From 2d758af9e4ee81fb76ef922d8e91a90f2fcd2e9c Mon Sep 17 00:00:00 2001
From: Astro <astro@spaceboyz.net>
Date: Thu, 21 Mar 2019 17:41:33 +0100
Subject: [PATCH] add feature "generate-hwaddr" to generate indivudal MAC addrs
 from device electronic signature

---
 Cargo.toml  |  3 +++
 src/main.rs | 19 +++++++++++++++++--
 src/net.rs  | 10 ++++------
 3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index f67ed06..555b500 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -32,9 +32,12 @@ stm32f4xx-hal = { git = "https://github.com/stm32-rs/stm32f4xx-hal", features =
 #stm32-eth = { version = "0.1.0", features = ["smoltcp-phy", "nucleo-f429zi"] }
 stm32-eth = { git = "https://github.com/stm32-rs/stm32-eth", features = ["smoltcp-phy", "nucleo-f429zi"] }
 smoltcp = { version = "0.5.0", default-features = false, features = ["proto-ipv4", "socket-tcp", "log"] }
+hash2hwaddr = { version = "0.0", optional = true }
 
 [features]
 semihosting = ["panic-semihosting", "cortex-m-log/semihosting"]
+generate-hwaddr = ["hash2hwaddr"]
+default = ["generate-hwaddr"]
 
 [profile.release]
 codegen-units = 1
diff --git a/src/main.rs b/src/main.rs
index 383457a..45f56d1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -22,7 +22,10 @@ use stm32f4xx_hal::{
     time::U32Ext,
     stm32::{CorePeripherals, Peripherals},
 };
-use smoltcp::time::Instant;
+use smoltcp::{
+    time::Instant,
+    wire::EthernetAddress,
+};
 
 mod adc_input;
 use adc_input::AdcInput;
@@ -39,6 +42,9 @@ use led::Led;
 /// This should be a multiple of the `TIMER_RATE`.
 const OUTPUT_INTERVAL: u32 = 1000;
 
+#[cfg(not(feature = "generate-hwaddr"))]
+const NET_HWADDR: [u8; 6] = [0x02, 0x00, 0xDE, 0xAD, 0xBE, 0xEF];
+
 #[cfg(not(feature = "semihosting"))]
 fn init_log() {}
 
@@ -104,8 +110,17 @@ fn main() -> ! {
     info!("Timer setup");
     timer::setup(cp.SYST, clocks);
 
+    #[cfg(not(feature = "generate-hwaddr"))]
+    let hwaddr = EthernetAddress(NET_HWADDR);
+    #[cfg(feature = "generate-hwaddr")]
+    let hwaddr = {
+        let uid = stm32f4xx_hal::signature::Uid::get();
+        EthernetAddress(hash2hwaddr::generate_hwaddr(uid))
+    };
+    info!("Net hwaddr: {}", hwaddr);
+
     info!("Net startup");
-    net::run(&mut cp.NVIC, dp.ETHERNET_MAC, dp.ETHERNET_DMA, |iface| {
+    net::run(&mut cp.NVIC, dp.ETHERNET_MAC, dp.ETHERNET_DMA, hwaddr, |iface| {
         Server::run(iface, |server| {
             let mut last_output = 0_u32;
             loop {
diff --git a/src/net.rs b/src/net.rs
index 05933e2..be51996 100644
--- a/src/net.rs
+++ b/src/net.rs
@@ -18,16 +18,15 @@ static mut RX_RING: Option<[RingEntry<RxDescriptor>; 8]> = None;
 /// ethernet peripheral cannot access)
 static mut TX_RING: Option<[RingEntry<TxDescriptor>; 2]> = None;
 
-// TODO: generate one from device id
-const SRC_MAC: [u8; 6] = [0x00, 0x00, 0xDE, 0xAD, 0xBE, 0xEF];
-
 /// Interrupt pending flag: set by the `ETH` interrupt handler, should
 /// be cleared before polling the interface.
 static NET_PENDING: Mutex<RefCell<bool>> = Mutex::new(RefCell::new(false));
 
 /// Run callback `f` with ethernet driver and TCP/IP stack
-pub fn run<F>(nvic: &mut NVIC, ethernet_mac: ETHERNET_MAC, ethernet_dma: ETHERNET_DMA, f: F)
-where
+pub fn run<F>(
+    nvic: &mut NVIC, ethernet_mac: ETHERNET_MAC, ethernet_dma: ETHERNET_DMA,
+    ethernet_addr: EthernetAddress, f: F
+) where
     F: FnOnce(EthernetInterface<&mut stm32_eth::Eth<'static, 'static>>),
 {
     let rx_ring = unsafe {
@@ -48,7 +47,6 @@ where
     let mut ip_addrs = [IpCidr::new(local_addr, 24)];
     let mut neighbor_storage = [None; 16];
     let neighbor_cache = NeighborCache::new(&mut neighbor_storage[..]);
-    let ethernet_addr = EthernetAddress(SRC_MAC);
     let iface = EthernetInterfaceBuilder::new(&mut eth_dev)
         .ethernet_addr(ethernet_addr)
         .ip_addrs(&mut ip_addrs[..])