1 /*
2  * Copyright (C) 2019 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_OR_UBDL );
21 
22 #include <stddef.h>
23 #include <string.h>
24 #include <errno.h>
25 #include <ipxe/settings.h>
26 #include <ipxe/efi/efi.h>
27 #include <ipxe/efi/Protocol/DriverBinding.h>
28 #include <ipxe/efi/Protocol/LoadedImage.h>
29 #include <ipxe/efi/Protocol/ComponentName.h>
30 #include <ipxe/efi/efi_blacklist.h>
31 
32 /** @file
33  *
34  * EFI driver blacklist
35  *
36  */
37 
38 /** A blacklisted driver */
39 struct efi_blacklist {
40 	/** Name */
41 	const char *name;
42 	/**
43 	 * Check if driver is blacklisted
44 	 *
45 	 * @v binding		Driver binding protocol
46 	 * @v loaded		Loaded image protocol
47 	 * @v wtf		Component name protocol, if present
48 	 * @ret blacklisted	Driver is the blacklisted driver
49 	 */
50 	int ( * blacklist ) ( EFI_DRIVER_BINDING_PROTOCOL *binding,
51 			      EFI_LOADED_IMAGE_PROTOCOL *loaded,
52 			      EFI_COMPONENT_NAME_PROTOCOL *wtf );
53 };
54 
55 /**
56  * Blacklist Dell Ip4ConfigDxe driver
57  *
58  * @v binding		Driver binding protocol
59  * @v loaded		Loaded image protocol
60  * @v wtf		Component name protocol, if present
61  * @ret blacklisted	Driver is the blacklisted driver
62  */
63 static int
efi_blacklist_dell_ip4config(EFI_DRIVER_BINDING_PROTOCOL * binding __unused,EFI_LOADED_IMAGE_PROTOCOL * loaded __unused,EFI_COMPONENT_NAME_PROTOCOL * wtf)64 efi_blacklist_dell_ip4config ( EFI_DRIVER_BINDING_PROTOCOL *binding __unused,
65 			       EFI_LOADED_IMAGE_PROTOCOL *loaded __unused,
66 			       EFI_COMPONENT_NAME_PROTOCOL *wtf ) {
67 	static const CHAR16 ip4cfg[] = L"IP4 CONFIG Network Service Driver";
68 	static const char dell[] = "Dell Inc.";
69 	char manufacturer[ sizeof ( dell ) ];
70 	CHAR16 *name;
71 
72 	/* Check driver name */
73 	if ( ! wtf )
74 		return 0;
75 	if ( wtf->GetDriverName ( wtf, "eng", &name ) != 0 )
76 		return 0;
77 	if ( memcmp ( name, ip4cfg, sizeof ( ip4cfg ) ) != 0 )
78 		return 0;
79 
80 	/* Check manufacturer */
81 	fetch_string_setting ( NULL, &manufacturer_setting, manufacturer,
82 			       sizeof ( manufacturer ) );
83 	if ( strcmp ( manufacturer, dell ) != 0 )
84 		return 0;
85 
86 	return 1;
87 }
88 
89 /** Blacklisted drivers */
90 static struct efi_blacklist efi_blacklists[] = {
91 	{
92 		.name = "Dell Ip4Config",
93 		.blacklist = efi_blacklist_dell_ip4config,
94 	},
95 };
96 
97 /**
98  * Find driver blacklisting, if any
99  *
100  * @v driver		Driver binding handle
101  * @ret blacklist	Driver blacklisting, or NULL
102  * @ret rc		Return status code
103  */
efi_blacklist(EFI_HANDLE driver,struct efi_blacklist ** blacklist)104 static int efi_blacklist ( EFI_HANDLE driver,
105 			   struct efi_blacklist **blacklist ) {
106 	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
107 	union {
108 		EFI_DRIVER_BINDING_PROTOCOL *binding;
109 		void *interface;
110 	} binding;
111 	union {
112 		EFI_LOADED_IMAGE_PROTOCOL *loaded;
113 		void *interface;
114 	} loaded;
115 	union {
116 		EFI_COMPONENT_NAME_PROTOCOL *wtf;
117 		void *interface;
118 	} wtf;
119 	unsigned int i;
120 	EFI_HANDLE image;
121 	EFI_STATUS efirc;
122 	int rc;
123 
124 	DBGC2 ( &efi_blacklists, "EFIBL checking %s\n",
125 		efi_handle_name ( driver ) );
126 
127 	/* Mark as not blacklisted */
128 	*blacklist = NULL;
129 
130 	/* Open driver binding protocol */
131 	if ( ( efirc = bs->OpenProtocol (
132 			driver, &efi_driver_binding_protocol_guid,
