int udp_output_(struct socket *so, struct mbuf *m,
SockAddress* from)
{
SockAddress saddr, daddr;
uint32_t saddr_ip;
uint16_t saddr_port;
saddr_ip = sock_address_get_ip(from);
saddr_port = sock_address_get_port(from);
if ((so->so_faddr_ip & 0xffffff00) == special_addr_ip) {
saddr_ip = so->so_faddr_ip;
if ((so->so_faddr_ip & 0x000000ff) == 0xff)
saddr_ip = alias_addr_ip;
}
sock_address_init_inet( &saddr, saddr_ip, saddr_port );
sock_address_init_inet( &daddr, so->so_laddr_ip, so->so_laddr_port );
return udp_output2_(so, m, &saddr, &daddr, so->so_iptos);
}
static void bootp_reply(const struct bootp_t *bp)
{
BOOTPClient *bc = NULL;
struct mbuf *m;
struct bootp_t *rbp;
SockAddress saddr, daddr;
uint32_t dns_addr;
const ipaddr_t *preq_addr;
int dhcp_msg_type, val;
uint8_t *q;
/* extract exact DHCP msg type */
dhcp_decode(bp, &dhcp_msg_type, &preq_addr);
dprintf("bootp packet op=%d msgtype=%d", bp->bp_op, dhcp_msg_type);
if (preq_addr) {
dprintf(" req_addr=%08x\n", ntohl(*(uint32_t*)preq_addr));
} else {
dprintf("\n");
}
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) {
if (preq_addr) {
bc = request_addr(preq_addr, client_ethaddr);
if (bc) {
sock_address_init_inet(&daddr, ip_geth(*preq_addr), BOOTP_CLIENT);
}
}
if (!bc) {
new_addr:
bc = get_new_addr(&daddr, client_ethaddr);
if (!bc) {
dprintf("no address left\n");
return;
}
}
memcpy(bc->macaddr, client_ethaddr, 6);
} else if (preq_addr) {
bc = request_addr(preq_addr, client_ethaddr);
if (bc) {
sock_address_init_inet(&daddr, ip_geth(*preq_addr), BOOTP_CLIENT);
memcpy(bc->macaddr, client_ethaddr, 6);
} else {
sock_address_init_inet(&daddr, 0, BOOTP_CLIENT);
}
} else {
bc = find_addr(&daddr, 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;
}
}
sock_address_init_inet( &saddr, special_addr_ip | CTL_ALIAS,
BOOTP_SERVER );
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 = htonl(sock_address_get_ip(&daddr)); /* Client IP address */
rbp->bp_siaddr = htonl(sock_address_get_ip(&saddr)); /* Server IP address */
q = rbp->bp_vend;
memcpy(q, rfc1533_cookie, 4);
q += 4;
if (bc) {
uint32_t saddr_ip = htonl(sock_address_get_ip(&saddr));
dprintf("%s addr=%08x\n",
(dhcp_msg_type == DHCPDISCOVER) ? "offered" : "ack'ed",
sock_address_get_ip(&daddr));
if (dhcp_msg_type == DHCPDISCOVER) {
*q++ = RFC2132_MSG_TYPE;
*q++ = 1;
*q++ = DHCPOFFER;
} else /* DHCPREQUEST */ {
*q++ = RFC2132_MSG_TYPE;
*q++ = 1;
*q++ = DHCPACK;
}
if (bootp_filename)
snprintf((char *)rbp->bp_file, sizeof(rbp->bp_file), "%s",
bootp_filename);
*q++ = RFC2132_SRV_ID;
*q++ = 4;
memcpy(q, &saddr_ip, 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_ip, 4);
q += 4;
*q++ = RFC1533_DNS;
*q++ = 4;
dns_addr = htonl(special_addr_ip | 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;
}
} else {
static const char nak_msg[] = "requested address not available";
dprintf("nak'ed addr=%08x\n", ip_geth(*preq_addr));
*q++ = RFC2132_MSG_TYPE;
*q++ = 1;
*q++ = DHCPNAK;
*q++ = RFC2132_MESSAGE;
*q++ = sizeof(nak_msg) - 1;
memcpy(q, nak_msg, sizeof(nak_msg) - 1);
q += sizeof(nak_msg) - 1;
}
*q++ = RFC1533_END;
sock_address_init_inet(&daddr, 0xffffffffu, BOOTP_CLIENT);
m->m_len = sizeof(struct bootp_t) -
sizeof(struct ip) - sizeof(struct udphdr);
udp_output2_(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY);
}
