#define SETUP_BUFFER_LEN 2048
-#define DEFAULT_KEY_LIFETIME 3600000 /* One hour */
-#define DEFAULT_KEY_RENEGOTIATE_GAP 300000 /* Five minutes */
+#define DEFAULT_KEY_LIFETIME (3600*1000) /* [ms] */
+#define DEFAULT_KEY_RENEGOTIATE_GAP (5*60*1000) /* [ms] */
#define DEFAULT_SETUP_RETRIES 5
-#define DEFAULT_SETUP_TIMEOUT 2000
-#define DEFAULT_WAIT_TIME 20000
+#define DEFAULT_SETUP_RETRY_INTERVAL (2*1000) /* [ms] */
+#define DEFAULT_WAIT_TIME (20*1000) /* [ms] */
+
+#define DEFAULT_MOBILE_KEY_LIFETIME (2*24*3600*1000) /* [ms] */
+#define DEFAULT_MOBILE_KEY_RENEGOTIATE_GAP (12*3600*1000) /* [ms] */
+#define DEFAULT_MOBILE_SETUP_RETRIES 30
+#define DEFAULT_MOBILE_SETUP_RETRY_INTERVAL (1*1000) /* [ms] */
+#define DEFAULT_MOBILE_WAIT_TIME (10*1000) /* [ms] */
+
+#define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */
+#define DEFAULT_MOBILE_PEERS_MAX 3 /* send at most this many copies (default) */
/* Each site can be in one of several possible states. */
#define LOG_DROP 0x00000080
#define LOG_DUMP 0x00000100
#define LOG_ERROR 0x00000400
+#define LOG_PEER_ADDRS 0x00000800
static struct flagstr log_event_table[]={
{ "unexpected", LOG_UNEXPECTED },
{ "packet-drop", LOG_DROP },
{ "dump-packets", LOG_DUMP },
{ "errors", LOG_ERROR },
+ { "peer-addrs", LOG_PEER_ADDRS },
{ "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT|
LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR },
{ "all", 0xffffffff },
{ NULL, 0 }
};
+
+/***** TRANSPORT PEERS declarations *****/
+
+/* Details of "mobile peer" semantics:
+
+ - We record mobile_peers_max peer address/port numbers ("peers")
+ for key setup, and separately mobile_peers_max for data
+ transfer. If these lists fill up, we retain the newest peers.
+ (For non-mobile peers we only record one of each.)
+
+ - Outgoing packets are sent to every recorded peer in the
+ applicable list.
+
+ - Data transfer peers are straightforward: whenever we successfully
+ process a data packet, we record the peer. Also, whenever we
+ successfully complete a key setup, we merge the key setup
+ peers into the data transfer peers.
+
+ (For "non-mobile" peers we simply copy the peer used for
+ successful key setup, and don't change the peer otherwise.)
+
+ - Key setup peers are slightly more complicated.
+
+ Whenever we receive and successfully process a key exchange
+ packet, we record the peer.
+
+ Whenever we try to initiate a key setup, we copy the list of data
+ transfer peers and use it for key setup. But we also look to see
+ if the config supplies an address and port number and if so we
+ add that as a key setup peer (possibly evicting one of the data
+ transfer peers we just copied).
+
+ (For "non-mobile" peers, if we if we have a configured peer
+ address and port, we always use that; otherwise if we have a
+ current data peer address we use that; otherwise we do not
+ attempt to initiate a key setup for lack of a peer address.)
+
+ "Record the peer" means
+ 1. expire any peers last seen >120s ("mobile-peer-expiry") ago
+ 2. add the peer of the just received packet to the applicable list
+ (possibly evicting older entries)
+ NB that we do not expire peers until an incoming packet arrives.
