#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. */
/***** TRANSPORT PEERS declarations *****/
/* Details of "mobile peer" semantics:
+
+ - We use the same data structure for the different configurations,
+ but manage it with different algorithms.
- - 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.)
+ - We record up to mobile_peers_max peer address/port numbers
+ ("peers") for key setup, and separately up to mobile_peers_max
+ for data transfer.
+
+ - In general, we make a new set of addrs (see below) when we start
+ a new key exchange; the key setup addrs become the data transport
+ addrs when key setup complets.
+
+ If our peer is mobile:
+
+ - We send to all recent addresses of incoming packets, plus
+ initially all configured addresses (which we also expire).
+
+ - So, we record addrs of good incoming packets, as follows:
+ 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 the oldest entries to make room)
+ NB that we do not expire peers until an incoming packet arrives.
- - Outgoing packets are sent to every recorded peer in the
- applicable list.
+ - If the peer has a configured address or name, we record them the
+ same way, but only as a result of our own initiation of key
+ setup. (We might evict some incoming packet addrs to make room.)
- - 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
+ - The default number of addrs to keep is 3, or 4 if we have a
+ configured name or address. That's space for two configured
+ addresses (one IPv6 and one IPv4), plus two received addresses.
+
+ - Outgoing packets are sent to every recorded address in the
+ applicable list. Any unsupported[1] addresses are deleted from
+ the list right away. (This should only happen to configured
+ addresses, of course, but there is no need to check that.)
+
+ - When 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.)
+ [1] An unsupported address is one for whose AF we don't have a
+ socket (perhaps because we got EAFNOSUPPORT or some such) or for
+ which sendto gives ENETUNREACH.
- - Key setup peers are slightly more complicated.
+ If neither end is mobile:
- Whenever we receive and successfully process a key exchange
- packet, we record the peer.
+ - When peer initiated the key exchange, we use the incoming packet
+ address.
- 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).
+ - When we initiate the key exchange, we try configured addresses
+ until we get one which isn't unsupported then fixate on that.
- (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.)
+ - When we complete a key setup, we replace the data transport peers
+ with those from the key setup.
- "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.
+ If we are mobile:
- */
+ - We can't tell when local network setup changes so we can't cache
+ the unsupported addrs and completely remove the spurious calls to
+ sendto, but we can optimise things a bit by deprioritising addrs
+ which seem to be unsupported.
+
+ - Use only configured addresses. (Except, that if our peer
+ initiated a key exchange we use the incoming packet address until
+ our name resolution completes.)
+
+ - When we send a packet, try each address in turn; if addr
+ supported, put that address to the end of the list for future
+ packets, and go onto the next address.
-#define MAX_MOBILE_PEERS_MAX 5 /* send at most this many copies, compiled max */
+ - When we complete a key setup, we replace the data transport peers
+ with those from the key setup.
+
+ */
typedef struct {
struct timeval last;
/* configuration information */
/* runtime information */
int npeers;
- transport_peer peers[MAX_MOBILE_PEERS_MAX];
+ transport_peer peers[MAX_PEER_ADDRS];
} transport_peers;
+/* Basic operations on transport peer address sets */
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);
+/* Record address of incoming setup packet; resp. data packet. */
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);
+
+/* Initialise the setup addresses. Called before we send the first
+ * packet in a key exchange. If we are the initiator, as a result of
+ * resolve completing (or being determined not to be relevant) or an
