/***** 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;
struct random_if *random;
struct rsaprivkey_if *privkey;
struct rsapubkey_if *pubkey;
- struct transform_if *transform;
+ struct transform_if **transforms;
+ int ntransforms;
struct dh_if *dh;
struct hash_if *hash;
uint32_t index; /* Index of this site */
+ uint32_t local_capabilities;
int32_t setup_retries; /* How many times to send setup packets */
int32_t setup_retry_interval; /* Initial timeout for setup packets */
int32_t wait_timeout; /* How long to wait if setup unsuccessful */
after this time, initiate a new
key exchange */
- uint8_t *setupsig; /* Expected signature of incoming MSG1 packets */
- int32_t setupsiglen; /* Allows us to discard packets quickly if
- they are not for us */
bool_t setup_priority; /* Do we have precedence if both sites emit
message 1 simultaneously? */
uint32_t log_events;
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 */
+ 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
packet; we keep trying to continue the exchange, and have to
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;
+ struct transform_if *chosen_transform;
uint32_t setup_session_id;
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;
uint8_t *sharedsecret;
+ uint32_t sharedsecretlen, sharedsecretallocd;
struct transform_inst_if *new_transform; /* For key setup/verify */
};
}
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 is_transform_valid(struct transform_inst_if *transform)
+{
+ return transform && transform->valid(transform->st);
+}
+
+static bool_t current_valid(struct site *st)
+{
+ return is_transform_valid(st->current.transform);
+}
+
+#define DEFINE_CALL_TRANSFORM(fwdrev) \
+static int call_transform_##fwdrev(struct site *st, \
+ struct transform_inst_if *transform, \
+ struct buffer_if *buf, \
+ const char **errmsg) \
+{ \
+ if (!is_transform_valid(transform)) { \
+ *errmsg="transform not set up"; \
+ return 1; \
+ } \
+ return transform->fwdrev(transform->st,buf,errmsg); \
+}
+
+DEFINE_CALL_TRANSFORM(forwards)
+DEFINE_CALL_TRANSFORM(reverse)
+
+static void dispose_transform(struct transform_inst_if **transform_var)
+{
+ struct transform_inst_if *transform=*transform_var;
+ if (transform) {
+ transform->delkey(transform->st);
+ transform->destroy(transform->st);
+ }
+ *transform_var = 0;
+}
#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)
type=buf_unprepend_uint32((b)); \
if (type!=(t)) return False; } while(0)
+struct parsedname {
+ int32_t len;
+ uint8_t *name;
+ struct buffer_if extrainfo;
+};
+
struct msg {
uint8_t *hashstart;
uint32_t dest;
uint32_t source;
- int32_t remlen;
- uint8_t *remote;
- int32_t loclen;
- uint8_t *local;
+ struct parsedname remote;
+ struct parsedname local;
+ uint32_t remote_capabilities;
+ int capab_transformnum;
uint8_t *nR;
uint8_t *nL;
int32_t pklen;
char *sig;
};
+static void set_new_transform(struct site *st, char *pk)
+{
+ /* Make room for the shared key */
+ st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
+ assert(st->sharedsecretlen);
+ if (st->sharedsecretlen > st->sharedsecretallocd) {
+ st->sharedsecretallocd=st->sharedsecretlen;
+ st->sharedsecret=realloc(st->sharedsecret,st->sharedsecretallocd);
+ }
+ if (!st->sharedsecret) fatal_perror("site:sharedsecret");
+
+ /* Generate the shared key */
+ st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
+ st->sharedsecret,st->sharedsecretlen);
+
+ /* Set up the transform */
+ struct transform_if *generator=st->chosen_transform;
+ struct transform_inst_if *generated=generator->create(generator->st);
+ generated->setkey(generated->st,st->sharedsecret,
+ st->sharedsecretlen,st->setup_priority);
+ dispose_transform(&st->new_transform);
+ st->new_transform=generated;
+
+ slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
+ " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
