3 files changed, 86 insertions, 51 deletions

diff --git a/PROTOCOL.krl b/PROTOCOL.krl
index e8caa4527..b9695107b 100644
--- a/PROTOCOL.krl
+++ b/PROTOCOL.krl
@@ -37,7 +37,7 @@ The available section types are:
 #define KRL_SECTION_FINGERPRINT_SHA1            3
 #define KRL_SECTION_SIGNATURE                   4
 
-3. Certificate serial section
+2. Certificate section
 
 These sections use type KRL_SECTION_CERTIFICATES to revoke certificates by
 serial number or key ID. The consist of the CA key that issued the
@@ -47,6 +47,11 @@ ignored.
         string ca_key
         string reserved
 
+Where "ca_key" is the standard SSH wire serialisation of the CA's
+public key. Alternately, "ca_key" may be an empty string to indicate
+the certificate section applies to all CAs (this is most useful when
+revoking key IDs).
+
 Followed by one or more sections:
 
         byte    cert_section_type
@@ -161,4 +166,4 @@ Implementations that retrieve KRLs over untrusted channels must verify
 signatures. Signature sections are optional for KRLs distributed by
 trusted means.
 
-$OpenBSD: PROTOCOL.krl,v 1.2 2013/01/18 00:24:58 djm Exp $
+$OpenBSD: PROTOCOL.krl,v 1.3 2015/01/30 01:10:33 djm Exp $
diff --git a/krl.c b/krl.c
index 3fe29c8b1..4bbaa2080 100644
--- a/krl.c
+++ b/krl.c
@@ -14,7 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $OpenBSD: krl.c,v 1.30 2015/01/26 02:59:11 djm Exp $ */
+/* $OpenBSD: krl.c,v 1.31 2015/01/30 01:10:33 djm Exp $ */
 
 #include "includes.h"
 
@@ -156,8 +156,7 @@ revoked_certs_free(struct revoked_certs *rc)
                 free(rki->key_id);
                 free(rki);
         }
-        if (rc->ca_key != NULL)
-                sshkey_free(rc->ca_key);
+        sshkey_free(rc->ca_key);
 }
 
 void
@@ -214,7 +213,8 @@ revoked_certs_for_ca_key(struct ssh_krl *krl, const struct sshkey *ca_key,
 
         *rcp = NULL;
         TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
-                if (sshkey_equal(rc->ca_key, ca_key)) {
+                if ((ca_key == NULL && rc->ca_key == NULL) ||
+                    sshkey_equal(rc->ca_key, ca_key)) {
                         *rcp = rc;
                         return 0;
                 }
@@ -224,14 +224,17 @@ revoked_certs_for_ca_key(struct ssh_krl *krl, const struct sshkey *ca_key,
         /* If this CA doesn't exist in the list then add it now */
         if ((rc = calloc(1, sizeof(*rc))) == NULL)
                 return SSH_ERR_ALLOC_FAIL;
-        if ((r = sshkey_from_private(ca_key, &rc->ca_key)) != 0) {
+        if (ca_key == NULL)
+                rc->ca_key = NULL;
+        else if ((r = sshkey_from_private(ca_key, &rc->ca_key)) != 0) {
                 free(rc);
                 return r;
         }
         RB_INIT(&rc->revoked_serials);
         RB_INIT(&rc->revoked_key_ids);
         TAILQ_INSERT_TAIL(&krl->revoked_certs, rc, entry);
-        KRL_DBG(("%s: new CA %s", __func__, sshkey_type(ca_key)));
+        KRL_DBG(("%s: new CA %s", __func__,
+            ca_key == NULL ? "*" : sshkey_type(ca_key)));
         *rcp = rc;
         return 0;
 }
@@ -554,9 +557,15 @@ revoked_certs_generate(struct revoked_certs *rc, struct sshbuf *buf)
         if ((sect = sshbuf_new()) == NULL)
                 return SSH_ERR_ALLOC_FAIL;
 
