#include "util.h"
#include "unaligned.h"
#include "magic.h"
+#include "pubkeys.h"
#define SETUP_BUFFER_LEN 2048
#define SITE_SENTMSG5 7
#define SITE_WAIT 8
+#define CASES_MSG3_KNOWN LABEL_MSG3: case LABEL_MSG3BIS
+
+struct msg;
+
int32_t site_max_start_pad = 4*4;
static cstring_t state_name(uint32_t state)
#define LOG_DUMP 0x00000100
#define LOG_ERROR 0x00000400
#define LOG_PEER_ADDRS 0x00000800
+#define LOG_SIGKEYS 0x00001000
static struct flagstr log_event_table[]={
{ "unexpected", LOG_UNEXPECTED },
{ "dump-packets", LOG_DUMP },
{ "errors", LOG_ERROR },
{ "peer-addrs", LOG_PEER_ADDRS },
+ { "sigkeys", LOG_SIGKEYS },
{ "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT|
- LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR },
+ LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR|LOG_SIGKEYS },
{ "all", 0xffffffff },
{ NULL, 0 }
};
struct resolver_if *resolver;
struct log_if *log;
struct random_if *random;
- struct rsaprivkey_if *privkey;
- struct rsapubkey_if *pubkey;
+ struct privcache_if *privkeys;
+ struct sigprivkey_if *privkey_fixed;
struct transform_if **transforms;
int ntransforms;
struct dh_if *dh;
- struct hash_if *hash;
uint32_t index; /* Index of this site */
+ uint32_t early_capabilities;
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 */
+ int32_t wait_timeout_mean; /* 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
key exchange */
- bool_t setup_priority; /* Do we have precedence if both sites emit
- message 1 simultaneously? */
+ bool_t our_name_later; /* our name > peer name */
uint32_t log_events;
/* runtime information */
int resolving_n_results_all;
int resolving_n_results_stored;
struct comm_addr resolving_results[MAX_PEER_ADDRS];
+ const char *peerkeys_path;
+ struct peer_keyset *peerkeys_current, *peerkeys_kex;
/* The currently established session */
struct data_key current;
case LOG_DUMP: return M_DEBUG;
case LOG_ERROR: return M_ERR;
case LOG_PEER_ADDRS: return M_DEBUG;
+ case LOG_SIGKEYS: return M_INFO;
default: return M_ERR;
}
}
+static uint32_t slog_start(struct site *st, uint32_t event)
+{
+ uint32_t class=event_log_priority(st, event);
+ if (class) {
+ slilog_part(st->log,class,"%s: ",st->tunname);
+ }
+ return class;
+}
+
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);
+ class=slog_start(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 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 bool_t enter_new_state(struct site *st,uint32_t next,
+ const struct msg *prompt
+ /* may be 0 for SENTMSG1 */);
static void enter_state_wait(struct site *st);
static void activate_new_key(struct site *st);
}
#define DEFINE_CALL_TRANSFORM(fwdrev) \
-static int call_transform_##fwdrev(struct site *st, \
+static transform_apply_return \
+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_apply_err; \
} \
return transform->fwdrev(transform->st,buf,errmsg); \
}
type=buf_unprepend_uint32((b)); \
if (type!=(t)) return False; } while(0)
+static _Bool type_is_msg23(uint32_t type)
+{
+ switch (type) {
+ case LABEL_MSG2: case CASES_MSG3_KNOWN: return True;
+ default: return False;
+ }
+}
static _Bool type_is_msg34(uint32_t type)
{
- return
- type == LABEL_MSG3 ||
- type == LABEL_MSG3BIS ||
- type == LABEL_MSG4;
+ switch (type) {
+ case CASES_MSG3_KNOWN: case LABEL_MSG4: return True;
+ default: return False;
+ }
}
struct parsedname {
int32_t pklen;
char *pk;
int32_t hashlen;
- int32_t siglen;
- char *sig;
+ struct alg_msg_data sig;
+ int n_pubkeys_accepted_nom; /* may be > MAX_SIG_KEYS ! */
+ const struct sigkeyid *pubkeys_accepted[MAX_SIG_KEYS];
+ int signing_key_index;
};
+static const struct sigkeyid keyid_zero;
+
+static int32_t wait_timeout(struct site *st) {
+ int32_t t = st->wait_timeout_mean;
+ int8_t factor;
+ if (t < INT_MAX/2) {
+ st->random->generate(st->random->st,sizeof(factor),&factor);
+ t += (t / 256) * factor;
+ }
+ return t;
+}
+
static _Bool set_new_transform(struct site *st, char *pk)
{
_Bool ok;
