1 // SPDX-License-Identifier: GPL-2.0-only
54 	if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {  in hash_setup()
94 	    mapping_writably_mapped(file->f_mapping)) {  in mmap_violation_check()
95 		rc = -ETXTBSY;  in mmap_violation_check()
98 		if (!*pathbuf)	/* ima_rdwr_violation possibly pre-fetched */  in mmap_violation_check()
99 			*pathname = ima_d_path(&file->f_path, pathbuf,  in mmap_violation_check()
111  *	- Opening a file for write when already open for read,
113  *	- Opening a file for read when already open for write,
125 	fmode_t mode = file->f_mode;  in ima_rdwr_violation_check()
129 		if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {  in ima_rdwr_violation_check()
135 						       &iint->atomic_flags))  in ima_rdwr_violation_check()
140 			set_bit(IMA_MAY_EMIT_TOMTOU, &iint->atomic_flags);  in ima_rdwr_violation_check()
145 					      &iint->atomic_flags))  in ima_rdwr_violation_check()
153 	*pathname = ima_d_path(&file->f_path, pathbuf, filename);  in ima_rdwr_violation_check()
166 	fmode_t mode = file->f_mode;  in ima_check_last_writer()
172 	mutex_lock(&iint->mutex);  in ima_check_last_writer()
173 	if (atomic_read(&inode->i_writecount) == 1) {  in ima_check_last_writer()
176 		clear_bit(IMA_EMITTED_OPENWRITERS, &iint->atomic_flags);  in ima_check_last_writer()
179 					    &iint->atomic_flags);  in ima_check_last_writer()
180 		if ((iint->flags & IMA_NEW_FILE) ||  in ima_check_last_writer()
181 		    vfs_getattr_nosec(&file->f_path, &stat,  in ima_check_last_writer()
185 		    stat.change_cookie != iint->real_inode.version) {  in ima_check_last_writer()
186 			iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);  in ima_check_last_writer()
187 			iint->measured_pcrs = 0;  in ima_check_last_writer()
192 	mutex_unlock(&iint->mutex);  in ima_check_last_writer()
196  * ima_file_free - called on __fput()
206 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))  in ima_file_free()
236 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))  in process_measurement()
240 	 * bitmask based on the appraise/audit/measurement policy.  in process_measurement()
263 			rc = -ENOMEM;  in process_measurement()
277 	mutex_lock(&iint->mutex);  in process_measurement()
279 	if (test_and_clear_bit(IMA_CHANGE_ATTR, &iint->atomic_flags))  in process_measurement()
281 		 * Reset appraisal flags (action and non-action rule-specific)  in process_measurement()
284 		iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |  in process_measurement()
289 	 * Re-evaulate the file if either the xattr has changed or the  in process_measurement()
290 	 * kernel has no way of detecting file change on the filesystem.  in process_measurement()
293 	if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags) ||  in process_measurement()
294 	    ((inode->i_sb->s_iflags & SB_I_IMA_UNVERIFIABLE_SIGNATURE) &&  in process_measurement()
295 	     !(inode->i_sb->s_iflags & SB_I_UNTRUSTED_MOUNTER) &&  in process_measurement()
297 		iint->flags &= ~IMA_DONE_MASK;  in process_measurement()
298 		iint->measured_pcrs = 0;  in process_measurement()
302 	 * On stacked filesystems, detect and re-evaluate file data and  in process_measurement()
307 	    (action & IMA_DO_MASK) && (iint->flags & IMA_DONE_MASK)) {  in process_measurement()
309 		    integrity_inode_attrs_changed(&iint->real_inode,  in process_measurement()
311 			iint->flags &= ~IMA_DONE_MASK;  in process_measurement()
312 			iint->measured_pcrs = 0;  in process_measurement()
321 			iint->flags &= ~(IMA_APPRAISED |  in process_measurement()
329 	iint->flags |= action;  in process_measurement()
331 	action &= ~((iint->flags & (IMA_DONE_MASK ^ IMA_MEASURED)) >> 1);  in process_measurement()
334 	if ((action & IMA_MEASURE) && (iint->measured_pcrs & (0x1 << pcr)))  in process_measurement()
339 	    !(test_bit(IMA_DIGSIG, &iint->atomic_flags))) {  in process_measurement()
343 		    (xattr_value->type == EVM_IMA_XATTR_DIGSIG))  in process_measurement()
344 			set_bit(IMA_DIGSIG, &iint->atomic_flags);  in process_measurement()
345 		iint->flags |= IMA_HASHED;  in process_measurement()
347 		set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);  in process_measurement()
362 	    strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0) {  in process_measurement()
368 		 * Read the appended modsig if allowed by the policy, and allow  in process_measurement()
372 		if (iint->flags & IMA_MODSIG_ALLOWED) {  in process_measurement()
376 			    iint->flags & IMA_MEASURED)  in process_measurement()
384 	if (rc != 0 && rc != -EBADF && rc != -EINVAL)  in process_measurement()
387 	if (!pathbuf)	/* ima_rdwr_violation possibly pre-fetched */  in process_measurement()
388 		pathname = ima_d_path(&file->f_path, &pathbuf, filename);  in process_measurement()
396 		if (rc != -EPERM) {  in process_measurement()
410 	if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))  in process_measurement()
416 		rc = -EACCES;  in process_measurement()
420 				    "denied-hash-algorithm", rc, 0);  in process_measurement()
423 	if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) &&  in process_measurement()
424 	     !(iint->flags & IMA_NEW_FILE))  in process_measurement()
425 		rc = -EACCES;  in process_measurement()
426 	mutex_unlock(&iint->mutex);  in process_measurement()
434 			return -EACCES;  in process_measurement()
435 		if (file->f_mode & FMODE_WRITE)  in process_measurement()
436 			set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);  in process_measurement()
442  * ima_file_mmap - based on policy, collect/store measurement.
