From b558a83a6235098560760fa59bf9a6b3da0d3aaa Mon Sep 17 00:00:00 2001
From: Roberto Sassu <roberto.sassu@huawei.com>
Date: Wed, 20 May 2020 09:35:15 +0200
Subject: [PATCH] Add option to set metadata for digest lists

---
 include/compact_list.h    |  2 +-
 lib/compact_list.c        | 74 ++++++++++++++++++++++++++++++---------
 src/upload_digest_lists.c |  4 +++
 3 files changed, 63 insertions(+), 17 deletions(-)

diff --git a/include/compact_list.h b/include/compact_list.h
index c8db246..51bd558 100644
--- a/include/compact_list.h
+++ b/include/compact_list.h
@@ -28,7 +28,7 @@ enum parser_ops { PARSER_OP_ADD_DIGEST, PARSER_OP_ADD_DIGEST_TO_HTABLE,
 		  PARSER_OP_ADD_EVM_XATTR,  PARSER_OP_REMOVE_EVM_XATTR,
 		  PARSER_OP_REMOVE_INFOFLOW_XATTR, PARSER_OP_VERIFY,
 		  PARSER_OP_DUMP, PARSER_OP_GEN_IMA_LIST, PARSER_OP_CHECK_META,
-		  PARSER_OP_REPAIR_META };
+		  PARSER_OP_REPAIR_META, PARSER_OP_REPAIR_META_DIGEST_LISTS };
 
 enum tlv_ids { ID_DIGEST, ID_EVM_DIGEST, ID_PATH, ID_INODE_UID, ID_INODE_GID,
 	       ID_INODE_MODE, ID_INODE_SIZE, ID_FSMAGIC, ID_OBJ_LABEL, ID_CAPS,
diff --git a/lib/compact_list.c b/lib/compact_list.c
index 5c1a1fd..c3ae07c 100644
--- a/lib/compact_list.c
+++ b/lib/compact_list.c
@@ -25,6 +25,7 @@
 #include <linux/fs.h>
 #include <linux/magic.h>
 #include <sys/capability.h>
+#include <selinux/selinux.h>
 
 #include "compact_list.h"
 #include "crypto.h"
@@ -35,6 +36,10 @@
 #include "ima_list.h"
 #include "selinux.h"
 
+#define DIGEST_LIST_LABEL "system_u:object_r:etc_t:s0"
+#define DIGEST_LIST_MODE 0644
+#define DIGEST_LIST_ALGO HASH_ALGO_SHA256
+
 char *compact_types_str[COMPACT__LAST] = {
 	[COMPACT_KEY] = "key",
 	[COMPACT_PARSER] = "parser",
@@ -610,18 +615,6 @@ out:
 	return ret;
 }
 
-int digest_list_update_evm_xattr(int dirfd, char *digest_list_filename)
-{
-	u8 evm_xattr_value = EVM_XATTR_HMAC;
-	int fd;
-
-	fd = openat(dirfd, digest_list_filename, O_RDONLY);
-	if (fd < 0)
-		return -EACCES;
-
-	return fsetxattr(fd, XATTR_NAME_EVM, &evm_xattr_value, 1, 0);
-}
-
 int digest_list_upload(int dirfd, int fd, struct list_head *head,
 		       struct list_head *parser_lib_head,
 		       char *digest_list_filename, enum parser_ops op,
@@ -690,8 +683,6 @@ out_add_metadata:
 		ret = digest_list_add_metadata(dirfd, fd, digest_list_filename,
 					       digest_lists_dir, head, buf,
 					       size);
-	else if (op == PARSER_OP_ADD_EVM_XATTR)
-		ret = digest_list_update_evm_xattr(dirfd, digest_list_filename);
 out:
 	munmap(buf, size);
 	return ret;
@@ -705,8 +696,12 @@ int process_lists(int dirfd, int fd, int save, int verbose,
 	struct dirent **digest_lists;
 	LIST_HEAD(parser_lib_head);
 	struct key_struct *k;
-	char path[PATH_MAX], *path_ptr = NULL;
-	int ret, i, n;
+	char path[PATH_MAX], path_sig[PATH_MAX], *path_ptr = NULL;
+	u8 digest[SHA512_DIGEST_SIZE];
+	u8 xattr[2 + SHA512_DIGEST_SIZE];
+	void *sig;
+	loff_t sig_len;
+	int ret, i, n, xattr_len;
 
 	n = scandirat(dirfd, ".", &digest_lists, filter[type], compare_lists);
 	if (n == -1) {
@@ -754,6 +749,53 @@ int process_lists(int dirfd, int fd, int save, int verbose,
 			ret = ima_generate_entry(dirfd, fd, digest_lists_dir,
 						 digest_lists[i]->d_name);
 			break;
+		case PARSER_OP_REPAIR_META_DIGEST_LISTS:
+			snprintf(path, sizeof(path), "%s/%s", digest_lists_dir,
+				 digest_lists[i]->d_name);
+			snprintf(path_sig, sizeof(path_sig), "%s.sig/%s.sig",
+				 digest_lists_dir, digest_lists[i]->d_name);
+
+			ret = read_file_from_path(-1, path_sig, &sig, &sig_len);
+			if (ret < 0)
+				break;
+
+			ret = lsetxattr(path, XATTR_NAME_EVM, sig, sig_len, 0);
+
+			munmap(sig, sig_len);
+
+			if (ret < 0) {
+				printf("Cannot set EVM xattr to %s\n", path);
+				break;
+			}
+
+			ret = lsetfilecon(path, DIGEST_LIST_LABEL);
+			if (ret < 0) {
+				printf("Cannot set SELinux label %s to %s\n",
+				       DIGEST_LIST_LABEL, path);
+				break;
+			}
+
+			ret = chmod(path, DIGEST_LIST_MODE);
+			if (ret < 0) {
+				printf("Cannot set mode %d to %s\n",
+				       DIGEST_LIST_MODE, path);
+				break;
+			}
+
+			ret = calc_file_digest(digest, -1, path,
+					       DIGEST_LIST_ALGO);
+			if (ret < 0) {
+				printf("Cannot calculate digest of %s\n", path);
+				break;
+			}
+
+			ret = gen_write_ima_xattr(xattr, &xattr_len, path,
+						  DIGEST_LIST_ALGO, digest,
+						  true, true);
+			if (ret < 0)
+				printf("Cannot set IMA xattr to %s\n", path);
+
+			break;
 		default:
 			if (backup_dir) {
 				snprintf(path, sizeof(path), "%s/%s",
diff --git a/src/upload_digest_lists.c b/src/upload_digest_lists.c
index 88aea1d..d618f01 100644
--- a/src/upload_digest_lists.c
+++ b/src/upload_digest_lists.c
@@ -166,6 +166,10 @@ int main(int argc, char *argv[])
 			} else if (!strcmp(optarg, "repair-meta")) {
 				op = PARSER_OP_REPAIR_META;
 				fd = -2;
+			} else if (!strcmp(optarg,
+					   "repair-meta-digest-lists")) {
+				op = PARSER_OP_REPAIR_META_DIGEST_LISTS;
+				fd = -2;
 			} else {
 				printf("Invalid parser op %s\n", optarg);
 				return 1;
-- 
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