X-Git-Url: https://git.distorted.org.uk/~mdw/tripe/blobdiff_plain/35c8b547dde529693875087d67fa60bf88319d2b..e713954af6c6dd7c05877b9002247c4cbd336b31:/server/keyexch.c?ds=inline
diff --git a/server/keyexch.c b/server/keyexch.c
index 1527a297..9d08bec6 100644
--- a/server/keyexch.c
+++ b/server/keyexch.c
@@ -9,19 +9,18 @@
*
* This file is part of Trivial IP Encryption (TrIPE).
*
- * TrIPE is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * TrIPE is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your
+ * option) any later version.
*
- * TrIPE is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * TrIPE is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
*
* You should have received a copy of the GNU General Public License
- * along with TrIPE; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with TrIPE. If not, see .
*/
/*----- Header files ------------------------------------------------------*/
@@ -75,13 +74,6 @@
* Switch received. Committed; send data; move to @KXS_SWITCH@.
*/
-/*----- Tunable parameters ------------------------------------------------*/
-
-#define T_VALID SEC(20) /* Challenge validity period */
-#define T_RETRY SEC(10) /* Challenge retransmit interval */
-
-#define VALIDP(kx, now) ((now) < (kx)->t_valid)
-
/*----- Static tables -----------------------------------------------------*/
static const char *const pkname[] = {
@@ -90,11 +82,22 @@ static const char *const pkname[] = {
/*----- Various utilities -------------------------------------------------*/
+/* --- @VALIDP@ --- *
+ *
+ * Arguments: @const keyexch *kx@ = key exchange state
+ * @time_t now@ = current time in seconds
+ *
+ * Returns: Whether the challenge in the key-exchange state is still
+ * valid or should be regenerated.
+ */
+
+#define VALIDP(kx, now) ((now) < (kx)->t_valid)
+
/* --- @hashge@ --- *
*
* Arguments: @ghash *h@ = pointer to hash context
- * @group *g@ = pointer to group
- * @ge *x@ = pointer to group element
+ * @const dhgrp *g@ = pointer to group
+ * @const dhge *Y@ = pointer to group element
*
* Returns: ---
*
@@ -102,12 +105,12 @@ static const char *const pkname[] = {
* @buf_t@.
*/
-static void hashge(ghash *h, group *g, ge *x)
+static void hashge(ghash *h, const dhgrp *g, const dhge *Y)
{
buf b;
buf_init(&b, buf_t, sizeof(buf_t));
- G_TOBUF(g, &b, x);
+ g->ops->stge(g, &b, Y, DHFMT_HASH);
assert(BOK(&b));
GH_HASH(h, BBASE(&b), BLEN(&b));
}
@@ -115,59 +118,60 @@ static void hashge(ghash *h, group *g, ge *x)
/* --- @mpmask@ --- *
*
* Arguments: @buf *b@ = output buffer
- * @mp *x@ = the plaintext integer
+ * @const dhgrp *g@ = the group
+ * @const dhsc *x@ = the plaintext scalar
* @size_t n@ = the expected size of the plaintext
* @gcipher *mgfc@ = mask-generating function to use
* @const octet *k@ = pointer to key material
* @size_t ksz@ = size of the key
*
- * Returns: Pointer to the output.
+ * Returns: ---
*
- * Use: Masks a multiprecision integer: returns %$x \xor H(k)$%, so
- * it's a random oracle thing rather than an encryption thing.
+ * Use: Masks a scalar: returns %$x \xor H(k)$%, so it's a random
+ * oracle thing rather than an encryption thing. Breaks the
+ * output buffer on error.
*/
-static octet *mpmask(buf *b, mp *x, size_t n,
- const gccipher *mgfc, const octet *k, size_t ksz)
+static void mpmask(buf *b, const dhgrp *g, const dhsc *x, size_t n,
+ const gccipher *mgfc, const octet *k, size_t ksz)
{
gcipher *mgf;
octet *p;
- if ((p = buf_get(b, n)) == 0)
- return (0);
+ if ((p = buf_get(b, n)) == 0) return;
mgf = GC_INIT(mgfc, k, ksz);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: masking index = %s", mpstr(x));
+ trace(T_CRYPTO, "crypto: masking scalar = %s", g->ops->scstr(g, x));
trace_block(T_CRYPTO, "crypto: masking key", k, ksz);
}))
- mp_storeb(x, buf_t, n);
+ if (g->ops->stsc(g, buf_t, n, x)) { buf_break(b); return; }
GC_ENCRYPT(mgf, buf_t, p, n);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace_block(T_CRYPTO, "crypto: index plaintext", buf_t, n);
+ trace_block(T_CRYPTO, "crypto: scalar plaintext", buf_t, n);
trace_block(T_CRYPTO, "crypto: masked ciphertext", p, n);
}))
GC_DESTROY(mgf);
- return (p);
}
/* --- @mpunmask@ --- *
*
- * Arguments: @mp *d@ = the output integer
+ * Arguments: @const dhgrp *g@ = the group
* @const octet *p@ = pointer to the ciphertext
* @size_t n@ = the size of the ciphertext
* @gcipher *mgfc@ = mask-generating function to use
* @const octet *k@ = pointer to key material
* @size_t ksz@ = size of the key
*
- * Returns: The decrypted integer, or null.
