Add appropriate lower bound checks for GeneralizedTime and UTCTime

ITU-T X.690 / ISO/IEC 8825-1 section 11.7 and section 11.8
impose specific constraints on how GeneralizedTime and UTCTime
can be encoded in BER/CER/DER. Following from these constraints
a minimum length can be derived.

Checking the length in this context can potentially help prevent
applications from interpreting an invalid GeneralizedTime as a
valid UTCTime.

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23483)

1 files changed, 53 insertions, 0 deletions

diff --git a/test/asn1_decode_test.c b/test/asn1_decode_test.c
index 9c676d3dcc..f112dd7034 100644
--- a/test/asn1_decode_test.c
+++ b/test/asn1_decode_test.c
@@ -11,6 +11,7 @@
 #include <string.h>
 
 #include <openssl/rand.h>
+#include <openssl/asn1.h>
 #include <openssl/asn1t.h>
 #include <openssl/obj_mac.h>
 #include "internal/numbers.h"
@@ -161,6 +162,56 @@ static int test_uint64(void)
     return 1;
 }
 
+/* GeneralizedTime underflow *********************************************** */
+
+static int test_gentime(void)
+{
+    /* Underflowing GeneralizedTime 161208193400Z (YYMMDDHHMMSSZ) */
+    const unsigned char der[] = {
+        0x18, 0x0d, 0x31, 0x36, 0x31, 0x32, 0x30, 0x38, 0x31,
+        0x39, 0x33, 0x34, 0x30, 0x30, 0x5a,
+    };
+    const unsigned char *p;
+    int der_len, rc = 1;
+    ASN1_GENERALIZEDTIME *gentime;
+
+    p = der;
+    der_len = sizeof(der);
+    gentime = d2i_ASN1_GENERALIZEDTIME(NULL, &p, der_len);
+
+    if (!TEST_ptr_null(gentime))
+        rc = 0; /* fail */
+
+    ASN1_GENERALIZEDTIME_free(gentime);
+    return rc;
+}
+
+/* UTCTime underflow ******************************************************* */
+
+static int test_utctime(void)
+{
+    /* Underflowing UTCTime 0205104700Z (MMDDHHMMSSZ) */
+    const unsigned char der[] = {
+        0x17, 0x0b, 0x30, 0x32, 0x30, 0x35, 0x31, 0x30,
+        0x34, 0x37, 0x30, 0x30, 0x5a,
+    };
+    const unsigned char *p;
+    int der_len, rc = 1;
+    ASN1_UTCTIME *utctime;
+
+    p = der;
+    der_len = sizeof(der);
+    utctime = d2i_ASN1_UTCTIME(NULL, &p, der_len);
+
+    if (!TEST_ptr_null(utctime))
+        rc = 0; /* fail */
+
+    ASN1_UTCTIME_free(utctime);
+    return rc;
+}
+
+/* Invalid template ******************************************************** */
+
 typedef struct {
     ASN1_STRING *invalidDirString;
 } INVALIDTEMPLATE;
@@ -229,6 +280,8 @@ int setup_tests(void)
     ADD_TEST(test_uint32);
     ADD_TEST(test_int64);
     ADD_TEST(test_uint64);
+    ADD_TEST(test_gentime);
+    ADD_TEST(test_utctime);
     ADD_TEST(test_invalid_template);
     ADD_TEST(test_reuse_asn1_object);
     return 1;