+ st->chosen_transform->capab_transformnum,
+ st->local_capabilities, st->remote_capabilities);
+}
+
+struct xinfoadd {
+ int32_t lenpos, afternul;
+};
+static void append_string_xinfo_start(struct buffer_if *buf,
+ struct xinfoadd *xia,
+ const char *str)
+ /* Helps construct one of the names with additional info as found
+ * in MSG1..4. Call this function first, then append all the
+ * desired extra info (not including the nul byte) to the buffer,
+ * then call append_string_xinfo_done. */
+{
+ xia->lenpos = buf->size;
+ buf_append_string(buf,str);
+ buf_append_uint8(buf,0);
+ xia->afternul = buf->size;
+}
+static void append_string_xinfo_done(struct buffer_if *buf,
+ struct xinfoadd *xia)
+{
+ /* we just need to adjust the string length */
+ if (buf->size == xia->afternul) {
+ /* no extra info, strip the nul too */
+ buf_unappend_uint8(buf);
+ } else {
+ put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
+ }
+}
+
/* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
out using a transform of config data supplied by netlink */
static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
(type==LABEL_MSG1?0:st->setup_session_id));
buf_append_uint32(&st->buffer,st->index);
buf_append_uint32(&st->buffer,type);
- buf_append_string(&st->buffer,st->localname);
+
+ struct xinfoadd xia;
+ append_string_xinfo_start(&st->buffer,&xia,st->localname);
+ if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
+ buf_append_uint32(&st->buffer,st->local_capabilities);
+ }
+ append_string_xinfo_done(&st->buffer,&xia);
+
buf_append_string(&st->buffer,st->remotename);
memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN);
if (type==LABEL_MSG1) return True;
if (hacky_par_mid_failnow()) return False;
+ if (type==LABEL_MSG3BIS)
+ buf_append_uint8(&st->buffer,st->chosen_transform->capab_transformnum);
+
dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
buf_append_string(&st->buffer,dhpub);
free(dhpub);
return True;
}
+static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
+{
+ CHECK_AVAIL(msg,2);
+ nm->len=buf_unprepend_uint16(msg);
+ CHECK_AVAIL(msg,nm->len);
+ nm->name=buf_unprepend(msg,nm->len);
+ uint8_t *nul=memchr(nm->name,0,nm->len);
+ if (!nul) {
+ buffer_readonly_view(&nm->extrainfo,0,0);
+ } else {
+ buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
+ nm->len=nul-nm->name;
+ }
+ return True;
+}
+
static bool_t unpick_msg(struct site *st, uint32_t type,
struct buffer_if *msg, struct msg *m)
{
+ m->capab_transformnum=-1;
m->hashstart=msg->start;
CHECK_AVAIL(msg,4);
m->dest=buf_unprepend_uint32(msg);
CHECK_AVAIL(msg,4);
m->source=buf_unprepend_uint32(msg);
CHECK_TYPE(msg,type);
- CHECK_AVAIL(msg,2);
- m->remlen=buf_unprepend_uint16(msg);
- CHECK_AVAIL(msg,m->remlen);
- m->remote=buf_unprepend(msg,m->remlen);
- CHECK_AVAIL(msg,2);
- m->loclen=buf_unprepend_uint16(msg);
- CHECK_AVAIL(msg,m->loclen);
- m->local=buf_unprepend(msg,m->loclen);
+ if (!unpick_name(msg,&m->remote)) return False;
+ m->remote_capabilities=0;
+ if (m->remote.extrainfo.size) {
+ CHECK_AVAIL(&m->remote.extrainfo,4);
+ m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
+ }
+ if (!unpick_name(msg,&m->local)) return False;
CHECK_AVAIL(msg,NONCELEN);
m->nR=buf_unprepend(msg,NONCELEN);
if (type==LABEL_MSG1) {
CHECK_EMPTY(msg);
return True;
}
+ if (type==LABEL_MSG3BIS) {
+ CHECK_AVAIL(msg,1);
+ m->capab_transformnum = buf_unprepend_uint8(msg);
+ } else {
+ m->capab_transformnum = CAPAB_TRANSFORMNUM_ANCIENT;
+ }
CHECK_AVAIL(msg,2);
m->pklen=buf_unprepend_uint16(msg);
CHECK_AVAIL(msg,m->pklen);
return True;
}
+static bool_t name_matches(const struct parsedname *nm, const char *expected)
+{
+ int expected_len=strlen(expected);
+ return
+ nm->len == expected_len &&
+ !memcmp(nm->name, expected, expected_len);
+}
+
static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
