Technology
Hybrid systems
A hybrid CHERI system supports conventional pointers alongside capabilities, allowing selected code or interfaces to adopt capability features while retaining compatibility.
Why it matters
This can be useful for incremental evaluation, operating-system work and components that cannot move together.
In brief
A hybrid CHERI system supports conventional pointers alongside capabilities, allowing selected code or interfaces to adopt capability features while retaining compatibility. Hybrid modes can ease transition and expose CHERI operations without requiring the whole user space to use capabilities as pointers.
Key considerations
1. Boundary
State which code and data use capabilities, which remain conventional and how authority crosses between them.
2. Protection
Distinguish explicit capability use from the broader pointer protection available in a pure-capability ABI.
3. Migration
Use hybrid work to identify assumptions and dependencies, not as an undefined halfway state.
Evidence and caveats
A hybrid binary does not automatically receive pure-capability spatial protection for all pointers. Describe the security coverage precisely.
Use the exact architecture and software specification implemented by the target. Separate architectural guarantees from system-level outcomes.