1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  * Monitoring SMC transport protocol sockets
6  *
7  * Copyright IBM Corp. 2016
8  *
9  * Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/init.h>
16 #include <linux/sock_diag.h>
17 #include <linux/inet_diag.h>
18 #include <linux/smc_diag.h>
19 #include <net/netlink.h>
20 #include <net/smc.h>
21 
22 #include "smc.h"
23 #include "smc_core.h"
24 #include "smc_ism.h"
25 
26 struct smc_diag_dump_ctx {
27 	int pos[2];
28 };
29 
smc_dump_context(struct netlink_callback * cb)30 static struct smc_diag_dump_ctx *smc_dump_context(struct netlink_callback *cb)
31 {
32 	return (struct smc_diag_dump_ctx *)cb->ctx;
33 }
34 
smc_diag_msg_common_fill(struct smc_diag_msg * r,struct sock * sk)35 static void smc_diag_msg_common_fill(struct smc_diag_msg *r, struct sock *sk)
36 {
37 	struct smc_sock *smc = smc_sk(sk);
38 
39 	memset(r, 0, sizeof(*r));
40 	r->diag_family = sk->sk_family;
41 	sock_diag_save_cookie(sk, r->id.idiag_cookie);
42 	if (!smc->clcsock)
43 		return;
44 	r->id.idiag_sport = htons(smc->clcsock->sk->sk_num);
45 	r->id.idiag_dport = smc->clcsock->sk->sk_dport;
46 	r->id.idiag_if = smc->clcsock->sk->sk_bound_dev_if;
47 	if (sk->sk_protocol == SMCPROTO_SMC) {
48 		r->id.idiag_src[0] = smc->clcsock->sk->sk_rcv_saddr;
49 		r->id.idiag_dst[0] = smc->clcsock->sk->sk_daddr;
50 #if IS_ENABLED(CONFIG_IPV6)
51 	} else if (sk->sk_protocol == SMCPROTO_SMC6) {
52 		memcpy(&r->id.idiag_src, &smc->clcsock->sk->sk_v6_rcv_saddr,
53 		       sizeof(smc->clcsock->sk->sk_v6_rcv_saddr));
54 		memcpy(&r->id.idiag_dst, &smc->clcsock->sk->sk_v6_daddr,
55 		       sizeof(smc->clcsock->sk->sk_v6_daddr));
56 #endif
57 	}
58 }
59 
smc_diag_msg_attrs_fill(struct sock * sk,struct sk_buff * skb,struct smc_diag_msg * r,struct user_namespace * user_ns)60 static int smc_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
61 				   struct smc_diag_msg *r,
62 				   struct user_namespace *user_ns)
63 {
64 	if (nla_put_u8(skb, SMC_DIAG_SHUTDOWN, sk->sk_shutdown))
65 		return 1;
66 
67 	r->diag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
68 	r->diag_inode = sock_i_ino(sk);
69 	return 0;
70 }
71 
__smc_diag_dump(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,const struct smc_diag_req * req,struct nlattr * bc)72 static int __smc_diag_dump(struct sock *sk, struct sk_buff *skb,
73 			   struct netlink_callback *cb,
74 			   const struct smc_diag_req *req,
75 			   struct nlattr *bc)
76 {
77 	struct smc_sock *smc = smc_sk(sk);
78 	struct smc_diag_fallback fallback;
79 	struct user_namespace *user_ns;
80 	struct smc_diag_msg *r;
81 	struct nlmsghdr *nlh;
82 
83 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
84 			cb->nlh->nlmsg_type, sizeof(*r), NLM_F_MULTI);
85 	if (!nlh)
86 		return -EMSGSIZE;
87 
88 	r = nlmsg_data(nlh);
89 	smc_diag_msg_common_fill(r, sk);
90 	r->diag_state = sk->sk_state;
91 	if (smc->use_fallback)
92 		r->diag_mode = SMC_DIAG_MODE_FALLBACK_TCP;
93 	else if (smc_conn_lgr_valid(&smc->conn) && smc->conn.lgr->is_smcd)
94 		r->diag_mode = SMC_DIAG_MODE_SMCD;
95 	else
96 		r->diag_mode = SMC_DIAG_MODE_SMCR;
97 	user_ns = sk_user_ns(NETLINK_CB(cb->skb).sk);
98 	if (smc_diag_msg_attrs_fill(sk, skb, r, user_ns))
99 		goto errout;
100 
101 	fallback.reason = smc->fallback_rsn;
102 	fallback.peer_diagnosis = smc->peer_diagnosis;
103 	if (nla_put(skb, SMC_DIAG_FALLBACK, sizeof(fallback), &fallback) < 0)
104 		goto errout;
105 
106 	if ((req->diag_ext & (1 << (SMC_DIAG_CONNINFO - 1))) &&
107 	    smc->conn.alert_token_local) {
108 		struct smc_connection *conn = &smc->conn;
109 		struct smc_diag_conninfo cinfo = {
110 			.token = conn->alert_token_local,
111 			.sndbuf_size = conn->sndbuf_desc ?
