From c99ecf1bb49e2fbd0bf30a7b357cf06407b9588a Mon Sep 17 00:00:00 2001

From: Robbie Harwood <rharwood@redhat.com>

Date: Sat, 15 May 2021 18:04:58 -0400

Subject: [PATCH] Remove deprecated OpenSSL calls from softpkcs11

Rewrite add_pubkey_info() in terms of the EVP_PKEY interface.  In this

process, fix its unchecked allocations and fail fast for non-RSA keys.

(cherry picked from commit d6bf42279675100e3e4fe7c6e08eef74d49624cb)

(cherry picked from commit 5072bfdfaddae762680d0f9d97afa6dbf8274760)

---

 src/configure.ac            |   1 +

 src/tests/softpkcs11/main.c | 106 ++++++++++++++++++++++++------------

 2 files changed, 72 insertions(+), 35 deletions(-)

diff --git a/src/configure.ac b/src/configure.ac

index 3e1052db7..eb6307468 100644

--- a/src/configure.ac

+++ b/src/configure.ac

@@ -1114,6 +1114,7 @@ int i = 1;

 ])], k5_cv_openssl_version_okay=yes, k5_cv_openssl_version_okay=no)])

   old_LIBS="$LIBS"

   AC_CHECK_LIB(crypto, PKCS7_get_signer_info)

+  AC_CHECK_FUNCS(EVP_PKEY_get_bn_param)

   LIBS="$old_LIBS"

 fi

 if test "$k5_cv_openssl_version_okay" = yes && (test "$enable_pkinit" = yes || test "$enable_pkinit" = try); then

diff --git a/src/tests/softpkcs11/main.c b/src/tests/softpkcs11/main.c

index caa537b68..86b4ef711 100644

--- a/src/tests/softpkcs11/main.c

+++ b/src/tests/softpkcs11/main.c

@@ -413,47 +413,83 @@ add_object_attribute(struct st_object *o,

     return CKR_OK;

 }

+#ifdef HAVE_EVP_PKEY_GET_BN_PARAM

+

+/* Declare owner pointers since EVP_PKEY_get_bn_param() gives us copies. */

+#define DECLARE_BIGNUM(name) BIGNUM *name = NULL

+#define RELEASE_BIGNUM(bn) BN_clear_free(bn)

 static CK_RV

-add_pubkey_info(struct st_object *o, CK_KEY_TYPE key_type, EVP_PKEY *key)

+get_bignums(EVP_PKEY *key, BIGNUM **n, BIGNUM **e)

 {

-    switch (key_type) {

-    case CKK_RSA: {

-        CK_BYTE *modulus = NULL;

-        size_t modulus_len = 0;

-        CK_ULONG modulus_bits = 0;

-        CK_BYTE *exponent = NULL;

-        size_t exponent_len = 0;

-        const RSA *rsa;

-        const BIGNUM *n, *e;

+    if (EVP_PKEY_get_bn_param(key, "n", n) == 0 ||

+        EVP_PKEY_get_bn_param(key, "e", e) == 0)

+        return CKR_DEVICE_ERROR;

-        rsa = EVP_PKEY_get0_RSA(key);

-        RSA_get0_key(rsa, &n, &e, NULL);

-        modulus_bits = BN_num_bits(n);

-

-        modulus_len = BN_num_bytes(n);

-        modulus = malloc(modulus_len);

-        BN_bn2bin(n, modulus);

-

-        exponent_len = BN_num_bytes(e);

-        exponent = malloc(exponent_len);

-        BN_bn2bin(e, exponent);

-

-        add_object_attribute(o, 0, CKA_MODULUS, modulus, modulus_len);

-        add_object_attribute(o, 0, CKA_MODULUS_BITS,

-                             &modulus_bits, sizeof(modulus_bits));

-        add_object_attribute(o, 0, CKA_PUBLIC_EXPONENT,

-                             exponent, exponent_len);

-

-        free(modulus);

-        free(exponent);

-    }

-    default:

-        /* XXX */

-        break;

-    }

     return CKR_OK;

 }

+#else

+

+/* Declare const pointers since the old API gives us aliases. */

+#define DECLARE_BIGNUM(name) const BIGNUM *name

+#define RELEASE_BIGNUM(bn)

+static CK_RV

+get_bignums(EVP_PKEY *key, const BIGNUM **n, const BIGNUM **e)

+{

+    const RSA *rsa;

+

+    rsa = EVP_PKEY_get0_RSA(key);

+    RSA_get0_key(rsa, n, e, NULL);

+

+    return CKR_OK;

+}

+

+#endif

+

+static CK_RV

+add_pubkey_info(struct st_object *o, CK_KEY_TYPE key_type, EVP_PKEY *key)

+{

+    CK_BYTE *modulus = NULL, *exponent = 0;

+    size_t modulus_len = 0, exponent_len = 0;

+    CK_ULONG modulus_bits = 0;

+    CK_RV ret;

+    DECLARE_BIGNUM(n);

+    DECLARE_BIGNUM(e);

+

+    if (key_type != CKK_RSA)

+        abort();

+

+    ret = get_bignums(key, &n, &e);

+    if (ret != CKR_OK)

+        goto done;

+

+    modulus_bits = BN_num_bits(n);

+    modulus_len = BN_num_bytes(n);

+    exponent_len = BN_num_bytes(e);

+

+    modulus = malloc(modulus_len);

+    exponent = malloc(exponent_len);

+    if (modulus == NULL || exponent == NULL) {

+        ret = CKR_DEVICE_MEMORY;

+        goto done;

+    }

+

+    BN_bn2bin(n, modulus);

+    BN_bn2bin(e, exponent);

+

+    add_object_attribute(o, 0, CKA_MODULUS, modulus, modulus_len);

+    add_object_attribute(o, 0, CKA_MODULUS_BITS, &modulus_bits,

+                         sizeof(modulus_bits));

+    add_object_attribute(o, 0, CKA_PUBLIC_EXPONENT, exponent, exponent_len);

+

+    ret = CKR_OK;

+done:

+    free(modulus);

+    free(exponent);

+    RELEASE_BIGNUM(n);

+    RELEASE_BIGNUM(e);

+    return ret;

+}

 static int

 pem_callback(char *buf, int num, int w, void *key)