mirror of
https://github.com/cesanta/mongoose.git
synced 2025-08-06 13:37:34 +08:00
Handle TCP options
This commit is contained in:
Sergio R. Caprile
parent
bd53529b45
commit
1ef6c6aeb5
69
mongoose.c
69
mongoose.c
@ -4178,11 +4178,12 @@ void mg_mgr_init(struct mg_mgr *mgr) {
|
||||
|
||||
struct connstate {
|
||||
uint32_t seq, ack; // TCP seq/ack counters
|
||||
uint64_t timer; // TCP keep-alive / ACK timer
|
||||
uint64_t timer; // TCP timer (see 'ttype' below)
|
||||
uint32_t acked; // Last ACK-ed number
|
||||
size_t unacked; // Not acked bytes
|
||||
uint16_t dmss; // destination MSS (from TCP opts)
|
||||
uint8_t mac[6]; // Peer MAC address
|
||||
uint8_t ttype; // Timer type. 0: ack, 1: keep-alive
|
||||
uint8_t ttype; // Timer type:
|
||||
#define MIP_TTYPE_KEEPALIVE 0 // Connection is idle for long, send keepalive
|
||||
#define MIP_TTYPE_ACK 1 // Peer sent us data, we have to ack it soon
|
||||
#define MIP_TTYPE_ARP 2 // ARP resolve sent, waiting for response
|
||||
@ -4686,17 +4687,17 @@ static void rx_udp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *dst_mac, uint32_t dst_ip,
|
||||
uint8_t flags, uint16_t sport, uint16_t dport,
|
||||
uint32_t seq, uint32_t ack, const void *buf, size_t len) {
|
||||
#if 0
|
||||
uint8_t opts[] = {2, 4, 5, 0xb4, 4, 2, 0, 0}; // MSS = 1460, SACK permitted
|
||||
if (flags & TH_SYN) {
|
||||
// Handshake? Set MSS
|
||||
struct ip *ip;
|
||||
struct tcp *tcp;
|
||||
uint16_t opts[4 / 2];
|
||||
if (flags & TH_SYN) { // Send MSS, RFC-9293 3.7.1
|
||||
opts[0] = mg_htons(0x0204); // RFC-9293 3.2
|
||||
opts[1] = mg_htons(ifp->mtu - 40); // RFC-6691
|
||||
buf = opts;
|
||||
len = sizeof(opts);
|
||||
}
|
||||
#endif
|
||||
struct ip *ip =
|
||||
tx_ip(ifp, dst_mac, 6, ifp->ip, dst_ip, sizeof(struct tcp) + len);
|
||||
struct tcp *tcp = (struct tcp *) (ip + 1);
|
||||
ip = tx_ip(ifp, dst_mac, 6, ifp->ip, dst_ip, sizeof(struct tcp) + len);
|
||||
tcp = (struct tcp *) (ip + 1);
|
||||
memset(tcp, 0, sizeof(*tcp));
|
||||
if (buf != NULL && len) memmove(tcp + 1, buf, len);
|
||||
tcp->sport = sport;
|
||||
@ -4706,7 +4707,7 @@ static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *dst_mac, uint32_t dst_ip,
|
||||
tcp->flags = flags;
|
||||
tcp->win = mg_htons(MIP_TCP_WIN);
|
||||
tcp->off = (uint8_t) (sizeof(*tcp) / 4 << 4);
|
||||
// if (flags & TH_SYN) tcp->off = 0x70; // Handshake? header size 28 bytes
|
||||
if (flags & TH_SYN) tcp->off += (uint8_t) (sizeof(opts) / 4 << 4);
|
||||
|
||||
uint32_t cs = 0;
|
||||
uint16_t n = (uint16_t) (sizeof(*tcp) + len);
|
||||
@ -4740,6 +4741,7 @@ static struct mg_connection *accept_conn(struct mg_connection *lsn,
|
||||
return NULL;
|
||||
}
|
||||
struct connstate *s = (struct connstate *) (c + 1);
|
||||
s->dmss = 536; // assume default, RFC-9293 3.7.1
|
||||
s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq);
|
||||
memcpy(s->mac, pkt->eth->src, sizeof(s->mac));
|
||||
settmout(c, MIP_TTYPE_KEEPALIVE);
|
||||
@ -4793,10 +4795,11 @@ long mg_io_send(struct mg_connection *c, const void *buf, size_t len) {
|
||||
len = trim_len(c, len);
|
||||
if (c->is_udp) {
|
||||
tx_udp(ifp, s->mac, ifp->ip, c->loc.port, dst_ip, c->rem.port, buf, len);
|
||||
} else {
|
||||
size_t sent =
|
||||
tx_tcp(ifp, s->mac, dst_ip, TH_PUSH | TH_ACK, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), buf, len);
|
||||
} else { // TCP, cap to peer's MSS
|
||||
size_t sent;
|
||||
if (len > s->dmss) len = s->dmss; // RFC-6691: reduce if sending opts