112 				conn->sndbuf_desc->len : 0,
113 			.rmbe_size = conn->rmb_desc ? conn->rmb_desc->len : 0,
114 			.peer_rmbe_size = conn->peer_rmbe_size,
115 
116 			.rx_prod.wrap = conn->local_rx_ctrl.prod.wrap,
117 			.rx_prod.count = conn->local_rx_ctrl.prod.count,
118 			.rx_cons.wrap = conn->local_rx_ctrl.cons.wrap,
119 			.rx_cons.count = conn->local_rx_ctrl.cons.count,
120 
121 			.tx_prod.wrap = conn->local_tx_ctrl.prod.wrap,
122 			.tx_prod.count = conn->local_tx_ctrl.prod.count,
123 			.tx_cons.wrap = conn->local_tx_ctrl.cons.wrap,
124 			.tx_cons.count = conn->local_tx_ctrl.cons.count,
125 
126 			.tx_prod_flags =
127 				*(u8 *)&conn->local_tx_ctrl.prod_flags,
128 			.tx_conn_state_flags =
129 				*(u8 *)&conn->local_tx_ctrl.conn_state_flags,
130 			.rx_prod_flags = *(u8 *)&conn->local_rx_ctrl.prod_flags,
131 			.rx_conn_state_flags =
132 				*(u8 *)&conn->local_rx_ctrl.conn_state_flags,
133 
134 			.tx_prep.wrap = conn->tx_curs_prep.wrap,
135 			.tx_prep.count = conn->tx_curs_prep.count,
136 			.tx_sent.wrap = conn->tx_curs_sent.wrap,
137 			.tx_sent.count = conn->tx_curs_sent.count,
138 			.tx_fin.wrap = conn->tx_curs_fin.wrap,
139 			.tx_fin.count = conn->tx_curs_fin.count,
140 		};
141 
142 		if (nla_put(skb, SMC_DIAG_CONNINFO, sizeof(cinfo), &cinfo) < 0)
143 			goto errout;
144 	}
145 
146 	if (smc_conn_lgr_valid(&smc->conn) && !smc->conn.lgr->is_smcd &&
147 	    (req->diag_ext & (1 << (SMC_DIAG_LGRINFO - 1))) &&
148 	    !list_empty(&smc->conn.lgr->list)) {
149 		struct smc_link *link = smc->conn.lnk;
150 
151 		struct smc_diag_lgrinfo linfo = {
152 			.role = smc->conn.lgr->role,
153 			.lnk[0].ibport = link->ibport,
154 			.lnk[0].link_id = link->link_id,
155 		};
156 
157 		memcpy(linfo.lnk[0].ibname, link->smcibdev->ibdev->name,
158 		       sizeof(link->smcibdev->ibdev->name));
159 		smc_gid_be16_convert(linfo.lnk[0].gid, link->gid);
160 		smc_gid_be16_convert(linfo.lnk[0].peer_gid, link->peer_gid);
161 
162 		if (nla_put(skb, SMC_DIAG_LGRINFO, sizeof(linfo), &linfo) < 0)
163 			goto errout;
164 	}
165 	if (smc_conn_lgr_valid(&smc->conn) && smc->conn.lgr->is_smcd &&
166 	    (req->diag_ext & (1 << (SMC_DIAG_DMBINFO - 1))) &&
167 	    !list_empty(&smc->conn.lgr->list) && smc->conn.rmb_desc) {
168 		struct smc_connection *conn = &smc->conn;
169 		struct smcd_diag_dmbinfo dinfo;
170 		struct smcd_dev *smcd = conn->lgr->smcd;
171 		struct smcd_gid smcd_gid;
172 
173 		memset(&dinfo, 0, sizeof(dinfo));
174 
175 		dinfo.linkid = *((u32 *)conn->lgr->id);
176 		dinfo.peer_gid = conn->lgr->peer_gid.gid;
177 		dinfo.peer_gid_ext = conn->lgr->peer_gid.gid_ext;
178 		smcd->ops->get_local_gid(smcd, &smcd_gid);
179 		dinfo.my_gid = smcd_gid.gid;
180 		dinfo.my_gid_ext = smcd_gid.gid_ext;
181 		dinfo.token = conn->rmb_desc->token;
182 		dinfo.peer_token = conn->peer_token;
