audit: sanitize --system

make the system audit compare only installed files, instead of
scanning the whole file system. also make it print only package
names with -q, so reinstalling modified packages becomes easy.

src/audit.c

@@ -18,31 +18,39 @@
 #include "apk_applet.h"
 #include "apk_database.h"
 
-#define AUDIT_BACKUP BIT(0)
-#define AUDIT_SYSTEM BIT(1)
-
 struct audit_ctx {
-	int type;
-	struct apk_database *db;
+	int (*audit)(struct apk_database *db);
 };
 
+static int audit_file(struct apk_database *db, struct apk_db_file *dbf,
+		      const char *name)
+{
+	struct apk_file_info fi;
+
+	if (apk_file_get_info(db->root_fd, name, dbf->csum.type, &fi) != 0)
+		return 1;
+
+	if (dbf->csum.type != APK_CHECKSUM_NONE &&
+	    apk_checksum_compare(&fi.csum, &dbf->csum) == 0)
+		return 0;
+
+	if (S_ISLNK(fi.mode) && dbf->csum.type == APK_CHECKSUM_NONE)
+		return 0;
+
+	return 1;
+}
+
 static int audit_directory(apk_hash_item item, void *ctx)
 {
+	struct apk_database *db = (struct apk_database *) ctx;
 	struct apk_db_dir *dbd = (struct apk_db_dir *) item;
 	struct apk_db_file *dbf;
-	struct audit_ctx *actx = (struct audit_ctx *) ctx;
-	struct apk_database *db = actx->db;
-	struct dirent *de;
 	struct apk_file_info fi;
+	struct dirent *de;
 	apk_blob_t bdir = APK_BLOB_PTR_LEN(dbd->name, dbd->namelen);
-	char tmp[512], reason;
+	char tmp[PATH_MAX], reason;
 	DIR *dir;
 
-	if (!(actx->type & AUDIT_SYSTEM) && !(dbd->flags & APK_DBDIRF_PROTECTED))
-		return 0;
-	if (!(actx->type & AUDIT_BACKUP) && (dbd->flags & APK_DBDIRF_PROTECTED))
-		return 0;
-
 	dir = fdopendir(openat(db->root_fd, dbd->name, O_RDONLY));
 	if (dir == NULL)
 		return 0;
@@ -57,8 +65,7 @@ static int audit_directory(apk_hash_item item, void *ctx)
 		if (apk_file_get_info(db->root_fd, tmp, APK_CHECKSUM_NONE, &fi) < 0)
 			continue;
 
-		if (!(actx->type & AUDIT_SYSTEM) &&
-		    (dbd->flags & APK_DBDIRF_SYMLINKS_ONLY) &&
+		if ((dbd->flags & APK_DBDIRF_SYMLINKS_ONLY) &&
 		    !S_ISLNK(fi.mode))
 			continue;
 
@@ -70,23 +77,66 @@ static int audit_directory(apk_hash_item item, void *ctx)
 		} else {
 			dbf = apk_db_file_query(db, bdir, APK_BLOB_STR(de->d_name));
 			if (dbf != NULL) {
-				if (dbf->csum.type != APK_CHECKSUM_NONE &&
-				    apk_file_get_info(db->root_fd, tmp, dbf->csum.type, &fi) == 0 &&
-				    apk_checksum_compare(&fi.csum, &dbf->csum) == 0)
+				if (audit_file(db, dbf, tmp) == 0)
 					continue;
-
 				reason = 'U';
 			} else {
 				reason = 'A';
 			}
 		}
+
 		if (apk_verbosity < 1)
 			printf("%s\n", tmp);
 		else
 			printf("%c %s\n", reason, tmp);
 	}
-
 	closedir(dir);
+
+	return 0;
+}
+
+static int audit_backup(struct apk_database *db)
+{
+	return apk_hash_foreach(&db->installed.dirs, audit_directory, &db);
+}
+
+static int audit_system(struct apk_database *db)
+{
+	struct apk_package *pkg;
+	struct apk_db_dir_instance *diri;
+	struct apk_db_file *file;
+	struct hlist_node *dn, *fn;
+	char name[PATH_MAX];
+	int done;
+
+	list_for_each_entry(pkg, &db->installed.packages, installed_pkgs_list) {
+		hlist_for_each_entry(diri, dn, &pkg->owned_dirs, pkg_dirs_list) {
+			if (diri->dir->flags & APK_DBDIRF_PROTECTED)
+				continue;
+
+			done = 0;
+			hlist_for_each_entry(file, fn, &diri->owned_files,
+					     diri_files_list) {
+
+				snprintf(name, sizeof(name), "%s/%s",
+					 diri->dir->name, file->name);
+
+				if (audit_file(db, file, name) == 0)
+					continue;
+
+				if (apk_verbosity < 1) {
+					printf("%s\n", pkg->name->name);
+					done = 1;
+					break;
+				}
+
+				printf("M %s\n", name);
+			}
+			if (done)
+				break;
+		}
+	}
+
 	return 0;
 }
 
@@ -96,10 +146,10 @@ static int audit_parse(void *ctx, int optch, int optindex, const char *optarg)
 
 	switch (optch) {
 	case 0x10000:
-		actx->type |= AUDIT_BACKUP;
+		actx->audit = audit_backup;
 		break;
 	case 0x10001:
-		actx->type |= AUDIT_SYSTEM;
+		actx->audit = audit_system;
 		break;
 	default:
 		return -1;
@@ -113,28 +163,25 @@ static int audit_main(void *ctx, int argc, char **argv)
 	struct apk_database db;
 	int r;
 
-	if (actx->type == 0)
+	if (actx->audit == NULL)
 		return -EINVAL;
 
 	r = apk_db_open(&db, apk_root, APK_OPENF_READ);
 	if (r != 0) {
 		apk_error("APK database not present");
-		return 1;
+		return r;
 	}
-
-	actx->db = &db;
-
-	fchdir(db.root_fd);
-	r = apk_hash_foreach(&db.installed.dirs, audit_directory, actx);
-
+	r = actx->audit(&db);
 	apk_db_close(&db);
+
 	return r;
 }
 
 static struct apk_option audit_options[] = {
 	{ 0x10000, "backup",
 	  "List all modified configuration files that need to be backed up" },
-	{ 0x10001, "system", "List all modified non-protected files" },
+	{ 0x10001, "system", "Verify checksums of all installed files "
+		             "(-q to print only modfied packages)" },
 };
 
 static struct apk_applet apk_audit = {