fluidattacks_core_git/clone/
https.rs

1use anyhow::{Context, Result};
2use base64::Engine;
3use http::uri::{PathAndQuery, Uri};
4use std::fmt;
5use std::path::Path;
6use tokio::process::Command;
7use url::Url;
8
9use super::{build_clone_args, reason, redirect_config, CloneOpts};
10use crate::errors::{GitCallError, HttpsAccessError};
11use crate::types::CredentialKind;
12
13const USER_VAR: &str = "FLUIDATTACKS_GIT_USER";
14const PASSWORD_VAR: &str = "FLUIDATTACKS_GIT_PASSWORD";
15
16// Answers only `get`, so git has nowhere to store or erase the credential.
17fn env_helper() -> String {
18    format!(
19        "!f() {{ if [ \"$1\" = get ]; then \
20         printf 'username=%s\\npassword=%s\\n' \"${USER_VAR}\" \"${PASSWORD_VAR}\"; fi; }}; f"
21    )
22}
23
24// Read as git and curl read it (RFC 3986), host and path left as written: git
25// normalizes the url and the helper key alike when it matches one to the other.
26struct BareUrl {
27    url: String,
28    origin: String,
29}
30
31/// How git reaches a repo over https, with the credential kept off its command
32/// line and out of the url, so that git has none of it to print back.
33///
34/// `git` hands the credential to the repo's own host and to no other, and
35/// never lets git prompt. `secret` is what is still worth taking out of an
36/// error, because a server may echo what it was sent.
37pub struct HttpsAccess {
38    url: String,
39    secret: Option<String>,
40    config: Vec<(String, String)>,
41    env: Vec<(String, String)>,
42}
43
44// By hand, so that printing it, in a log or a failed unwrap, leaves the login out.
45impl fmt::Debug for HttpsAccess {
46    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
47        f.debug_struct("HttpsAccess")
48            .field("url", &self.url)
49            .finish_non_exhaustive()
50    }
51}
52
53impl HttpsAccess {
54    pub fn new(url: &str, credential: Option<&CredentialKind>) -> Result<Self, HttpsAccessError> {
55        match credential {
56            None => Ok(Self::public(url)),
57            Some(CredentialKind::Https { user, password }) => Self::basic(url, user, password),
58            Some(CredentialKind::Token {
59                token,
60                is_pat,
61                oauth_type,
62            }) => {
63                let (user, password) = token_login(token, oauth_type, *is_pat);
64                Ok(Self {
65                    secret: Some(token.clone()),
66                    ..Self::basic(url, user, password)?
67                })
68            }
69            Some(CredentialKind::Ssh { .. } | CredentialKind::AwsRole { .. }) => {
70                Err(HttpsAccessError::NotHttpsCredential)
71            }
72        }
73    }
74
75    fn public(url: &str) -> Self {
76        Self {
77            url: url.to_owned(),
78            secret: None,
79            config: Vec::new(),
80            env: Vec::new(),
81        }
82    }
83
84    fn basic(raw_url: &str, user: &str, password: &str) -> Result<Self, HttpsAccessError> {
85        if [user, password]
86            .iter()
87            .any(|value| value.contains(['\n', '\r', '\0']))
88        {
89            return Err(HttpsAccessError::CredentialLineBreak);
90        }
91        let url = bare_url(raw_url)?;
92        Ok(Self {
93            secret: Some(password.to_owned()),
94            config: vec![(format!("credential.{}.helper", url.origin), env_helper())],
95            env: vec![
96                (USER_VAR.to_owned(), user.to_owned()),
97                (PASSWORD_VAR.to_owned(), password.to_owned()),
98            ],
99            url: url.url,
100        })
101    }
102
103    #[must_use]
104    pub fn url(&self) -> &str {
105        &self.url
106    }
107
108    /// A git command for this repo, still waiting for its subcommand.
109    #[must_use]
110    pub fn git(&self) -> Command {
111        let mut command = Command::new("git");
112        // The empty helper drops whatever helpers the machine has configured,
113        // so the credential is neither looked up in nor saved to them. Going
114        // on the command line, it comes after any config git inherits.