183 
184 		if (nla_put(skb, SMC_DIAG_DMBINFO, sizeof(dinfo), &dinfo) < 0)
185 			goto errout;
186 	}
187 
188 	nlmsg_end(skb, nlh);
189 	return 0;
190 
191 errout:
192 	nlmsg_cancel(skb, nlh);
193 	return -EMSGSIZE;
194 }
195 
smc_diag_dump_proto(struct proto * prot,struct sk_buff * skb,struct netlink_callback * cb,int p_type)196 static int smc_diag_dump_proto(struct proto *prot, struct sk_buff *skb,
197 			       struct netlink_callback *cb, int p_type)
198 {
199 	struct smc_diag_dump_ctx *cb_ctx = smc_dump_context(cb);
200 	struct net *net = sock_net(skb->sk);
201 	int snum = cb_ctx->pos[p_type];
202 	struct nlattr *bc = NULL;
203 	struct hlist_head *head;
204 	int rc = 0, num = 0;
205 	struct sock *sk;
206 
207 	read_lock(&prot->h.smc_hash->lock);
208 	head = &prot->h.smc_hash->ht;
209 	if (hlist_empty(head))
210 		goto out;
211 
212 	sk_for_each(sk, head) {
213 		if (!net_eq(sock_net(sk), net))
214 			continue;
215 		if (num < snum)
216 			goto next;
217 		rc = __smc_diag_dump(sk, skb, cb, nlmsg_data(cb->nlh), bc);
218 		if (rc < 0)
219 			goto out;
220 next:
221 		num++;
222 	}
223 
224 out:
225 	read_unlock(&prot->h.smc_hash->lock);
226 	cb_ctx->pos[p_type] = num;
227 	return rc;
228 }
229 
smc_diag_dump(struct sk_buff * skb,struct netlink_callback * cb)230 static int smc_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
231 {
232 	int rc = 0;
233 
234 	rc = smc_diag_dump_proto(&smc_proto, skb, cb, SMCPROTO_SMC);
235 	if (!rc)
236 		smc_diag_dump_proto(&smc_proto6, skb, cb, SMCPROTO_SMC6);
237 	return skb->len;
238 }
239 
smc_diag_handler_dump(struct sk_buff * skb,struct nlmsghdr * h)240 static int smc_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
241 {
242 	struct net *net = sock_net(skb->sk);
243 
244 	if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY &&
245 	    h->nlmsg_flags & NLM_F_DUMP) {
246 		{
247 			struct netlink_dump_control c = {
248 				.dump = smc_diag_dump,
249 				.min_dump_alloc = SKB_WITH_OVERHEAD(32768),
250 			};
251 			return netlink_dump_start(net->diag_nlsk, skb, h, &c);
252 		}
253 	}
254 	return 0;
255 }
256 
257 static const struct sock_diag_handler smc_diag_handler = {
258 	.owner = THIS_MODULE,
259 	.family = AF_SMC,
260 	.dump = smc_diag_handler_dump,
261 };
262 
smc_diag_init(void)263 static int __init smc_diag_init(void)
264 {
265 	return sock_diag_register(&smc_diag_handler);
266 }
267 
smc_diag_exit(void)268 static void __exit smc_diag_exit(void)
269 {
270 	sock_diag_unregister(&smc_diag_handler);
271 }
272 
273 module_init(smc_diag_init);
274 module_exit(smc_diag_exit);
275 MODULE_LICENSE("GPL");
276 MODULE_DESCRIPTION("SMC socket monitoring via SOCK_DIAG");
277 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 43 /* AF_SMC */);
278 MODULE_ALIAS_GENL_FAMILY(SMCR_GENL_FAMILY_NAME);
279