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;
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 */
uint64_t timeout; /* Timeout for current state */
uint8_t *dhsecret;
uint8_t *sharedsecret;
- uint32_t sharedsecretlen;
+ uint32_t sharedsecretlen, sharedsecretallocd;
struct transform_inst_if *new_transform; /* For key setup/verify */
};
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)
+static void set_new_transform(struct site *st, char *pk)
{
- struct transform_if *generator=st->transform;
+ /* 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 {
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);
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_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);
}
/* MSG3 has complicated rules about capabilities, which are
* handled in process_msg3. */
- if (type==LABEL_MSG3) return True;
+ if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
if (m->remote_capabilities!=st->remote_capabilities) {
*error="remote capabilities changed";
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;
}
}
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");
hst=st->hash->init();
/* 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->sharedsecretlen);
-
- /* Set up the transform */
- set_new_transform(st);
+ /* 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->sharedsecretlen);
- /* Set up the transform */
- set_new_transform(st);
+
+ /* Generate the shared key and set up the transform */
+ set_new_transform(st,m.pk);
return True;
}
}
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 {
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);
st->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->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len;
- st->sharedsecret=safe_malloc(st->sharedsecretlen,"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)
/* 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);
+ 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);
~ian / secnet.git / blobdiff