Momoko-Ayase/Senbei
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build: require Rust 1.98.1

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This commit is contained in:
bfloat16
2026-09-07 21:43:15 +08:00
parent 6250ca4e98
commit 53ef36c837
9 changed files with 28 additions and 39 deletions
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senbei-engine/src/android/extract/stage1.rs
+3 -7
View File
@@ -177,18 +177,14 @@ fn decrypt_header(raw: &[u8], constant: u32) -> Result<Stage1Header> {
}
fn decrypt_words(ciphertext: &[u8], key: u32, constant: u32) -> Result<Vec<u8>> {
if ciphertext.len() % 4 != 0 {
if !ciphertext.len().is_multiple_of(4) {
return invalid("Stage 1 word cipher input is not 4-byte aligned");
}
let mut plaintext = ciphertext.to_vec();
for (index, chunk) in plaintext.chunks_exact_mut(4).enumerate() {
for (index, chunk) in plaintext.as_chunks_mut::<4>().0.iter_mut().enumerate() {
let index = u32::try_from(index)
.map_err(|_| Error::Invalid("Stage 1 word index exceeds u32".to_owned()))?;
let mut word = u32::from_le_bytes(
chunk
.try_into()
.map_err(|_| Error::Invalid("Stage 1 word has an invalid size".to_owned()))?,
);
let mut word = u32::from_le_bytes(*chunk);
word = word.wrapping_add(index.wrapping_add(3).wrapping_mul(key));
word ^= constant.wrapping_mul(index.wrapping_add(1));
chunk.copy_from_slice(&word.to_le_bytes());
senbei-engine/src/android/extract/stream.rs
+2 -6
View File
@@ -130,13 +130,9 @@ fn decrypt_record(raw: &[u8], index: usize, state: u32) -> Result<Record> {
let mut accumulator = 0x7993_4cf6_u32;
let mut feedback = 0xf02f_7685_u32;
let mut words = [0_u32; RECORD_SIZE / 4];
for (word_index, chunk) in raw.chunks_exact(4).enumerate() {
for (word_index, chunk) in raw.as_chunks::<4>().0.iter().enumerate() {
feedback = feedback.wrapping_mul(feedback);
let cipher = u32::from_le_bytes(
chunk
.try_into()
.map_err(|_| Error::Invalid("record word has an invalid size".to_owned()))?,
);
let cipher = u32::from_le_bytes(*chunk);
let mut value = gf32_mul_fixed(cipher ^ (feedback >> 3)) ^ index_mask;
value = value.wrapping_add(accumulator).wrapping_add(state);
value = value.wrapping_sub(mix >> ((word_index * 4 + 3) & 5));