ipa-kdb: initial support for passkeys

- added passkey detection based on the presence of ipaPassKey attribute
  in the LDAP entry of the principal
- added 'passkey' authentication indicator
- added support for enforcing KDC policy based on the 'passkey'
  indicator

Fixes: https://pagure.io/freeipa/issue/9263
Signed-off-by: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

daemons/ipa-kdb/ipa_kdb.c

@@ -200,6 +200,7 @@ static const struct {
     { "pkinit", IPADB_USER_AUTH_PKINIT },
     { "hardened", IPADB_USER_AUTH_HARDENED },
     { "idp", IPADB_USER_AUTH_IDP },
+    { "passkey", IPADB_USER_AUTH_PASSKEY },
     { }
 };
 

daemons/ipa-kdb/ipa_kdb.h

@@ -106,6 +106,7 @@ enum ipadb_user_auth {
   IPADB_USER_AUTH_PKINIT   = 1 << 4,
   IPADB_USER_AUTH_HARDENED = 1 << 5,
   IPADB_USER_AUTH_IDP      = 1 << 6,
+  IPADB_USER_AUTH_PASSKEY  = 1 << 7,
 };
 
 enum ipadb_user_auth_idx {
@@ -114,6 +115,7 @@ enum ipadb_user_auth_idx {
   IPADB_USER_AUTH_IDX_PKINIT,
   IPADB_USER_AUTH_IDX_HARDENED,
   IPADB_USER_AUTH_IDX_IDP,
+  IPADB_USER_AUTH_IDX_PASSKEY,
   IPADB_USER_AUTH_IDX_MAX,
 };
 

daemons/ipa-kdb/ipa_kdb_kdcpolicy.c

@@ -143,6 +143,15 @@ ipa_kdcpolicy_check_as(krb5_context context, krb5_kdcpolicy_moddata moddata,
                 goto done;
             }
             pol_limits = &(ied->pol_limits[IPADB_USER_AUTH_IDX_IDP]);
+        } else if (strcmp(auth_indicator, "passkey") == 0) {
+            valid_auth_indicators++;
+            /* Allow hardened even if only password pre-auth is allowed */
+            if (!(ua & IPADB_USER_AUTH_PASSKEY)) {
+                *status = "Passkey pre-authentication not allowed for this user.";
+                kerr = KRB5KDC_ERR_POLICY;
+                goto done;
+            }
+            pol_limits = &(ied->pol_limits[IPADB_USER_AUTH_IDX_PASSKEY]);
         }
     }
 

daemons/ipa-kdb/ipa_kdb_principals.c

@@ -78,6 +78,7 @@ static char *std_principal_attrs[] = {
     IPA_USER_AUTH_TYPE,
     "ipatokenRadiusConfigLink",
     "ipaIdpConfigLink",
+    "ipaPassKey",
     "krbAuthIndMaxTicketLife",
     "krbAuthIndMaxRenewableAge",
     "ipaNTSecurityIdentifier",
@@ -396,6 +397,25 @@ static void ipadb_validate_idp(struct ipadb_context *ipactx,
         ldap_value_free_len(vals);
 }
 
+static void ipadb_validate_passkey(struct ipadb_context *ipactx,
+                               LDAPMessage *lentry,
+                               enum ipadb_user_auth *ua)
+{
+    struct berval **vals;
+
+    if (!(*ua & IPADB_USER_AUTH_PASSKEY))
+        return;
+
+    /* Ensure that the user has a link to an IdP config. */
+    vals = ldap_get_values_len(ipactx->lcontext, lentry,
+                               "ipaPassKey");
+    if (vals == NULL || vals[0] == NULL)
+        *ua &= ~IPADB_USER_AUTH_PASSKEY;
+
+    if (vals != NULL)
+        ldap_value_free_len(vals);
+}
+
 static enum ipadb_user_auth ipadb_get_user_auth(struct ipadb_context *ipactx,
                                                 LDAPMessage *lentry)
 {
@@ -429,6 +449,7 @@ static enum ipadb_user_auth ipadb_get_user_auth(struct ipadb_context *ipactx,
     ipadb_validate_otp(ipactx, lentry, &ua);
     ipadb_validate_radius(ipactx, lentry, &ua);
     ipadb_validate_idp(ipactx, lentry, &ua);
+    ipadb_validate_passkey(ipactx, lentry, &ua);
 
     return ua;
 }
@@ -613,6 +634,8 @@ static void ipadb_parse_authind_policies(krb5_context kcontext,
          IPADB_USER_AUTH_HARDENED, IPADB_USER_AUTH_IDX_HARDENED},
         {"krbAuthIndMaxTicketLife;idp",
          IPADB_USER_AUTH_IDP, IPADB_USER_AUTH_IDX_IDP},
+        {"krbAuthIndMaxTicketLife;passkey",
+         IPADB_USER_AUTH_PASSKEY, IPADB_USER_AUTH_IDX_PASSKEY},
 	    {NULL, IPADB_USER_AUTH_NONE, IPADB_USER_AUTH_IDX_MAX},
     }, age_authind_map[] = {
         {"krbAuthIndMaxRenewableAge;otp",
@@ -625,6 +648,8 @@ static void ipadb_parse_authind_policies(krb5_context kcontext,
          IPADB_USER_AUTH_HARDENED, IPADB_USER_AUTH_IDX_HARDENED},
         {"krbAuthIndMaxRenewableAge;idp",
          IPADB_USER_AUTH_IDP, IPADB_USER_AUTH_IDX_IDP},
+        {"krbAuthIndMaxRenewableAge;passkey",
+         IPADB_USER_AUTH_PASSKEY, IPADB_USER_AUTH_IDX_PASSKEY},
         {NULL, IPADB_USER_AUTH_NONE, IPADB_USER_AUTH_IDX_MAX},
     };
 
@@ -668,6 +693,7 @@ static krb5_error_code ipadb_parse_ldap_entry(krb5_context kcontext,
     const krb5_octet rad_string[] = "otp\0[{\"indicators\": [\"radius\"]}]";
     const krb5_octet otp_string[] = "otp\0[{\"indicators\": [\"otp\"]}]";
     const krb5_octet idp_string[] = "idp\0[{\"type\":\"oauth2\",\"indicators\": [\"idp\"]}]";
+    const krb5_octet passkey_string[] = "passkey\0[{\"indicators\": [\"passkey\"]}]";
     struct ipadb_context *ipactx;
     enum ipadb_user_auth ua;
     LDAP *lcontext;
@@ -1052,6 +1078,11 @@ static krb5_error_code ipadb_parse_ldap_entry(krb5_context kcontext,
                                  sizeof(idp_string), idp_string);
         if (kerr)
             goto done;
+    } else if (ua & IPADB_USER_AUTH_PASSKEY) {
+        kerr = ipadb_set_tl_data(entry, KRB5_TL_STRING_ATTRS,
+                                 sizeof(passkey_string), passkey_string);
+        if (kerr)
+            goto done;
     }
 
     if (ua & ~IPADB_USER_AUTH_NONE) {