|
||||
sent = tx_tcp(ifp, s->mac, dst_ip, TH_PUSH | TH_ACK, c->loc.port,
|
||||
c->rem.port, mg_htonl(s->seq), mg_htonl(s->ack), buf, len);
|
||||
if (sent == 0) {
|
||||
return MG_IO_WAIT;
|
||||
} else if (sent == (size_t) -1) {
|
||||
@ -4856,10 +4859,10 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
}
|
||||
tx_tcp(c->mgr->ifp, s->mac, rem_ip, flags, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
|
||||
if (pkt->pay.len == 0) return; // if no data, we're done
|
||||
} else if (pkt->pay.len == 0) { // this is an ACK
|
||||
if (pkt->pay.len == 0) return; // if no data, we're done
|
||||
} else if (pkt->pay.len == 0) { // this is an ACK
|
||||
if (s->fin_rcvd && s->ttype == MIP_TTYPE_FIN) s->twclosure = true;
|
||||
return; // no data to process
|
||||
return; // no data to process
|
||||
} else if (seq != s->ack) {
|
||||
uint32_t ack = (uint32_t) (mg_htonl(pkt->tcp->seq) + pkt->pay.len);
|
||||
if (s->ack == ack) {
|
||||
@ -4869,11 +4872,11 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
tx_tcp(c->mgr->ifp, s->mac, rem_ip, TH_ACK, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
|
||||
}
|
||||
return; // drop it
|
||||
return; // drop it
|
||||
} else if (io->size - io->len < pkt->pay.len &&
|
||||
!mg_iobuf_resize(io, io->len + pkt->pay.len)) {
|
||||
mg_error(c, "oom");
|
||||
return; // drop it
|
||||
return; // drop it
|
||||
}
|
||||
// Copy TCP payload into the IO buffer. If the connection is plain text,
|
||||
// we copy to c->recv. If the connection is TLS, this data is encrypted,
|
||||
@ -4909,6 +4912,25 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
}
|
||||
}
|
||||
|
||||
// process options (MSS)
|
||||
static void handle_opt(struct connstate *s, struct tcp *tcp) {
|
||||
uint8_t *opts = (uint8_t *) (tcp + 1);
|
||||
int len = 4 * ((int) (tcp->off >> 4) - (sizeof(*tcp) / 4));
|
||||
s->dmss = 536; // assume default, RFC-9293 3.7.1
|
||||
while (len > 0) { // RFC-9293 3.1 3.2
|
||||
uint8_t kind = opts[0], optlen = 1;
|
||||
if (kind != 1) { // No-Operation
|
||||
if (kind == 0) break; // End of Option List
|
||||
optlen = opts[1];
|
||||
if (kind == 2 && optlen == 4) // set received MSS
|
||||
s->dmss = (uint16_t) (((uint16_t) opts[2] << 8) + opts[3]);
|
||||
}
|
||||
MG_INFO(("kind: %u, optlen: %u, len: %d\n", kind, optlen, len));
|
||||
opts += optlen;
|
||||
len -= optlen;
|
||||
}
|
||||
}
|
||||
|
||||
static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
struct mg_connection *c = getpeer(ifp->mgr, pkt, false);
|
||||
struct connstate *s = c == NULL ? NULL : (struct connstate *) (c + 1);
|
||||
@ -4916,6 +4938,7 @@ static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
MG_INFO(("%lu %hhu %d", c ? c->id : 0, pkt->tcp->flags, (int) pkt->pay.len));
|
||||
#endif
|
||||
if (c != NULL && c->is_connecting && pkt->tcp->flags == (TH_SYN | TH_ACK)) {
|
||||
handle_opt(s, pkt->tcp); // process options (MSS)
|
||||
s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq) + 1;
|
||||
tx_tcp_pkt(ifp, pkt, TH_ACK, pkt->tcp->ack, NULL, 0);
|
||||
c->is_connecting = 0; // Client connected
|
||||
@ -4945,6 +4968,8 @@ static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
if (c->is_accepted) mg_error(c, "peer RST"); // RFC-1122 4.2.2.13
|
||||
// ignore RST if not connected
|
||||
} else if (pkt->tcp->flags & TH_SYN) {
|
||||
// TODO(): handle_opt(s, pkt->tcp); // process options (MSS)
|
||||
// At this point, s = NULL, there is no connection.
