1 files changed, 357 insertions, 0 deletions

diff --git a/src/app_audit.c b/src/app_audit.c
new file mode 100644
index 0000000..696599b
--- /dev/null
+++ b/src/app_audit.c
@@ -0,0 +1,357 @@
+/* app_audit.c - Alpine Package Keeper (APK)
+ *
+ * Copyright (C) 2005-2008 Natanael Copa <n@tanael.org>
+ * Copyright (C) 2008-2011 Timo Teräs <timo.teras@iki.fi>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation. See http://www.gnu.org/ for details.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fnmatch.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include "apk_applet.h"
+#include "apk_database.h"
+#include "apk_print.h"
+
+/* Use (unused) highest bit of mode_t as seen flag of our internal
+ * database file entries */
+#define S_SEENFLAG	0x80000000
+
+enum {
+	MODE_BACKUP = 0,
+	MODE_SYSTEM
+};
+
+struct audit_ctx {
+	unsigned mode : 1;
+	unsigned recursive : 1;
+	unsigned check_permissions : 1;
+	unsigned packages_only : 1;
+};
+
+static int option_parse_applet(void *ctx, struct apk_db_options *dbopts, int optch, const char *optarg)
+{
+	struct audit_ctx *actx = (struct audit_ctx *) ctx;
+
+	switch (optch) {
+	case 0x10000:
+		actx->mode = MODE_BACKUP;
+		break;
+	case 0x10001:
+		actx->mode = MODE_SYSTEM;
+		break;
+	case 0x10002:
+		actx->check_permissions = 1;
+		break;
+	case 0x10003:
+		actx->packages_only = 1;
+		break;
+	case 'r':
+		actx->recursive = 1;
+		break;
+	default:
+		return -ENOTSUP;
+	}
+	return 0;
+}
+
+static const struct apk_option options_applet[] = {
+	{ 0x10000, "backup" },
+	{ 0x10001, "system" },
+	{ 0x10002, "check-permissions" },
+	{ 'r', "recursive" },
+	{ 0x10003, "packages" },
+};
+
+static const struct apk_option_group optgroup_applet = {
+	.name = "Audit",
+	.options = options_applet,
+	.num_options = ARRAY_SIZE(options_applet),
+	.parse = option_parse_applet,
+};
+
+struct audit_tree_ctx {
+	struct audit_ctx *actx;
+	struct apk_database *db;
+	struct apk_db_dir *dir;
+	size_t pathlen;
+	char path[PATH_MAX];
+};
+
+static int audit_file(struct audit_ctx *actx,
+		      struct apk_database *db,
+		      struct apk_db_file *dbf,
+		      int dirfd, const char *name)
+{
+	struct apk_file_info fi;
+	int rv = 0;
+
+	if (dbf == NULL)
+		return 'A';
+
+	dbf->audited = 1;
+
+	if (apk_fileinfo_get(dirfd, name,
+				APK_FI_NOFOLLOW |
+				APK_FI_XATTR_CSUM(dbf->acl->xattr_csum.type ?: APK_CHECKSUM_DEFAULT) |
+				APK_FI_CSUM(dbf->csum.type),
+				&fi) != 0)
+		return -EPERM;
+
+	if (dbf->csum.type != APK_CHECKSUM_NONE &&
+	    apk_checksum_compare(&fi.csum, &dbf->csum) != 0)
+		rv = 'U';
+	else if (!S_ISLNK(fi.mode) && !dbf->diri->pkg->ipkg->broken_xattr &&
+	         apk_checksum_compare(&fi.xattr_csum, &dbf->acl->xattr_csum) != 0)
+		rv = 'x';
+	else if (S_ISLNK(fi.mode) && dbf->csum.type == APK_CHECKSUM_NONE)
+		rv = 'U';
+	else if (actx->check_permissions) {
+		if ((fi.mode & 07777) != (dbf->acl->mode & 07777))
+			rv = 'M';
+		else if (fi.uid != dbf->acl->uid || fi.gid != dbf->acl->gid)
+			rv = 'M';
+	}
+	apk_fileinfo_free(&fi);
+
+	return rv;
+}
+
