michal/tit
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Blob: tests/public_routes.rs
#[allow(
dead_code,
reason = "the public-route test does not use account mutations"
)]
#[path = "../src/account.rs"]
mod account;
#[allow(
dead_code,
reason = "the public-route test uses only username validation"
)]
#[path = "../src/auth.rs"]
mod auth;
#[path = "../src/domain/mod.rs"]
mod domain;
#[path = "../src/feed.rs"]
mod feed;
#[allow(
dead_code,
reason = "the public-route test does not use each shared Git API"
)]
#[path = "../src/git/mod.rs"]
mod git;
#[allow(
dead_code,
reason = "the public-route test uses the public Web server only"
)]
#[path = "../src/http/mod.rs"]
mod http;
#[allow(
dead_code,
reason = "the public-route test creates instance files directly"
)]
#[path = "../src/instance.rs"]
mod instance;
#[path = "../src/markdown.rs"]
mod markdown;
#[allow(dead_code, reason = "the public-route test uses anonymous policy only")]
#[path = "../src/policy.rs"]
mod policy;
#[allow(
dead_code,
reason = "the public route test does not create repositories through forms"
)]
#[path = "../src/repository.rs"]
mod repository;
#[allow(dead_code, reason = "the public-route test does not complete a login")]
#[path = "../src/session.rs"]
mod session;
#[allow(
dead_code,
reason = "the public-route test does not use each store API"
)]
#[path = "../src/store/mod.rs"]
mod store;
use std::collections::BTreeMap;
use std::fs;
use std::io::{Read, Write};
use std::net::{Ipv4Addr, SocketAddr, TcpStream};
use std::path::Path;
use std::process::Command;
use http::{PublicWebConfig, RunningWebServer};
use store::{InitialAdministrator, NewRepository, RepositoryOrigin, Store};
use tempfile::TempDir;
#[tokio::test(flavor = "multi_thread", worker_threads = 4)]
async fn browses_and_clones_public_repositories_for_both_hash_formats() {
for format in ["sha1", "sha256"] {
let fixture = Fixture::new(format);
let server = RunningWebServer::start_public(
SocketAddr::from((Ipv4Addr::LOCALHOST, 0)),
PublicWebConfig {
instance_dir: fixture.instance.path().to_owned(),
http_clone_base: "https://tit.example".to_owned(),
ssh_clone_base: "ssh://tit.example:2222".to_owned(),
},
)
.await
.expect("start the public Web server");
let summary = request(server.address(), "GET", "/alice/example", &[], &[]);
assert_eq!(summary.status, 200);
assert_html_policy(&summary);
let summary_text = summary.text();
assert!(summary_text.contains("<h1><a href=\"/alice/example\">alice/example</a></h1>"));
assert!(summary_text.contains("https://tit.example/alice/example"));
assert!(summary_text.contains("ssh://tit.example:2222/alice/example"));
assert!(summary_text.contains(&fixture.head));
assert!(summary_text.contains("README.md"));
assert!(summary_text.contains("<h1>tit fixture</h1>"));
assert!(summary_text.contains("<strong>safe</strong>"));
assert!(summary_text.contains("<code><safe></code>"));
assert!(summary_text.contains("href=\"docs/guide.md\""));
assert!(!summary_text.contains("<script"));
assert!(!summary_text.contains("javascript:"));
assert!(!summary_text.contains("<img"));
assert!(!summary_text.contains("tracker.example"));
assert!(summary_text.contains("<script>alert(3)</script>"));
assert!(summary_text.contains("/alice/example/atom.xml"));
assert!(summary_text.contains("/alice/example/rss.xml"));
assert!(summary_text.contains("/alice/example/search"));
let mut feed_entry_ids = Vec::new();
