Crate pbc_zk

Test utility library for testing Zero-Knowledge computations

NOTICE: This library cannot perform MPC; it can only mock MPC.

This library tries to mimic the type system and semantics of the Zero-Knowledge compiler and stack, in order allow contracts to test their contract computations without deploying on the test net. This library is the first testing step for a contract, followed by

1. Integration testing between public contract and computation
2. Full integration testing on test-net.

This library also acts as documentation of the various builtin functions available in the Zk-compiler.

Example Computation of variable summation

Simple example of a computation summing all input variables:

use pbc_zk::{Sbi32, load_sbi, secret_variable_ids, zk_compute};

#[zk_compute(shortname = 0x01)]
pub fn sum_all_variables() -> Sbi32 {
    let mut sum: Sbi32 = Sbi32::from(0);
    for variable_id in secret_variable_ids() {
        sum = sum + load_sbi::<Sbi32>(variable_id);
    }
    sum
}

Example Computation of loading struct

Another example that sums all values of a specific type

use pbc_zk::{Sbi8, Sbi32, secret_variable_ids, load_sbi, SecretBinary, zk_compute};

#[derive(Clone, SecretBinary)]
struct MyStruct {
    variable_type: Sbi8,
    value: Sbi32,
}

#[zk_compute(shortname = 0x02)]
pub fn sum_all_variables() -> Sbi32 {
    let mut sum: Sbi32 = Sbi32::from(0);
    for variable_id in secret_variable_ids() {
        let value = load_sbi::<MyStruct>(variable_id);
        if value.variable_type == Sbi8::from(0) {
            sum = sum + value.value;
        }
    }
    sum
}

Modules

• api
  Module for configuring outside environment of test.

Macros

• test_eq
  Testing macro for Zero-knowledge computations.

Structs

• SecretVarId
  Identifier for a secret variable.

Traits

• FromToBits
  Exposes interface for splitting elements into an array of its composite bits.
• Secret
  Required for secret-shared values. Secret variables are serialized like their public counterparts using the State serialization format.
• SecretBinary
  Required for secret-shared values. Secret variables are serialized like their public counterparts using the State serialization format.
• SecretBinaryFixedSize
  Required for secret-shared values. Used to determine the size of secret-shared inputs.

Functions

• load_metadata
  Retrieve the metadata from variable_id as T.
• load_sbi
  Retrieve the input from variable_id as T.
• num_secret_variablesDeprecated
  Get the number of secret variables.
• save_sbi
  Save the secret variable as an output, allowing for variable number of outputs.
• secret_variable_ids
  Creates an iterator for secret variable ids.

Type Aliases

• Sbi1Deprecated
  A secret-shared bool value. Deprecated, prefer Sbu1.
• Sbi8
  A i8 secret-shared using a binary field.
• Sbi16
  A i16 secret-shared using a binary field.
• Sbi32
  A i32 secret-shared using a binary field.
• Sbi64
  A i64 secret-shared using a binary field.
• Sbi128
  A i128 secret-shared using a binary field.
• Sbu1
  A secret-shared bool value.
• Sbu8
  A u8 secret-shared using a binary field.
• Sbu16
  A u16 secret-shared using a binary field.
• Sbu32
  A u32 secret-shared using a binary field.
• Sbu64
  A u64 secret-shared using a binary field.
• Sbu128
  A u128 secret-shared using a binary field.

Attribute Macros

• zk_compute
  Marks function as a ZK computation entry point with a given shortname.

Derive Macros

• SecretBinary
  Implements #[derive(SecretBinary)].