1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 Politecnico di Torino, Italy
4  *                    TORSEC group -- https://security.polito.it
5  *
6  * Author: Roberto Sassu <roberto.sassu@polito.it>
7  *
8  * File: ima_template_lib.c
9  *      Library of supported template fields.
10  */
11 
12 #include "ima_template_lib.h"
13 #include <linux/xattr.h>
14 #include <linux/evm.h>
15 
ima_template_hash_algo_allowed(u8 algo)16 static bool ima_template_hash_algo_allowed(u8 algo)
17 {
18 	if (algo == HASH_ALGO_SHA1 || algo == HASH_ALGO_MD5)
19 		return true;
20 
21 	return false;
22 }
23 
24 enum data_formats {
25 	DATA_FMT_DIGEST = 0,
26 	DATA_FMT_DIGEST_WITH_ALGO,
27 	DATA_FMT_DIGEST_WITH_TYPE_AND_ALGO,
28 	DATA_FMT_STRING,
29 	DATA_FMT_HEX,
30 	DATA_FMT_UINT
31 };
32 
33 enum digest_type {
34 	DIGEST_TYPE_IMA,
35 	DIGEST_TYPE_VERITY,
36 	DIGEST_TYPE__LAST
37 };
38 
39 #define DIGEST_TYPE_NAME_LEN_MAX 7	/* including NUL */
40 static const char * const digest_type_name[DIGEST_TYPE__LAST] = {
41 	[DIGEST_TYPE_IMA] = "ima",
42 	[DIGEST_TYPE_VERITY] = "verity"
43 };
44 
ima_write_template_field_data(const void * data,const u32 datalen,enum data_formats datafmt,struct ima_field_data * field_data)45 static int ima_write_template_field_data(const void *data, const u32 datalen,
46 					 enum data_formats datafmt,
47 					 struct ima_field_data *field_data)
48 {
49 	u8 *buf, *buf_ptr;
50 	u32 buflen = datalen;
51 
52 	if (datafmt == DATA_FMT_STRING)
53 		buflen = datalen + 1;
54 
55 	buf = kzalloc(buflen, GFP_KERNEL);
56 	if (!buf)
57 		return -ENOMEM;
58 
59 	memcpy(buf, data, datalen);
60 
61 	/*
62 	 * Replace all space characters with underscore for event names and
63 	 * strings. This avoid that, during the parsing of a measurements list,
64 	 * filenames with spaces or that end with the suffix ' (deleted)' are
65 	 * split into multiple template fields (the space is the delimitator
66 	 * character for measurements lists in ASCII format).
67 	 */
68 	if (datafmt == DATA_FMT_STRING) {
69 		for (buf_ptr = buf; buf_ptr - buf < datalen; buf_ptr++)
70 			if (*buf_ptr == ' ')
71 				*buf_ptr = '_';
72 	}
73 
74 	field_data->data = buf;
75 	field_data->len = buflen;
76 	return 0;
77 }
78 
ima_show_template_data_ascii(struct seq_file * m,enum ima_show_type show,enum data_formats datafmt,struct ima_field_data * field_data)79 static void ima_show_template_data_ascii(struct seq_file *m,
80 					 enum ima_show_type show,
81 					 enum data_formats datafmt,
82 					 struct ima_field_data *field_data)
83 {
84 	u8 *buf_ptr = field_data->data;
85 	u32 buflen = field_data->len;
86 
87 	switch (datafmt) {
88 	case DATA_FMT_DIGEST_WITH_TYPE_AND_ALGO:
89 	case DATA_FMT_DIGEST_WITH_ALGO:
90 		buf_ptr = strrchr(field_data->data, ':');
91 		if (buf_ptr != field_data->data)
92 			seq_printf(m, "%s", field_data->data);
93 
94 		/* skip ':' and '\0' */
95 		buf_ptr += 2;
96 		buflen -= buf_ptr - field_data->data;
97 		fallthrough;
98 	case DATA_FMT_DIGEST:
99 	case DATA_FMT_HEX:
100 		if (!buflen)
101 			break;
102 		ima_print_digest(m, buf_ptr, buflen);
103 		break;
104 	case DATA_FMT_STRING:
105 		seq_printf(m, "%s", buf_ptr);
106 		break;
107 	case DATA_FMT_UINT:
108 		switch (field_data->len) {
109 		case sizeof(u8):
110 			seq_printf(m, "%u", *(u8 *)buf_ptr);
111 			break;
112 		case sizeof(u16):
113 			if (ima_canonical_fmt)
114 				seq_printf(m, "%u",
115 					   le16_to_cpu(*(__le16 *)buf_ptr));
116 			else
117 				seq_printf(m, "%u", *(u16 *)buf_ptr);
118 			break;
119 		case sizeof(u32):
120 			if (ima_canonical_fmt)
121 				seq_printf(m, "%u",
122 					   le32_to_cpu(*(__le32 *)buf_ptr));
123 			else
124 				seq_printf(m, "%u", *(u32 *)buf_ptr);
125 			break;
126 		case sizeof(u64):
127 			if (ima_canonical_fmt)
128 				seq_printf(m, "%llu",
129 					   le64_to_cpu(*(__le64 *)buf_ptr));