+
+ */
+
+#define MAX_MOBILE_PEERS_MAX 5 /* send at most this many copies, compiled max */
+
+typedef struct {
+ struct timeval last;
+ struct comm_addr addr;
+} transport_peer;
+
+typedef struct {
+/* configuration information */
+/* runtime information */
+ int npeers;
+ transport_peer peers[MAX_MOBILE_PEERS_MAX];
+} transport_peers;
+
+static void transport_peers_clear(struct site *st, transport_peers *peers);
+static int transport_peers_valid(transport_peers *peers);
+static void transport_peers_copy(struct site *st, transport_peers *dst,
+ const transport_peers *src);
+
+static void transport_setup_msgok(struct site *st, const struct comm_addr *a);
+static void transport_data_msgok(struct site *st, const struct comm_addr *a);
+static bool_t transport_compute_setupinit_peers(struct site *st,
+ const struct comm_addr *configured_addr /* 0 if none or not found */);
+static void transport_record_peer(struct site *st, transport_peers *peers,
+ const struct comm_addr *addr, const char *m);
+
+static void transport_xmit(struct site *st, transport_peers *peers,
+ struct buffer_if *buf, bool_t candebug);
+
+ /***** END of transport peers declarations *****/
+
+
+struct data_key {
+ struct transform_inst_if *transform;
+ uint64_t key_timeout; /* End of life of current key */
+ uint32_t remote_session_id;
+};
+
struct site {
closure_t cl;
struct site_if ops;
/* configuration information */
string_t localname;
string_t remotename;
+ bool_t peer_mobile; /* Mobile client support */
+ int32_t transport_peers_max;
string_t tunname; /* localname<->remotename by default, used in logs */
string_t address; /* DNS name for bootstrapping, optional */
int remoteport; /* Port for bootstrapping, optional */
struct netlink_if *netlink;
- struct comm_if *comm;
+ struct comm_if **comms;
+ int ncomms;
struct resolver_if *resolver;
struct log_if *log;
struct random_if *random;
uint32_t index; /* Index of this site */
int32_t setup_retries; /* How many times to send setup packets */
- int32_t setup_timeout; /* Initial timeout for setup packets */
+ int32_t setup_retry_interval; /* Initial timeout for setup packets */
int32_t wait_timeout; /* How long to wait if setup unsuccessful */
+ int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
int32_t key_lifetime; /* How long a key lasts once set up */
int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
after this time, initiate a new
uint64_t now; /* Most recently seen time */
/* The currently established session */
- uint32_t remote_session_id;
- struct transform_inst_if *current_transform;
- bool_t current_valid;
- uint64_t current_key_timeout; /* End of life of current key */
+ struct data_key current;
+ struct data_key auxiliary_key;
+ bool_t auxiliary_is_new;
uint64_t renegotiate_key_time; /* When we can negotiate a new key */
- struct sockaddr_in peer; /* Current address of peer */
- bool_t peer_valid; /* Peer address becomes invalid when key times out,
- but only if we have a DNS name for our peer */
+ uint64_t auxiliary_renegotiate_key_time;
+ transport_peers peers; /* Current address(es) of peer for data traffic */
/* The current key setup protocol exchange. We can only be
involved in one of these at a time. There's a potential for
timeout before we can listen for another setup packet); perhaps
we should keep a list of 'bad' sources for setup packets. */
uint32_t setup_session_id;
- struct sockaddr_in setup_peer;
+ transport_peers setup_peers;
uint8_t localN[NONCELEN]; /* Nonces for key exchange */
uint8_t remoteN[NONCELEN];
struct buffer_if buffer; /* Current outgoing key exchange packet */
+ struct buffer_if scratch;
int32_t retries; /* Number of retries remaining */
uint64_t timeout; /* Timeout for current state */
uint8_t *dhsecret;
case LOG_DROP: class=M_DEBUG; break;
case LOG_DUMP: class=M_DEBUG; break;
case LOG_ERROR: class=M_ERR; break;
+ case LOG_PEER_ADDRS: class=M_DEBUG; break;
default: class=M_ERR; break;
}
}
static void set_link_quality(struct site *st);
-static void delete_key(struct site *st, cstring_t reason, uint32_t loglevel);
+static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
+static void delete_one_key(struct site *st, struct data_key *key,
+ const char *reason /* may be 0 meaning don't log*/,
+ const char *which /* ignored if !reasonn */,
+ uint32_t loglevel /* ignored if !reasonn */);
static bool_t initiate_key_setup(struct site *st, cstring_t reason);
static void enter_state_run(struct site *st);
static bool_t enter_state_resolve(struct site *st);
static bool_t enter_new_state(struct site *st,uint32_t next);
static void enter_state_wait(struct site *st);
+static void activate_new_key(struct site *st);
+
+static bool_t current_valid(struct site *st)
+{
+ return st->current.transform->valid(st->current.transform->st);
+}
