From 74878fcbeb32fcc00543cee502232ecf722ac58b Mon Sep 17 00:00:00 2001
From: Adeeb Shihadeh <adeebshihadeh@gmail.com>
Date: Sat, 14 Mar 2026 13:40:20 -0700
Subject: [PATCH] automatically handle CAN and health packet ABI versions
 (#2371)

---
 SConscript                   |  9 +++++++++
 board/body/main_comms.h      | 12 ++++++------
 board/health.h               |  4 ----
 board/jungle/__init__.py     | 14 ++++++--------
 board/jungle/jungle_health.h |  3 ---
 board/jungle/main_comms.h    | 12 ++++++------
 board/main_comms.h           | 12 ++++++------
 pyproject.toml               |  4 ++++
 python/__init__.py           | 24 ++++++++++--------------
 python/constants.py          |  5 +++++
 10 files changed, 52 insertions(+), 47 deletions(-)

diff --git a/SConscript b/SConscript
index 6732204d..45abd074 100644
--- a/SConscript
+++ b/SConscript
@@ -1,4 +1,5 @@
 import os
+import hashlib
 import opendbc
 import subprocess
 
@@ -150,6 +151,14 @@ with open("board/obj/cert.h", "w") as f:
   for cert in certs:
     f.write("\n".join(cert) + "\n")
 
+# Packet version defines: SHA hash of the struct header files
+def version_hash(path):
+  with open(path, "rb") as f:
+    return int.from_bytes(hashlib.sha256(f.read()).digest()[:4], 'little')
+hh, ch, jh = version_hash("board/health.h"), version_hash(os.path.join(opendbc.INCLUDE_PATH, "opendbc/safety/can.h")), version_hash("board/jungle/jungle_health.h")
+common_flags += [f"-DHEALTH_PACKET_VERSION=0x{hh:08X}U", f"-DCAN_PACKET_VERSION_HASH=0x{ch:08X}U",
+                 f"-DJUNGLE_HEALTH_PACKET_VERSION=0x{jh:08X}U"]
+
 # panda fw
 build_project("panda_h7", base_project_h7, "./board/main.c", [])
 
diff --git a/board/body/main_comms.h b/board/body/main_comms.h
index 95801332..c80096aa 100644
--- a/board/body/main_comms.h
+++ b/board/body/main_comms.h
@@ -89,13 +89,13 @@ int comms_control_handler(ControlPacket_t *req, uint8_t *resp) {
       break;
     }
 
-    // **** 0xdd: get healthpacket and CANPacket versions
-    case 0xdd:
-      resp[0] = HEALTH_PACKET_VERSION;
-      resp[1] = CAN_PACKET_VERSION;
-      resp[2] = CAN_HEALTH_PACKET_VERSION;
-      resp_len = 3U;
+    // **** 0xdd: get healthpacket and CANPacket version hashes
+    case 0xdd: {
+      uint32_t versions[2] = {HEALTH_PACKET_VERSION, CAN_PACKET_VERSION_HASH};
+      (void)memcpy(resp, (uint8_t *)versions, sizeof(versions));
+      resp_len = sizeof(versions);
       break;
+    }
 
     default:
       // Ignore unhandled requests
diff --git a/board/health.h b/board/health.h
index 60f12460..f585cd63 100644
--- a/board/health.h
+++ b/board/health.h
@@ -1,8 +1,5 @@
 #pragma once
 
-// When changing these structs, python/__init__.py needs to be kept up to date!
-
-#define HEALTH_PACKET_VERSION 18
 struct __attribute__((packed)) health_t {
   uint32_t uptime_pkt;
   uint32_t voltage_pkt;
@@ -32,7 +29,6 @@ struct __attribute__((packed)) health_t {
   uint16_t sound_output_level_pkt;
 };
 
-#define CAN_HEALTH_PACKET_VERSION 5
 typedef struct __attribute__((packed)) {
   uint8_t bus_off;
   uint32_t bus_off_cnt;
diff --git a/board/jungle/__init__.py b/board/jungle/__init__.py
index e9e7e96b..3fe8afd7 100644
--- a/board/jungle/__init__.py
+++ b/board/jungle/__init__.py
@@ -4,7 +4,7 @@ import struct
 from functools import wraps
 
 from panda import Panda, PandaDFU
-from panda.python.constants import McuType
+from panda.python.constants import McuType, compute_version_hash
 
 BASEDIR = os.path.dirname(os.path.realpath(__file__))
 FW_PATH = os.path.join(BASEDIR, "../obj/")
@@ -39,7 +39,7 @@ class PandaJungle(Panda):
   H7_DEVICES = [HW_TYPE_V2, ]
   SUPPORTED_DEVICES = H7_DEVICES
 
