType) -> Option<&'static str> {
match key_type {
HostKeyType::Rsa => Some("ssh-rsa"),
HostKeyType::Dss => Some("ssh-dss"),
HostKeyType::Ecdsa256 => Some("ecdsa-sha2-nistp256"),
HostKeyType::Ecdsa384 => Some("ecdsa-sha2-nistp384"),
HostKeyType::Ecdsa521 => Some("ecdsa-sha2-nistp521"),
HostKeyType::Ed25519 => Some("ssh-ed25519"),
HostKeyType::Unknown => None,
}
}
/// Standard-alphabet base64 without padding (the encoding used by SSH
/// fingerprints and known_hosts key fields)
fn base64_nopad(data: &[u8]) -> String {
const TABLE: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
let mut out = String::with_capacity(data.len().div_ceil(3) * 4);
for chunk in data.chunks(3) {
let b0 = chunk[0] as u32;
let b1 = chunk.get(1).copied().unwrap_or(0) as u32;
let b2 = chunk.get(2).copied().unwrap_or(0) as u32;
let n = (b0 << 16) | (b1 << 8) | b2;
out.push(TABLE[(n >> 18) as usize & 63] as char);
out.push(TABLE[(n >> 12) as usize & 63] as char);
if chunk.len() > 1 {
out.push(TABLE[(n >> 6) as usize & 63] as char);
}
if chunk.len() > 2 {
out.push(TABLE[n as usize & 63] as char);
}
}
out
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn base64_nopad_rfc4648_vectors() {
assert_eq!(base64_nopad(b""), "");
assert_eq!(base64_nopad(b"f"), "Zg");
assert_eq!(base64_nopad(b"fo"), "Zm8");
assert_eq!(base64_nopad(b"foo"), "Zm9v");
assert_eq!(base64_nopad(b"foob"), "Zm9vYg");
assert_eq!(base64_nopad(b"fooba"), "Zm9vYmE");
assert_eq!(base64_nopad(b"foobar"), "Zm9vYmFy");
}
/// The known_hosts encoding of a key matches what ssh-keyscan writes:
/// unpadded base64 of the raw wire-format key
#[test]
fn base64_nopad_matches_known_hosts_encoding() {
// echo -n hello | sha256sum →
let digest = Sha256::digest(b"hello");
assert_eq!(
fingerprint(b"hello"),
format!("SHA256:{}", base64_nopad(&digest))
);
// Verified with: printf 'hello' | sha256sum | xxd -r -p | base64 | tr -d '='
assert_eq!(
base64_nopad(&digest),
"LPJNul+wow4m6DsqxbninhsWHlwfp0JecwQzYpOLmCQ"
);
}
#[test]
fn wildmatch_handles_exact_and_wildcards() {
assert!(wildmatch("ppa.launchpad.net", "ppa.launchpad.net"));
assert!(wildmatch("ppa.launchpad.net", "*.launchpad.net"));
assert!(wildmatch("ppa.launchpad.net", "*"));
assert!(wildmatch("host1", "host?"));
assert!(!wildmatch("ppa.launchpad.net", "*.debian.org"));
assert!(!wildmatch("host12", "host?"));
}
/// Launchpad's published fingerprints (from the bundled host_keys.yml)
/// are pinned for its hosts, so the common upload never prompts. The
/// published entries carry an `ssh-rsa` key type prefix, which must not
/// prevent matching.
#[test]
fn launchpad_hosts_are_pinned() {
assert!(host_key_is_pinned(
"ppa.launchpad.net",
"SHA256:MGq+4hxD7RduVTcfwlwwboZnsgJC6SL/NltM8ye+gNg"
));
assert!(host_key_is_pinned(
"upload.ubuntu.com",
"SHA256:FN8sNU/MMmyvw/xtY5sAzkLGmkVQt2QpGZcwsHoBzjc"
));
// A different key is not pinned, even for a pinned host...
assert!(!host_key_is_pinned(
"ppa.launchpad.net",
"SHA256:totally-different-key-fingerprint"
));
// ...and other hosts have no pins: they fall back to known_hosts
// + prompt
assert!(!host_key_is_pinned(
"example.com",
"SHA256:MGq+4hxD7RduVTcfwlwwboZnsgJC6SL/NltM8ye+gNg"
));
}
#[test]
fn pattern_negation_excludes_host() {
assert!(!match_pattern("ppa.launchpad.net", "!*.launchpad.net"));
// A negated pattern only excludes; the other patterns of the block
// decide separately
assert!(match_pattern("example.com", "!*.launchpad.net example.com"));
assert!(!match_pattern(
"ppa.launchpad.net",
"example.com !*.launchpad.net"
));
}
#[test]
fn config_first_obtained_value_wins() {
// Like real configurations, the catch-all `Host *` block comes last:
// values from earlier matching blocks win, IdentityFile accumulates
let config = apply_config_file_all(
"\
Host ppa.launchpad.net
User myuser
IdentityFile ~/.ssh/lp_key
Host *
User fallback
ServerAliveInterval 30
IdentityFile ~/.ssh/other_key
",
"ppa.launchpad.net",
);
assert_eq!(config.user.as_deref(), Some("myuser"));
assert_eq!(
config.identity_files,
vec![
PathBuf::from("~/.ssh/lp_key"),
PathBuf::from("~/.ssh/other_key")
]
);
assert_eq!(config.host_name, None);
assert_eq!(config.port, None);
}
#[test]
fn config_wildcard_and_question_marks_match() {
let config = apply_config_file_all(
"\
Host *.launchpad.net
HostName launchpad-real.example.com
Port 2222
",
"ppa.launchpad.net",
);
assert_eq!(
config.host_name.as_deref(),
Some("launchpad-real.example.com")
);
assert_eq!(config.port, Some(2222));
}
#[test]
fn config_ignores_unrelated_blocks_and_comments() {
let config = apply_config_file_all(
"\
# a comment
Host github.com
User git
Host other
User nope
",
"ppa.launchpad.net",
);
assert_eq!(config, SshConfig::default());
}
/// Parse helper for tests: applies `content` for `host` to a fresh config
fn apply_config_file_all(content: &str, host: &str) -> SshConfig {
let mut config = SshConfig::default();
apply_config_file(&mut config, content, host);
config
}
}