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import of dnsmasq-2.32.tar.gz

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This commit is contained in:
Simon Kelley
2006-06-09 21:02:31 +01:00
parent 7cebd20fe7
commit 849a8357ba
24 changed files with 6621 additions and 4429 deletions
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136
src/bpf.c
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@@ -26,17 +26,6 @@ static struct iovec ifreq = {
.iov_len = 0
};
struct header {
struct ether_header ether;
struct ip ip;
struct udphdr {
u16 uh_sport; /* source port */
u16 uh_dport; /* destination port */
u16 uh_ulen; /* udp length */
u16 uh_sum; /* udp checksum */
} udp;
};
void init_bpf(struct daemon *daemon)
{
int i = 0;
@@ -69,9 +58,17 @@ void send_via_bpf(struct daemon *daemon, struct dhcp_packet *mess, size_t len,
Build the packet by steam, and send directly, bypassing
the kernel IP stack */
struct header header;
struct ether_header ether;
struct ip ip;
struct udphdr {
u16 uh_sport; /* source port */
u16 uh_dport; /* destination port */
u16 uh_ulen; /* udp length */
u16 uh_sum; /* udp checksum */
} udp;
u32 i, sum;
struct iovec iov[2];
struct iovec iov[4];
/* Only know how to do ethernet on *BSD */
if (mess->htype != ARPHRD_ETHER || mess->hlen != ETHER_ADDR_LEN)
@@ -85,62 +82,67 @@ void send_via_bpf(struct daemon *daemon, struct dhcp_packet *mess, size_t len,
if (ioctl(daemon->dhcpfd, SIOCGIFADDR, ifr) < 0)
return;
memcpy(header.ether.ether_shost, LLADDR((struct sockaddr_dl *)&ifr->ifr_addr), ETHER_ADDR_LEN);
header.ether.ether_type = htons(ETHERTYPE_IP);
memcpy(ether.ether_shost, LLADDR((struct sockaddr_dl *)&ifr->ifr_addr), ETHER_ADDR_LEN);
ether.ether_type = htons(ETHERTYPE_IP);
if (ntohs(mess->flags) & 0x8000)
{
memset(header.ether.ether_dhost, 255, ETHER_ADDR_LEN);
header.ip.ip_dst.s_addr = INADDR_BROADCAST;
memset(ether.ether_dhost, 255, ETHER_ADDR_LEN);
ip.ip_dst.s_addr = INADDR_BROADCAST;
}
else
{
memcpy(header.ether.ether_dhost, mess->chaddr, ETHER_ADDR_LEN);
header.ip.ip_dst.s_addr = mess->yiaddr.s_addr;
memcpy(ether.ether_dhost, mess->chaddr, ETHER_ADDR_LEN);
ip.ip_dst.s_addr = mess->yiaddr.s_addr;
}
header.ip.ip_p = IPPROTO_UDP;
header.ip.ip_src.s_addr = iface_addr.s_addr;
header.ip.ip_len = htons(sizeof(struct ip) +
sizeof(struct udphdr) +
len) ;
header.ip.ip_hl = sizeof(struct ip) / 4;
header.ip.ip_v = IPVERSION;
header.ip.ip_tos = 0;
header.ip.ip_id = htons(0);
header.ip.ip_off = htons(0x4000); /* don't fragment */
header.ip.ip_ttl = IPDEFTTL;
header.ip.ip_sum = 0;
ip.ip_p = IPPROTO_UDP;
ip.ip_src.s_addr = iface_addr.s_addr;
ip.ip_len = htons(sizeof(struct ip) +
sizeof(struct udphdr) +
len) ;
ip.ip_hl = sizeof(struct ip) / 4;
ip.ip_v = IPVERSION;
ip.ip_tos = 0;
ip.ip_id = htons(0);