+ * Returns: The decrypted scalar, or null.
*
- * Use: Unmasks a multiprecision integer.
+ * Use: Unmasks a scalar.
*/
-static mp *mpunmask(mp *d, const octet *p, size_t n,
- const gccipher *mgfc, const octet *k, size_t ksz)
+static dhsc *mpunmask(const dhgrp *g, const octet *p, size_t n,
+ const gccipher *mgfc, const octet *k, size_t ksz)
{
gcipher *mgf;
+ dhsc *x;
mgf = GC_INIT(mgfc, k, ksz);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
@@ -175,22 +179,23 @@ static mp *mpunmask(mp *d, const octet *p, size_t n,
trace_block(T_CRYPTO, "crypto: masked ciphertext", p, n);
}))
GC_DECRYPT(mgf, p, buf_t, n);
- d = mp_loadb(d, buf_t, n);
+ x = g->ops->ldsc(g, buf_t, n);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace_block(T_CRYPTO, "crypto: index plaintext", buf_t, n);
- trace(T_CRYPTO, "crypto: unmasked index = %s", mpstr(d));
+ trace_block(T_CRYPTO, "crypto: scalar plaintext", buf_t, n);
+ trace(T_CRYPTO, "crypto: unmasked scalar = %s",
+ x ? g->ops->scstr(g, x) : "");
}))
GC_DESTROY(mgf);
- return (d);
+ return (x);
}
/* --- @hashcheck@ --- *
*
* Arguments: @keyexch *kx@ = pointer to key-exchange block
- * @ge *kpub@ = sender's public key
- * @ge *cc@ = receiver's challenge
- * @ge *c@ = sender's challenge
- * @ge *y@ = reply to sender's challenge
+ * @const dhge *K@ = sender's public key
+ * @const dhge *CC@ = receiver's challenge
+ * @const dhge *C@ = sender's challenge
+ * @const dhge *Y@ = reply to sender's challenge
*
* Returns: Pointer to the hash value (in @buf_t@)
*
@@ -198,29 +203,30 @@ static mp *mpunmask(mp *d, const octet *p, size_t n,
* indices to prove the validity of challenges. This computes
* the masking key used in challenge check values. This is
* really the heart of the whole thing, since it ensures that
- * the index can be recovered from the history of hashing
+ * the scalar can be recovered from the history of hashing
* queries, which gives us (a) a proof that the authentication
* process is zero-knowledge, and (b) a proof that the whole
* key-exchange is deniable.
*/
-static const octet *hashcheck(keyexch *kx, ge *kpub, ge *cc, ge *c, ge *y)
+static const octet *hashcheck(keyexch *kx, const dhge *K,
+ const dhge *CC, const dhge *C, const dhge *Y)
{
ghash *h = GH_INIT(kx->kpriv->algs.h);
- group *g = kx->kpriv->g;
+ const dhgrp *g = kx->kpriv->grp;
HASH_STRING(h, "tripe-expected-reply");
- hashge(h, g, kpub);
- hashge(h, g, cc);
- hashge(h, g, c);
- hashge(h, g, y);
+ hashge(h, g, K);
+ hashge(h, g, CC);
+ hashge(h, g, C);
+ hashge(h, g, Y);
GH_DONE(h, buf_t);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
trace(T_CRYPTO, "crypto: computing challenge check hash");
- trace(T_CRYPTO, "crypto: public key = %s", gestr(g, kpub));
- trace(T_CRYPTO, "crypto: receiver challenge = %s", gestr(g, cc));
- trace(T_CRYPTO, "crypto: sender challenge = %s", gestr(g, c));
- trace(T_CRYPTO, "crypto: sender reply = %s", gestr(g, y));
+ trace(T_CRYPTO, "crypto: public key = %s", g->ops->gestr(g, K));
+ trace(T_CRYPTO, "crypto: receiver challenge = %s", g->ops->gestr(g, CC));
+ trace(T_CRYPTO, "crypto: sender challenge = %s", g->ops->gestr(g, C));
+ trace(T_CRYPTO, "crypto: sender reply = %s", g->ops->gestr(g, Y));
trace_block(T_CRYPTO, "crypto: hash output", buf_t, kx->kpriv->algs.hashsz);
}))
GH_DESTROY(h);
@@ -231,7 +237,7 @@ static const octet *hashcheck(keyexch *kx, ge *kpub, ge *cc, ge *c, ge *y)
*
* Arguments: @keyexch *kx@ = pointer to key exchange block
* @buf *b@ = output buffer for challenge
- * @ge *c@ = peer's actual challenge
+ * @const dhge *C@ = peer's actual challenge
* @const octet *hc@ = peer's challenge cookie
*
* Returns: ---
@@ -239,12 +245,14 @@ static const octet *hashcheck(keyexch *kx, ge *kpub, ge *cc, ge *c, ge *y)
* Use: Writes a full challenge to the message buffer.