+ * incoming PROD; if we are the responder, as a result of the MSG1. */
static bool_t transport_compute_setupinit_peers(struct site *st,
- const struct comm_addr *configured_addr /* 0 if none or not found */,
- const struct comm_addr *prod_hint_addr /* 0 if none */);
-static void transport_record_peer(struct site *st, transport_peers *peers,
- const struct comm_addr *addr, const char *m);
+ const struct comm_addr *configured_addrs /* 0 if none or not found */,
+ int n_configured_addrs /* 0 if none or not found */,
+ const struct comm_addr *incoming_packet_addr /* 0 if none */);
+
+/* Called if we are the responder in a key setup, when the resolve
+ * completes. transport_compute_setupinit_peers will hvae been called
+ * earlier. If _complete is called, we are still doing the key setup
+ * (and we should use the new values for both the rest of the key
+ * setup and the ongoing data exchange); if _tardy is called, the key
+ * setup is done (either completed or not) and only the data peers are
+ * relevant */
+static void transport_resolve_complete(struct site *st,
+ const struct comm_addr *addrs, int naddrs);
+static void transport_resolve_complete_tardy(struct site *st,
+ const struct comm_addr *addrs, int naddrs);
static void transport_xmit(struct site *st, transport_peers *peers,
struct buffer_if *buf, bool_t candebug);
/* configuration information */
string_t localname;
string_t remotename;
- bool_t peer_mobile; /* Mobile client support */
+ bool_t local_mobile, 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 */
+ cstring_t *addresses; /* DNS name or address(es) for bootstrapping, optional */
int remoteport; /* Port for bootstrapping, optional */
+ uint32_t mtu_target;
struct netlink_if *netlink;
struct comm_if **comms;
int ncomms;
uint32_t state;
uint64_t now; /* Most recently seen time */
bool_t allow_send_prod;
+ int resolving_count;
+ int resolving_n_results_all;
+ int resolving_n_results_stored;
+ struct comm_addr resolving_results[MAX_PEER_ADDRS];
/* The currently established session */
struct data_key current;
timeout before we can listen for another setup packet); perhaps
we should keep a list of 'bad' sources for setup packets. */
uint32_t remote_capabilities;
+ uint16_t remote_adv_mtu;
struct transform_if *chosen_transform;
uint32_t setup_session_id;
transport_peers setup_peers;
struct transform_inst_if *new_transform; /* For key setup/verify */
};
+static uint32_t event_log_priority(struct site *st, uint32_t event)
+{
+ if (!(event&st->log_events))
+ return 0;
+ switch(event) {
+ case LOG_UNEXPECTED: return M_INFO;
+ case LOG_SETUP_INIT: return M_INFO;
+ case LOG_SETUP_TIMEOUT: return M_NOTICE;
+ case LOG_ACTIVATE_KEY: return M_INFO;
+ case LOG_TIMEOUT_KEY: return M_INFO;
+ case LOG_SEC: return M_SECURITY;
+ case LOG_STATE: return M_DEBUG;
+ case LOG_DROP: return M_DEBUG;
+ case LOG_DUMP: return M_DEBUG;
+ case LOG_ERROR: return M_ERR;
+ case LOG_PEER_ADDRS: return M_DEBUG;
+ default: return M_ERR;
+ }
+}
+
+static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
+FORMAT(printf,3,0);
+static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
+{
+ uint32_t class;
+
+ class=event_log_priority(st, event);
+ if (class) {
+ slilog_part(st->log,class,"%s: ",st->tunname);
+ vslilog_part(st->log,class,msg,ap);
+ slilog_part(st->log,class,"\n");
+ }
+}
+
static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
FORMAT(printf,3,4);
static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
{
va_list ap;
- char buf[240];
- uint32_t class;
-
va_start(ap,msg);
+ vslog(st,event,msg,ap);
+ va_end(ap);
+}
- if (event&st->log_events) {
- switch(event) {
- case LOG_UNEXPECTED: class=M_INFO; break;
- case LOG_SETUP_INIT: class=M_INFO; break;
- case LOG_SETUP_TIMEOUT: class=M_NOTICE; break;
- case LOG_ACTIVATE_KEY: class=M_INFO; break;
- case LOG_TIMEOUT_KEY: class=M_INFO; break;
- case LOG_SEC: class=M_SECURITY; break;
- case LOG_STATE: class=M_DEBUG; break;
- 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 logtimeout(struct site *st, const char *fmt, ...)
+FORMAT(printf,2,3);
+static void logtimeout(struct site *st, const char *fmt, ...)