#define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
#define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
return False;
}
if (type==LABEL_MSG2) return True;
- if (memcmp(m->nR,st->remoteN,NONCELEN)!=0) {
+ if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
*error="wrong remotely-generated nonce";
return False;
}
}
static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
- struct sockaddr_in *src)
+ const struct comm_addr *src)
{
struct msg m;
if (!unpick_msg(st,LABEL_MSG1,msg1,&m)) return False;
- st->setup_peer=*src;
+ transport_record_peer(st,&st->setup_peers,src,"msg1");
st->setup_session_id=m.source;
memcpy(st->remoteN,m.nR,NONCELEN);
return True;
}
static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
- struct sockaddr_in *src)
+ const struct comm_addr *src)
{
struct msg m;
cstring_t err;
}
static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
- struct sockaddr_in *src)
+ const struct comm_addr *src)
{
struct msg m;
uint8_t *hash;
}
static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
- struct sockaddr_in *src)
+ const struct comm_addr *src)
{
struct msg m;
uint8_t *hash;
buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
- st->netlink->output_config(st->netlink->st,&st->buffer);
buf_prepend_uint32(&st->buffer,LABEL_MSG5);
st->new_transform->forwards(st->new_transform->st,&st->buffer,
&transform_err);
}
static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
- struct sockaddr_in *src)
+ const struct comm_addr *src,
+ struct transform_inst_if *transform)
{
struct msg0 m;
cstring_t transform_err;
if (!unpick_msg0(st,msg5,&m)) return False;
- if (st->new_transform->reverse(st->new_transform->st,
- msg5,&transform_err)) {
+ if (transform->reverse(transform->st,msg5,&transform_err)) {
/* There's a problem */
slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
return False;
slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
return False;
}
- if (!st->netlink->check_config(st->netlink->st,msg5)) {
- slog(st,LOG_SEC,"MSG5/PING packet contained bad netlink config");
- return False;
- }
- CHECK_EMPTY(msg5);
+ /* Older versions of secnet used to write some config data here
+ * which we ignore. So we don't CHECK_EMPTY */
return True;
}
-static bool_t generate_msg6(struct site *st)
+static void create_msg6(struct site *st, struct transform_inst_if *transform,
+ uint32_t session_id)
{
cstring_t transform_err;
buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
- st->netlink->output_config(st->netlink->st,&st->buffer);
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
- st->new_transform->forwards(st->new_transform->st,&st->buffer,
- &transform_err);
+ transform->forwards(transform->st,&st->buffer,&transform_err);
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
buf_prepend_uint32(&st->buffer,st->index);
- buf_prepend_uint32(&st->buffer,st->setup_session_id);
+ buf_prepend_uint32(&st->buffer,session_id);
+}
+static bool_t generate_msg6(struct site *st)
+{
+ create_msg6(st,st->new_transform,st->setup_session_id);
st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
return True;
}
static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
- struct sockaddr_in *src)
+ const struct comm_addr *src)
{
struct msg0 m;
cstring_t transform_err;
slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
return False;
}
- if (!st->netlink->check_config(st->netlink->st,msg6)) {
- slog(st,LOG_SEC,"MSG6/PONG packet contained bad netlink config");
- return False;
- }
- CHECK_EMPTY(msg6);
+ /* Older versions of secnet used to write some config data here
+ * which we ignore. So we don't CHECK_EMPTY */
return True;
}
-static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
- struct sockaddr_in *src)
+static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0)
{
+ cstring_t transform_err, auxkey_err, newkey_err="n/a";
struct msg0 m;
- cstring_t transform_err;
- uint32_t type;
+ uint32_t problem;
+
+ if (!unpick_msg0(st,msg0,&m)) return False;
+
+ /* Keep a copy so we can try decrypting it with multiple keys */
+ buffer_copy(&st->scratch, msg0);
+
+ problem = st->current.transform->reverse(st->current.transform->st,
+ msg0,&transform_err);
+ if (!problem) {
+ if (!st->auxiliary_is_new)
+ delete_one_key(st,&st->auxiliary_key,
+ "peer has used new key","auxiliary key",LOG_SEC);
+ return True;
+ }
- if (!st->current_valid) {
- slog(st,LOG_DROP,"incoming message but no current key -> dropping");
- return initiate_key_setup(st,"incoming message but no current key");
+ if (problem==2) {
+ slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
+ return False;
}
- if (!unpick_msg0(st,msg0,&m)) return False;
+ buffer_copy(msg0, &st->scratch);
+ problem = st->auxiliary_key.transform->reverse
+ (st->auxiliary_key.transform->st,msg0,&auxkey_err);
+ if (problem==0) {
+ slog(st,LOG_DROP,"processing packet which uses auxiliary key");
