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Native packet processing order

This commit is contained in:
M66B 2016-01-17 14:30:21 +01:00
parent 0c7021e8be
commit 1d874ef4d1
1 changed files with 62 additions and 60 deletions
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122
app/src/main/jni/netguard/netguard.c
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@ -825,64 +825,16 @@ void handle_tcp(JNIEnv *env, jobject instance, const struct arguments *args,
cur->local_seq - cur->local_start,
cur->remote_seq - cur->remote_start);
if (tcphdr->syn)
ng_log(ANDROID_LOG_DEBUG, "Ignoring repeated SYN");
// Do not change order of conditions
else if (tcphdr->ack && !tcphdr->fin) {
if (((uint32_t) ntohl(tcphdr->seq) + 1) == cur->remote_seq) {
// TODO respond to keep alive?
ng_log(ANDROID_LOG_DEBUG, "Keep alive");
cur->time = time(NULL);
} else if (ntohl(tcphdr->ack_seq) == cur->local_seq &&
ntohl(tcphdr->seq) == cur->remote_seq) {
cur->time = time(NULL);
if (cur->state == TCP_SYN_RECV) {
// TODO process data?
cur->state = TCP_ESTABLISHED;
}
else if (cur->state == TCP_ESTABLISHED) {
ng_log(ANDROID_LOG_DEBUG, "New ack data %u", datalen);
if (datalen) {
ng_log(ANDROID_LOG_DEBUG, "send socket data %u",
datalen);
// TODO non blocking
if (send(cur->socket, buffer + dataoff, datalen, 0) < 0) {
ng_log(ANDROID_LOG_ERROR, "send error %d: %s",
errno, strerror(errno));
// Remote will retry
} else {
// TODO can write
if (writeTCP(cur, NULL, 0, datalen, 0, 0, 0, args->tun) < 0) // ACK
ng_log(ANDROID_LOG_ERROR,
"write data error %d: %s",
errno, strerror((errno)));
else
cur->remote_seq += datalen; // received from tun
}
}
}
else if (cur->state == TCP_LAST_ACK) {
// socket has been shutdown already
cur->state = TCP_TIME_WAIT; // Will close socket
}
else if (cur->state == TCP_FIN_WAIT1)
cur->state = TCP_FIN_WAIT2;
else if (cur->state == TCP_CLOSING)
cur->state = TCP_TIME_WAIT;
else
ng_log(ANDROID_LOG_ERROR, "Invalid ACK");
}
else {
// TODO check old seq/ack
ng_log(ANDROID_LOG_WARN, "Invalid ACK seq %u/%u ack %u/%u",
ntohl(tcphdr->seq) - cur->remote_start,
cur->remote_seq - cur->remote_start,
ntohl(tcphdr->ack_seq) - cur->local_start,
cur->local_seq - cur->local_start);
}
if (tcphdr->rst) {
cur->time = time(NULL);
cur->state = TCP_TIME_WAIT; // will close socket
}
else if (tcphdr->syn)
ng_log(ANDROID_LOG_DEBUG, "Ignoring repeated SYN");
else if (tcphdr->fin /* ACK */) {
if (ntohl(tcphdr->ack_seq) == cur->local_seq &&
ntohl(tcphdr->seq) == cur->remote_seq) {
@ -937,13 +889,13 @@ void handle_tcp(JNIEnv *env, jobject instance, const struct arguments *args,
} else if (cur->state == TCP_FIN_WAIT2)
cur->state = TCP_TIME_WAIT;
else
ng_log(ANDROID_LOG_ERROR, "Invalid FIN");
ng_log(ANDROID_LOG_ERROR, "Invalid FIN state %s", strstate(cur->state));
}
}
}
else {
// TODO check old seq/ack
ng_log(ANDROID_LOG_WARN, "Invalid seq %u/%u ack %u/%u",
ng_log(ANDROID_LOG_WARN, "Invalid FIN seq %u/%u ack %u/%u",
ntohl(tcphdr->seq) - cur->remote_start,
cur->remote_seq - cur->remote_start,
ntohl(tcphdr->ack_seq) - cur->local_start,
@ -959,9 +911,59 @@ void handle_tcp(JNIEnv *env, jobject instance, const struct arguments *args,
}
}
else if (tcphdr->rst) {
cur->time = time(NULL);
cur->state = TCP_TIME_WAIT; // will close socket
else if (tcphdr->ack) {
if (((uint32_t) ntohl(tcphdr->seq) + 1) == cur->remote_seq) {
// TODO respond to keep alive?
ng_log(ANDROID_LOG_DEBUG, "Keep alive");
cur->time = time(NULL);
} else if (ntohl(tcphdr->ack_seq) == cur->local_seq &&
ntohl(tcphdr->seq) == cur->remote_seq) {
cur->time = time(NULL);
if (cur->state == TCP_SYN_RECV) {
// TODO process data?
cur->state = TCP_ESTABLISHED;
}
else if (cur->state == TCP_ESTABLISHED) {
ng_log(ANDROID_LOG_DEBUG, "New ack data %u", datalen);
if (datalen) {
ng_log(ANDROID_LOG_DEBUG, "send socket data %u",
datalen);
// TODO non blocking
if (send(cur->socket, buffer + dataoff, datalen, 0) < 0) {
ng_log(ANDROID_LOG_ERROR, "send error %d: %s",
errno, strerror(errno));
// Remote will retry
} else {
// TODO can write
if (writeTCP(cur, NULL, 0, datalen, 0, 0, 0, args->tun) < 0) // ACK
ng_log(ANDROID_LOG_ERROR,
"write data error %d: %s",
errno, strerror((errno)));
else
cur->remote_seq += datalen; // received from tun
}
}
}
else if (cur->state == TCP_LAST_ACK) {
// socket has been shutdown already
cur->state = TCP_TIME_WAIT; // Will close socket
}
else if (cur->state == TCP_FIN_WAIT1)
cur->state = TCP_FIN_WAIT2;
else if (cur->state == TCP_CLOSING)
cur->state = TCP_TIME_WAIT;
else
ng_log(ANDROID_LOG_ERROR, "Invalid ACK state %s", strstate(cur->state));
}
else {
// TODO check old seq/ack
ng_log(ANDROID_LOG_WARN, "Invalid ACK seq %u/%u ack %u/%u",
ntohl(tcphdr->seq) - cur->remote_start,
cur->remote_seq - cur->remote_start,
ntohl(tcphdr->ack_seq) - cur->local_start,
cur->local_seq - cur->local_start);
}
}
else