*/
-static void sendchallenge(keyexch *kx, buf *b, ge *c, const octet *hc)
+static void sendchallenge(keyexch *kx, buf *b,
+ const dhge *C, const octet *hc)
{
- G_TOBUF(kx->kpriv->g, b, kx->c);
+ const dhgrp *g = kx->kpriv->grp;
+ g->ops->stge(g, b, kx->C, DHFMT_VAR);
buf_put(b, hc, kx->kpriv->algs.hashsz);
- mpmask(b, kx->alpha, kx->kpriv->indexsz, kx->kpriv->algs.mgf,
- hashcheck(kx, kx->kpriv->kpub, c, kx->c, kx->rx),
+ mpmask(b, g, kx->a, g->scsz, kx->kpriv->algs.mgf,
+ hashcheck(kx, kx->kpriv->K, C, kx->C, kx->RX),
kx->kpriv->algs.hashsz);
}
@@ -269,24 +277,102 @@ static void timer(struct timeval *tv, void *v)
/* --- @settimer@ --- *
*
* Arguments: @keyexch *kx@ = pointer to key exchange context
- * @time_t t@ = when to set the timer for
+ * @struct timeval *tv@ = when to set the timer for
*
* Returns: ---
*
* Use: Sets the timer for the next key exchange attempt.
*/
-static void settimer(keyexch *kx, time_t t)
+static void settimer(keyexch *kx, struct timeval *tv)
{
- struct timeval tv;
- if (kx->f & KXF_TIMER)
- sel_rmtimer(&kx->t);
- tv.tv_sec = t;
- tv.tv_usec = 0;
- sel_addtimer(&sel, &kx->t, &tv, timer, kx);
+ if (kx->f & KXF_TIMER) sel_rmtimer(&kx->t);
+ sel_addtimer(&sel, &kx->t, tv, timer, kx);
kx->f |= KXF_TIMER;
}
+/* --- @f2tv@ --- *
+ *
+ * Arguments: @struct timeval *tv@ = where to write the timeval
+ * @double t@ = a time as a floating point number
+ *
+ * Returns: ---
+ *
+ * Use: Converts a floating-point time into a timeval.
+ */
+
+static void f2tv(struct timeval *tv, double t)
+{
+ tv->tv_sec = t;
+ tv->tv_usec = (t - tv->tv_sec)*MILLION;
+}
+
+/* --- @wobble@ --- *
+ *
+ * Arguments: @double t@ = a time interval
+ *
+ * Returns: The same time interval, with a random error applied.
+ */
+
+static double wobble(double t)
+{
+ uint32 r = rand_global.ops->word(&rand_global);
+ double w = (r/F_2P32) - 0.5;
+ return (t + t*w*T_WOBBLE);
+}
+
+/* --- @rs_time@ --- *
+ *
+ * Arguments: @retry *rs@ = current retry state
+ * @struct timeval *tv@ = where to write the result
+ * @const struct timeval *now@ = current time, or null
+ *
+ * Returns: ---
+ *
+ * Use: Computes a time at which to retry sending a key-exchange
+ * packet. This algorithm is subject to change, but it's
+ * currently a capped exponential backoff, slightly randomized
+ * to try to keep clients from hammering a server that's only
+ * just woken up.
+ *
+ * If @now@ is null then the function works out the time for
+ * itself.