115        command.args(["-c", "credential.helper="]);
116        for (key, value) in &self.config {
117            command.arg("-c").arg(format!("{key}={value}"));
118        }
119        command
120            .env("GIT_TERMINAL_PROMPT", "0")
121            // Unset, git keeps credentials out of its own traces.
122            .env_remove("GIT_TRACE_REDACT")
123            // Its data dump prints what a server sends back, the Basic header included.
124            .env_remove("GIT_TRACE_CURL")
125            .envs(self.env.iter().cloned());
126        command
127    }
128
129    #[must_use]
130    pub fn secret(&self) -> Option<&str> {
131        self.secret.as_deref()
132    }
133}
134
135fn bare_url(raw_url: &str) -> Result<BareUrl, HttpsAccessError> {
136    let uri: Uri = raw_url.parse().map_err(|_| HttpsAccessError::Unparsable)?;
137    let scheme = uri
138        .scheme_str()
139        .filter(|scheme| matches!(*scheme, "http" | "https"))
140        .ok_or(HttpsAccessError::NotHttp)?;
141    let authority = uri.authority().ok_or(HttpsAccessError::Unparsable)?;
142    let port = authority
143        .port()
144        .map_or_else(String::new, |port| format!(":{port}"));
145    let host = format!("{}{port}", authority.host());
146    // An empty host, or a port the parser could not read and left out.
147    if authority.host().is_empty() || !authority.as_str().ends_with(&host) {
148        return Err(HttpsAccessError::Unparsable);
149    }
150    let origin = format!("{scheme}://{host}");
151    let path = uri.path_and_query().map_or("", PathAndQuery::as_str);
152    Ok(BareUrl {
153        url: format!("{origin}{path}"),
154        origin,
155    })
156}
157
158// A token with no provider is the user itself, with no password. A PAT takes
159// any user but an empty one, since git sends no credential without a user.
160const fn token_login<'a>(token: &'a str, provider: &str, is_pat: bool) -> (&'a str, &'a str) {
161    if is_pat {
162        ("pat", token)
163    } else if provider.eq_ignore_ascii_case("BITBUCKET") {
164        ("x-token-auth", token)
165    } else if provider.is_empty() {
166        (token, "")
167    } else {
168        ("oauth2", token)
169    }
170}
171
172pub async fn clone_https(opts: &CloneOpts, dest: &Path) -> Result<()> {
173    let kind = &opts
174        .credentials
175        .as_ref()
176        .context("missing credentials")?
177        .kind;
178    if !matches!(kind, CredentialKind::Https { .. }) {
179        anyhow::bail!("expected HTTPS credentials");
180    }
181    Ok(run_git_clone(opts, dest, &HttpsAccess::new(&opts.repo_url, Some(kind))?).await?)
182}
183
184pub async fn clone_https_token(opts: &CloneOpts, dest: &Path) -> Result<()> {
185    let kind = &opts
186        .credentials
187        .as_ref()
188        .context("missing credentials")?
189        .kind;
190    if !matches!(kind, CredentialKind::Token { .. }) {
191        anyhow::bail!("expected Token credentials");
192    }
193    Ok(run_git_clone(opts, dest, &HttpsAccess::new(&opts.repo_url, Some(kind))?).await?)
194}
195
196pub async fn clone_https_public(opts: &CloneOpts, dest: &Path) -> Result<()> {