for (path, content_type) in [
(
"/alice/example/atom.xml",
"application/atom+xml; charset=utf-8",
),
(
"/alice/example/rss.xml",
"application/rss+xml; charset=utf-8",
),
] {
let feed = request(server.address(), "GET", path, &[], &[]);
assert_eq!(feed.status, 200);
assert_eq!(feed.header("content-type"), content_type);
assert_eq!(feed.header("cache-control"), "public, max-age=60");
assert!(!feed.header("etag").is_empty());
assert!(!feed.header("last-modified").is_empty());
let parsed = feed_rs::parser::parse(feed.body.as_slice()).expect("parse the feed");
assert_eq!(parsed.entries.len(), 1);
assert!(parsed.entries[0].id.starts_with("urn:tit:event:"));
feed_entry_ids.push(parsed.entries[0].id.clone());
assert!(feed.text().contains("Repository imported"));
let etag = feed.header("etag");
let conditional = request(
server.address(),
"GET",
path,
&[("If-None-Match", etag)],
&[],
);
assert_eq!(conditional.status, 304);
assert!(conditional.body.is_empty());
let modified = request(
server.address(),
"GET",
path,
&[("If-Modified-Since", feed.header("last-modified"))],
&[],
);
assert_eq!(modified.status, 304);
assert!(modified.body.is_empty());
let head = request(server.address(), "HEAD", path, &[], &[]);
assert_eq!(head.status, 200);
assert!(head.body.is_empty());
assert_eq!(head.header("etag"), feed.header("etag"));
}
assert_eq!(feed_entry_ids[0], feed_entry_ids[1]);
let invalid_page = request(
server.address(),
"GET",
"/alice/example/atom.xml?before=0",
&[],
&[],
);
assert_eq!(invalid_page.status, 400);
let database = fixture.instance.path().join("tit.sqlite3");
let feed_store = Store::open(&database).expect("open the feed database");
for timestamp in 10..35 {
let actor = if timestamp == 34 {
"x</title><script>alert(5)</script>"
} else {
"alice"
};
feed_store
.connection()
.execute(
"INSERT INTO repository_event
(event_id, repository_id, sequence, kind, actor, payload_version,
payload, created_at)
VALUES (
lower(hex(randomblob(16))),
?1,
(SELECT COALESCE(MAX(sequence), 0) + 1
FROM repository_event WHERE repository_id = ?1),
'push', ?2, 1, '{\"version\":1}', ?3
)",
rusqlite::params![fixture.repository_id, actor, timestamp],
)
.expect("insert a page fixture event");
}
drop(feed_store);
let first_page = request(server.address(), "GET", "/alice/example/atom.xml", &[], &[]);
let first_feed =
feed_rs::parser::parse(first_page.body.as_slice()).expect("parse the first page");
assert_eq!(first_feed.entries.len(), 20);
assert!(!first_page.text().contains("<script>"));
assert!(first_page.text().contains("x</title><script>"));
let next = first_page
.text()
.split("rel=\"next\" href=\"")
.nth(1)
.and_then(|value| value.split('\"').next())
.expect("find the next-page URL")
.replace("https://tit.example", "");
let second_page = request(server.address(), "GET", &next, &[], &[]);
let second_feed =
feed_rs::parser::parse(second_page.body.as_slice()).expect("parse the second page");
assert_eq!(second_feed.entries.len(), 6);
assert!(!second_page.text().contains("rel=\"next\""));
let empty = request(server.address(), "GET", "/alice/empty", &[], &[]);
assert_eq!(empty.status, 200);
assert!(empty.text().contains("This repository has no commits."));
let empty_search = request(server.address(), "GET", "/alice/empty/search", &[], &[]);
assert_eq!(empty_search.status, 200);
assert!(
empty_search
.text()
.contains("This repository has no commits to search.")
