// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Shared Memory Communications over RDMA (SMC-R) and RoCE
   *
   * Monitoring SMC transport protocol sockets
   *
   * Copyright IBM Corp. 2016
   *
   * Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/init.h>
  #include <linux/sock_diag.h>
  #include <linux/inet_diag.h>
  #include <linux/smc_diag.h>
  #include <net/netlink.h>
  #include <net/smc.h>
  
  #include "smc.h"
  #include "smc_core.h"

  struct smc_diag_dump_ctx {
  	int pos[2];
  };
  
  static struct smc_diag_dump_ctx *smc_dump_context(struct netlink_callback *cb)
  {
  	return (struct smc_diag_dump_ctx *)cb->ctx;
  }

  static void smc_gid_be16_convert(__u8 *buf, u8 *gid_raw)
  {
  	sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x",
  		be16_to_cpu(((__be16 *)gid_raw)[0]),
  		be16_to_cpu(((__be16 *)gid_raw)[1]),
  		be16_to_cpu(((__be16 *)gid_raw)[2]),
  		be16_to_cpu(((__be16 *)gid_raw)[3]),
  		be16_to_cpu(((__be16 *)gid_raw)[4]),
  		be16_to_cpu(((__be16 *)gid_raw)[5]),
  		be16_to_cpu(((__be16 *)gid_raw)[6]),
  		be16_to_cpu(((__be16 *)gid_raw)[7]));
  }
  
  static void smc_diag_msg_common_fill(struct smc_diag_msg *r, struct sock *sk)
  {
  	struct smc_sock *smc = smc_sk(sk);

  	memset(r, 0, sizeof(*r));

  	r->diag_family = sk->sk_family;

  	sock_diag_save_cookie(sk, r->id.idiag_cookie);

  	if (!smc->clcsock)
  		return;
  	r->id.idiag_sport = htons(smc->clcsock->sk->sk_num);
  	r->id.idiag_dport = smc->clcsock->sk->sk_dport;
  	r->id.idiag_if = smc->clcsock->sk->sk_bound_dev_if;

  	if (sk->sk_protocol == SMCPROTO_SMC) {

  		r->id.idiag_src[0] = smc->clcsock->sk->sk_rcv_saddr;
  		r->id.idiag_dst[0] = smc->clcsock->sk->sk_daddr;
  #if IS_ENABLED(CONFIG_IPV6)
  	} else if (sk->sk_protocol == SMCPROTO_SMC6) {

  		memcpy(&r->id.idiag_src, &smc->clcsock->sk->sk_v6_rcv_saddr,
  		       sizeof(smc->clcsock->sk->sk_v6_rcv_saddr));
  		memcpy(&r->id.idiag_dst, &smc->clcsock->sk->sk_v6_daddr,
  		       sizeof(smc->clcsock->sk->sk_v6_daddr));
  #endif
  	}

  }
  
  static int smc_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
  				   struct smc_diag_msg *r,
  				   struct user_namespace *user_ns)
  {
  	if (nla_put_u8(skb, SMC_DIAG_SHUTDOWN, sk->sk_shutdown))
  		return 1;
  
  	r->diag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
  	r->diag_inode = sock_i_ino(sk);
  	return 0;
  }
  
  static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb,
  			   struct netlink_callback *cb,
  			   const struct smc_diag_req *req,
  			   struct nlattr *bc)
  {
  	struct smc_sock *smc = smc_sk(sk);

  	struct smc_diag_fallback fallback;

  	struct user_namespace *user_ns;
  	struct smc_diag_msg *r;
  	struct nlmsghdr *nlh;
  