-        /* Store the header: CA scope key, reserved */
-        if ((r = sshkey_puts(rc->ca_key, buf)) != 0 ||
-            (r = sshbuf_put_string(buf, NULL, 0)) != 0)
+        /* Store the header: optional CA scope key, reserved */
+        if (rc->ca_key == NULL) {
+                if ((r = sshbuf_put_string(buf, NULL, 0)) != 0)
+                        goto out;
+        } else {
+                if ((r = sshkey_puts(rc->ca_key, buf)) != 0)
+                        goto out;
+        }
+        if ((r = sshbuf_put_string(buf, NULL, 0)) != 0)
                 goto out;
 
         /* Store the revoked serials.  */
@@ -813,7 +822,7 @@ parse_revoked_certs(struct sshbuf *buf, struct ssh_krl *krl)
         if ((r = sshbuf_get_string_direct(buf, &blob, &blen)) != 0 ||
             (r = sshbuf_skip_string(buf)) != 0)
                 goto out;
-        if ((r = sshkey_from_blob(blob, blen, &ca_key)) != 0)
+        if (blen != 0 && (r = sshkey_from_blob(blob, blen, &ca_key)) != 0)
                 goto out;
 
         while (sshbuf_len(buf) > 0) {
@@ -1154,13 +1163,45 @@ ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
         return r;
 }
 
+/* Checks certificate serial number and key ID revocation */
+static int
+is_cert_revoked(const struct sshkey *key, struct revoked_certs *rc)
+{
+        struct revoked_serial rs, *ers;
+        struct revoked_key_id rki, *erki;
+
+        /* Check revocation by cert key ID */
+        memset(&rki, 0, sizeof(rki));
+        rki.key_id = key->cert->key_id;
+        erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki);
+        if (erki != NULL) {
+                KRL_DBG(("%s: revoked by key ID", __func__));
+                return SSH_ERR_KEY_REVOKED;
+        }
+
+        /*
+         * Legacy cert formats lack serial numbers. Zero serials numbers
+         * are ignored (it's the default when the CA doesn't specify one).
+         */
+        if (sshkey_cert_is_legacy(key) || key->cert->serial == 0)
+                return 0;
+
+        memset(&rs, 0, sizeof(rs));
+        rs.lo = rs.hi = key->cert->serial;
+        ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs);
+        if (ers != NULL) {
+                KRL_DBG(("%s: revoked serial %llu matched %llu:%llu", __func__,
+                    key->cert->serial, ers->lo, ers->hi));
+                return SSH_ERR_KEY_REVOKED;
+        }
+        return 0;
+}
+
 /* Checks whether a given key/cert is revoked. Does not check its CA */
 static int
 is_key_revoked(struct ssh_krl *krl, const struct sshkey *key)
 {
         struct revoked_blob rb, *erb;
-        struct revoked_serial rs, *ers;
-        struct revoked_key_id rki, *erki;
         struct revoked_certs *rc;
         int r;
 
@@ -1190,37 +1231,22 @@ is_key_revoked(struct ssh_krl *krl, const struct sshkey *key)
         if (!sshkey_is_cert(key))
                 return 0;
 