);
let alias = request(server.address(), "GET", "/alice/example.git", &[], &[]);
assert_eq!(alias.status, 308);
assert_eq!(alias.header("location"), "/alice/example");
let routes = [
"/alice/example/refs".to_owned(),
"/alice/example/search".to_owned(),
format!("/alice/example/commit/{}", fixture.head),
format!("/alice/example/tree/{}", fixture.head),
format!("/alice/example/tree/{}/nested", fixture.head),
format!("/alice/example/blob/{}/nested/file.txt", fixture.head),
format!("/alice/example/diff/{}/{}", fixture.parent, fixture.head),
format!("/alice/example/blame/{}/nested/file.txt", fixture.head),
];
for route in &routes {
let response = request(server.address(), "GET", route, &[], &[]);
assert_eq!(response.status, 200, "route failed: {route}");
assert_html_policy(&response);
assert!(!response.text().to_ascii_lowercase().contains("<script"));
let head = request(server.address(), "HEAD", route, &[], &[]);
assert_eq!(head.status, 200, "HEAD failed: {route}");
assert!(head.body.is_empty());
assert_eq!(
head.header("content-length"),
response.body.len().to_string()
);
}
let search = request(
server.address(),
"GET",
"/alice/example/search?q=second%20line&ref=HEAD",
&[],
&[],
);
assert_eq!(search.status, 200);
assert_html_policy(&search);
let search_text = search.text();
assert!(search_text.contains("Found 1 matching lines."));
assert!(search_text.contains("nested/file.txt:2"));
assert!(search_text.contains(&format!(
"/alice/example/blob/{}/nested/file.txt",
fixture.head
)));
assert!(search_text.contains("<option value=\"HEAD\" selected>HEAD</option>"));
let malformed = request(
server.address(),
"GET",
"/alice/example/search?q=needle&ref=refs%2Fheads%2Fmain",
&[],
&[],
);
assert_eq!(malformed.status, 200);
assert!(malformed.text().contains("malformed.txt:1"));
assert!(malformed.text().contains("start � needle"));
let escaped = request(
server.address(),
"GET",
"/alice/example/search?q=%3Cscript%3E&ref=HEAD",
&[],
&[],
);
assert_eq!(escaped.status, 200);
assert!(!escaped.text().contains("value=\"<script>\""));
assert!(escaped.text().contains("value=\"<script>\""));
assert_eq!(
request(
server.address(),
"GET",
"/alice/example/search?q=&ref=HEAD",
&[],
&[],
)
.status,
400
);
assert_eq!(
request(
server.address(),
"GET",
"/alice/example/search?q=text&ref=refs%2Fheads%2Fmissing",
&[],
&[],
)
.status,
404
);
let tree = request(
server.address(),
"GET",
&format!("/alice/example/tree/{}", fixture.head),
&[],
&[],
);
let tree_text = tree.text();
assert!(tree_text.contains("README.md"));
assert!(tree_text.contains("binary.dat"));
assert!(tree_text.contains("non-å.txt"));
assert!(tree_text.contains("non-%C3%A5.txt"));
assert!(tree_text.contains("<img src=x onerror=alert(4)>.txt"));
assert!(!tree_text.contains("<img"));
let blob = request(
server.address(),
"GET",
&format!("/alice/example/blob/{}/nested/file.txt", fixture.head),
&[],
&[],
);
assert!(blob.text().contains("second line"));
assert!(blob.text().contains(&format!(
"/alice/example/raw/{}/nested/file.txt",
fixture.head
)));
let binary = request(
server.address(),
"GET",
&format!("/alice/example/blob/{}/binary.dat", fixture.head),
&[],
&[],
);
assert_eq!(binary.status, 200);
assert!(binary.text().contains("Binary content cannot be shown."));
let large = request(
server.address(),
"GET",
&format!("/alice/example/blob/{}/large.txt", fixture.head),
&[],
&[],
);
assert_eq!(large.status, 200);
assert!(large.body.len() > 2 * 1024 * 1024);
assert!(large.text().contains("large content starts"));
assert!(large.text().contains("large content ends"));
let raw = request(
server.address(),
"GET",
&format!("/alice/example/raw/{}/nested/file.txt", fixture.head),
&[],
&[],
);
assert_eq!(raw.status, 200);
assert_eq!(raw.header("content-type"), "application/octet-stream");
assert_eq!(raw.body, b"first line\nsecond line\n");
assert_eq!(
raw.header("cache-control"),
"public, max-age=31536000, immutable"
);
let raw_head = request(
server.address(),
"HEAD",
&format!("/alice/example/raw/{}/nested/file.txt", fixture.head),
&[],
&[],
);
assert_eq!(raw_head.status, 200);