+static int audit_directory(struct audit_ctx *actx,
+			   struct apk_database *db,
+			   struct apk_db_dir *dbd,
+			   struct apk_file_info *fi)
+{
+	if (dbd != NULL) dbd->mode |= S_SEENFLAG;
+
+	if (dbd == NULL || dbd->refs == 1)
+		return actx->recursive ? 'd' : 'D';
+
+	if (actx->check_permissions &&
+	    ((dbd->mode & ~S_SEENFLAG) || dbd->uid || dbd->gid)) {
+		if ((fi->mode & 07777) != (dbd->mode & 07777))
+			return 'm';
+		if (fi->uid != dbd->uid || fi->gid != dbd->gid)
+			return 'm';
+	}
+
+	return 0;
+}
+
+static void report_audit(struct audit_ctx *actx,
+			 char reason, apk_blob_t bfull, struct apk_package *pkg)
+{
+	if (!reason)
+		return;
+
+	if (actx->packages_only) {
+		if (pkg == NULL || pkg->state_int != 0)
+			return;
+		pkg->state_int = 1;
+		if (apk_verbosity < 1)
+			printf("%s\n", pkg->name->name);
+		else
+			printf(PKG_VER_FMT "\n", PKG_VER_PRINTF(pkg));
+	} else if (apk_verbosity < 1) {
+		printf(BLOB_FMT "\n", BLOB_PRINTF(bfull));
+	} else
+		printf("%c " BLOB_FMT "\n", reason, BLOB_PRINTF(bfull));
+}
+
+static int audit_directory_tree_item(void *ctx, int dirfd, const char *name)
+{
+	struct audit_tree_ctx *atctx = (struct audit_tree_ctx *) ctx;
+	apk_blob_t bdir = APK_BLOB_PTR_LEN(atctx->path, atctx->pathlen);
+	apk_blob_t bent = APK_BLOB_STR(name);
+	apk_blob_t bfull;
+	struct audit_ctx *actx = atctx->actx;
+	struct apk_database *db = atctx->db;
+	struct apk_db_dir *dir = atctx->dir, *child = NULL;
+	struct apk_file_info fi;
+	int reason = 0;
+
+	if (bdir.len + bent.len + 1 >= sizeof(atctx->path)) return 0;
+	if (apk_fileinfo_get(dirfd, name, APK_FI_NOFOLLOW, &fi) < 0) return 0;
+
+	memcpy(&atctx->path[atctx->pathlen], bent.ptr, bent.len);
+	atctx->pathlen += bent.len;
+	bfull = APK_BLOB_PTR_LEN(atctx->path, atctx->pathlen);
+
+	if (S_ISDIR(fi.mode)) {
+		int recurse = TRUE;
+
+		if (actx->mode == MODE_BACKUP) {
+			child = apk_db_dir_get(db, bfull);
+			if (!child->has_protected_children)
+				recurse = FALSE;
+			if (child->protect_mode == APK_PROTECT_NONE)
+				goto recurse_check;
+		} else {
+			child = apk_db_dir_query(db, bfull);
+			if (child == NULL)
+				goto done;
+			child = apk_db_dir_ref(child);
+		}
+
+		reason = audit_directory(actx, db, child, &fi);
+		if (reason < 0)
+			goto done;
+
+recurse_check:
+		atctx->path[atctx->pathlen++] = '/';
+		bfull.len++;
+		report_audit(actx, reason, bfull, NULL);
+		if (reason != 'D' && recurse) {
+			atctx->dir = child;
+			reason = apk_dir_foreach_file(
+				openat(dirfd, name, O_RDONLY|O_CLOEXEC),
+				audit_directory_tree_item, atctx);
+			atctx->dir = dir;
+		}
+		bfull.len--;
+		atctx->pathlen--;
+	} else {
+		struct apk_db_file *dbf;
+		struct apk_protected_path *ppath;
+		int protect_mode = dir->protect_mode;
+
+		/* inherit file's protection mask */
+		foreach_array_item(ppath, dir->protected_paths) {
+			char *slash = strchr(ppath->relative_pattern, '/');
+			if (slash == NULL) {
+				if (fnmatch(ppath->relative_pattern, name, FNM_PATHNAME) != 0)
+					continue;
+				protect_mode = ppath->protect_mode;
+			}
+		}
+