+ */
+
+static void rs_time(retry *rs, struct timeval *tv, const struct timeval *now)
+{
+ double t;
+ struct timeval rtv;
+
+ if (!rs->t)
+ t = SEC(2);
+ else {
+ t = (rs->t * 5)/4;
+ if (t > MIN(5)) t = MIN(5);
+ }
+ rs->t = t;
+
+ if (!now) {
+ now = tv;
+ gettimeofday(tv, 0);
+ }
+ f2tv(&rtv, wobble(t));
+ TV_ADD(tv, now, &rtv);
+}
+
+/* --- @retry_reset@ --- *
+ *
+ * Arguments: @retry *rs@ = retry state
+ *
+ * Returns: --
+ *
+ * Use: Resets a retry state to indicate that progress has been
+ * made. Also useful for initializing the state in the first
+ * place.
+ */
+
+static void rs_reset(retry *rs) { rs->t = 0; }
+
/*----- Challenge management ----------------------------------------------*/
/* --- Notes on challenge management --- *
@@ -313,10 +399,11 @@ static void settimer(keyexch *kx, time_t t)
static void kxc_destroy(kxchal *kxc)
{
+ const dhgrp *g = kxc->kx->kpriv->grp;
if (kxc->f & KXF_TIMER)
sel_rmtimer(&kxc->t);
- G_DESTROY(kxc->kx->kpriv->g, kxc->c);
- G_DESTROY(kxc->kx->kpriv->g, kxc->r);
+ g->ops->freege(g, kxc->C);
+ g->ops->freege(g, kxc->R);
ks_drop(kxc->ks);
DESTROY(kxc);
}
@@ -346,6 +433,8 @@ static void kxc_stoptimer(kxchal *kxc)
* Returns: A pointer to the challenge block.
*
* Use: Returns a pointer to a new challenge block to fill in.
+ * In particular, the @c@ and @r@ members are left
+ * uninitialized.
*/
static kxchal *kxc_new(keyexch *kx)
@@ -365,31 +454,31 @@ static kxchal *kxc_new(keyexch *kx)
/* --- Fill in the new structure --- */
kxc = CREATE(kxchal);
- kxc->c = G_CREATE(kx->kpriv->g);
- kxc->r = G_CREATE(kx->kpriv->g);
kxc->ks = 0;
kxc->kx = kx;
kxc->f = 0;
kx->r[i] = kxc;
+ rs_reset(&kxc->rs);
return (kxc);
}
/* --- @kxc_bychal@ --- *
*
* Arguments: @keyexch *kx@ = pointer to key exchange block
- * @ge *c@ = challenge from remote host
+ * @const dhge *C@ = challenge from remote host
*
* Returns: Pointer to the challenge block, or null.
*
* Use: Finds a challenge block, given its challenge.
*/
-static kxchal *kxc_bychal(keyexch *kx, ge *c)
+static kxchal *kxc_bychal(keyexch *kx, const dhge *C)
{
+ const dhgrp *g = kx->kpriv->grp;
unsigned i;
for (i = 0; i < kx->nr; i++) {
- if (G_EQ(kx->kpriv->g, c, kx->r[i]->c))
+ if (g->ops->eq(g, C, kx->r[i]->C))
return (kx->r[i]);
}
return (0);
@@ -440,15 +529,16 @@ static void kxc_answer(keyexch *kx, kxchal *kxc)
{
stats *st = p_stats(kx->p);
buf *b = p_txstart(kx->p, MSG_KEYEXCH | KX_REPLY);
+ const dhgrp *g = kx->kpriv->grp;
struct timeval tv;
buf bb;
/* --- Build the reply packet --- */
T( trace(T_KEYEXCH, "keyexch: sending reply to `%s'", p_name(kx->p)); )
- sendchallenge(kx, b, kxc->c, kxc->hc);
+ sendchallenge(kx, b, kxc->C, kxc->hc);
buf_init(&bb, buf_i, sizeof(buf_i));
- G_TORAW(kx->kpriv->g, &bb, kxc->r);
+ g->ops->stge(g, &bb, kxc->R, DHFMT_STD);
buf_flip(&bb);
ks_encrypt(kxc->ks, MSG_KEYEXCH | KX_REPLY, &bb, b);
