13  * File: ima_main.c
19 #include <linux/file.h>
84 /* Prevent mmap'ing a file execute that is already mmap'ed write */
85 static int mmap_violation_check(enum ima_hooks func, struct file *file,  in mmap_violation_check()  argument
93 	    mapping_writably_mapped(file->f_mapping)) {  in mmap_violation_check()
95 		inode = file_inode(file);  in mmap_violation_check()
98 			*pathname = ima_d_path(&file->f_path, pathbuf,  in mmap_violation_check()
110  *	- Opening a file for write when already open for read,
112  *	- Opening a file for read when already open for write,
113  *	  could result in a file measurement error.
116 static void ima_rdwr_violation_check(struct file *file,  in ima_rdwr_violation_check()  argument
123 	struct inode *inode = file_inode(file);  in ima_rdwr_violation_check()
124 	fmode_t mode = file->f_mode;  in ima_rdwr_violation_check()
146 	*pathname = ima_d_path(&file->f_path, pathbuf, filename);  in ima_rdwr_violation_check()
149 		ima_add_violation(file, *pathname, iint,  in ima_rdwr_violation_check()
152 		ima_add_violation(file, *pathname, iint,  in ima_rdwr_violation_check()
157 				  struct inode *inode, struct file *file)  in ima_check_last_writer()  argument
159 	fmode_t mode = file->f_mode;  in ima_check_last_writer()
172 		    vfs_getattr_nosec(&file->f_path, &stat,  in ima_check_last_writer()
180 				ima_update_xattr(iint, file);  in ima_check_last_writer()
188  * @file: pointer to file structure being freed
192 void ima_file_free(struct file *file)  in ima_file_free()  argument
194 	struct inode *inode = file_inode(file);  in ima_file_free()
204 	ima_check_last_writer(iint, inode, file);  in ima_file_free()
207 static int process_measurement(struct file *file, const struct cred *cred,  in process_measurement()  argument
211 	struct inode *backing_inode, *inode = file_inode(file);  in process_measurement()
233 	action = ima_get_action(file_mnt_idmap(file), inode, cred, secid,  in process_measurement()
257 		ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,  in process_measurement()
276 	 * Re-evaulate the file if either the xattr has changed or the  in process_measurement()
277 	 * kernel has no way of detecting file change on the filesystem.  in process_measurement()
288 	/* Detect and re-evaluate changes made to the backing file. */  in process_measurement()
289 	backing_inode = d_real_inode(file_dentry(file));  in process_measurement()
316 		xattr_len = ima_read_xattr(file_dentry(file),  in process_measurement()
329 			rc = mmap_violation_check(func, file, &pathbuf,  in process_measurement()
340 		xattr_len = ima_read_xattr(file_dentry(file),  in process_measurement()
346 		 * template format and whether the file was already measured.  in process_measurement()
359 	rc = ima_collect_measurement(iint, file, buf, size, hash_algo, modsig);  in process_measurement()
364 		pathname = ima_d_path(&file->f_path, &pathbuf, filename);  in process_measurement()
367 		ima_store_measurement(iint, file, pathname,  in process_measurement()
374 			rc = ima_appraise_measurement(func, iint, file,  in process_measurement()
380 			rc = mmap_violation_check(func, file, &pathbuf,  in process_measurement()
386 	if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))  in process_measurement()
394 		integrity_audit_msg(AUDIT_INTEGRITY_DATA, file_inode(file),  in process_measurement()
411 		if (file->f_mode & FMODE_WRITE)  in process_measurement()
419  * @file: pointer to the file to be measured (May be NULL)
427  * On success return 0.  On integrity appraisal error, assuming the file
430 int ima_file_mmap(struct file *file, unsigned long reqprot,  in ima_file_mmap()  argument
436 	if (!file)  in ima_file_mmap()
442 		ret = process_measurement(file, current_cred(), secid, NULL,  in ima_file_mmap()
449 		return process_measurement(file, current_cred(), secid, NULL,  in ima_file_mmap()
471 	struct file *file;  in ima_file_mprotect()  local
481 	/* Is mprotect making an mmap'ed file executable? */  in ima_file_mprotect()
496 	/* Is the mmap'ed file in policy? */  in ima_file_mprotect()
503 	file = vma->vm_file;  in ima_file_mprotect()
504 	pathname = ima_d_path(&file->f_path, &pathbuf, filename);  in ima_file_mprotect()
517  * The OS protects against an executable file, already open for write,
518  * from being executed in deny_write_access() and an executable file,
523  * On success return 0.  On integrity appraisal error, assuming the file
532 	ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0,  in ima_bprm_check()
538 	return process_measurement(bprm->file, bprm->cred, secid, NULL, 0,  in ima_bprm_check()
544  * @file: pointer to the file to be measured
549  * On success return 0.  On integrity appraisal error, assuming the file
552 int ima_file_check(struct file *file, int mask)  in ima_file_check()  argument
557 	return process_measurement(file, current_cred(), secid, NULL, 0,  in ima_file_check()
563 static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf,  in __ima_inode_hash()  argument
575 	if ((!iint || !(iint->flags & IMA_COLLECTED)) && file) {  in __ima_inode_hash()
583 		rc = ima_collect_measurement(&tmp_iint, file, NULL, 0,  in __ima_inode_hash()
625  * ima_file_hash - return a measurement of the file
626  * @file: pointer to the file
635  * The file hash returned is based on the entire file, including the appended
641 int ima_file_hash(struct file *file, char *buf, size_t buf_size)  in ima_file_hash()  argument
643 	if (!file)  in ima_file_hash()
646 	return __ima_inode_hash(file_inode(file), file, buf, buf_size);  in ima_file_hash()
716  * file data can be written later.
744  * @file: pointer to the file to be measured/appraised/audit
748  * Permit reading a file based on policy. The policy rules are written
750  * a file requires a file descriptor.
754 int ima_read_file(struct file *file, enum kernel_read_file_id read_id,  in ima_read_file()  argument
776 	/* Read entire file for all partial reads. */  in ima_read_file()
779 	return process_measurement(file, current_cred(), secid, NULL,  in ima_read_file()
793  * @file: pointer to the file to be measured/appraised/audit
794  * @buf: pointer to in memory file contents
795  * @size: size of in memory file contents
798  * Measure/appraise/audit in memory file based on policy.  Policy rules
801  * On success return 0.  On integrity appraisal error, assuming the file
804 int ima_post_read_file(struct file *file, void *buf, loff_t size,  in ima_post_read_file()  argument
811 	if (!file && read_id == READING_X509_CERTIFICATE)  in ima_post_read_file()
814 	if (!file || !buf || size == 0) { /* should never happen */  in ima_post_read_file()
822 	return process_measurement(file, current_cred(), secid, buf, size,  in ima_post_read_file()
833  * data provided by userspace.  Enforce policy rules requiring a file
849 …pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load…  in ima_load_data()
854 …pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load…  in ima_load_data()
869 …pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter mi…  in ima_load_data()
881  * @buf: pointer to in memory file contents
882  * @size: size of in memory file contents
889  * On success return 0.  On integrity appraisal error, assuming the file
1035  * @kernel_fd: file descriptor of the kexec kernel being loaded
1049 	if (!f.file)  in ima_kexec_cmdline()
1052 	process_buffer_measurement(file_mnt_idmap(f.file), file_inode(f.file),  in ima_kexec_cmdline()