assert!(raw_head.body.is_empty());
assert_eq!(
raw_head.header("content-length"),
raw.body.len().to_string()
);
let non_utf8 = request(
server.address(),
"GET",
&format!("/alice/example/raw/{}/non-%C3%A5.txt", fixture.head),
&[],
&[],
);
assert_eq!(non_utf8.status, 200);
assert_eq!(non_utf8.body, b"non-UTF-8 path\n");
let missing_non_utf8 = request(
server.address(),
"GET",
&format!("/alice/example/raw/{}/missing-%FF.txt", fixture.head),
&[],
&[],
);
assert_eq!(missing_non_utf8.status, 404);
assert_html_policy(&missing_non_utf8);
let archive = request(
server.address(),
"GET",
&format!("/alice/example/archive/{}.tar", fixture.head),
&[],
&[],
);
assert_eq!(archive.status, 200);
assert_eq!(archive.header("content-type"), "application/x-tar");
assert!(archive.body.ends_with(&[0_u8; 1024]));
let archive_head = request(
server.address(),
"HEAD",
&format!("/alice/example/archive/{}.tar", fixture.head),
&[],
&[],
);
assert_eq!(archive_head.status, 200);
assert!(archive_head.body.is_empty());
let archive_path = fixture.instance.path().join(format!("{format}.tar"));
fs::write(&archive_path, &archive.body).expect("write the public archive");
let listed = Command::new("tar")
.arg("-tf")
.arg(&archive_path)
.output()
.expect("run the system tar reader");
assert!(listed.status.success());
let names = String::from_utf8_lossy(&listed.stdout);
assert!(names.contains("README.md"));
assert!(names.contains("nested/file.txt"));
let discovery = request(
server.address(),
"GET",
"/alice/example.git/info/refs?service=git-upload-pack",
&[("Git-Protocol", "version=2")],
&[],
);
assert_eq!(discovery.status, 200);
assert_eq!(
discovery.header("content-type"),
"application/x-git-upload-pack-advertisement"
);
assert!(
discovery
.body
.windows(b"version 2".len())
.any(|window| window == b"version 2")
);
assert_eq!(
request(
server.address(),
"GET",
"/alice/example/info/refs?service=git-receive-pack",
&[],
&[],
)
.status,
400
);
assert_eq!(
request(
server.address(),
"GET",
"/alice/example/info/refs?service=git-upload-pack",
&[("Git-Protocol", "version=3")],
&[],
)
.status,
400
);
assert_eq!(
request(
server.address(),
"POST",
"/alice/example/git-upload-pack",
&[("Content-Type", "text/plain")],
b"0000",
)
.status,
415
);
assert_eq!(
request(
server.address(),
"POST",
"/alice/example/git-upload-pack",
&[
("Content-Type", "application/x-git-upload-pack-request"),
("Git-Protocol", "version=2"),
],
b"zzzz",
)
.status,
400
);
assert_eq!(
request(
server.address(),
"POST",
"/alice/example/git-upload-pack",
&[("Content-Type", "application/x-git-upload-pack-request")],
&vec![b'0'; git::packetline::MAX_REQUEST_BYTES + 1],
)
.status,
413
);
let clone = fixture.instance.path().join(format!("clone-{format}"));
run(Command::new("git")
.args(["-c", "protocol.version=2", "clone", "-q"])
.arg(format!("http://{}/alice/example.git", server.address()))
.arg(&clone));
assert_eq!(rev_parse(&clone, "HEAD"), fixture.head);
assert_eq!(
fs::read(clone.join("nested/file.txt")).expect("read the cloned file"),
b"first line\nsecond line\n"
);
for route in [
"/alice/missing",
"/Alice/example",
"/alice/example/commit/not-an-object",
"/alice/example/tree/0000000000000000000000000000000000000000",
"/alice/example/raw/0000000000000000000000000000000000000000/file",
] {
let response = request(server.address(), "GET", route, &[], &[]);
assert_eq!(response.status, 404, "route leaked or accepted: {route}");
assert_html_policy(&response);
}
let database = fixture.instance.path().join(store::DATABASE_FILE);
let hidden = Store::open(&database).expect("open the repository database");
hidden
.connection()
.execute(
"UPDATE repository SET visibility = 'private' WHERE slug = 'example'",
[],
)
.expect("make the repository private");
drop(hidden);
assert_hidden(server.address(), &fixture.head);
let archived = Store::open(&database).expect("reopen the repository database");
archived
.connection()
.execute(
"UPDATE repository
SET visibility = 'public', state = 'archived', archived_at = 3
WHERE slug = 'example'",
[],
)
.expect("archive the repository");
