git: abd3a7939117 - releng/14.0 - openssl: Avoid type errors in EAI-related name check logic.
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Date: Wed, 04 Sep 2024 20:54:20 UTC
The branch releng/14.0 has been updated by emaste:
URL: https://cgit.FreeBSD.org/src/commit/?id=abd3a79391175d473c86476b10ae4f97f948f525
commit abd3a79391175d473c86476b10ae4f97f948f525
Author: Viktor Dukhovni <viktor@openssl.org>
AuthorDate: 2024-06-19 11:04:11 +0000
Commit: Ed Maste <emaste@FreeBSD.org>
CommitDate: 2024-09-04 20:54:03 +0000
openssl: Avoid type errors in EAI-related name check logic.
The incorrectly typed data is read only, used in a compare operation, so
neither remote code execution, nor memory content disclosure were possible.
However, applications performing certificate name checks were vulnerable to
denial of service.
The GENERAL_TYPE data type is a union, and we must take care to access the
correct member, based on `gen->type`, not all the member fields have the same
structure, and a segfault is possible if the wrong member field is read.
The code in question was lightly refactored with the intent to make it more
obviously correct.
Security: CVE-2024-6119
Obtained from: OpenSSL Project
(cherry picked from commit 1486960d6cdb052e4fc0109a56a0597b4e902ba1)
(cherry picked from commit 5946b0c6cbc77e6c5f62f5f7e635c6036e14f4d0)
Approved by: so
---
crypto/openssl/crypto/x509/v3_utl.c | 78 +++++++++++++++-------
.../test/recipes/25-test_eai_data/kdc-cert.pem | 21 ++++++
.../recipes/25-test_eai_data/kdc-root-cert.pem | 16 +++++
.../openssl/test/recipes/25-test_eai_data/kdc.sh | 41 ++++++++++++
4 files changed, 131 insertions(+), 25 deletions(-)
diff --git a/crypto/openssl/crypto/x509/v3_utl.c b/crypto/openssl/crypto/x509/v3_utl.c
index 6e4ef26ed608..304463d572c6 100644
--- a/crypto/openssl/crypto/x509/v3_utl.c
+++ b/crypto/openssl/crypto/x509/v3_utl.c
@@ -916,36 +916,64 @@ static int do_x509_check(X509 *x, const char *chk, size_t chklen,
ASN1_STRING *cstr;
gen = sk_GENERAL_NAME_value(gens, i);
- if ((gen->type == GEN_OTHERNAME) && (check_type == GEN_EMAIL)) {
- if (OBJ_obj2nid(gen->d.otherName->type_id) ==
- NID_id_on_SmtpUTF8Mailbox) {
- san_present = 1;
-
- /*
- * If it is not a UTF8String then that is unexpected and we
- * treat it as no match
- */
- if (gen->d.otherName->value->type == V_ASN1_UTF8STRING) {
- cstr = gen->d.otherName->value->value.utf8string;
-
- /* Positive on success, negative on error! */
- if ((rv = do_check_string(cstr, 0, equal, flags,
- chk, chklen, peername)) != 0)
- break;
- }
- } else
+ switch (gen->type) {
+ default:
+ continue;
+ case GEN_OTHERNAME:
+ switch (OBJ_obj2nid(gen->d.otherName->type_id)) {
+ default:
continue;
- } else {
- if ((gen->type != check_type) && (gen->type != GEN_OTHERNAME))
+ case NID_id_on_SmtpUTF8Mailbox:
+ /*-
+ * https://datatracker.ietf.org/doc/html/rfc8398#section-3
+ *
+ * Due to name constraint compatibility reasons described
+ * in Section 6, SmtpUTF8Mailbox subjectAltName MUST NOT
+ * be used unless the local-part of the email address
+ * contains non-ASCII characters. When the local-part is
+ * ASCII, rfc822Name subjectAltName MUST be used instead
+ * of SmtpUTF8Mailbox. This is compatible with legacy
+ * software that supports only rfc822Name (and not
+ * SmtpUTF8Mailbox). [...]
+ *
+ * SmtpUTF8Mailbox is encoded as UTF8String.
+ *
+ * If it is not a UTF8String then that is unexpected, and
+ * we ignore the invalid SAN (neither set san_present nor
+ * consider it a candidate for equality). This does mean
+ * that the subject CN may be considered, as would be the
+ * case when the malformed SmtpUtf8Mailbox SAN is instead
+ * simply absent.
+ *
+ * When CN-ID matching is not desirable, applications can
+ * choose to turn it off, doing so is at this time a best
+ * practice.
