3 files changed, 347 insertions, 19 deletions

diff --git a/src/lib/libcrypto/x509/x509_verify.c b/src/lib/libcrypto/x509/x509_verify.c
index 83030672ef..aa14bc1933 100644
--- a/src/lib/libcrypto/x509/x509_verify.c
+++ b/src/lib/libcrypto/x509/x509_verify.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: x509_verify.c,v 1.57 2022/06/27 14:10:22 tb Exp $ */
+/* $OpenBSD: x509_verify.c,v 1.58 2022/06/28 07:56:34 beck Exp $ */
 /*
  * Copyright (c) 2020-2021 Bob Beck <beck@openbsd.org>
  *
@@ -258,6 +258,25 @@ x509_verify_cert_self_signed(X509 *cert)
         return (cert->ex_flags & EXFLAG_SS) ? 1 : 0;
 }
 
+/* XXX beck - clean up this mess of is_root */
+static int
+x509_verify_check_chain_end(X509 *cert, int full_chain)
+{
+        if (full_chain)
+                return x509_verify_cert_self_signed(cert);
+        return 1;
+}
+
+static int
+x509_verify_check_legacy_chain_end(struct x509_verify_ctx *ctx, X509 *cert,
+    int full_chain)
+{
+        if (X509_check_trust(cert, ctx->xsc->param->trust, 0) !=
+            X509_TRUST_TRUSTED)
+                return 0;
+        return x509_verify_check_chain_end(cert, full_chain);
+}
+
 static int
 x509_verify_ctx_cert_is_root(struct x509_verify_ctx *ctx, X509 *cert,
     int full_chain)
@@ -273,15 +292,16 @@ x509_verify_ctx_cert_is_root(struct x509_verify_ctx *ctx, X509 *cert,
                 if ((match = x509_vfy_lookup_cert_match(ctx->xsc,
                     cert)) != NULL) {
                         X509_free(match);
-                        return !full_chain ||
-                            x509_verify_cert_self_signed(cert);
+                        return x509_verify_check_legacy_chain_end(ctx, cert,
+                            full_chain);
+
                 }
         } else {
                 /* Check the provided roots */
                 for (i = 0; i < sk_X509_num(ctx->roots); i++) {
                         if (X509_cmp(sk_X509_value(ctx->roots, i), cert) == 0)
-                                return !full_chain ||
-                                    x509_verify_cert_self_signed(cert);
+                                return x509_verify_check_chain_end(cert,
+                                    full_chain);
                 }
         }
 
@@ -393,14 +413,23 @@ x509_verify_ctx_validate_legacy_chain(struct x509_verify_ctx *ctx,
         ctx->xsc->error = X509_V_OK;
         ctx->xsc->error_depth = 0;
 
-        trust = x509_vfy_check_trust(ctx->xsc);
-        if (trust == X509_TRUST_REJECTED)
-                goto err;
-
         if (!x509_verify_ctx_set_xsc_chain(ctx, chain, 0, 1))
                 goto err;
 
         /*
+         * Call the legacy code to walk the chain and check trust
+         * in the legacy way to handle partial chains and get the
+         * callback fired correctly.
+         */
+        trust = x509_vfy_check_trust(ctx->xsc);
+        if (trust == X509_TRUST_REJECTED)
+                goto err; /* callback was called in x509_vfy_check_trust */
+        if (trust != X509_TRUST_TRUSTED) {
+                /* NOTREACHED */
+                goto err;  /* should not happen if we get in here - abort? */
+        }
+
+        /*
          * XXX currently this duplicates some work done in chain
          * build, but we keep it here until we have feature parity
          */
@@ -432,10 +461,6 @@ x509_verify_ctx_validate_legacy_chain(struct x509_verify_ctx *ctx,
         if (!x509_vfy_check_policy(ctx->xsc))
                 goto err;
 
-        if ((!(ctx->xsc->param->flags & X509_V_FLAG_PARTIAL_CHAIN)) &&
-            trust != X509_TRUST_TRUSTED)
-                goto err;
-
         ret = 1;
 