+ if (st->auxiliary_is_new) {
+ /* We previously timed out in state SENTMSG5 but it turns
+ * out that our peer did in fact get our MSG5 and is
+ * using the new key. So we should switch to it too. */
+ /* This is a bit like activate_new_key. */
+ struct data_key t;
+ t=st->current;
+ st->current=st->auxiliary_key;
+ st->auxiliary_key=t;
+
+ delete_one_key(st,&st->auxiliary_key,"peer has used new key",
+ "previous key",LOG_SEC);
+ st->auxiliary_is_new=0;
+ st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
+ }
+ return True;
+ }
- if (st->current_transform->reverse(st->current_transform->st,
- msg0,&transform_err)) {
- /* There's a problem */
- slog(st,LOG_SEC,"transform: %s",transform_err);
- return initiate_key_setup(st,"incoming message would not decrypt");
+ if (st->state==SITE_SENTMSG5) {
+ buffer_copy(msg0, &st->scratch);
+ if (!st->new_transform->reverse(st->new_transform->st,
+ msg0,&newkey_err)) {
+ /* It looks like we didn't get the peer's MSG6 */
+ /* This is like a cut-down enter_new_state(SITE_RUN) */
+ slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
+ BUF_FREE(&st->buffer);
+ st->timeout=0;
+ activate_new_key(st);
+ return True; /* do process the data in this packet */
+ }
}
+
+ slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
+ transform_err,auxkey_err,newkey_err);
+ initiate_key_setup(st,"incoming message would not decrypt");
+ return False;
+}
+
+static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
+ const struct comm_addr *src)
+{
+ uint32_t type;
+
+ if (!decrypt_msg0(st,msg0))
+ return False;
+
CHECK_AVAIL(msg0,4);
type=buf_unprepend_uint32(msg0);
switch(type) {
case LABEL_MSG7:
/* We must forget about the current session. */
- delete_key(st,"request from peer",LOG_SEC);
+ delete_keys(st,"request from peer",LOG_SEC);
return True;
- break;
case LABEL_MSG9:
/* Deliver to netlink layer */
st->netlink->deliver(st->netlink->st,msg0);
+ transport_data_msgok(st,src);
+ /* See whether we should start negotiating a new key */
+ if (st->now > st->renegotiate_key_time)
+ initiate_key_setup(st,"incoming packet in renegotiation window");
return True;
- break;
default:
slog(st,LOG_SEC,"incoming encrypted message of type %08x "
"(unknown)",type);
}
static void dump_packet(struct site *st, struct buffer_if *buf,
- struct sockaddr_in *addr, bool_t incoming)
+ const struct comm_addr *addr, bool_t incoming)
{
uint32_t dest=ntohl(*(uint32_t *)buf->start);
uint32_t source=ntohl(*(uint32_t *)(buf->start+4));
static bool_t send_msg(struct site *st)
{
if (st->retries>0) {
- dump_packet(st,&st->buffer,&st->setup_peer,False);
- st->comm->sendmsg(st->comm->st,&st->buffer,&st->setup_peer);
- st->timeout=st->now+st->setup_timeout;
+ transport_xmit(st, &st->setup_peers, &st->buffer, True);
+ st->timeout=st->now+st->setup_retry_interval;
st->retries--;
return True;
+ } else if (st->state==SITE_SENTMSG5) {
+ slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key");
+ /* We stash the key we have produced, in case it turns out that
+ * our peer did see our MSG5 after all and starts using it. */
+ /* This is a bit like some of activate_new_key */
+ struct transform_inst_if *t;
+ t=st->auxiliary_key.transform;
+ st->auxiliary_key.transform=st->new_transform;
+ st->new_transform=t;
+
+ t->delkey(t->st);
+ st->auxiliary_is_new=1;
+ st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
+ st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
+ st->auxiliary_key.remote_session_id=st->setup_session_id;
+
+ enter_state_wait(st);
+ return False;
} else {
slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet "
"(in state %s)",state_name(st->state));
static void site_resolve_callback(void *sst, struct in_addr *address)
{
struct site *st=sst;
+ struct comm_addr ca_buf, *ca_use;
if (st->state!=SITE_RESOLVE) {
slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly");
return;
}
if (address) {
- memset(&st->setup_peer,0,sizeof(st->setup_peer));
- st->setup_peer.sin_family=AF_INET;
- st->setup_peer.sin_port=htons(st->remoteport);
- st->setup_peer.sin_addr=*address;
- enter_new_state(st,SITE_SENTMSG1);
+ FILLZERO(ca_buf);
+ ca_buf.comm=st->comms[0];
+ ca_buf.sin.sin_family=AF_INET;
+ ca_buf.sin.sin_port=htons(st->remoteport);
+ ca_buf.sin.sin_addr=*address;
+ ca_use=&ca_buf;
} else {
- /* Resolution failed */
slog(st,LOG_ERROR,"resolution of %s failed",st->address);
+ ca_use=0;
+ }
+ if (transport_compute_setupinit_peers(st,ca_use)) {
+ enter_new_state(st,SITE_SENTMSG1);
+ } else {
+ /* Can't figure out who to try to to talk to */
+ slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address");
enter_state_run(st);
}
}
if (st->address) {
slog(st,LOG_SETUP_INIT,"resolving peer address");
return enter_state_resolve(st);
- } else if (st->peer_valid) {