+{
+ uint32_t class=event_log_priority(st,LOG_SETUP_TIMEOUT);
+ if (!class)
+ return;
- vsnprintf(buf,sizeof(buf),msg,ap);
- slilog(st->log,class,"%s: %s",st->tunname,buf);
+ va_list ap;
+ va_start(ap,fmt);
+
+ slilog_part(st->log,class,"%s: ",st->tunname);
+ vslilog_part(st->log,class,fmt,ap);
+
+ const char *delim;
+ int i;
+ for (i=0, delim=" (tried ";
+ i<st->setup_peers.npeers;
+ i++, delim=", ") {
+ transport_peer *peer=&st->setup_peers.peers[i];
+ const char *s=comm_addr_to_string(&peer->addr);
+ slilog_part(st->log,class,"%s%s",delim,s);
}
+
+ slilog_part(st->log,class,")\n");
va_end(ap);
}
const struct comm_addr *prod_hint);
static void enter_state_run(struct site *st);
static bool_t enter_state_resolve(struct site *st);
+static void decrement_resolving_count(struct site *st, int by);
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);
type=buf_unprepend_uint32((b)); \
if (type!=(t)) return False; } while(0)
+static _Bool type_is_msg34(uint32_t type)
+{
+ return
+ type == LABEL_MSG3 ||
+ type == LABEL_MSG3BIS ||
+ type == LABEL_MSG4;
+}
+
struct parsedname {
int32_t len;
uint8_t *name;
struct parsedname remote;
struct parsedname local;
uint32_t remote_capabilities;
+ uint16_t remote_mtu;
int capab_transformnum;
uint8_t *nR;
uint8_t *nL;
assert(st->sharedsecretlen);
if (st->sharedsecretlen > st->sharedsecretallocd) {
st->sharedsecretallocd=st->sharedsecretlen;
- st->sharedsecret=realloc(st->sharedsecret,st->sharedsecretallocd);
+ st->sharedsecret=safe_realloc_ary(st->sharedsecret,1,
+ st->sharedsecretallocd,
+ "site:sharedsecret");
}
- if (!st->sharedsecret) fatal_perror("site:sharedsecret");
/* Generate the shared key */
st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
buf_append_uint32(&st->buffer,st->local_capabilities);
}
+ if (type_is_msg34(type)) {
+ buf_append_uint16(&st->buffer,st->mtu_target);
+ }
append_string_xinfo_done(&st->buffer,&xia);
buf_append_string(&st->buffer,st->remotename);
- memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN);
+ BUF_ADD_OBJ(append,&st->buffer,st->localN);
if (type==LABEL_MSG1) return True;
- memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN);
+ BUF_ADD_OBJ(append,&st->buffer,st->remoteN);
if (type==LABEL_MSG2) return True;
if (hacky_par_mid_failnow()) return False;
CHECK_TYPE(msg,type);
if (!unpick_name(msg,&m->remote)) return False;
m->remote_capabilities=0;
+ m->remote_mtu=0;
if (m->remote.extrainfo.size) {
CHECK_AVAIL(&m->remote.extrainfo,4);
m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
}
+ if (type_is_msg34(type) && m->remote.extrainfo.size) {
+ CHECK_AVAIL(&m->remote.extrainfo,2);
+ m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
+ }
if (!unpick_name(msg,&m->local)) return False;
if (type==LABEL_PROD) {
CHECK_EMPTY(msg);
process an incoming MSG1, and that the MSG1 has correct values
of A and B. */
- transport_record_peer(st,&st->setup_peers,src,"msg1");
st->setup_session_id=m->source;
st->remote_capabilities=m->remote_capabilities;
memcpy(st->remoteN,m->nR,NONCELEN);
"site:MSG3");
}
+static bool_t process_msg3_msg4(struct site *st, struct msg *m)
+{
+ uint8_t *hash;
+ void *hst;
+
+ /* Check signature and store g^x mod m */
+ hash=safe_malloc(st->hash->len, "process_msg3_msg4");
+ hst=st->hash->init();
+ st->hash->update(hst,m->hashstart,m->hashlen);
+ st->hash->final(hst,hash);
+ /* Terminate signature with a '0' - cheating, but should be ok */
+ m->sig[m->siglen]=0;
+ if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
+ slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
+ free(hash);
+ return False;
+ }
+ free(hash);
+
+ st->remote_adv_mtu=m->remote_mtu;
+
+ return True;
+}
+
static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
const struct comm_addr *src, uint32_t msgtype)
{
struct msg m;
- uint8_t *hash;
- void *hst;
cstring_t err;
assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
