programs: backward compatible instruction args deserialization (#1949)

## Summary of Changes
- Add a [new crate](https://github.com/malbeclabs/borsh-incremental-rs)
providing the `BorshDeserializeIncremental` derive macro for incremental
deserialization of structs with per-field defaults.
- Enables decoding to succeed when new fields are added, allowing
backward-compatible evolution of instruction argument types and onchain
state layouts, without breaking interaction of existing clients and
components.
- Generalizes the manual partial-decode pattern used for [state
objects](https://github.com/malbeclabs/doublezero/blob/main/smartcontract/programs/doublezero-serviceability/src/state/accesspass.rs#L184-L199),
so we no longer have to hand-write incremental deserialization for each
type.
- Update serviceability and telemetry program instruction args to use
the derive.
- Resolves #1950

## Testing Verification
- Added test coverage for the new derive macro, including default
fallbacks and partial input handling.

Author: snormore

CHANGELOG.md

@@ -10,6 +10,7 @@ All notable changes to this project will be documented in this file.
 
 - Onchain programs
     - serviceability: add auto-assignment and validation for exchange.bgp_community
+    - Update serviceability and telemetry program instruction args to use the `BorshDeserializeIncremental` derive macro incremental, backward-compatible, deserialization of structs.
 - CLI
     - Removed `--bgp-community` option from `doublezero exchange create` since these values are now assigned automatically
     - Add `--next-bgp-community` option to `doublezero global-config set` so authorized users can control which bgp_community will be assigned next

Cargo.lock

@@ -34,6 +34,7 @@ base64 = "0.22.1"
 bincode = { version = "2", features = ["serde"] }
 bitvec = "1"
 borsh = "1"
+borsh-incremental = { version = "0" }
 bytemuck = { version = "1", features = ["derive"] }
 byteorder = "1"
 chrono = "0"

Cargo.toml

@@ -189,7 +189,7 @@ mod tests {
                 .times(1)
                 .in_sequence(&mut seq)
                 .with(
-                    predicate::eq(DoubleZeroInstruction::ActivateDevice(DeviceActivateArgs)),
+                    predicate::eq(DoubleZeroInstruction::ActivateDevice(DeviceActivateArgs {})),
                     predicate::always(),
                 )
                 .returning(|_, _| Ok(Signature::new_unique()));

activator/src/process/device.rs

@@ -17,6 +17,7 @@ crate-type = ["cdylib", "lib"]
 
 [dependencies]
 borsh.workspace = true
+borsh-incremental.workspace = true
 doublezero-program-common.workspace = true
 ipnetwork.workspace = true
 serde = { workspace = true, optional = true }

smartcontract/programs/doublezero-serviceability/Cargo.toml

@@ -3,7 +3,8 @@ use crate::{
     globalstate::globalstate_get,
     state::{accesspass::AccessPass, accounttype::AccountTypeInfo},
 };
-use borsh::{BorshDeserialize, BorshSerialize};
+use borsh::BorshSerialize;
+use borsh_incremental::BorshDeserializeIncremental;
 use core::fmt;
 use doublezero_program_common::resize_account::resize_account_if_needed;
 use solana_program::{
@@ -13,7 +14,7 @@ use solana_program::{
     pubkey::Pubkey,
 };
 
-#[derive(BorshSerialize, BorshDeserialize, PartialEq, Clone, Default)]
+#[derive(BorshSerialize, BorshDeserializeIncremental, PartialEq, Clone, Default)]
 pub struct CheckStatusAccessPassArgs {}
 
 impl fmt::Debug for CheckStatusAccessPassArgs {

smartcontract/programs/doublezero-serviceability/src/instructions.rs

@@ -2,7 +2,8 @@ use crate::{
     error::DoubleZeroError, globalstate::globalstate_get, helper::account_close,
     state::accounttype::AccountType,
 };
-use borsh::{BorshDeserialize, BorshSerialize};
+use borsh::BorshSerialize;
+use borsh_incremental::BorshDeserializeIncremental;
 use core::fmt;
 use solana_program::{
     account_info::{next_account_info, AccountInfo},
@@ -11,7 +12,7 @@ use solana_program::{
     pubkey::Pubkey,
 };
 
-#[derive(BorshSerialize, BorshDeserialize, PartialEq, Clone, Default)]
+#[derive(BorshSerialize, BorshDeserializeIncremental, PartialEq, Clone, Default)]
 pub struct CloseAccessPassArgs {}
 
 impl fmt::Debug for CloseAccessPassArgs {

smartcontract/programs/doublezero-serviceability/src/processors/accesspass/check_status.rs

@@ -11,7 +11,8 @@ use crate::{
         accounttype::{AccountType, AccountTypeInfo},
     },
 };
-use borsh::{BorshDeserialize, BorshSerialize};
+use borsh::BorshSerialize;
+use borsh_incremental::BorshDeserializeIncremental;
 use doublezero_program_common::{resize_account::resize_account_if_needed, try_create_account};
 use solana_program::{
     account_info::{next_account_info, AccountInfo},
@@ -29,10 +30,11 @@ use solana_program::{
 // `User` account size assumes a single publisher and subscriber pubkey registered
 const AIRDROP_USER_RENT_LAMPORTS_BYTES: usize = 236 * 3; // 236 bytes per User account x 3 accounts = 708 bytes
 
-#[derive(BorshSerialize, BorshDeserialize, PartialEq, Clone)]
+#[derive(BorshSerialize, BorshDeserializeIncremental, PartialEq, Clone)]
 pub struct SetAccessPassArgs {
     pub accesspass_type: AccessPassType, // 1 or 33
-    pub client_ip: Ipv4Addr,             // 4
+    #[incremental(default = Ipv4Addr::UNSPECIFIED)]
+    pub client_ip: Ipv4Addr, // 4
     pub last_access_epoch: u64,          // 8
     pub allow_multiple_ip: bool,         // 1
 }

smartcontract/programs/doublezero-serviceability/src/processors/accesspass/close.rs

@@ -5,7 +5,8 @@ use crate::{
     globalstate::{globalstate_get, globalstate_write_with_realloc},
     pda::*,
 };
-use borsh::{BorshDeserialize, BorshSerialize};
+use borsh::BorshSerialize;
+use borsh_incremental::BorshDeserializeIncremental;
 #[cfg(test)]
 use solana_program::msg;
 use solana_program::{
@@ -15,7 +16,7 @@ use solana_program::{
     pubkey::Pubkey,
 };
 
-#[derive(BorshSerialize, BorshDeserialize, PartialEq, Clone, Default)]
+#[derive(BorshSerialize, BorshDeserializeIncremental, PartialEq, Clone, Default)]
 pub struct AddDeviceAllowlistArgs {
     pub pubkey: Pubkey,
 }