@@ -465,7 +555,7 @@ static void kxc_answer(keyexch *kx, kxchal *kxc)
if (kxc->f & KXF_TIMER)
sel_rmtimer(&kxc->t);
gettimeofday(&tv, 0);
- tv.tv_sec += T_RETRY;
+ rs_time(&kxc->rs, &tv, &tv);
sel_addtimer(&sel, &kxc->t, &tv, kxc_timer, kxc);
kxc->f |= KXF_TIMER;
}
@@ -485,7 +575,8 @@ static void kxc_answer(keyexch *kx, kxchal *kxc)
static int doprechallenge(keyexch *kx, buf *b)
{
stats *st = p_stats(kx->p);
- ge *c = G_CREATE(kx->kpriv->g);
+ const dhgrp *g = kx->kpriv->grp;
+ dhge *C = 0;
ghash *h;
/* --- Ensure that we're in a sensible state --- */
@@ -497,11 +588,11 @@ static int doprechallenge(keyexch *kx, buf *b)
/* --- Unpack the packet --- */
- if (G_FROMBUF(kx->kpriv->g, b, c) || BLEFT(b))
+ if ((C = g->ops->ldge(g, b, DHFMT_VAR)) == 0 || BLEFT(b))
goto bad;
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: challenge = %s", gestr(kx->kpriv->g, c));
+ trace(T_CRYPTO, "crypto: challenge = %s", g->ops->gestr(g, C));
}))
/* --- Send out a full challenge by return --- */
@@ -509,8 +600,8 @@ static int doprechallenge(keyexch *kx, buf *b)
b = p_txstart(kx->p, MSG_KEYEXCH | KX_CHAL);
h = GH_INIT(kx->kpriv->algs.h);
HASH_STRING(h, "tripe-cookie");
- hashge(h, kx->kpriv->g, c);
- sendchallenge(kx, b, c, GH_DONE(h, 0));
+ hashge(h, g, C);
+ sendchallenge(kx, b, C, GH_DONE(h, 0));
GH_DESTROY(h);
st->n_kxout++;
st->sz_kxout += BLEN(b);
@@ -518,11 +609,11 @@ static int doprechallenge(keyexch *kx, buf *b)
/* --- Done --- */
- G_DESTROY(kx->kpriv->g, c);
+ g->ops->freege(g, C);
return (0);
bad:
- if (c) G_DESTROY(kx->kpriv->g, c);
+ if (C) g->ops->freege(g, C);
return (-1);
}
@@ -540,15 +631,15 @@ bad:
static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
{
- group *g = kx->kpriv->g;
+ const dhgrp *g = kx->kpriv->grp;
const algswitch *algs = &kx->kpriv->algs;
- size_t ixsz = kx->kpriv->indexsz;
- ge *c = G_CREATE(g);
- ge *r = G_CREATE(g);
- ge *cc = G_CREATE(g);
+ size_t ixsz = g->scsz;
+ dhge *C = 0;
+ dhge *R = 0;
+ dhge *CC = 0;
const octet *hc, *ck;
size_t x, y, z;
- mp *cv = 0;
+ dhsc *c = 0;
kxchal *kxc;
ghash *h = 0;
buf bb;
@@ -556,14 +647,14 @@ static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
/* --- Unpack the packet --- */
- if (G_FROMBUF(g, b, c) ||
+ if ((C = g->ops->ldge(g, b, DHFMT_VAR)) == 0 ||
(hc = buf_get(b, algs->hashsz)) == 0 ||
(ck = buf_get(b, ixsz)) == 0) {
a_warn("KX", "?PEER", kx->p, "invalid", "%s", pkname[msg], A_END);
goto bad;
}
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: challenge = %s", gestr(g, c));
+ trace(T_CRYPTO, "crypto: challenge = %s", g->ops->gestr(g, C));
trace_block(T_CRYPTO, "crypto: cookie", hc, algs->hashsz);
trace_block(T_CRYPTO, "crypto: check-value", ck, ixsz);
}))
@@ -583,7 +674,7 @@ static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
* This will also find a challenge block and, if necessary, populate it.
