Verify MFT and GBR objects only carry RFC 3779 extensions set to 'inherit'

OK claudio@ tb@

diff --git a/usr.sbin/rpki-client/extern.h b/usr.sbin/rpki-client/extern.h
index 3e1c3e4..53d0202 100644 (file)
--- a/usr.sbin/rpki-client/extern.h
+++ b/usr.sbin/rpki-client/extern.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: extern.h,v 1.136 2022/05/11 14:42:01 job Exp $ */
+/*     $OpenBSD: extern.h,v 1.137 2022/05/11 21:19:06 job Exp $ */
 /*
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -636,6 +636,7 @@ int          x509_get_time(const ASN1_TIME *, time_t *);
 char           *x509_convert_seqnum(const char *, const ASN1_INTEGER *);
 int             x509_location(const char *, const char *, const char *,
                    GENERAL_NAME *, char **);
+int             x509_inherits(X509 *);
 
 /* printers */
 char           *time2str(time_t);

diff --git a/usr.sbin/rpki-client/gbr.c b/usr.sbin/rpki-client/gbr.c
index 483a168..db0616f 100644 (file)
--- a/usr.sbin/rpki-client/gbr.c
+++ b/usr.sbin/rpki-client/gbr.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: gbr.c,v 1.15 2022/04/01 17:22:07 claudio Exp $ */
+/*     $OpenBSD: gbr.c,v 1.16 2022/05/11 21:19:06 job Exp $ */
 /*
  * Copyright (c) 2020 Claudio Jeker <claudio@openbsd.org>
  *
@@ -74,9 +74,15 @@ gbr_parse(X509 **x509, const char *fn, const unsigned char *der, size_t len)
                    "missing AIA, AKI or SKI X509 extension", fn);
                goto out;
        }
+
+       if (!x509_inherits(*x509)) {
+               warnx("%s: RFC 3779 extension not set to inherit", fn);
+               goto out;
+       }
+
        return p.res;
 
-out:
+ out:
        gbr_free(p.res);
        X509_free(*x509);
        *x509 = NULL;

diff --git a/usr.sbin/rpki-client/mft.c b/usr.sbin/rpki-client/mft.c
index b987593..2789ca0 100644 (file)
--- a/usr.sbin/rpki-client/mft.c
+++ b/usr.sbin/rpki-client/mft.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: mft.c,v 1.63 2022/05/10 07:41:37 tb Exp $ */
+/*     $OpenBSD: mft.c,v 1.64 2022/05/11 21:19:06 job Exp $ */
 /*
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -474,6 +474,11 @@ mft_parse(X509 **x509, const char *fn, const unsigned char *der, size_t len)
                goto out;
        }
 
+       if (!x509_inherits(*x509)) {
+               warnx("%s: RFC 3779 extension not set to inherit", fn);
+               goto out;
+       }
+
        /* get CRL info for later */
        if (!x509_get_crl(*x509, fn, &crldp))
                goto out;

diff --git a/usr.sbin/rpki-client/x509.c b/usr.sbin/rpki-client/x509.c
index cff78e5..0751b8e 100644 (file)
--- a/usr.sbin/rpki-client/x509.c
+++ b/usr.sbin/rpki-client/x509.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: x509.c,v 1.43 2022/05/10 10:52:09 job Exp $ */
+/*     $OpenBSD: x509.c,v 1.44 2022/05/11 21:19:06 job Exp $ */
 /*
  * Copyright (c) 2021 Claudio Jeker <claudio@openbsd.org>
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -348,6 +348,51 @@ x509_get_expire(X509 *x, const char *fn, time_t *tt)
 
 }
 
+/*
+ * Check whether the RFC 3779 extensions are set to inherit.
+ * Return 1 if both AS & IP are set to inherit.
+ * Return 0 on failure (such as missing extensions or no inheritance).
+ */
+int
+x509_inherits(X509 *x)
+{
+       STACK_OF(IPAddressFamily)       *addrblk = NULL;
+       ASIdentifiers                   *asidentifiers = NULL;
+       const IPAddressFamily           *af;
+       int                              i, rc = 0;
+
+       addrblk = X509_get_ext_d2i(x, NID_sbgp_ipAddrBlock, NULL, NULL);
+       if (addrblk == NULL)
+               goto out;
+
+       /*
+        * Check by hand, since X509v3_addr_inherits() success only means that
+        * at least one address family inherits, not all of them.
+        */
+       for (i = 0; i < sk_IPAddressFamily_num(addrblk); i++) {
+               af = sk_IPAddressFamily_value(addrblk, i);
+               if (af->ipAddressChoice->type != IPAddressChoice_inherit)
+                       goto out;
+       }
+
+       asidentifiers = X509_get_ext_d2i(x, NID_sbgp_autonomousSysNum, NULL,
+           NULL);
+       if (asidentifiers == NULL)
+               goto out;
+
+       /* We need to have AS numbers and don't want RDIs. */
+       if (asidentifiers->asnum == NULL || asidentifiers->rdi != NULL)
+               goto out;
+       if (!X509v3_asid_inherits(asidentifiers))
+               goto out;
+
+       rc = 1;
+ out:
+       ASIdentifiers_free(asidentifiers);
+       sk_IPAddressFamily_pop_free(addrblk, IPAddressFamily_free);
+       return rc;
+}
+
 /*
  * Parse the very specific subset of information in the CRL distribution
  * point extension.