  err:
@@ -688,8 +713,8 @@ x509_verify_build_chains(struct x509_verify_ctx *ctx, X509 *cert,
                 }
                 if (ret > 0) {
                         if (x509_verify_potential_parent(ctx, candidate, cert)) {
-                                is_root = !full_chain ||
-                                    x509_verify_cert_self_signed(candidate);
+                                is_root = x509_verify_check_legacy_chain_end(
+                                    ctx, candidate, full_chain);
                                 x509_verify_consider_candidate(ctx, cert,
                                     is_root, candidate, current_chain,
                                     full_chain, name);
@@ -701,8 +726,8 @@ x509_verify_build_chains(struct x509_verify_ctx *ctx, X509 *cert,
                 for (i = 0; i < sk_X509_num(ctx->roots); i++) {
                         candidate = sk_X509_value(ctx->roots, i);
                         if (x509_verify_potential_parent(ctx, candidate, cert)) {
-                                is_root = !full_chain ||
-                                    x509_verify_cert_self_signed(candidate);
+                                is_root = x509_verify_check_chain_end(candidate,
+                                    full_chain);
                                 x509_verify_consider_candidate(ctx, cert,
                                     is_root, candidate, current_chain,
                                     full_chain, name);
@@ -1168,6 +1193,8 @@ x509_verify(struct x509_verify_ctx *ctx, X509 *leaf, char *name)
                                  * on failure and will be needed for
                                  * that.
                                  */
+                                ctx->xsc->error = ctx->error;
+                                ctx->xsc->error_depth = ctx->error_depth;
                                 if (!x509_verify_ctx_save_xsc_error(ctx)) {
                                         x509_verify_chain_free(current_chain);
                                         goto err;
diff --git a/src/regress/lib/libcrypto/x509/Makefile b/src/regress/lib/libcrypto/x509/Makefile
index ca66df19cd..4635d63ed0 100644
--- a/src/regress/lib/libcrypto/x509/Makefile
+++ b/src/regress/lib/libcrypto/x509/Makefile
@@ -1,7 +1,7 @@
-#       $OpenBSD: Makefile,v 1.13 2022/06/25 20:01:43 beck Exp $
+#       $OpenBSD: Makefile,v 1.14 2022/06/28 07:56:34 beck Exp $
 
 PROGS = constraints verify x509attribute x509name x509req_ext callback
-PROGS += expirecallback
+PROGS += expirecallback callbackfailures
 LDADD = -lcrypto
 DPADD = ${LIBCRYPTO}
 
@@ -20,6 +20,7 @@ REGRESS_TARGETS += regress-x509name
 REGRESS_TARGETS += regress-x509req_ext
 REGRESS_TARGETS += regress-callback
 REGRESS_TARGETS += regress-expirecallback
+REGRESS_TARGETS += regress-callbackfailures
 
 CLEANFILES +=   x509name.result callbackout
 
@@ -54,4 +55,7 @@ regress-callback: callback
 regress-expirecallback: expirecallback
         ./expirecallback ${.CURDIR}/../certs
 