-        /* Check cert revocation */
+        /* Check cert revocation for the specified CA */
         if ((r = revoked_certs_for_ca_key(krl, key->cert->signature_key,
             &rc, 0)) != 0)
                 return r;
-        if (rc == NULL)
-                return 0; /* No entry for this CA */
-
-        /* Check revocation by cert key ID */
-        memset(&rki, 0, sizeof(rki));
-        rki.key_id = key->cert->key_id;
-        erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki);
-        if (erki != NULL) {
-                KRL_DBG(("%s: revoked by key ID", __func__));
-                return SSH_ERR_KEY_REVOKED;
+        if (rc != NULL) {
+                if ((r = is_cert_revoked(key, rc)) != 0)
+                        return r;
         }
-
-        /*
-         * Legacy cert formats lack serial numbers. Zero serials numbers
-         * are ignored (it's the default when the CA doesn't specify one).
-         */
-        if (sshkey_cert_is_legacy(key) || key->cert->serial == 0)
-                return 0;
-
-        memset(&rs, 0, sizeof(rs));
-        rs.lo = rs.hi = key->cert->serial;
-        ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs);
-        if (ers != NULL) {
-                KRL_DBG(("%s: revoked serial %llu matched %llu:%llu", __func__,
-                    key->cert->serial, ers->lo, ers->hi));
-                return SSH_ERR_KEY_REVOKED;
+        /* Check cert revocation for the wildcard CA */
+        if ((r = revoked_certs_for_ca_key(krl, NULL, &rc, 0)) != 0)
+                return r;
+        if (rc != NULL) {
+                if ((r = is_cert_revoked(key, rc)) != 0)
+                        return r;
         }
+
         KRL_DBG(("%s: %llu no match", __func__, key->cert->serial));
         return 0;
 }
diff --git a/ssh-keygen.c b/ssh-keygen.c
index b435498cb..2c6a56839 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-keygen.c,v 1.260 2015/01/30 00:59:19 djm Exp $ */
+/* $OpenBSD: ssh-keygen.c,v 1.261 2015/01/30 01:10:33 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1973,7 +1973,7 @@ load_krl(const char *path, struct ssh_krl **krlp)
 }
 
 static void
-update_krl_from_file(struct passwd *pw, const char *file,
+update_krl_from_file(struct passwd *pw, const char *file, int wild_ca,
     const struct sshkey *ca, struct ssh_krl *krl)
 {
         struct sshkey *key = NULL;
@@ -2015,7 +2015,7 @@ update_krl_from_file(struct passwd *pw, const char *file,
                 if (*cp == '\0')
                         continue;
                 if (strncasecmp(cp, "serial:", 7) == 0) {
-                        if (ca == NULL) {
+                        if (ca == NULL && !wild_ca) {
                                 fatal("revoking certificates by serial number "
                                     "requires specification of a CA key");
                         }
@@ -2052,7 +2052,7 @@ update_krl_from_file(struct passwd *pw, const char *file,
                                     __func__);
                         }
                 } else if (strncasecmp(cp, "id:", 3) == 0) {
-                        if (ca == NULL) {
+                        if (ca == NULL && !wild_ca) {
                                 fatal("revoking certificates by key ID "
                                     "requires specification of a CA key");
                         }
@@ -2103,7 +2103,7 @@ do_gen_krl(struct passwd *pw, int updating, int argc, char **argv)
         struct ssh_krl *krl;
         struct stat sb;
         struct sshkey *ca = NULL;
-        int fd, i, r;
+        int fd, i, r, wild_ca = 0;
         char *tmp;
         struct sshbuf *kbuf;
 
@@ -2117,11 +2117,15 @@ do_gen_krl(struct passwd *pw, int updating, int argc, char **argv)
                         fatal("KRL \"%s\" does not exist", identity_file);
         }
         if (ca_key_path != NULL) {
-                tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
-                if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
-                        fatal("Cannot load CA public key %s: %s",
-                            tmp, ssh_err(r));
-                free(tmp);
+                if (strcasecmp(ca_key_path, "none") == 0)
+                        wild_ca = 1;
+                else {
+                        tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
+                        if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
+                                fatal("Cannot load CA public key %s: %s",
+                                    tmp, ssh_err(r));
+                        free(tmp);
+                }
         }
 
         if (updating)
@@ -2135,7 +2139,7 @@ do_gen_krl(struct passwd *pw, int updating, int argc, char **argv)
                 ssh_krl_set_comment(krl, identity_comment);
 
         for (i = 0; i < argc; i++)
-                update_krl_from_file(pw, argv[i], ca, krl);
+                update_krl_from_file(pw, argv[i], wild_ca, ca, krl);
 
         if ((kbuf = sshbuf_new()) == NULL)
                 fatal("sshbuf_new failed");