  	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
  			cb->nlh->nlmsg_type, sizeof(*r), NLM_F_MULTI);
  	if (!nlh)
  		return -EMSGSIZE;
  
  	r = nlmsg_data(nlh);
  	smc_diag_msg_common_fill(r, sk);
  	r->diag_state = sk->sk_state;

  	if (smc->use_fallback)
  		r->diag_mode = SMC_DIAG_MODE_FALLBACK_TCP;
  	else if (smc->conn.lgr && smc->conn.lgr->is_smcd)
  		r->diag_mode = SMC_DIAG_MODE_SMCD;
  	else
  		r->diag_mode = SMC_DIAG_MODE_SMCR;

  	user_ns = sk_user_ns(NETLINK_CB(cb->skb).sk);
  	if (smc_diag_msg_attrs_fill(sk, skb, r, user_ns))
  		goto errout;

  	fallback.reason = smc->fallback_rsn;
  	fallback.peer_diagnosis = smc->peer_diagnosis;
  	if (nla_put(skb, SMC_DIAG_FALLBACK, sizeof(fallback), &fallback) < 0)
  		goto errout;

  	if ((req->diag_ext & (1 << (SMC_DIAG_CONNINFO - 1))) &&
  	    smc->conn.alert_token_local) {

  		struct smc_connection *conn = &smc->conn;
  		struct smc_diag_conninfo cinfo = {
  			.token = conn->alert_token_local,

  			.sndbuf_size = conn->sndbuf_desc ?
  				conn->sndbuf_desc->len : 0,
  			.rmbe_size = conn->rmb_desc ? conn->rmb_desc->len : 0,

  			.peer_rmbe_size = conn->peer_rmbe_size,
  
  			.rx_prod.wrap = conn->local_rx_ctrl.prod.wrap,
  			.rx_prod.count = conn->local_rx_ctrl.prod.count,
  			.rx_cons.wrap = conn->local_rx_ctrl.cons.wrap,
  			.rx_cons.count = conn->local_rx_ctrl.cons.count,
  
  			.tx_prod.wrap = conn->local_tx_ctrl.prod.wrap,
  			.tx_prod.count = conn->local_tx_ctrl.prod.count,
  			.tx_cons.wrap = conn->local_tx_ctrl.cons.wrap,
  			.tx_cons.count = conn->local_tx_ctrl.cons.count,
  
  			.tx_prod_flags =
  				*(u8 *)&conn->local_tx_ctrl.prod_flags,
  			.tx_conn_state_flags =
  				*(u8 *)&conn->local_tx_ctrl.conn_state_flags,
  			.rx_prod_flags = *(u8 *)&conn->local_rx_ctrl.prod_flags,
  			.rx_conn_state_flags =
  				*(u8 *)&conn->local_rx_ctrl.conn_state_flags,
  
  			.tx_prep.wrap = conn->tx_curs_prep.wrap,
  			.tx_prep.count = conn->tx_curs_prep.count,
  			.tx_sent.wrap = conn->tx_curs_sent.wrap,
  			.tx_sent.count = conn->tx_curs_sent.count,
  			.tx_fin.wrap = conn->tx_curs_fin.wrap,
  			.tx_fin.count = conn->tx_curs_fin.count,
  		};
  
  		if (nla_put(skb, SMC_DIAG_CONNINFO, sizeof(cinfo), &cinfo) < 0)
  			goto errout;
  	}

  	if (smc->conn.lgr && !smc->conn.lgr->is_smcd &&
  	    (req->diag_ext & (1 << (SMC_DIAG_LGRINFO - 1))) &&

  	    !list_empty(&smc->conn.lgr->list)) {

  		struct smc_diag_lgrinfo linfo = {
  			.role = smc->conn.lgr->role,
  			.lnk[0].ibport = smc->conn.lgr->lnk[0].ibport,
  			.lnk[0].link_id = smc->conn.lgr->lnk[0].link_id,
  		};
  
  		memcpy(linfo.lnk[0].ibname,
  		       smc->conn.lgr->lnk[0].smcibdev->ibdev->name,
  		       sizeof(smc->conn.lgr->lnk[0].smcibdev->ibdev->name));
  		smc_gid_be16_convert(linfo.lnk[0].gid,

