1 /*
2 * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 */
19
20 FILE_LICENCE ( GPL2_OR_LATER );
21
22 /** @file
23 *
24 * VMware GuestInfo settings
25 *
26 */
27
28 #include <stdint.h>
29 #include <stdlib.h>
30 #include <stdio.h>
31 #include <string.h>
32 #include <errno.h>
33 #include <ipxe/init.h>
34 #include <ipxe/settings.h>
35 #include <ipxe/netdevice.h>
36 #include <ipxe/guestrpc.h>
37
38 /** GuestInfo GuestRPC channel */
39 static int guestinfo_channel;
40
41 /**
42 * Fetch value of typed GuestInfo setting
43 *
44 * @v settings Settings block
45 * @v setting Setting to fetch
46 * @v type Setting type to attempt (or NULL for default)
47 * @v data Buffer to fill with setting data
48 * @v len Length of buffer
49 * @ret found Setting found in GuestInfo
50 * @ret len Length of setting data, or negative error
51 */
guestinfo_fetch_type(struct settings * settings,struct setting * setting,const struct setting_type * type,void * data,size_t len,int * found)52 static int guestinfo_fetch_type ( struct settings *settings,
53 struct setting *setting,
54 const struct setting_type *type,
55 void *data, size_t len, int *found ) {
56 const char *parent_name = settings->parent->name;
57 char command[ 24 /* "info-get guestinfo.ipxe." */ +
58 strlen ( parent_name ) + 1 /* "." */ +
59 strlen ( setting->name ) + 1 /* "." */ +
60 ( type ? strlen ( type->name ) : 0 ) + 1 /* NUL */ ];
61 struct setting *predefined;
62 char *info;
63 int info_len;
64 int check_len;
65 int ret;
66
67 /* Construct info-get command */
68 snprintf ( command, sizeof ( command ),
69 "info-get guestinfo.ipxe.%s%s%s%s%s",
70 parent_name, ( parent_name[0] ? "." : "" ), setting->name,
71 ( type ? "." : "" ), ( type ? type->name : "" ) );
72
73 /* Check for existence and obtain length of GuestInfo value */
74 info_len = guestrpc_command ( guestinfo_channel, command, NULL, 0 );
75 if ( info_len < 0 ) {
76 ret = info_len;
77 goto err_get_info_len;
78 }
79
80 /* Mark as found */
81 *found = 1;
82
83 /* Determine default type if necessary */
84 if ( ! type ) {
85 predefined = find_setting ( setting->name );
86 type = ( predefined ? predefined->type : &setting_type_string );
87 }
88 assert ( type != NULL );
89
90 /* Allocate temporary block to hold GuestInfo value */
91 info = zalloc ( info_len + 1 /* NUL */ );
92 if ( ! info ) {
93 DBGC ( settings, "GuestInfo %p could not allocate %d bytes\n",
94 settings, info_len );
95 ret = -ENOMEM;
96 goto err_alloc;
97 }
98 info[info_len] = '\0';
99
100 /* Fetch GuestInfo value */
101 check_len = guestrpc_command ( guestinfo_channel, command,
102 info, info_len );
103 if ( check_len < 0 ) {
104 ret = check_len;
105 goto err_get_info;
106 }
107 if ( check_len != info_len ) {
108 DBGC ( settings, "GuestInfo %p length mismatch (expected %d, "
109 "got %d)\n", settings, info_len, check_len );
110 ret = -EIO;
111 goto err_get_info;
112 }
113 DBGC2 ( settings, "GuestInfo %p found %s = \"%s\"\n",
114 settings, &command[9] /* Skip "info-get " */, info );
115
116 /* Parse GuestInfo value according to type */
117 ret = setting_parse ( type, info, data, len );
118 if ( ret < 0 ) {
119 DBGC ( settings, "GuestInfo %p could not parse \"%s\" as %s: "
120 "%s\n", settings, info, type->name, strerror ( ret ) );
121 goto err_parse;
122 }
123
124 err_parse:
125 err_get_info:
126 free ( info );
127 err_alloc:
128 err_get_info_len:
129 return ret;
130 }
131
132 /**
133 * Fetch value of GuestInfo setting
134 *
135 * @v settings Settings block
136 * @v setting Setting to fetch
137 * @v data Buffer to fill with setting data
138 * @v len Length of buffer
139 * @ret len Length of setting data, or negative error
140 */
guestinfo_fetch(struct settings * settings,struct setting * setting,void * data,size_t len)141 static int guestinfo_fetch ( struct settings *settings,
