stricter idty name validation

Avoid phishing by requiring identity names to be ASCII alphanumeric and punctuation only.

Closes #47 (closed)

runtime/common/src/lib.rs

@@ -83,7 +83,20 @@ impl<Runtime: pallet_babe::Config> frame_support::pallet_prelude::Get<u64>
 
 pub struct IdtyNameValidatorImpl;
 impl pallet_identity::traits::IdtyNameValidator for IdtyNameValidatorImpl {
+    // Bound length; forbid trailing or double spaces; accept only ascii alphanumeric or punctuation or space
     fn validate(idty_name: &pallet_identity::IdtyName) -> bool {
-        idty_name.0.len() >= 3 && idty_name.0.len() <= 64
+        idty_name.0.len() >= 3
+            && idty_name.0.len() <= 64
+            && idty_name.0[0] != 32
+            && idty_name.0[idty_name.0.len() - 1] != 32
+            && idty_name
+                .0
+                .iter()
+                .all(|c| c.is_ascii_alphanumeric() || c.is_ascii_punctuation() || *c == 32)
+            && idty_name
+                .0
+                .iter()
+                .zip(idty_name.0.iter().skip(1))
+                .all(|(c1, c2)| *c1 != 32 || *c2 != 32)
     }
 }