197    Ok(run_git_clone(opts, dest, &HttpsAccess::public(&opts.repo_url)).await?)
198}
199
200#[must_use]
201pub fn build_https_config_args(
202    follow_redirects: bool,
203    is_pat: bool,
204    token: Option<&str>,
205    disable_credential_prompt: bool,
206) -> Vec<String> {
207    let mut args = vec![
208        "-c".to_owned(),
209        "http.sslVerify=false".to_owned(),
210        "-c".to_owned(),
211        format!("http.followRedirects={follow_redirects}"),
212    ];
213    if is_pat {
214        if let Some(t) = token {
215            let encoded = base64::engine::general_purpose::STANDARD.encode(format!(":{t}"));
216            args.extend([
217                "-c".to_owned(),
218                format!("http.extraHeader=Authorization: Basic {encoded}"),
219            ]);
220        }
221    }
222    if disable_credential_prompt {
223        args.extend(["-c".to_owned(), "credential.helper=".to_owned()]);
224    }
225    args
226}
227
228#[allow(clippy::too_many_arguments)]
229pub fn format_https_url(
230    repo_url: &str,
231    user: Option<&str>,
232    password: Option<&str>,
233    token: Option<&str>,
234    provider: Option<&str>,
235    is_pat: bool,
236) -> Result<String> {
237    let mut parsed = Url::parse(repo_url).context("parsing URL")?;
238    // Re-quote the path
239    let path = parsed.path().to_owned();
240    parsed.set_path(&path);
241
242    if is_pat {
243        return Ok(parsed.to_string());
244    }
245
246    if let Some(t) = token {
247        let user_part = match provider {
248            Some(p) if p.eq_ignore_ascii_case("BITBUCKET") => "x-token-auth",
249            Some("") | None => "",
250            Some(_) => "oauth2",
251        };
252        if user_part.is_empty() {
253            // No provider: use token as username, no password
254            parsed
255                .set_username(t)
256                .map_err(|()| anyhow::anyhow!("set username"))?;
257            parsed
258                .set_password(None)
259                .map_err(|()| anyhow::anyhow!("set password"))?;
260        } else {
261            // Use username/password separately to avoid percent-encoding the colon
262            parsed
263                .set_username(user_part)
264                .map_err(|()| anyhow::anyhow!("set username"))?;
265            parsed
266                .set_password(Some(t))
267                .map_err(|()| anyhow::anyhow!("set password"))?;
268        }
269        return Ok(parsed.to_string());
270    }
271
272    if let (Some(u), Some(p)) = (user, password) {
273        parsed
274            .set_username(u)
275            .map_err(|()| anyhow::anyhow!("set username"))?;
276        parsed
277            .set_password(Some(p))
278            .map_err(|()| anyhow::anyhow!("set password"))?;
279        return Ok(parsed.to_string());
280    }
281
282    Ok(parsed.to_string())
283}
284
285pub(super) async fn run_git_clone(
286    opts: &CloneOpts,
287    dest: &Path,
288    access: &HttpsAccess,
289) -> Result<(), GitCallError> {
290    let mut command = access.git();
291    command.args(clone_args(opts, dest, access));
292    reason::run(&mut command, access.secret().as_slice()).await
293}
294
295fn clone_args(opts: &CloneOpts, dest: &Path, access: &HttpsAccess) -> Vec<std::ffi::OsString> {
296    let mut extra_config = vec!["-c".to_owned(), "http.sslVerify=false".to_owned()];
297    extra_config.extend(redirect_config(opts.follow_redirects));
298    build_clone_args(opts, access.url(), dest, &extra_config)
299}
300
301#[cfg(test)]
302mod tests {
303    use super::{clone_args, format_https_url, token_login, HttpsAccess};
304    use crate::clone::tests::opts;
305    use crate::clone::{CloneOpts, CloneShape};
306    use crate::errors::HttpsAccessError;
307    use crate::types::CredentialKind;
308    use std::ffi::OsString;
309
310    fn args(access: &HttpsAccess) -> Vec<String> {
311        access
312            .git()
313            .as_std()
314            .get_args()
315            .map(|arg| arg.to_string_lossy().into_owned())
316            .collect()
317    }
318
319    fn token(token: &str, provider: &str) -> CredentialKind {