cstring_t *error)
{
/* Check that the site names and our nonce have been sent
back correctly, and then store our peer's nonce. */
- if (memcmp(m->remote,st->remotename,strlen(st->remotename)!=0)) {
+ if (!name_matches(&m->remote,st->remotename)) {
*error="wrong remote site name";
return False;
}
- if (memcmp(m->local,st->localname,strlen(st->localname)!=0)) {
+ if (!name_matches(&m->local,st->localname)) {
*error="wrong local site name";
return False;
}
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;
}
- if (type==LABEL_MSG3) return True;
+ /* MSG3 has complicated rules about capabilities, which are
+ * handled in process_msg3. */
+ if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
+ if (m->remote_capabilities!=st->remote_capabilities) {
+ *error="remote capabilities changed";
+ return False;
+ }
if (type==LABEL_MSG4) return True;
*error="unknown message type";
return False;
}
static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
- const struct comm_addr *src)
+ const struct comm_addr *src, struct msg *m)
{
- struct msg m;
-
/* We've already determined we're in an appropriate state to
process an incoming MSG1, and that the MSG1 has correct values
of A and B. */
- if (!unpick_msg(st,LABEL_MSG1,msg1,&m)) return False;
-
transport_record_peer(st,&st->setup_peers,src,"msg1");
- st->setup_session_id=m.source;
- memcpy(st->remoteN,m.nR,NONCELEN);
+ st->setup_session_id=m->source;
+ st->remote_capabilities=m->remote_capabilities;
+ memcpy(st->remoteN,m->nR,NONCELEN);
return True;
}
return False;
}
st->setup_session_id=m.source;
+ st->remote_capabilities=m.remote_capabilities;
+
+ /* Select the transform to use */
+
+ uint32_t remote_transforms = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
+ if (!remote_transforms)
+ /* old secnets only had this one transform */
+ remote_transforms = 1UL << CAPAB_TRANSFORMNUM_ANCIENT;
+
+ struct transform_if *ti;
+ int i;
+ for (i=0; i<st->ntransforms; i++) {
+ ti=st->transforms[i];
+ if ((1UL << ti->capab_transformnum) & remote_transforms)
+ goto transform_found;
+ }
+ slog(st,LOG_ERROR,"no transforms in common"
+ " (us %#"PRIx32"; them: %#"PRIx32")",
+ st->local_capabilities & CAPAB_TRANSFORM_MASK,
+ remote_transforms);
+ return False;
+ transform_found:
+ st->chosen_transform=ti;
+
memcpy(st->remoteN,m.nR,NONCELEN);
return True;
}
/* Now we have our nonce and their nonce. Think of a secret key,
and create message number 3. */
st->random->generate(st->random->st,st->dh->len,st->dhsecret);
- return generate_msg(st,LABEL_MSG3,"site:MSG3");
+ return generate_msg(st,
+ (st->remote_capabilities & CAPAB_TRANSFORM_MASK
+ ? LABEL_MSG3BIS : LABEL_MSG3),
+ "site:MSG3");
}
static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
- const struct comm_addr *src)
+ const struct comm_addr *src, uint32_t msgtype)
{
struct msg m;
uint8_t *hash;
void *hst;
cstring_t err;
- if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False;
- if (!check_msg(st,LABEL_MSG3,&m,&err)) {
+ assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
+
+ if (!unpick_msg(st,msgtype,msg3,&m)) return False;
+ if (!check_msg(st,msgtype,&m,&err)) {
slog(st,LOG_SEC,"msg3: %s",err);
return False;
}
+ uint32_t capab_adv_late = m.remote_capabilities
+ & ~st->remote_capabilities & CAPAB_EARLY;
+ if (capab_adv_late) {
+ slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
+ " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
+ capab_adv_late, st->remote_capabilities, m.remote_capabilities);
+ return False;
+ }
+ st->remote_capabilities|=m.remote_capabilities;
+
+ struct transform_if *ti;
+ int i;
+ for (i=0; i<st->ntransforms; i++) {
+ ti=st->transforms[i];
+ if (ti->capab_transformnum == m.capab_transformnum)
+ goto transform_found;
+ }
+ slog(st,LOG_SEC,"peer chose unknown-to-us transform %d!",
+ m.capab_transformnum);
