1 files changed, 120 insertions, 102 deletions

diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index dba965de90d..09baa335ebc 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/xattr.h>
 #include <linux/ima.h>
+#include <crypto/hash_info.h>
 
 #include "ima.h"
 
@@ -35,11 +36,33 @@ int ima_appraise = IMA_APPRAISE_ENFORCE;
 int ima_appraise;
 #endif
 
-char *ima_hash = "sha1";
+int ima_hash_algo = HASH_ALGO_SHA1;
+static int hash_setup_done;
+
 static int __init hash_setup(char *str)
 {
-	if (strncmp(str, "md5", 3) == 0)
-		ima_hash = "md5";
+	struct ima_template_desc *template_desc = ima_template_desc_current();
+	int i;
+
+	if (hash_setup_done)
+		return 1;
+
+	if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
+		if (strncmp(str, "sha1", 4) == 0)
+			ima_hash_algo = HASH_ALGO_SHA1;
+		else if (strncmp(str, "md5", 3) == 0)
+			ima_hash_algo = HASH_ALGO_MD5;
+		goto out;
+	}
+
+	for (i = 0; i < HASH_ALGO__LAST; i++) {
+		if (strcmp(str, hash_algo_name[i]) == 0) {
+			ima_hash_algo = i;
+			break;
+		}
+	}
+out:
+	hash_setup_done = 1;
 	return 1;
 }
 __setup("ima_hash=", hash_setup);
@@ -48,20 +71,19 @@ __setup("ima_hash=", hash_setup);
  * ima_rdwr_violation_check
  *
  * Only invalidate the PCR for measured files:
- * 	- Opening a file for write when already open for read,
+ *	- Opening a file for write when already open for read,
  *	  results in a time of measure, time of use (ToMToU) error.
  *	- Opening a file for read when already open for write,
- * 	  could result in a file measurement error.
+ *	  could result in a file measurement error.
  *
  */
 static void ima_rdwr_violation_check(struct file *file)
 {
-	struct dentry *dentry = file->f_path.dentry;
-	struct inode *inode = dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	fmode_t mode = file->f_mode;
-	int must_measure;
 	bool send_tomtou = false, send_writers = false;
-	unsigned char *pathname = NULL, *pathbuf = NULL;
+	char *pathbuf = NULL;
+	const char *pathname;
 
 	if (!S_ISREG(inode->i_mode) || !ima_initialized)
 		return;
@@ -69,39 +91,30 @@ static void ima_rdwr_violation_check(struct file *file)
 	mutex_lock(&inode->i_mutex);	/* file metadata: permissions, xattr */
 
 	if (mode & FMODE_WRITE) {
-		if (atomic_read(&inode->i_readcount) && IS_IMA(inode))
-			send_tomtou = true;
-		goto out;
+		if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
+			struct integrity_iint_cache *iint;
+			iint = integrity_iint_find(inode);
+			/* IMA_MEASURE is set from reader side */
+			if (iint && (iint->flags & IMA_MEASURE))
+				send_tomtou = true;
+		}
+	} else {
+		if ((atomic_read(&inode->i_writecount) > 0) &&
+		    ima_must_measure(inode, MAY_READ, FILE_CHECK))
+			send_writers = true;
 	}
 
-	must_measure = ima_must_measure(inode, MAY_READ, FILE_CHECK);
-	if (!must_measure)
-		goto out;
-
-	if (atomic_read(&inode->i_writecount) > 0)
-		send_writers = true;
-out:
 	mutex_unlock(&inode->i_mutex);
 
 	if (!send_tomtou && !send_writers)
 		return;
 
-	/* We will allow 11 spaces for ' (deleted)' to be appended */
-	pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL);
-	if (pathbuf) {
-		pathname = d_path(&file->f_path, pathbuf, PATH_MAX + 11);
-		if (IS_ERR(pathname))
-			pathname = NULL;
-		else if (strlen(pathname) > IMA_EVENT_NAME_LEN_MAX)
-			pathname = NULL;
-	}
+	pathname = ima_d_path(&file->f_path, &pathbuf);
+
 	if (send_tomtou)
-		ima_add_violation(inode,
-				  !pathname ? dentry->d_name.name : pathname,
-				  "invalid_pcr", "ToMToU");
+		ima_add_violation(file, pathname, "invalid_pcr", "ToMToU");
 	if (send_writers)
-		ima_add_violation(inode,
-				  !pathname ? dentry->d_name.name : pathname,
+		ima_add_violation(file, pathname,
 				  "invalid_pcr", "open_writers");
 	kfree(pathbuf);
 }
@@ -132,7 +145,7 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint,
  */
 void ima_file_free(struct file *file)
 {
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct integrity_iint_cache *iint;
 
 	if (!iint_initialized || !S_ISREG(inode->i_mode))
@@ -145,25 +158,34 @@ void ima_file_free(struct file *file)
 	ima_check_last_writer(iint, inode, file);
 }
 
