java.lang.IllegalStateException: Arithmetic error in curve multiplication with the public key

[dmpatel151282]

We are using Tink-Android 1.4 version of library in Android project.

Here are the device details.

Android version: 7.0 cpu: MediaTek MT6737 gpu: ARM Mali-T720 Tink-Android Version: 1.4.0

We are facing above issue in this Android device only.

Stack trace: W/System.err: java.lang.IllegalStateException: Arithmetic error in curve multiplication with the public key: e9613cc69b61dc962fd0ab7ef185fd94e7e278d0775a2ac5df93dba804474c0d W/System.err: at com.google.crypto.tink.subtle.Curve25519.curveMult(Curve25519.java:332) W/System.err: at com.google.crypto.tink.subtle.X25519.computeSharedSecret(X25519.java:103)

Please help us to solve it.

[thaidn]

Thanks for the report. Is it possible to share the private key? We need both parameters of com.google.crypto.tink.subtle.X25519.computeSharedSecret.

[dmpatel151282]

Sorry for late reply.

Here are both parameters.

privateKey byte[]: [-41, 31, -70, 113, 57, -124, 109, 102, 91, 50, 64, 33, 43, -82, 124, -48, -74, -92, -92, 45, -16, -2, 43, -77, -116, -16, -18, 86, 18, 20, 41, -124] privateKey Hex: D71FBA7139846D665B3240212BAE7CD0B6A4A42DF0FE2BB38CF0EE5612142984

publicKey byte[]: [-40, -16, 59, -76, -92, 23, -22, -84, -108, -122, 57, -80, 66, 26, 52, -86, -83, -33, 9, 5, 115, -47, 33, 30, 27, 126, 39, 27, 67, -51, -96, 92] publicKey Hex: D8F03BB4A417EAAC948639B0421A34AAADDF090573D1211E1B7E271B43CDA05C

[dmpatel151282]

Any update???

[sophieschmieg]

We've been trying to reproduce it, but without any luck so far.

[thaidn]

@dmpatel151282 did you encounter this failure on an ASUS ZenFone 3 MAX (ZC520TL) running Android 7.0 Nougat? Another user reported the same failure on this phone, which has the same CPU and GPU as your phone. They wrote:

I've narrowed down the issue to the execution of the following function, on line 294, when i == 3 && j == 7: monty(nqx2, nqz2, nqpqx2, nqpqz2, nqx, nqz, nqpqx, nqpqz, q);

Can you confirm that on your phone it also happens on line 294 when i == 3 and j == 7?

[thaidn]

I've bought an ASUS phone running MediaTek and will have it in a week. Will update once I've got more information.

[dmpatel151282]

Thanks for support. I will also try above from my side and will let you know result.

[xDragonZ]

Here's more devices having this issue Android OS: 7.0, 7.1.1 Tink: 1.5.0 (tink / tink-android)

---

Device:

Oppo: CPH1723, CPH1729, CPH1717 Sony: Xperia L1 CMDC: M760 Infinix HOT 4 Pro Meizu: M6

---

setF(byte[] f)

clientPrivate: 872c537cad16b802261c81d34f32eceebbecd14d2789ca38701031bc415f0787
serverPublic: 3b7baf9c70df06b0a8b4aadbb96b08e8c1455b16fbd44cb7656d2a183369ff64

[np16474]

i'm getting a similar issue as well: java.lang.IllegalStateException: Arithmetic error in curve multiplication with the public key: 0900000000000000000000000000000000000000000000000000000000000000 the device was: OS Version: Android SDK: 25 (7.1.1) Phone model: OPPO CPH1725

[Tougee]

Same here, all Android SDK versions are 25(7.1.1)

[ToddChang]

same here with oppo cph1723 (android 7.1.1 + mediatek cpu)

[tholenst]

I will close this.

From our understanding this could be a hardware issue on very few devices. If this is the case, I would expect it only to happen very infrequently and only in some devices.

If this is not the case, and someone can observe this frequently or can reproduce it, please open an issue on github.com/tink-crypto/tink-java/ where Tink Java now lives.