static void bootp_reply(struct bootp_t *bp) { BOOTPClient *bc; struct mbuf *m; struct bootp_t *rbp; struct sockaddr_in saddr, daddr; struct in_addr dns_addr; int dhcp_msg_type, val; uint8_t *q; /* extract exact DHCP msg type */ dhcp_decode(bp->bp_vend, DHCP_OPT_LEN, &dhcp_msg_type); dprintf("bootp packet op=%d msgtype=%d\n", bp->bp_op, dhcp_msg_type); if (dhcp_msg_type == 0) dhcp_msg_type = DHCPREQUEST; /* Force reply for old BOOTP clients */ if (dhcp_msg_type != DHCPDISCOVER && dhcp_msg_type != DHCPREQUEST) return; /* XXX: this is a hack to get the client mac address */ memcpy(client_ethaddr, bp->bp_hwaddr, 6); if ((m = m_get()) == NULL) return; m->m_data += IF_MAXLINKHDR; rbp = (struct bootp_t *)m->m_data; m->m_data += sizeof(struct udpiphdr); memset(rbp, 0, sizeof(struct bootp_t)); if (dhcp_msg_type == DHCPDISCOVER) { new_addr: bc = get_new_addr(&daddr.sin_addr); if (!bc) { dprintf("no address left\n"); return; } memcpy(bc->macaddr, client_ethaddr, 6); } else { bc = find_addr(&daddr.sin_addr, bp->bp_hwaddr); if (!bc) { /* if never assigned, behaves as if it was already assigned (windows fix because it remembers its address) */ goto new_addr; } } if (bootp_filename) snprintf((char *)rbp->bp_file, sizeof(rbp->bp_file), "%s", bootp_filename); dprintf("offered addr=%08x\n", ntohl(daddr.sin_addr.s_addr)); saddr.sin_addr.s_addr = htonl(ntohl(special_addr.s_addr) | CTL_ALIAS); saddr.sin_port = htons(BOOTP_SERVER); daddr.sin_port = htons(BOOTP_CLIENT); rbp->bp_op = BOOTP_REPLY; rbp->bp_xid = bp->bp_xid; rbp->bp_htype = 1; rbp->bp_hlen = 6; memcpy(rbp->bp_hwaddr, bp->bp_hwaddr, 6); rbp->bp_yiaddr = daddr.sin_addr; /* Client IP address */ rbp->bp_siaddr = saddr.sin_addr; /* Server IP address */ daddr.sin_addr.s_addr = 0xffffffffu; q = rbp->bp_vend; memcpy(q, rfc1533_cookie, 4); q += 4; if (dhcp_msg_type == DHCPDISCOVER) { *q++ = RFC2132_MSG_TYPE; *q++ = 1; *q++ = DHCPOFFER; } else if (dhcp_msg_type == DHCPREQUEST) { *q++ = RFC2132_MSG_TYPE; *q++ = 1; *q++ = DHCPACK; } if (dhcp_msg_type == DHCPDISCOVER || dhcp_msg_type == DHCPREQUEST) { *q++ = RFC2132_SRV_ID; *q++ = 4; memcpy(q, &saddr.sin_addr, 4); q += 4; *q++ = RFC1533_NETMASK; *q++ = 4; *q++ = 0xff; *q++ = 0xff; *q++ = 0xff; *q++ = 0x00; if (!slirp_restrict) { *q++ = RFC1533_GATEWAY; *q++ = 4; memcpy(q, &saddr.sin_addr, 4); q += 4; *q++ = RFC1533_DNS; *q++ = 4; dns_addr.s_addr = htonl(ntohl(special_addr.s_addr) | CTL_DNS); memcpy(q, &dns_addr, 4); q += 4; } *q++ = RFC2132_LEASE_TIME; *q++ = 4; val = htonl(LEASE_TIME); memcpy(q, &val, 4); q += 4; if (*slirp_hostname) { val = strlen(slirp_hostname); *q++ = RFC1533_HOSTNAME; *q++ = val; memcpy(q, slirp_hostname, val); q += val; } } *q++ = RFC1533_END; m->m_len = sizeof(struct bootp_t) - sizeof(struct ip) - sizeof(struct udphdr); udp_output2(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY); }