xref: /openbmc/linux/drivers/platform/x86/intel/ifs/load.c (revision f845af67)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2022 Intel Corporation. */
3 
4 #include <linux/firmware.h>
5 #include <asm/cpu.h>
6 #include <asm/microcode.h>
7 
8 #include "ifs.h"
9 
10 #define IFS_CHUNK_ALIGNMENT	256
11 union meta_data {
12 	struct {
13 		u32 meta_type;		// metadata type
14 		u32 meta_size;		// size of this entire struct including hdrs.
15 		u32 test_type;		// IFS test type
16 		u32 fusa_info;		// Fusa info
17 		u32 total_images;	// Total number of images
18 		u32 current_image;	// Current Image #
19 		u32 total_chunks;	// Total number of chunks in this image
20 		u32 starting_chunk;	// Starting chunk number in this image
21 		u32 size_per_chunk;	// size of each chunk
22 		u32 chunks_per_stride;	// number of chunks in a stride
23 	};
24 	u8 padding[IFS_CHUNK_ALIGNMENT];
25 };
26 
27 #define IFS_HEADER_SIZE	(sizeof(struct microcode_header_intel))
28 #define META_TYPE_IFS	1
29 static  struct microcode_header_intel *ifs_header_ptr;	/* pointer to the ifs image header */
30 static u64 ifs_hash_ptr;			/* Address of ifs metadata (hash) */
31 static u64 ifs_test_image_ptr;			/* 256B aligned address of test pattern */
32 static DECLARE_COMPLETION(ifs_done);
33 
34 static const char * const scan_hash_status[] = {
35 	[0] = "No error reported",
36 	[1] = "Attempt to copy scan hashes when copy already in progress",
37 	[2] = "Secure Memory not set up correctly",
38 	[3] = "FuSaInfo.ProgramID does not match or ff-mm-ss does not match",
39 	[4] = "Reserved",
40 	[5] = "Integrity check failed",
41 	[6] = "Scan reload or test is in progress"
42 };
43 
44 static const char * const scan_authentication_status[] = {
45 	[0] = "No error reported",
46 	[1] = "Attempt to authenticate a chunk which is already marked as authentic",
47 	[2] = "Chunk authentication error. The hash of chunk did not match expected value"
48 };
49 
50 #define MC_HEADER_META_TYPE_END		(0)
51 
52 struct metadata_header {
53 	unsigned int		type;
54 	unsigned int		blk_size;
55 };
56 
57 static struct metadata_header *find_meta_data(void *ucode, unsigned int meta_type)
58 {
59 	struct microcode_header_intel *hdr = &((struct microcode_intel *)ucode)->hdr;
60 	struct metadata_header *meta_header;
61 	unsigned long data_size, total_meta;
62 	unsigned long meta_size = 0;
63 
64 	data_size = intel_microcode_get_datasize(hdr);
65 	total_meta = hdr->metasize;
66 	if (!total_meta)
67 		return NULL;
68 
69 	meta_header = (ucode + MC_HEADER_SIZE + data_size) - total_meta;
70 
71 	while (meta_header->type != MC_HEADER_META_TYPE_END &&
72 	       meta_header->blk_size &&
73 	       meta_size < total_meta) {
74 		meta_size += meta_header->blk_size;
75 		if (meta_header->type == meta_type)
76 			return meta_header;
77 
78 		meta_header = (void *)meta_header + meta_header->blk_size;
79 	}
80 	return NULL;
81 }
82 
83 /*
84  * To copy scan hashes and authenticate test chunks, the initiating cpu must point
85  * to the EDX:EAX to the test image in linear address.
86  * Run wrmsr(MSR_COPY_SCAN_HASHES) for scan hash copy and run wrmsr(MSR_AUTHENTICATE_AND_COPY_CHUNK)
87  * for scan hash copy and test chunk authentication.