+ return False;
+ transform_found:
+ st->chosen_transform=ti;
/* Check signature and store g^x mod m */
hash=safe_malloc(st->hash->len, "process_msg3");
/* Invent our DH secret key */
st->random->generate(st->random->st,st->dh->len,st->dhsecret);
- /* Generate the shared key */
- st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
- st->sharedsecret,st->transform->keylen);
-
- /* Set up the transform */
- st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
- st->transform->keylen);
+ /* Generate the shared key and set up the transform */
+ set_new_transform(st,m.pk);
return True;
}
/* Terminate their DH public key with a '0' */
m.pk[m.pklen]=0;
- /* Generate the shared key */
- st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
- st->sharedsecret,st->transform->keylen);
- /* Set up the transform */
- st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
- st->transform->keylen);
+
+ /* Generate the shared key and set up the transform */
+ set_new_transform(st,m.pk);
return True;
}
BUF_ALLOC(&st->buffer,"site:MSG5");
/* We are going to add four words to the message */
- buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
+ buffer_init(&st->buffer,st->new_transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
buf_prepend_uint32(&st->buffer,LABEL_MSG5);
- st->new_transform->forwards(st->new_transform->st,&st->buffer,
- &transform_err);
+ if (call_transform_forwards(st,st->new_transform,
+ &st->buffer,&transform_err))
+ return False;
buf_prepend_uint32(&st->buffer,LABEL_MSG5);
buf_prepend_uint32(&st->buffer,st->index);
buf_prepend_uint32(&st->buffer,st->setup_session_id);
}
static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
- const struct comm_addr *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 (call_transform_reverse(st,transform,msg5,&transform_err)) {
/* There's a problem */
slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
return False;
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;
BUF_ALLOC(&st->buffer,"site:MSG6");
/* We are going to add four words to the message */
- buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
+ buffer_init(&st->buffer,transform->max_start_pad+(4*4));
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
- st->new_transform->forwards(st->new_transform->st,&st->buffer,
- &transform_err);
+ int problem = call_transform_forwards(st,transform,
+ &st->buffer,&transform_err);
+ assert(!problem);
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)
+{
+ if (!is_transform_valid(st->new_transform))
+ return False;
+ create_msg6(st,st->new_transform,st->setup_session_id);
st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
return True;
}
if (!unpick_msg0(st,msg6,&m)) return False;
- if (st->new_transform->reverse(st->new_transform->st,
- msg6,&transform_err)) {
+ if (call_transform_reverse(st,st->new_transform,msg6,&transform_err)) {
/* There's a problem */
slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
return False;
return True;
}
-static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0)
+static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
+ const struct comm_addr *src)
{
- cstring_t transform_err;
+ cstring_t transform_err, auxkey_err, newkey_err="n/a";
struct msg0 m;
uint32_t problem;
if (!unpick_msg0(st,msg0,&m)) return False;
- problem = st->current_transform->reverse(st->current_transform->st,
- msg0,&transform_err);
- if (!problem) return True;
+ /* Keep a copy so we can try decrypting it with multiple keys */
+ buffer_copy(&st->scratch, msg0);
- slog(st,LOG_SEC,"transform: %s",transform_err);
+ problem = call_transform_reverse(st,st->current.transform,
+ 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 (problem==2)
+ goto skew;
+
+ buffer_copy(msg0, &st->scratch);
+ problem = call_transform_reverse(st,st->auxiliary_key.transform,