445  * @prot: protection that will be applied by the kernel
449  * policy decision.
452  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
480  * ima_file_mprotect - based on policy, limit mprotect change
483  * @prot: protection that will be applied by the kernel
486  * IMA's mmap appraisal policy rules.  Due to locking issues (mmap semaphore
489  * PROT_EXECUTE change, if an mmap appraise policy rule exists.
491  * On mprotect change success, return 0.  On failure, return -EACESS.
508 	if (!(ima_policy_flag & IMA_APPRAISE) || !vma->vm_file ||  in ima_file_mprotect()
509 	    !(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))  in ima_file_mprotect()
513 	inode = file_inode(vma->vm_file);  in ima_file_mprotect()
514 	action = ima_get_action(file_mnt_idmap(vma->vm_file), inode,  in ima_file_mprotect()
517 	action |= ima_get_action(file_mnt_idmap(vma->vm_file), inode,  in ima_file_mprotect()
522 	/* Is the mmap'ed file in policy? */  in ima_file_mprotect()
527 		result = -EPERM;  in ima_file_mprotect()
529 	file = vma->vm_file;  in ima_file_mprotect()
530 	pathname = ima_d_path(&file->f_path, &pathbuf, filename);  in ima_file_mprotect()
532 			    "collect_data", "failed-mprotect", result, 0);  in ima_file_mprotect()
540  * ima_bprm_check - based on policy, collect/store measurement.
550  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
558 	ret = process_measurement(bprm->file, current_cred(),  in ima_bprm_check()
563 	security_cred_getlsmprop(bprm->cred, &prop);  in ima_bprm_check()
564 	return process_measurement(bprm->file, bprm->cred, &prop, NULL, 0,  in ima_bprm_check()
569  * ima_bprm_creds_for_exec - collect/store/appraise measurement.
572  * Based on the IMA policy and the execveat(2) AT_EXECVE_CHECK flag, measure
574  * Unlike any of the other LSM hooks where the kernel enforces file integrity,
579  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
590 	if (!bprm->is_check)  in ima_bprm_creds_for_exec()
597  * ima_file_check - based on policy, collect/store measurement.
601  * Measure files based on the ima_must_measure() policy decision.
604  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
625 			mutex_lock(&iint->mutex);  in __ima_inode_hash()
628 	if ((!iint || !(iint->flags & IMA_COLLECTED)) && file) {  in __ima_inode_hash()
630 			mutex_unlock(&iint->mutex);  in __ima_inode_hash()
639 			if (rc != -ENOMEM)  in __ima_inode_hash()
642 			return -EOPNOTSUPP;  in __ima_inode_hash()
646 		mutex_lock(&iint->mutex);  in __ima_inode_hash()
650 		return -EOPNOTSUPP;  in __ima_inode_hash()
656 	if (!iint->ima_hash || !(iint->flags & IMA_COLLECTED)) {  in __ima_inode_hash()
657 		mutex_unlock(&iint->mutex);  in __ima_inode_hash()
658 		return -EOPNOTSUPP;  in __ima_inode_hash()
664 		copied_size = min_t(size_t, iint->ima_hash->length, buf_size);  in __ima_inode_hash()
665 		memcpy(buf, iint->ima_hash->digest, copied_size);  in __ima_inode_hash()
667 	hash_algo = iint->ima_hash->algo;  in __ima_inode_hash()
668 	mutex_unlock(&iint->mutex);  in __ima_inode_hash()
671 		kfree(iint->ima_hash);  in __ima_inode_hash()
677  * ima_file_hash - return a measurement of the file
690  * If the measurement cannot be performed, return -EOPNOTSUPP.
691  * If the parameters are incorrect, return -EINVAL.
