diff options
| -rw-r--r-- | dhcp.c | 12 | ||||
| -rw-r--r-- | ip.h | 3 |
2 files changed, 13 insertions, 2 deletions
@@ -112,6 +112,8 @@ struct msg { uint32_t xid; uint16_t secs; uint16_t flags; +#define FLAG_BROADCAST htons_constant(0x8000) + uint32_t ciaddr; struct in_addr yiaddr; uint32_t siaddr; @@ -285,10 +287,10 @@ int dhcp(const struct ctx *c, const struct pool *p) { size_t mlen, dlen, offset = 0, opt_len, opt_off = 0; char macstr[ETH_ADDRSTRLEN]; + struct in_addr mask, dst; const struct ethhdr *eh; const struct iphdr *iph; const struct udphdr *uh; - struct in_addr mask; unsigned int i; struct msg *m; @@ -400,7 +402,13 @@ int dhcp(const struct ctx *c, const struct pool *p) opt_set_dns_search(c, sizeof(m->o)); dlen = offsetof(struct msg, o) + fill(m); - tap_udp4_send(c, c->ip4.our_tap_addr, 67, c->ip4.addr, 68, m, dlen); + + if (m->flags & FLAG_BROADCAST) + dst = in4addr_broadcast; + else + dst = c->ip4.addr; + + tap_udp4_send(c, c->ip4.our_tap_addr, 67, dst, 68, m, dlen); return 1; } @@ -101,4 +101,7 @@ static const struct in6_addr in6addr_ll_all_nodes = { }, }; +/* IPv4 Limited Broadcast (RFC 919, Section 7), 255.255.255.255 */ +static const struct in_addr in4addr_broadcast = { 0xffffffff }; + #endif /* IP_H */ |