|
||||
// Use peer's source port as ISN, in order to recognise the handshake
|
||||
uint32_t isn = mg_htonl((uint32_t) mg_ntohs(pkt->tcp->sport));
|
||||
tx_tcp_pkt(ifp, pkt, TH_SYN | TH_ACK, isn, NULL, 0);
|
||||
@ -5200,7 +5225,7 @@ void mg_tcpip_init(struct mg_mgr *mgr, struct mg_tcpip_if *ifp) {
|
||||
MG_INFO(("MAC not set. Generated random: %M", mg_print_mac, ifp->mac));
|
||||
}
|
||||
|
||||
// Uf DHCP name is not set, use "mip"
|
||||
// If DHCP name is not set, use "mip"
|
||||
if (ifp->dhcp_name[0] == '\0') {
|
||||
memcpy(ifp->dhcp_name, "mip", 4);
|
||||
}
|
||||
@ -5390,7 +5415,7 @@ bool mg_send(struct mg_connection *c, const void *buf, size_t len) {
|
||||
|
||||
uint8_t mcast_addr[6] = {0x01, 0x00, 0x5e, 0x00, 0x00, 0xfb};
|
||||
void mg_multicast_add(struct mg_connection *c, char *ip) {
|
||||
(void) ip; // ip4_mcastmac(mcast_mac, &ip);
|
||||
(void) ip; // ip4_mcastmac(mcast_mac, &ip);
|
||||
// TODO(): actual IP -> MAC; check database, update
|
||||
c->mgr->ifp->update_mac_hash_table = true; // mark dirty
|
||||
}
|
||||
|
||||
@ -16,11 +16,12 @@
|
||||
|
||||
struct connstate {
|
||||
uint32_t seq, ack; // TCP seq/ack counters
|
||||
uint64_t timer; // TCP keep-alive / ACK timer
|
||||
uint64_t timer; // TCP timer (see 'ttype' below)
|
||||
uint32_t acked; // Last ACK-ed number
|
||||
size_t unacked; // Not acked bytes
|
||||
uint16_t dmss; // destination MSS (from TCP opts)
|
||||
uint8_t mac[6]; // Peer MAC address
|
||||
uint8_t ttype; // Timer type. 0: ack, 1: keep-alive
|
||||
uint8_t ttype; // Timer type:
|
||||
#define MIP_TTYPE_KEEPALIVE 0 // Connection is idle for long, send keepalive
|
||||
#define MIP_TTYPE_ACK 1 // Peer sent us data, we have to ack it soon
|
||||
#define MIP_TTYPE_ARP 2 // ARP resolve sent, waiting for response
|
||||
@ -524,17 +525,17 @@ static void rx_udp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *dst_mac, uint32_t dst_ip,
|
||||
uint8_t flags, uint16_t sport, uint16_t dport,
|
||||
uint32_t seq, uint32_t ack, const void *buf, size_t len) {
|
||||
#if 0
|
||||
uint8_t opts[] = {2, 4, 5, 0xb4, 4, 2, 0, 0}; // MSS = 1460, SACK permitted
|
||||
if (flags & TH_SYN) {
|
||||
// Handshake? Set MSS
|
||||
struct ip *ip;
|
||||
struct tcp *tcp;
|
||||
uint16_t opts[4 / 2];
|
||||
if (flags & TH_SYN) { // Send MSS, RFC-9293 3.7.1
|
||||
opts[0] = mg_htons(0x0204); // RFC-9293 3.2
|
||||
opts[1] = mg_htons(ifp->mtu - 40); // RFC-6691
|
||||
buf = opts;
|
||||
len = sizeof(opts);
|
||||
}
|
||||
#endif
|
||||
struct ip *ip =
|
||||
tx_ip(ifp, dst_mac, 6, ifp->ip, dst_ip, sizeof(struct tcp) + len);
|
||||
struct tcp *tcp = (struct tcp *) (ip + 1);
|
||||
ip = tx_ip(ifp, dst_mac, 6, ifp->ip, dst_ip, sizeof(struct tcp) + len);
|
||||
tcp = (struct tcp *) (ip + 1);
|
||||
memset(tcp, 0, sizeof(*tcp));
|
||||
if (buf != NULL && len) memmove(tcp + 1, buf, len);
|
||||
tcp->sport = sport;
|
||||
@ -544,7 +545,7 @@ static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *dst_mac, uint32_t dst_ip,
