Use the base64 encoding/decoding methods from vodozemac in the bindings

Cargo.lock

@@ -3195,7 +3195,6 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "assert_matches",
- "base64 0.21.2",
  "futures-util",
  "hmac",
  "http",

bindings/matrix-sdk-crypto-ffi/Cargo.toml

@@ -18,7 +18,6 @@ bundled-sqlite = ["matrix-sdk-sqlite/bundled"]
 
 [dependencies]
 anyhow = { workspace = true }
-base64 = { workspace = true }
 futures-util = "0.3.25"
 hmac = "0.12.1"
 http = { workspace = true }

bindings/matrix-sdk-crypto-ffi/src/verification.rs

@@ -1,10 +1,5 @@
 use std::sync::Arc;
 
-use base64::{
-    alphabet,
-    engine::{general_purpose, GeneralPurpose},
-    Engine,
-};
 use futures_util::{Stream, StreamExt};
 use matrix_sdk_crypto::{
     matrix_sdk_qrcode::QrVerificationData, CancelInfo as RustCancelInfo, QrVerification as InnerQr,
@@ -14,12 +9,10 @@ use matrix_sdk_crypto::{
 };
 use ruma::events::key::verification::VerificationMethod;
 use tokio::runtime::Handle;
+use vodozemac::{base64_decode, base64_encode};
 
 use crate::{CryptoStoreError, OutgoingVerificationRequest, SignatureUploadRequest};
 
-const STANDARD_NO_PAD: GeneralPurpose =
-    GeneralPurpose::new(&alphabet::STANDARD, general_purpose::NO_PAD);
-
 /// Listener that will be passed over the FFI to report changes to a SAS
 /// verification.
 #[uniffi::export(callback_interface)]
@@ -420,7 +413,7 @@ impl QrCode {
     /// decoded on the other side before it can be put through a QR code
     /// generator.
     pub fn generate_qr_code(&self) -> Option<String> {
-        self.inner.to_bytes().map(|data| STANDARD_NO_PAD.encode(data)).ok()
+        self.inner.to_bytes().map(base64_encode).ok()
     }
 
     /// Set a listener for changes in the QrCode verification process.
@@ -713,7 +706,7 @@ impl VerificationRequest {
     /// * `data` - The data that was extracted from the scanned QR code as an
     /// base64 encoded string, without padding.
     pub fn scan_qr_code(&self, data: String) -> Option<ScanResult> {
-        let data = STANDARD_NO_PAD.decode(data).ok()?;
+        let data = base64_decode(data).ok()?;
         let data = QrVerificationData::from_bytes(data).ok()?;
 
         if let Some(qr) = self.runtime.block_on(self.inner.scan_qr_code(data)).ok()? {