88  */
89 static void copy_hashes_authenticate_chunks(struct work_struct *work)
90 {
91 	struct ifs_work *local_work = container_of(work, struct ifs_work, w);
92 	union ifs_scan_hashes_status hashes_status;
93 	union ifs_chunks_auth_status chunk_status;
94 	struct device *dev = local_work->dev;
95 	int i, num_chunks, chunk_size;
96 	struct ifs_data *ifsd;
97 	u64 linear_addr, base;
98 	u32 err_code;
99 
100 	ifsd = ifs_get_data(dev);
101 	/* run scan hash copy */
102 	wrmsrl(MSR_COPY_SCAN_HASHES, ifs_hash_ptr);
103 	rdmsrl(MSR_SCAN_HASHES_STATUS, hashes_status.data);
104 
105 	/* enumerate the scan image information */
106 	num_chunks = hashes_status.num_chunks;
107 	chunk_size = hashes_status.chunk_size * 1024;
108 	err_code = hashes_status.error_code;
109 
110 	if (!hashes_status.valid) {
111 		ifsd->loading_error = true;
112 		if (err_code >= ARRAY_SIZE(scan_hash_status)) {
113 			dev_err(dev, "invalid error code 0x%x for hash copy\n", err_code);
114 			goto done;
115 		}
116 		dev_err(dev, "Hash copy error : %s", scan_hash_status[err_code]);
117 		goto done;
118 	}
119 
120 	/* base linear address to the scan data */
121 	base = ifs_test_image_ptr;
122 
123 	/* scan data authentication and copy chunks to secured memory */
124 	for (i = 0; i < num_chunks; i++) {
125 		linear_addr = base + i * chunk_size;
126 		linear_addr |= i;
127 
128 		wrmsrl(MSR_AUTHENTICATE_AND_COPY_CHUNK, linear_addr);
129 		rdmsrl(MSR_CHUNKS_AUTHENTICATION_STATUS, chunk_status.data);
130 
131 		ifsd->valid_chunks = chunk_status.valid_chunks;
132 		err_code = chunk_status.error_code;
133 
134 		if (err_code) {
135 			ifsd->loading_error = true;
136 			if (err_code >= ARRAY_SIZE(scan_authentication_status)) {
137 				dev_err(dev,
138 					"invalid error code 0x%x for authentication\n", err_code);
139 				goto done;
140 			}
141 			dev_err(dev, "Chunk authentication error %s\n",
142 				scan_authentication_status[err_code]);
143 			goto done;
144 		}
145 	}
146 done:
147 	complete(&ifs_done);
148 }
149 
150 static int validate_ifs_metadata(struct device *dev)
151 {
152 	struct ifs_data *ifsd = ifs_get_data(dev);
153 	union meta_data *ifs_meta;
154 	char test_file[64];
155 	int ret = -EINVAL;
156 
157 	snprintf(test_file, sizeof(test_file), "%02x-%02x-%02x-%02x.scan",
158 		 boot_cpu_data.x86, boot_cpu_data.x86_model,
159 		 boot_cpu_data.x86_stepping, ifsd->cur_batch);
160 
161 	ifs_meta = (union meta_data *)find_meta_data(ifs_header_ptr, META_TYPE_IFS);
162 	if (!ifs_meta) {
163 		dev_err(dev, "IFS Metadata missing in file %s\n", test_file);
164 		return ret;
165 	}
166 
167 	ifs_test_image_ptr = (u64)ifs_meta + sizeof(union meta_data);
168 
169 	/* Scan chunk start must be 256 byte aligned */
170 	if (!IS_ALIGNED(ifs_test_image_ptr, IFS_CHUNK_ALIGNMENT)) {
171 		dev_err(dev, "Scan pattern is not aligned on %d bytes aligned in %s\n",
172 			IFS_CHUNK_ALIGNMENT, test_file);
173 		return ret;
174 	}
175 
176 	if (ifs_meta->current_image != ifsd->cur_batch) {
177 		dev_warn(dev, "Mismatch between filename %s and batch metadata 0x%02x\n",
178 			 test_file, ifs_meta->current_image);
179 		return ret;
180 	}
181 
182 	return 0;
183 }
184 
185 /*
186  * IFS requires scan chunks authenticated per each socket in the platform.
187  * Once the test chunk is authenticated, it is automatically copied to secured memory
188  * and proceed the authentication for the next chunk.