|
||||
tcp->flags = flags;
|
||||
tcp->win = mg_htons(MIP_TCP_WIN);
|
||||
tcp->off = (uint8_t) (sizeof(*tcp) / 4 << 4);
|
||||
// if (flags & TH_SYN) tcp->off = 0x70; // Handshake? header size 28 bytes
|
||||
if (flags & TH_SYN) tcp->off += (uint8_t) (sizeof(opts) / 4 << 4);
|
||||
|
||||
uint32_t cs = 0;
|
||||
uint16_t n = (uint16_t) (sizeof(*tcp) + len);
|
||||
@ -578,6 +579,7 @@ static struct mg_connection *accept_conn(struct mg_connection *lsn,
|
||||
return NULL;
|
||||
}
|
||||
struct connstate *s = (struct connstate *) (c + 1);
|
||||
s->dmss = 536; // assume default, RFC-9293 3.7.1
|
||||
s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq);
|
||||
memcpy(s->mac, pkt->eth->src, sizeof(s->mac));
|
||||
settmout(c, MIP_TTYPE_KEEPALIVE);
|
||||
@ -631,10 +633,11 @@ long mg_io_send(struct mg_connection *c, const void *buf, size_t len) {
|
||||
len = trim_len(c, len);
|
||||
if (c->is_udp) {
|
||||
tx_udp(ifp, s->mac, ifp->ip, c->loc.port, dst_ip, c->rem.port, buf, len);
|
||||
} else {
|
||||
size_t sent =
|
||||
tx_tcp(ifp, s->mac, dst_ip, TH_PUSH | TH_ACK, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), buf, len);
|
||||
} else { // TCP, cap to peer's MSS
|
||||
size_t sent;
|
||||
if (len > s->dmss) len = s->dmss; // RFC-6691: reduce if sending opts
|
||||
sent = tx_tcp(ifp, s->mac, dst_ip, TH_PUSH | TH_ACK, c->loc.port,
|
||||
c->rem.port, mg_htonl(s->seq), mg_htonl(s->ack), buf, len);
|
||||
if (sent == 0) {
|
||||
return MG_IO_WAIT;
|
||||
} else if (sent == (size_t) -1) {
|
||||
@ -694,10 +697,10 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
}
|
||||
tx_tcp(c->mgr->ifp, s->mac, rem_ip, flags, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
|
||||
if (pkt->pay.len == 0) return; // if no data, we're done
|
||||
} else if (pkt->pay.len == 0) { // this is an ACK
|
||||
if (pkt->pay.len == 0) return; // if no data, we're done
|
||||
} else if (pkt->pay.len == 0) { // this is an ACK
|
||||
if (s->fin_rcvd && s->ttype == MIP_TTYPE_FIN) s->twclosure = true;
|
||||
return; // no data to process
|
||||
return; // no data to process
|
||||
} else if (seq != s->ack) {
|
||||
uint32_t ack = (uint32_t) (mg_htonl(pkt->tcp->seq) + pkt->pay.len);
|
||||
if (s->ack == ack) {
|
||||
@ -707,11 +710,11 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
tx_tcp(c->mgr->ifp, s->mac, rem_ip, TH_ACK, c->loc.port, c->rem.port,
|
||||
mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
|
||||
}
|
||||
return; // drop it
|
||||
return; // drop it
|
||||
} else if (io->size - io->len < pkt->pay.len &&
|
||||
!mg_iobuf_resize(io, io->len + pkt->pay.len)) {
|
||||
mg_error(c, "oom");
|
||||
return; // drop it
|
||||
return; // drop it
|
||||
}
|
||||
// Copy TCP payload into the IO buffer. If the connection is plain text,
|
||||
// we copy to c->recv. If the connection is TLS, this data is encrypted,
|
||||
@ -747,6 +750,25 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
