-
-#include "ec.h"
-#include "ec-keys.h"
-#include "dh.h"
-#include "gdsa.h"
-#include "gkcdsa.h"
-#include "rsa.h"
-
-#include "sha.h"
-#include "has160.h"
-
-/*----- Algorithm choice --------------------------------------------------*/
-
-/* --- Relevant type operations --- */
-
-typedef struct sig {
- const struct sigops *ops;
- key_packdef *kp;
- ghash *h;
-} sig;
-
-typedef struct sigops {
- const key_fetchdef *kf; /* Key fetching structure */
- size_t kdsz; /* Size of the key-data structure */
- sig *(*init)(key */*k*/, void */*kd*/, const gchash */*hc*/);
- int (*doit)(sig */*s*/, dstr */*d*/);
- void (*destroy)(sig */*s*/);
-} sigops;
-
-/* --- RSA PKCS1 --- */
-
-typedef struct rsap1_sigctx {
- sig s;
- rsa_privctx rp;
- pkcs1 p1;
-} rsap1_sigctx;
-
-static sig *rsap1_siginit(key *k, void *kd, const gchash *hc)
-{
- rsap1_sigctx *rs = CREATE(rsap1_sigctx);
- rsa_privcreate(&rs->rp, kd, &rand_global);
- rs->p1.r = &rand_global;
- rs->p1.ep = hc->name;
- rs->p1.epsz = strlen(hc->name) + 1;
- rs->s.h = 0;
- return (&rs->s);
-}
-
-static int rsap1_sigdoit(sig *s, dstr *d)
-{
- rsap1_sigctx *rs = (rsap1_sigctx *)s;
- size_t n;
- mp *m = rsa_sign(&rs->rp, MP_NEW,
- GH_DONE(s->h, 0), GH_CLASS(s->h)->hashsz,
- pkcs1_sigencode, &rs->p1);
- if (!m) return (-1);
- n = mp_octets(rs->rp.rp->n); dstr_ensure(d, n); mp_storeb(m, d->buf, n);
- d->len += n; mp_drop(m);
- return (0);
-}
-
-static void rsap1_sigdestroy(sig *s)
-{
- rsap1_sigctx *rs = (rsap1_sigctx *)s;
- DESTROY(rs);
-}
-
-static const sigops rsap1_sig = {
- rsa_privfetch, sizeof(rsa_priv),
- rsap1_siginit, rsap1_sigdoit, rsap1_sigdestroy
-};
-
-typedef struct rsap1_vrfctx {
- sig s;
- rsa_pubctx rp;
- pkcs1 p1;
-} rsap1_vrfctx;
-
-static sig *rsap1_vrfinit(key *k, void *kd, const gchash *hc)
-{
- rsap1_vrfctx *rv = CREATE(rsap1_vrfctx);
- rsa_pubcreate(&rv->rp, kd);
- rv->p1.r = &rand_global;
- rv->p1.ep = hc->name;
- rv->p1.epsz = strlen(hc->name) + 1;
- rv->s.h = 0;
- return (&rv->s);
-}
-
-static int rsap1_vrfdoit(sig *s, dstr *d)
-{
- rsap1_vrfctx *rv = (rsap1_vrfctx *)s;
- mp *m = mp_loadb(MP_NEW, d->buf, d->len);
- int rc = rsa_verify(&rv->rp, m,
- GH_DONE(s->h, 0), GH_CLASS(s->h)->hashsz,
- 0, pkcs1_sigdecode, &rv->p1);
- mp_drop(m);
- return (rc);
-}
-
-static void rsap1_vrfdestroy(sig *s)
-{
- rsap1_vrfctx *rv = (rsap1_vrfctx *)s;
- DESTROY(rv);
-}
-
-static const sigops rsap1_vrf = {
- rsa_pubfetch, sizeof(rsa_pub),
- rsap1_vrfinit, rsap1_vrfdoit, rsap1_vrfdestroy
-};
-
-/* --- RSA PSS --- */
-
-static const gccipher *getmgf(key *k, const gchash *hc)
-{
- dstr d = DSTR_INIT;
- const gccipher *gc;
- const char *mm;
-
- if ((mm = key_getattr(0, k, "mgf-alg")) == 0) {
- dstr_putf(&d, "%s-mgf", hc->name);
- mm = d.buf;