+regress-callbackfailures: callbackfailures
+        ./callbackfailures ${.CURDIR}/../certs
+
 .include <bsd.regress.mk>
diff --git a/src/regress/lib/libcrypto/x509/callbackfailures.c b/src/regress/lib/libcrypto/x509/callbackfailures.c
new file mode 100644
index 0000000000..f714adffff
--- /dev/null
+++ b/src/regress/lib/libcrypto/x509/callbackfailures.c
@@ -0,0 +1,297 @@
+/* $OpenBSD: callbackfailures.c,v 1.1 2022/06/28 07:56:34 beck Exp $ */
+/*
+ * Copyright (c) 2020 Joel Sing <jsing@openbsd.org>
+ * Copyright (c) 2020-2021 Bob Beck <beck@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <err.h>
+#include <string.h>
+
+#include <openssl/bio.h>
+#include <openssl/err.h>
+#include <openssl/pem.h>
+#include <openssl/x509.h>
+#include <openssl/x509v3.h>
+#include <openssl/x509_verify.h>
+
+#define MODE_MODERN_VFY         0
+#define MODE_MODERN_VFY_DIR     1
+#define MODE_LEGACY_VFY         2
+#define MODE_VERIFY             3
+
+static int verbose = 1;
+
+static int expected_depth;
+static int expected_error;
+static int seen_depth;
+static int seen_error;
+
+static int
+passwd_cb(char *buf, int size, int rwflag, void *u)
+{
+        memset(buf, 0, size);
+        return (0);
+}
+
+static int
+certs_from_file(const char *filename, STACK_OF(X509) **certs, int clear)
+{
+        STACK_OF(X509_INFO) *xis = NULL;
+        STACK_OF(X509) *xs = NULL;
+        BIO *bio = NULL;
+        X509 *x;
+        int i;
+
+        if (clear) {
+                if ((xs = sk_X509_new_null()) == NULL)
+                        errx(1, "failed to create X509 stack");
+        } else
+                xs = *certs;
+        if ((bio = BIO_new_file(filename, "r")) == NULL) {
+                ERR_print_errors_fp(stderr);
+                errx(1, "failed to create bio");
+        }
+        if ((xis = PEM_X509_INFO_read_bio(bio, NULL, passwd_cb, NULL)) == NULL)
+                errx(1, "failed to read PEM");
+
+        for (i = 0; i < sk_X509_INFO_num(xis); i++) {
+                if ((x = sk_X509_INFO_value(xis, i)->x509) == NULL)
+                        continue;
+                if (!sk_X509_push(xs, x))
+                        errx(1, "failed to push X509");
+                X509_up_ref(x);
+        }
+
+        *certs = xs;
+        xs = NULL;
+
+        sk_X509_INFO_pop_free(xis, X509_INFO_free);
+        sk_X509_pop_free(xs, X509_free);
+        BIO_free(bio);
+
+        return 1;
+}
+
+static int
+verify_cert_cb(int ok, X509_STORE_CTX *xsc)
+{
+        X509 *current_cert;
+        int verify_err;
+
+        current_cert = X509_STORE_CTX_get_current_cert(xsc);
+        if (current_cert != NULL) {
+                X509_NAME_print_ex_fp(stderr,
+                    X509_get_subject_name(current_cert), 0,
+                    XN_FLAG_ONELINE);
+                fprintf(stderr, "\n");
+        }
+
+        verify_err = X509_STORE_CTX_get_error(xsc);
+        if (verify_err != X509_V_OK) {
+                seen_depth = X509_STORE_CTX_get_error_depth(xsc);
+                seen_error = verify_err;
+                fprintf(stderr, "verify error at depth %d: %s\n",
+                    X509_STORE_CTX_get_error_depth(xsc),
+                    X509_verify_cert_error_string(verify_err));
+        }
+
+        fprintf(stderr, "chain of length %d\n", sk_X509_num (X509_STORE_CTX_get0_chain (xsc)));
+
+        return ok;
+}
+
+static void
+verify_cert(const char *roots_dir, const char *roots_file,
+    const char *bundle_file, const char*bundle_file2, int *chains, int mode)
+{
+        STACK_OF(X509) *roots = NULL, *bundle = NULL;
+        X509_STORE_CTX *xsc = NULL;
+        X509_STORE *store = NULL;
+        int verify_err, use_dir;
+        X509 *leaf = NULL;
+
+        *chains = 0;
+        use_dir = (mode == MODE_MODERN_VFY_DIR);
+
+        if (!use_dir && !certs_from_file(roots_file, &roots, 1))
+                errx(1, "failed to load roots from '%s'", roots_file);
+        if (!certs_from_file(bundle_file, &bundle, 1))
+                errx(1, "failed to load bundle from '%s'", bundle_file);
+        if (!certs_from_file(bundle_file, &bundle, 0))
+                errx(1, "failed to load bundle from '%s'", bundle_file2);
+        if (sk_X509_num(bundle) < 1)
+                errx(1, "not enough certs in bundle");
+        leaf = sk_X509_shift(bundle);
+
+        if ((xsc = X509_STORE_CTX_new()) == NULL)
+                errx(1, "X509_STORE_CTX");
+        if (use_dir && (store = X509_STORE_new()) == NULL)
+                errx(1, "X509_STORE");
+        if (!X509_STORE_CTX_init(xsc, store, leaf, bundle)) {
+                ERR_print_errors_fp(stderr);
+                errx(1, "failed to init store context");
+        }
+
+        if (use_dir) {
+                if (!X509_STORE_load_locations(store, NULL, roots_dir))
+                        errx(1, "failed to set by_dir directory of %s", roots_dir);
+        }
+        if (mode == MODE_LEGACY_VFY)
+                X509_STORE_CTX_set_flags(xsc, X509_V_FLAG_LEGACY_VERIFY);
+        else
+                X509_VERIFY_PARAM_clear_flags(X509_STORE_CTX_get0_param(xsc),
+                    X509_V_FLAG_LEGACY_VERIFY);
