// SPDX-License-Identifier: GPL-2.0-or-later
/* AF_RXRPC local endpoint management
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <generated/utsrelease.h>
#include "ar-internal.h"

static char rxrpc_version_string[65]; // "linux-" UTS_RELEASE " AF_RXRPC";

/*
 * Generate the VERSION packet string.
 */
void rxrpc_gen_version_string(void)
{
        snprintf(rxrpc_version_string, sizeof(rxrpc_version_string),
                 "linux-%.49s AF_RXRPC", UTS_RELEASE);
}

/*
 * Reply to a version request
 */
void rxrpc_send_version_request(struct rxrpc_local *local,
                                struct rxrpc_host_header *hdr,
                                struct sk_buff *skb)
{
        struct rxrpc_wire_header whdr;
        struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
        struct sockaddr_rxrpc srx;
        struct msghdr msg;
        struct kvec iov[2];
        size_t len;
        int ret;

        _enter("");

        if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
                return;

        msg.msg_name    = &srx.transport;
        msg.msg_namelen = srx.transport_len;
        msg.msg_control = NULL;
        msg.msg_controllen = 0;
        msg.msg_flags   = 0;

        whdr.epoch      = htonl(sp->hdr.epoch);
        whdr.cid        = htonl(sp->hdr.cid);
        whdr.callNumber = htonl(sp->hdr.callNumber);
        whdr.seq        = 0;
        whdr.serial     = 0;
        whdr.type       = RXRPC_PACKET_TYPE_VERSION;
        whdr.flags      = RXRPC_LAST_PACKET | (~hdr->flags & RXRPC_CLIENT_INITIATED);
        whdr.userStatus = 0;
        whdr.securityIndex = 0;
        whdr._rsvd      = 0;
        whdr.serviceId  = htons(sp->hdr.serviceId);

        iov[0].iov_base = &whdr;
        iov[0].iov_len  = sizeof(whdr);
        iov[1].iov_base = (char *)rxrpc_version_string;
        iov[1].iov_len  = sizeof(rxrpc_version_string);

        len = iov[0].iov_len + iov[1].iov_len;

        ret = kernel_sendmsg(local->socket, &msg, iov, 2, len);
        if (ret < 0)
                trace_rxrpc_tx_fail(local->debug_id, 0, ret,
                                    rxrpc_tx_point_version_reply);
        else
                trace_rxrpc_tx_packet(local->debug_id, &whdr,
                                      rxrpc_tx_point_version_reply);

        _leave("");
}