320        CredentialKind::Token {
321            token: token.to_owned(),
322            is_pat: false,
323            oauth_type: provider.to_owned(),
324        }
325    }
326
327    #[test]
328    fn a_token_with_no_provider_logs_in_as_the_user_with_no_password() {
329        assert_eq!(token_login("tok", "", false), ("tok", ""));
330    }
331
332    #[test]
333    fn the_provider_names_the_user_even_off_its_own_domain() {
334        assert_eq!(
335            token_login("tok", "BITBUCKET", false),
336            ("x-token-auth", "tok")
337        );
338        assert_eq!(token_login("tok", "GITLAB", false), ("oauth2", "tok"));
339    }
340
341    #[test]
342    fn the_provider_is_matched_ignoring_the_case() {
343        let url = "https://host/a/b.git";
344
345        assert_eq!(
346            format_https_url(url, None, None, Some("tok"), Some("Bitbucket"), false).unwrap(),
347            format_https_url(url, None, None, Some("tok"), Some("BITBUCKET"), false).unwrap()
348        );
349        assert_eq!(
350            token_login("tok", "Bitbucket", false),
351            token_login("tok", "BITBUCKET", false)
352        );
353    }
354
355    fn basic(user: &str, password: &str) -> CredentialKind {
356        CredentialKind::Https {
357            user: user.to_owned(),
358            password: password.to_owned(),
359        }
360    }
361
362    #[test]
363    fn the_url_drops_whatever_credential_it_carried() {
364        let access = HttpsAccess::new(
365            "https://olduser:oldpass@host/a/b.git",
366            Some(&token("tok", "")),
367        )
368        .unwrap();
369        assert_eq!(access.url(), "https://host/a/b.git");
370    }
371
372    #[test]
373    fn a_pat_logs_in_as_a_placeholder_user_whatever_the_provider() {
374        assert_eq!(token_login("tok", "", true), ("pat", "tok"));
375        assert_eq!(token_login("tok", "BITBUCKET", true), ("pat", "tok"));
376    }
377
378    #[test]
379    fn the_host_is_left_as_written_for_git_to_read() {
380        for (url, expected) in [
381            ("https://Host:443/a.git", "https://Host:443/a.git"),
382            ("https://[::1]:8443/a.git", "https://[::1]:8443/a.git"),
383            ("https://u:p@w@host/a.git", "https://host/a.git"),
384        ] {
385            let access = HttpsAccess::new(url, Some(&token("tok", ""))).unwrap();
386            let origin = expected.trim_end_matches("/a.git");
387            assert_eq!(access.url(), expected, "{url}");
388            let helper = format!("credential.{origin}.helper=");
389            let host = args(&access).get(3).cloned().unwrap_or_default();
390            assert!(host.starts_with(&helper), "{url}");
391        }
392    }
393
394    #[test]
395    fn each_failure_says_what_the_python_said_and_never_the_url() {
396        for (url, expected) in [
397            ("ftp://u:hunter2@host/a.git", HttpsAccessError::NotHttp),
398            ("host/a.git", HttpsAccessError::Unparsable),
399            ("https:u:hunter2@host/a.git", HttpsAccessError::Unparsable),
400            ("https:///host/a.git", HttpsAccessError::Unparsable),
401            ("https://u:hunter2@/a.git", HttpsAccessError::Unparsable),
402            ("https://u:hunter2@:443/a.git", HttpsAccessError::Unparsable),
403            (
404                "https://u:hunter2@host:99999/a.git",
405                HttpsAccessError::Unparsable,
406            ),
407            (
408                "https://u:hunter2@faß.de/a.git",
409                HttpsAccessError::Unparsable,
410            ),
411            (
412                "https://tok\\hunter2@host/a.git",
413                HttpsAccessError::Unparsable,
414            ),
415        ] {
416            let error = HttpsAccess::new(url, Some(&token("tok", ""))).unwrap_err();
417            assert_eq!(error, expected, "{url}");
418            assert!(!error.to_string().contains("hunter2"), "{url}");
419        }
420        assert_eq!(
421            HttpsAccessError::NotHttp.to_string(),
422            "expected an http or https url"
423        );
424        assert_eq!(
425            HttpsAccessError::Unparsable.to_string(),