- }
- if ((gc = gcipher_byname(mm)) == 0)
- die(EXIT_FAILURE, "unknown encryption scheme `%s'", mm);
- dstr_destroy(&d);
- return (gc);
-}
-
-typedef struct rsapss_sigctx {
- sig s;
- rsa_privctx rp;
- pss p;
-} rsapss_sigctx;
-
-static sig *rsapss_siginit(key *k, void *kd, const gchash *hc)
-{
- rsapss_sigctx *rs = CREATE(rsapss_sigctx);
- rsa_privcreate(&rs->rp, kd, &rand_global);
- rs->p.r = &rand_global;
- rs->p.cc = getmgf(k, hc);
- rs->p.ch = hc;
- rs->p.ssz = hc->hashsz;
- return (&rs->s);
-}
-
-static int rsapss_sigdoit(sig *s, dstr *d)
-{
- rsapss_sigctx *rs = (rsapss_sigctx *)s;
- size_t n;
- mp *m = rsa_sign(&rs->rp, MP_NEW,
- GH_DONE(s->h, 0), GH_CLASS(s->h)->hashsz,
- pss_encode, &rs->p);
- if (!m) return (-1);
- n = mp_octets(rs->rp.rp->n); dstr_ensure(d, n); mp_storeb(m, d->buf, n);
- d->len += n; mp_drop(m);
- return (0);
-}
-
-static void rsapss_sigdestroy(sig *s)
-{
- rsapss_sigctx *rs = (rsapss_sigctx *)s;
- DESTROY(rs);
-}
-
-static const sigops rsapss_sig = {
- rsa_privfetch, sizeof(rsa_priv),
- rsapss_siginit, rsapss_sigdoit, rsapss_sigdestroy
-};
-
-typedef struct rsapss_vrfctx {
- sig s;
- rsa_pubctx rp;
- pss p;
-} rsapss_vrfctx;
-
-static sig *rsapss_vrfinit(key *k, void *kd, const gchash *hc)
-{
- rsapss_vrfctx *rv = CREATE(rsapss_vrfctx);
- rsa_pubcreate(&rv->rp, kd);
- rv->p.r = &rand_global;
- rv->p.cc = getmgf(k, hc);
- rv->p.ch = hc;
- rv->p.ssz = hc->hashsz;
- return (&rv->s);
-}
-
-static int rsapss_vrfdoit(sig *s, dstr *d)
-{
- rsapss_vrfctx *rv = (rsapss_vrfctx *)s;
- mp *m = mp_loadb(MP_NEW, d->buf, d->len);
- int rc = rsa_verify(&rv->rp, m,
- GH_DONE(s->h, 0), GH_CLASS(s->h)->hashsz,
- 0, pss_decode, &rv->p);
- mp_drop(m);
- return (rc);
-}
-
-static void rsapss_vrfdestroy(sig *s)
-{
- rsapss_vrfctx *rv = (rsapss_vrfctx *)s;
- DESTROY(rv);
-}
-
-static const sigops rsapss_vrf = {
- rsa_pubfetch, sizeof(rsa_pub),
- rsapss_vrfinit, rsapss_vrfdoit, rsapss_vrfdestroy
-};
-
-/* --- DSA and ECDSA --- */
-
-typedef struct dsa_sigctx {
- sig s;
- gdsa g;
-} dsa_sigctx;
-
-static void dsa_initcommon(dsa_sigctx *ds, const gchash *hc,
- const char *ktag)
-{
- ds->g.r = &rand_global;
- ds->g.h = hc;
- ds->g.u = MP_NEW;
- ds->s.h = 0;
-}
-
-static dsa_sigctx *dsa_doinit(key *k, const gprime_param *gp,
- mp *y, const gchash *hc)
-{
- dsa_sigctx *ds = CREATE(dsa_sigctx);
- dstr t = DSTR_INIT;
-
- key_fulltag(k, &t);
- if ((ds->g.g = group_prime(gp)) == 0)
- die(EXIT_FAILURE, "bad prime group in key `%s'", t.buf);
- ds->g.p = G_CREATE(ds->g.g);
- if (G_FROMINT(ds->g.g, ds->g.p, y))
- die(EXIT_FAILURE, "bad public key in key `%s'", t.buf);
- dsa_initcommon(ds, hc, t.buf);
- dstr_destroy(&t);
- return (ds);
-}
-
-static dsa_sigctx *ecdsa_doinit(key *k, const char *cstr,
