Security Considerations

Ownership and Authentication#

Authentication schemes can be very simple or complex, fine grained or coarse. This proposal does not limit it in any way, examples -

• Ownership/authentication could be as simple as a single account address having the authority to add/replace/remove functions.

• Decentralized autonomous organization could have the authority to only add/replace/remove certain functions.

  
  • Consensus functionality could be implemented such as an approval function
    • multiple different people call to approve changes before they are executed with the diamondCut function.

The development of standards and implementations of ownership, control and authentication of diamonds is encouraged.

Arbitrary Execution with diamondCut#

The diamondCut function allows arbitrary execution with access to the diamond’s storage (through delegatecall). Access to this function must be restricted carefully.

Do Not Self Destruct#

Use of selfdestruct in a facet is heavily discouraged. Misuse of it can delete a diamond or a facet.

Function Selector Clash#

A function selector clash occurs when two different function signatures hash to the same four-byte hash, replacing an existing function in a diamond when the intention was to add a new function.

• This scenario is not possible with a properly implemented diamondCut function because it prevents adding function selectors that already exist.

Transparency#

Diamonds emit an event every time one or more functions are added, replaced or removed.

• All source code can be verified. This enables people and software to monitor changes to a contract.
• If any bad acting function is added to a diamond then it can be seen.

Security and domain experts can review the history of change of a diamond to detect any history of foul play.