struct transform_if *generator=st->chosen_transform;
struct transform_inst_if *generated=generator->create(generator->st);
ok = generated->setkey(generated->st,st->sharedsecret,
- st->sharedsecretlen,st->setup_priority);
+ st->sharedsecretlen,st->our_name_later);
dispose_transform(&st->new_transform);
if (!ok) return False;
slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
" %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
- st->chosen_transform->capab_transformnum,
+ st->chosen_transform->capab_bit,
st->local_capabilities, st->remote_capabilities);
return True;
}
/* 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)
+static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what,
+ const struct msg *prompt
+ /* may be 0 for MSG1 */)
{
- void *hst;
- uint8_t *hash;
- string_t dhpub, sig;
+ string_t dhpub;
+ unsigned minor;
+ int ki;
st->retries=st->setup_retries;
BUF_ALLOC(&st->buffer,what);
struct xinfoadd xia;
append_string_xinfo_start(&st->buffer,&xia,st->localname);
- if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
+ if ((st->local_capabilities & st->early_capabilities) ||
+ (type != LABEL_MSG1)) {
buf_append_uint32(&st->buffer,st->local_capabilities);
}
if (type_is_msg34(type)) {
buf_append_uint16(&st->buffer,st->mtu_target);
}
+ if (type_is_msg23(type)) {
+ buf_append_uint8(&st->buffer,st->peerkeys_kex->nkeys);
+ for (ki=0; ki<st->peerkeys_kex->nkeys; ki++) {
+ struct peer_pubkey *pk = &st->peerkeys_kex->keys[ki];
+ BUF_ADD_OBJ(append,&st->buffer,pk->id);
+ }
+ }
+ struct sigprivkey_if *privkey=0;
+ if (type_is_msg34(type)) {
+ assert(prompt->n_pubkeys_accepted_nom>0);
+ for (ki=0;
+ ki<prompt->n_pubkeys_accepted_nom && ki<MAX_SIG_KEYS;
+ ki++) {
+ const struct sigkeyid *kid=prompt->pubkeys_accepted[ki];
+ if (st->privkeys) {
+ privkey=st->privkeys->lookup(st->privkeys->st,kid,st->log);
+ if (privkey) goto privkey_found;
+ } else {
+ if (sigkeyid_equal(&keyid_zero,kid)) {
+ privkey=st->privkey_fixed;
+ goto privkey_found;
+ }
+ }
+ }
+ uint32_t class = slog_start(st,LOG_ERROR);
+ if (class) {
+ slilog_part(st->log,class,"no suitable private key, peer wanted");
+ for (ki=0;
+ ki<prompt->n_pubkeys_accepted_nom && ki<MAX_SIG_KEYS;
+ ki++) {
+ slilog_part(st->log,class, " " SIGKEYID_PR_FMT,
+ SIGKEYID_PR_VAL(prompt->pubkeys_accepted[ki]));
+ }
+ if (prompt->n_pubkeys_accepted_nom > MAX_SIG_KEYS)
+ slilog_part(st->log,class," +%d",
+ prompt->n_pubkeys_accepted_nom - MAX_SIG_KEYS);
+ slilog_part(st->log,class,"\n");
+ }
+ return False;
+
+ privkey_found:
+ buf_append_uint8(&st->buffer,ki);
+ }
+
append_string_xinfo_done(&st->buffer,&xia);
buf_append_string(&st->buffer,st->remotename);
if (hacky_par_mid_failnow()) return False;
- if (type==LABEL_MSG3BIS)
- buf_append_uint8(&st->buffer,st->chosen_transform->capab_transformnum);
+ if (MSGMAJOR(type) == 3) do {
+ minor = MSGMINOR(type);
+ if (minor < 1) break;
+ buf_append_uint8(&st->buffer,st->chosen_transform->capab_bit);
+ } while (0);
dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
buf_append_string(&st->buffer,dhpub);
free(dhpub);
- hash=safe_malloc(st->hash->len, "generate_msg");
- hst=st->hash->init();
- st->hash->update(hst,st->buffer.start,st->buffer.size);
- st->hash->final(hst,hash);
- sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
- buf_append_string(&st->buffer,sig);
- free(sig);
- free(hash);
+
+ bool_t ok=privkey->sign(privkey->st,
+ st->buffer.start,
+ st->buffer.size,
+ &st->buffer);
+ if (!ok) goto fail;
return True;
+
+ fail:
+ return False;
}
static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
static bool_t unpick_msg(struct site *st, uint32_t type,
struct buffer_if *msg, struct msg *m)
{
+ unsigned minor;
+
+ m->n_pubkeys_accepted_nom=-1;
m->capab_transformnum=-1;
+ m->signing_key_index=-1;
m->hashstart=msg->start;
CHECK_AVAIL(msg,4);
m->dest=buf_unprepend_uint32(msg);
CHECK_AVAIL(&m->remote.extrainfo,2);
m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