- slog(st,LOG_SETUP_INIT,"using old peer address");
- st->setup_peer=st->peer;
+ } else if (transport_compute_setupinit_peers(st,0)) {
return enter_new_state(st,SITE_SENTMSG1);
}
slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
{
struct transform_inst_if *t;
- /* We have two transform instances, which we swap between active
- and setup */
- t=st->current_transform;
- st->current_transform=st->new_transform;
+ /* We have three transform instances, which we swap between old,
+ active and setup */
+ t=st->auxiliary_key.transform;
+ st->auxiliary_key.transform=st->current.transform;
+ st->current.transform=st->new_transform;
st->new_transform=t;
t->delkey(t->st);
st->timeout=0;
- st->current_valid=True;
- st->current_key_timeout=st->now+st->key_lifetime;
+ st->auxiliary_is_new=0;
+ st->auxiliary_key.key_timeout=st->current.key_timeout;
+ st->current.key_timeout=st->now+st->key_lifetime;
st->renegotiate_key_time=st->now+st->key_renegotiate_time;
- st->peer=st->setup_peer;
- st->peer_valid=True;
- st->remote_session_id=st->setup_session_id;
+ transport_peers_copy(st,&st->peers,&st->setup_peers);
+ st->current.remote_session_id=st->setup_session_id;
slog(st,LOG_ACTIVATE_KEY,"new key activated");
enter_state_run(st);
}
-static void delete_key(struct site *st, cstring_t reason, uint32_t loglevel)
+static void delete_one_key(struct site *st, struct data_key *key,
+ cstring_t reason, cstring_t which, uint32_t loglevel)
+{
+ if (!key->transform->valid(key->transform->st)) return;
+ if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
+ key->transform->delkey(key->transform->st);
+ key->key_timeout=0;
+}
+
+static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
{
- if (st->current_valid) {
+ if (current_valid(st)) {
slog(st,loglevel,"session closed (%s)",reason);
- st->current_valid=False;
- st->current_transform->delkey(st->current_transform->st);
- st->current_key_timeout=0;
+ delete_one_key(st,&st->current,0,0,0);
set_link_quality(st);
}
+ delete_one_key(st,&st->auxiliary_key,0,0,0);
}
static void state_assert(struct site *st, bool_t ok)
{
st->state=SITE_STOP;
st->timeout=0;
- delete_key(st,"entering state STOP",LOG_TIMEOUT_KEY);
+ delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
st->new_transform->delkey(st->new_transform->st);
}
static void set_link_quality(struct site *st)
{
uint32_t quality;
- if (st->current_valid)
+ if (current_valid(st))
quality=LINK_QUALITY_UP;
else if (st->state==SITE_WAIT || st->state==SITE_STOP)
quality=LINK_QUALITY_DOWN;
else if (st->address)
quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
- else if (st->peer_valid)
+ else if (transport_peers_valid(&st->peers))
quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
else
quality=LINK_QUALITY_DOWN;
st->timeout=0;
st->setup_session_id=0;
- memset(&st->setup_peer,0,sizeof(st->setup_peer));
+ transport_peers_clear(st,&st->setup_peers);
memset(st->localN,0,NONCELEN);
memset(st->remoteN,0,NONCELEN);
st->new_transform->delkey(st->new_transform->st);
r= gen(st) && send_msg(st);
hacky_par_end(&r,
- st->setup_retries, st->setup_timeout,
+ st->setup_retries, st->setup_retry_interval,
send_msg, st);
if (r) {
{
cstring_t transform_err;
- if (st->current_valid && st->peer_valid && st->buffer.free) {
+ if (current_valid(st) && st->buffer.free
+ && transport_peers_valid(&st->peers)) {
BUF_ALLOC(&st->buffer,"site:MSG7");
buffer_init(&st->buffer,st->transform->max_start_pad+(4*3));
buf_append_uint32(&st->buffer,LABEL_MSG7);
buf_append_string(&st->buffer,reason);
- st->current_transform->forwards(st->current_transform->st,
+ st->current.transform->forwards(st->current.transform->st,
&st->buffer, &transform_err);
buf_prepend_uint32(&st->buffer,LABEL_MSG0);
buf_prepend_uint32(&st->buffer,st->index);
- buf_prepend_uint32(&st->buffer,st->remote_session_id);
- st->comm->sendmsg(st->comm->st,&st->buffer,&st->peer);
+ buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
+ transport_xmit(st,&st->peers,&st->buffer,True);
BUF_FREE(&st->buffer);
return True;
}
st->now=*now;
/* Work out when our next timeout is. The earlier of 'timeout' or
- 'current_key_timeout'. A stored value of '0' indicates no timeout
+ 'current.key_timeout'. A stored value of '0' indicates no timeout
active. */
site_settimeout(st->timeout, timeout_io);
- site_settimeout(st->current_key_timeout, timeout_io);
+ site_settimeout(st->current.key_timeout, timeout_io);
+ site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
return 0; /* success */
}
+static void check_expiry(struct site *st, struct data_key *key,
+ const char *which)
+{
+ if (key->key_timeout && *now>key->key_timeout) {
+ delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
+ }
+}
+
/* NB site_afterpoll will be called before site_beforepoll is ever called */
static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
{
