feat(quartz): NIP-BC sign_psbt over NIP-55 external signer (Phase B)

Wires the NIP-55 Android external-signer contract for sign_psbt, so NostrSignerExternal.signPsbt is real instead of a stub. - CommandType.SIGN_PSBT ("sign_psbt") — also available in NIP-55 `perms` lists, since Permission wraps CommandType directly. - SignPsbtResult result type. - SignPsbtQuery (background ContentResolver) + SignPsbtRequest / SignPsbtResponse (foreground Intent), modeled on the derive_key string-in/string-out shape: the PSBT hex rides the `nostrsigner:` URI, the signed (not finalized) PSBT comes back in the `result` field. - BackgroundRequestHandler.signPsbt / ForegroundRequestHandler.signPsbt. - NostrSignerExternal.signPsbt now runs the background-then-foreground query. Signer apps that predate sign_psbt reply with no `result`, which surfaces as CouldNotPerformException — the send dialog shows it as a failure ("update your signer"). NIP-46 (NostrSignerRemote) still throws UnsupportedMethodException — the bunker-side command isn't standardized yet.
2026-05-14 12:50:47 +00:00
parent bb0f41d320
commit 5f16ebc060
9 changed files with 211 additions and 15 deletions
@@ -31,6 +31,7 @@ enum class CommandType(
    GET_PUBLIC_KEY("get_public_key"),
    DECRYPT_ZAP_EVENT("decrypt_zap_event"),
    DERIVE_KEY("derive_key"),
+    SIGN_PSBT("sign_psbt"),
    ;

    companion object {
@@ -44,6 +45,7 @@ enum class CommandType(
                GET_PUBLIC_KEY.code -> GET_PUBLIC_KEY
                DECRYPT_ZAP_EVENT.code -> DECRYPT_ZAP_EVENT
                DERIVE_KEY.code -> DERIVE_KEY
+                SIGN_PSBT.code -> SIGN_PSBT
                else -> null
            }
    }
@@ -89,3 +89,7 @@ data class ZapEventDecryptionResult(
 data class DerivationResult(
    val newPrivKey: HexKey,
 ) : IResult
+
+data class SignPsbtResult(
+    val signedPsbtHex: String,
+) : IResult
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries
+
+import android.content.ContentResolver
+import androidx.core.net.toUri
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.CommandType
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignPsbtResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignerResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.utils.getStringByName
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.utils.query
+
+/**
+ * NIP-BC `sign_psbt` background (ContentResolver) query.
+ *
+ * Passes the unsigned/partially-signed PSBT (lowercase hex) to the external
+ * signer app and expects the updated PSBT back in the `result` column. The
+ * signer signs each input whose `tapInternalKey` matches the user's pubkey;
+ * it does NOT finalize the PSBT.
+ */
+class SignPsbtQuery(
+    val loggedInUser: HexKey,
+    val packageName: String,
+    val contentResolver: ContentResolver,
+) {
+    val uri = "content://$packageName.${CommandType.SIGN_PSBT}".toUri()
+
+    fun query(psbtHex: String): SignerResult<SignPsbtResult> =
+        contentResolver.query(
+            uri,
+            arrayOf(psbtHex, loggedInUser),
+        ) { cursor ->
+            val signedPsbtHex = cursor.getStringByName("result")
+            if (!signedPsbtHex.isNullOrBlank()) {
+                SignerResult.RequestAddressed.Successful(SignPsbtResult(signedPsbtHex))
+            } else {
+                SignerResult.RequestAddressed.ReceivedButCouldNotPerform()
+            }
+        }
+}
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests
+
+import android.content.Intent
+import androidx.core.net.toUri
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.CommandType
+
+/**
+ * NIP-BC `sign_psbt` foreground Intent request.
+ *
+ * Carries the PSBT (lowercase hex) as the `nostrsigner:` URI data so the
+ * signer app can display the inputs/outputs to the user for confirmation.
+ */
+class SignPsbtRequest {
+    companion object {
+        fun assemble(
+            psbtHex: String,
+            loggedInUser: HexKey,
+            packageName: String,
+        ): Intent {
+            val intent = Intent(Intent.ACTION_VIEW, "nostrsigner:$psbtHex".toUri())
+            intent.`package` = packageName
+            intent.putExtra("type", CommandType.SIGN_PSBT.code)
+            intent.putExtra("current_user", loggedInUser)
+            return intent
+        }
+    }
+}
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses
+
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignPsbtResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignerResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.results.IntentResult
+
+/**
+ * Parses the external signer's `sign_psbt` Intent reply. The `result` field
+ * carries the updated (signed, not finalized) PSBT as lowercase hex.
+ */
+class SignPsbtResponse {
+    companion object {
+        fun assemble(signedPsbtHex: String): IntentResult =
+            IntentResult(
+                result = signedPsbtHex,
+            )
+
+        fun parse(intent: IntentResult): SignerResult.RequestAddressed<SignPsbtResult> {
+            if (intent.rejected == true) {
+                return SignerResult.RequestAddressed.ManuallyRejected()
+            }
+            val signedPsbtHex = intent.result
+            return if (!signedPsbtHex.isNullOrBlank()) {
+                SignerResult.RequestAddressed.Successful(SignPsbtResult(signedPsbtHex))
+            } else {
+                SignerResult.RequestAddressed.ReceivedButCouldNotPerform()
+            }
+        }
+    }
+}
@@ -30,6 +30,7 @@ import com.vitorpamplona.quartz.nip01Core.signers.SignerExceptions
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.DecryptionResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.DerivationResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.EncryptionResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignPsbtResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignerResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.ZapEventDecryptionResult
@@ -175,16 +176,23 @@ class NostrSignerExternal(
    }