}
+ if (type_is_msg23(type) && m->remote.extrainfo.size) {
+ m->n_pubkeys_accepted_nom = buf_unprepend_uint8(&m->remote.extrainfo);
+ if (!m->n_pubkeys_accepted_nom) return False;
+ for (int ki_nom=0; ki_nom<m->n_pubkeys_accepted_nom; ki_nom++) {
+ CHECK_AVAIL(&m->remote.extrainfo,KEYIDSZ);
+ struct sigkeyid *kid = buf_unprepend(&m->remote.extrainfo,KEYIDSZ);
+ if (ki_nom<MAX_SIG_KEYS) m->pubkeys_accepted[ki_nom] = kid;
+ }
+ } else {
+ m->n_pubkeys_accepted_nom = 1;
+ m->pubkeys_accepted[0] = &keyid_zero;
+ }
+ if (type_is_msg34(type) && m->remote.extrainfo.size) {
+ m->signing_key_index=buf_unprepend_uint8(&m->remote.extrainfo);
+ } else {
+ m->signing_key_index=0;
+ }
if (!unpick_name(msg,&m->local)) return False;
if (type==LABEL_PROD) {
CHECK_EMPTY(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;
- }
+ if (MSGMAJOR(type) == 3) do {
+ minor = MSGMINOR(type);
+#define MAYBE_READ_CAP(minminor, kind, dflt) do { \
+ if (minor < (minminor)) \
+ m->capab_##kind##num = (dflt); \
+ else { \
+ CHECK_AVAIL(msg, 1); \
+ m->capab_##kind##num = buf_unprepend_uint8(msg); \
+ } \
+} while (0)
+ MAYBE_READ_CAP(1, transform, CAPAB_BIT_ANCIENTTRANSFORM);
+#undef MAYBE_READ_CAP
+ } while (0);
CHECK_AVAIL(msg,2);
m->pklen=buf_unprepend_uint16(msg);
CHECK_AVAIL(msg,m->pklen);
m->pk=buf_unprepend(msg,m->pklen);
m->hashlen=msg->start-m->hashstart;
- CHECK_AVAIL(msg,2);
- m->siglen=buf_unprepend_uint16(msg);
- CHECK_AVAIL(msg,m->siglen);
- m->sig=buf_unprepend(msg,m->siglen);
- CHECK_EMPTY(msg);
- /* In `process_msg3_msg4' below, we assume that we can write a nul
- * terminator following the signature. Make sure there's enough space.
- */
- if (msg->start >= msg->base + msg->alloclen)
+ if (m->signing_key_index < 0 ||
+ m->signing_key_index >= st->peerkeys_kex->nkeys) {
+ return False;
+ }
+ struct sigpubkey_if *pubkey=
+ st->peerkeys_kex->keys[m->signing_key_index].pubkey;
+ if (!pubkey->unpick(pubkey->st,msg,&m->sig)) {
return False;
+ }
+
+ CHECK_EMPTY(msg);
return True;
}
return False;
}
if (type==LABEL_MSG2) return True;
- if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
+ if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)) {
*error="wrong remotely-generated nonce";
return False;
}
/* MSG3 has complicated rules about capabilities, which are
* handled in process_msg3. */
- if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
+ if (MSGMAJOR(type) == 3) return True;
if (m->remote_capabilities!=st->remote_capabilities) {
*error="remote capabilities changed";
return False;
return False;
}
-static bool_t generate_msg1(struct site *st)
+static bool_t kex_init(struct site *st)
{
+ keyset_dispose(&st->peerkeys_kex);
+ if (!st->peerkeys_current) {
+ slog(st,LOG_SETUP_INIT,"no peer public keys, abandoning key setup");
+ return False;
+ }
+ st->peerkeys_kex = keyset_dup(st->peerkeys_current);
st->random->generate(st->random->st,NONCELEN,st->localN);
- return generate_msg(st,LABEL_MSG1,"site:MSG1");
+ return True;
+}
+
+static bool_t generate_msg1(struct site *st, const struct msg *prompt_maybe_0)
+{
+ return
+ generate_msg(st,LABEL_MSG1,"site:MSG1",prompt_maybe_0);
}
static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
- const struct comm_addr *src, struct msg *m)
+ const struct comm_addr *src,
+ const 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
return True;
}
-static bool_t generate_msg2(struct site *st)
+static bool_t generate_msg2(struct site *st,
+ const struct msg *prompt_may_be_null)
{
- st->random->generate(st->random->st,NONCELEN,st->localN);
- return generate_msg(st,LABEL_MSG2,"site:MSG2");
+ return
+ generate_msg(st,LABEL_MSG2,"site:MSG2",prompt_may_be_null);
}
static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
- const struct comm_addr *src)
+ const struct comm_addr *src,
+ struct msg *m /* returned */)
{
- struct msg m;
cstring_t err;
- if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
- if (!check_msg(st,LABEL_MSG2,&m,&err)) {