transform_found:
st->chosen_transform=ti;
- /* Check signature and store g^x mod m */
- hash=safe_malloc(st->hash->len, "process_msg3");
- hst=st->hash->init();
- st->hash->update(hst,m.hashstart,m.hashlen);
- st->hash->final(hst,hash);
- /* Terminate signature with a '0' - cheating, but should be ok */
- m.sig[m.siglen]=0;
- if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
- slog(st,LOG_SEC,"msg3 signature failed check!");
- free(hash);
+ if (!process_msg3_msg4(st,&m))
return False;
- }
- free(hash);
/* Terminate their DH public key with a '0' */
m.pk[m.pklen]=0;
const struct comm_addr *src)
{
struct msg m;
- uint8_t *hash;
- void *hst;
cstring_t err;
if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
return False;
}
- /* Check signature and store g^x mod m */
- hash=safe_malloc(st->hash->len, "process_msg4");
- hst=st->hash->init();
- st->hash->update(hst,m.hashstart,m.hashlen);
- st->hash->final(hst,hash);
- /* Terminate signature with a '0' - cheating, but should be ok */
- m.sig[m.siglen]=0;
- if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
- slog(st,LOG_SEC,"msg4 signature failed check!");
- free(hash);
+ if (!process_msg3_msg4(st,&m))
return False;
- }
- free(hash);
/* Terminate their DH public key with a '0' */
m.pk[m.pklen]=0;
st->retries--;
return True;
} else if (st->state==SITE_SENTMSG5) {
- slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key");
+ logtimeout(st,"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 */
enter_state_wait(st);
return False;
} else {
- slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet "
+ logtimeout(st,"timed out sending key setup packet "
"(in state %s)",state_name(st->state));
enter_state_wait(st);
return False;
}
}
-static void site_resolve_callback(void *sst, struct in_addr *address)
+static void site_resolve_callback(void *sst, const struct comm_addr *addrs,
+ int stored_naddrs, int all_naddrs,
+ const char *address, const char *failwhy)
{
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) {
- 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;
+ if (!stored_naddrs) {
+ slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy);
} else {
- slog(st,LOG_ERROR,"resolution of %s failed",st->address);
- ca_use=0;
+ slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s",
+ address, all_naddrs, comm_addr_to_string(&addrs[0]));;
+
+ int space=st->transport_peers_max-st->resolving_n_results_stored;
+ int n_tocopy=MIN(stored_naddrs,space);
+ COPY_ARRAY(st->resolving_results + st->resolving_n_results_stored,
+ addrs,
+ n_tocopy);
+ st->resolving_n_results_stored += n_tocopy;
+ st->resolving_n_results_all += all_naddrs;
}
- if (transport_compute_setupinit_peers(st,ca_use,0)) {
- 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);
+
+ decrement_resolving_count(st,1);
+}
+
+static void decrement_resolving_count(struct site *st, int by)
+{
+ assert(st->resolving_count>0);
+ st->resolving_count-=by;
+
+ if (st->resolving_count)
+ return;
+
+ /* OK, we are done with them all. Handle combined results. */
+
+ const struct comm_addr *addrs=st->resolving_results;
+ int naddrs=st->resolving_n_results_stored;
+ assert(naddrs<=st->transport_peers_max);
+
+ if (naddrs) {
+ if (naddrs != st->resolving_n_results_all) {
+ slog(st,LOG_SETUP_INIT,"resolution of supplied addresses/names"
+ " yielded too many results (%d > %d), some ignored",
+ st->resolving_n_results_all, naddrs);
+ }
+ slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s",
+ naddrs, comm_addr_to_string(&addrs[0]));;
+ }
+
+ switch (st->state) {
+ case SITE_RESOLVE:
+ if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
+ 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);
+ }
+ break;
+ case SITE_SENTMSG1: case SITE_SENTMSG2:
+ case SITE_SENTMSG3: case SITE_SENTMSG4:
+ case SITE_SENTMSG5:
+ if (naddrs) {
+ /* We start using the address immediately for data too.