+		if (actx->mode == MODE_BACKUP) {
+			switch (protect_mode) {
+			case APK_PROTECT_NONE:
+				goto done;
+			case APK_PROTECT_CHANGED:
+				break;
+			case APK_PROTECT_SYMLINKS_ONLY:
+				if (!S_ISLNK(fi.mode))
+					goto done;
+				break;
+			case APK_PROTECT_ALL:
+				reason = 'A';
+				break;
+			}
+		}
+
+		dbf = apk_db_file_query(db, bdir, bent);
+		if (reason == 0)
+			reason = audit_file(actx, db, dbf, dirfd, name);
+		if (reason < 0)
+			goto done;
+		if (actx->mode == MODE_SYSTEM &&
+		    (reason == 'A' || protect_mode != APK_PROTECT_NONE))
+			goto done;
+		if (actx->mode == MODE_BACKUP &&
+		    reason == 'A' &&
+		    apk_blob_ends_with(bent, APK_BLOB_STR(".apk-new")))
+			goto done;
+		report_audit(actx, reason, bfull, dbf ? dbf->diri->pkg : NULL);
+	}
+
+done:
+	if (child)
+		apk_db_dir_unref(db, child, FALSE);
+
+	atctx->pathlen -= bent.len;
+	return 0;
+}
+
+static int audit_directory_tree(struct audit_tree_ctx *atctx, int dirfd)
+{
+	apk_blob_t path;
+	int r;
+
+	path = APK_BLOB_PTR_LEN(atctx->path, atctx->pathlen);
+	if (path.len && path.ptr[path.len-1] == '/')
+		path.len--;
+
+	atctx->dir = apk_db_dir_get(atctx->db, path);
+	atctx->dir->mode |= S_SEENFLAG;
+	r = apk_dir_foreach_file(dirfd, audit_directory_tree_item, atctx);
+	apk_db_dir_unref(atctx->db, atctx->dir, FALSE);
+
+	return r;
+}
+
+static int audit_missing_files(apk_hash_item item, void *pctx)
+{
+	struct audit_ctx *actx = pctx;
+	struct apk_db_file *file = item;
+	struct apk_db_dir *dir;
+	char path[PATH_MAX];
+	int len;
+
+	if (file->audited) return 0;
+
+	dir = file->diri->dir;
+	if (dir->mode & S_SEENFLAG) {
+		len = snprintf(path, sizeof(path), DIR_FILE_FMT, DIR_FILE_PRINTF(dir, file));
+		report_audit(actx, 'X', APK_BLOB_PTR_LEN(path, len), file->diri->pkg);
+	}
+
+	return 0;
+}
+
+static int audit_main(void *ctx, struct apk_database *db, struct apk_string_array *args)
+{
+	struct audit_tree_ctx atctx;
+	struct audit_ctx *actx = (struct audit_ctx *) ctx;
+	char **parg, *arg;
+	int r = 0;
+
+	atctx.db = db;
+	atctx.actx = actx;
+	atctx.pathlen = 0;
+	atctx.path[0] = 0;
+
+	if (args->num == 0) {
+		r |= audit_directory_tree(&atctx, dup(db->root_fd));
+	} else {
+		foreach_array_item(parg, args) {
+			arg = *parg;
+			if (arg[0] != '/') {
+				apk_warning("%s: relative path skipped.\n", arg);
+				continue;
+			}
+			arg++;
+			atctx.pathlen = strlen(arg);
+			memcpy(atctx.path, arg, atctx.pathlen);
+			if (atctx.path[atctx.pathlen-1] != '/')
+				atctx.path[atctx.pathlen++] = '/';
+
+			r |= audit_directory_tree(&atctx, openat(db->root_fd, arg, O_RDONLY|O_CLOEXEC));
+		}
+	}
+	if (actx->mode == MODE_SYSTEM)
+		apk_hash_foreach(&db->installed.files, audit_missing_files, ctx);
+
+	return r;
+}
+
+static struct apk_applet apk_audit = {
+	.name = "audit",
+	.arguments = "[directory to audit]...",
+	.open_flags = APK_OPENF_READ|APK_OPENF_NO_SCRIPTS|APK_OPENF_NO_REPOS,
+	.context_size = sizeof(struct audit_ctx),
+	.optgroups = { &optgroup_global, &optgroup_applet },
+	.main = audit_main,
+};
+
+APK_DEFINE_APPLET(apk_audit);
+