+ */
+ if (check_type != GEN_EMAIL
+ || gen->d.otherName->value->type != V_ASN1_UTF8STRING)
+ continue;
+ alt_type = 0;
+ cstr = gen->d.otherName->value->value.utf8string;
+ break;
+ }
+ break;
+ case GEN_EMAIL:
+ if (check_type != GEN_EMAIL)
continue;
- }
- san_present = 1;
- if (check_type == GEN_EMAIL)
cstr = gen->d.rfc822Name;
- else if (check_type == GEN_DNS)
+ break;
+ case GEN_DNS:
+ if (check_type != GEN_DNS)
+ continue;
cstr = gen->d.dNSName;
- else
+ break;
+ case GEN_IPADD:
+ if (check_type != GEN_IPADD)
+ continue;
cstr = gen->d.iPAddress;
+ break;
+ }
+ san_present = 1;
/* Positive on success, negative on error! */
if ((rv = do_check_string(cstr, alt_type, equal, flags,
chk, chklen, peername)) != 0)
diff --git a/crypto/openssl/test/recipes/25-test_eai_data/kdc-cert.pem b/crypto/openssl/test/recipes/25-test_eai_data/kdc-cert.pem
new file mode 100644
index 000000000000..e8a2c6f55d45
--- /dev/null
+++ b/crypto/openssl/test/recipes/25-test_eai_data/kdc-cert.pem
@@ -0,0 +1,21 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
diff --git a/crypto/openssl/test/recipes/25-test_eai_data/kdc-root-cert.pem b/crypto/openssl/test/recipes/25-test_eai_data/kdc-root-cert.pem
new file mode 100644
index 000000000000..a74c96bf3146
--- /dev/null
+++ b/crypto/openssl/test/recipes/25-test_eai_data/kdc-root-cert.pem
@@ -0,0 +1,16 @@
+-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
diff --git a/crypto/openssl/test/recipes/25-test_eai_data/kdc.sh b/crypto/openssl/test/recipes/25-test_eai_data/kdc.sh
new file mode 100755
index 000000000000..7a8dbc719fb7
--- /dev/null
+++ b/crypto/openssl/test/recipes/25-test_eai_data/kdc.sh
@@ -0,0 +1,41 @@
+#! /usr/bin/env bash
+
+# Create a root CA, signing a leaf cert with a KDC principal otherName SAN, and
+# also a non-UTF8 smtpUtf8Mailbox SAN followed by an rfc822Name SAN and a DNS
+# name SAN. In the vulnerable EAI code, the KDC principal `otherName` should
+# trigger ASAN errors in DNS name checks, while the non-UTF8 `smtpUtf8Mailbox`
+# should likewise lead to ASAN issues with email name checks.
+
+rm -f root-key.pem root-cert.pem
+openssl req -nodes -new -newkey rsa:2048 -keyout kdc-root-key.pem \
+ -x509 -subj /CN=Root -days 36524 -out kdc-root-cert.pem
+
+exts=$(
+ printf "%s\n%s\n%s\n%s = " \
+ "subjectKeyIdentifier = hash" \
+ "authorityKeyIdentifier = keyid" \
+ "basicConstraints = CA:false" \
+ "subjectAltName"
+ printf "%s, " "otherName:1.3.6.1.5.2.2;SEQUENCE:kdc_princ_name"
+ printf "%s, " "otherName:1.3.6.1.5.5.7.8.9;IA5:moe@example.com"
+ printf "%s, " "email:joe@example.com"
+ printf "%s\n" "DNS:mx1.example.com"
+ printf "[kdc_princ_name]\n"
+ printf "realm = EXP:0, GeneralString:TEST.EXAMPLE\n"
+ printf "principal_name = EXP:1, SEQUENCE:kdc_principal_seq\n"
+ printf "[kdc_principal_seq]\n"
+ printf "name_type = EXP:0, INTEGER:1\n"
+ printf "name_string = EXP:1, SEQUENCE:kdc_principal_components\n"
+ printf "[kdc_principal_components]\n"
+ printf "princ1 = GeneralString:krbtgt\n"
+ printf "princ2 = GeneralString:TEST.EXAMPLE\n"
+ )
+
+printf "%s\n" "$exts"
+
+openssl req -nodes -new -newkey rsa:2048 -keyout kdc-key.pem \
+ -subj "/CN=TEST.EXAMPLE" |
+ openssl x509 -req -out kdc-cert.pem \
+ -CA "kdc-root-cert.pem" -CAkey "kdc-root-key.pem" \
+ -set_serial 2 -days 36524 \
+ -extfile <(printf "%s\n" "$exts")