133 			&binding.interface, efi_image_handle, driver,
134 			EFI_OPEN_PROTOCOL_GET_PROTOCOL ) ) != 0 ) {
135 		rc = -EEFI ( efirc );
136 		DBGC ( driver, "EFIBL %s could not open driver binding "
137 		       "protocol: %s\n", efi_handle_name ( driver ),
138 		       strerror ( rc ) );
139 		goto err_binding;
140 	}
141 	image = binding.binding->ImageHandle;
142 
143 	/* Open loaded image protocol */
144 	if ( ( efirc = bs->OpenProtocol (
145 			image, &efi_loaded_image_protocol_guid,
146 			&loaded.interface, efi_image_handle, image,
147 			EFI_OPEN_PROTOCOL_GET_PROTOCOL ) ) != 0 ) {
148 		rc = -EEFI ( efirc );
149 		DBGC ( driver, "EFIBL %s could not open",
150 		       efi_handle_name ( driver ) );
151 		DBGC ( driver, " %s loaded image protocol: %s\n",
152 		       efi_handle_name ( image ), strerror ( rc ) );
153 		goto err_loaded;
154 	}
155 
156 	/* Open component name protocol, if present*/
157 	if ( ( efirc = bs->OpenProtocol (
158 			driver, &efi_component_name_protocol_guid,
159 			&wtf.interface, efi_image_handle, driver,
160 			EFI_OPEN_PROTOCOL_GET_PROTOCOL ) ) != 0 ) {
161 		/* Ignore failure; is not required to be present */
162 		wtf.interface = NULL;
163 	}
164 
165 	/* Check blacklistings */
166 	for ( i = 0 ; i < ( sizeof ( efi_blacklists ) /
167 			    sizeof ( efi_blacklists[0] ) ) ; i++ ) {
168 		if ( efi_blacklists[i].blacklist ( binding.binding,
169 						   loaded.loaded, wtf.wtf ) ) {
170 			*blacklist = &efi_blacklists[i];
171 			break;
172 		}
173 	}
174 
175 	/* Success */
176 	rc = 0;
177 
178 	/* Close protocols */
179 	if ( wtf.wtf ) {
180 		bs->CloseProtocol ( driver, &efi_component_name_protocol_guid,
181 				    efi_image_handle, driver );
182 	}
183 	bs->CloseProtocol ( image, &efi_loaded_image_protocol_guid,
184 			    efi_image_handle, image );
185  err_loaded:
186 	bs->CloseProtocol ( driver, &efi_driver_binding_protocol_guid,
187 			    efi_image_handle, driver );
188  err_binding:
189 	return rc;
190 }
191 
192 /**
193  * Unload any blacklisted drivers
194  *
195  */
efi_unload_blacklist(void)196 void efi_unload_blacklist ( void ) {
197 	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
198 	struct efi_blacklist *blacklist;
199 	EFI_HANDLE *drivers;
200 	EFI_HANDLE driver;
201 	UINTN num_drivers;
202 	unsigned int i;
203 	EFI_STATUS efirc;
204 	int rc;
205 
206 	/* Locate all driver binding protocol handles */
207 	if ( ( efirc = bs->LocateHandleBuffer (
208 			ByProtocol, &efi_driver_binding_protocol_guid,
209 			NULL, &num_drivers, &drivers ) ) != 0 ) {
210 		rc = -EEFI ( efirc );
211 		DBGC ( &efi_blacklists, "EFIBL could not list all drivers: "
212 		       "%s\n", strerror ( rc ) );
213 		return;
214 	}
215 
216 	/* Unload any blacklisted drivers */
217 	for ( i = 0 ; i < num_drivers ; i++ ) {
218 		driver = drivers[i];
219 		if ( ( rc = efi_blacklist ( driver, &blacklist ) ) != 0 ) {
220 			DBGC ( driver, "EFIBL could not determine "
221 			       "blacklisting for %s: %s\n",
222 			       efi_handle_name ( driver ), strerror ( rc ) );
223 			continue;
224 		}
225 		if ( ! blacklist )
226 			continue;
227 		DBGC ( driver, "EFIBL unloading %s (%s)\n",
228 		       efi_handle_name ( driver ), blacklist->name );
229 		if ( ( efirc = bs->UnloadImage ( driver ) ) != 0 ) {
230 			DBGC ( driver, "EFIBL could not unload %s: %s\n",
231 			       efi_handle_name ( driver ), strerror ( rc ) );
232 		}
233 	}
234 
235 	/* Free handle list */
236 	bs->FreePool ( drivers );
237 }
238