-  HEALTH_PACKET_VERSION = 1
+  HEALTH_PACKET_VERSION = compute_version_hash(os.path.join(BASEDIR, "jungle_health.h"))
   HEALTH_STRUCT = struct.Struct("<IffffffHHHHHHHHHHHH")
 
   HARNESS_ORIENTATION_NONE = 0
@@ -108,13 +108,11 @@ class PandaJungle(Panda):
 
   # ******************* control *******************
 
-  # Returns tuple with health packet version and CAN packet/USB packet version
   def get_packets_versions(self):
-    dat = self._handle.controlRead(PandaJungle.REQUEST_IN, 0xdd, 0, 0, 3)
-    if dat and len(dat) == 3:
-      a = struct.unpack("BBB", dat)
-      return (a[0], a[1], a[2])
-    return (-1, -1, -1)
+    dat = self._handle.controlRead(PandaJungle.REQUEST_IN, 0xdd, 0, 0, 8)
+    if dat and len(dat) == 8:
+      return struct.unpack("<II", dat)
+    return (0, 0)
 
   # ******************* jungle stuff *******************
 
diff --git a/board/jungle/jungle_health.h b/board/jungle/jungle_health.h
index 931ed371..96b8a3bf 100644
--- a/board/jungle/jungle_health.h
+++ b/board/jungle/jungle_health.h
@@ -1,6 +1,3 @@
-// When changing these structs, python/__init__.py needs to be kept up to date!
-
-#define JUNGLE_HEALTH_PACKET_VERSION 1
 struct __attribute__((packed)) jungle_health_t {
   uint32_t uptime_pkt;
   float ch1_power;
diff --git a/board/jungle/main_comms.h b/board/jungle/main_comms.h
index b19f799a..290b7c72 100644
--- a/board/jungle/main_comms.h
+++ b/board/jungle/main_comms.h
@@ -180,13 +180,13 @@ int comms_control_handler(ControlPacket_t *req, uint8_t *resp) {
         current_board->set_can_mode(CAN_MODE_NORMAL);
       }
       break;
-    // **** 0xdd: get healthpacket and CANPacket versions
-    case 0xdd:
-      resp[0] = JUNGLE_HEALTH_PACKET_VERSION;
-      resp[1] = CAN_PACKET_VERSION;
-      resp[2] = CAN_HEALTH_PACKET_VERSION;
-      resp_len = 3;
+    // **** 0xdd: get healthpacket and CANPacket version hashes
+    case 0xdd: {
+      uint32_t versions[2] = {JUNGLE_HEALTH_PACKET_VERSION, CAN_PACKET_VERSION_HASH};
+      (void)memcpy(resp, (uint8_t *)versions, sizeof(versions));
+      resp_len = sizeof(versions);
       break;
+    }
     // **** 0xde: set can bitrate
     case 0xde:
       if ((req->param1 < PANDA_CAN_CNT) && is_speed_valid(req->param2, speeds, sizeof(speeds)/sizeof(speeds[0]))) {
diff --git a/board/main_comms.h b/board/main_comms.h
index 0627bf9e..8229a47a 100644
--- a/board/main_comms.h
+++ b/board/main_comms.h
@@ -226,13 +226,13 @@ int comms_control_handler(ControlPacket_t *req, uint8_t *resp) {
     case 0xdc:
       set_safety_mode(req->param1, (uint16_t)req->param2);
       break;
-    // **** 0xdd: get healthpacket and CANPacket versions
-    case 0xdd:
-      resp[0] = HEALTH_PACKET_VERSION;
-      resp[1] = CAN_PACKET_VERSION;
-      resp[2] = CAN_HEALTH_PACKET_VERSION;
-      resp_len = 3;
+    // **** 0xdd: get health and CAN packet versions
+    case 0xdd: {
+      uint32_t versions[2] = {HEALTH_PACKET_VERSION, CAN_PACKET_VERSION_HASH};
+      (void)memcpy(resp, (uint8_t *)versions, sizeof(versions));
+      resp_len = sizeof(versions);
       break;
+    }
     // **** 0xde: set can bitrate
     case 0xde:
       if ((req->param1 < PANDA_CAN_CNT) && is_speed_valid(req->param2, speeds, sizeof(speeds)/sizeof(speeds[0]))) {
diff --git a/pyproject.toml b/pyproject.toml
index bf5418a7..47319524 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -49,6 +49,10 @@ packages = [
   "panda.board.jungle",
 ]
 
