lykin_tutorial/part_5_task_loop/src/utils.rs

33 lines
1.1 KiB
Rust

//! Public key validation.
/// Ensure that the given public key is a valid ed25519 key.
///
/// Return an error string if the key is invalid.
pub fn validate_public_key(public_key: &str) -> Result<(), String> {
// Ensure the ID starts with the correct sigil link.
if !public_key.starts_with('@') {
return Err("expected '@' sigil as first character".to_string());
}
// Find the dot index denoting the start of the algorithm definition tag.
let dot_index = match public_key.rfind('.') {
Some(index) => index,
None => return Err("no dot index was found".to_string()),
};
// Check the hashing algorithm (must end with ".ed25519").
if !&public_key.ends_with(".ed25519") {
return Err("hashing algorithm must be ed25519".to_string());
}
// Obtain the base64 portion (substring) of the public key.
let base64_str = &public_key[1..dot_index];
// Ensure the length of the base64 encoded ed25519 public key is correct.
if base64_str.len() != 44 {
return Err("base64 data length is incorrect".to_string());
}
Ok(())
}