xref: /qemu/hw/ipmi/ipmi_bmc_extern.c (revision 06b40d250ecfa1633209c2e431a7a38acfd03a98)
1 /*
2  * IPMI BMC external connection
3  *
4  * Copyright (c) 2015 Corey Minyard, MontaVista Software, LLC
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 /*
26  * This is designed to connect with OpenIPMI's lanserv serial interface
27  * using the "VM" connection type.  See that for details.
28  */
29 
30 #include "qemu/osdep.h"
31 #include "qemu/error-report.h"
32 #include "qemu/module.h"
33 #include "qapi/error.h"
34 #include "qemu/timer.h"
35 #include "chardev/char-fe.h"
36 #include "hw/ipmi/ipmi.h"
37 #include "hw/qdev-properties.h"
38 #include "hw/qdev-properties-system.h"
39 #include "migration/vmstate.h"
40 #include "qom/object.h"
41 
42 #define VM_MSG_CHAR        0xA0 /* Marks end of message */
43 #define VM_CMD_CHAR        0xA1 /* Marks end of a command */
44 #define VM_ESCAPE_CHAR     0xAA /* Set bit 4 from the next byte to 0 */
45 
46 #define VM_PROTOCOL_VERSION        1
47 #define VM_CMD_VERSION             0xff /* A version number byte follows */
48 #define VM_CMD_NOATTN              0x00
49 #define VM_CMD_ATTN                0x01
50 #define VM_CMD_ATTN_IRQ            0x02
51 #define VM_CMD_POWEROFF            0x03
52 #define VM_CMD_RESET               0x04
53 #define VM_CMD_ENABLE_IRQ          0x05 /* Enable/disable the messaging irq */
54 #define VM_CMD_DISABLE_IRQ         0x06
55 #define VM_CMD_SEND_NMI            0x07
56 #define VM_CMD_CAPABILITIES        0x08
57 #define   VM_CAPABILITIES_POWER    0x01
58 #define   VM_CAPABILITIES_RESET    0x02
59 #define   VM_CAPABILITIES_IRQ      0x04
60 #define   VM_CAPABILITIES_NMI      0x08
61 #define   VM_CAPABILITIES_ATTN     0x10
62 #define   VM_CAPABILITIES_GRACEFUL_SHUTDOWN 0x20
63 #define VM_CMD_GRACEFUL_SHUTDOWN   0x09
64 
65 #define TYPE_IPMI_BMC_EXTERN "ipmi-bmc-extern"
66 OBJECT_DECLARE_SIMPLE_TYPE(IPMIBmcExtern, IPMI_BMC_EXTERN)
67 struct IPMIBmcExtern {
68     IPMIBmc parent;
69 
70     CharBackend chr;
71 
72     bool connected;
73 
74     unsigned char inbuf[MAX_IPMI_MSG_SIZE + 2];
75     unsigned int inpos;
76     bool in_escape;
77     bool in_too_many;
78     bool waiting_rsp;
79     bool sending_cmd;
80 
81     unsigned char outbuf[(MAX_IPMI_MSG_SIZE + 2) * 2 + 1];
82     unsigned int outpos;
83     unsigned int outlen;
84 
85     struct QEMUTimer *extern_timer;
86 
87     /* A reset event is pending to be sent upstream. */
88     bool send_reset;
89 };
90 
91 static unsigned char
ipmb_checksum(const unsigned char * data,int size,unsigned char start)92 ipmb_checksum(const unsigned char *data, int size, unsigned char start)
93 {
94         unsigned char csum = start;
95 
96         for (; size > 0; size--, data++) {
97                 csum += *data;
98         }
99         return csum;
100 }
101 
continue_send(IPMIBmcExtern * ibe)102 static void continue_send(IPMIBmcExtern *ibe)
103 {
104     int ret;
105     if (ibe->outlen == 0) {
106         goto check_reset;
107     }
108  send:
109     ret = qemu_chr_fe_write(&ibe->chr, ibe->outbuf + ibe->outpos,
110                             ibe->outlen - ibe->outpos);
111     if (ret > 0) {
112         ibe->outpos += ret;
113     }
114     if (ibe->outpos < ibe->outlen) {
115         /* Not fully transmitted, try again in a 10ms */
116         timer_mod_ns(ibe->extern_timer,
117                      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 10000000);
118     } else {
119         /* Sent */
120         ibe->outlen = 0;
121         ibe->outpos = 0;
122         if (!ibe->sending_cmd) {
123             ibe->waiting_rsp = true;
124         } else {
125             ibe->sending_cmd = false;