+ if (!unpick_msg(st,LABEL_MSG2,msg2,m)) return False;
+ if (!check_msg(st,LABEL_MSG2,m,&err)) {
slog(st,LOG_SEC,"msg2: %s",err);
return False;
}
- st->setup_session_id=m.source;
- st->remote_capabilities=m.remote_capabilities;
+ 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)
+ uint32_t remote_crypto_caps = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
+ if (!remote_crypto_caps)
/* old secnets only had this one transform */
- remote_transforms = 1UL << CAPAB_TRANSFORMNUM_ANCIENT;
+ remote_crypto_caps = 1UL << CAPAB_BIT_ANCIENTTRANSFORM;
+
+#define CHOOSE_CRYPTO(kind, whats) do { \
+ struct kind##_if *iface; \
+ uint32_t bit, ours = 0; \
+ int i; \
+ for (i= 0; i < st->n##kind##s; i++) { \
+ iface=st->kind##s[i]; \
+ bit = 1UL << iface->capab_bit; \
+ if (bit & remote_crypto_caps) goto kind##_found; \
+ ours |= bit; \
+ } \
+ slog(st,LOG_ERROR,"no " whats " in common" \
+ " (us %#"PRIx32"; them: %#"PRIx32")", \
+ st->local_capabilities & ours, remote_crypto_caps); \
+ return False; \
+kind##_found: \
+ st->chosen_##kind = iface; \
+} while (0)
- 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;
+ CHOOSE_CRYPTO(transform, "transforms");
+
+#undef CHOOSE_CRYPTO
- memcpy(st->remoteN,m.nR,NONCELEN);
+ memcpy(st->remoteN,m->nR,NONCELEN);
return True;
}
-static bool_t generate_msg3(struct site *st)
+static bool_t generate_msg3(struct site *st, const struct msg *prompt)
{
/* 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,
- (st->remote_capabilities & CAPAB_TRANSFORM_MASK
- ? LABEL_MSG3BIS : LABEL_MSG3),
- "site:MSG3");
+ (st->remote_capabilities & CAPAB_TRANSFORM_MASK)
+ ? LABEL_MSG3BIS
+ : LABEL_MSG3,
+ "site:MSG3",prompt);
}
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' - already checked that this will fit */
- m->sig[m->siglen]=0;
- if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
+ int ki;
+
+ if (m->signing_key_index >= 0) {
+ if (m->signing_key_index >= st->peerkeys_kex->nkeys)
+ return False;
+ ki=m->signing_key_index;
+ } else {
+ for (ki=0; ki<st->peerkeys_kex->nkeys; ki++)
+ if (sigkeyid_equal(&keyid_zero,&st->peerkeys_kex->keys[ki].id))
+ goto found;
+ /* not found */
+ slog(st,LOG_ERROR,
+ "peer signed with keyid zero, which we do not accept");
+ return False;
+ found:;
+ }
+ struct sigpubkey_if *pubkey=st->peerkeys_kex->keys[ki].pubkey;
+
+ if (!pubkey->check(pubkey->st,
+ m->hashstart,m->hashlen,
+ &m->sig)) {
slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
- free(hash);
return False;
}
- free(hash);
st->remote_adv_mtu=m->remote_mtu;
}
static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
- const struct comm_addr *src, uint32_t msgtype)
+ const struct comm_addr *src, uint32_t msgtype,
+ struct msg *m /* returned */)
{
- struct msg m;
cstring_t err;
- assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
+ switch (msgtype) {
+ case CASES_MSG3_KNOWN: break;
+ default: assert(0);
+ }
- if (!unpick_msg(st,msgtype,msg3,&m)) return False;
- if (!check_msg(st,msgtype,&m,&err)) {
+ 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;
+ uint32_t capab_adv_late = m->remote_capabilities
+ & ~st->remote_capabilities & st->early_capabilities;
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);
+ 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;
+#define CHOSE_CRYPTO(kind, what) do { \
+ struct kind##_if *iface; \
+ int i; \
+ for (i=0; i<st->n##kind##s; i++) { \
+ iface=st->kind##s[i]; \
+ if (iface->capab_bit == m->capab_##kind##num) \
+ goto kind##_found; \
+ } \
+ slog(st,LOG_SEC,"peer chose unknown-to-us " what " %d!", \
+ m->capab_##kind##num); \
+ return False; \
+kind##_found: \
+ st->chosen_##kind=iface; \
+} while (0)
+
+ CHOSE_CRYPTO(transform, "transform");
+
+#undef CHOSE_CRYPTO
- if (!process_msg3_msg4(st,&m))
+ if (!process_msg3_msg4(st,m))
return False;
+ /* Update our idea of the remote site's capabilities, now that we've
+ * verified that its message was authentic.
