From 09ae37313a8b6d567a05a3ae886de78e88cd1afe Mon Sep 17 00:00:00 2001 From: user Date: Fri, 17 Jul 2026 12:39:01 +0200 Subject: net: proper socket API in the kernel (SYS_NET) - no more SLIP in userland The network stack moves into the kernel. src/socket.asm owns SLIP framing, IPv4, RFC1071 checksums, and ICMP; programs now speak a socket API through one syscall (SYS_NET, DE=&netreq dispatched by op): net_socket/connect/send/recv/ close/poll (c/sock.h). No program touches SLIP, IP headers, or checksums. - Socket table (4 sockets) + tx/rx buffers in WRAM0; our IP = 10.0.0.2. - net_pump: drains the link, reassembles SLIP frames, demuxes IPv4. Inbound ICMP echo requests are auto-answered in-kernel, so the GB replies to pings whenever any process pumps RX. - ICMP sockets: send() emits an echo request to the connected peer; recv() returns the matching reply (with a spin/yield timeout). ping.c is now a ~15-line socket client; netd.c is just `for(;;){net_poll(); yield();}`. Verified over tunbridge: /# ping 1.1.1.1 -> replies from the real internet (kernel builds it all) host# ping 10.0.0.2 -> 4/4, 0% loss (kernel auto-answers) Gotchas recorded: gbos.inc isn't a make dep (touch asm after editing); this crt0 doesn't copy initializers (fill arrays at runtime); and the arg string at 0xA000 overlaps _DATA, so parse targets must sit past it (big buffer first). UDP and TCP sockets build on this same core next. --- c/gbos.h | 1 + 1 file changed, 1 insertion(+) (limited to 'c/gbos.h') diff --git a/c/gbos.h b/c/gbos.h index df52fbe..6ecbd4a 100644 --- a/c/gbos.h +++ b/c/gbos.h @@ -17,6 +17,7 @@ void ssend(unsigned char b); /* link-port: transmit one byte */ unsigned char srecv(void); /* link-port: receive one byte (blocks) */ int srecv_nb(void); /* link-port: receive, or -1 if none */ unsigned char pollin(void); /* poll OSK for a typed char, or 0 */ +unsigned char sys_net(void *req); /* socket layer trap (see sock.h) */ /* helpers (c/libc.c) */ void putu(unsigned int n); /* print decimal */ -- cgit v1.3.1-sl0p