126         }
127     check_reset:
128         if (ibe->connected && ibe->send_reset) {
129             /* Send the reset */
130             ibe->outbuf[0] = VM_CMD_RESET;
131             ibe->outbuf[1] = VM_CMD_CHAR;
132             ibe->outlen = 2;
133             ibe->outpos = 0;
134             ibe->send_reset = false;
135             ibe->sending_cmd = true;
136             goto send;
137         }
138 
139         if (ibe->waiting_rsp) {
140             /* Make sure we get a response within 4 seconds. */
141             timer_mod_ns(ibe->extern_timer,
142                          qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 4000000000ULL);
143         }
144     }
145 }
146 
extern_timeout(void * opaque)147 static void extern_timeout(void *opaque)
148 {
149     IPMIBmcExtern *ibe = opaque;
150     IPMIInterface *s = ibe->parent.intf;
151 
152     if (ibe->connected) {
153         if (ibe->waiting_rsp && (ibe->outlen == 0)) {
154             IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
155             /* The message response timed out, return an error. */
156             ibe->waiting_rsp = false;
157             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
158             ibe->inbuf[2] = ibe->outbuf[2];
159             ibe->inbuf[3] = IPMI_CC_TIMEOUT;
160             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
161         } else {
162             continue_send(ibe);
163         }
164     }
165 }
166 
addchar(IPMIBmcExtern * ibe,unsigned char ch)167 static void addchar(IPMIBmcExtern *ibe, unsigned char ch)
168 {
169     switch (ch) {
170     case VM_MSG_CHAR:
171     case VM_CMD_CHAR:
172     case VM_ESCAPE_CHAR:
173         ibe->outbuf[ibe->outlen] = VM_ESCAPE_CHAR;
174         ibe->outlen++;
175         ch |= 0x10;
176         /* fall through */
177     default:
178         ibe->outbuf[ibe->outlen] = ch;
179         ibe->outlen++;
180     }
181 }
182 
ipmi_bmc_extern_handle_command(IPMIBmc * b,uint8_t * cmd,unsigned int cmd_len,unsigned int max_cmd_len,uint8_t msg_id)183 static void ipmi_bmc_extern_handle_command(IPMIBmc *b,
184                                        uint8_t *cmd, unsigned int cmd_len,
185                                        unsigned int max_cmd_len,
186                                        uint8_t msg_id)
187 {
188     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
189     IPMIInterface *s = ibe->parent.intf;
190     uint8_t err = 0, csum;
191     unsigned int i;
192 
193     if (ibe->outlen) {
194         /* We already have a command queued.  Shouldn't ever happen. */
195         error_report("IPMI KCS: Got command when not finished with the"
196                      " previous command");
197         abort();
198     }
199 
200     /* If it's too short or it was truncated, return an error. */
201     if (cmd_len < 2) {
202         err = IPMI_CC_REQUEST_DATA_LENGTH_INVALID;
203     } else if ((cmd_len > max_cmd_len) || (cmd_len > MAX_IPMI_MSG_SIZE)) {
204         err = IPMI_CC_REQUEST_DATA_TRUNCATED;
205     } else if (!ibe->connected) {
206         err = IPMI_CC_BMC_INIT_IN_PROGRESS;
207     }
208     if (err) {
209         IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
210         unsigned char rsp[3];
211         rsp[0] = cmd[0] | 0x04;
212         rsp[1] = cmd[1];
213         rsp[2] = err;
214         ibe->waiting_rsp = false;
215         k->handle_rsp(s, msg_id, rsp, 3);
216         return;
217     }
218 
219     addchar(ibe, msg_id);
220     for (i = 0; i < cmd_len; i++) {
221         addchar(ibe, cmd[i]);
222     }
223     csum = ipmb_checksum(&msg_id, 1, 0);
224     addchar(ibe, -ipmb_checksum(cmd, cmd_len, csum));