|
||||
}
|
||||
}
|
||||
|
||||
// process options (MSS)
|
||||
static void handle_opt(struct connstate *s, struct tcp *tcp) {
|
||||
uint8_t *opts = (uint8_t *) (tcp + 1);
|
||||
int len = 4 * ((int) (tcp->off >> 4) - (sizeof(*tcp) / 4));
|
||||
s->dmss = 536; // assume default, RFC-9293 3.7.1
|
||||
while (len > 0) { // RFC-9293 3.1 3.2
|
||||
uint8_t kind = opts[0], optlen = 1;
|
||||
if (kind != 1) { // No-Operation
|
||||
if (kind == 0) break; // End of Option List
|
||||
optlen = opts[1];
|
||||
if (kind == 2 && optlen == 4) // set received MSS
|
||||
s->dmss = (uint16_t) (((uint16_t) opts[2] << 8) + opts[3]);
|
||||
}
|
||||
MG_INFO(("kind: %u, optlen: %u, len: %d\n", kind, optlen, len));
|
||||
opts += optlen;
|
||||
len -= optlen;
|
||||
}
|
||||
}
|
||||
|
||||
static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
struct mg_connection *c = getpeer(ifp->mgr, pkt, false);
|
||||
struct connstate *s = c == NULL ? NULL : (struct connstate *) (c + 1);
|
||||
@ -754,6 +776,7 @@ static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
MG_INFO(("%lu %hhu %d", c ? c->id : 0, pkt->tcp->flags, (int) pkt->pay.len));
|
||||
#endif
|
||||
if (c != NULL && c->is_connecting && pkt->tcp->flags == (TH_SYN | TH_ACK)) {
|
||||
handle_opt(s, pkt->tcp); // process options (MSS)
|
||||
s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq) + 1;
|
||||
tx_tcp_pkt(ifp, pkt, TH_ACK, pkt->tcp->ack, NULL, 0);
|
||||
c->is_connecting = 0; // Client connected
|
||||
@ -783,6 +806,8 @@ static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
|
||||
if (c->is_accepted) mg_error(c, "peer RST"); // RFC-1122 4.2.2.13
|
||||
// ignore RST if not connected
|
||||
} else if (pkt->tcp->flags & TH_SYN) {
|
||||
// TODO(): handle_opt(s, pkt->tcp); // process options (MSS)
|
||||
// At this point, s = NULL, there is no connection.
|
||||
// Use peer's source port as ISN, in order to recognise the handshake
|
||||
uint32_t isn = mg_htonl((uint32_t) mg_ntohs(pkt->tcp->sport));
|
||||
tx_tcp_pkt(ifp, pkt, TH_SYN | TH_ACK, isn, NULL, 0);
|
||||
@ -1038,7 +1063,7 @@ void mg_tcpip_init(struct mg_mgr *mgr, struct mg_tcpip_if *ifp) {
|
||||
MG_INFO(("MAC not set. Generated random: %M", mg_print_mac, ifp->mac));
|
||||
}
|
||||
|
||||
// Uf DHCP name is not set, use "mip"
|
||||
// If DHCP name is not set, use "mip"
|
||||
if (ifp->dhcp_name[0] == '\0') {
|
||||
memcpy(ifp->dhcp_name, "mip", 4);
|
||||
}
|
||||
@ -1228,7 +1253,7 @@ bool mg_send(struct mg_connection *c, const void *buf, size_t len) {
|
||||
|
||||
uint8_t mcast_addr[6] = {0x01, 0x00, 0x5e, 0x00, 0x00, 0xfb};
|
||||
void mg_multicast_add(struct mg_connection *c, char *ip) {
|
||||
(void) ip; // ip4_mcastmac(mcast_mac, &ip);
|
||||
(void) ip; // ip4_mcastmac(mcast_mac, &ip);
|
||||
// TODO(): actual IP -> MAC; check database, update
|
||||
c->mgr->ifp->update_mac_hash_table = true; // mark dirty
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user