*/
- if ((kxc = kxc_bychal(kx, c)) != 0) {
+ if ((kxc = kxc_bychal(kx, C)) != 0) {
h = GH_INIT(algs->h);
HASH_STRING(h, "tripe-check-hash");
GH_HASH(h, ck, ixsz);
@@ -594,31 +685,30 @@ static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
/* --- Compute the reply, and check the magic --- */
- G_EXP(g, r, c, kx->kpriv->kpriv);
- cv = mpunmask(MP_NEW, ck, ixsz, algs->mgf,
- hashcheck(kx, kx->kpub->kpub, kx->c, c, r),
- algs->hashsz);
+ R = g->ops->mul(g, kx->kpriv->k, C);
+ if ((c = mpunmask(g, ck, ixsz, algs->mgf,
+ hashcheck(kx, kx->kpub->K, kx->C, C, R),
+ algs->hashsz)) == 0)
+ goto badcheck;
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: computed reply = %s", gestr(g, r));
- trace(T_CRYPTO, "crypto: recovered log = %s", mpstr(cv));
+ trace(T_CRYPTO, "crypto: computed reply = %s", g->ops->gestr(g, R));
+ trace(T_CRYPTO, "crypto: recovered log = %s", g->ops->scstr(g, c));
}))
- if (MP_CMP(cv, >, g->r) ||
- (G_EXP(g, cc, g->g, cv),
- !G_EQ(g, c, cc)))
- goto badcheck;
+ CC = g->ops->mul(g, c, 0);
+ if (!g->ops->eq(g, CC, C)) goto badcheck;
/* --- Fill in a new challenge block --- */
kxc = kxc_new(kx);
- G_COPY(g, kxc->c, c);
- G_COPY(g, kxc->r, r);
+ kxc->C = C; C = 0;
+ kxc->R = R; R = 0;
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-check-hash");
GH_HASH(h, ck, ixsz);
GH_DONE(h, kxc->ck); GH_DESTROY(h);
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-cookie");
- hashge(h, g, kxc->c);
+ hashge(h, g, kxc->C);
GH_DONE(h, kxc->hc); GH_DESTROY(h);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
@@ -628,25 +718,25 @@ static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
/* --- Work out the shared key --- */
- G_EXP(g, r, c, kx->alpha);
+ R = g->ops->mul(g, kx->a, kxc->C);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: shared secret = %s", gestr(g, r));
+ trace(T_CRYPTO, "crypto: shared secret = %s", g->ops->gestr(g, R));
}))
/* --- Compute the switch messages --- */
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-switch-request");
- hashge(h, g, kx->c); hashge(h, g, kxc->c);
+ hashge(h, g, kx->C); hashge(h, g, kxc->C);
GH_DONE(h, kxc->hswrq_out); GH_DESTROY(h);
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-switch-confirm");
- hashge(h, g, kx->c); hashge(h, g, kxc->c);
+ hashge(h, g, kx->C); hashge(h, g, kxc->C);
GH_DONE(h, kxc->hswok_out); GH_DESTROY(h);
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-switch-request");
- hashge(h, g, kxc->c); hashge(h, g, kx->c);
+ hashge(h, g, kxc->C); hashge(h, g, kx->C);
GH_DONE(h, kxc->hswrq_in); GH_DESTROY(h);
h = GH_INIT(algs->h); HASH_STRING(h, "tripe-switch-confirm");
- hashge(h, g, kxc->c); hashge(h, g, kx->c);
+ hashge(h, g, kxc->C); hashge(h, g, kx->C);
GH_DONE(h, kxc->hswok_in); GH_DESTROY(h);
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
@@ -663,28 +753,28 @@ static kxchal *respond(keyexch *kx, unsigned msg, buf *b)
/* --- Create a new symmetric keyset --- */
buf_init(&bb, buf_o, sizeof(buf_o));
- G_TOBUF(g, &bb, kx->c); x = BLEN(&bb);
- G_TOBUF(g, &bb, kxc->c); y = BLEN(&bb);
- G_TOBUF(g, &bb, r); z = BLEN(&bb);
+ g->ops->stge(g, &bb, kx->C, DHFMT_HASH); x = BLEN(&bb);
+ g->ops->stge(g, &bb, kxc->C, DHFMT_HASH); y = BLEN(&bb);
+ g->ops->stge(g, &bb, R, DHFMT_HASH); z = BLEN(&bb);
assert(BOK(&bb));
kxc->ks = ks_gen(BBASE(&bb), x, y, z, kx->p);
