Full migration and transition to Rust; Remove python artifacts

crates/myfsio-auth/src/sigv4.rs

@@ -0,0 +1,287 @@
+use hmac::{Hmac, Mac};
+use lru::LruCache;
+use parking_lot::Mutex;
+use percent_encoding::{percent_encode, AsciiSet, NON_ALPHANUMERIC};
+use sha2::{Digest, Sha256};
+use std::num::NonZeroUsize;
+use std::sync::LazyLock;
+use std::time::Instant;
+
+type HmacSha256 = Hmac<Sha256>;
+
+struct CacheEntry {
+    key: Vec<u8>,
+    created: Instant,
+}
+
+static SIGNING_KEY_CACHE: LazyLock<Mutex<LruCache<(String, String, String, String), CacheEntry>>> =
+    LazyLock::new(|| Mutex::new(LruCache::new(NonZeroUsize::new(256).unwrap())));
+
+const CACHE_TTL_SECS: u64 = 60;
+
+const AWS_ENCODE_SET: &AsciiSet = &NON_ALPHANUMERIC
+    .remove(b'-')
+    .remove(b'_')
+    .remove(b'.')
+    .remove(b'~');
+
+fn hmac_sha256(key: &[u8], msg: &[u8]) -> Vec<u8> {
+    let mut mac = HmacSha256::new_from_slice(key).expect("HMAC key length is always valid");
+    mac.update(msg);
+    mac.finalize().into_bytes().to_vec()
+}
+
+fn sha256_hex(data: &[u8]) -> String {
+    let mut hasher = Sha256::new();
+    hasher.update(data);
+    hex::encode(hasher.finalize())
+}
+
+fn aws_uri_encode(input: &str) -> String {
+    percent_encode(input.as_bytes(), AWS_ENCODE_SET).to_string()
+}
+
+pub fn derive_signing_key_cached(
+    secret_key: &str,
+    date_stamp: &str,
+    region: &str,
+    service: &str,
+) -> Vec<u8> {
+    let cache_key = (
+        secret_key.to_owned(),
+        date_stamp.to_owned(),
+        region.to_owned(),
+        service.to_owned(),
+    );
+
+    {
+        let mut cache = SIGNING_KEY_CACHE.lock();
+        if let Some(entry) = cache.get(&cache_key) {
+            if entry.created.elapsed().as_secs() < CACHE_TTL_SECS {
+                return entry.key.clone();
+            }
+            cache.pop(&cache_key);
+        }
+    }
+
+    let k_date = hmac_sha256(
+        format!("AWS4{}", secret_key).as_bytes(),
+        date_stamp.as_bytes(),
+    );
+    let k_region = hmac_sha256(&k_date, region.as_bytes());
+    let k_service = hmac_sha256(&k_region, service.as_bytes());
+    let k_signing = hmac_sha256(&k_service, b"aws4_request");
+
+    {
+        let mut cache = SIGNING_KEY_CACHE.lock();
+        cache.put(
+            cache_key,
+            CacheEntry {
+                key: k_signing.clone(),
+                created: Instant::now(),
+            },
+        );
+    }
+
+    k_signing
+}
+
+fn constant_time_compare_inner(a: &[u8], b: &[u8]) -> bool {
+    if a.len() != b.len() {
+        return false;
+    }
+    let mut result: u8 = 0;
+    for (x, y) in a.iter().zip(b.iter()) {
+        result |= x ^ y;
+    }
+    result == 0
+}
+
+pub fn verify_sigv4_signature(
+    method: &str,
+    canonical_uri: &str,
+    query_params: &[(String, String)],
+    signed_headers_str: &str,
+    header_values: &[(String, String)],
+    payload_hash: &str,
+    amz_date: &str,
+    date_stamp: &str,
+    region: &str,
+    service: &str,
+    secret_key: &str,
+    provided_signature: &str,
+) -> bool {
+    let mut sorted_params = query_params.to_vec();
+    sorted_params.sort_by(|a, b| a.0.cmp(&b.0).then_with(|| a.1.cmp(&b.1)));
+
+    let canonical_query_string = sorted_params
+        .iter()
+        .map(|(k, v)| format!("{}={}", aws_uri_encode(k), aws_uri_encode(v)))
+        .collect::<Vec<_>>()
+        .join("&");
+
+    let mut canonical_headers = String::new();
+    for (name, value) in header_values {
+        let lower_name = name.to_lowercase();
+        let normalized = value.split_whitespace().collect::<Vec<_>>().join(" ");
+        let final_value = if lower_name == "expect" && normalized.is_empty() {
+            "100-continue"
+        } else {
+            &normalized
+        };
+        canonical_headers.push_str(&lower_name);
+        canonical_headers.push(':');
+        canonical_headers.push_str(final_value);
+        canonical_headers.push('\n');
+    }
+
+    let canonical_request = format!(
+        "{}\n{}\n{}\n{}\n{}\n{}",
+        method,
+        canonical_uri,
+        canonical_query_string,
+        canonical_headers,
+        signed_headers_str,
+        payload_hash
+    );
+
+    let credential_scope = format!("{}/{}/{}/aws4_request", date_stamp, region, service);