-static int process_measurement(struct file *file, const unsigned char *filename,
+static int process_measurement(struct file *file, const char *filename,
 			       int mask, int function)
 {
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct integrity_iint_cache *iint;
-	unsigned char *pathname = NULL, *pathbuf = NULL;
-	int rc = -ENOMEM, action, must_appraise;
+	struct ima_template_desc *template_desc = ima_template_desc_current();
+	char *pathbuf = NULL;
+	const char *pathname = NULL;
+	int rc = -ENOMEM, action, must_appraise, _func;
+	struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL;
+	int xattr_len = 0;
 
 	if (!ima_initialized || !S_ISREG(inode->i_mode))
 		return 0;
 
-	/* Determine if in appraise/audit/measurement policy,
-	 * returns IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT bitmask.  */
+	/* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
+	 * bitmask based on the appraise/audit/measurement policy.
+	 * Included is the appraise submask.
+	 */
 	action = ima_get_action(inode, mask, function);
 	if (!action)
 		return 0;
 
 	must_appraise = action & IMA_APPRAISE;
 
+	/*  Is the appraise rule hook specific?  */
+	_func = (action & IMA_FILE_APPRAISE) ? FILE_CHECK : function;
+
 	mutex_lock(&inode->i_mutex);
 
 	iint = integrity_inode_get(inode);
@@ -171,44 +193,53 @@ static int process_measurement(struct file *file, const unsigned char *filename,
 		goto out;
 
 	/* Determine if already appraised/measured based on bitmask
-	 * (IMA_MEASURE, IMA_MEASURED, IMA_APPRAISE, IMA_APPRAISED,
-	 *  IMA_AUDIT, IMA_AUDITED) */
+	 * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
+	 *  IMA_AUDIT, IMA_AUDITED)
+	 */
 	iint->flags |= action;
+	action &= IMA_DO_MASK;
 	action &= ~((iint->flags & IMA_DONE_MASK) >> 1);
 
 	/* Nothing to do, just return existing appraised status */
 	if (!action) {
-		if (iint->flags & IMA_APPRAISED)
-			rc = iint->ima_status;
-		goto out;
+		if (must_appraise)
+			rc = ima_get_cache_status(iint, _func);
+		goto out_digsig;
 	}
 
-	rc = ima_collect_measurement(iint, file);
-	if (rc != 0)
-		goto out;
+	if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
+		if (action & IMA_APPRAISE_SUBMASK)
+			xattr_ptr = &xattr_value;
+	} else
+		xattr_ptr = &xattr_value;
 
-	if (function != BPRM_CHECK) {
-		/* We will allow 11 spaces for ' (deleted)' to be appended */
-		pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL);
-		if (pathbuf) {
-			pathname =
-			    d_path(&file->f_path, pathbuf, PATH_MAX + 11);
-			if (IS_ERR(pathname))
-				pathname = NULL;
-		}
+	rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len);
+	if (rc != 0) {
+		if (file->f_flags & O_DIRECT)
+			rc = (iint->flags & IMA_PERMIT_DIRECTIO) ? 0 : -EACCES;
+		goto out_digsig;
 	}
+
+	pathname = filename ?: ima_d_path(&file->f_path, &pathbuf);
+
 	if (action & IMA_MEASURE)
-		ima_store_measurement(iint, file,
-				      !pathname ? filename : pathname);
-	if (action & IMA_APPRAISE)
-		rc = ima_appraise_measurement(iint, file,
-					      !pathname ? filename : pathname);
+		ima_store_measurement(iint, file, pathname,
+				      xattr_value, xattr_len);
+	if (action & IMA_APPRAISE_SUBMASK)
+		rc = ima_appraise_measurement(_func, iint, file, pathname,
+					      xattr_value, xattr_len);
 	if (action & IMA_AUDIT)
-		ima_audit_measurement(iint, !pathname ? filename : pathname);
+		ima_audit_measurement(iint, pathname);
 	kfree(pathbuf);
+out_digsig:
+	if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG))
+		rc = -EACCES;
 out:
 	mutex_unlock(&inode->i_mutex);
-	return (rc && must_appraise) ? -EACCES : 0;
+	kfree(xattr_value);
+	if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE))
+		return -EACCES;
+	return 0;
 }
 