- ec *y, const gchash *hc)
-{
- dsa_sigctx *ds = CREATE(dsa_sigctx);
- ec_info ei;
- const char *e;
- dstr t = DSTR_INIT;
-
- key_fulltag(k, &t);
- if ((e = ec_getinfo(&ei, cstr)) != 0)
- die(EXIT_FAILURE, "bad curve in key `%s': %s", t.buf, e);
- ds->g.g = group_ec(&ei);
- ds->g.p = G_CREATE(ds->g.g);
- if (G_FROMEC(ds->g.g, ds->g.p, y))
- die(EXIT_FAILURE, "bad public key in key `%s'", t.buf);
- dsa_initcommon(ds, hc, t.buf);
- dstr_destroy(&t);
- return (ds);
-}
-
-static sig *dsa_siginit(key *k, void *kd, const gchash *hc)
-{
- dh_priv *dp = kd;
- dsa_sigctx *ds = dsa_doinit(k, &dp->dp, dp->y, hc);
- ds->g.u = MP_COPY(dp->x);
- return (&ds->s);
-}
-
-static sig *ecdsa_siginit(key *k, void *kd, const gchash *hc)
-{
- ec_priv *ep = kd;
- dsa_sigctx *ds = ecdsa_doinit(k, ep->cstr, &ep->p, hc);
- ds->g.u = MP_COPY(ep->x);
- return (&ds->s);
-}
-
-static int dsa_sigdoit(sig *s, dstr *d)
-{
- dsa_sigctx *ds = (dsa_sigctx *)s;
- gdsa_sig ss = GDSA_SIG_INIT;
- size_t n = mp_octets(ds->g.g->r);
-
- gdsa_sign(&ds->g, &ss, GH_DONE(ds->s.h, 0), 0);
- dstr_ensure(d, 2 * n);
- mp_storeb(ss.r, d->buf, n);
- mp_storeb(ss.s, d->buf + n, n);
- d->len += 2 * n;
- mp_drop(ss.r); mp_drop(ss.s);
- return (0);
-}
-
-static void dsa_sigdestroy(sig *s)
-{
- dsa_sigctx *ds = (dsa_sigctx *)s;
- G_DESTROY(ds->g.g, ds->g.p);
- mp_drop(ds->g.u);
- G_DESTROYGROUP(ds->g.g);
-}
-
-static const sigops dsa_sig = {
- dh_privfetch, sizeof(dh_priv),
- dsa_siginit, dsa_sigdoit, dsa_sigdestroy
-};
-
-static const sigops ecdsa_sig = {
- ec_privfetch, sizeof(ec_priv),
- ecdsa_siginit, dsa_sigdoit, dsa_sigdestroy
-};
-
-static sig *dsa_vrfinit(key *k, void *kd, const gchash *hc)
-{
- dh_pub *dp = kd;
- dsa_sigctx *ds = dsa_doinit(k, &dp->dp, dp->y, hc);
- return (&ds->s);
-}
-
-static sig *ecdsa_vrfinit(key *k, void *kd, const gchash *hc)
-{
- ec_pub *ep = kd;
- dsa_sigctx *ds = ecdsa_doinit(k, ep->cstr, &ep->p, hc);
- return (&ds->s);
-}
-
-static int dsa_vrfdoit(sig *s, dstr *d)
-{
- dsa_sigctx *ds = (dsa_sigctx *)s;
- gdsa_sig ss;
- size_t n = d->len/2;
- int rc;
-
- ss.r = mp_loadb(MP_NEW, d->buf, n);
- ss.s = mp_loadb(MP_NEW, d->buf + n, d->len - n);
- rc = gdsa_verify(&ds->g, &ss, GH_DONE(ds->s.h, 0));
- mp_drop(ss.r); mp_drop(ss.s);
- return (rc);
-}
-
-static const sigops dsa_vrf = {
- dh_pubfetch, sizeof(dh_pub),
- dsa_vrfinit, dsa_vrfdoit, dsa_sigdestroy
-};
-
-static const sigops ecdsa_vrf = {
- ec_pubfetch, sizeof(ec_pub),
- ecdsa_vrfinit, dsa_vrfdoit, dsa_sigdestroy
-};
-
-/* --- KCDSA and ECKCDSA --- */
-
-static void kcdsa_privkey(dsa_sigctx *ds, mp *x)
- { ds->g.u = mp_modinv(MP_NEW, x, ds->g.g->r); }
-
-static void kcdsa_sethash(dsa_sigctx *ds, const gchash *hc)