225 
226     ibe->outbuf[ibe->outlen] = VM_MSG_CHAR;
227     ibe->outlen++;
228 
229     /* Start the transmit */
230     continue_send(ibe);
231 }
232 
handle_hw_op(IPMIBmcExtern * ibe,unsigned char hw_op)233 static void handle_hw_op(IPMIBmcExtern *ibe, unsigned char hw_op)
234 {
235     IPMIInterface *s = ibe->parent.intf;
236     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
237 
238     switch (hw_op) {
239     case VM_CMD_VERSION:
240         /* We only support one version at this time. */
241         break;
242 
243     case VM_CMD_NOATTN:
244         k->set_atn(s, 0, 0);
245         break;
246 
247     case VM_CMD_ATTN:
248         k->set_atn(s, 1, 0);
249         break;
250 
251     case VM_CMD_ATTN_IRQ:
252         k->set_atn(s, 1, 1);
253         break;
254 
255     case VM_CMD_POWEROFF:
256         k->do_hw_op(s, IPMI_POWEROFF_CHASSIS, 0);
257         break;
258 
259     case VM_CMD_RESET:
260         k->do_hw_op(s, IPMI_RESET_CHASSIS, 0);
261         break;
262 
263     case VM_CMD_ENABLE_IRQ:
264         k->set_irq_enable(s, 1);
265         break;
266 
267     case VM_CMD_DISABLE_IRQ:
268         k->set_irq_enable(s, 0);
269         break;
270 
271     case VM_CMD_SEND_NMI:
272         k->do_hw_op(s, IPMI_SEND_NMI, 0);
273         break;
274 
275     case VM_CMD_GRACEFUL_SHUTDOWN:
276         k->do_hw_op(s, IPMI_SHUTDOWN_VIA_ACPI_OVERTEMP, 0);
277         break;
278     }
279 }
280 
handle_msg(IPMIBmcExtern * ibe)281 static void handle_msg(IPMIBmcExtern *ibe)
282 {
283     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(ibe->parent.intf);
284 
285     if (ibe->in_escape) {
286         ipmi_debug("msg escape not ended\n");
287         return;
288     }
289     if (ibe->inpos < 5) {
290         ipmi_debug("msg too short\n");
291         return;
292     }
293     if (ibe->in_too_many) {
294         ibe->inbuf[3] = IPMI_CC_REQUEST_DATA_TRUNCATED;
295         ibe->inpos = 4;
296     } else if (ipmb_checksum(ibe->inbuf, ibe->inpos, 0) != 0) {
297         ipmi_debug("msg checksum failure\n");
298         return;
299     } else {
300         ibe->inpos--; /* Remove checksum */
301     }
302 
303     timer_del(ibe->extern_timer);
304     ibe->waiting_rsp = false;
305     k->handle_rsp(ibe->parent.intf, ibe->inbuf[0], ibe->inbuf + 1, ibe->inpos - 1);
306 }
307 
can_receive(void * opaque)308 static int can_receive(void *opaque)
309 {
310     return 1;
311 }
312 
receive(void * opaque,const uint8_t * buf,int size)313 static void receive(void *opaque, const uint8_t *buf, int size)
314 {
315     IPMIBmcExtern *ibe = opaque;
316     int i;
317     unsigned char hw_op;
318 
319     for (i = 0; i < size; i++) {
320         unsigned char ch = buf[i];
321 
322         switch (ch) {
323         case VM_MSG_CHAR:
324             handle_msg(ibe);
325             ibe->in_too_many = false;
326             ibe->inpos = 0;
327             break;
328 
329         case VM_CMD_CHAR:
330             if (ibe->in_too_many) {
331                 ipmi_debug("cmd in too many\n");
332                 ibe->in_too_many = false;
333                 ibe->inpos = 0;
334                 break;
335             }
336             if (ibe->in_escape) {
337                 ipmi_debug("cmd in escape\n");
338                 ibe->in_too_many = false;
339                 ibe->inpos = 0;
340                 ibe->in_escape = false;
341                 break;
342             }
343             ibe->in_too_many = false;
344             if (ibe->inpos < 1) {
345                 break;
346             }
347             hw_op = ibe->inbuf[0];
348             ibe->inpos = 0;
349             goto out_hw_op;