+[tool.setuptools.package-data]
+"panda.board" = ["health.h"]
+"panda.board.jungle" = ["jungle_health.h"]
+
 [tool.setuptools.package-dir]
 panda = "."
 
diff --git a/python/__init__.py b/python/__init__.py
index 248d98bb..309c0b85 100644
--- a/python/__init__.py
+++ b/python/__init__.py
@@ -10,10 +10,11 @@ import ctypes
 from functools import wraps, partial
 from itertools import accumulate
 
+import opendbc
 from opendbc.car.structs import CarParams
 
 from .base import BaseHandle
-from .constants import FW_PATH, McuType
+from .constants import BASEDIR, FW_PATH, McuType, compute_version_hash
 from .dfu import PandaDFU
 from .spi import PandaSpiHandle, PandaSpiException, PandaProtocolMismatch
 from .usb import PandaUsbHandle
@@ -104,7 +105,6 @@ def ensure_version(desc, lib_field, panda_field, fn):
     return fn(self, *args, **kwargs)
   return wrapper
 ensure_can_packet_version = partial(ensure_version, "CAN", "CAN_PACKET_VERSION", "can_version")
-ensure_can_health_packet_version = partial(ensure_version, "CAN health", "CAN_HEALTH_PACKET_VERSION", "can_health_version")
 ensure_health_packet_version = partial(ensure_version, "health", "HEALTH_PACKET_VERSION", "health_version")
 
 
@@ -126,9 +126,8 @@ class Panda:
   HW_TYPE_CUATRO = b'\x0a'
   HW_TYPE_BODY = b'\xb1'
 
-  CAN_PACKET_VERSION = 4
-  HEALTH_PACKET_VERSION = 18
-  CAN_HEALTH_PACKET_VERSION = 5
+  CAN_PACKET_VERSION = compute_version_hash(os.path.join(opendbc.INCLUDE_PATH, "opendbc/safety/can.h"))
+  HEALTH_PACKET_VERSION = compute_version_hash(os.path.join(BASEDIR, "board/health.h"))
   HEALTH_STRUCT = struct.Struct("<IIIIIIIIBBBBBHBBBHfBBHHHBH")
   CAN_HEALTH_STRUCT = struct.Struct("<BIBBBBBBBBIIIIIIIHHBBBIIII")
 
@@ -210,7 +209,7 @@ class Panda:
     self._serial = serial
     self._connect_serial = serial
     self._handle_open = True
-    self.health_version, self.can_version, self.can_health_version = self.get_packets_versions()
+    self.health_version, self.can_version = self.get_packets_versions()
     logger.debug("connected")
 
     # disable openpilot's heartbeat checks
@@ -536,7 +535,7 @@ class Panda:
       "sound_output_level": a[25],
     }
 
-  @ensure_can_health_packet_version
+  @ensure_health_packet_version
   def can_health(self, can_number):
     LEC_ERROR_CODE = {
       0: "No error",
@@ -598,14 +597,11 @@ class Panda:
   def get_type(self):
     return self._handle.controlRead(Panda.REQUEST_IN, 0xc1, 0, 0, 0x40)
 
-  # Returns tuple with health packet version and CAN packet/USB packet version
   def get_packets_versions(self):
-    dat = self._handle.controlRead(Panda.REQUEST_IN, 0xdd, 0, 0, 3)
-    if dat and len(dat) == 3:
-      a = struct.unpack("BBB", dat)
-      return (a[0], a[1], a[2])
-    else:
-      return (0, 0, 0)
+    dat = self._handle.controlRead(Panda.REQUEST_IN, 0xdd, 0, 0, 8)
+    if dat and len(dat) == 8:
+      return struct.unpack("<II", dat)
+    return (0, 0)
 
   def is_internal(self):
     return self.get_type() in Panda.INTERNAL_DEVICES
diff --git a/python/constants.py b/python/constants.py
index 5d1457a2..85e8c99c 100644
--- a/python/constants.py
+++ b/python/constants.py
@@ -1,10 +1,15 @@
 import os
 import enum
+import hashlib
 from typing import NamedTuple
 
 BASEDIR = os.path.join(os.path.dirname(os.path.realpath(__file__)), "../")
 FW_PATH = os.path.join(BASEDIR, "board/obj/")
 
+def compute_version_hash(filepath):
+  with open(filepath, "rb") as f:
+    return int.from_bytes(hashlib.sha256(f.read()).digest()[:4], 'little')
+
 USBPACKET_MAX_SIZE = 0x40
 
 class McuConfig(NamedTuple):