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authoruser <user@clank>2026-07-18 00:38:38 +0200
committeruser <user@clank>2026-07-18 00:38:38 +0200
commitba2d7ae1d7b319645b10aaa31a7f664f9f80c25c (patch)
treee01e6c7c710a661defe2515ff9657f08cddcb283 /c/dhcp.c
parenttools: gbtype prints hub errors to stderr and exits 1 (diff)
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refactor: c/ -> usr/, compiled program blobs out of the source tree
Userland sources live in usr/ (fits the Unix theme better than 'c'). SDCC output .bin blobs land in build/usr/ with the other build artifacts instead of littering the source dir; programs.asm INCBINs them from there. Byte-identical ROM.
Diffstat (limited to 'c/dhcp.c')
-rw-r--r--c/dhcp.c72
1 files changed, 0 insertions, 72 deletions
diff --git a/c/dhcp.c b/c/dhcp.c
deleted file mode 100644
index e4186f4..0000000
--- a/c/dhcp.c
+++ /dev/null
@@ -1,72 +0,0 @@
-#include "sock.h"
-/* dhcp - a minimal DHCP client. DISCOVER -> OFFER -> REQUEST -> ACK over UDP
- (kernel owns UDP; this owns BOOTP/DHCP), then hands the leased address to the
- kernel with net_setip(). Run at boot before the shell. Times out gracefully
- if there's no server (the shell then comes up unconfigured). */
-
-static unsigned char pkt[288]; /* BOOTP is ~240B + options (frames > 255) */
-static unsigned char ip[4];
-static unsigned char bcast[4];
-
-/* fill the fixed BOOTP request header + magic cookie; options start at 240 */
-static void bootp(void) {
- unsigned int i;
- for (i = 0; i < 240; i++) pkt[i] = 0;
- pkt[0] = 1; pkt[1] = 1; pkt[2] = 6; /* op=request htype=eth hlen=6 */
- pkt[4] = 0x12; pkt[5] = 0x34; pkt[6] = 0x56; pkt[7] = 0x78; /* xid */
- pkt[10] = 0x80; /* flags: broadcast reply */
- pkt[28] = 0x02; pkt[29] = 0x47; pkt[30] = 0x42; pkt[33] = 0x01; /* client MAC */
- pkt[236] = 0x63; pkt[237] = 0x82; pkt[238] = 0x53; pkt[239] = 0x63; /* magic */
-}
-
-/* DHCP message type from the received packet (option 53), or 0 */
-static unsigned char mtype(void) {
- unsigned int p = 240;
- while (p < 280 && pkt[p] != 255) {
- if (pkt[p] == 0) { p++; continue; } /* pad */
- if (pkt[p] == 53) return pkt[p + 2];
- p += 2 + pkt[p + 1];
- }
- return 0;
-}
-
-void main(void) {
- unsigned char s, i, n;
- unsigned int p;
- bcast[0] = 255; bcast[1] = 255; bcast[2] = 255; bcast[3] = 255;
-
- puts("dhcp: discovering"); nl();
- s = net_socket(SOCK_UDP);
- if (s == 0xFF) { puts("dhcp: no socket"); nl(); return; }
- net_bind(s, 68);
- net_connect(s, bcast, 67);
-
- /* DISCOVER -> OFFER (retry a few times for startup timing) */
- bootp();
- p = 240;
- pkt[p++] = 53; pkt[p++] = 1; pkt[p++] = 1; /* DHCPDISCOVER */
- pkt[p++] = 255;
- n = 0xFF;
- for (i = 0; i < 3 && n == 0xFF; i++) {
- net_send(s, pkt, (unsigned char)p);
- n = net_recv(s, pkt, 255);
- }
- if (n == 0xFF || mtype() != 2) { puts("dhcp: no offer"); nl(); net_close(s); return; }
- ip[0] = pkt[16]; ip[1] = pkt[17]; ip[2] = pkt[18]; ip[3] = pkt[19]; /* yiaddr */
-
- /* REQUEST -> ACK */
- bootp();
- p = 240;
- pkt[p++] = 53; pkt[p++] = 1; pkt[p++] = 3; /* DHCPREQUEST */
- pkt[p++] = 50; pkt[p++] = 4; /* requested IP */
- pkt[p++] = ip[0]; pkt[p++] = ip[1]; pkt[p++] = ip[2]; pkt[p++] = ip[3];
- pkt[p++] = 255;
- net_send(s, pkt, (unsigned char)p);
- n = net_recv(s, pkt, 255);
- net_close(s);
- if (n == 0xFF || mtype() != 5) { puts("dhcp: request failed"); nl(); return; }
- ip[0] = pkt[16]; ip[1] = pkt[17]; ip[2] = pkt[18]; ip[3] = pkt[19];
-
- net_setip(ip);
- puts("dhcp: leased "); for (i = 0; i < 4; i++) { putu(ip[i]); if (i < 3) putc('.'); } nl();
-}