142 struct setting *setting,
143 void *data, size_t len ) {
144 struct setting_type *type;
145 int found = 0;
146 int ret;
147
148 /* Try default type first */
149 ret = guestinfo_fetch_type ( settings, setting, NULL,
150 data, len, &found );
151 if ( found )
152 return ret;
153
154 /* Otherwise, try all possible types */
155 for_each_table_entry ( type, SETTING_TYPES ) {
156 ret = guestinfo_fetch_type ( settings, setting, type,
157 data, len, &found );
158 if ( found )
159 return ret;
160 }
161
162 /* Not found */
163 return -ENOENT;
164 }
165
166 /** GuestInfo settings operations */
167 static struct settings_operations guestinfo_settings_operations = {
168 .fetch = guestinfo_fetch,
169 };
170
171 /** GuestInfo settings */
172 static struct settings guestinfo_settings = {
173 .refcnt = NULL,
174 .siblings = LIST_HEAD_INIT ( guestinfo_settings.siblings ),
175 .children = LIST_HEAD_INIT ( guestinfo_settings.children ),
176 .op = &guestinfo_settings_operations,
177 };
178
179 /** Initialise GuestInfo settings */
guestinfo_init(void)180 static void guestinfo_init ( void ) {
181 int rc;
182
183 /* Open GuestRPC channel */
184 guestinfo_channel = guestrpc_open();
185 if ( guestinfo_channel < 0 ) {
186 rc = guestinfo_channel;
187 DBG ( "GuestInfo could not open channel: %s\n",
188 strerror ( rc ) );
189 return;
190 }
191
192 /* Register root GuestInfo settings */
193 if ( ( rc = register_settings ( &guestinfo_settings, NULL,
194 "vmware" ) ) != 0 ) {
195 DBG ( "GuestInfo could not register settings: %s\n",
196 strerror ( rc ) );
197 return;
198 }
199 }
200
201 /** GuestInfo settings initialiser */
202 struct init_fn guestinfo_init_fn __init_fn ( INIT_NORMAL ) = {
203 .initialise = guestinfo_init,
204 };
205
206 /**
207 * Create per-netdevice GuestInfo settings
208 *
209 * @v netdev Network device
210 * @ret rc Return status code
211 */
guestinfo_net_probe(struct net_device * netdev)212 static int guestinfo_net_probe ( struct net_device *netdev ) {
213 struct settings *settings;
214 int rc;
215
216 /* Do nothing unless we have a GuestInfo channel available */
217 if ( guestinfo_channel < 0 )
218 return 0;
219
220 /* Allocate and initialise settings block */
221 settings = zalloc ( sizeof ( *settings ) );
222 if ( ! settings ) {
223 rc = -ENOMEM;
224 goto err_alloc;
225 }
226 settings_init ( settings, &guestinfo_settings_operations, NULL, NULL );
227
228 /* Register settings */
229 if ( ( rc = register_settings ( settings, netdev_settings ( netdev ),
230 "vmware" ) ) != 0 ) {
231 DBGC ( settings, "GuestInfo %p could not register for %s: %s\n",
232 settings, netdev->name, strerror ( rc ) );
233 goto err_register;
234 }
235 DBGC ( settings, "GuestInfo %p registered for %s\n",
236 settings, netdev->name );
237
238 return 0;
239
240 err_register:
241 free ( settings );
242 err_alloc:
243 return rc;
244 }
245
246 /**
247 * Remove per-netdevice GuestInfo settings
248 *
249 * @v netdev Network device
250 */
guestinfo_net_remove(struct net_device * netdev)251 static void guestinfo_net_remove ( struct net_device *netdev ) {
252 struct settings *parent = netdev_settings ( netdev );
253 struct settings *settings;
254
255 list_for_each_entry ( settings, &parent->children, siblings ) {
256 if ( settings->op == &guestinfo_settings_operations ) {
257 DBGC ( settings, "GuestInfo %p unregistered for %s\n",
258 settings, netdev->name );
259 unregister_settings ( settings );
260 free ( settings );
261 return;
262 }
263 }
264 }
265
266 /** GuestInfo per-netdevice driver */
267 struct net_driver guestinfo_net_driver __net_driver = {
268 .name = "GuestInfo",
269 .probe = guestinfo_net_probe,
270 .remove = guestinfo_net_remove,
271 };
272