drop(archived);
assert_hidden(server.address(), &fixture.head);
server.shutdown().await.expect("stop the public Web server");
}
}
fn assert_hidden(address: SocketAddr, head: &str) {
for route in [
"/alice/example".to_owned(),
format!("/alice/example/raw/{head}/README.md"),
"/alice/example/atom.xml".to_owned(),
"/alice/example/rss.xml".to_owned(),
"/alice/example/search?q=text".to_owned(),
"/alice/example/info/refs?service=git-upload-pack".to_owned(),
] {
let response = request(address, "GET", &route, &[], &[]);
assert_eq!(response.status, 404, "repository was visible at {route}");
}
}
struct Fixture {
instance: TempDir,
repository_id: String,
head: String,
parent: String,
}
impl Fixture {
fn new(format: &str) -> Self {
let instance = TempDir::new().expect("create an instance directory");
let repositories = instance.path().join("repositories");
fs::create_dir(&repositories).expect("create the repository directory");
let id = if format == "sha1" {
"11111111111111111111111111111111"
} else {
"22222222222222222222222222222222"
};
let bare = repositories.join(format!("{id}.git"));
let empty_bare = repositories.join("33333333333333333333333333333333.git");
let worktree = instance.path().join("worktree");
run(Command::new("git")
.args(["init", "-q", "-b", "main", "--object-format", format])
.arg(&worktree));
run(Command::new("git").arg("-C").arg(&worktree).args([
"config",
"commit.gpgsign",
"false",
]));
fs::write(
worktree.join("README.md"),
b"# tit fixture\n\n**safe** and `<safe>`\n\n[guide](docs/guide.md) [bad](javascript:alert(1))\n\n\n\n<script>alert(2)</script>\n",
)
.expect("write the README");
fs::create_dir(worktree.join("nested")).expect("create a nested directory");
fs::write(worktree.join("nested/file.txt"), b"first line\n").expect("write the text file");
fs::write(worktree.join("binary.dat"), b"binary\0content").expect("write the binary file");
let mut large = vec![b'x'; 2 * 1024 * 1024];
let prefix = b"large content starts\n";
large[..prefix.len()].copy_from_slice(prefix);
let suffix = b"\nlarge content ends\n";
let suffix_start = large.len() - suffix.len();
large[suffix_start..].copy_from_slice(suffix);
fs::write(worktree.join("large.txt"), large).expect("write the large file");
fs::write(
worktree.join("<img src=x onerror=alert(4)>.txt"),
b"escaped path\n",
)
.expect("write the hostile path");
fs::write(worktree.join("non-å.txt"), b"non-UTF-8 path\n")
.expect("write the percent-encoded path");
fs::write(worktree.join("malformed.txt"), b"start \xff needle\n")
.expect("write malformed UTF-8 content");
commit_all(&worktree, "first commit");
let parent = rev_parse(&worktree, "HEAD");
fs::write(
worktree.join("nested/file.txt"),
b"first line\nsecond line\n",
)
.expect("update the text file");
commit_all(&worktree, "<script>alert(3)</script>");
let head = rev_parse(&worktree, "HEAD");
run(Command::new("git")
.args(["init", "-q", "--bare", "--object-format", format])
.arg(&bare));
run(Command::new("git")
.args(["init", "-q", "--bare", "--object-format", format])
.arg(&empty_bare));
run(Command::new("git").arg("-C").arg(&bare).args([
"symbolic-ref",
"HEAD",
"refs/heads/main",
]));
run(Command::new("git")
.arg("-C")
.arg(&worktree)
.args(["push", "-q"])
.arg(&bare)
.arg("main"));
let database = instance.path().join(store::DATABASE_FILE);
let mut store = Store::open(&database).expect("open the fixture database");
store
.create_initial_administrator(&InitialAdministrator {
username: "alice",
canonical_key: "ssh-ed25519 AAAA",
fingerprint: "SHA256:fixture",
recovery_hash: &[7_u8; 32],
created_at: 1,
})
.expect("create the repository owner");
store
.create_repository(&NewRepository {
id,
owner: "alice",
slug: "example",
object_format: format,
created_at: 2,
origin: RepositoryOrigin::Imported,
initial_references: &[],
actor: "admin-cli",
correlation_id: "test-import",
})
.expect("create the repository record");
store
.create_repository(&NewRepository {
id: "33333333333333333333333333333333",
owner: "alice",
slug: "empty",
object_format: format,
created_at: 2,
origin: RepositoryOrigin::Created,
