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Code Issues Releases Wiki Activity

Native log errors, better UDP handling

This commit is contained in:
M66B 2016-01-21 17:24:23 +01:00
parent 70cf8a6077
commit 064f4922fe
1 changed files with 42 additions and 19 deletions
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61
app/src/main/jni/netguard/netguard.c
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@ -453,10 +453,12 @@ int get_selects(const struct arguments *args, fd_set *rfds, fd_set *wfds, fd_set
// Select UDP sockets
struct udp_session *u = udp_session;
while (u != NULL) {
FD_SET(u->socket, efds);
FD_SET(u->socket, rfds);
if (u->socket > max)
max = u->socket;
if (!u->error) {
FD_SET(u->socket, efds);
FD_SET(u->socket, rfds);
if (u->socket > max)
max = u->socket;
}
u = u->next;
}
@ -834,18 +836,22 @@ void handle_ip(const struct arguments *args, const uint8_t *buffer, const uint16
}
// Handle allowed traffic
int log = 0;
if (allowed) {
if (protocol == IPPROTO_UDP)
allowed = handle_udp(args, buffer, length, uid);
else if (protocol == IPPROTO_TCP)
else if (protocol == IPPROTO_TCP) {
allowed = handle_tcp(args, buffer, length, uid);
if (!allowed)
log = 1;
}
else
allowed = 0;
}
// Log traffic
if (args->log) {
if (!args->filter || syn || protocol != IPPROTO_TCP)
if (!args->filter || syn || log || protocol != IPPROTO_TCP)
log_packet(args, time(NULL), version, dest, protocol, dport, flags, uid, allowed);
}
}
@ -875,13 +881,11 @@ jboolean handle_udp(const struct arguments *args, const uint8_t *buffer, uint16_
}
// Create new session if needed
int usock = -1;
if (cur == NULL) {
log_android(ANDROID_LOG_INFO, "UDP new session");
// Register session
struct udp_session *u = malloc(sizeof(struct udp_session));
u->time = time(NULL);
u->uid = uid;
u->version = 4;
u->saddr = iphdr->saddr;
@ -895,6 +899,7 @@ jboolean handle_udp(const struct arguments *args, const uint8_t *buffer, uint16_
u->socket = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (u->socket < 0) {
log_android(ANDROID_LOG_ERROR, "UDP socket error %d: %s", errno, strerror(errno));
u->error = 1;
return 0;
}
else {
@ -905,12 +910,9 @@ jboolean handle_udp(const struct arguments *args, const uint8_t *buffer, uint16_
else
last->next = u;
usock = u->socket;
cur = u;
}
} else {
cur->time = time(NULL);
usock = cur->socket;
}
char source[40];
@ -921,13 +923,16 @@ jboolean handle_udp(const struct arguments *args, const uint8_t *buffer, uint16_
log_android(ANDROID_LOG_INFO, "UDP forward from tun %s/%u to %s/%u data %d",
source, ntohs(udphdr->source), dest, ntohs(udphdr->dest), datalen);
cur->time = time(NULL);
struct sockaddr_in server;
server.sin_family = (version == 4 ? AF_INET : AF_INET6);
server.sin_addr.s_addr = iphdr->daddr;
server.sin_port = udphdr->dest;
if (sendto(usock, buffer + dataoff, datalen, 0, &server, sizeof(server)) != datalen) {
if (sendto(cur->socket, buffer + dataoff, datalen, 0, &server, sizeof(server)) != datalen) {
log_android(ANDROID_LOG_ERROR, "UDP sendto error %s:%s", errno, strerror(errno));
cur->error = 1;
return 0;
}
@ -1014,6 +1019,7 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
syn->state = TCP_TIME_WAIT;
// Remote might retry
free(syn);
return 0;
}
else {
uint16_t lport = get_local_port(syn->socket);
@ -1064,6 +1070,7 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
cur->local_seq - cur->local_start,
cur->remote_seq - cur->remote_start);
write_rst(args, cur, args->tun);
return 0;
}
else {
int oldstate = cur->state;
@ -1090,6 +1097,7 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
log_android(ANDROID_LOG_ERROR, "send error %d: %s", errno, strerror(errno));
ok = 0;
write_rst(args, cur, args->tun);
return 0;
}
else {
if (tcphdr->fin ||
@ -1113,6 +1121,7 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
source, ntohs(tcphdr->source), dest, ntohs(cur->dest),
strstate(cur->state));
cur->state = TCP_TIME_WAIT;
return 0;
}
else {
if (ntohl(tcphdr->ack_seq) == cur->local_seq &&
@ -1131,8 +1140,9 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
if (shutdown(cur->socket, SHUT_WR)) {
log_android(ANDROID_LOG_ERROR, "shutdown WR error %d: %s",
errno, strerror(errno));
write_rst(args, cur, args->tun);
// Data might be lost
write_rst(args, cur, args->tun);
return 0;
}
else {
if (write_ack(args, cur, 1, args->tun) >= 0) {
@ -1145,15 +1155,19 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
cur->state = TCP_CLOSING;
else if (cur->state == TCP_FIN_WAIT2 /* && !tcphdr->ack */)
cur->state = TCP_TIME_WAIT;
else
else {
log_android(ANDROID_LOG_ERROR,
"Invalid FIN from %s/%u to %s/%u state %s ACK %d",
source, ntohs(tcphdr->source),
dest, ntohs(cur->dest),
strstate(cur->state), tcphdr->ack);
return 0;
}
}
else
else {
write_rst(args, cur, args->tun);
return 0;
}
}
}
@ -1174,18 +1188,22 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
cur->state = TCP_FIN_WAIT2;
else if (cur->state == TCP_CLOSING)
cur->state = TCP_TIME_WAIT;
else
else {
log_android(ANDROID_LOG_ERROR,
"Invalid ACK from %s/%u to %s/%u state %s",
source, ntohs(tcphdr->source), dest, ntohs(cur->dest),
strstate(cur->state));
return 0;
}
}
else
else {
log_android(ANDROID_LOG_ERROR,
"Unknown packet from %s/%u to %s/%u state %s",
source, ntohs(tcphdr->source), dest, ntohs(cur->dest),
strstate(cur->state));
return 0;
}
}
else {
char *msg;
@ -1195,6 +1213,7 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
static const char keepalive[] = "Keep alive";
// TODO proper wrap around
int allowed = 1;
if (tcphdr->ack && ((uint32_t) ntohl(tcphdr->seq) + 1) == cur->remote_seq)
msg = keepalive;
else if (ntohl(tcphdr->seq) == cur->remote_seq &&
@ -1203,8 +1222,10 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
else if (ntohl(tcphdr->seq) < cur->remote_seq &&
ntohl(tcphdr->ack_seq) == cur->local_seq)
msg = repeated;
else
else {
msg = invalid;
allowed = 0;
}
char flags[10];
int flen = 0;
@ -1227,6 +1248,8 @@ jboolean handle_tcp(const struct arguments *args, const uint8_t *buffer, uint16_
ntohl(tcphdr->ack_seq) - cur->local_start,
cur->local_seq - cur->local_start,
datalen);
return allowed;
}
}
}