server/: Make bulk crypto transforms responsible for algorithm selection.

[tripe] / server / keymgmt.c

diff --git a/server/keymgmt.c b/server/keymgmt.c
index 837bc6e..2324f15 100644 (file)
--- a/server/keymgmt.c
+++ b/server/keymgmt.c
@@ -178,8 +178,7 @@ static const kgops *kgtab[] = {
 static int algs_get(algswitch *a, dstr *e, key_file *kf, key *k)
 {
   const char *p;
-  const bulkops *bulk;
-  char *q, *qq;
+  const bulkops *bops;
   dstr d = DSTR_INIT, dd = DSTR_INIT;
   int rc = -1;
 
@@ -206,83 +205,13 @@ static int algs_get(algswitch *a, dstr *e, key_file *kf, key *k)
   /* --- Bulk crypto transform --- */
 
   if ((p = key_getattr(kf, k, "bulk")) == 0) p = "v0";
-  for (bulk = bulktab; bulk->name && strcmp(p, bulk->name) != 0; bulk++);
-  if (!bulk->name) {
+  for (bops = bulktab; bops->name && strcmp(p, bops->name) != 0; bops++);
+  if (!bops->name) {
     a_format(e, "unknown-bulk-transform", "%s", p, A_END);
     goto done;
   }
-  a->bulk = bulk;
-
-  /* --- Symmetric encryption for bulk data --- */
-
-  if (!(a->bulk->prim & BCP_CIPHER))
-    a->c = 0;
-  else {
-    if ((p = key_getattr(kf, k, "cipher")) == 0) p = "blowfish-cbc";
-    if ((a->c = gcipher_byname(p)) == 0) {
-      a_format(e, "unknown-cipher", "%s", p, A_END);
-      goto done;
-    }
-  }
-
-  /* --- Block cipher for miscellaneous use --- */
-
-  if (!(a->bulk->prim & BCP_BLKC))
-    a->b = 0;
-  else {
-    if ((p = key_getattr(kf, k, "blkc")) == 0) {
-      dstr_reset(&dd);
-      dstr_puts(&dd, a->c ? a->c->name : "rijndael-");
-      if ((q = strrchr(dd.buf, '-')) != 0) *q = 0;
-      p = dd.buf;
-    }
-    dstr_reset(&d);
-    dstr_putf(&d, "%s-ecb", p);
-    if ((a->b = gcipher_byname(d.buf)) == 0) {
-      a_format(e, "unknown-blkc", "%s", p, A_END);
-      goto done;
-    }
-  }
-
-  /* --- Message authentication for bulk data --- */
-
-  if (!(a->bulk->prim & BCP_MAC)) {
-    a->m = 0;
-    a->tagsz = 0;
-  } else {
-    if ((p = key_getattr(kf, k, "mac")) != 0) {
-      dstr_reset(&d);
-      dstr_puts(&d, p);
-      if ((q = strchr(d.buf, '/')) != 0)
-       *q++ = 0;
-      if ((a->m = gmac_byname(d.buf)) == 0) {
-       a_format(e, "unknown-mac", "%s", d.buf, A_END);
-       goto done;
-      }
-      if (!q)
-       a->tagsz = a->m->hashsz;
-      else {
-       unsigned long n = strtoul(q, &qq, 0);
-       if (*qq)  {
-         a_format(e, "bad-tag-length-string", "%s", q, A_END);
-         goto done;
-       }
-       if (n%8 || n/8 > a->m->hashsz) {
-         a_format(e, "bad-tag-length", "%lu", n, A_END);
-         goto done;
-       }
-       a->tagsz = n/8;
-      }
-    } else {
-      dstr_reset(&d);
-      dstr_putf(&d, "%s-hmac", a->h->name);
-      if ((a->m = gmac_byname(d.buf)) == 0) {
-       a_format(e, "no-hmac-for-hash", "%s", a->h->name, A_END);
-       goto done;
-      }
-      a->tagsz = a->h->hashsz/2;
-    }
-  }
+  if ((a->bulk = bops->getalgs(a, e, kf, k)) == 0) goto done;
+  a->bulk->ops = bops;
 
