1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright Gavin Shan, IBM Corporation 2016.
4 */
5
6#include <linux/module.h>
7#include <linux/kernel.h>
8#include <linux/init.h>
9#include <linux/etherdevice.h>
10#include <linux/netdevice.h>
11#include <linux/skbuff.h>
12
13#include <net/ncsi.h>
14#include <net/net_namespace.h>
15#include <net/sock.h>
16#include <net/genetlink.h>
17
18#include "internal.h"
19#include "ncsi-pkt.h"
20
21static const int padding_bytes = 26;
22
23u32 ncsi_calculate_checksum(unsigned char *data, int len)
24{
25 u32 checksum = 0;
26 int i;
27
28 for (i = 0; i < len; i += 2)
29 checksum += (((u32)data[i] << 8) | data[i + 1]);
30
31 checksum = (~checksum + 1);
32 return checksum;
33}
34
35/* This function should be called after the data area has been
36 * populated completely.
37 */
38static void ncsi_cmd_build_header(struct ncsi_pkt_hdr *h,
39 struct ncsi_cmd_arg *nca)
40{
41 u32 checksum;
42 __be32 *pchecksum;
43
44 h->mc_id = 0;
45 h->revision = NCSI_PKT_REVISION;
46 h->reserved = 0;
47 h->id = nca->id;
48 h->type = nca->type;
49 h->channel = NCSI_TO_CHANNEL(nca->package,
50 nca->channel);
51 h->length = htons(nca->payload);
52 h->reserved1[0] = 0;
53 h->reserved1[1] = 0;
54
55 /* Fill with calculated checksum */
56 checksum = ncsi_calculate_checksum(data: (unsigned char *)h,
57 len: sizeof(*h) + nca->payload);
58 pchecksum = (__be32 *)((void *)h + sizeof(struct ncsi_pkt_hdr) +
59 ALIGN(nca->payload, 4));
60 *pchecksum = htonl(checksum);
61}
62
63static int ncsi_cmd_handler_default(struct sk_buff *skb,
64 struct ncsi_cmd_arg *nca)
65{
66 struct ncsi_cmd_pkt *cmd;
67
68 cmd = skb_put_zero(skb, len: sizeof(*cmd));
69 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
70
71 return 0;
72}
73
74static int ncsi_cmd_handler_sp(struct sk_buff *skb,
75 struct ncsi_cmd_arg *nca)
76{
77 struct ncsi_cmd_sp_pkt *cmd;
78
79 cmd = skb_put_zero(skb, len: sizeof(*cmd));
80 cmd->hw_arbitration = nca->bytes[0];
81 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
82
83 return 0;
84}
85
86static int ncsi_cmd_handler_dc(struct sk_buff *skb,
87 struct ncsi_cmd_arg *nca)
88{
89 struct ncsi_cmd_dc_pkt *cmd;
90
91 cmd = skb_put_zero(skb, len: sizeof(*cmd));
92 cmd->ald = nca->bytes[0];
93 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
94
95 return 0;
96}
97
98static int ncsi_cmd_handler_rc(struct sk_buff *skb,
99 struct ncsi_cmd_arg *nca)
100{
101 struct ncsi_cmd_rc_pkt *cmd;
102
103 cmd = skb_put_zero(skb, len: sizeof(*cmd));
104 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
105
106 return 0;
107}
108
109static int ncsi_cmd_handler_ae(struct sk_buff *skb,
110 struct ncsi_cmd_arg *nca)
111{
112 struct ncsi_cmd_ae_pkt *cmd;
113
114 cmd = skb_put_zero(skb, len: sizeof(*cmd));
115 cmd->mc_id = nca->bytes[0];
116 cmd->mode = htonl(nca->dwords[1]);
117 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
118
119 return 0;
120}
121
122static int ncsi_cmd_handler_sl(struct sk_buff *skb,
123 struct ncsi_cmd_arg *nca)
124{
125 struct ncsi_cmd_sl_pkt *cmd;
126
127 cmd = skb_put_zero(skb, len: sizeof(*cmd));
128 cmd->mode = htonl(nca->dwords[0]);
129 cmd->oem_mode = htonl(nca->dwords[1]);
130 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
131
132 return 0;
133}
134
135static int ncsi_cmd_handler_svf(struct sk_buff *skb,
136 struct ncsi_cmd_arg *nca)
137{
138 struct ncsi_cmd_svf_pkt *cmd;
139
140 cmd = skb_put_zero(skb, len: sizeof(*cmd));
141 cmd->vlan = htons(nca->words[1]);
142 cmd->index = nca->bytes[6];
143 cmd->enable = nca->bytes[7];
144 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
145
146 return 0;
147}
148
149static int ncsi_cmd_handler_ev(struct sk_buff *skb,
150 struct ncsi_cmd_arg *nca)
151{
152 struct ncsi_cmd_ev_pkt *cmd;
153
154 cmd = skb_put_zero(skb, len: sizeof(*cmd));
155 cmd->mode = nca->bytes[3];
156 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
157
158 return 0;
159}
160
161static int ncsi_cmd_handler_sma(struct sk_buff *skb,
162 struct ncsi_cmd_arg *nca)
163{
164 struct ncsi_cmd_sma_pkt *cmd;
165 int i;
166
167 cmd = skb_put_zero(skb, len: sizeof(*cmd));
168 for (i = 0; i < 6; i++)
169 cmd->mac[i] = nca->bytes[i];
170 cmd->index = nca->bytes[6];