+ * It's best to store it in st->peers now because we might
+ * go via SENTMSG5, WAIT, and a MSG0, straight into using
+ * the new key (without updating the data peer addrs). */
+ transport_resolve_complete(st,addrs,naddrs);
+ } else if (st->local_mobile) {
+ /* We can't let this rest because we may have a peer
+ * address which will break in the future. */
+ slog(st,LOG_SETUP_INIT,"resolution failed: "
+ "abandoning key exchange");
+ enter_state_wait(st);
+ } else {
+ slog(st,LOG_SETUP_INIT,"resolution failed: "
+ " continuing to use source address of peer's packets"
+ " for key exchange and ultimately data");
+ }
+ break;
+ case SITE_RUN:
+ if (naddrs) {
+ slog(st,LOG_SETUP_INIT,"resolution completed tardily,"
+ " updating peer address(es)");
+ transport_resolve_complete_tardy(st,addrs,naddrs);
+ } else if (st->local_mobile) {
+ /* Not very good. We should queue (another) renegotiation
+ * so that we can update the peer address. */
+ st->key_renegotiate_time=st->now+st->wait_timeout;
+ } else {
+ slog(st,LOG_SETUP_INIT,"resolution failed: "
+ " continuing to use source address of peer's packets");
+ }
+ break;
+ case SITE_WAIT:
+ case SITE_STOP:
+ /* oh well */
+ break;
}
}
static bool_t initiate_key_setup(struct site *st, cstring_t reason,
const struct comm_addr *prod_hint)
{
+ /* Reentrancy hazard: can call enter_new_state/enter_state_* */
if (st->state!=SITE_RUN) return False;
slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
- if (st->address) {
- slog(st,LOG_SETUP_INIT,"resolving peer address");
+ if (st->addresses) {
+ slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
return enter_state_resolve(st);
- } else if (transport_compute_setupinit_peers(st,0,prod_hint)) {
+ } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
return enter_new_state(st,SITE_SENTMSG1);
}
slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
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");
+ /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
+ * But their mtu be unspecified, in which case we just use ours. */
+ uint32_t intersite_mtu=
+ MIN(st->mtu_target, st->remote_adv_mtu ?: ~(uint32_t)0);
+ st->netlink->set_mtu(st->netlink->st,intersite_mtu);
+
+ slog(st,LOG_ACTIVATE_KEY,"new key activated"
+ " (mtu ours=%"PRId32" theirs=%"PRId32" intersite=%"PRId32")",
+ st->mtu_target, st->remote_adv_mtu, intersite_mtu);
enter_state_run(st);
}
quality=LINK_QUALITY_UP;
else if (st->state==SITE_WAIT || st->state==SITE_STOP)
quality=LINK_QUALITY_DOWN;
- else if (st->address)
+ else if (st->addresses)
quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
else if (transport_peers_valid(&st->peers))
quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
st->setup_session_id=0;
transport_peers_clear(st,&st->setup_peers);
- memset(st->localN,0,NONCELEN);
- memset(st->remoteN,0,NONCELEN);
+ FILLZERO(st->localN);
+ FILLZERO(st->remoteN);
dispose_transform(&st->new_transform);
memset(st->dhsecret,0,st->dh->len);
memset(st->sharedsecret,0,st->sharedsecretlen);
set_link_quality(st);
}
+static bool_t ensure_resolving(struct site *st)
+{
+ /* Reentrancy hazard: may call site_resolve_callback and hence
+ * enter_new_state, enter_state_* and generate_msg*. */
+ if (st->resolving_count)
+ return True;
+
+ assert(st->addresses);
+
+ /* resolver->request might reentrantly call site_resolve_callback
+ * which will decrement st->resolving, so we need to increment it
+ * twice beforehand to prevent decrement from thinking we're
+ * finished, and decrement it ourselves. Alternatively if
+ * everything fails then there are no callbacks due and we simply
+ * set it to 0 and return false.. */
+ st->resolving_n_results_stored=0;
+ st->resolving_n_results_all=0;
+ st->resolving_count+=2;
+ const char **addrp=st->addresses;
+ const char *address;
+ bool_t anyok=False;
+ for (; (address=*addrp++); ) {
+ bool_t ok = st->resolver->request(st->resolver->st,address,
+ st->remoteport,st->comms[0],
+ site_resolve_callback,st);
+ if (ok)
+ st->resolving_count++;
+ anyok|=ok;
+ }
+ if (!anyok) {
+ st->resolving_count=0;
+ return False;
+ }
+ decrement_resolving_count(st,2);
+ return True;
+}
+
static bool_t enter_state_resolve(struct site *st)
{
+ /* Reentrancy hazard! See ensure_resolving. */
state_assert(st,st->state==SITE_RUN);
slog(st,LOG_STATE,"entering state RESOLVE");