+ 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 (problem==2)
+ goto skew;
+
+ if (st->state==SITE_SENTMSG5) {
+ buffer_copy(msg0, &st->scratch);
+ problem = call_transform_reverse(st,st->new_transform,
+ msg0,&newkey_err);
+ if (!problem) {
+ /* 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 */
+ }
+ if (problem==2)
+ goto skew;
+ }
+
+ 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");
+ send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
+ return False;
+
+ skew:
+ slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
return False;
}
{
uint32_t type;
- if (!decrypt_msg0(st,msg0))
+ if (!decrypt_msg0(st,msg0,src))
return False;
CHECK_AVAIL(msg0,4);
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;
case LABEL_MSG9:
/* Deliver to netlink layer */
static void dump_packet(struct site *st, struct buffer_if *buf,
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));
- uint32_t msgtype=ntohl(*(uint32_t *)(buf->start+8));
+ uint32_t dest=get_uint32(buf->start);
+ uint32_t source=get_uint32(buf->start+4);
+ uint32_t msgtype=get_uint32(buf->start+8);
if (st->log_events & LOG_DUMP)
slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:",
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;
+ dispose_transform(&st->new_transform);
+
+ 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));
{
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;
+ dispose_transform(&st->new_transform);
- 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;
transport_peers_copy(st,&st->peers,&st->setup_peers);
- st->remote_session_id=st->setup_session_id;
+ 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 (st->current_valid) {
+ if (!is_transform_valid(key->transform)) return;
+ if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
+ dispose_transform(&key->transform);
+ key->key_timeout=0;
+}
+
+static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
+{
+ 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);
- st->new_transform->delkey(st->new_transform->st);
+ delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
+ dispose_transform(&st->new_transform);
}
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;
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);
+ dispose_transform(&st->new_transform);
memset(st->dhsecret,0,st->dh->len);
- memset(st->sharedsecret,0,st->transform->keylen);
+ memset(st->sharedsecret,0,st->sharedsecretlen);
set_link_quality(st);
}
{
cstring_t transform_err;
- if (st->current_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));
+ buffer_init(&st->buffer,st->current.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->buffer, &transform_err);
+ if (call_transform_forwards(st, st->current.transform,
+ &st->buffer, &transform_err))
+ goto free_out;
buf_prepend_uint32(&st->buffer,LABEL_MSG0);
buf_prepend_uint32(&st->buffer,st->index);
- buf_prepend_uint32(&st->buffer,st->remote_session_id);
+ buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
transport_xmit(st,&st->peers,&st->buffer,True);
BUF_FREE(&st->buffer);
+ free_out:
return True;
}
return False;
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 && transport_peers_valid(&st->peers)) {
+ 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,
- buf, &transform_err);
+ if (call_transform_forwards(st, st->current.transform,
+ buf, &transform_err))
+ goto free_out;
buf_prepend_uint32(buf,LABEL_MSG0);
buf_prepend_uint32(buf,st->index);
- buf_prepend_uint32(buf,st->remote_session_id);
+ buf_prepend_uint32(buf,st->current.remote_session_id);
transport_xmit(st,&st->peers,buf,False);
}
+ free_out:
BUF_FREE(buf);
return;
}
initiate_key_setup(st,"outgoing packet");
}
+static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
+ uint32_t type, struct msg *m)
+ /* For packets which are identified by the local and remote names.