  				     smc->conn.lgr->lnk[0].gid);

  		smc_gid_be16_convert(linfo.lnk[0].peer_gid,
  				     smc->conn.lgr->lnk[0].peer_gid);
  
  		if (nla_put(skb, SMC_DIAG_LGRINFO, sizeof(linfo), &linfo) < 0)
  			goto errout;
  	}

  	if (smc->conn.lgr && smc->conn.lgr->is_smcd &&
  	    (req->diag_ext & (1 << (SMC_DIAG_DMBINFO - 1))) &&
  	    !list_empty(&smc->conn.lgr->list)) {
  		struct smc_connection *conn = &smc->conn;

  		struct smcd_diag_dmbinfo dinfo;
  
  		memset(&dinfo, 0, sizeof(dinfo));
  
  		dinfo.linkid = *((u32 *)conn->lgr->id);
  		dinfo.peer_gid = conn->lgr->peer_gid;
  		dinfo.my_gid = conn->lgr->smcd->local_gid;
  		dinfo.token = conn->rmb_desc->token;
  		dinfo.peer_token = conn->peer_token;

  
  		if (nla_put(skb, SMC_DIAG_DMBINFO, sizeof(dinfo), &dinfo) < 0)
  			goto errout;
  	}

  
  	nlmsg_end(skb, nlh);
  	return 0;
  
  errout:
  	nlmsg_cancel(skb, nlh);
  	return -EMSGSIZE;
  }

  static int smc_diag_dump_proto(struct proto *prot, struct sk_buff *skb,

  			       struct netlink_callback *cb, int p_type)

  {

  	struct smc_diag_dump_ctx *cb_ctx = smc_dump_context(cb);

  	struct net *net = sock_net(skb->sk);

  	int snum = cb_ctx->pos[p_type];

  	struct nlattr *bc = NULL;
  	struct hlist_head *head;

  	int rc = 0, num = 0;

  	struct sock *sk;

  	read_lock(&prot->h.smc_hash->lock);
  	head = &prot->h.smc_hash->ht;

  	if (hlist_empty(head))
  		goto out;
  
  	sk_for_each(sk, head) {
  		if (!net_eq(sock_net(sk), net))
  			continue;

  		if (num < snum)
  			goto next;

  		rc = __smc_diag_dump(sk, skb, cb, nlmsg_data(cb->nlh), bc);

  		if (rc < 0)
  			goto out;
  next:
  		num++;

  	}
  
  out:

  	read_unlock(&prot->h.smc_hash->lock);

  	cb_ctx->pos[p_type] = num;

  	return rc;
  }
  
  static int smc_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	int rc = 0;

  	rc = smc_diag_dump_proto(&smc_proto, skb, cb, SMCPROTO_SMC);

  	if (!rc)

  		smc_diag_dump_proto(&smc_proto6, skb, cb, SMCPROTO_SMC6);
  	return skb->len;

  }
  
  static int smc_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
  {
  	struct net *net = sock_net(skb->sk);
  
  	if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY &&
  	    h->nlmsg_flags & NLM_F_DUMP) {
  		{
  			struct netlink_dump_control c = {
  				.dump = smc_diag_dump,
  				.min_dump_alloc = SKB_WITH_OVERHEAD(32768),
  			};
  			return netlink_dump_start(net->diag_nlsk, skb, h, &c);
  		}
  	}
  	return 0;
  }
  
  static const struct sock_diag_handler smc_diag_handler = {
  	.family = AF_SMC,
  	.dump = smc_diag_handler_dump,
  };
  
  static int __init smc_diag_init(void)
  {
  	return sock_diag_register(&smc_diag_handler);
  }
  
  static void __exit smc_diag_exit(void)
  {
  	sock_diag_unregister(&smc_diag_handler);
  }
  
  module_init(smc_diag_init);
  module_exit(smc_diag_exit);
  MODULE_LICENSE("GPL");
  MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 43 /* AF_SMC */);