Struct EncryptedRangePlan 

pub struct EncryptedRangePlan {
    pub chunk_idx_start: u32,
    pub chunk_idx_last_inclusive: u32,
    pub enc_byte_start: u64,
    pub enc_byte_end_exclusive: u64,
    pub pre_encrypt_slice_start_in_concat: u64,
    pub pre_encrypt_slice_end_in_concat: u64,
}

v0.9 #106: encrypted partial-fetch plan for the SSE-S4 chunked (S4E6) Range GET fast-path. Given a RangePlan (which describes the pre-encrypt byte range to fetch) plus the per-object SSE binding, computes the actual encrypted byte range to send the backend, the S4E6 chunk index range to walk, and where the pre-encrypt byte range lands inside the decrypted chunk concatenation.

Caller workflow:

1. backend partial GET body[enc_byte_start..enc_byte_end_exclusive) plus the S4E6 fixed header (already cached in the sidecar’s SseChunkBinding, no extra fetch).
2. for chunk_idx in chunk_idx_start..=chunk_idx_last_inclusive, decrypt_chunk(chunk_idx, &body[..]) — the sidecar’s salt + key_id provide the AAD / nonce material.
3. concatenate the decrypted plaintext, slice off pre_encrypt_slice_start_in_concat..pre_encrypt_slice_end_in_concat to land at the RangePlan’s byte_start..byte_end_exclusive (= pre-encrypt) range.
4. frame-parse + decompress + final slice via the existing RangePlan machinery.

Fields

chunk_idx_start: u32

First S4E6 chunk that overlaps the requested pre-encrypt range (inclusive).

chunk_idx_last_inclusive: u32

Last S4E6 chunk that overlaps the requested pre-encrypt range (inclusive).

enc_byte_start: u64

Byte offset within the encrypted backend body where the fetch starts (covers chunk chunk_idx_start’s tag + ciphertext).

enc_byte_end_exclusive: u64

Byte offset (exclusive) within the encrypted backend body where the fetch ends (covers through chunk chunk_idx_last_inclusive).

pre_encrypt_slice_start_in_concat: u64

Offset within the decrypted-chunk concatenation where the pre-encrypt slice starts (= RangePlan.byte_start - chunk_idx_start * enc_chunk_size).

pre_encrypt_slice_end_in_concat: u64

Offset within the decrypted-chunk concatenation where the pre-encrypt slice ends (exclusive).

Trait Implementations

impl Clone for EncryptedRangePlan

fn clone(&self) -> EncryptedRangePlan

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for EncryptedRangePlan

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for EncryptedRangePlan

impl PartialEq for EncryptedRangePlan

fn eq(&self, other: &EncryptedRangePlan) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for EncryptedRangePlan