+ *
+ * Our previous idea of the remote site's capabilities came from the
+ * unauthenticated MSG1. We've already checked that this new message
+ * doesn't change any of the bits we relied upon in the past, but it may
+ * also have set additional capability bits. We simply throw those away
+ * now, and use the authentic capabilities from this MSG3. */
+ st->remote_capabilities=m->remote_capabilities;
+
/* Terminate their DH public key with a '0' */
- m.pk[m.pklen]=0;
+ m->pk[m->pklen]=0;
/* Invent our DH secret key */
st->random->generate(st->random->st,st->dh->len,st->dhsecret);
/* Generate the shared key and set up the transform */
- if (!set_new_transform(st,m.pk)) return False;
+ if (!set_new_transform(st,m->pk)) return False;
return True;
}
-static bool_t generate_msg4(struct site *st)
+static bool_t generate_msg4(struct site *st, const struct msg *prompt)
{
/* We have both nonces, their public key and our private key. Generate
our public key, sign it and send it to them. */
- return generate_msg(st,LABEL_MSG4,"site:MSG4");
+ return generate_msg(st,LABEL_MSG4,"site:MSG4",prompt);
}
static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
- const struct comm_addr *src)
+ const struct comm_addr *src,
+ struct msg *m /* returned */)
{
- struct msg m;
cstring_t err;
- if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
- if (!check_msg(st,LABEL_MSG4,&m,&err)) {
+ if (!unpick_msg(st,LABEL_MSG4,msg4,m)) return False;
+ if (!check_msg(st,LABEL_MSG4,m,&err)) {
slog(st,LOG_SEC,"msg4: %s",err);
return False;
}
- if (!process_msg3_msg4(st,&m))
+ if (!process_msg3_msg4(st,m))
return False;
/* Terminate their DH public key with a '0' */
- m.pk[m.pklen]=0;
+ m->pk[m->pklen]=0;
/* Generate the shared key and set up the transform */
- if (!set_new_transform(st,m.pk)) return False;
+ if (!set_new_transform(st,m->pk)) return False;
return True;
}
/* Leaves transformed part of buffer untouched */
}
-static bool_t generate_msg5(struct site *st)
+static bool_t generate_msg5(struct site *st, const struct msg *prompt)
{
cstring_t transform_err;
/* Give the netlink code an opportunity to put its own stuff in the
message (configuration information, etc.) */
buf_prepend_uint32(&st->buffer,LABEL_MSG6);
- int problem = call_transform_forwards(st,transform,
- &st->buffer,&transform_err);
+ transform_apply_return 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,session_id);
}
-static bool_t generate_msg6(struct site *st)
+static bool_t generate_msg6(struct site *st, const struct msg *prompt)
{
if (!is_transform_valid(st->new_transform))
return False;
return True;
}
-static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
+static transform_apply_return
+decrypt_msg0(struct site *st, struct buffer_if *msg0,
const struct comm_addr *src)
{
cstring_t transform_err, auxkey_err, newkey_err="n/a";
struct msg0 m;
- uint32_t problem;
+ transform_apply_return problem;
if (!unpick_msg0(st,msg0,&m)) return False;
if (!st->auxiliary_is_new)
delete_one_key(st,&st->auxiliary_key,
"peer has used new key","auxiliary key",LOG_SEC);
- return True;
+ return 0;
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
buffer_copy(msg0, &st->scratch);
problem = call_transform_reverse(st,st->auxiliary_key.transform,
msg0,&auxkey_err);
- if (problem==0) {
+ if (!problem) {
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
st->auxiliary_is_new=0;
st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
}
- return True;
+ return 0;
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
if (st->state==SITE_SENTMSG5) {
buffer_copy(msg0, &st->scratch);
BUF_FREE(&st->buffer);
st->timeout=0;
activate_new_key(st);
- return True; /* do process the data in this packet */
+ return 0; /* do process the data in this packet */
}
- if (problem==2)
- goto skew;
+ if (transform_apply_return_badseq(problem))
+ goto badseq;
}
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",0);
send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
- return False;
+ assert(problem);
+ return problem;
- skew:
- slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
+ badseq:
+ slog(st,LOG_DROP,"transform: %s (bad seq.)",transform_err);
assert(problem);
return problem;
}
const struct comm_addr *src)
{
uint32_t type;
-
- if (!decrypt_msg0(st,msg0,src))
+ transform_apply_return problem;
+
+ problem = decrypt_msg0(st,msg0,src);
+ if (problem==transform_apply_seqdupe) {
+ /* We recently received another copy of this packet, maybe due
+ * to polypath. That's not a problem; indeed, for the
+ * purposes of transport address management it is a success.