ip.ip_off = htons(0x4000); /* don't fragment */
ip.ip_ttl = IPDEFTTL;
ip.ip_sum = 0;
for (sum = 0, i = 0; i < sizeof(struct ip) / 2; i++)
sum += ((u16 *)&header.ip)[i];
sum += ((u16 *)&ip)[i];
while (sum>>16)
sum = (sum & 0xffff) + (sum >> 16);
header.ip.ip_sum = (sum == 0xffff) ? sum : ~sum;
ip.ip_sum = (sum == 0xffff) ? sum : ~sum;
header.udp.uh_sport = htons(DHCP_SERVER_PORT);
header.udp.uh_dport = htons(DHCP_CLIENT_PORT);
udp.uh_sport = htons(DHCP_SERVER_PORT);
udp.uh_dport = htons(DHCP_CLIENT_PORT);
if (len & 1)
((char *)mess)[len] = 0; /* for checksum, in case length is odd. */
header.udp.uh_sum = 0;
header.udp.uh_ulen = sum = htons(sizeof(struct udphdr) + len);
udp.uh_sum = 0;
udp.uh_ulen = sum = htons(sizeof(struct udphdr) + len);
sum += htons(IPPROTO_UDP);
for (i = 0; i < 4; i++)
sum += ((u16 *)&header.ip.ip_src)[i];
sum += ((u16 *)&ip.ip_src)[i];
for (i = 0; i < sizeof(struct udphdr)/2; i++)
sum += ((u16 *)&header.udp)[i];
sum += ((u16 *)&udp)[i];
for (i = 0; i < (len + 1) / 2; i++)
sum += ((u16 *)mess)[i];
while (sum>>16)
sum = (sum & 0xffff) + (sum >> 16);
header.udp.uh_sum = (sum == 0xffff) ? sum : ~sum;
udp.uh_sum = (sum == 0xffff) ? sum : ~sum;
ioctl(daemon->dhcp_raw_fd, BIOCSETIF, ifr);
iov[0].iov_base = &header;
iov[0].iov_len = sizeof(struct header);
iov[1].iov_base = mess;
iov[1].iov_len = len;
while (writev(daemon->dhcp_raw_fd, iov, 2) == -1 && retry_send());
iov[0].iov_base = &ether;
iov[0].iov_len = sizeof(ether);
iov[1].iov_base = &ip;
iov[1].iov_len = sizeof(ip);
iov[2].iov_base = &udp;
iov[2].iov_len = sizeof(udp);
iov[3].iov_base = mess;
iov[3].iov_len = len;
while (writev(daemon->dhcp_raw_fd, iov, 4) == -1 && retry_send());
}
int iface_enumerate(struct daemon *daemon, void *parm, int (*ipv4_callback)(), int (*ipv6_callback)())
@@ -150,31 +152,33 @@ int iface_enumerate(struct daemon *daemon, void *parm, int (*ipv4_callback)(), i
struct ifconf ifc;
int fd, errsav, ret = 0;
int lastlen = 0;
size_t len;
size_t len = 0;
if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
return 0;
for (len = 0; ; len += 10*sizeof(struct ifreq))
while(1)
{
if (!expand_buf(&ifconf, len))
goto err;
ifc.ifc_len = len;
ifc.ifc_buf = ifconf.iov_base;
if (ioctl(fd, SIOCGIFCONF, &ifc) == -1)
{
if (errno != EINVAL || lastlen != 0)
goto err;
}
else
{
if (ifc.ifc_len == lastlen)
break; /* got a big enough buffer now */
lastlen = ifc.ifc_len;
}
}
len += 10*sizeof(struct ifreq);
if (!expand_buf(&ifconf, len))
goto err;
ifc.ifc_len = len;
ifc.ifc_buf = ifconf.iov_base;
if (ioctl(fd, SIOCGIFCONF, &ifc) == -1)
{
if (errno != EINVAL || lastlen != 0)
goto err;
}
else
{
if (ifc.ifc_len == lastlen)
break; /* got a big enough buffer now */
lastlen = ifc.ifc_len;
}
}
for (ptr = ifc.ifc_buf; ptr < ifc.ifc_buf + ifc.ifc_len; ptr += len )
{