130 			else
131 				seq_printf(m, "%llu", *(u64 *)buf_ptr);
132 			break;
133 		default:
134 			break;
135 		}
136 		break;
137 	default:
138 		break;
139 	}
140 }
141 
ima_show_template_data_binary(struct seq_file * m,enum ima_show_type show,enum data_formats datafmt,struct ima_field_data * field_data)142 static void ima_show_template_data_binary(struct seq_file *m,
143 					  enum ima_show_type show,
144 					  enum data_formats datafmt,
145 					  struct ima_field_data *field_data)
146 {
147 	u32 len = (show == IMA_SHOW_BINARY_OLD_STRING_FMT) ?
148 	    strlen(field_data->data) : field_data->len;
149 
150 	if (show != IMA_SHOW_BINARY_NO_FIELD_LEN) {
151 		u32 field_len = !ima_canonical_fmt ?
152 				len : (__force u32)cpu_to_le32(len);
153 
154 		ima_putc(m, &field_len, sizeof(field_len));
155 	}
156 
157 	if (!len)
158 		return;
159 
160 	ima_putc(m, field_data->data, len);
161 }
162 
ima_show_template_field_data(struct seq_file * m,enum ima_show_type show,enum data_formats datafmt,struct ima_field_data * field_data)163 static void ima_show_template_field_data(struct seq_file *m,
164 					 enum ima_show_type show,
165 					 enum data_formats datafmt,
166 					 struct ima_field_data *field_data)
167 {
168 	switch (show) {
169 	case IMA_SHOW_ASCII:
170 		ima_show_template_data_ascii(m, show, datafmt, field_data);
171 		break;
172 	case IMA_SHOW_BINARY:
173 	case IMA_SHOW_BINARY_NO_FIELD_LEN:
174 	case IMA_SHOW_BINARY_OLD_STRING_FMT:
175 		ima_show_template_data_binary(m, show, datafmt, field_data);
176 		break;
177 	default:
178 		break;
179 	}
180 }
181 
ima_show_template_digest(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)182 void ima_show_template_digest(struct seq_file *m, enum ima_show_type show,
183 			      struct ima_field_data *field_data)
184 {
185 	ima_show_template_field_data(m, show, DATA_FMT_DIGEST, field_data);
186 }
187 
ima_show_template_digest_ng(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)188 void ima_show_template_digest_ng(struct seq_file *m, enum ima_show_type show,
189 				 struct ima_field_data *field_data)
190 {
191 	ima_show_template_field_data(m, show, DATA_FMT_DIGEST_WITH_ALGO,
192 				     field_data);
193 }
194 
ima_show_template_digest_ngv2(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)195 void ima_show_template_digest_ngv2(struct seq_file *m, enum ima_show_type show,
196 				   struct ima_field_data *field_data)
197 {
198 	ima_show_template_field_data(m, show,
199 				     DATA_FMT_DIGEST_WITH_TYPE_AND_ALGO,
200 				     field_data);
201 }
202 
ima_show_template_string(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)203 void ima_show_template_string(struct seq_file *m, enum ima_show_type show,
204 			      struct ima_field_data *field_data)
205 {
206 	ima_show_template_field_data(m, show, DATA_FMT_STRING, field_data);
207 }
208 
ima_show_template_sig(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)209 void ima_show_template_sig(struct seq_file *m, enum ima_show_type show,
210 			   struct ima_field_data *field_data)
211 {
212 	ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data);
213 }
214 
ima_show_template_buf(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)215 void ima_show_template_buf(struct seq_file *m, enum ima_show_type show,
216 			   struct ima_field_data *field_data)
217 {
218 	ima_show_template_field_data(m, show, DATA_FMT_HEX, field_data);
219 }
220 
ima_show_template_uint(struct seq_file * m,enum ima_show_type show,struct ima_field_data * field_data)221 void ima_show_template_uint(struct seq_file *m, enum ima_show_type show,
222 			    struct ima_field_data *field_data)
223 {
224 	ima_show_template_field_data(m, show, DATA_FMT_UINT, field_data);
225 }
226 
227 /**
228  * ima_parse_buf() - Parses lengths and data from an input buffer
229  * @bufstartp:       Buffer start address.
