int ncomms;
struct resolver_if *resolver;
struct log_if *log;
+ struct hash_if *defhash;
struct random_if *random;
struct privcache_if *privkeys;
struct sigprivkey_if *privkey_fixed;
return False;
privkey_found:
+ slog(st,LOG_SIGKEYS,"using private key #%d " SIGKEYID_PR_FMT,
+ ki, SIGKEYID_PR_VAL(prompt->pubkeys_accepted[ki]));
buf_append_uint8(&st->buffer,ki);
}
int logcl_enoent)
{
struct peer_keyset *atsuffix=
- keyset_load(file,&st->scratch,st->log,logcl_enoent);
+ keyset_load(file,&st->scratch,st->log,logcl_enoent,st->defhash);
if (!atsuffix) return;
if (st->peerkeys_current &&
static void peerkeys_check_for_update(struct site *st)
{
- /* peerkeys files
- *
- * <F> live file, loaded on startup, updated by secnet
- * (only). * in-memory peerkeys_current is kept
- * synced with this file
- *
- * <F>~update update file from config manager, checked before
- * every key exchange. config manager must rename
- * this file into place; it will be renamed and
- * then removed by secnet.
- *
- * <F>~proc update file being processed by secnet.
- * only secnet may write or remove.
- *
- * <F>~incoming update file from peer, being received by secnet
- * may be incomplete, unverified, or even malicious
- * only secnet may write or remove.
- *
- * secnet discards updates that are not more recent than (by
- * serial) the live file. But it may not process updates
- * immediately.
- *
- * The implied keyset to be used is MAX(live, proc, update).
- *
- * secnet does:
- * check live vs proc, either mv proc live or rm proc
- * if proc doesn't exist, mv update proc
- *
- * make-secnet-sites does:
- * write: rename something onto update
- * read: read update,proc,live in that order and take max
- *
- * We support only one concurrent secnet, one concurrent
- * writing make-secnet-sites, and any number of readers.
- * We want to maintain a live file at all times as that
- * is what secnet actually reads at startup and uses.
- *
- * Proof that this is sound:
- * Let us regard update,proc,live as i=0,1,2
- * Files contain public key sets and are manipulated as
- * a whole, and we may regard key sets with the same
- * serial as equivalent.
- * We talk below about reading as if it were atomic.
- * Actually the atomic operation is open(2); the
- * reading gets whatever that name refers to. So
- * we can model this as an atomic read.
- * secnet eventually moves all data into the live file
- * or deletes it, so there should be no indefinitely
- * stale data; informally this means we can disregard
- * the possibility of very old serials and regard
- * serials as fully ordered. (We don't bother with
- * a formal proof of this property.)
- * Consequently we will only think about the serial
- * and not the contents. We treat absent files as
- * minimal (we will write -1 for convenience although
- * we don't mean a numerical value). We write S(i).
- *
- * Invariant 1 for secnet's transformations is as follows:
- * Each file S(i) is only reduced (to S'(i)) if for some j S'(j)
- * >= S(i), with S'(j) either being >= S(i) beforehand, or
- * updated atomically together with S(i).
- *
- * Proof of invariant 1 for the secnet operations:
- * (a) check live vs proc, proc>live, mv:
- * j=2, i=1; S'(i)=-1, so S(i) is being reduced. S'(j) is
- * equal to S(i), and the rename is atomic [1], so S'(j) and
- * S'(i) are updated simultaneously. S(j) is being
- * increased. (There are no hazards from concurrent writers;
- * only we ourselves (secnet) write to live or proc.)
- * (b) check live vs proc, proc<=live, rm:
- * j=2, i=1; S'(i)=-1, so S(i) is being reduced. But
- * S(j) is >= $(i) throughout. (Again, no concurrent
- * writer hazards.)
- * (c) mv update proc (when proc does not exist):
- * j=1, i=0; S(i) is being reduced to -1. But simultaneously
- * S(j) is being increased to the old S(i). Our precondition
- * (proc not existing) is not subject to a concurrent writer
- * hazards because only we write to proc; our action is
- * atomic and takes whatever update is available (if any).
- *
- * Proof of soundness for the mss reading operation:
- * Let M be MAX(\forall S) at the point where mss reads update.
- * Invariant 2: when mss reads S(k), MAX(K, S(k)..S(2)) >= M,
- * where K is the max S it has seen so far. Clearly this is
- * true for k=0 (with K==-1). secnet's operations never break
- * this invariant because if any S() is reduced, another one
- * counted must be increased. mss's step operation
- * updates K with S(k), so MAX(K', S(k+1)..)=MAX(K, S(k)..),
- * and updates k to k+1, preserving the invariant.
- * At the end we have k=3 and K=>M. Since secnet never
- * invents serials, K=M in the absence of an mss update
- * with a bigger S.
- *
- * Consideration of the mss update operation:
- * Successive serials from sites file updates etc. are supposed
- * to be increasing. When this is true, M is increased. A
- * concurrent reading mss which makes its first read after the
- * update will get the new data (by the proofs above). This
- * seems to be the required property.
- *
- * QED.
- *
- * [1] From "Base Specifications issue 7",
- * 2.9.7 Thread Interactions with Regular File Operations
- * All of the following functions shall be atomic with respect to
- * each other in the effects specified in POSIX.1-2017 when they
- * operate on regular files or symbolic links:
- * ... rename ... open ...
- */
if (!st->peerkeys_path) return;
pathprefix_template_setsuffix(&st->peerkeys_tmpl,"~proc");
int r=rename(inputp,oursp);
if (r) {
- slog(st,LOG_ERROR,"failed to claim key update file %s as %s: %s\n",
+ slog(st,LOG_ERROR,"failed to claim key update file %s as %s: %s",
inputp,oursp,strerror(errno));
return;
}
if (!pubkey->check(pubkey->st,
m->hashstart,m->hashlen,
&m->sig)) {
- slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
+ slog(st,LOG_SEC,"msg3/msg4 signature failed check!"
+ " (key #%d " SIGKEYID_PR_FMT ")",
+ ki, SIGKEYID_PR_VAL(&st->peerkeys_kex->keys[ki].id));
return False;
}
+ slog(st,LOG_SIGKEYS,"verified peer signature with key #%d "
+ SIGKEYID_PR_FMT, ki,
+ SIGKEYID_PR_VAL(&st->peerkeys_kex->keys[ki].id));
st->remote_adv_mtu=m->remote_mtu;
}
static void setup_sethash(struct site *st, dict_t *dict,
- struct hash_if **hash, struct cloc loc,
+ 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);
+ if (!st->defhash)
+ cfgfatal(loc,"site","other settings imply `hash' key is needed");
+ sethash(sigkey_st,st->defhash);
}
#define SETUP_SETHASH(k) do{ \
if ((k)->sethash) \
- setup_sethash(st,dict, &hash,loc, (k)->sethash,(k)->st); \
+ setup_sethash(st,dict,loc, (k)->sethash,(k)->st); \
}while(0)
static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
- struct hash_if *hash=0;
+ st->defhash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
st->privkeys=find_cl_if(dict,"key-cache",CL_PRIVCACHE,False,"site",loc);
if (!st->privkeys) {
pathprefix_template_init(&st->peerkeys_tmpl,st->peerkeys_path,
PEERKEYS_SUFFIX_MAXLEN + 1 /* nul */);
st->peerkeys_current=keyset_load(st->peerkeys_path,
- &st->scratch,st->log,M_ERR);
+ &st->scratch,st->log,M_ERR,
+ st->defhash);
if (fixed_pubkey) {
fixed_pubkey->dispose(fixed_pubkey->st);
}