426            "Invalid url: its host or port could not be parsed"
427        );
428    }
429
430    #[test]
431    fn no_credential_leaves_the_url_unchecked() {
432        let access = HttpsAccess::new("ftp://host:99999/a.git", None).unwrap();
433        assert_eq!(access.url(), "ftp://host:99999/a.git");
434        assert_eq!(args(&access), ["-c", "credential.helper="]);
435    }
436
437    #[test]
438    fn the_debug_shows_neither_the_login_nor_the_environment() {
439        let access =
440            HttpsAccess::new("https://host/a.git", Some(&basic("someone", "s3cr3t"))).unwrap();
441        let shown = format!("{access:?}");
442        assert!(shown.contains("https://host/a.git"), "{shown}");
443        assert!(!shown.contains("s3cr3t"), "{shown}");
444        assert!(!shown.contains("someone"), "{shown}");
445    }
446
447    #[test]
448    fn the_machine_helpers_are_dropped_before_the_host_helper() {
449        let access = HttpsAccess::new("https://host/a.git", Some(&token("tok", ""))).unwrap();
450        let args = args(&access);
451        let [flag, machine, host_flag, host] = args.as_slice() else {
452            panic!("{args:?}");
453        };
454        assert_eq!(
455            [flag, machine, host_flag],
456            ["-c", "credential.helper=", "-c"]
457        );
458        assert!(
459            host.starts_with("credential.https://host.helper=!f()"),
460            "{host}"
461        );
462    }
463
464    #[test]
465    fn the_login_goes_through_the_environment() {
466        let access = HttpsAccess::new("https://host/a.git", Some(&basic("u", "p"))).unwrap();
467        let envs: Vec<_> = access
468            .git()
469            .as_std()
470            .get_envs()
471            .map(|(name, value)| (name.to_owned(), value.map(ToOwned::to_owned)))
472            .collect();
473        let set = |value: &str| Some(OsString::from(value));
474        assert_eq!(
475            envs,
476            [
477                ("FLUIDATTACKS_GIT_PASSWORD".into(), set("p")),
478                ("FLUIDATTACKS_GIT_USER".into(), set("u")),
479                ("GIT_TERMINAL_PROMPT".into(), set("0")),
480                ("GIT_TRACE_CURL".into(), None),
481                ("GIT_TRACE_REDACT".into(), None),
482            ]
483        );
484    }
485
486    #[test]
487    fn a_credential_with_a_line_break_or_a_nul_is_refused() {
488        for credential in [
489            token("tok\nhost=x", ""),
490            token("tok\0x", "GITLAB"),
491            basic("u\rx", "p"),
492            basic("u", "p\nx"),
493        ] {
494            let error = HttpsAccess::new("https://host/a/b.git", Some(&credential)).unwrap_err();
495            assert_eq!(error, HttpsAccessError::CredentialLineBreak);
496            assert_eq!(
497                error.to_string(),
498                "Invalid credentials: a line break or a nul byte"
499            );
500        }
501    }
502
503    #[test]
504    fn an_empty_provider_formats_the_url_like_no_provider_at_all() {
505        let url = "https://gitlab.com/a/b.git";
506        let no_provider = format_https_url(url, None, None, Some("tok"), None, false).unwrap();
507        assert_eq!(no_provider, "https://tok@gitlab.com/a/b.git");
508        assert_eq!(
509            format_https_url(url, None, None, Some("tok"), Some(""), false).unwrap(),
510            no_provider
511        );
512    }
513
514    #[test]
515    fn a_redirect_is_followed_only_when_the_root_asks_for_one() {
516        for follow_redirects in [false, true] {
517            let opts = CloneOpts {
518                follow_redirects,
519                ..opts(CloneShape::SingleBranch)
520            };
521            let access = HttpsAccess::new(&opts.repo_url, None).unwrap();
522
523            let args = clone_args(&opts, std::path::Path::new("/tmp/a_root"), &access);
524
525            let config = format!("http.followRedirects={follow_redirects}");
526            assert!(args.windows(2).any(|pair| pair == ["-c", config.as_str()]));
527        }
528    }
529}
fluidattacks_core_git/clone/https.rs

fluidattacks_core_git/clone/
https.rs