    /**
-     * NIP-BC `sign_psbt` over NIP-55. The Android external-signer Intent
-     * contract for PSBT signing is not implemented yet (Phase B); Amber and
-     * other signer apps must also ship support before this can work. Until
-     * then, callers should fall back to other signer kinds or surface an
-     * "update your signer" message.
+     * NIP-BC `sign_psbt` over NIP-55. Sends the PSBT (lowercase hex) to the
+     * external signer app, which signs each input whose `tapInternalKey`
+     * matches the user's pubkey and returns the updated (not finalized) PSBT.
+     *
+     * Signer apps that predate `sign_psbt` support reply with no `result`,
+     * which surfaces here as [SignerExceptions.CouldNotPerformException] —
+     * callers should treat that as "update your signer".
     */
-    override suspend fun signPsbt(psbtHex: String): String =
-        throw SignerExceptions.UnsupportedMethodException(
-            "This external signer does not support sign_psbt yet",
-        )
+    override suspend fun signPsbt(psbtHex: String): String {
+        val result = backgroundQuery.signPsbt(psbtHex) ?: foregroundQuery.signPsbt(psbtHex)
+
+        if (result is SignerResult.RequestAddressed.Successful<SignPsbtResult>) {
+            return result.result.signedPsbtHex
+        }
+
+        throw convertExceptions("Could not sign PSBT", result)
+    }

    // always ready
    override fun hasForegroundSupport() = hasForegroundActivity()
@@ -27,6 +27,7 @@ import com.vitorpamplona.quartz.nip55AndroidSigner.api.DecryptionResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.DerivationResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.EncryptionResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.PubKeyResult
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignPsbtResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.SignerResult
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.ZapEventDecryptionResult
@@ -37,6 +38,7 @@ import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.Nip04D
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.Nip04EncryptQuery
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.Nip44DecryptQuery
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.Nip44EncryptQuery
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.SignPsbtQuery
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.background.queries.SignQuery
 import com.vitorpamplona.quartz.nip57Zaps.LnZapRequestEvent

@@ -53,6 +55,7 @@ class BackgroundRequestHandler(
    val nip44Decrypt = Nip44DecryptQuery(loggedInUser, packageName, contentResolver)
    val decryptZap = DecryptZapQuery(loggedInUser, packageName, contentResolver)
    val deriveKey = DeriveKeyQuery(loggedInUser, packageName, contentResolver)
+    val signPsbt = SignPsbtQuery(loggedInUser, packageName, contentResolver)

    fun login() = login.query() as? SignerResult.RequestAddressed<PubKeyResult>

@@ -81,4 +84,6 @@ class BackgroundRequestHandler(
    fun decryptZapEvent(event: LnZapRequestEvent) = decryptZap.query(event) as? SignerResult.RequestAddressed<ZapEventDecryptionResult>

    fun deriveKey(nonce: HexKey) = deriveKey.query(nonce) as? SignerResult.RequestAddressed<DerivationResult>
+
+    fun signPsbt(psbtHex: String) = signPsbt.query(psbtHex) as? SignerResult.RequestAddressed<SignPsbtResult>
 }
@@ -29,6 +29,7 @@ import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.reques
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests.Nip04EncryptRequest
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests.Nip44DecryptRequest
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests.Nip44EncryptRequest
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests.SignPsbtRequest
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.requests.SignRequest
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.DecryptZapResponse
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.DeriveKeyResponse
@@ -36,6 +37,7 @@ import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.respon
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.Nip04EncryptResponse
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.Nip44DecryptResponse
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.Nip44EncryptResponse
+import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.SignPsbtResponse
 import com.vitorpamplona.quartz.nip55AndroidSigner.api.foreground.intents.responses.SignResponse
 import com.vitorpamplona.quartz.nip57Zaps.LnZapRequestEvent

@@ -95,4 +97,10 @@ class ForegroundRequestHandler(
            requestIntentBuilder = { DeriveKeyRequest.assemble(nonce, loggedInUser, packageName) },
            parser = DeriveKeyResponse::parse,
        )
+
+    suspend fun signPsbt(psbtHex: String) =
+        launcher.launchWaitAndParse(
+            requestIntentBuilder = { SignPsbtRequest.assemble(psbtHex, loggedInUser, packageName) },
+            parser = SignPsbtResponse::parse,
+        )
 }