cl_get_lock3

Usage

#include <libcanlock-3/canlock.h>

char *cl_get_lock(cl_hash_version hash,
                  const unsigned char *sec, size_t sec_len,
                  const unsigned char *msg, size_t msg_len);

Overview

The cl_get_lock() function creates a <c-lock> element according to the algorithm recommended by RFC 8315 in Section 4. The hash algorithm selected for <scheme> is used for the HMAC operation too.

The hash algorithm for <scheme> is selected with hash.

The local secret is specified with sec (sec_len must be set to the length of sec).
The length of the local secret should be at least the length of the hash that was selected for <scheme> (32 octets for SHA256).

The Message-ID of the target article (the one for which the lock is intended) is specified with msg (msg_len must be set to the length of msg).

The Message-ID msg can be prepended with an optional User-ID. The length of the User-ID must be added to msg_len. The User-ID must not contain angle brackets.

Return value

Upon successful completion a pointer to the result string is returned. Otherwise, NULL is returned.

On success the caller is responsible to call free() for the pointer returned as result.