+ * If it has our name and our peer's name in it it's for us. */
+{
+ struct buffer_if buf[1];
+ buffer_readonly_clone(buf,buf_in);
+ return unpick_msg(st,type,buf,m)
+ && name_matches(&m->remote,st->remotename)
+ && name_matches(&m->local,st->localname);
+}
+
/* 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,
if (buf->size < 12) return False;
- uint32_t dest=ntohl(*(uint32_t *)buf->start);
-
- if (dest==0) {
- /* It could be for any site - it should have LABEL_MSG1 and
- might have our name and our peer's name in it */
- if (buf->size<(st->setupsiglen+8+NONCELEN)) return False;
- if (memcmp(buf->start+8,st->setupsig,st->setupsiglen)==0) {
- /* It's addressed to us. Decide what to do about it. */
- dump_packet(st,buf,source,True);
- if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
- st->state==SITE_WAIT) {
- /* We should definitely process it */
- if (process_msg1(st,buf,source)) {
- slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
+ uint32_t dest=get_uint32(buf->start);
+ uint32_t msgtype=get_uint32(buf->start+8);
+ struct msg named_msg;
+
+ if (msgtype==LABEL_MSG1) {
+ if (!named_for_us(st,buf,msgtype,&named_msg))
+ return False;
+ /* It's a MSG1 addressed to us. Decide what to do about it. */
+ dump_packet(st,buf,source,True);
+ if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
+ st->state==SITE_WAIT) {
+ /* We should definitely process it */
+ if (process_msg1(st,buf,source,&named_msg)) {
+ slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
+ enter_new_state(st,SITE_SENTMSG2);
+ } else {
+ slog(st,LOG_ERROR,"failed to process incoming msg1");
+ }
+ BUF_FREE(buf);
+ return True;
+ } else if (st->state==SITE_SENTMSG1) {
+ /* We've just sent a message 1! They may have crossed on
+ the wire. If we have priority then we ignore the
+ incoming one, otherwise we process it as usual. */
+ if (st->setup_priority) {
+ BUF_FREE(buf);
+ slog(st,LOG_DUMP,"crossed msg1s; we are higher "
+ "priority => ignore incoming msg1");
+ return True;
+ } else {
+ slog(st,LOG_DUMP,"crossed msg1s; we are lower "
+ "priority => use incoming msg1");
+ if (process_msg1(st,buf,source,&named_msg)) {
+ BUF_FREE(&st->buffer); /* Free our old message 1 */
enter_new_state(st,SITE_SENTMSG2);
} else {
- slog(st,LOG_ERROR,"failed to process incoming msg1");
+ slog(st,LOG_ERROR,"failed to process an incoming "
+ "crossed msg1 (we have low priority)");
}
BUF_FREE(buf);
return True;
- } else if (st->state==SITE_SENTMSG1) {
- /* We've just sent a message 1! They may have crossed on
- the wire. If we have priority then we ignore the
- incoming one, otherwise we process it as usual. */
- if (st->setup_priority) {
- BUF_FREE(buf);
- slog(st,LOG_DUMP,"crossed msg1s; we are higher "
- "priority => ignore incoming msg1");
- return True;
- } else {
- slog(st,LOG_DUMP,"crossed msg1s; we are lower "
- "priority => use incoming msg1");
- if (process_msg1(st,buf,source)) {
- BUF_FREE(&st->buffer); /* Free our old message 1 */
- enter_new_state(st,SITE_SENTMSG2);
- } else {
- slog(st,LOG_ERROR,"failed to process an incoming "
- "crossed msg1 (we have low priority)");
- }
- BUF_FREE(buf);
- return True;
- }
}
- /* The message 1 was received at an unexpected stage of the
- key setup. XXX POLICY - what do we do? */
- slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
- BUF_FREE(buf);
- return True;
}
- return False; /* Not for us. */
+ /* The message 1 was received at an unexpected stage of the
+ key setup. XXX POLICY - what do we do? */
+ slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
+ BUF_FREE(buf);
+ return True;
}
if (dest==st->index) {
/* Explicitly addressed to us */
- uint32_t msgtype=ntohl(get_uint32(buf->start+8));
if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True);
