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libfreemkv 0.31.4: prune 144 vacuous tests (keep spec-grounded subset)

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Matthew Jackson
2026-06-08 07:28:55 -07:00
parent d181362460
commit f79c2a0aa9
51 changed files with 7 additions and 2142 deletions
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src/css/tables.rs
-38
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@@ -143,25 +143,6 @@ mod tests {
}
}
/// All five tables have exactly the lengths the CSS cipher requires.
/// TAB3 is 9-bit-indexed (the LFSR1 low word carries a 9th bit), hence
/// 512 entries; every other table is byte-indexed (256). A truncated or
/// padded table would index out of bounds or read stale data inside the
/// LFSR loops.
///
/// Grounding: lfsr.rs indexes TAB3 with `*lfsr1_lo as usize` where
/// `lfsr1_lo` can be up to 0x1FF (9 bits), so TAB3 MUST be >= 512 long.
/// Mutation: change `[u8; 512]` to `[u8; 256]` (drop the second half) ->
/// fails to compile / length assert fails.
#[test]
fn table_lengths_match_css_index_widths() {
assert_eq!(TAB1.len(), 256, "TAB1 is byte-indexed");
assert_eq!(TAB2.len(), 256, "TAB2 is byte-indexed");
assert_eq!(TAB3.len(), 512, "TAB3 is 9-bit-indexed (LFSR1 low word)");
assert_eq!(TAB4.len(), 256, "TAB4 is byte-indexed");
assert_eq!(TAB5.len(), 256, "TAB5 is byte-indexed");
}
/// TAB1 is a bijection on 0..256. CSS uses it as an invertible output
/// permutation in css_DecryptKey's chained-XOR rounds; if two inputs
/// collided, the key mangling would not be invertible.
@@ -234,25 +215,6 @@ mod tests {
}
}
/// TAB3's value depends only on the bottom 3 bits and the top group:
/// within a 128-entry block (constant i>>7) every 8-aligned run repeats.
/// Specifically TAB3[i] == TAB3[i & 0x187] (mask keeping bits 0..2 and
/// bits 7..8). This is the structural redundancy the generating formula
/// implies and a different cross-check on the same data.
///
/// Mutation: change TAB3[16] (currently a repeat of TAB3[0]=0x00) to
/// 0x24 -> the repeat check fails.
#[test]
fn tab3_repeats_within_block() {
for (i, &v) in TAB3.iter().enumerate() {
let canonical = (i & 0b1_1000_0111) & 0x1FF;
assert_eq!(
v, TAB3[canonical],
"TAB3[{i:#05x}] should repeat TAB3[{canonical:#05x}]"
);
}
}
/// TAB4 is the exact bit-reversal of each byte (CSS uses it to permute
/// LFSR0 bytes on seed and output). TAB4[b] reverses b's 8 bits MSB<->LSB.
/// Therefore it is also an involution: TAB4[TAB4[b]] == b.