Handle larger values with ASN1 INTEGER structure

src/ssl.c

@@ -18087,6 +18087,36 @@ WOLFSSL_X509_REVOKED* wolfSSL_sk_X509_REVOKED_value(
 }
 #endif
 
+/* Used to create a new WOLFSSL_ASN1_INTEGER structure.
+ * returns a pointer to new structure on success and NULL on failure
+ */
+WOLFSSL_ASN1_INTEGER* wolfSSL_ASN1_INTEGER_new(void)
+{
+    WOLFSSL_ASN1_INTEGER* a;
+
+    a = (WOLFSSL_ASN1_INTEGER*)XMALLOC(sizeof(WOLFSSL_ASN1_INTEGER), NULL,
+                                       DYNAMIC_TYPE_OPENSSL);
+    if (a == NULL) {
+        return NULL;
+    }
+
+    XMEMSET(a, 0, sizeof(WOLFSSL_ASN1_INTEGER));
+    a->data = a->intData;
+    return a;
+}
+
+
+/* free's internal elements of WOLFSSL_ASN1_INTEGER and free's "in" itself */
+void wolfSSL_ASN1_INTEGER_free(WOLFSSL_ASN1_INTEGER* in)
+{
+    if (in != NULL) {
+        if (in->isDynamic) {
+            XFREE(in->data, NULL, DYNAMIC_TYPE_OPENSSL);
+        }
+        XFREE(in, NULL, DYNAMIC_TYPE_OPENSSL);
+    }
+}
+
 
 WOLFSSL_ASN1_INTEGER* wolfSSL_X509_get_serialNumber(WOLFSSL_X509* x509)
 {
@@ -18095,19 +18125,24 @@ WOLFSSL_ASN1_INTEGER* wolfSSL_X509_get_serialNumber(WOLFSSL_X509* x509)
 
     WOLFSSL_ENTER("wolfSSL_X509_get_serialNumber");
 
-    a = (WOLFSSL_ASN1_INTEGER*)XMALLOC(sizeof(WOLFSSL_ASN1_INTEGER), NULL,
+    a = wolfSSL_ASN1_INTEGER_new();
-                                       DYNAMIC_TYPE_OPENSSL);
     if (a == NULL)
         return NULL;
 
     /* Make sure there is space for the data, ASN.1 type and length. */
-    if (x509->serialSz > (int)(sizeof(WOLFSSL_ASN1_INTEGER) - 2)) {
+    if (x509->serialSz > (WOLFSSL_ASN1_INTEGER_MAX - 2)) {
-        XFREE(a, NULL, DYNAMIC_TYPE_OPENSSL);
+        /* dynamicly create data buffer, +2 for type and length */
-        return NULL;
+        a->data = (unsigned char*)XMALLOC(x509->serialSz + 2, NULL,
+                DYNAMIC_TYPE_OPENSSL);
+        if (a->data == NULL) {
+            wolfSSL_ASN1_INTEGER_free(a);
+            return NULL;
+        }
+        a->isDynamic = 1;
     }
 
     a->data[i++] = ASN_INTEGER;
-    a->data[i++] = (unsigned char)x509->serialSz;
+    i += SetLength(x509->serialSz, a->data + i);
     XMEMCPY(&a->data[i], x509->serial, x509->serialSz);
 
     return a;