171 cmd->at_e = nca->bytes[7];
172 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
173
174 return 0;
175}
176
177static int ncsi_cmd_handler_ebf(struct sk_buff *skb,
178 struct ncsi_cmd_arg *nca)
179{
180 struct ncsi_cmd_ebf_pkt *cmd;
181
182 cmd = skb_put_zero(skb, len: sizeof(*cmd));
183 cmd->mode = htonl(nca->dwords[0]);
184 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
185
186 return 0;
187}
188
189static int ncsi_cmd_handler_egmf(struct sk_buff *skb,
190 struct ncsi_cmd_arg *nca)
191{
192 struct ncsi_cmd_egmf_pkt *cmd;
193
194 cmd = skb_put_zero(skb, len: sizeof(*cmd));
195 cmd->mode = htonl(nca->dwords[0]);
196 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
197
198 return 0;
199}
200
201static int ncsi_cmd_handler_snfc(struct sk_buff *skb,
202 struct ncsi_cmd_arg *nca)
203{
204 struct ncsi_cmd_snfc_pkt *cmd;
205
206 cmd = skb_put_zero(skb, len: sizeof(*cmd));
207 cmd->mode = nca->bytes[0];
208 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
209
210 return 0;
211}
212
213static int ncsi_cmd_handler_oem(struct sk_buff *skb,
214 struct ncsi_cmd_arg *nca)
215{
216 struct ncsi_cmd_oem_pkt *cmd;
217 unsigned int len;
218 int payload;
219 /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2
220 * requires payload to be padded with 0 to
221 * 32-bit boundary before the checksum field.
222 * Ensure the padding bytes are accounted for in
223 * skb allocation
224 */
225
226 payload = ALIGN(nca->payload, 4);
227 len = sizeof(struct ncsi_cmd_pkt_hdr) + 4;
228 len += max(payload, padding_bytes);
229
230 cmd = skb_put_zero(skb, len);
231 unsafe_memcpy(&cmd->mfr_id, nca->data, nca->payload,
232 /* skb allocated with enough to load the payload */);
233 ncsi_cmd_build_header(h: &cmd->cmd.common, nca);
234
235 return 0;
236}
237
238static struct ncsi_cmd_handler {
239 unsigned char type;
240 int payload;
241 int (*handler)(struct sk_buff *skb,
242 struct ncsi_cmd_arg *nca);
243} ncsi_cmd_handlers[] = {
244 { NCSI_PKT_CMD_CIS, 0, ncsi_cmd_handler_default },
245 { NCSI_PKT_CMD_SP, 4, ncsi_cmd_handler_sp },
246 { NCSI_PKT_CMD_DP, 0, ncsi_cmd_handler_default },
247 { NCSI_PKT_CMD_EC, 0, ncsi_cmd_handler_default },
248 { NCSI_PKT_CMD_DC, 4, ncsi_cmd_handler_dc },
249 { NCSI_PKT_CMD_RC, 4, ncsi_cmd_handler_rc },
250 { NCSI_PKT_CMD_ECNT, 0, ncsi_cmd_handler_default },
251 { NCSI_PKT_CMD_DCNT, 0, ncsi_cmd_handler_default },
252 { NCSI_PKT_CMD_AE, 8, ncsi_cmd_handler_ae },
253 { NCSI_PKT_CMD_SL, 8, ncsi_cmd_handler_sl },
254 { NCSI_PKT_CMD_GLS, 0, ncsi_cmd_handler_default },
255 { NCSI_PKT_CMD_SVF, 8, ncsi_cmd_handler_svf },
256 { NCSI_PKT_CMD_EV, 4, ncsi_cmd_handler_ev },
257 { NCSI_PKT_CMD_DV, 0, ncsi_cmd_handler_default },
258 { NCSI_PKT_CMD_SMA, 8, ncsi_cmd_handler_sma },
259 { NCSI_PKT_CMD_EBF, 4, ncsi_cmd_handler_ebf },
260 { NCSI_PKT_CMD_DBF, 0, ncsi_cmd_handler_default },
261 { NCSI_PKT_CMD_EGMF, 4, ncsi_cmd_handler_egmf },
262 { NCSI_PKT_CMD_DGMF, 0, ncsi_cmd_handler_default },
263 { NCSI_PKT_CMD_SNFC, 4, ncsi_cmd_handler_snfc },
264 { NCSI_PKT_CMD_GVI, 0, ncsi_cmd_handler_default },
265 { NCSI_PKT_CMD_GC, 0, ncsi_cmd_handler_default },
266 { NCSI_PKT_CMD_GP, 0, ncsi_cmd_handler_default },
267 { NCSI_PKT_CMD_GCPS, 0, ncsi_cmd_handler_default },
268 { NCSI_PKT_CMD_GNS, 0, ncsi_cmd_handler_default },
269 { NCSI_PKT_CMD_GNPTS, 0, ncsi_cmd_handler_default },
270 { NCSI_PKT_CMD_GPS, 0, ncsi_cmd_handler_default },
271 { NCSI_PKT_CMD_OEM, -1, ncsi_cmd_handler_oem },
272 { NCSI_PKT_CMD_PLDM, 0, NULL },
273 { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default }
274};
275
276static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
277{
278 struct ncsi_dev_priv *ndp = nca->ndp;
279 struct ncsi_dev *nd = &ndp->ndev;
280 struct net_device *dev = nd->dev;
281 int hlen = LL_RESERVED_SPACE(dev);
282 int tlen = dev->needed_tailroom;
283 int payload;
284 int len = hlen + tlen;
285 struct sk_buff *skb;
286 struct ncsi_request *nr;
287
288 nr = ncsi_alloc_request(ndp, req_flags: nca->req_flags);
289 if (!nr)
290 return NULL;
291
292 /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
293 * Payload needs padding so that the checksum field following payload is
294 * aligned to 32-bit boundary.