initial_references: &[],
actor: "admin-cli",
correlation_id: "test-create",
})
.expect("create the empty repository record");
drop(store);
Self {
instance,
repository_id: id.to_owned(),
head,
parent,
}
}
}
fn commit_all(worktree: &Path, message: &str) {
run(Command::new("git")
.arg("-C")
.arg(worktree)
.args(["add", "-A"]));
run(Command::new("git")
.arg("-C")
.arg(worktree)
.args(["commit", "-q", "-m", message])
.env("GIT_AUTHOR_NAME", "Fixture Author")
.env("GIT_AUTHOR_EMAIL", "fixture@example.test")
.env("GIT_COMMITTER_NAME", "Fixture Author")
.env("GIT_COMMITTER_EMAIL", "fixture@example.test"));
}
fn rev_parse(repository: &Path, revision: &str) -> String {
let output = Command::new("git")
.arg("-C")
.arg(repository)
.args(["rev-parse", revision])
.output()
.expect("read a Git object ID");
assert!(output.status.success());
String::from_utf8(output.stdout)
.expect("a hexadecimal object ID")
.trim()
.to_owned()
}
fn run(command: &mut Command) {
let output = command.output().expect("run a fixture command");
assert!(
output.status.success(),
"command failed: {}",
String::from_utf8_lossy(&output.stderr)
);
}
fn request(
address: SocketAddr,
method: &str,
path: &str,
headers: &[(&str, &str)],
body: &[u8],
) -> HttpResponse {
let mut stream = TcpStream::connect(address).expect("connect to the public Web server");
let mut head = format!(
"{method} {path} HTTP/1.1\r\nHost: {address}\r\nConnection: close\r\nContent-Length: {}\r\n",
body.len()
);
for (name, value) in headers {
head.push_str(&format!("{name}: {value}\r\n"));
}
head.push_str("\r\n");
stream
.write_all(head.as_bytes())
.and_then(|()| stream.write_all(body))
.expect("write an HTTP request");
let mut response = Vec::new();
stream
.read_to_end(&mut response)
.expect("read an HTTP response");
HttpResponse::parse(&response)
}
fn assert_html_policy(response: &HttpResponse) {
assert_eq!(response.header("content-type"), "text/html; charset=utf-8");
assert_eq!(response.header("x-content-type-options"), "nosniff");
assert_eq!(response.header("x-frame-options"), "DENY");
assert_eq!(response.header("referrer-policy"), "no-referrer");
assert_eq!(response.header("cache-control"), "no-store");
assert_eq!(response.header("x-request-id").len(), 32);
}
struct HttpResponse {
status: u16,
headers: BTreeMap<String, String>,
body: Vec<u8>,
}
impl HttpResponse {
fn parse(bytes: &[u8]) -> Self {
let split = bytes
.windows(4)
.position(|window| window == b"\r\n\r\n")
.expect("an HTTP response header terminator");
let head = std::str::from_utf8(&bytes[..split]).expect("UTF-8 HTTP response headers");
let mut lines = head.split("\r\n");
let status = lines
.next()
.expect("an HTTP status line")
.split_whitespace()
.nth(1)
.expect("an HTTP status code")
.parse()
.expect("a numeric HTTP status code");
let headers = lines
.map(|line| {
let (name, value) = line.split_once(':').expect("a valid HTTP response header");
(name.to_ascii_lowercase(), value.trim().to_owned())
})
.collect::<BTreeMap<_, _>>();
let raw_body = &bytes[split + 4..];
let body = if headers.get("transfer-encoding").map(String::as_str) == Some("chunked") {
decode_chunked(raw_body)
} else {
raw_body.to_vec()
};
Self {
status,
headers,
body,
}
}
fn header(&self, name: &str) -> &str {
self.headers
.get(name)
.unwrap_or_else(|| panic!("missing {name} response header"))
}
fn text(&self) -> &str {
std::str::from_utf8(&self.body).expect("a UTF-8 response body")
}
}
fn decode_chunked(mut input: &[u8]) -> Vec<u8> {
let mut output = Vec::new();
loop {
let line_end = input
.windows(2)
.position(|window| window == b"\r\n")
.expect("a chunk-size terminator");
let size_text = std::str::from_utf8(&input[..line_end]).expect("an ASCII chunk size");
let size = usize::from_str_radix(size_text.split(';').next().expect("a chunk size"), 16)
.expect("a hexadecimal chunk size");
input = &input[line_end + 2..];
if size == 0 {
break;
}
assert!(input.len() >= size + 2, "a complete HTTP chunk");
output.extend_from_slice(&input[..size]);
assert_eq!(&input[size..size + 2], b"\r\n");
input = &input[size + 2..];
}
output
}