230  * @bufendp:         Buffer end address.
231  * @bufcurp:         Pointer to remaining (non-parsed) data.
232  * @maxfields:       Length of fields array.
233  * @fields:          Array containing lengths and pointers of parsed data.
234  * @curfields:       Number of array items containing parsed data.
235  * @len_mask:        Bitmap (if bit is set, data length should not be parsed).
236  * @enforce_mask:    Check if curfields == maxfields and/or bufcurp == bufendp.
237  * @bufname:         String identifier of the input buffer.
238  *
239  * Return: 0 on success, -EINVAL on error.
240  */
ima_parse_buf(void * bufstartp,void * bufendp,void ** bufcurp,int maxfields,struct ima_field_data * fields,int * curfields,unsigned long * len_mask,int enforce_mask,char * bufname)241 int ima_parse_buf(void *bufstartp, void *bufendp, void **bufcurp,
242 		  int maxfields, struct ima_field_data *fields, int *curfields,
243 		  unsigned long *len_mask, int enforce_mask, char *bufname)
244 {
245 	void *bufp = bufstartp;
246 	int i;
247 
248 	for (i = 0; i < maxfields; i++) {
249 		if (len_mask == NULL || !test_bit(i, len_mask)) {
250 			if (bufp > (bufendp - sizeof(u32)))
251 				break;
252 
253 			if (ima_canonical_fmt)
254 				fields[i].len = le32_to_cpu(*(__le32 *)bufp);
255 			else
256 				fields[i].len = *(u32 *)bufp;
257 
258 			bufp += sizeof(u32);
259 		}
260 
261 		if (bufp > (bufendp - fields[i].len))
262 			break;
263 
264 		fields[i].data = bufp;
265 		bufp += fields[i].len;
266 	}
267 
268 	if ((enforce_mask & ENFORCE_FIELDS) && i != maxfields) {
269 		pr_err("%s: nr of fields mismatch: expected: %d, current: %d\n",
270 		       bufname, maxfields, i);
271 		return -EINVAL;
272 	}
273 
274 	if ((enforce_mask & ENFORCE_BUFEND) && bufp != bufendp) {
275 		pr_err("%s: buf end mismatch: expected: %p, current: %p\n",
276 		       bufname, bufendp, bufp);
277 		return -EINVAL;
278 	}
279 
280 	if (curfields)
281 		*curfields = i;
282 
283 	if (bufcurp)
284 		*bufcurp = bufp;
285 
286 	return 0;
287 }
288 
ima_eventdigest_init_common(const u8 * digest,u32 digestsize,u8 digest_type,u8 hash_algo,struct ima_field_data * field_data)289 static int ima_eventdigest_init_common(const u8 *digest, u32 digestsize,
290 				       u8 digest_type, u8 hash_algo,
291 				       struct ima_field_data *field_data)
292 {
293 	/*
294 	 * digest formats:
295 	 *  - DATA_FMT_DIGEST: digest
296 	 *  - DATA_FMT_DIGEST_WITH_ALGO: <hash algo> + ':' + '\0' + digest,
297 	 *  - DATA_FMT_DIGEST_WITH_TYPE_AND_ALGO:
298 	 *	<digest type> + ':' + <hash algo> + ':' + '\0' + digest,
299 	 *
300 	 *    where 'DATA_FMT_DIGEST' is the original digest format ('d')
301 	 *      with a hash size limitation of 20 bytes,
302 	 *    where <digest type> is either "ima" or "verity",
303 	 *    where <hash algo> is the hash_algo_name[] string.