st->state);
}
}
- if (st->current_key_timeout && *now>st->current_key_timeout) {
- delete_key(st,"maximum key life exceeded",LOG_TIMEOUT_KEY);
- }
+ check_expiry(st,&st->current,"current key");
+ check_expiry(st,&st->auxiliary_key,"auxiliary key");
}
/* This function is called by the netlink device to deliver packets
/* In all other states we consider delivering the packet if we have
a valid key and a valid address to send it to. */
- if (st->current_valid && st->peer_valid) {
+ if (current_valid(st) && transport_peers_valid(&st->peers)) {
/* Transform it and send it */
if (buf->size>0) {
buf_prepend_uint32(buf,LABEL_MSG9);
- st->current_transform->forwards(st->current_transform->st,
+ st->current.transform->forwards(st->current.transform->st,
buf, &transform_err);
buf_prepend_uint32(buf,LABEL_MSG0);
buf_prepend_uint32(buf,st->index);
- buf_prepend_uint32(buf,st->remote_session_id);
- st->comm->sendmsg(st->comm->st,buf,&st->peer);
+ buf_prepend_uint32(buf,st->current.remote_session_id);
+ transport_xmit(st,&st->peers,buf,False);
}
BUF_FREE(buf);
- /* See whether we should start negotiating a new key */
- if (st->now > st->renegotiate_key_time)
- initiate_key_setup(st,"outgoing packet in renegotiation window");
return;
}
/* This function is called by the communication device to deliver
packets from our peers. */
static bool_t site_incoming(void *sst, struct buffer_if *buf,
- struct sockaddr_in *source)
+ const struct comm_addr *source)
{
struct site *st=sst;
+
+ if (buf->size < 12) return False;
+
uint32_t dest=ntohl(*(uint32_t *)buf->start);
if (dest==0) {
case 0: /* NAK */
/* If the source is our current peer then initiate a key setup,
because our peer's forgotten the key */
- if (get_uint32(buf->start+4)==st->remote_session_id) {
+ if (get_uint32(buf->start+4)==st->current.remote_session_id) {
initiate_key_setup(st,"received a NAK");
} else {
slog(st,LOG_SEC,"bad incoming NAK");
/* Setup packet: expected only in state SENTMSG1 */
if (st->state!=SITE_SENTMSG1) {
slog(st,LOG_UNEXPECTED,"unexpected MSG2");
- } else if (process_msg2(st,buf,source))
+ } else if (process_msg2(st,buf,source)) {
+ transport_setup_msgok(st,source);
enter_new_state(st,SITE_SENTMSG3);
- else {
+ } else {
slog(st,LOG_SEC,"invalid MSG2");
}
break;
/* Setup packet: expected only in state SENTMSG2 */
if (st->state!=SITE_SENTMSG2) {
slog(st,LOG_UNEXPECTED,"unexpected MSG3");
- } else if (process_msg3(st,buf,source))
+ } else if (process_msg3(st,buf,source)) {
+ transport_setup_msgok(st,source);
enter_new_state(st,SITE_SENTMSG4);
- else {
+ } else {
slog(st,LOG_SEC,"invalid MSG3");
}
break;
/* Setup packet: expected only in state SENTMSG3 */
if (st->state!=SITE_SENTMSG3) {
slog(st,LOG_UNEXPECTED,"unexpected MSG4");
- } else if (process_msg4(st,buf,source))
+ } else if (process_msg4(st,buf,source)) {
+ transport_setup_msgok(st,source);
enter_new_state(st,SITE_SENTMSG5);
- else {
+ } else {
slog(st,LOG_SEC,"invalid MSG4");
}
break;
/* Setup packet: expected only in state SENTMSG4 */
/* (may turn up in state RUN if our return MSG6 was lost
and the new key has already been activated. In that
- case we should treat it as an ordinary PING packet. We
- can't pass it to process_msg5() because the
- new_transform will now be unkeyed. XXX) */
- if (st->state!=SITE_SENTMSG4) {
- slog(st,LOG_UNEXPECTED,"unexpected MSG5");
- } else if (process_msg5(st,buf,source)) {
- enter_new_state(st,SITE_RUN);
+ case we discard it. The peer will realise that we
+ are using the new key when they see our data packets.
+ Until then the peer's data packets to us get discarded. */
+ if (st->state==SITE_SENTMSG4) {
+ if (process_msg5(st,buf,source,st->new_transform)) {
+ transport_setup_msgok(st,source);
+ enter_new_state(st,SITE_RUN);
+ } else {
+ slog(st,LOG_SEC,"invalid MSG5");
+ }
+ } else if (st->state==SITE_RUN) {
+ if (process_msg5(st,buf,source,st->current.transform)) {
+ slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
+ transport_setup_msgok(st,source);
+ create_msg6(st,st->current.transform,
+ st->current.remote_session_id);
+ transport_xmit(st,&st->peers,&st->buffer,True);
+ BUF_FREE(&st->buffer);
+ } else {
+ slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
+ }
} else {
- slog(st,LOG_SEC,"invalid MSG5");
+ slog(st,LOG_UNEXPECTED,"unexpected MSG5");
}
break;
case LABEL_MSG6:
slog(st,LOG_UNEXPECTED,"unexpected MSG6");
} else if (process_msg6(st,buf,source)) {
BUF_FREE(&st->buffer); /* Free message 5 */
+ transport_setup_msgok(st,source);
activate_new_key(st);
} else {
slog(st,LOG_SEC,"invalid MSG6");
struct site *st;
item_t *item;
dict_t *dict;
+ int i;
st=safe_malloc(sizeof(*st),"site_apply");
dict=item->data.dict;
st->localname=dict_read_string(dict, "local-name", True, "site", loc);
st->remotename=dict_read_string(dict, "name", True, "site", loc);
+
