Added test case with low-level botan calls, reproducing windows crash…

… issue.

src/tests/cipher.cpp

@@ -1137,3 +1137,79 @@ TEST_F(rnp_tests, test_brainpool_enabled)
     assert_false(supported);
 #endif
 }
+
+#if defined(CRYPTO_BACKEND_BOTAN)
+TEST_F(rnp_tests, test_windows_botan_crash)
+{
+    /* Reproducer for https://github.com/randombit/botan/issues/3812 . Related CLI test test
+     * test_sym_encrypted__rnp_aead_botan_crash */
+    /* First 32 bytes are encrypted key as it was extracted from the OpenPGP stream. */
+
+    auto    data = file_to_vec("data/test_messages/message.aead-windows-issue-botan");
+    size_t  idx = 32;
+    uint8_t bufbin[64] = {0};
+    uint8_t outbuf[32768] = {0};
+    size_t  written = 0;
+    size_t  read = 0;
+    size_t  diff = 0;
+
+    /* Now the data which exposes a possible crash */
+    struct botan_cipher_struct *cipher = NULL;
+    assert_int_equal(botan_cipher_init(&cipher, "AES-128/OCB", BOTAN_CIPHER_INIT_FLAG_DECRYPT),
+                     0);
+
+    const char *key2 = "417835a476bc5958b18d41fb00cf682d";
+    assert_int_equal(rnp::hex_decode(key2, bufbin, 16), 16);
+    assert_int_equal(botan_cipher_set_key(cipher, bufbin, 16), 0);
+
+    const char *ad2 = "d40107020c0000000000000000";
+    assert_int_equal(rnp::hex_decode(ad2, bufbin, 13), 13);
+    assert_int_equal(botan_cipher_set_associated_data(cipher, bufbin, 13), 0);
+
+    const char *nonce2 = "005dbbbe0088f9d17ca2d8d464920f";
+    assert_int_equal(rnp::hex_decode(nonce2, bufbin, 15), 15);
+    assert_int_equal(botan_cipher_start(cipher, bufbin, 15), 0);
+
+    assert_int_equal(
+      botan_cipher_update(
+        cipher, 0, outbuf, sizeof(outbuf), &written, data.data() + idx, 32736, &read),
+      0);
+    diff = 32736 - read;
+    idx += read;
+
+    assert_int_equal(
+      botan_cipher_update(
+        cipher, 0, outbuf, sizeof(outbuf), &written, data.data() + idx, diff + 32736, &read),
+      0);
+    idx += read;
+    diff = diff + 32736 - read;
+
+    assert_int_equal(
+      botan_cipher_update(
+        cipher, 0, outbuf, sizeof(outbuf), &written, data.data() + idx, diff + 32736, &read),
+      0);
+    idx += read;
+    diff = diff + 32736 - read;
+
+    assert_int_equal(
+      botan_cipher_update(
+        cipher, 0, outbuf, sizeof(outbuf), &written, data.data() + idx, diff + 32736, &read),
+      0);
+    idx += read;
+    diff = diff + 32736 - read;
+
+    assert_int_equal(botan_cipher_update(cipher,
+                                         BOTAN_CIPHER_UPDATE_FLAG_FINAL,
+                                         outbuf,
+                                         sizeof(outbuf),
+                                         &written,
+                                         data.data() + idx,
+                                         diff + 25119,
+                                         &read),
+                     0);
+    idx += read;
+
+    assert_int_equal(botan_cipher_reset(cipher), 0);
+    assert_int_equal(botan_cipher_destroy(cipher), 0);
+}
+#endif