[book] add the toml related stuff to the algebra chapter (#1063)

* Add the toml part to the algebra book chapter, also add the BigUint deserializer

* Add a "no-hexadecimal" part

book/src/custom-extensions/algebra.md

@@ -141,3 +141,17 @@ pub fn main() {
     // Note that these assertions would fail, have we provided the `mod_idx` parameters wrongly.
 }
 ```
+
+### Config parameters
+
+For the guest program to build successfully, all used moduli must be declared in the `.toml` config file in the following format:
+
+```toml
+[app_vm_config.modular]
+supported_modulus = ["115792089237316195423570985008687907853269984665640564039457584007908834671663"]
+
+[app_vm_config.fp2]
+supported_modulus = ["115792089237316195423570985008687907853269984665640564039457584007908834671663"]
+```
+
+The `supported_modulus` parameter is a list of moduli that the guest program will use. They must be provided in decimal format in the `.toml` file.

crates/cli/Cargo.toml

@@ -47,6 +47,7 @@ prettytable-rs = "0.10"
 textwrap = "0.16.0"
 ctrlc = "3.4.2"
 toml = { workspace = true }
+num-bigint-dig = { workspace = true, features = ["serde"] }
 
 [dev-dependencies]
 openvm-cli-example-test = { path = "example" }

extensions/algebra/circuit/src/fp2_extension.rs

@@ -19,10 +19,14 @@ use openvm_stark_backend::p3_field::PrimeField32;
 use serde::{Deserialize, Serialize};
 use strum::EnumCount;
 
-use crate::fp2_chip::{Fp2AddSubChip, Fp2MulDivChip};
+use crate::{
+    fp2_chip::{Fp2AddSubChip, Fp2MulDivChip},
+    util::deserialize_vec_biguint_from_str,
+};
 
 #[derive(Clone, Debug, derive_new::new, Serialize, Deserialize)]
 pub struct Fp2Extension {
+    #[serde(deserialize_with = "deserialize_vec_biguint_from_str")]
     pub supported_modulus: Vec<BigUint>,
 }
 

extensions/algebra/circuit/src/lib.rs

@@ -1,6 +1,8 @@
 pub mod fp2_chip;
 pub mod modular_chip;
 
+mod util;
+
 mod fp2;
 pub use fp2::*;
 mod modular_extension;

extensions/algebra/circuit/src/modular_extension.rs

@@ -20,13 +20,17 @@ use openvm_stark_backend::p3_field::PrimeField32;
 use serde::{Deserialize, Serialize};
 use strum::EnumCount;
 
-use crate::modular_chip::{
-    ModularAddSubChip, ModularAddSubCoreChip, ModularIsEqualChip, ModularIsEqualCoreChip,
-    ModularMulDivChip, ModularMulDivCoreChip,
+use crate::{
+    modular_chip::{
+        ModularAddSubChip, ModularAddSubCoreChip, ModularIsEqualChip, ModularIsEqualCoreChip,
+        ModularMulDivChip, ModularMulDivCoreChip,
+    },
+    util::deserialize_vec_biguint_from_str,
 };
 
 #[derive(Clone, Debug, derive_new::new, Serialize, Deserialize)]
 pub struct ModularExtension {
+    #[serde(deserialize_with = "deserialize_vec_biguint_from_str")]
     pub supported_modulus: Vec<BigUint>,
 }
 

extensions/algebra/circuit/src/util.rs

@@ -0,0 +1,16 @@
+use num_bigint_dig::BigUint;
+use serde::Deserialize;
+
+pub(crate) fn deserialize_vec_biguint_from_str<'de, D>(
+    deserializer: D,
+) -> Result<Vec<BigUint>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let v: Vec<String> = Deserialize::deserialize(deserializer)?;
+    let res = v.into_iter().map(|s| s.parse()).collect::<Vec<_>>();
+    if res.iter().any(|x| x.is_err()) {
+        return Err(serde::de::Error::custom("Failed to parse BigUint"));
+    }
+    Ok(res.into_iter().map(|x| x.unwrap()).collect())
+}