350             break;
351 
352         case VM_ESCAPE_CHAR:
353             ibe->in_escape = true;
354             break;
355 
356         default:
357             if (ibe->in_escape) {
358                 ch &= ~0x10;
359                 ibe->in_escape = false;
360             }
361             if (ibe->in_too_many) {
362                 break;
363             }
364             if (ibe->inpos >= sizeof(ibe->inbuf)) {
365                 ibe->in_too_many = true;
366                 break;
367             }
368             ibe->inbuf[ibe->inpos] = ch;
369             ibe->inpos++;
370             break;
371         }
372     }
373     return;
374 
375  out_hw_op:
376     handle_hw_op(ibe, hw_op);
377 }
378 
chr_event(void * opaque,QEMUChrEvent event)379 static void chr_event(void *opaque, QEMUChrEvent event)
380 {
381     IPMIBmcExtern *ibe = opaque;
382     IPMIInterface *s = ibe->parent.intf;
383     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
384     unsigned char v;
385 
386     switch (event) {
387     case CHR_EVENT_OPENED:
388         ibe->connected = true;
389         ibe->outpos = 0;
390         ibe->outlen = 0;
391         addchar(ibe, VM_CMD_VERSION);
392         addchar(ibe, VM_PROTOCOL_VERSION);
393         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
394         ibe->outlen++;
395         addchar(ibe, VM_CMD_CAPABILITIES);
396         v = VM_CAPABILITIES_IRQ | VM_CAPABILITIES_ATTN;
397         if (k->do_hw_op(ibe->parent.intf, IPMI_POWEROFF_CHASSIS, 1) == 0) {
398             v |= VM_CAPABILITIES_POWER;
399         }
400         if (k->do_hw_op(ibe->parent.intf, IPMI_SHUTDOWN_VIA_ACPI_OVERTEMP, 1)
401             == 0) {
402             v |= VM_CAPABILITIES_GRACEFUL_SHUTDOWN;
403         }
404         if (k->do_hw_op(ibe->parent.intf, IPMI_RESET_CHASSIS, 1) == 0) {
405             v |= VM_CAPABILITIES_RESET;
406         }
407         if (k->do_hw_op(ibe->parent.intf, IPMI_SEND_NMI, 1) == 0) {
408             v |= VM_CAPABILITIES_NMI;
409         }
410         addchar(ibe, v);
411         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
412         ibe->outlen++;
413         ibe->sending_cmd = false;
414         continue_send(ibe);
415         break;
416 
417     case CHR_EVENT_CLOSED:
418         if (!ibe->connected) {
419             return;
420         }
421         ibe->connected = false;
422         /*
423          * Don't hang the OS trying to handle the ATN bit, other end will
424          * resend on a reconnect.
425          */
426         k->set_atn(s, 0, 0);
427         if (ibe->waiting_rsp) {
428             ibe->waiting_rsp = false;
429             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
430             ibe->inbuf[2] = ibe->outbuf[2];
431             ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
432             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
433         }
434         break;
435 
436     case CHR_EVENT_BREAK:
437     case CHR_EVENT_MUX_IN:
438     case CHR_EVENT_MUX_OUT:
439         /* Ignore */
440         break;
441     }
442 }
443 
ipmi_bmc_extern_handle_reset(IPMIBmc * b)444 static void ipmi_bmc_extern_handle_reset(IPMIBmc *b)
445 {
446     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
447 
448     ibe->send_reset = true;
449     continue_send(ibe);
450 }
451 
ipmi_bmc_extern_post_migrate(void * opaque,int version_id)452 static int ipmi_bmc_extern_post_migrate(void *opaque, int version_id)
453 {
454     IPMIBmcExtern *ibe = opaque;
455 
456     /*
457      * We don't directly restore waiting_rsp, Instead, we return an
458      * error on the interface if a response was being waited for.