}
- G_DESTROY(g, c);
- G_DESTROY(g, cc);
- G_DESTROY(g, r);
- mp_drop(cv);
+ if (C) g->ops->freege(g, C);
+ if (CC) g->ops->freege(g, CC);
+ if (R) g->ops->freege(g, R);
+ if (c) g->ops->freesc(g, c);
return (kxc);
badcheck:
a_warn("KX", "?PEER", kx->p, "bad-expected-reply-log", A_END);
goto bad;
bad:
- G_DESTROY(g, c);
- G_DESTROY(g, cc);
- G_DESTROY(g, r);
- mp_drop(cv);
+ if (C) g->ops->freege(g, C);
+ if (CC) g->ops->freege(g, CC);
+ if (R) g->ops->freege(g, R);
+ if (c) g->ops->freesc(g, c);
return (0);
}
@@ -734,6 +824,8 @@ static void resend(keyexch *kx)
kxchal *kxc;
buf bb;
stats *st = p_stats(kx->p);
+ struct timeval tv;
+ const dhgrp *g = kx->kpriv->grp;
buf *b;
switch (kx->s) {
@@ -741,7 +833,7 @@ static void resend(keyexch *kx)
T( trace(T_KEYEXCH, "keyexch: sending prechallenge to `%s'",
p_name(kx->p)); )
b = p_txstart(kx->p, MSG_KEYEXCH | KX_PRECHAL);
- G_TOBUF(kx->kpriv->g, b, kx->c);
+ g->ops->stge(g, b, kx->C, DHFMT_VAR);
break;
case KXS_COMMIT:
T( trace(T_KEYEXCH, "keyexch: sending switch request to `%s'",
@@ -751,7 +843,7 @@ static void resend(keyexch *kx)
buf_put(b, kx->hc, kx->kpriv->algs.hashsz);
buf_put(b, kxc->hc, kx->kpriv->algs.hashsz);
buf_init(&bb, buf_i, sizeof(buf_i));
- G_TORAW(kx->kpriv->g, &bb, kxc->r);
+ g->ops->stge(g, &bb, kxc->R, DHFMT_STD);
buf_put(&bb, kxc->hswrq_out, kx->kpriv->algs.hashsz);
buf_flip(&bb);
ks_encrypt(kxc->ks, MSG_KEYEXCH | KX_SWITCH, &bb, b);
@@ -776,8 +868,10 @@ static void resend(keyexch *kx)
p_txend(kx->p);
}
- if (kx->s < KXS_SWITCH)
- settimer(kx, time(0) + T_RETRY);
+ if (kx->s < KXS_SWITCH) {
+ rs_time(&kx->rs, &tv, 0);
+ settimer(kx, &tv);
+ }
}
/* --- @decryptrest@ --- *
@@ -821,26 +915,26 @@ static int decryptrest(keyexch *kx, kxchal *kxc, unsigned msg, buf *b)
static int checkresponse(keyexch *kx, unsigned msg, buf *b)
{
- group *g = kx->kpriv->g;
- ge *r = G_CREATE(g);
+ const dhgrp *g = kx->kpriv->grp;
+ dhge *R;
- if (G_FROMRAW(g, b, r)) {
+ if ((R = g->ops->ldge(g, b, DHFMT_STD)) == 0) {
a_warn("KX", "?PEER", kx->p, "invalid", "%s", pkname[msg], A_END);
goto bad;
}
IF_TRACING(T_KEYEXCH, IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: reply = %s", gestr(g, r));
+ trace(T_CRYPTO, "crypto: reply = %s", g->ops->gestr(g, R));
}))
- if (!G_EQ(g, r, kx->rx)) {
+ if (!g->ops->eq(g, R, kx->RX)) {
a_warn("KX", "?PEER", kx->p, "incorrect", "response", A_END);
goto bad;
}
- G_DESTROY(g, r);
+ g->ops->freege(g, R);
return (0);
bad:
- G_DESTROY(g, r);
+ if (R) g->ops->freege(g, R);
return (-1);
}
@@ -919,8 +1013,13 @@ bad:
static void kxfinish(keyexch *kx)
{
kxchal *kxc = kx->r[0];
+ struct timeval now, tv;
+
ks_activate(kxc->ks);
- settimer(kx, ks_tregen(kxc->ks));
+ gettimeofday(&now, 0);
+ f2tv(&tv, wobble(T_REGEN));
+ TV_ADD(&tv, &now, &tv);
+ settimer(kx, &tv);
kx->s = KXS_SWITCH;
a_notify("KXDONE", "?PEER", kx->p, A_END);
p_stats(kx->p)->t_kx = time(0);
@@ -1044,6 +1143,7 @@ bad:
static void stop(keyexch *kx)
{
+ const dhgrp *g = kx->kpriv->grp;
unsigned i;
if (kx->f & KXF_DEAD)
@@ -1053,9 +1153,9 @@ static void stop(keyexch *kx)
sel_rmtimer(&kx->t);
for (i = 0; i < kx->nr; i++)
kxc_destroy(kx->r[i]);
- mp_drop(kx->alpha);
- G_DESTROY(kx->kpriv->g, kx->c);
- G_DESTROY(kx->kpriv->g, kx->rx);
+ g->ops->freesc(g, kx->a);
+ g->ops->freege(g, kx->C);
+ g->ops->freege(g, kx->RX);
