From c165523eab79be9a9d69f7abf77fc479720777b2 Mon Sep 17 00:00:00 2001
From: Cameron Pickett <pickett@meta.com>
Date: Wed, 28 Aug 2024 11:18:04 -0700
Subject: [PATCH] Upgrade base64 to 0.21 (#123)

Summary: Pull Request resolved: https://github.com/facebookresearch/Private-ID/pull/123

Reviewed By: zertosh

Differential Revision: D61737689

fbshipit-source-id: dc98887dd6b346f11d8efe7ffa085311f6110c37
---
 antlir/antlir2/features/install/install.rs          | 13 ++++++++++++-
 .../testing/image_diff_test/src/file_entry.rs       | 13 ++++++++++++-
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/antlir/antlir2/features/install/install.rs b/antlir/antlir2/features/install/install.rs
index 71101abd3f3..f87b7854336 100644
--- a/antlir/antlir2/features/install/install.rs
+++ b/antlir/antlir2/features/install/install.rs
@@ -30,6 +30,11 @@ use antlir2_users::GroupId;
 use antlir2_users::Id;
 use antlir2_users::UserId;
 use anyhow::Context;
+use base64::alphabet::STANDARD;
+use base64::engine::general_purpose::GeneralPurpose;
+use base64::engine::general_purpose::GeneralPurposeConfig;
+use base64::engine::DecodePaddingMode;
+use base64::Engine;
 #[cfg(feature = "setcap")]
 use libcap::Capabilities;
 #[cfg(feature = "setcap")]
@@ -44,6 +49,12 @@ use tracing::debug;
 use walkdir::WalkDir;
 use xattr::FileExt as _;
 
+// Bring back the pre 0.20 bevahiour and allow either padded or un-padded base64 strings at decode time.
+const STANDARD_INDIFFERENT: GeneralPurpose = GeneralPurpose::new(
+    &STANDARD,
+    GeneralPurposeConfig::new().with_decode_padding_mode(DecodePaddingMode::Indifferent),
+);
+
 pub type Feature = Install;
 
 #[serde_as]
@@ -181,7 +192,7 @@ impl<'de> Deserialize<'de> for XattrValue {
             let bytes = hex::decode(hex_value).map_err(D::Error::custom)?;
             Ok(Self(bytes))
         } else if let Some(b64) = s.strip_prefix("0s") {
-            let bytes = base64::decode(b64).map_err(D::Error::custom)?;
+            let bytes = STANDARD_INDIFFERENT.decode(b64).map_err(D::Error::custom)?;
             Ok(Self(bytes))
         } else {
             Ok(Self(s.into_bytes()))
diff --git a/antlir/antlir2/testing/image_diff_test/src/file_entry.rs b/antlir/antlir2/testing/image_diff_test/src/file_entry.rs
index e593e038c4c..f398f6bead9 100644
--- a/antlir/antlir2/testing/image_diff_test/src/file_entry.rs
+++ b/antlir/antlir2/testing/image_diff_test/src/file_entry.rs
@@ -19,6 +19,11 @@ use antlir2_facts::fact::user::User;
 use antlir2_mode::Mode;
 use anyhow::Context;
 use anyhow::Result;
+use base64::alphabet::STANDARD;
+use base64::engine::general_purpose::GeneralPurpose;
+use base64::engine::general_purpose::GeneralPurposeConfig;
+use base64::engine::DecodePaddingMode;
+use base64::Engine;
 use md5::Digest;
 use md5::Md5;
 use serde::de::Error as _;
@@ -27,6 +32,12 @@ use serde::Serialize;
 use serde_with::serde_as;
 use serde_with::DisplayFromStr;
 
+// Bring back the pre 0.20 bevahiour and allow either padded or un-padded base64 strings at decode time.
+const STANDARD_INDIFFERENT: GeneralPurpose = GeneralPurpose::new(
+    &STANDARD,
+    GeneralPurposeConfig::new().with_decode_padding_mode(DecodePaddingMode::Indifferent),
+);
+
 #[serde_as]
 #[serde_with::skip_serializing_none]
 #[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
@@ -232,7 +243,7 @@ impl<'de> Deserialize<'de> for XattrData {
             let bytes = hex::decode(hex_value).map_err(D::Error::custom)?;
             Ok(Self(bytes))
         } else if let Some(b64) = s.strip_prefix("0s") {
-            let bytes = base64::decode(b64).map_err(D::Error::custom)?;
+            let bytes = STANDARD_INDIFFERENT.decode(b64).map_err(D::Error::custom)?;
             Ok(Self(bytes))
         } else {
             Ok(Self(s.into_bytes()))