From a2cb756693229c7880d926d2cdde2f838c697415 Mon Sep 17 00:00:00 2001 From: user Date: Fri, 17 Jul 2026 14:11:22 +0200 Subject: net: DHCP client - lease the IP at boot instead of hardcoding it The address is no longer baked in. net_init starts at 0.0.0.0; a DHCP client runs as the first thing on boot (init/shell forks it and waits), and only once it has a lease (or gives up) does the prompt appear. Kernel: - IP is configurable: 0.0.0.0 until leased; NET_SETIP op stores it. - 16-bit frame length. DHCP/BOOTP packets are ~272 bytes, over the old 255-byte frame cap, so net_slip_send takes a 16-bit length, net_pump assembles into a 320-byte buffer with a 16-bit wNetRxLen, and udp_send writes a 16-bit IP total. Payloads stay <=255 (kept small on purpose) so the per-protocol datalen math is unchanged. wNetTx/wNetRxBuf 256->320, SK_RXBUF 208->288. Userland: - c/dhcp.c: DISCOVER->OFFER->REQUEST->ACK over a UDP socket, then net_setip(); times out gracefully (shell still boots) if there's no server. sh.c runs it before the prompt. Bridge (self-contained DHCP server, no dnsmasq): - tunbridge.py + netboot intercept UDP->:67 and answer OFFER/ACK leasing 10.0.0.2 (gateway 10.0.0.1); everything else is bridged/NATed as before. Regression-tested ICMP/UDP/TCP after the 16-bit change. Verified end to end: dhcp: discovering dhcp: leased 10.0.0.2 /# ping 10.0.0.1 -> 4/4 (traffic from the leased address) --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Makefile') diff --git a/Makefile b/Makefile index e3bad9d..99160dc 100644 --- a/Makefile +++ b/Makefile @@ -20,7 +20,7 @@ $(BUILD)/%.o: src/%.asm | $(BUILD) # C programs: compiled with SDCC into ROM-bank blobs and INCBIN'd by programs.asm CBLOBS := c/chello.bin c/echo.bin c/true.bin c/false.bin c/uname.bin \ c/pid.bin c/cat.bin c/wc.bin c/head.bin c/args.bin \ - c/ls.bin c/save.bin c/rm.bin c/sh.bin c/ps.bin c/kill.bin c/spin.bin c/blk.bin c/mkdir.bin c/count.bin c/ptest.bin c/necho.bin c/wget.bin c/chat.bin c/netd.bin c/ping.bin c/nslookup.bin + c/ls.bin c/save.bin c/rm.bin c/sh.bin c/ps.bin c/kill.bin c/spin.bin c/blk.bin c/mkdir.bin c/count.bin c/ptest.bin c/necho.bin c/wget.bin c/chat.bin c/netd.bin c/ping.bin c/nslookup.bin c/dhcp.bin $(BUILD)/programs.o: $(CBLOBS) # C programs also depend on the shared libc sources -- cgit v1.3.1-sl0p