+
+        if (verbose)
+                X509_STORE_CTX_set_verify_cb(xsc, verify_cert_cb);
+        if (!use_dir)
+                X509_STORE_CTX_set0_trusted_stack(xsc, roots);
+
+        if (X509_verify_cert(xsc) == 1) {
+                *chains = 1; /* XXX */
+                goto done;
+        }
+
+        verify_err = X509_STORE_CTX_get_error(xsc);
+        if (verify_err == 0)
+                errx(1, "Error unset on failure!\n");
+
+        fprintf(stderr, "failed to verify at %d: %s\n",
+            X509_STORE_CTX_get_error_depth(xsc),
+            X509_verify_cert_error_string(verify_err));
+
+ done:
+        sk_X509_pop_free(roots, X509_free);
+        sk_X509_pop_free(bundle, X509_free);
+        X509_STORE_free(store);
+        X509_STORE_CTX_free(xsc);
+        X509_free(leaf);
+}
+
+struct verify_cert_test {
+        const char *id;
+        int want_chains;
+        int failing;
+        int depth;
+        int error;
+};
+
+struct verify_cert_test verify_cert_tests[] = {
+        {
+                .id = "1a",
+                .want_chains = 0,
+                .depth = 0,
+                .error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
+        },
+        {
+                .id = "2a",
+                .want_chains = 0,
+                .depth = 1,
+                .error = X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY,
+        },
+        {
+                .id = "2c",
+                .want_chains = 0,
+                .depth = 2,
+                .error = X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN,
+        },
+};
+
+#define N_VERIFY_CERT_TESTS \
+    (sizeof(verify_cert_tests) / sizeof(*verify_cert_tests))
+
+static int
+verify_cert_test(const char *certs_path, int mode)
+{
+        char *roots_file, *bundle_file, *bundle_file2, *roots_dir;
+        struct verify_cert_test *vct;
+        int failed = 0;
+        int chains;
+        size_t i;
+
+        for (i = 0; i < N_VERIFY_CERT_TESTS; i++) {
+                vct = &verify_cert_tests[i];
+
+                if (asprintf(&roots_file, "/etc/ssl/cert.pem") == -1)
+                        errx(1, "asprintf");
+                if (asprintf(&bundle_file, "%s/%s/bundle.pem", certs_path,
+                    vct->id) == -1)
+                        errx(1, "asprintf");
+                if (asprintf(&bundle_file2, "%s/%s/roots.pem", certs_path,
+                    vct->id) == -1)
+                        errx(1, "asprintf");
+                if (asprintf(&roots_dir, "./%s/roots", vct->id) == -1)
+                        errx(1, "asprintf");
+
+                fprintf(stderr, "== Test %zu (%s)\n", i, vct->id);
+                fprintf(stderr, "== depth %d\n", vct->depth);
+                fprintf(stderr, "== error %d\n", vct->error);
+                expected_depth = vct->depth;
+                expected_error = vct->error;
+                verify_cert(roots_dir, roots_file, bundle_file, bundle_file2, &chains, mode);
+                if (chains == 0 && vct->want_chains == 0) {
+                        if (seen_error != expected_error) {
+                                fprintf(stderr, "FAIL: expected error %d, got %d\n",
+                                    seen_error, expected_error);
+                                failed |= 1;
+                        }
+                        if (seen_depth != expected_depth) {
+                                fprintf(stderr, "FAIL: expected depth %d, got %d\n",
+                                    seen_depth, expected_depth);
+                                failed |= 1;
+                        }
+                }
+
+                if ((mode == MODE_VERIFY && chains == vct->want_chains) ||
+                    (chains == 0 && vct->want_chains == 0) ||
+                    (chains == 1 && vct->want_chains > 0)) {
+                        fprintf(stderr, "INFO: Succeeded with %d chains%s\n",
+                            chains, vct->failing ? " (legacy failure)" : "");
+                        if (mode == MODE_LEGACY_VFY && vct->failing)
+                                failed |= 1;
+                } else {
+                        fprintf(stderr, "FAIL: Failed with %d chains%s\n",
+                            chains, vct->failing ? " (legacy failure)" : "");
+                        if (!vct->failing)
+                                failed |= 1;
+                }
+                fprintf(stderr, "\n");
+
+                free(roots_file);
+                free(bundle_file);
+                free(bundle_file2);
+                free(roots_dir);
+        }
+
+        return failed;
+}
+
+int
+main(int argc, char **argv)
+{
+        int failed = 0;
+
+        if (argc != 2) {
+                fprintf(stderr, "usage: %s <certs_path>\n", argv[0]);
+                exit(1);
+        }
+
+        fprintf(stderr, "\n\nTesting legacy x509_vfy\n");
+        failed |= verify_cert_test(argv[1], MODE_LEGACY_VFY);
+        fprintf(stderr, "\n\nTesting modern x509_vfy\n");
+        failed |= verify_cert_test(argv[1], MODE_MODERN_VFY);
+
+        return (failed);
+}