st->state=SITE_RESOLVE;
- st->resolver->request(st->resolver->st,st->address,
- site_resolve_callback,st);
- return True;
+ return ensure_resolving(st);
}
static bool_t enter_new_state(struct site *st, uint32_t next)
{
struct site *st=sst;
- *nfds_io=0; /* We don't use any file descriptors */
+ BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
st->now=*now;
/* Work out when our next timeout is. The earlier of 'timeout' or
if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
st->state==SITE_WAIT) {
/* We should definitely process it */
+ transport_compute_setupinit_peers(st,0,0,source);
if (process_msg1(st,buf,source,&named_msg)) {
slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
- enter_new_state(st,SITE_SENTMSG2);
+ bool_t entered=enter_new_state(st,SITE_SENTMSG2);
+ if (entered && st->addresses && st->local_mobile)
+ /* We must do this as the very last thing, because
+ the resolver callback might reenter us. */
+ ensure_resolving(st);
} else {
slog(st,LOG_ERROR,"failed to process incoming msg1");
}
"priority => use incoming msg1");
if (process_msg1(st,buf,source,&named_msg)) {
BUF_FREE(&st->buffer); /* Free our old message 1 */
+ transport_setup_msgok(st,source);
enter_new_state(st,SITE_SENTMSG2);
} else {
slog(st,LOG_ERROR,"failed to process an incoming "
because our peer's forgotten the key */
if (get_uint32(buf->start+4)==st->current.remote_session_id) {
bool_t initiated;
- initiated = initiate_key_setup(st,"received a NAK",0);
+ initiated = initiate_key_setup(st,"received a NAK",source);
if (!initiated) generate_send_prod(st,source);
} else {
slog(st,LOG_SEC,"bad incoming NAK");
send_msg7(st,"shutting down");
}
+static void site_childpersist_clearkeys(void *sst, uint32_t newphase)
+{
+ struct site *st=sst;
+ dispose_transform(&st->current.transform);
+ dispose_transform(&st->auxiliary_key.transform);
+ dispose_transform(&st->new_transform);
+ /* Not much point overwiting the signing key, since we loaded it
+ from disk, and it is only valid prospectively if at all,
+ anyway. */
+ /* XXX it would be best to overwrite the DH state, because that
+ _is_ relevant to forward secrecy. However we have no
+ convenient interface for doing that and in practice gmp has
+ probably dribbled droppings all over the malloc arena. A good
+ way to fix this would be to have a privsep child for asymmetric
+ crypto operations, but that's a task for another day. */
+}
+
static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
list_t *args)
{
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=
+ st->local_mobile=
dict_read_bool(dict,"local-mobile",False,"site",loc,False);
/* Sanity check (which also allows the 'sites' file to include
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)
+ if (st->peer_mobile != st->local_mobile)
cfgfatal(loc,"site","site %s's peer-mobile=%d"
" but our local-mobile=%d\n",
- st->localname, st->peer_mobile, local_mobile);
+ st->localname, st->peer_mobile, st->local_mobile);
free(st);
return NULL;
}
- if (st->peer_mobile && local_mobile) {
+ if (st->peer_mobile && st->local_mobile) {
Message(M_WARNING,"site %s: site is mobile but so are we"
" -> ignoring this site\n", st->remotename);
free(st);
st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
- st->address=dict_read_string(dict, "address", False, "site", loc);
- if (st->address)
+ st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0);
+ if (st->addresses)
st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
else st->remoteport=0;
st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,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);
-#define DEFAULT(D) (st->peer_mobile || local_mobile \
+#define DEFAULT(D) (st->peer_mobile || st->local_mobile \
? DEFAULT_MOBILE_##D : DEFAULT_##D)
#define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
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->mtu_target= dict_read_number(dict,"mtu-target",False,"site",loc,0);
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);
+ const char *peerskey= st->peer_mobile
+ ? "mobile-peers-max" : "static-peers-max";
+ st->transport_peers_max= dict_read_number(
+ dict,peerskey,False,"site",loc, st->addresses ? 4 : 3);
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");
+ st->transport_peers_max>MAX_PEER_ADDRS) {
+ cfgfatal(loc,"site", "%s must be in range 1.."
