Adding upstream version 0.5.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

build/openssh.rs

@@ -0,0 +1,88 @@
+use std::path::{Path, PathBuf};
+
+use crate::define_parser::parse_defines;
+
+const OPENSSH_TAG: &str = "V_9_9_P2";
+
+/// Default algorithms for ssh.
+#[derive(Debug, Default, Clone, PartialEq, Eq)]
+pub struct MyPrefs {
+    pub ca_signature_algorithms: Vec<String>,
+    pub ciphers: Vec<String>,
+    pub host_key_algorithms: Vec<String>,
+    pub kex_algorithms: Vec<String>,
+    pub mac: Vec<String>,
+    pub pubkey_accepted_algorithms: Vec<String>,
+}
+
+pub fn get_my_prefs() -> anyhow::Result<MyPrefs> {
+    let out_dir = std::env::var_os("OUT_DIR")
+        .map(|s| PathBuf::from(s).join("openssh"))
+        .ok_or_else(|| anyhow::anyhow!("OUT_DIR not set"))?;
+    let build_dir = out_dir.join("build");
+    let inner_dir = build_dir.join("src");
+
+    std::fs::remove_dir_all(&build_dir).ok();
+    std::fs::create_dir_all(&inner_dir).ok();
+
+    clone_openssh(&inner_dir)?;
+
+    let my_proposal_path = inner_dir.join("myproposal.h");
+
+    let reader = std::io::BufReader::new(std::fs::File::open(my_proposal_path)?);
+    let defines = parse_defines(reader)?;
+
+    let ca_signature_algorithms = defines
+        .get("SSH_ALLOWED_CA_SIGALGS")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    let ciphers = defines
+        .get("KEX_CLIENT_ENCRYPT")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    let host_key_algorithms = defines
+        .get("KEX_DEFAULT_PK_ALG")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    let kex_algorithms = defines
+        .get("KEX_CLIENT")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    let mac = defines
+        .get("KEX_CLIENT_MAC")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    let pubkey_accepted_algorithms = defines
+        .get("KEX_DEFAULT_PK_ALG")
+        .map(|s| s.split_whitespace().map(|s| format!(r#""{s}""#)).collect())
+        .unwrap_or_default();
+
+    Ok(MyPrefs {
+        ca_signature_algorithms,
+        ciphers,
+        host_key_algorithms,
+        kex_algorithms,
+        mac,
+        pubkey_accepted_algorithms,
+    })
+}
+
+fn clone_openssh(path: &Path) -> anyhow::Result<()> {
+    let repo_url = "https://github.com/openssh/openssh-portable.git";
+    let repo = git2::Repository::clone(repo_url, path)?;
+
+    let obj = repo.revparse_single(OPENSSH_TAG)?;
+
+    let commit = obj.peel_to_commit()?;
+
+    repo.checkout_tree(&obj, None)?;
+
+    repo.set_head_detached(commit.id())?;
+
+    Ok(())
+}