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//! `S3Service` `encryption` family — extracted from service.rs by audit-2026-05-19.
use super::*;
impl S3Service {
// ---- Encryption ----
pub(crate) fn put_bucket_encryption(
&self,
account_id: &str,
req: &AwsRequest,
bucket: &str,
) -> Result<AwsResponse, AwsServiceError> {
let body_str = std::str::from_utf8(&req.body).unwrap_or("").to_string();
// Validate the SSE config fields *before* persisting. The stored
// body is later round-tripped, field-by-field, into the object
// default-encryption headers on PutObject and ultimately into the
// `x-amz-server-side-encryption` / `-aws-kms-key-id` *response*
// headers on a later GET/HEAD. A control byte here (all bytes
// 0x00-0x1F are legal XML body bytes but illegal HTTP header bytes)
// would otherwise be persisted verbatim and crash the read path —
// a reachable, unauthenticated-input DoS (bug-audit 2026-06-13 2.1/2.2).
if let Some(algo) = extract_xml_value(&body_str, "SSEAlgorithm") {
// SSEAlgorithm is a closed enum; AWS returns MalformedXML for
// anything outside it.
if algo != "AES256" && algo != "aws:kms" && algo != "aws:kms:dsse" {
return Err(malformed_encryption("SSEAlgorithm", &algo));
}
}
if let Some(kid) = extract_xml_value(&body_str, "KMSMasterKeyID") {
// A real KMS key id / ARN / alias never contains control
// characters. Reject any value that isn't a legal HTTP header
// value rather than persisting a string that would later panic
// the GET/HEAD response path. AWS rejects a malformed key id with
// KMS.KMSInvalidStateException / InvalidArgument; InvalidArgument
// is the closest stable shape here.
if kid.parse::<http::header::HeaderValue>().is_err() {
return Err(AwsServiceError::aws_error_with_fields(
StatusCode::BAD_REQUEST,
"InvalidArgument",
"The KMSMasterKeyID is not a valid KMS key id, ARN, or alias",
vec![
("ArgumentName".to_string(), "KMSMasterKeyID".to_string()),
("ArgumentValue".to_string(), kid.clone()),
],
));
}
}
// aws:kms / aws:kms:dsse rules require KMSMasterKeyID — AWS
// rejects these with InvalidArgument when the field is
// missing or empty, since the bucket would otherwise have
// no key to encrypt against.
if (body_str.contains("aws:kms") || body_str.contains("aws:kms:dsse"))
&& !has_kms_master_key_id(&body_str)
{
return Err(AwsServiceError::aws_error(
StatusCode::BAD_REQUEST,
"InvalidArgument",
"Default KMS encryption requires KMSMasterKeyID",
));
}
let mut accts = self.state.write();
let state = accts.get_or_create(account_id);
let b = state
.buckets
.get_mut(bucket)
.ok_or_else(|| no_such_bucket(bucket))?;
// Normalize: add BucketKeyEnabled=false to each <Rule> that
// is missing one. The prior whole-body check skipped this when
// a different rule already had BucketKeyEnabled, so mixed
// configs would drop the default on rules that needed it.
let normalized = {
let mut out = String::with_capacity(body_str.len() + 64);
let mut cursor = 0usize;
while let Some(start) = body_str[cursor..].find("<Rule>") {
let abs_start = cursor + start;
out.push_str(&body_str[cursor..abs_start]);
let rule_open = abs_start;
let rest = &body_str[rule_open..];
if let Some(end_rel) = rest.find("</Rule>") {
let rule_block = &rest[..end_rel];
let mut rule_out = rule_block.to_string();
if !rule_block.contains("<BucketKeyEnabled>") {
rule_out.push_str("<BucketKeyEnabled>false</BucketKeyEnabled>");
}
rule_out.push_str("</Rule>");
out.push_str(&rule_out);
cursor = rule_open + end_rel + "</Rule>".len();
} else {
out.push_str(rest);
cursor = body_str.len();
break;
}
}
out.push_str(&body_str[cursor..]);
out
};
b.encryption_config = Some(normalized.clone());
self.store
.put_bucket_subresource(bucket, BucketSubresource::Encryption, &normalized)
.map_err(crate::service::persistence_error)?;
Ok(empty_response(StatusCode::OK))
}
pub(crate) fn get_bucket_encryption(
&self,
account_id: &str,
bucket: &str,
) -> Result<AwsResponse, AwsServiceError> {
let accts = self.state.read();
let __empty = crate::state::S3State::new(account_id, "us-east-1");
let state = accts.get(account_id).unwrap_or(&__empty);
let b = state
.buckets
.get(bucket)
.ok_or_else(|| no_such_bucket(bucket))?;
match &b.encryption_config {
Some(config) => Ok(s3_xml(StatusCode::OK, config.clone())),
None => Err(AwsServiceError::aws_error_with_fields(
StatusCode::NOT_FOUND,
"ServerSideEncryptionConfigurationNotFoundError",
"The server side encryption configuration was not found",
vec![("BucketName".to_string(), bucket.to_string())],
)),
}
}
pub(crate) fn delete_bucket_encryption(
&self,
account_id: &str,
bucket: &str,
) -> Result<AwsResponse, AwsServiceError> {
let mut accts = self.state.write();
let state = accts.get_or_create(account_id);
let b = state
.buckets
.get_mut(bucket)
.ok_or_else(|| no_such_bucket(bucket))?;
b.encryption_config = None;
self.store
.delete_bucket_subresource(bucket, BucketSubresource::Encryption)
.map_err(crate::service::persistence_error)?;
Ok(empty_response(StatusCode::NO_CONTENT))
}
}
/// Build a `MalformedXML` error for a bucket-encryption field whose value
/// isn't a member of its closed enum (e.g. an `SSEAlgorithm` other than
/// AES256/aws:kms/aws:kms:dsse). Matches AWS, which rejects such bodies with
/// 400 MalformedXML.
fn malformed_encryption(field: &str, value: &str) -> AwsServiceError {
AwsServiceError::aws_error_with_fields(
StatusCode::BAD_REQUEST,
"MalformedXML",
"The XML you provided was not well-formed or did not validate against \
our published schema",
vec![
("ArgumentName".to_string(), field.to_string()),
("ArgumentValue".to_string(), value.to_string()),
],
)
}