- { ds->s.h = gkcdsa_beginhash(&ds->g); }
-
-static sig *kcdsa_siginit(key *k, void *kd, const gchash *hc)
-{
- dh_priv *dp = kd;
- dsa_sigctx *ds = dsa_doinit(k, &dp->dp, dp->y, hc);
- kcdsa_privkey(ds, dp->x);
- kcdsa_sethash(ds, hc);
- return (&ds->s);
-}
-
-static sig *eckcdsa_siginit(key *k, void *kd, const gchash *hc)
-{
- ec_priv *ep = kd;
- dsa_sigctx *ds = ecdsa_doinit(k, ep->cstr, &ep->p, hc);
- kcdsa_privkey(ds, ep->x);
- kcdsa_sethash(ds, hc);
- return (&ds->s);
-}
-
-static int kcdsa_sigdoit(sig *s, dstr *d)
-{
- dsa_sigctx *ds = (dsa_sigctx *)s;
- gkcdsa_sig ss = GKCDSA_SIG_INIT;
- size_t hsz = ds->g.h->hashsz, n = mp_octets(ds->g.g->r);
-
- gkcdsa_sign(&ds->g, &ss, GH_DONE(ds->s.h, 0), 0);
- dstr_ensure(d, hsz + n);
- memcpy(d->buf, ss.r, hsz);
- mp_storeb(ss.s, d->buf + hsz, n);
- d->len += hsz + n;
- xfree(ss.r); mp_drop(ss.s);
- return (0);
-}
-
-static const sigops kcdsa_sig = {
- dh_privfetch, sizeof(dh_priv),
- kcdsa_siginit, kcdsa_sigdoit, dsa_sigdestroy
-};
-
-static const sigops eckcdsa_sig = {
- ec_privfetch, sizeof(ec_priv),
- eckcdsa_siginit, kcdsa_sigdoit, dsa_sigdestroy
-};
-
-static sig *kcdsa_vrfinit(key *k, void *kd, const gchash *hc)
-{
- dh_pub *dp = kd;
- dsa_sigctx *ds = dsa_doinit(k, &dp->dp, dp->y, hc);
- kcdsa_sethash(ds, hc);
- return (&ds->s);
-}
-
-static sig *eckcdsa_vrfinit(key *k, void *kd, const gchash *hc)
-{
- ec_pub *ep = kd;
- dsa_sigctx *ds = ecdsa_doinit(k, ep->cstr, &ep->p, hc);
- kcdsa_sethash(ds, hc);
- return (&ds->s);
-}
-
-static int kcdsa_vrfdoit(sig *s, dstr *d)
-{
- dsa_sigctx *ds = (dsa_sigctx *)s;
- gkcdsa_sig ss;
- size_t hsz = ds->g.h->hashsz, n = d->len - hsz;
- int rc;
-
- if (d->len < hsz)
- return (-1);
- ss.r = (octet *)d->buf;
- ss.s = mp_loadb(MP_NEW, d->buf + hsz, n);
- rc = gkcdsa_verify(&ds->g, &ss, GH_DONE(ds->s.h, 0));
- mp_drop(ss.s);
- return (rc);
-}
-
-static const sigops kcdsa_vrf = {
- dh_pubfetch, sizeof(dh_pub),
- kcdsa_vrfinit, kcdsa_vrfdoit, dsa_sigdestroy
-};
-
-static const sigops eckcdsa_vrf = {
- ec_pubfetch, sizeof(ec_pub),
- eckcdsa_vrfinit, kcdsa_vrfdoit, dsa_sigdestroy
-};
-
-/* --- The switch table --- */
-
-static const struct sigtab {
- const char *name;
- const sigops *signops;
- const sigops *verifyops;
- const gchash *ch;
-} sigtab[] = {
- { "rsapkcs1", &rsap1_sig, &rsap1_vrf, &sha },
- { "rsapss", &rsapss_sig, &rsapss_vrf, &sha },
- { "dsa", &dsa_sig, &dsa_vrf, &sha },
- { "ecdsa", &ecdsa_sig, &ecdsa_vrf, &sha },
- { "kcdsa", &kcdsa_sig, &kcdsa_vrf, &has160 },
- { "eckcdsa", &eckcdsa_sig, &eckcdsa_vrf, &has160 },
- { 0, 0, 0 }
-};
-
-/* --- @getsig@ --- *
- *
- * Arguments: @key *k@ = the key to load
- * @int wantpriv@ = nonzero if we want to sign
- *
- * Returns: A signature-making thing.