+ STRING(MAX_PEER_ADDRS) "\n", peerskey);
}
if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
log_event_table,"site");
+ st->resolving_count=0;
st->allow_send_prod=0;
st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
/* 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");
+ register_for_poll(st, site_beforepoll, site_afterpoll, "site");
st->timeout=0;
st->remote_capabilities=0;
}
/* We need to register the remote networks with the netlink device */
- st->netlink->reg(st->netlink->st, site_outgoing, st);
+ uint32_t netlink_mtu; /* local virtual interface mtu */
+ st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
+ if (!st->mtu_target)
+ st->mtu_target=netlink_mtu;
for (i=0; i<st->ncomms; i++)
st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
enter_state_stop(st);
add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
+ add_hook(PHASE_CHILDPERSIST,site_childpersist_clearkeys,st);
return new_closure(&st->cl);
}
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));
+ i, comm_addr_to_string(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),
+ i, comm_addr_to_string(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;
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;
+static bool_t transport_peer_record_one(struct site *st, transport_peers *peers,
+ const struct comm_addr *ca,
+ const struct timeval *tv) {
+ /* returns false if output is full */
+ int search;
- for (slot=0; slot<peers->npeers; slot++)
- if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr)))
- goto found;
+ if (peers->npeers >= st->transport_peers_max)
+ return 0;
- changed=1;
- if (peers->npeers==st->transport_peers_max)
- slot=st->transport_peers_max;
- else
- slot=peers->npeers++;
+ for (search=0; search<peers->npeers; search++)
+ if (comm_addr_equal(&peers->peers[search].addr, ca))
+ return 1;
- found:
- peers->peers[slot].addr=*addr;
- peers->peers[slot].last=*tv_now;
+ peers->peers[peers->npeers].addr = *ca;
+ peers->peers[peers->npeers].last = *tv;
+ peers->npeers++;
+ return 1;
+}
- if (peers->npeers>1)
- qsort(peers->peers, peers->npeers,
- sizeof(*peers->peers), transport_peer_compar);
+static void transport_record_peers(struct site *st, transport_peers *peers,
+ const struct comm_addr *addrs, int naddrs,
+ const char *m) {
+ /* We add addrs into peers. The new entries end up at the front
+ * and displace entries towards the end (perhaps even off the
+ * end). Any existing matching entries are moved up to the front.
+ *
+ * Caller must first call transport_peers_expire. */
- if (changed || peers->npeers!=1)
- transport_peers_debug(st,peers,m, 1,addr,0);
- transport_peers_expire(st, peers);
+ if (naddrs==1 && peers->npeers>=1 &&
+ comm_addr_equal(&addrs[0], &peers->peers[0].addr)) {
+ /* optimisation, also avoids debug for trivial updates */
+ peers->peers[0].last = *tv_now;
+ return;
+ }
+
+ int old_npeers=peers->npeers;
+ transport_peer old_peers[old_npeers];
+ COPY_ARRAY(old_peers,peers->peers,old_npeers);
+
+ peers->npeers=0;
+ int i;
+ for (i=0; i<naddrs; i++) {
+ if (!transport_peer_record_one(st,peers, &addrs[i], tv_now))
+ break;
+ }
+ for (i=0; i<old_npeers; i++) {
+ const transport_peer *old=&old_peers[i];
+ if (!transport_peer_record_one(st,peers, &old->addr, &old->last))
+ break;
+ }
+
+ transport_peers_debug(st,peers,m, naddrs,addrs,0);
}
-static bool_t transport_compute_setupinit_peers(struct site *st,
- const struct comm_addr *configured_addr /* 0 if none or not found */,
- const struct comm_addr *prod_hint_addr /* 0 if none */) {
+static void transport_expire_record_peers(struct site *st,
+ transport_peers *peers,
+ const struct comm_addr *addrs,
+ int naddrs, const char *m) {
+ /* Convenience function */
+ transport_peers_expire(st,peers);
+ transport_record_peers(st,peers,addrs,naddrs,m);
+}
- if (!configured_addr && !prod_hint_addr &&
+static bool_t transport_compute_setupinit_peers(struct site *st,
+ const struct comm_addr *configured_addrs /* 0 if none or not found */,
+ int n_configured_addrs /* 0 if none or not found */,
+ const struct comm_addr *incoming_packet_addr /* 0 if none */) {