304 	 */
305 	u8 buffer[DIGEST_TYPE_NAME_LEN_MAX + CRYPTO_MAX_ALG_NAME + 2 +
306 		IMA_MAX_DIGEST_SIZE] = { 0 };
307 	enum data_formats fmt = DATA_FMT_DIGEST;
308 	u32 offset = 0;
309 
310 	if (digest_type < DIGEST_TYPE__LAST && hash_algo < HASH_ALGO__LAST) {
311 		fmt = DATA_FMT_DIGEST_WITH_TYPE_AND_ALGO;
312 		offset += 1 + sprintf(buffer, "%s:%s:",
313 				      digest_type_name[digest_type],
314 				      hash_algo_name[hash_algo]);
315 	} else if (hash_algo < HASH_ALGO__LAST) {
316 		fmt = DATA_FMT_DIGEST_WITH_ALGO;
317 		offset += 1 + sprintf(buffer, "%s:",
318 				      hash_algo_name[hash_algo]);
319 	}
320 
321 	if (digest)
322 		memcpy(buffer + offset, digest, digestsize);
323 	else
324 		/*
325 		 * If digest is NULL, the event being recorded is a violation.
326 		 * Make room for the digest by increasing the offset by the
327 		 * hash algorithm digest size.
328 		 */
329 		offset += hash_digest_size[hash_algo];
330 
331 	return ima_write_template_field_data(buffer, offset + digestsize,
332 					     fmt, field_data);
333 }
334 
335 /*
336  * This function writes the digest of an event (with size limit).
337  */
ima_eventdigest_init(struct ima_event_data * event_data,struct ima_field_data * field_data)338 int ima_eventdigest_init(struct ima_event_data *event_data,
339 			 struct ima_field_data *field_data)
340 {
341 	struct ima_max_digest_data hash;
342 	u8 *cur_digest = NULL;
343 	u32 cur_digestsize = 0;
344 	struct inode *inode;
345 	int result;
346 
347 	memset(&hash, 0, sizeof(hash));
348 
349 	if (event_data->violation)	/* recording a violation. */
350 		goto out;
351 
352 	if (ima_template_hash_algo_allowed(event_data->iint->ima_hash->algo)) {
353 		cur_digest = event_data->iint->ima_hash->digest;
354 		cur_digestsize = event_data->iint->ima_hash->length;
355 		goto out;
356 	}
357 
358 	if ((const char *)event_data->filename == boot_aggregate_name) {
359 		if (ima_tpm_chip) {
360 			hash.hdr.algo = HASH_ALGO_SHA1;
361 			result = ima_calc_boot_aggregate(&hash.hdr);
362 
363 			/* algo can change depending on available PCR banks */
364 			if (!result && hash.hdr.algo != HASH_ALGO_SHA1)
365 				result = -EINVAL;
366 
367 			if (result < 0)
368 				memset(&hash, 0, sizeof(hash));
369 		}
370 
371 		cur_digest = hash.hdr.digest;
372 		cur_digestsize = hash_digest_size[HASH_ALGO_SHA1];
373 		goto out;
374 	}
375 
376 	if (!event_data->file)	/* missing info to re-calculate the digest */
377 		return -EINVAL;
378 
379 	inode = file_inode(event_data->file);
380 	hash.hdr.algo = ima_template_hash_algo_allowed(ima_hash_algo) ?
381 	    ima_hash_algo : HASH_ALGO_SHA1;
382 	result = ima_calc_file_hash(event_data->file, &hash.hdr);
383 	if (result) {
384 		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode,
385 				    event_data->filename, "collect_data",
386 				    "failed", result, 0);
387 		return result;
388 	}
389 	cur_digest = hash.hdr.digest;
390 	cur_digestsize = hash.hdr.length;
391 out:
392 	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
393 					   DIGEST_TYPE__LAST, HASH_ALGO__LAST,
394 					   field_data);
395 }
396 
397 /*
398  * This function writes the digest of an event (without size limit).
399  */
ima_eventdigest_ng_init(struct ima_event_data * event_data,struct ima_field_data * field_data)400 int ima_eventdigest_ng_init(struct ima_event_data *event_data,
401 			    struct ima_field_data *field_data)
402 {
403 	u8 *cur_digest = NULL, hash_algo = ima_hash_algo;
404 	u32 cur_digestsize = 0;
405 
406 	if (event_data->violation)	/* recording a violation. */
407 		goto out;
408 
409 	cur_digest = event_data->iint->ima_hash->digest;
410 	cur_digestsize = event_data->iint->ima_hash->length;
411 
412 	hash_algo = event_data->iint->ima_hash->algo;
413 out:
414 	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
415 					   DIGEST_TYPE__LAST, hash_algo,
416 					   field_data);
417 }
418 
419 /*
420  * This function writes the digest of an event (without size limit),
421  * prefixed with both the digest type and hash algorithm.