tests/api.c

@@ -17745,6 +17745,39 @@ static void test_wolfSSL_SHA256(void)
 #endif
 }
 
+static void test_wolfSSL_X509_get_serialNumber(void)
+{
+#if defined(OPENSSL_EXTRA) && !defined(NO_CERTS) && \
+    !defined(NO_RSA)
+    ASN1_INTEGER* a;
+    BIGNUM* bn;
+    X509*   x509;
+
+
+    printf(testingFmt, "wolfSSL_X509_get_serialNumber()");
+
+    AssertNotNull(x509 = wolfSSL_X509_load_certificate_file(svrCertFile,
+                                                      SSL_FILETYPE_PEM));
+    AssertNotNull(a = X509_get_serialNumber(x509));
+
+    /* check on value of ASN1 Integer */
+    AssertNotNull(bn = ASN1_INTEGER_to_BN(a, NULL));
+    AssertIntEQ(BN_get_word(bn), 1);
+
+    BN_free(bn);
+    ASN1_INTEGER_free(a);
+
+    /* hard test free'ing with dynamic buffer to make sure there is no leaks */
+    a = ASN1_INTEGER_new();
+    AssertNotNull(a->data = (unsigned char*)XMALLOC(100, NULL,
+                DYNAMIC_TYPE_OPENSSL));
+    a->isDynamic = 1;
+    ASN1_INTEGER_free(a);
+
+    printf(resultFmt, passed);
+#endif
+}
+
 static void test_no_op_functions(void)
 {
     #if defined(OPENSSL_EXTRA)
@@ -18589,6 +18622,7 @@ void ApiTest(void)
     test_wolfSSL_DH_1536_prime();
     test_wolfSSL_AES_ecb_encrypt();
     test_wolfSSL_SHA256();
+    test_wolfSSL_X509_get_serialNumber();
 
     /* test the no op functions for compatibility */
     test_no_op_functions();

wolfssl/openssl/ssl.h

@@ -379,6 +379,8 @@ typedef WOLFSSL_X509_STORE_CTX X509_STORE_CTX;
 #define ASN1_GENERALIZEDTIME_print   wolfSSL_ASN1_GENERALIZEDTIME_print
 #define ASN1_TIME_adj                wolfSSL_ASN1_TIME_adj
 
+#define ASN1_INTEGER_new wolfSSL_ASN1_INTEGER_new
+#define ASN1_INTEGER_free wolfSSL_ASN1_INTEGER_free
 #define ASN1_INTEGER_cmp wolfSSL_ASN1_INTEGER_cmp
 #define ASN1_INTEGER_get wolfSSL_ASN1_INTEGER_get
 #define ASN1_INTEGER_to_BN wolfSSL_ASN1_INTEGER_to_BN

wolfssl/ssl.h

@@ -182,11 +182,15 @@ typedef struct WOLFSSL_ASN1_BIT_STRING  WOLFSSL_ASN1_BIT_STRING;
 #define WOLFSSL_ASN1_UTCTIME          WOLFSSL_ASN1_TIME
 #define WOLFSSL_ASN1_GENERALIZEDTIME  WOLFSSL_ASN1_TIME
 
+#define WOLFSSL_ASN1_INTEGER_MAX 20
 struct WOLFSSL_ASN1_INTEGER {
     /* size can be increased set at 20 for tag, length then to hold at least 16
      * byte type */
-    unsigned char data[20];
+    unsigned char intData[WOLFSSL_ASN1_INTEGER_MAX];
     /* ASN_INTEGER | LENGTH | hex of number */
+
+    unsigned char* data;
+    byte isDynamic:1; /* flag for if data pointer dynamic (1 is yes 0 is no) */
 };
 
 struct WOLFSSL_ASN1_TIME {
@@ -927,6 +931,8 @@ WOLFSSL_API WOLFSSL_X509_REVOKED* wolfSSL_X509_CRL_get_REVOKED(WOLFSSL_X509_CRL*
 WOLFSSL_API WOLFSSL_X509_REVOKED* wolfSSL_sk_X509_REVOKED_value(
                                                       WOLFSSL_X509_REVOKED*,int);
 WOLFSSL_API WOLFSSL_ASN1_INTEGER* wolfSSL_X509_get_serialNumber(WOLFSSL_X509*);
+WOLFSSL_API void wolfSSL_ASN1_INTEGER_free(WOLFSSL_ASN1_INTEGER*);
+WOLFSSL_API WOLFSSL_ASN1_INTEGER* wolfSSL_ASN1_INTEGER_new(void);
 
 WOLFSSL_API int wolfSSL_ASN1_TIME_print(WOLFSSL_BIO*, const WOLFSSL_ASN1_TIME*);