189  */
190 static int scan_chunks_sanity_check(struct device *dev)
191 {
192 	struct ifs_data *ifsd = ifs_get_data(dev);
193 	struct ifs_work local_work;
194 	int curr_pkg, cpu, ret;
195 
196 	memset(ifs_pkg_auth, 0, (topology_max_packages() * sizeof(bool)));
197 	ret = validate_ifs_metadata(dev);
198 	if (ret)
199 		return ret;
200 
201 	ifsd->loading_error = false;
202 	ifsd->loaded_version = ifs_header_ptr->rev;
203 
204 	/* copy the scan hash and authenticate per package */
205 	cpus_read_lock();
206 	for_each_online_cpu(cpu) {
207 		curr_pkg = topology_physical_package_id(cpu);
208 		if (ifs_pkg_auth[curr_pkg])
209 			continue;
210 		reinit_completion(&ifs_done);
211 		local_work.dev = dev;
212 		INIT_WORK_ONSTACK(&local_work.w, copy_hashes_authenticate_chunks);
213 		schedule_work_on(cpu, &local_work.w);
214 		wait_for_completion(&ifs_done);
215 		if (ifsd->loading_error) {
216 			ret = -EIO;
217 			goto out;
218 		}
219 		ifs_pkg_auth[curr_pkg] = 1;
220 	}
221 	ret = 0;
222 out:
223 	cpus_read_unlock();
224 
225 	return ret;
226 }
227 
228 static int image_sanity_check(struct device *dev, const struct microcode_header_intel *data)
229 {
230 	struct ucode_cpu_info uci;
231 
232 	/* Provide a specific error message when loading an older/unsupported image */
233 	if (data->hdrver != MC_HEADER_TYPE_IFS) {
234 		dev_err(dev, "Header version %d not supported\n", data->hdrver);
235 		return -EINVAL;
236 	}
237 
238 	if (intel_microcode_sanity_check((void *)data, true, MC_HEADER_TYPE_IFS)) {
239 		dev_err(dev, "sanity check failed\n");
240 		return -EINVAL;
241 	}
242 
243 	intel_cpu_collect_info(&uci);
244 
245 	if (!intel_find_matching_signature((void *)data,
246 					   uci.cpu_sig.sig,
247 					   uci.cpu_sig.pf)) {
248 		dev_err(dev, "cpu signature, processor flags not matching\n");
249 		return -EINVAL;
250 	}
251 
252 	return 0;
253 }
254 
255 /*
256  * Load ifs image. Before loading ifs module, the ifs image must be located
257  * in /lib/firmware/intel/ifs_x/ and named as family-model-stepping-02x.{testname}.
258  */
259 int ifs_load_firmware(struct device *dev)
260 {
261 	const struct ifs_test_caps *test = ifs_get_test_caps(dev);
262 	struct ifs_data *ifsd = ifs_get_data(dev);
263 	unsigned int expected_size;
264 	const struct firmware *fw;
265 	char scan_path[64];
266 	int ret = -EINVAL;
267 
268 	snprintf(scan_path, sizeof(scan_path), "intel/ifs_%d/%02x-%02x-%02x-%02x.scan",
269 		 test->test_num, boot_cpu_data.x86, boot_cpu_data.x86_model,
270 		 boot_cpu_data.x86_stepping, ifsd->cur_batch);
271 
272 	ret = request_firmware_direct(&fw, scan_path, dev);
273 	if (ret) {
274 		dev_err(dev, "ifs file %s load failed\n", scan_path);
275 		goto done;
276 	}
277 
278 	expected_size = ((struct microcode_header_intel *)fw->data)->totalsize;
279 	if (fw->size != expected_size) {
280 		dev_err(dev, "File size mismatch (expected %u, actual %zu). Corrupted IFS image.\n",
281 			expected_size, fw->size);
282 		return -EINVAL;
283 	}
284 
285 	ret = image_sanity_check(dev, (struct microcode_header_intel *)fw->data);
286 	if (ret)
287 		goto release;
288 
289 	ifs_header_ptr = (struct microcode_header_intel *)fw->data;
290 	ifs_hash_ptr = (u64)(ifs_header_ptr + 1);
291 
292 	ret = scan_chunks_sanity_check(dev);
293 	if (ret)
294 		dev_err(dev, "Load failure for batch: %02x\n", ifsd->cur_batch);
295 
296 release:
297 	release_firmware(fw);
298 done:
299 	ifsd->loaded = (ret == 0);
300 
301 	return ret;
302 }
303