459      */
460     if (ibe->waiting_rsp) {
461         IPMIInterface *ii = ibe->parent.intf;
462         IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
463 
464         ibe->waiting_rsp = false;
465         ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
466         ibe->inbuf[2] = ibe->outbuf[2];
467         ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
468         iic->handle_rsp(ii, ibe->outbuf[0], ibe->inbuf + 1, 3);
469     }
470     return 0;
471 }
472 
473 static const VMStateDescription vmstate_ipmi_bmc_extern = {
474     .name = TYPE_IPMI_BMC_EXTERN,
475     .version_id = 1,
476     .minimum_version_id = 1,
477     .post_load = ipmi_bmc_extern_post_migrate,
478     .fields = (const VMStateField[]) {
479         VMSTATE_BOOL(send_reset, IPMIBmcExtern),
480         VMSTATE_BOOL(waiting_rsp, IPMIBmcExtern),
481         VMSTATE_END_OF_LIST()
482     }
483 };
484 
ipmi_bmc_extern_realize(DeviceState * dev,Error ** errp)485 static void ipmi_bmc_extern_realize(DeviceState *dev, Error **errp)
486 {
487     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(dev);
488 
489     if (!qemu_chr_fe_backend_connected(&ibe->chr)) {
490         error_setg(errp, "IPMI external bmc requires chardev attribute");
491         return;
492     }
493 
494     qemu_chr_fe_set_handlers(&ibe->chr, can_receive, receive,
495                              chr_event, NULL, ibe, NULL, true);
496 }
497 
ipmi_bmc_extern_init(Object * obj)498 static void ipmi_bmc_extern_init(Object *obj)
499 {
500     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
501 
502     ibe->extern_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, extern_timeout, ibe);
503 }
504 
ipmi_bmc_extern_finalize(Object * obj)505 static void ipmi_bmc_extern_finalize(Object *obj)
506 {
507     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
508 
509     timer_free(ibe->extern_timer);
510 }
511 
512 static const Property ipmi_bmc_extern_properties[] = {
513     DEFINE_PROP_CHR("chardev", IPMIBmcExtern, chr),
514 };
515 
ipmi_bmc_extern_class_init(ObjectClass * oc,const void * data)516 static void ipmi_bmc_extern_class_init(ObjectClass *oc, const void *data)
517 {
518     DeviceClass *dc = DEVICE_CLASS(oc);
519     IPMIBmcClass *bk = IPMI_BMC_CLASS(oc);
520 
521     bk->handle_command = ipmi_bmc_extern_handle_command;
522     bk->handle_reset = ipmi_bmc_extern_handle_reset;
523     dc->hotpluggable = false;
524     dc->realize = ipmi_bmc_extern_realize;
525     dc->vmsd = &vmstate_ipmi_bmc_extern;
526     device_class_set_props(dc, ipmi_bmc_extern_properties);
527 }
528 
529 static const TypeInfo ipmi_bmc_extern_type = {
530     .name          = TYPE_IPMI_BMC_EXTERN,
531     .parent        = TYPE_IPMI_BMC,
532     .instance_size = sizeof(IPMIBmcExtern),
533     .instance_init = ipmi_bmc_extern_init,
534     .instance_finalize = ipmi_bmc_extern_finalize,
535     .class_init    = ipmi_bmc_extern_class_init,
536  };
537 
ipmi_bmc_extern_register_types(void)538 static void ipmi_bmc_extern_register_types(void)
539 {
540     type_register_static(&ipmi_bmc_extern_type);
541 }
542 
543 type_init(ipmi_bmc_extern_register_types)
544