+ * But we don't want to process the packet. */
+ transport_data_msgok(st,src);
+ return False;
+ }
+ if (problem)
return False;
CHECK_AVAIL(msg0,4);
switch (st->state) {
case SITE_RESOLVE:
if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
- enter_new_state(st,SITE_SENTMSG1);
+ enter_new_state(st,SITE_SENTMSG1,0);
} else {
/* Can't figure out who to try to to talk to */
slog(st,LOG_SETUP_INIT,
} 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;
+ st->key_renegotiate_time=st->now+wait_timeout(st);
} else {
slog(st,LOG_SETUP_INIT,"resolution failed: "
" continuing to use source address of peer's packets");
slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
return enter_state_resolve(st);
} else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
- return enter_new_state(st,SITE_SENTMSG1);
+ return enter_new_state(st,SITE_SENTMSG1,0);
}
slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
return False;
static void enter_state_run(struct site *st)
{
- slog(st,LOG_STATE,"entering state RUN");
+ slog(st,LOG_STATE,"entering state RUN%s",
+ current_valid(st) ? " (keyed)" : " (unkeyed)");
st->state=SITE_RUN;
st->timeout=0;
st->setup_session_id=0;
transport_peers_clear(st,&st->setup_peers);
+ keyset_dispose(&st->peerkeys_kex);
FILLZERO(st->localN);
FILLZERO(st->remoteN);
dispose_transform(&st->new_transform);
return ensure_resolving(st);
}
-static bool_t enter_new_state(struct site *st, uint32_t next)
+static bool_t enter_new_state(struct site *st, uint32_t next,
+ const struct msg *prompt
+ /* may be 0 for SENTMSG1 */)
{
- bool_t (*gen)(struct site *st);
+ bool_t (*gen)(struct site *st, const struct msg *prompt);
int r;
slog(st,LOG_STATE,"entering state %s",state_name(next));
switch(next) {
case SITE_SENTMSG1:
state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
+ if (!kex_init(st)) return False;
gen=generate_msg1;
st->msg1_crossed_logged = False;
break;
case SITE_SENTMSG2:
state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
+ if (!kex_init(st)) return False;
gen=generate_msg2;
break;
case SITE_SENTMSG3:
if (hacky_par_start_failnow()) return False;
- r= gen(st) && send_msg(st);
+ r= gen(st,prompt) && send_msg(st);
hacky_par_end(&r,
st->setup_retries, st->setup_retry_interval,
static void enter_state_wait(struct site *st)
{
slog(st,LOG_STATE,"entering state WAIT");
- st->timeout=st->now+st->wait_timeout;
+ st->timeout=st->now+wait_timeout(st);
st->state=SITE_WAIT;
set_link_quality(st);
BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
}
static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
- uint32_t type, struct msg *m)
+ uint32_t type, struct msg *m,
+ struct priomsg *whynot)
/* 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);
+
+ if (!unpick_msg(st,type,buf,m)) {
+ priomsg_update_fixed(whynot, comm_notify_whynot_unpick, "malformed");
+ return False;
+ }
+#define NAME_MATCHES(lr) \
+ if (!name_matches(&m->lr, st->lr##name)) { \
+ if (priomsg_update_fixed(whynot, comm_notify_whynot_name_##lr, \
+ "unknown " #lr " name: ")) { \
+ truncmsg_add_packet_string(&whynot->m, m->lr.len, m->lr.name); \
+ } \
+ return False; \
+ }
+ NAME_MATCHES(remote);
+ NAME_MATCHES(local );
+#undef NAME_MATCHES
+
+ return True;
+}
+
+static bool_t we_have_priority(struct site *st, const struct msg *m) {
+ if (st->local_capabilities & m->remote_capabilities &
+ CAPAB_PRIORITY_MOBILE) {
+ if (st->local_mobile) return True;
+ if (st-> peer_mobile) return False;
+ }
+ return st->our_name_later;
+}
+
+static bool_t setup_late_msg_ok(struct site *st,
+ const struct buffer_if *buf_in,
+ uint32_t msgtype,
+ const struct comm_addr *source,
+ struct msg *m /* returned */) {
+ /* For setup packets which seem from their type like they are
+ * late. Maybe they came via a different path. All we do is make
+ * a note of the sending address, iff they look like they are part
+ * of the current key setup attempt. */
+ if (!named_for_us(st,buf_in,msgtype,m,0))
+ /* named_for_us calls unpick_msg which gets the nonces */
+ return False;
+ if (!consttime_memeq(m->nR,st->remoteN,NONCELEN) ||