+    let cr_hash = sha256_hex(canonical_request.as_bytes());
+    let string_to_sign = format!(
+        "AWS4-HMAC-SHA256\n{}\n{}\n{}",
+        amz_date, credential_scope, cr_hash
+    );
+
+    let signing_key = derive_signing_key_cached(secret_key, date_stamp, region, service);
+    let calculated = hmac_sha256(&signing_key, string_to_sign.as_bytes());
+    let calculated_hex = hex::encode(&calculated);
+
+    constant_time_compare_inner(calculated_hex.as_bytes(), provided_signature.as_bytes())
+}
+
+pub fn derive_signing_key(
+    secret_key: &str,
+    date_stamp: &str,
+    region: &str,
+    service: &str,
+) -> Vec<u8> {
+    derive_signing_key_cached(secret_key, date_stamp, region, service)
+}
+
+pub fn compute_signature(signing_key: &[u8], string_to_sign: &str) -> String {
+    let sig = hmac_sha256(signing_key, string_to_sign.as_bytes());
+    hex::encode(sig)
+}
+
+pub fn compute_post_policy_signature(signing_key: &[u8], policy_b64: &str) -> String {
+    let sig = hmac_sha256(signing_key, policy_b64.as_bytes());
+    hex::encode(sig)
+}
+
+pub fn build_string_to_sign(
+    amz_date: &str,
+    credential_scope: &str,
+    canonical_request: &str,
+) -> String {
+    let cr_hash = sha256_hex(canonical_request.as_bytes());
+    format!(
+        "AWS4-HMAC-SHA256\n{}\n{}\n{}",
+        amz_date, credential_scope, cr_hash
+    )
+}
+
+pub fn constant_time_compare(a: &str, b: &str) -> bool {
+    constant_time_compare_inner(a.as_bytes(), b.as_bytes())
+}
+
+pub fn clear_signing_key_cache() {
+    SIGNING_KEY_CACHE.lock().clear();
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_derive_signing_key() {
+        let key = derive_signing_key(
+            "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY",
+            "20130524",
+            "us-east-1",
+            "s3",
+        );
+        assert_eq!(key.len(), 32);
+    }
+
+    #[test]
+    fn test_derive_signing_key_cached() {
+        let key1 = derive_signing_key("secret", "20240101", "us-east-1", "s3");
+        let key2 = derive_signing_key("secret", "20240101", "us-east-1", "s3");
+        assert_eq!(key1, key2);
+    }
+
+    #[test]
+    fn test_constant_time_compare() {
+        assert!(constant_time_compare("abc", "abc"));
+        assert!(!constant_time_compare("abc", "abd"));
+        assert!(!constant_time_compare("abc", "abcd"));
+    }
+
+    #[test]
+    fn test_build_string_to_sign() {
+        let result = build_string_to_sign(
+            "20130524T000000Z",
+            "20130524/us-east-1/s3/aws4_request",
+            "GET\n/\n\nhost:example.com\n\nhost\nUNSIGNED-PAYLOAD",
+        );
+        assert!(result.starts_with("AWS4-HMAC-SHA256\n"));
+        assert!(result.contains("20130524T000000Z"));
+    }
+
+    #[test]
+    fn test_aws_uri_encode() {
+        assert_eq!(aws_uri_encode("hello world"), "hello%20world");
+        assert_eq!(aws_uri_encode("test-file_name.txt"), "test-file_name.txt");
+        assert_eq!(aws_uri_encode("a/b"), "a%2Fb");
+    }
+
+    #[test]
+    fn test_verify_sigv4_roundtrip() {
+        let secret = "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY";
+        let date_stamp = "20130524";
+        let region = "us-east-1";
+        let service = "s3";
+        let amz_date = "20130524T000000Z";
+
+        let signing_key = derive_signing_key(secret, date_stamp, region, service);
+
+        let canonical_request =
+            "GET\n/\n\nhost:examplebucket.s3.amazonaws.com\n\nhost\nUNSIGNED-PAYLOAD";
+        let string_to_sign = build_string_to_sign(
+            amz_date,
+            &format!("{}/{}/{}/aws4_request", date_stamp, region, service),
+            canonical_request,
+        );
+
+        let signature = compute_signature(&signing_key, &string_to_sign);
+
+        let result = verify_sigv4_signature(
+            "GET",
+            "/",
+            &[],
+            "host",
+            &[(
+                "host".to_string(),
+                "examplebucket.s3.amazonaws.com".to_string(),
+            )],
+            "UNSIGNED-PAYLOAD",
+            amz_date,
+            date_stamp,
+            region,
+            service,
+            secret,
+            &signature,
+        );
+        assert!(result);
+    }
+}