422  */
ima_eventdigest_ngv2_init(struct ima_event_data * event_data,struct ima_field_data * field_data)423 int ima_eventdigest_ngv2_init(struct ima_event_data *event_data,
424 			      struct ima_field_data *field_data)
425 {
426 	u8 *cur_digest = NULL, hash_algo = ima_hash_algo;
427 	u32 cur_digestsize = 0;
428 	u8 digest_type = DIGEST_TYPE_IMA;
429 
430 	if (event_data->violation)	/* recording a violation. */
431 		goto out;
432 
433 	cur_digest = event_data->iint->ima_hash->digest;
434 	cur_digestsize = event_data->iint->ima_hash->length;
435 
436 	hash_algo = event_data->iint->ima_hash->algo;
437 	if (event_data->iint->flags & IMA_VERITY_REQUIRED)
438 		digest_type = DIGEST_TYPE_VERITY;
439 out:
440 	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
441 					   digest_type, hash_algo,
442 					   field_data);
443 }
444 
445 /*
446  * This function writes the digest of the file which is expected to match the
447  * digest contained in the file's appended signature.
448  */
ima_eventdigest_modsig_init(struct ima_event_data * event_data,struct ima_field_data * field_data)449 int ima_eventdigest_modsig_init(struct ima_event_data *event_data,
450 				struct ima_field_data *field_data)
451 {
452 	enum hash_algo hash_algo;
453 	const u8 *cur_digest;
454 	u32 cur_digestsize;
455 
456 	if (!event_data->modsig)
457 		return 0;
458 
459 	if (event_data->violation) {
460 		/* Recording a violation. */
461 		hash_algo = HASH_ALGO_SHA1;
462 		cur_digest = NULL;
463 		cur_digestsize = 0;
464 	} else {
465 		int rc;
466 
467 		rc = ima_get_modsig_digest(event_data->modsig, &hash_algo,
468 					   &cur_digest, &cur_digestsize);
469 		if (rc)
470 			return rc;
471 		else if (hash_algo == HASH_ALGO__LAST || cur_digestsize == 0)
472 			/* There was some error collecting the digest. */
473 			return -EINVAL;
474 	}
475 
476 	return ima_eventdigest_init_common(cur_digest, cur_digestsize,
477 					   DIGEST_TYPE__LAST, hash_algo,
478 					   field_data);
479 }
480 
ima_eventname_init_common(struct ima_event_data * event_data,struct ima_field_data * field_data,bool size_limit)481 static int ima_eventname_init_common(struct ima_event_data *event_data,
482 				     struct ima_field_data *field_data,
483 				     bool size_limit)
484 {
485 	const char *cur_filename = NULL;
486 	u32 cur_filename_len = 0;
487 
488 	BUG_ON(event_data->filename == NULL && event_data->file == NULL);
489 
490 	if (event_data->filename) {
491 		cur_filename = event_data->filename;
492 		cur_filename_len = strlen(event_data->filename);
493 
494 		if (!size_limit || cur_filename_len <= IMA_EVENT_NAME_LEN_MAX)
495 			goto out;
496 	}
497 
498 	if (event_data->file) {
499 		cur_filename = event_data->file->f_path.dentry->d_name.name;
500 		cur_filename_len = strlen(cur_filename);
501 	} else
502 		/*
503 		 * Truncate filename if the latter is too long and
504 		 * the file descriptor is not available.
505 		 */
506 		cur_filename_len = IMA_EVENT_NAME_LEN_MAX;
507 out:
508 	return ima_write_template_field_data(cur_filename, cur_filename_len,
509 					     DATA_FMT_STRING, field_data);
510 }
511 
512 /*
513  * This function writes the name of an event (with size limit).
514  */
ima_eventname_init(struct ima_event_data * event_data,struct ima_field_data * field_data)515 int ima_eventname_init(struct ima_event_data *event_data,
516 		       struct ima_field_data *field_data)
517 {
518 	return ima_eventname_init_common(event_data, field_data, true);
519 }
520 
521 /*
522  * This function writes the name of an event (without size limit).