295 * The packet needs padding if its payload is less than 26 bytes to
296 * meet 64 bytes minimal ethernet frame length.
297 */
298 len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
299 payload = ALIGN(nca->payload, 4);
300 len += max(payload, padding_bytes);
301
302 /* Allocate skb */
303 skb = alloc_skb(size: len, GFP_ATOMIC);
304 if (!skb) {
305 ncsi_free_request(nr);
306 return NULL;
307 }
308
309 nr->cmd = skb;
310 skb_reserve(skb, len: hlen);
311 skb_reset_network_header(skb);
312
313 skb->dev = dev;
314 skb->protocol = htons(ETH_P_NCSI);
315
316 return nr;
317}
318
319int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca)
320{
321 struct ncsi_cmd_handler *nch = NULL;
322 struct ncsi_request *nr;
323 unsigned char type;
324 struct ethhdr *eh;
325 int i, ret;
326
327 /* Use OEM generic handler for Netlink request */
328 if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN)
329 type = NCSI_PKT_CMD_OEM;
330 else
331 type = nca->type;
332
333 /* Search for the handler */
334 for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) {
335 if (ncsi_cmd_handlers[i].type == type) {
336 if (ncsi_cmd_handlers[i].handler)
337 nch = &ncsi_cmd_handlers[i];
338 else
339 nch = NULL;
340
341 break;
342 }
343 }
344
345 if (!nch) {
346 netdev_err(dev: nca->ndp->ndev.dev,
347 format: "Cannot send packet with type 0x%02x\n", nca->type);
348 return -ENOENT;
349 }
350
351 /* Get packet payload length and allocate the request
352 * It is expected that if length set as negative in
353 * handler structure means caller is initializing it
354 * and setting length in nca before calling xmit function
355 */
356 if (nch->payload >= 0)
357 nca->payload = nch->payload;
358 nr = ncsi_alloc_command(nca);
359 if (!nr)
360 return -ENOMEM;
361
362 /* track netlink information */
363 if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN) {
364 nr->snd_seq = nca->info->snd_seq;
365 nr->snd_portid = nca->info->snd_portid;
366 nr->nlhdr = *nca->info->nlhdr;
367 }
368
369 /* Prepare the packet */
370 nca->id = nr->id;
371 ret = nch->handler(nr->cmd, nca);
372 if (ret) {
373 ncsi_free_request(nr);
374 return ret;
375 }
376
377 /* Fill the ethernet header */
378 eh = skb_push(skb: nr->cmd, len: sizeof(*eh));
379 eh->h_proto = htons(ETH_P_NCSI);
380 eth_broadcast_addr(addr: eh->h_dest);
381
382 /* If mac address received from device then use it for
383 * source address as unicast address else use broadcast
384 * address as source address
385 */
386 if (nca->ndp->gma_flag == 1)
387 memcpy(eh->h_source, nca->ndp->ndev.dev->dev_addr, ETH_ALEN);
388 else
389 eth_broadcast_addr(addr: eh->h_source);
390
391 /* Start the timer for the request that might not have
392 * corresponding response. Given NCSI is an internal
393 * connection a 1 second delay should be sufficient.
394 */
395 nr->enabled = true;
396 mod_timer(timer: &nr->timer, expires: jiffies + 1 * HZ);
397
398 /* Send NCSI packet */
399 skb_get(skb: nr->cmd);
400 ret = dev_queue_xmit(skb: nr->cmd);
401 if (ret < 0) {
402 ncsi_free_request(nr);
403 return ret;
404 }
405
406 return 0;
407}
408

source code of linux/net/ncsi/ncsi-cmd.c