   /* --- All done --- */
 
@@ -309,43 +238,7 @@ done:
 
 static int algs_check(algswitch *a, dstr *e, const group *g)
 {
-  /* --- Check the bulk crypto transform --- */
-
-  if (a->bulk->check(a, e)) return (-1);
-
-  /* --- Derive the key sizes --- *
-   *
-   * Must ensure that we have non-empty keys.  This isn't ideal, but it
-   * provides a handy sanity check.  Also must be based on a 64- or 128-bit
-   * block cipher or we can't do the data expiry properly.
-   */
-
   a->hashsz = a->h->hashsz;
-  if (a->c && (a->cksz = keysz(a->hashsz, a->c->keysz)) == 0) {
-    a_format(e, "cipher", "%s", a->c->name,
-            "no-key-size", "%lu", (unsigned long)a->hashsz,
-            A_END);
-    return (-1);
-  }
-  if (a->m && (a->mksz = keysz(a->hashsz, a->m->keysz)) == 0) {
-    a_format(e, "mac", "%s", a->m->name,
-            "no-key-size", "%lu", (unsigned long)a->hashsz,
-            A_END);
-    return (-1);
-  }
-  if (a->b && (a->bksz = keysz(a->hashsz, a->b->keysz)) == 0) {
-    a_format(e, "blkc", "%.*s", strlen(a->b->name) - 4, a->b->name,
-            "no-key-size", "%lu", (unsigned long)a->hashsz,
-            A_END);
-    return (-1);
-  }
-
-  /* --- Derive the data limit --- */
-
-  if (a->c && a->c->blksz < 16) a->expsz = MEG(64);
-  else a->expsz = MEG(2048);
-
-  /* --- Ensure the MGF accepts hashes as keys --- */
 
   if (keysz(a->hashsz, a->mgf->keysz) != a->hashsz) {
     a_format(e, "mgf", "%s", a->mgf->name,
@@ -354,7 +247,7 @@ static int algs_check(algswitch *a, dstr *e, const group *g)
     return (-1);
   }
 
-  /* --- All ship-shape and Bristol-fashion --- */
+  if (a->bulk->ops->checkalgs(a->bulk, a, e)) return (-1);
 
   return (0);
 }
@@ -374,10 +267,9 @@ int km_samealgsp(const kdata *kdx, const kdata *kdy)
   const algswitch *a = &kdx->algs, *aa = &kdy->algs;
 
   return (group_samep(kdx->g, kdy->g) &&
-         a->bulk == aa->bulk &&
-         a->c == aa->c && a->b == aa->b &&
          a->mgf == aa->mgf && a->h == aa->h &&
-         a->m == aa->m && a->tagsz == aa->tagsz);
+         a->bulk->ops == aa->bulk->ops &&
+         a->bulk->ops->samealgsp(a->bulk, aa->bulk));
 }
 
 /*----- Key data and key nodes --------------------------------------------*/
@@ -624,11 +516,7 @@ foundko:
       trace(T_CRYPTO, "crypto: h = %s", mpstr(kd->g->h));
       if (kd->kpriv)
        trace(T_CRYPTO, "crypto: x = %s", mpstr(kd->kpriv));
-      trace(T_CRYPTO, "crypto: cipher = %s", kd->algs.c->name);
-      trace(T_CRYPTO, "crypto: mgf = %s", kd->algs.mgf->name);
-      trace(T_CRYPTO, "crypto: hash = %s", kd->algs.h->name);
-      trace(T_CRYPTO, "crypto: mac = %s/%lu",
-           kd->algs.m->name, (unsigned long)kd->algs.tagsz * 8);
+      kd->algs.bulk->ops->tracealgs(kd->algs.bulk);
     })
   })