- *
- * Use: Loads a key and starts hashing.
- */
-
-static sig *getsig(key *k, int wantpriv)
-{
- const char *salg, *halg = 0;
- dstr d = DSTR_INIT;
- dstr t = DSTR_INIT;
- char *p = 0;
- const char *q;
- sig *s;
- const struct sigtab *st;
- const sigops *so;
- const gchash *ch;
- void *kd;
- int e;
- key_packdef *kp;
-
- /* --- Setup stuff --- */
-
- key_fulltag(k, &t);
-
- /* --- Get the signature algorithm --- *
- *
- * Take the attribute if it's there; otherwise use the key type.
- */
-
- if ((q = key_getattr(0, k, "sig-alg")) != 0) {
- dstr_puts(&d, q);
- p = d.buf;
- } else if (strncmp(k->type, "dsig-", 5) == 0 && k->type[5]) {
- dstr_puts(&d, k->type);
- p = d.buf + 5;
- } else
- die(EXIT_FAILURE, "no signature algorithm for key `%s'", t.buf);
-
- /* --- Grab the hash algorithm --- *
- *
- * Grab it from the signature algorithm if it's there. But override that
- * from the attribute.
- */
-
- salg = p;
- if ((p = strchr(p, '-')) != 0) {
- *p++ = 0;
- halg = p;
- }
- if ((q = key_getattr(0, k, "hash-alg")) != 0)
- halg = q;
-
- /* --- Look up the algorithms in the table --- */
-
- for (st = sigtab; st->name; st++) {
- if (strcmp(st->name, salg) == 0)
- goto s_found;
- }
- die(EXIT_FAILURE, "signature algorithm `%s' not found in key `%s'",
- salg, t.buf);
-s_found:;
- if (!halg)
- ch = st->ch;
- else {
- if ((ch = ghash_byname(halg)) == 0) {
- die(EXIT_FAILURE, "hash algorithm `%s' not found in key `%s'",
- halg, t.buf);
- }
- }
- so = wantpriv ? st->signops : st->verifyops;
-
- /* --- Load the key --- */
-
- kd = xmalloc(so->kdsz);
- kp = key_fetchinit(so->kf, 0, kd);
- if ((e = key_fetch(kp, k)) != 0)
- die(EXIT_FAILURE, "error fetching key `%s': %s", t.buf, key_strerror(e));
- s = so->init(k, kd, ch);
- if (!s->h)
- s->h = GH_INIT(ch);
- s->kp = kp;
- s->ops = so;
-
- /* --- Free stuff up --- */
-
- dstr_destroy(&d);
- dstr_destroy(&t);
- return (s);
-}
-
-/* --- @freesig@ --- *
- *
- * Arguments: @sig *s@ = signature-making thing
- *
- * Returns: ---
- *
- * Use: Frees up a signature-making thing
- */
-
-static void freesig(sig *s)
-{
- GH_DESTROY(s->h);
- key_fetchdone(s->kp);
- s->ops->destroy(s);
-}