Fix unit tests for NEO: use ECCP256 and detect attestation errors

lib/tests/api.c

@@ -409,8 +409,15 @@ START_TEST(test_import_key) {
   {
     unsigned char attest[2048];
     size_t attest_len = sizeof(attest);
+    ykpiv_devmodel model;
+    model = ykpiv_util_devicemodel(g_state);
     res = ykpiv_attest(g_state, 0x9e, attest, &attest_len);
-    ck_assert_int_eq(res, YKPIV_GENERIC_ERROR);
+    if (model == DEVTYPE_YK4) {
+      ck_assert_int_eq(res, YKPIV_GENERIC_ERROR);
+    }
+    else {
+      ck_assert_int_eq(res, YKPIV_NOT_SUPPORTED);
+    }
   }
 }
 END_TEST
@@ -440,11 +447,19 @@ START_TEST(test_generate_key) {
 
   // Verify that imported key can be attested
   {
+    ykpiv_devmodel model;
     unsigned char attest[2048];
     size_t attest_len = sizeof(attest);
+    model = ykpiv_util_devicemodel(g_state);
     res = ykpiv_attest(g_state, YKPIV_KEY_AUTHENTICATION, attest, &attest_len);
-    ck_assert_int_eq(res, YKPIV_OK);
-    ck_assert_int_gt(attest_len, 0);
+    // Only works with YK4.  NEO should error.
+    if (model == DEVTYPE_YK4) {
+      ck_assert_int_eq(res, YKPIV_OK);
+      ck_assert_int_gt(attest_len, 0);
+    }
+    else {
+      ck_assert_int_eq(res, YKPIV_NOT_SUPPORTED);
+    }
   }
 }
 END_TEST

lib/ykpiv.c

@@ -1346,6 +1346,9 @@ ykpiv_rc ykpiv_attest(ykpiv_state *state, const unsigned char key, unsigned char
     return res;
   }
   else if(SW_SUCCESS != sw) {
+    if (sw == SW_ERR_NOT_SUPPORTED) {
+      return YKPIV_NOT_SUPPORTED;
+    }
     return YKPIV_GENERIC_ERROR;
   }
   if (data[0] != 0x30) {

lib/ykpiv.h

@@ -61,7 +61,8 @@ extern "C"
     YKPIV_PIN_LOCKED = -13,
 
     YKPIV_ARGUMENT_ERROR = -14, //i.e. invalid input argument
-    YKPIV_RANGE_ERROR = -15 //i.e. value range error
+    YKPIV_RANGE_ERROR = -15, //i.e. value range error
+    YKPIV_NOT_SUPPORTED = -16
   } ykpiv_rc;
 
   typedef void* (*ykpiv_pfn_alloc)(void* alloc_data, size_t size);
@@ -217,6 +218,7 @@ extern "C"
 #define SW_ERR_INCORRECT_PARAM 0x6a80
 /* this is a custom sw for yubikey */
 #define SW_ERR_INCORRECT_SLOT 0x6b00
+#define SW_ERR_NOT_SUPPORTED 0x6d00
 
   /* Yubico vendor specific instructions */
 #define YKPIV_INS_SET_MGMKEY 0xff