523  */
ima_eventname_ng_init(struct ima_event_data * event_data,struct ima_field_data * field_data)524 int ima_eventname_ng_init(struct ima_event_data *event_data,
525 			  struct ima_field_data *field_data)
526 {
527 	return ima_eventname_init_common(event_data, field_data, false);
528 }
529 
530 /*
531  *  ima_eventsig_init - include the file signature as part of the template data
532  */
ima_eventsig_init(struct ima_event_data * event_data,struct ima_field_data * field_data)533 int ima_eventsig_init(struct ima_event_data *event_data,
534 		      struct ima_field_data *field_data)
535 {
536 	struct evm_ima_xattr_data *xattr_value = event_data->xattr_value;
537 
538 	if (!xattr_value ||
539 	    (xattr_value->type != EVM_IMA_XATTR_DIGSIG &&
540 	     xattr_value->type != IMA_VERITY_DIGSIG))
541 		return ima_eventevmsig_init(event_data, field_data);
542 
543 	return ima_write_template_field_data(xattr_value, event_data->xattr_len,
544 					     DATA_FMT_HEX, field_data);
545 }
546 
547 /*
548  *  ima_eventbuf_init - include the buffer(kexec-cmldine) as part of the
549  *  template data.
550  */
ima_eventbuf_init(struct ima_event_data * event_data,struct ima_field_data * field_data)551 int ima_eventbuf_init(struct ima_event_data *event_data,
552 		      struct ima_field_data *field_data)
553 {
554 	if ((!event_data->buf) || (event_data->buf_len == 0))
555 		return 0;
556 
557 	return ima_write_template_field_data(event_data->buf,
558 					     event_data->buf_len, DATA_FMT_HEX,
559 					     field_data);
560 }
561 
562 /*
563  *  ima_eventmodsig_init - include the appended file signature as part of the
564  *  template data
565  */
ima_eventmodsig_init(struct ima_event_data * event_data,struct ima_field_data * field_data)566 int ima_eventmodsig_init(struct ima_event_data *event_data,
567 			 struct ima_field_data *field_data)
568 {
569 	const void *data;
570 	u32 data_len;
571 	int rc;
572 
573 	if (!event_data->modsig)
574 		return 0;
575 
576 	/*
577 	 * modsig is a runtime structure containing pointers. Get its raw data
578 	 * instead.
579 	 */
580 	rc = ima_get_raw_modsig(event_data->modsig, &data, &data_len);
581 	if (rc)
582 		return rc;
583 
584 	return ima_write_template_field_data(data, data_len, DATA_FMT_HEX,
585 					     field_data);
586 }
587 
588 /*
589  *  ima_eventevmsig_init - include the EVM portable signature as part of the
590  *  template data
591  */
ima_eventevmsig_init(struct ima_event_data * event_data,struct ima_field_data * field_data)592 int ima_eventevmsig_init(struct ima_event_data *event_data,
593 			 struct ima_field_data *field_data)
594 {
595 	struct evm_ima_xattr_data *xattr_data = NULL;
596 	int rc = 0;
597 
598 	if (!event_data->file)
599 		return 0;
600 
601 	rc = vfs_getxattr_alloc(&init_user_ns, file_dentry(event_data->file),
602 				XATTR_NAME_EVM, (char **)&xattr_data, 0,
603 				GFP_NOFS);
604 	if (rc <= 0)
605 		return 0;
606 
607 	if (xattr_data->type != EVM_XATTR_PORTABLE_DIGSIG) {
608 		kfree(xattr_data);
609 		return 0;
610 	}
611 
612 	rc = ima_write_template_field_data((char *)xattr_data, rc, DATA_FMT_HEX,
613 					   field_data);
614 	kfree(xattr_data);
615 	return rc;
616 }
617 
ima_eventinodedac_init_common(struct ima_event_data * event_data,struct ima_field_data * field_data,bool get_uid)618 static int ima_eventinodedac_init_common(struct ima_event_data *event_data,
619 					 struct ima_field_data *field_data,
620 					 bool get_uid)
621 {
622 	unsigned int id;
623 
624 	if (!event_data->file)
625 		return 0;
626 
627 	if (get_uid)
628 		id = i_uid_read(file_inode(event_data->file));
629 	else
630 		id = i_gid_read(file_inode(event_data->file));
631 
632 	if (ima_canonical_fmt) {
633 		if (sizeof(id) == sizeof(u16))
634 			id = (__force u16)cpu_to_le16(id);
635 		else
636 			id = (__force u32)cpu_to_le32(id);
637 	}
638 
