Module risc0_zkvm::guest
source · Expand description
The RISC Zero ZKVM’s guest-side RISC-V API.
Code that is validated by the RISC Zero zkVM is run inside the
guest. In the minimal case, an entrypoint (the guest’s “main” function)
must be provided by using the entry! macro. In almost all
practical cases, the guest will want to read private input data using
env::read and commit public output data using env::commit; additional
I/O functionality is also available in env.
For example1, the following guest code proves a number is
composite by multiplying two unsigned integers, and panicking if either is
1 or if the multiplication overflows:
use risc0_zkvm::guest::env;
risc0_zkvm::entry!(main);
pub fn main() {
// Load the first number from the host
let a: u64 = env::read();
// Load the second number from the host
let b: u64 = env::read();
// Verify that neither of them are 1 (i.e. nontrivial factors)
if a == 1 || b == 1 {
panic!("Trivial factors")
}
// Compute the product while being careful with integer overflow
let product = a.checked_mul(b).expect("Integer overflow");
env::commit(&product);
}Notice how the entry! macro is used to indicate the entrypoint, env::read is used to load the two factors, and env::commit is used to make their composite product publically available.
The example is based on the RISC Zero Rust Starter repository. ↩