Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2021-09-25-v2' into staging
[qemu.git] / net / announce.c
1 /*
2 * Self-announce
3 * (c) 2017-2019 Red Hat, Inc.
4 *
5 * This work is licensed under the terms of the GNU GPL, version 2 or later.
6 * See the COPYING file in the top-level directory.
7 */
8
9 #include "qemu/osdep.h"
10 #include "qemu-common.h"
11 #include "net/announce.h"
12 #include "net/net.h"
13 #include "qapi/clone-visitor.h"
14 #include "qapi/qapi-visit-net.h"
15 #include "qapi/qapi-commands-net.h"
16 #include "trace.h"
17
18 static GData *named_timers;
19
20 int64_t qemu_announce_timer_step(AnnounceTimer *timer)
21 {
22 int64_t step;
23
24 step = timer->params.initial +
25 (timer->params.rounds - timer->round - 1) *
26 timer->params.step;
27
28 if (step < 0 || step > timer->params.max) {
29 step = timer->params.max;
30 }
31 timer_mod(timer->tm, qemu_clock_get_ms(timer->type) + step);
32
33 return step;
34 }
35
36 /*
37 * If 'free_named' is true, then remove the timer from the list
38 * and free the timer itself.
39 */
40 void qemu_announce_timer_del(AnnounceTimer *timer, bool free_named)
41 {
42 bool free_timer = false;
43 if (timer->tm) {
44 timer_free(timer->tm);
45 timer->tm = NULL;
46 }
47 qapi_free_strList(timer->params.interfaces);
48 timer->params.interfaces = NULL;
49 if (free_named && timer->params.has_id) {
50 AnnounceTimer *list_timer;
51 /*
52 * Sanity check: There should only be one timer on the list with
53 * the id.
54 */
55 list_timer = g_datalist_get_data(&named_timers, timer->params.id);
56 assert(timer == list_timer);
57 free_timer = true;
58 g_datalist_remove_data(&named_timers, timer->params.id);
59 }
60 trace_qemu_announce_timer_del(free_named, free_timer, timer->params.id);
61 g_free(timer->params.id);
62 timer->params.id = NULL;
63
64 if (free_timer) {
65 g_free(timer);
66 }
67 }
68
69 /*
70 * Under BQL/main thread
71 * Reset the timer to the given parameters/type/notifier.
72 */
73 void qemu_announce_timer_reset(AnnounceTimer *timer,
74 AnnounceParameters *params,
75 QEMUClockType type,
76 QEMUTimerCB *cb,
77 void *opaque)
78 {
79 /*
80 * We're under the BQL, so the current timer can't
81 * be firing, so we should be able to delete it.
82 */
83 qemu_announce_timer_del(timer, false);
84
85 QAPI_CLONE_MEMBERS(AnnounceParameters, &timer->params, params);
86 timer->round = params->rounds;
87 timer->type = type;
88 timer->tm = timer_new_ms(type, cb, opaque);
89 }
90
91 #ifndef ETH_P_RARP
92 #define ETH_P_RARP 0x8035
93 #endif
94 #define ARP_HTYPE_ETH 0x0001
95 #define ARP_PTYPE_IP 0x0800
96 #define ARP_OP_REQUEST_REV 0x3
97
98 static int announce_self_create(uint8_t *buf,
99 uint8_t *mac_addr)
100 {
101 /* Ethernet header. */
102 memset(buf, 0xff, 6); /* destination MAC addr */
103 memcpy(buf + 6, mac_addr, 6); /* source MAC addr */
104 *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */
105
106 /* RARP header. */
107 *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */
108 *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */
109 *(buf + 18) = 6; /* hardware addr length (ethernet) */
110 *(buf + 19) = 4; /* protocol addr length (IPv4) */
111 *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */
112 memcpy(buf + 22, mac_addr, 6); /* source hw addr */
113 memset(buf + 28, 0x00, 4); /* source protocol addr */
114 memcpy(buf + 32, mac_addr, 6); /* target hw addr */
115 memset(buf + 38, 0x00, 4); /* target protocol addr */
116
117 /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */
118 memset(buf + 42, 0x00, 18);
119
120 return 60; /* len (FCS will be added by hardware) */
121 }
122
123 static void qemu_announce_self_iter(NICState *nic, void *opaque)
124 {
125 AnnounceTimer *timer = opaque;
126 uint8_t buf[60];
127 int len;
128 bool skip;
129
130 if (timer->params.has_interfaces) {
131 strList *entry = timer->params.interfaces;
132 /* Skip unless we find our name in the requested list */
133 skip = true;
134
135 while (entry) {
136 if (!strcmp(entry->value, nic->ncs->name)) {
137 /* Found us */
138 skip = false;
139 break;
140 }
141 entry = entry->next;
142 }
143 } else {
144 skip = false;
145 }
146
147 trace_qemu_announce_self_iter(timer->params.has_id ? timer->params.id : "_",
148 nic->ncs->name,
149 qemu_ether_ntoa(&nic->conf->macaddr), skip);
150
151 if (!skip) {
152 len = announce_self_create(buf, nic->conf->macaddr.a);
153
154 qemu_send_packet_raw(qemu_get_queue(nic), buf, len);
155
156 /* if the NIC provides it's own announcement support, use it as well */
157 if (nic->ncs->info->announce) {
158 nic->ncs->info->announce(nic->ncs);
159 }
160 }
161 }
162 static void qemu_announce_self_once(void *opaque)
163 {
164 AnnounceTimer *timer = (AnnounceTimer *)opaque;
165
166 qemu_foreach_nic(qemu_announce_self_iter, timer);
167
168 if (--timer->round) {
169 qemu_announce_timer_step(timer);
170 } else {
171 qemu_announce_timer_del(timer, true);
172 }
173 }
174
175 void qemu_announce_self(AnnounceTimer *timer, AnnounceParameters *params)
176 {
177 qemu_announce_timer_reset(timer, params, QEMU_CLOCK_REALTIME,
178 qemu_announce_self_once, timer);
179 if (params->rounds) {
180 qemu_announce_self_once(timer);
181 } else {
182 qemu_announce_timer_del(timer, true);
183 }
184 }
185
186 void qmp_announce_self(AnnounceParameters *params, Error **errp)
187 {
188 AnnounceTimer *named_timer;
189 if (!params->has_id) {
190 params->id = g_strdup("");
191 params->has_id = true;
192 }
193
194 named_timer = g_datalist_get_data(&named_timers, params->id);
195
196 if (!named_timer) {
197 named_timer = g_new0(AnnounceTimer, 1);
198 g_datalist_set_data(&named_timers, params->id, named_timer);
199 }
200
201 qemu_announce_self(named_timer, params);
202 }