696 		return -EINVAL;  in ima_file_hash()
703  * ima_inode_hash - return the stored measurement if the inode has been hashed
717  * If IMA is disabled or if no measurement is available, return -EOPNOTSUPP.
718  * If the parameters are incorrect, return -EINVAL.
723 		return -EINVAL;  in ima_inode_hash()
730  * ima_post_create_tmpfile - mark newly created tmpfile as new
736  * tmpfiles are in policy.
745 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))  in ima_post_create_tmpfile()
759 	set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);  in ima_post_create_tmpfile()
760 	iint->ima_file_status = INTEGRITY_PASS;  in ima_post_create_tmpfile()
764  * ima_post_path_mknod - mark as a new inode
774 	struct inode *inode = dentry->d_inode;  in ima_post_path_mknod()
777 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))  in ima_post_path_mknod()
790 	/* needed for re-opening empty files */  in ima_post_path_mknod()
791 	iint->flags |= IMA_NEW_FILE;  in ima_post_path_mknod()
795  * ima_read_file - pre-measure/appraise hook decision based on policy
800  * Permit reading a file based on policy. The policy rules are written
801  * in terms of the policy identifier.  Appraising the integrity of
804  * For permission return 0, otherwise return -EACCES.
813 	 * Do devices using pre-allocated memory run the risk of the  in ima_read_file()
844  * ima_post_read_file - in memory collect/appraise/audit measurement
850  * Measure/appraise/audit in memory file based on policy.  Policy rules
851  * are written in terms of a policy identifier.
854  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
868 			return -EACCES;  in ima_post_read_file()
879  * ima_load_data - appraise decision based on policy
880  * @id: kernel load data caller identifier
885  * data provided by userspace.  Enforce policy rules requiring a file
886  * signature (eg. kexec'ed kernel image).
888  * For permission return 0, otherwise return -EACCES.
901 …pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load…  in ima_load_data()
902 			return -EACCES;  in ima_load_data()
906 …pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load…  in ima_load_data()
907 			return -EACCES;	/* INTEGRITY_UNKNOWN */  in ima_load_data()
913 			return -EACCES;	/* INTEGRITY_UNKNOWN */  in ima_load_data()
921 …pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter mi…  in ima_load_data()
922 			return -EACCES;	/* INTEGRITY_UNKNOWN */  in ima_load_data()
932  * ima_post_load_data - appraise decision based on policy
935  * @load_id: kernel load data caller identifier
936  * @description: @load_id-specific description of contents
938  * Measure/appraise/audit in memory buffer based on policy.  Policy rules
939  * are written in terms of a policy identifier.
942  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
952 			return -EACCES; /* INTEGRITY_UNKNOWN */  in ima_post_load_data()
968  * process_buffer_measurement - Measure the buffer or the buffer data hash
981  * Based on policy, either the buffer data or buffer data hash is measured
1012 		return -EINVAL;  in process_buffer_measurement()
1015 		return -ENOENT;  in process_buffer_measurement()
1019 		ret = -EINVAL;  in process_buffer_measurement()
1026 	 * based on policy. To avoid code duplication, differentiate  in process_buffer_measurement()
1028 	 * retrieving the policy rule information only for the LSM hook  in process_buffer_measurement()
1037 			return -ENOENT;  in process_buffer_measurement()
1044 	iint.ima_hash->algo = ima_hash_algo;  in process_buffer_measurement()
1045 	iint.ima_hash->length = hash_digest_size[ima_hash_algo];  in process_buffer_measurement()
1054 		memcpy(digest_hash, hash_hdr->digest, digest_hash_len);  in process_buffer_measurement()
1068 		memcpy(digest, iint.ima_hash->digest, digest_hash_len);  in process_buffer_measurement()
1095  * ima_kexec_cmdline - measure kexec cmdline boot args
1096  * @kernel_fd: file descriptor of the kexec kernel being loaded
1112 				   buf, size, "kexec-cmdline", KEXEC_CMDLINE, 0,  in ima_kexec_cmdline()
1117  * ima_measure_critical_data - measure kernel integrity critical data
1126  * Measure data critical to the integrity of the kernel into the IMA log
1128  * structures, policies, and states stored in kernel memory that can
1141 		return -ENOPARAM;  in ima_measure_critical_data()
1153  * ima_kernel_module_request - Prevent crypto-pkcs1(rsa,*) requests
1154  * @kmod_name: kernel module name
1157  * binary requires executing modprobe itself. Since the modprobe iint->mutex
1165  * in order to load a kernel module with same name.
1167  * Since we don't have any real "crypto-pkcs1(rsa,*)" kernel modules,
1171  * Return: Zero if it is safe to load the kernel module, -EINVAL otherwise.
1175 	if (strncmp(kmod_name, "crypto-pkcs1(rsa,", 17) == 0)  in ima_kernel_module_request()
1176 		return -EINVAL;  in ima_kernel_module_request()