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refactor: Reduce setsockopt() calls to improve performance #2

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Merged
MikeWang000000 merged 1 commit into from
Jul 29, 2025
Merged

refactor: Reduce setsockopt() calls to improve performance #2

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86 changes: 60 additions & 26 deletions src/rawsend.c
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Original file line number Diff line number Diff line change
Expand Up @@ -47,7 +47,9 @@ static uint8_t *payload = NULL;
static size_t payload_len = 0;
static int sockfd = -1;
static int sock4fd = -1;
static int sock4if = -1;
static int sock6fd = -1;
static int sock6if = -1;

void fs_rawsend_cleanup(void);

Expand Down Expand Up @@ -108,52 +110,84 @@ static void ipaddr_to_str(struct sockaddr *addr, char ipstr[INET6_ADDRSTRLEN])
}


static int sendto_snat(struct sockaddr_ll *sll, struct sockaddr *daddr,
uint8_t *pkt_buff, int pkt_len)
static int bind_iface(int fd, int ifindex)
{
static int use_bindtoifindex = 1;

int res;
ssize_t nbytes;
char *iface, iface_buf[IF_NAMESIZE];

iface = if_indextoname(sll->sll_ifindex, iface_buf);
if (use_bindtoifindex) {
res = setsockopt(fd, SOL_SOCKET, SO_BINDTOIFINDEX, &ifindex,
sizeof(ifindex));
if (res < 0 && errno == ENOPROTOOPT) {
use_bindtoifindex = 0;
} else if (res < 0) {
E("ERROR: setsockopt(): SO_BINDTOIFINDEX: %s", strerror(errno));
return -1;
} else {
return 0;
}
}

iface = if_indextoname(ifindex, iface_buf);
if (!iface) {
E("ERROR: if_indextoname(): %s", strerror(errno));
return -1;
}

res = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, iface, strlen(iface));
if (res < 0) {
E("ERROR: setsockopt(): SO_BINDTODEVICE: %s", strerror(errno));
return -1;
}

return 0;
}


static int sendto_snat(struct sockaddr_ll *sll, struct sockaddr *daddr,
uint8_t *pkt_buff, int pkt_len)
{
int res, fd;
size_t daddrlen;
ssize_t nbytes;

if (daddr->sa_family == AF_INET) {
res = setsockopt(sock4fd, SOL_SOCKET, SO_BINDTODEVICE, iface,
strlen(iface));
if (res < 0) {
E("ERROR: setsockopt(): SO_BINDTODEVICE: %s", strerror(errno));
return -1;
}
daddrlen = sizeof(struct sockaddr_in);
fd = sock4fd;

nbytes = sendto(sock4fd, pkt_buff, pkt_len, 0, daddr,
sizeof(struct sockaddr_in));
if (nbytes < 0 && errno != EPERM) {
E("ERROR: sendto(): %s", strerror(errno));
return -1;
if (sll->sll_ifindex != sock4if) {
res = bind_iface(fd, sll->sll_ifindex);
if (res < 0) {
E(T(bind_iface));
return -1;
}
sock4if = sll->sll_ifindex;
}
} else if (daddr->sa_family == AF_INET6) {
res = setsockopt(sock6fd, SOL_SOCKET, SO_BINDTODEVICE, iface,
strlen(iface));
if (res < 0) {
E("ERROR: setsockopt(): SO_BINDTODEVICE: %s", strerror(errno));
return -1;
}
daddrlen = sizeof(struct sockaddr_in6);
fd = sock6fd;

nbytes = sendto(sock6fd, pkt_buff, pkt_len, 0, daddr,
sizeof(struct sockaddr_in6));
if (nbytes < 0 && errno != EPERM) {
E("ERROR: sendto(): %s", strerror(errno));
return -1;
if (sll->sll_ifindex != sock6if) {
res = bind_iface(fd, sll->sll_ifindex);
if (res < 0) {
E(T(bind_iface));
return -1;
}
sock6if = sll->sll_ifindex;
}
} else {
E("ERROR: Unknown sa_family: %d", (int) daddr->sa_family);
return -1;
}

nbytes = sendto(fd, pkt_buff, pkt_len, 0, daddr, daddrlen);
if (nbytes < 0 && errno != EPERM) {
E("ERROR: sendto(): %s", strerror(errno));
return -1;
}

return 0;
}

Expand Down