switch (msgtype) {
- case 0: /* NAK */
+ case LABEL_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");
}
break;
case LABEL_MSG3:
+ case LABEL_MSG3BIS:
/* 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,msgtype)) {
transport_setup_msgok(st,source);
enter_new_state(st,SITE_SENTMSG4);
} else {
/* 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)) {
- transport_setup_msgok(st,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:
assert(index_sequence < 0xffffffffUL);
st->index = ++index_sequence;
+ st->local_capabilities = 0;
st->netlink=find_cl_if(dict,"link",CL_NETLINK,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;
- }
+#define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
+ list_t *things##_cfg=dict_lookup(dict,dictkey); \
+ if (!things##_cfg) \
+ cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
+ st->nthings=list_length(things##_cfg); \
+ st->things=safe_malloc_ary(sizeof(*st->things),st->nthings,dictkey "s"); \
+ assert(st->nthings); \
+ for (i=0; i<st->nthings; i++) { \
+ item_t *item=list_elem(things##_cfg,i); \
+ if (item->type!=t_closure) \
+ cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
+ closure_t *cl=item->data.closure; \
+ if (cl->type!=CL_TYPE) \
+ cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
+ st->things[i]=cl->interface; \
+ } \
+}while(0)
+
+ GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
else st->remoteport=0;
st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
- st->transform=
- find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc);
+ GET_CLOSURE_LIST("transform",transforms,ntransforms,CL_TRANSFORM);
st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
/* The information we expect to see in incoming messages of type 1 */
/* fixme: lots of unchecked overflows here, but the results are only
corrupted packets rather than undefined behaviour */
- st->setupsiglen=strlen(st->remotename)+strlen(st->localname)+8;
- st->setupsig=safe_malloc(st->setupsiglen,"site_apply");
- put_uint32(st->setupsig+0,LABEL_MSG1);
- put_uint16(st->setupsig+4,strlen(st->remotename));
- memcpy(&st->setupsig[6],st->remotename,strlen(st->remotename));
- put_uint16(st->setupsig+(6+strlen(st->remotename)),strlen(st->localname));
- memcpy(&st->setupsig[8+strlen(st->remotename)],st->localname,
- strlen(st->localname));
st->setup_priority=(strcmp(st->localname,st->remotename)>0);
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->remote_capabilities=0;
+ st->chosen_transform=0;
+ 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; \
+ st->sharedsecretlen=st->sharedsecretallocd=0;
+ st->sharedsecret=0;
+
+ /* We need to compute some properties of our comms and transports */
+#define COMPUTE_WORST(things,pad) \
+ int things##_worst_##pad=0; \
+ for (i=0; i<st->n##things; i++) { \
+ int thispad=st->things[i]->pad; \
+ if (thispad > things##_worst_##pad) \
+ things##_worst_##pad=thispad; \
+ }
+ COMPUTE_WORST(comms,min_start_pad)
+ COMPUTE_WORST(transforms,max_start_pad)
+
+ for (i=0; i<st->ntransforms; i++) {
+ struct transform_if *ti=st->transforms[i];
+ uint32_t capbit = 1UL << ti->capab_transformnum;
+ if (st->local_capabilities & capbit)
+ slog(st,LOG_ERROR,"transformnum capability bit"
+ " %d (%#"PRIx32") reused", ti->capab_transformnum, capbit);
+ st->local_capabilities |= capbit;
}
- 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)+
- worst_min_start_pad,
- st->transform->max_end_pad+worst_min_end_pad);
+ transforms_worst_max_start_pad+(4*4)+
+ comms_worst_min_start_pad);
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->new_transform=st->transform->create(st->transform->st);
+ st->current.transform=0;
+ st->auxiliary_key.transform=0;
+ st->new_transform=0;
+ st->auxiliary_is_new=0;
enter_state_stop(st);