+ if (!n_configured_addrs && !incoming_packet_addr &&
!transport_peers_valid(&st->peers))
return False;
slog(st,LOG_SETUP_INIT,
- "using:%s%s %d old peer address(es)",
- configured_addr ? " configured address;" : "",
- prod_hint_addr ? " PROD hint address;" : "",
+ "using: %d configured addr(s);%s %d old peer addrs(es)",
+ n_configured_addrs,
+ incoming_packet_addr ? " incoming packet address;" : "",
st->peers.npeers);
- /* 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 address of the incoming PROD, or the existing data peer if
- * one exists; this is as desired. */
+ /* Non-mobile peers try addresses until one is plausible. The
+ * effect is that this code always tries first the configured
+ * address if supplied, or otherwise the address of the incoming
+ * PROD, or finally the existing data peer if one exists; this is
+ * as desired. */
transport_peers_copy(st,&st->setup_peers,&st->peers);
+ transport_peers_expire(st,&st->setup_peers);
- if (prod_hint_addr)
- transport_record_peer(st,&st->setup_peers,prod_hint_addr,"prod");
+ if (incoming_packet_addr)
+ transport_record_peers(st,&st->setup_peers,
+ incoming_packet_addr,1, "incoming");
- if (configured_addr)
- transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit");
+ if (n_configured_addrs)
+ transport_record_peers(st,&st->setup_peers,
+ configured_addrs,n_configured_addrs, "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");
+ transport_expire_record_peers(st,&st->setup_peers,a,1,"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");
+ transport_expire_record_peers(st,&st->peers,a,1,"datamsg");
}
static int transport_peers_valid(transport_peers *peers) {
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);
+ COPY_ARRAY(dst->peers, src->peers, dst->npeers);
transport_peers_debug(st,dst,"copy",
src->npeers, &src->peers->addr, sizeof(*src->peers));
}
+static void transport_resolve_complete(struct site *st,
+ const struct comm_addr *addrs,
+ int naddrs) {
+ transport_expire_record_peers(st,&st->peers,addrs,naddrs,
+ "resolved data");
+ transport_expire_record_peers(st,&st->setup_peers,addrs,naddrs,
+ "resolved setup");
+}
+
+static void transport_resolve_complete_tardy(struct site *st,
+ const struct comm_addr *addrs,
+ int naddrs) {
+ transport_expire_record_peers(st,&st->peers,addrs,naddrs,
+ "resolved tardily");
+}
+
+static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io,
+ unsigned mask,
+ const transport_peers *inp) {
+ /* out and in->peers may be the same region, or nonoverlapping */
+ const transport_peer *in=inp->peers;
+ int slot;
+ for (slot=0; slot<inp->npeers; slot++) {
+ if (!(mask & (1U << slot)))
+ continue;
+ if (!(out==in && slot==*nout_io))
+ COPY_OBJ(out[*nout_io], in[slot]);
+ (*nout_io)++;
+ }
+}
+
void transport_xmit(struct site *st, transport_peers *peers,
struct buffer_if *buf, bool_t candebug) {
int slot;
transport_peers_expire(st, peers);
+ unsigned failed=0; /* bitmask */
+ assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT);
+
+ int nfailed=0;
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);
+ bool_t ok =
+ peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
+ if (!ok) {
+ failed |= 1U << slot;
+ nfailed++;
+ }
+ if (ok && !st->peer_mobile)
+ break;
+ }
+ /* Now we need to demote/delete failing addrs: if we are mobile we
+ * merely demote them; otherwise we delete them. */
+ if (st->local_mobile) {
+ unsigned expected = ((1U << nfailed)-1) << (peers->npeers-nfailed);
+ /* `expected' has all the failures at the end already */
+ if (failed != expected) {
+ int fslot=0;
+ transport_peer failedpeers[nfailed];
+ transport_peers__copy_by_mask(failedpeers, &fslot, failed,peers);
+ assert(fslot == nfailed);
+ int wslot=0;
+ transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
+ assert(wslot+nfailed == peers->npeers);
+ COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
+ }
+ } else {
+ if (failed && peers->npeers > 1) {
+ int wslot=0;
+ transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
+ peers->npeers=wslot;
+ }
}
}
~ian / secnet.git / blobdiff