code import

.gitignore

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+/target
+**/*.rs.bk
+Cargo.lock
+.idea
+

Cargo.toml

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+[package]
+name = "digest_auth"
+version = "0.1.0"
+authors = ["Ondřej Hruška <ondra@ondrovo.com>"]
+edition = "2018"
+
+[dependencies]
+rust-crypto = "0.2"
+rand = "0.6"
+hex = "0.3.2"
+failure = "0.1.5"

src/lib.rs

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+//! This crate implements Digest Auth headers as specified by IETF RFCs 2069, 2617, and 7616.
+//! It can be used in conjunction with libraries like reqwest to access e.g. IP cameras
+//! that use this authentication scheme.
+//!
+//! This library is intended for the http client. The algorithm is symmetrical,
+//! it's just not optimized for / tested on the server side yet.
+//!
+//! # Examples
+//!
+//! Basic usage:
+//!
+//! ```
+//! use digest_auth::AuthContext;
+//!
+//! // Value from the WWW-Authenticate HTTP header (usually in a HTTP 401 response)
+//! let www_authenticate = r#"Digest realm="http-auth@example.org", qop="auth, auth-int", algorithm=MD5, nonce="7ypf/xlj9XXwfDPEoM4URrv/xwf94BcCAzFZH4GiTo0v", opaque="FQhe/qaU925kfnzjCev0ciny7QMkPqMAFRtzCUYo5tdS""#;
+//!
+//! // Prepare an authorization context. Note that this is a GET request. There are different
+//! // constructors available for POST or other request types. You can re-use it, but
+//! // it's cheap to create a fresh one each time, as the struct uses references only.
+//! let mut context = AuthContext::new("Mufasa", "Circle of Life", "/dir/index.html");
+//! // For this test, we inject a custom cnonce. It's generated for you otherwise
+//! // - you don't need `mut` in that case and needn't worry about this at all.
+//! context.set_custom_cnonce("f2/wE4q74E6zIJEtWaHKaf5wv/H5QzzpXusqGemxURZJ");
+//!
+//! // Parse the prompt header. You can inspect the parsed object, its fields are public.
+//! let mut prompt = digest_auth::parse(www_authenticate).unwrap();
+//!
+//! // Compute a value for the Authorization header that we'll send back to the server
+//! let answer = prompt.respond(&context).unwrap().to_string();
+//! assert_eq!(answer, r#"Digest username="Mufasa", realm="http-auth@example.org", nonce="7ypf/xlj9XXwfDPEoM4URrv/xwf94BcCAzFZH4GiTo0v", uri="/dir/index.html", qop=auth, nc=00000001, cnonce="f2/wE4q74E6zIJEtWaHKaf5wv/H5QzzpXusqGemxURZJ", response="8ca523f5e9506fed4657c9700eebdbec", opaque="FQhe/qaU925kfnzjCev0ciny7QMkPqMAFRtzCUYo5tdS", algorithm=MD5"#);
+//!
+//! // The `prompt` variable is mutable, because the 'nc' counter (nonce reuse count)
+//! // is inside the struct and updated automatically.
+//!
+//! // You can re-use it for subsequent requests, assuming the server allows nonce re-use.
+//! // Some poorly implemented servers will reject it and give you 401 again, in which case
+//! // you should parse the new "WWW-Authenticate" header and use that instead.
+//!
+//! let answer2 = prompt.respond(&context).unwrap().to_string();
+//! // notice how the 'response' field changed - the 'nc' counter is included in the hash
+//! assert_eq!(answer2, r#"Digest username="Mufasa", realm="http-auth@example.org", nonce="7ypf/xlj9XXwfDPEoM4URrv/xwf94BcCAzFZH4GiTo0v", uri="/dir/index.html", qop=auth, nc=00000002, cnonce="f2/wE4q74E6zIJEtWaHKaf5wv/H5QzzpXusqGemxURZJ", response="4b5d595ecf2db9df612ea5b45cd97101", opaque="FQhe/qaU925kfnzjCev0ciny7QMkPqMAFRtzCUYo5tdS", algorithm=MD5"#);
+//! ```
+//!
+
+#[macro_use] extern crate failure;
+use failure::Fallible;
+
+mod digest;
+mod utils;
+
+use std::str::FromStr;
+
+pub use crate::digest::{
+    Algorithm, AuthContext, AuthorizationHeader, HttpMethod, Qop, WwwAuthenticateHeader,
+};
+
+/// Parse the WWW-Authorization header value.
+/// It's just a convenience method to call `WwwAuthenticateHeader::from_str()`.
+pub fn parse(www_authorize : &str) -> Fallible<WwwAuthenticateHeader> {
+    WwwAuthenticateHeader::from_str(www_authorize)
+}
+
+#[test]
+fn test_parse_respond() {
+    let src = r#"
+    Digest
+       realm="http-auth@example.org",
+       qop="auth, auth-int",
+       algorithm=MD5,
+       nonce="7ypf/xlj9XXwfDPEoM4URrv/xwf94BcCAzFZH4GiTo0v",
+       opaque="FQhe/qaU925kfnzjCev0ciny7QMkPqMAFRtzCUYo5tdS"
+    "#;
+
+    let mut context = AuthContext::new("Mufasa", "Circle of Life", "/dir/index.html");
+    context.set_custom_cnonce("f2/wE4q74E6zIJEtWaHKaf5wv/H5QzzpXusqGemxURZJ");
+
+    let mut prompt = crate::parse(src).unwrap();
+    let answer = prompt.respond(&context).unwrap();
+
+    let str = answer.to_string().replace(", ", ",\n  ");
+
+    assert_eq!(
+        str,
+        r#"
+Digest username="Mufasa",
+  realm="http-auth@example.org",
+  nonce="7ypf/xlj9XXwfDPEoM4URrv/xwf94BcCAzFZH4GiTo0v",
+  uri="/dir/index.html",
+  qop=auth,
+  nc=00000001,
+  cnonce="f2/wE4q74E6zIJEtWaHKaf5wv/H5QzzpXusqGemxURZJ",
+  response="8ca523f5e9506fed4657c9700eebdbec",
+  opaque="FQhe/qaU925kfnzjCev0ciny7QMkPqMAFRtzCUYo5tdS",
+  algorithm=MD5
+"#
+            .trim()
+    );
+}

src/utils.rs

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+use std::string::ToString;
+
+/// slash quoting for digest strings
+pub trait QuoteForDigest {
+    fn quote_for_digest(&self) -> String;
+}
+
+impl QuoteForDigest for &str {
+    fn quote_for_digest(&self) -> String {
+        self.to_string().quote_for_digest()
+    }
+}
+
+impl QuoteForDigest for String {
+    fn quote_for_digest(&self) -> String {
+        self.replace("\\", "\\\\").replace("\"", "\\\"")
+    }
+}