kx->t_valid = 0;
kx->f |= KXF_DEAD;
kx->f &= ~KXF_TIMER;
@@ -1075,31 +1175,32 @@ static void stop(keyexch *kx)
static void start(keyexch *kx, time_t now)
{
algswitch *algs = &kx->kpriv->algs;
- group *g = kx->kpriv->g;
+ const dhgrp *g = kx->kpriv->grp;
ghash *h;
assert(kx->f & KXF_DEAD);
kx->f &= ~(KXF_DEAD | KXF_CORK);
kx->nr = 0;
- kx->alpha = mprand_range(MP_NEW, g->r, &rand_global, 0);
- kx->c = G_CREATE(g); G_EXP(g, kx->c, g->g, kx->alpha);
- kx->rx = G_CREATE(g); G_EXP(g, kx->rx, kx->kpub->kpub, kx->alpha);
+ kx->a = g->ops->randsc(g);
+ kx->C = g->ops->mul(g, kx->a, 0);
+ kx->RX = g->ops->mul(g, kx->a, kx->kpub->K);
kx->s = KXS_CHAL;
kx->t_valid = now + T_VALID;
h = GH_INIT(algs->h);
HASH_STRING(h, "tripe-cookie");
- hashge(h, g, kx->c);
+ hashge(h, g, kx->C);
GH_DONE(h, kx->hc);
GH_DESTROY(h);
IF_TRACING(T_KEYEXCH, {
trace(T_KEYEXCH, "keyexch: creating new challenge");
IF_TRACING(T_CRYPTO, {
- trace(T_CRYPTO, "crypto: secret = %s", mpstr(kx->alpha));
- trace(T_CRYPTO, "crypto: challenge = %s", gestr(g, kx->c));
- trace(T_CRYPTO, "crypto: expected response = %s", gestr(g, kx->rx));
+ trace(T_CRYPTO, "crypto: secret = %s", g->ops->scstr(g, kx->a));
+ trace(T_CRYPTO, "crypto: challenge = %s", g->ops->gestr(g, kx->C));
+ trace(T_CRYPTO, "crypto: expected response = %s",
+ g->ops->gestr(g, kx->RX));
trace_block(T_CRYPTO, "crypto: challenge cookie",
kx->hc, algs->hashsz);
})
@@ -1176,23 +1277,26 @@ void kx_start(keyexch *kx, int forcep)
void kx_message(keyexch *kx, unsigned msg, buf *b)
{
- time_t now = time(0);
+ struct timeval now, tv;
stats *st = p_stats(kx->p);
size_t sz = BSZ(b);
int rc;
+ gettimeofday(&now, 0);
+ rs_reset(&kx->rs);
if (kx->f & KXF_CORK) {
- start(kx, now);
- settimer(kx, now + T_RETRY);
- a_notify("KXSTART", A_END);
+ start(kx, now.tv_sec);
+ rs_time(&kx->rs, &tv, &now);
+ settimer(kx, &tv);
+ a_notify("KXSTART", "?PEER", kx->p, A_END);
}
if (checkpub(kx))
return;
- if (!VALIDP(kx, now)) {
+ if (!VALIDP(kx, now.tv_sec)) {
stop(kx);
- start(kx, now);
+ start(kx, now.tv_sec);
}
T( trace(T_KEYEXCH, "keyexch: processing %s packet from `%s'",
msg < KX_NMSG ? pkname[msg] : "unknown", p_name(kx->p)); )
@@ -1347,7 +1451,8 @@ void kx_newkeys(keyexch *kx)
newkeys:
switchp = ((kx->f & KXF_DEAD) ||
kx->s != KXS_SWITCH ||
- !group_samep(kx->kpriv->g, kpriv->g));
+ kpriv->grp->ops != kx->kpriv->grp->ops ||
+ !kpriv->grp->ops->samegrpp(kpriv->grp, kx->kpriv->grp));
T( trace(T_KEYEXCH, "keyexch: peer `%s' adopting "
"%s priv `%s' and %s pub `%s'; %sforcing exchange", p_name(kx->p),
@@ -1383,11 +1488,11 @@ newkeys:
int kx_init(keyexch *kx, peer *p, keyset **ks, unsigned f)
{
- if ((kx->kpriv = km_findpriv(tag_priv)) == 0) goto fail_0;
+ if ((kx->kpriv = km_findpriv(p_privtag(p))) == 0) goto fail_0;
if ((kx->kpub = km_findpub(p_tag(p))) == 0) goto fail_1;
if (!km_samealgsp(kx->kpriv, kx->kpub)) {
- a_warn("KX", "?PEER", kx->p, "algorithms-mismatch",
- "local-private-key", "%s", tag_priv,
+ a_warn("KX", "?PEER", p, "group-mismatch",
+ "local-private-key", "%s", p_privtag(p),
"peer-public-key", "%s", p_tag(p),
A_END);
goto fail_2;
@@ -1396,6 +1501,7 @@ int kx_init(keyexch *kx, peer *p, keyset **ks, unsigned f)
kx->ks = ks;
kx->p = p;
kx->f = KXF_DEAD | KXF_PUBKEY | f;
+ rs_reset(&kx->rs);
if (!(kx->f & KXF_CORK)) {
start(kx, time(0));
resend(kx);