+ st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
+ bool_t local_mobile=
+ dict_read_bool(dict,"local-mobile",False,"site",loc,False);
+
/* Sanity check (which also allows the 'sites' file to include
site() closures for all sites including our own): refuse to
talk to ourselves */
if (strcmp(st->localname,st->remotename)==0) {
Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
st->localname);
+ if (st->peer_mobile != local_mobile)
+ cfgfatal(loc,"site","site %s's peer-mobile=%d"
+ " but our local-mobile=%d\n",
+ st->localname, st->peer_mobile, local_mobile);
+ free(st);
+ return NULL;
+ }
+ if (st->peer_mobile && local_mobile) {
+ Message(M_WARNING,"site %s: site is mobile but so are we"
+ " -> ignoring this site\n", st->remotename);
free(st);
return NULL;
}
+
assert(index_sequence < 0xffffffffUL);
st->index = ++index_sequence;
st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
- st->comm=find_cl_if(dict,"comm",CL_COMM,True,"site",loc);
+
+ list_t *comms_cfg=dict_lookup(dict,"comm");
+ if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n");
+ st->ncomms=list_length(comms_cfg);
+ st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms");
+ assert(st->ncomms);
+ for (i=0; i<st->ncomms; i++) {
+ item_t *item=list_elem(comms_cfg,i);
+ if (item->type!=t_closure)
+ cfgfatal(loc,"site","comm is not a closure\n");
+ closure_t *cl=item->data.closure;
+ if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n");
+ st->comms[i]=cl->interface;
+ }
+
st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
- st->key_lifetime=dict_read_number(
- dict,"key-lifetime",False,"site",loc,DEFAULT_KEY_LIFETIME);
- st->setup_retries=dict_read_number(
- dict,"setup-retries",False,"site",loc,DEFAULT_SETUP_RETRIES);
- st->setup_timeout=dict_read_number(
- dict,"setup-timeout",False,"site",loc,DEFAULT_SETUP_TIMEOUT);
- st->wait_timeout=dict_read_number(
- dict,"wait-time",False,"site",loc,DEFAULT_WAIT_TIME);
+#define DEFAULT(D) (st->peer_mobile || local_mobile \
+ ? DEFAULT_MOBILE_##D : DEFAULT_##D)
+#define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
- if (st->key_lifetime < DEFAULT_KEY_RENEGOTIATE_GAP*2)
+ st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
+ st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
+ st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
+ st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
+
+ st->mobile_peer_expiry= dict_read_number(
+ dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
+
+ st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number(
+ dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX);
+ if (st->transport_peers_max<1 ||
+ st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) {
+ cfgfatal(loc,"site","mobile-peers-max must be in range 1.."
+ STRING(MAX_MOBILE_PEERS_MAX) "\n");
+ }
+
+ if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
st->key_renegotiate_time=st->key_lifetime/2;
else
- st->key_renegotiate_time=st->key_lifetime-DEFAULT_KEY_RENEGOTIATE_GAP;
+ st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
st->key_renegotiate_time=dict_read_number(
dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
if (st->key_renegotiate_time > st->key_lifetime) {
buffer_new(&st->buffer,SETUP_BUFFER_LEN);
+ buffer_new(&st->scratch,0);
+ BUF_ALLOC(&st->scratch,"site:scratch");
+
/* We are interested in poll(), but only for timeouts. We don't have
any fds of our own. */
register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site");
st->timeout=0;
- st->current_valid=False;
- st->current_key_timeout=0;
- st->peer_valid=False;
+ st->current.key_timeout=0;
+ st->auxiliary_key.key_timeout=0;
+ transport_peers_clear(st,&st->peers);
+ transport_peers_clear(st,&st->setup_peers);
/* XXX mlock these */
st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
st->sharedsecret=safe_malloc(st->transform->keylen,"site:sharedsecret");
+ /* We need to compute some properties of our comms */
+#define COMPUTE_WORST(pad) \
+ int worst_##pad=0; \
+ for (i=0; i<st->ncomms; i++) { \
+ int thispad=st->comms[i]->pad; \
+ if (thispad > worst_##pad) \
+ worst_##pad=thispad; \
+ }
+ COMPUTE_WORST(min_start_pad)
+ COMPUTE_WORST(min_end_pad)
+
/* We need to register the remote networks with the netlink device */
st->netlink->reg(st->netlink->st, site_outgoing, st,
st->transform->max_start_pad+(4*4)+
- st->comm->min_start_pad,
- st->transform->max_end_pad+st->comm->min_end_pad);
+ worst_min_start_pad,
+ st->transform->max_end_pad+worst_min_end_pad);
- st->comm->request_notify(st->comm->st, st, site_incoming);
+ for (i=0; i<st->ncomms; i++)
+ st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
- st->current_transform=st->transform->create(st->transform->st);
+ st->current.transform=st->transform->create(st->transform->st);
+ st->auxiliary_key.transform=st->transform->create(st->transform->st);