 /**
@@ -219,19 +250,14 @@ out:
  * Measure files being mmapped executable based on the ima_must_measure()
  * policy decision.
  *
- * Return 0 on success, an error code on failure.
- * (Based on the results of appraise_measurement().)
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
  */
 int ima_file_mmap(struct file *file, unsigned long prot)
 {
-	int rc = 0;
-
-	if (!file)
-		return 0;
-	if (prot & PROT_EXEC)
-		rc = process_measurement(file, file->f_dentry->d_name.name,
-					 MAY_EXEC, FILE_MMAP);
-	return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+	if (file && (prot & PROT_EXEC))
+		return process_measurement(file, NULL, MAY_EXEC, MMAP_CHECK);
+	return 0;
 }
 
 /**
@@ -244,18 +270,15 @@ int ima_file_mmap(struct file *file, unsigned long prot)
  * So we can be certain that what we verify and measure here is actually
  * what is being executed.
  *
- * Return 0 on success, an error code on failure.
- * (Based on the results of appraise_measurement().)
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
  */
 int ima_bprm_check(struct linux_binprm *bprm)
 {
-	int rc;
-
-	rc = process_measurement(bprm->file,
-				 (strcmp(bprm->filename, bprm->interp) == 0) ?
-				 bprm->filename : bprm->interp,
-				 MAY_EXEC, BPRM_CHECK);
-	return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+	return process_measurement(bprm->file,
+				   (strcmp(bprm->filename, bprm->interp) == 0) ?
+				   bprm->filename : bprm->interp,
+				   MAY_EXEC, BPRM_CHECK);
 }
 
 /**
@@ -265,18 +288,15 @@ int ima_bprm_check(struct linux_binprm *bprm)
  *
  * Measure files based on the ima_must_measure() policy decision.
  *
- * Always return 0 and audit dentry_open failures.
- * (Return code will be based upon measurement appraisal.)
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
  */
 int ima_file_check(struct file *file, int mask)
 {
-	int rc;
-
 	ima_rdwr_violation_check(file);
-	rc = process_measurement(file, file->f_dentry->d_name.name,
-				 mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
-				 FILE_CHECK);
-	return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+	return process_measurement(file, NULL,
+				   mask & (MAY_READ | MAY_WRITE | MAY_EXEC),
+				   FILE_CHECK);
 }
 EXPORT_SYMBOL_GPL(ima_file_check);
 
@@ -286,29 +306,27 @@ EXPORT_SYMBOL_GPL(ima_file_check);
  *
  * Measure/appraise kernel modules based on policy.
  *
- * Always return 0 and audit dentry_open failures.
- * Return code is based upon measurement appraisal.
+ * On success return 0.  On integrity appraisal error, assuming the file
+ * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
  */
 int ima_module_check(struct file *file)
 {
-	int rc = 0;
-
 	if (!file) {
-		if (ima_appraise & IMA_APPRAISE_MODULES) {
 #ifndef CONFIG_MODULE_SIG_FORCE
-			rc = -EACCES;	/* INTEGRITY_UNKNOWN */
+		if ((ima_appraise & IMA_APPRAISE_MODULES) &&
+		    (ima_appraise & IMA_APPRAISE_ENFORCE))
+			return -EACCES;	/* INTEGRITY_UNKNOWN */
 #endif
-		}
-	} else
-		rc = process_measurement(file, file->f_dentry->d_name.name,
-					 MAY_EXEC, MODULE_CHECK);
-	return (ima_appraise & IMA_APPRAISE_ENFORCE) ? rc : 0;
+		return 0;	/* We rely on module signature checking */
+	}
+	return process_measurement(file, NULL, MAY_EXEC, MODULE_CHECK);
 }
 
 static int __init init_ima(void)
 {
 	int error;
 
+	hash_setup(CONFIG_IMA_DEFAULT_HASH);
 	error = ima_init();
 	if (!error)
 		ima_initialized = 1;