net/mptcp/crypto.c
Source file repositories/reference/linux-study-clean/net/mptcp/crypto.c
File Facts
- System
- Linux kernel
- Corpus path
net/mptcp/crypto.c- Extension
.c- Size
- 1700 bytes
- Lines
- 53
- Domain
- Networking Core
- Bucket
- Sockets, Protocols, Packet Path, And Network Policy
- Inferred role
- Networking Core: exported/initcall integration point
- Status
- integration implementation candidate
Why This File Exists
Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
- Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
- Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
Dependency Surface
linux/kernel.hcrypto/sha2.hprotocol.h
Detected Declarations
function Copyrightfunction mptcp_crypto_hmac_shaexport mptcp_crypto_hmac_sha
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP cryptographic functions
* Copyright (c) 2017 - 2019, Intel Corporation.
*
* Note: This code is based on mptcp_ctrl.c, mptcp_ipv4.c, and
* mptcp_ipv6 from multipath-tcp.org, authored by:
*
* Sébastien Barré <sebastien.barre@uclouvain.be>
* Christoph Paasch <christoph.paasch@uclouvain.be>
* Jaakko Korkeaniemi <jaakko.korkeaniemi@aalto.fi>
* Gregory Detal <gregory.detal@uclouvain.be>
* Fabien Duchêne <fabien.duchene@uclouvain.be>
* Andreas Seelinger <Andreas.Seelinger@rwth-aachen.de>
* Lavkesh Lahngir <lavkesh51@gmail.com>
* Andreas Ripke <ripke@neclab.eu>
* Vlad Dogaru <vlad.dogaru@intel.com>
* Octavian Purdila <octavian.purdila@intel.com>
* John Ronan <jronan@tssg.org>
* Catalin Nicutar <catalin.nicutar@gmail.com>
* Brandon Heller <brandonh@stanford.edu>
*/
#include <linux/kernel.h>
#include <crypto/sha2.h>
#include "protocol.h"
#define SHA256_DIGEST_WORDS (SHA256_DIGEST_SIZE / 4)
void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn)
{
__be32 mptcp_hashed_key[SHA256_DIGEST_WORDS];
__be64 input = cpu_to_be64(key);
sha256((__force u8 *)&input, sizeof(input), (u8 *)mptcp_hashed_key);
if (token)
*token = be32_to_cpu(mptcp_hashed_key[0]);
if (idsn)
*idsn = be64_to_cpu(*((__be64 *)&mptcp_hashed_key[6]));
}
void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac)
{
__be64 key[2] = { cpu_to_be64(key1), cpu_to_be64(key2) };
hmac_sha256_usingrawkey((const u8 *)key, sizeof(key), msg, len, hmac);
}
#if IS_MODULE(CONFIG_MPTCP_KUNIT_TEST)
EXPORT_SYMBOL_GPL(mptcp_crypto_hmac_sha);
#endif
Annotation
- Immediate include surface: `linux/kernel.h`, `crypto/sha2.h`, `protocol.h`.
- Detected declarations: `function Copyright`, `function mptcp_crypto_hmac_sha`, `export mptcp_crypto_hmac_sha`.
- Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
- Implementation status: integration implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.