st->new_transform=st->transform->create(st->transform->st);
+ st->auxiliary_is_new=0;
enter_state_stop(st);
{
add_closure(dict,"site",site_apply);
}
+
+
+/***** TRANSPORT PEERS definitions *****/
+
+static void transport_peers_debug(struct site *st, transport_peers *dst,
+ const char *didwhat,
+ int nargs, const struct comm_addr *args,
+ size_t stride) {
+ int i;
+ char *argp;
+
+ if (!(st->log_events & LOG_PEER_ADDRS))
+ return; /* an optimisation */
+
+ slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
+ (dst==&st->peers ? "data" :
+ dst==&st->setup_peers ? "setup" : "UNKNOWN"),
+ didwhat, nargs, dst->npeers);
+
+ for (i=0, argp=(void*)args;
+ i<nargs;
+ i++, (argp+=stride?stride:sizeof(*args))) {
+ const struct comm_addr *ca=(void*)argp;
+ slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
+ i, ca->comm->addr_to_string(ca->comm->st,ca));
+ }
+ for (i=0; i<dst->npeers; i++) {
+ struct timeval diff;
+ timersub(tv_now,&dst->peers[i].last,&diff);
+ const struct comm_addr *ca=&dst->peers[i].addr;
+ slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
+ i, ca->comm->addr_to_string(ca->comm->st,ca),
+ (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
+ }
+}
+
+static int transport_peer_compar(const void *av, const void *bv) {
+ const transport_peer *a=av;
+ const transport_peer *b=bv;
+ /* put most recent first in the array */
+ if (timercmp(&a->last, &b->last, <)) return +1;
+ if (timercmp(&a->last, &b->last, >)) return -11;
+ return 0;
+}
+
+static void transport_peers_expire(struct site *st, transport_peers *peers) {
+ /* peers must be sorted first */
+ int previous_peers=peers->npeers;
+ struct timeval oldest;
+ oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
+ oldest.tv_usec = tv_now->tv_usec;
+ while (peers->npeers>1 &&
+ timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
+ peers->npeers--;
+ if (peers->npeers != previous_peers)
+ transport_peers_debug(st,peers,"expire", 0,0,0);
+}
+
+static void transport_record_peer(struct site *st, transport_peers *peers,
+ const struct comm_addr *addr, const char *m) {
+ int slot, changed=0;
+
+ for (slot=0; slot<peers->npeers; slot++)
+ if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr)))
+ goto found;
+
+ changed=1;
+ if (peers->npeers==st->transport_peers_max)
+ slot=st->transport_peers_max;
+ else
+ slot=peers->npeers++;
+
+ found:
+ peers->peers[slot].addr=*addr;
+ peers->peers[slot].last=*tv_now;
+
+ if (peers->npeers>1)
+ qsort(peers->peers, peers->npeers,
+ sizeof(*peers->peers), transport_peer_compar);
+
+ if (changed || peers->npeers!=1)
+ transport_peers_debug(st,peers,m, 1,addr,0);
+ transport_peers_expire(st, peers);
+}
+
+static bool_t transport_compute_setupinit_peers(struct site *st,
+ const struct comm_addr *configured_addr /* 0 if none or not found */) {
+
+ if (!configured_addr && !transport_peers_valid(&st->peers))
+ return False;
+
+ slog(st,LOG_SETUP_INIT,
+ (!configured_addr ? "using only %d old peer address(es)"
+ : "using configured address, and/or perhaps %d old peer address(es)"),
+ st->peers);
+
+ /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they
+ * have transport_peers_max==1. The effect is that this code
+ * always uses the configured address if supplied, or otherwise
+ * the existing data peer if one exists; this is as desired. */
+
+ transport_peers_copy(st,&st->setup_peers,&st->peers);
+
+ if (configured_addr)
+ transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit");
+
+ assert(transport_peers_valid(&st->setup_peers));
+ return True;
+}
+
+static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
+ if (st->peer_mobile)
+ transport_record_peer(st,&st->setup_peers,a,"setupmsg");
+}
+static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
+ if (st->peer_mobile)
+ transport_record_peer(st,&st->peers,a,"datamsg");
+}
+
+static int transport_peers_valid(transport_peers *peers) {
+ return peers->npeers;
+}
+static void transport_peers_clear(struct site *st, transport_peers *peers) {
+ peers->npeers= 0;
+ transport_peers_debug(st,peers,"clear",0,0,0);
+}
+static void transport_peers_copy(struct site *st, transport_peers *dst,
+ const transport_peers *src) {
+ dst->npeers=src->npeers;
+ memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers);
+ transport_peers_debug(st,dst,"copy",
+ src->npeers, &src->peers->addr, sizeof(*src->peers));
+}
+
+void transport_xmit(struct site *st, transport_peers *peers,
+ struct buffer_if *buf, bool_t candebug) {
+ int slot;
+ transport_peers_expire(st, peers);
+ for (slot=0; slot<peers->npeers; slot++) {
+ transport_peer *peer=&peers->peers[slot];
+ if (candebug)
+ dump_packet(st, buf, &peer->addr, False);
+ peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
+ }
+}
+
+/***** END of transport peers declarations *****/