+ !consttime_memeq(m->nL,st->localN, NONCELEN))
+ /* spoof ? from stale run ? who knows */
+ return False;
+ transport_setup_msgok(st,source);
+ return True;
}
/* This function is called by the communication device to deliver
this current site instance (and should therefore not be processed
by other sites), even if the packet was otherwise ignored. */
static bool_t site_incoming(void *sst, struct buffer_if *buf,
- const struct comm_addr *source)
+ const struct comm_addr *source,
+ struct priomsg *whynot)
{
struct site *st=sst;
uint32_t dest=get_uint32(buf->start);
uint32_t msgtype=get_uint32(buf->start+8);
- struct msg named_msg;
+ struct msg msg;
+ /* initialised by named_for_us, or process_msgN for N!=1 */
if (msgtype==LABEL_MSG1) {
- if (!named_for_us(st,buf,msgtype,&named_msg))
+ if (!named_for_us(st,buf,msgtype,&msg,whynot))
return False;
/* It's a MSG1 addressed to us. Decide what to do about it. */
dump_packet(st,buf,source,True,True);
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)) {
+ if (process_msg1(st,buf,source,&msg)) {
slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
- bool_t entered=enter_new_state(st,SITE_SENTMSG2);
+ bool_t entered=enter_new_state(st,SITE_SENTMSG2,&msg);
if (entered && st->addresses && st->local_mobile)
/* We must do this as the very last thing, because
the resolver callback might reenter us. */
/* 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) {
+ if (we_have_priority(st,&msg)) {
BUF_FREE(buf);
if (!st->msg1_crossed_logged++)
- slog(st,LOG_DUMP,"crossed msg1s; we are higher "
+ slog(st,LOG_SETUP_INIT,"crossed msg1s; we are higher "
"priority => ignore incoming msg1");
return True;
} else {
- slog(st,LOG_DUMP,"crossed msg1s; we are lower "
+ slog(st,LOG_SETUP_INIT,"crossed msg1s; we are lower "
"priority => use incoming msg1");
- if (process_msg1(st,buf,source,&named_msg)) {
+ if (process_msg1(st,buf,source,&msg)) {
BUF_FREE(&st->buffer); /* Free our old message 1 */
transport_setup_msgok(st,source);
- enter_new_state(st,SITE_SENTMSG2);
+ enter_new_state(st,SITE_SENTMSG2,&msg);
} else {
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_SENTMSG2 ||
+ st->state==SITE_SENTMSG4) {
+ if (consttime_memeq(msg.nR,st->remoteN,NONCELEN)) {
+ /* We are ahead in the protocol, but that msg1 had the
+ * peer's nonce so presumably it is from this key
+ * exchange run, via a slower route */
+ transport_setup_msgok(st,source);
+ } else {
+ slog(st,LOG_UNEXPECTED,"competing incoming message 1");
+ }
+ BUF_FREE(buf);
+ return True;
}
/* The message 1 was received at an unexpected stage of the
- key setup. XXX POLICY - what do we do? */
+ key setup. Well, they lost the race. */
slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
BUF_FREE(buf);
return True;
}
if (msgtype==LABEL_PROD) {
- if (!named_for_us(st,buf,msgtype,&named_msg))
+ if (!named_for_us(st,buf,msgtype,&msg,whynot))
return False;
dump_packet(st,buf,source,True,True);
if (st->state!=SITE_RUN) {
case LABEL_MSG2:
/* Setup packet: expected only in state SENTMSG1 */
if (st->state!=SITE_SENTMSG1) {
+ if ((st->state==SITE_SENTMSG3 ||
+ st->state==SITE_SENTMSG5) &&
+ setup_late_msg_ok(st,buf,msgtype,source,&msg))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG2");
- } else if (process_msg2(st,buf,source)) {
+ } else if (process_msg2(st,buf,source,&msg)) {
transport_setup_msgok(st,source);
- enter_new_state(st,SITE_SENTMSG3);
+ enter_new_state(st,SITE_SENTMSG3,&msg);
} else {
slog(st,LOG_SEC,"invalid MSG2");
}
break;
- case LABEL_MSG3:
- case LABEL_MSG3BIS:
+ case CASES_MSG3_KNOWN:
/* Setup packet: expected only in state SENTMSG2 */
if (st->state!=SITE_SENTMSG2) {
+ if ((st->state==SITE_SENTMSG4) &&
+ setup_late_msg_ok(st,buf,msgtype,source,&msg))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG3");
- } else if (process_msg3(st,buf,source,msgtype)) {
+ } else if (process_msg3(st,buf,source,msgtype,&msg)) {
transport_setup_msgok(st,source);
- enter_new_state(st,SITE_SENTMSG4);
+ enter_new_state(st,SITE_SENTMSG4,&msg);
} else {
slog(st,LOG_SEC,"invalid MSG3");
}
case LABEL_MSG4:
/* Setup packet: expected only in state SENTMSG3 */
if (st->state!=SITE_SENTMSG3) {
+ if ((st->state==SITE_SENTMSG5) &&
+ setup_late_msg_ok(st,buf,msgtype,source,&msg))
+ break;
slog(st,LOG_UNEXPECTED,"unexpected MSG4");
- } else if (process_msg4(st,buf,source)) {
+ } else if (process_msg4(st,buf,source,&msg)) {
transport_setup_msgok(st,source);
- enter_new_state(st,SITE_SENTMSG5);
+ enter_new_state(st,SITE_SENTMSG5,&msg);
} else {
slog(st,LOG_SEC,"invalid MSG4");
}
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);
+ enter_new_state(st,SITE_RUN,&msg);
} else {
slog(st,LOG_SEC,"invalid MSG5");
}
return True;
}
+ priomsg_update_fixed(whynot, comm_notify_whynot_general,
+ "not MSG1 or PROD; unknown dest index");
return False;
}
crypto operations, but that's a task for another day. */
}
+static void setup_sethash(struct site *st, dict_t *dict,
+ struct hash_if **hash, struct cloc loc,
+ sig_sethash_fn *sethash, void *sigkey_st) {
+ if (!*hash) *hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
+ sethash(sigkey_st,*hash);
+}
+#define SETUP_SETHASH(k) do{ \
+ if ((k)->sethash) \
+ setup_sethash(st,dict, &hash,loc, (k)->sethash,(k)->st); \
+}while(0)
+
static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
list_t *args)
{
st->ops.st=st;
st->ops.control=site_control;
st->ops.status=site_status;
+ st->peerkeys_path=0;
+ st->peerkeys_current=st->peerkeys_kex=0;
/* First parameter must be a dict */
item=list_elem(args,0);
assert(index_sequence < 0xffffffffUL);
st->index = ++index_sequence;
st->local_capabilities = 0;
+ st->early_capabilities = CAPAB_PRIORITY_MOBILE;
st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
#define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
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->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
+ struct hash_if *hash=0;
+
+ st->privkeys=find_cl_if(dict,"key-cache",CL_PRIVCACHE,False,"site",loc);
+ if (!st->privkeys) {
+ st->privkey_fixed=
+ find_cl_if(dict,"local-key",CL_SIGPRIVKEY,True,"site",loc);
+ SETUP_SETHASH(st->privkey_fixed);
+ }
+
+ struct sigpubkey_if *fixed_pubkey
+ =find_cl_if(dict,"key",CL_SIGPUBKEY,False,"site",loc);
+ st->peerkeys_path=dict_read_string(dict,"peer-keys",fixed_pubkey==0,
+ "site",loc);
+ if (st->peerkeys_path) {
+ st->peerkeys_current=keyset_load(st->peerkeys_path,
+ &st->scratch,st->log,M_ERR);
+ if (fixed_pubkey) {
+ fixed_pubkey->dispose(fixed_pubkey->st);
+ }
+ } else {
+ assert(fixed_pubkey);
+ SETUP_SETHASH(fixed_pubkey);
+ NEW(st->peerkeys_current);
+ st->peerkeys_current->refcount=1;
+ st->peerkeys_current->nkeys=1;
+ st->peerkeys_current->keys[0].id=keyid_zero;
+ st->peerkeys_current->keys[0].pubkey=fixed_pubkey;
+ slog(st,LOG_SIGKEYS,
+ "using old-style fixed peer public key (no `peer-keys')");
+ }
+
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);
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);
#define DEFAULT(D) (st->peer_mobile || st->local_mobile \
? DEFAULT_MOBILE_##D : DEFAULT_##D)
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->wait_timeout_mean= 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(
/* 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->setup_priority=(strcmp(st->localname,st->remotename)>0);
+ st->our_name_later=(strcmp(st->localname,st->remotename)>0);
buffer_new(&st->buffer,SETUP_BUFFER_LEN);
st->sharedsecretlen=st->sharedsecretallocd=0;
st->sharedsecret=0;
- 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;
- }
+#define SET_CAPBIT(bit) do { \
+ uint32_t capflag = 1UL << (bit); \
+ if (st->local_capabilities & capflag) \
+ slog(st,LOG_ERROR,"capability bit" \
+ " %d (%#"PRIx32") reused", (bit), capflag); \
+ st->local_capabilities |= capflag; \
+} while (0)
+
+ for (i=0; i<st->ntransforms; i++)
+ SET_CAPBIT(st->transforms[i]->capab_bit);
+
+#undef SET_CAPBIT
+
+ if (st->local_mobile || st->peer_mobile)
+ st->local_capabilities |= CAPAB_PRIORITY_MOBILE;
/* We need to register the remote networks with the netlink device */
uint32_t netlink_mtu; /* local virtual interface mtu */
~ianmdlvl / secnet.git / blobdiff