639 	return ima_write_template_field_data((void *)&id, sizeof(id),
640 					     DATA_FMT_UINT, field_data);
641 }
642 
643 /*
644  *  ima_eventinodeuid_init - include the inode UID as part of the template
645  *  data
646  */
ima_eventinodeuid_init(struct ima_event_data * event_data,struct ima_field_data * field_data)647 int ima_eventinodeuid_init(struct ima_event_data *event_data,
648 			   struct ima_field_data *field_data)
649 {
650 	return ima_eventinodedac_init_common(event_data, field_data, true);
651 }
652 
653 /*
654  *  ima_eventinodegid_init - include the inode GID as part of the template
655  *  data
656  */
ima_eventinodegid_init(struct ima_event_data * event_data,struct ima_field_data * field_data)657 int ima_eventinodegid_init(struct ima_event_data *event_data,
658 			   struct ima_field_data *field_data)
659 {
660 	return ima_eventinodedac_init_common(event_data, field_data, false);
661 }
662 
663 /*
664  *  ima_eventinodemode_init - include the inode mode as part of the template
665  *  data
666  */
ima_eventinodemode_init(struct ima_event_data * event_data,struct ima_field_data * field_data)667 int ima_eventinodemode_init(struct ima_event_data *event_data,
668 			    struct ima_field_data *field_data)
669 {
670 	struct inode *inode;
671 	u16 mode;
672 
673 	if (!event_data->file)
674 		return 0;
675 
676 	inode = file_inode(event_data->file);
677 	mode = inode->i_mode;
678 	if (ima_canonical_fmt)
679 		mode = (__force u16)cpu_to_le16(mode);
680 
681 	return ima_write_template_field_data((char *)&mode, sizeof(mode),
682 					     DATA_FMT_UINT, field_data);
683 }
684 
ima_eventinodexattrs_init_common(struct ima_event_data * event_data,struct ima_field_data * field_data,char type)685 static int ima_eventinodexattrs_init_common(struct ima_event_data *event_data,
686 					    struct ima_field_data *field_data,
687 					    char type)
688 {
689 	u8 *buffer = NULL;
690 	int rc;
691 
692 	if (!event_data->file)
693 		return 0;
694 
695 	rc = evm_read_protected_xattrs(file_dentry(event_data->file), NULL, 0,
696 				       type, ima_canonical_fmt);
697 	if (rc < 0)
698 		return 0;
699 
700 	buffer = kmalloc(rc, GFP_KERNEL);
701 	if (!buffer)
702 		return 0;
703 
704 	rc = evm_read_protected_xattrs(file_dentry(event_data->file), buffer,
705 				       rc, type, ima_canonical_fmt);
706 	if (rc < 0) {
707 		rc = 0;
708 		goto out;
709 	}
710 
711 	rc = ima_write_template_field_data((char *)buffer, rc, DATA_FMT_HEX,
712 					   field_data);
713 out:
714 	kfree(buffer);
715 	return rc;
716 }
717 
718 /*
719  *  ima_eventinodexattrnames_init - include a list of xattr names as part of the
720  *  template data
721  */
ima_eventinodexattrnames_init(struct ima_event_data * event_data,struct ima_field_data * field_data)722 int ima_eventinodexattrnames_init(struct ima_event_data *event_data,
723 				  struct ima_field_data *field_data)
724 {
725 	return ima_eventinodexattrs_init_common(event_data, field_data, 'n');
726 }
727 
728 /*
729  *  ima_eventinodexattrlengths_init - include a list of xattr lengths as part of
730  *  the template data
731  */
ima_eventinodexattrlengths_init(struct ima_event_data * event_data,struct ima_field_data * field_data)732 int ima_eventinodexattrlengths_init(struct ima_event_data *event_data,
733 				    struct ima_field_data *field_data)
734 {
735 	return ima_eventinodexattrs_init_common(event_data, field_data, 'l');
736 }
737 
738 /*
739  *  ima_eventinodexattrvalues_init - include a list of xattr values as part of
740  *  the template data
741  */
ima_eventinodexattrvalues_init(struct ima_event_data * event_data,struct ima_field_data * field_data)742 int ima_eventinodexattrvalues_init(struct ima_event_data *event_data,
743 				   struct ima_field_data *field_data)
744 {
745 	return ima_eventinodexattrs_init_common(event_data, field_data, 'v');
746 }
747