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Known security limitations
--------------------------

Lack of secure memory wiping
============================

`Memory wiping`_ is used to protect secret data or key material from attackers
with access to uninitialized memory. This can be either because the attacker
has some kind of local user access or because of how other software uses
uninitialized memory.

Python exposes no API for us to implement this reliably and as such almost all
software in Python is potentially vulnerable to this attack. The
`CERT secure coding guidelines`_ assesses this issue as "Severity: medium,
Likelihood: unlikely, Remediation Cost: expensive to repair" and we do not
consider this a high risk for most users.

.. _`Memory wiping`:  http://blogs.msdn.com/b/oldnewthing/archive/2013/05/29/10421912.aspx
.. _`CERT secure coding guidelines`: https://www.securecoding.cert.org/confluence/display/c/MEM03-C.+Clear+sensitive+information+stored+in+reusable+resources
00DD; font-weight: bold } /* Literal.Number.Oct */ .highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */ .highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */ .highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */ .highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */ .highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */ .highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */ .highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */ .highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */ .highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */ .highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */ .highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */ .highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */ .highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */ .highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */ .highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */ .highlight .vc { color: #336699 } /* Name.Variable.Class */ .highlight .vg { color: #dd7700 } /* Name.Variable.Global */ .highlight .vi { color: #3333bb } /* Name.Variable.Instance */ .highlight .vm { color: #336699 } /* Name.Variable.Magic */ .highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
#
# Copyright (C) 2006-2010 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#

curdir:=package

include $(INCLUDE_DIR)/feeds.mk
include $(INCLUDE_DIR)/rootfs.mk

-include $(TMP_DIR)/.packagedeps
$(curdir)/autoremove:=1
$(curdir)/builddirs:=$(sort $(package-) $(package-y) $(package-m))
$(curdir)/builddirs-default:=. $(sort $(package-y) $(package-m))
$(curdir)/builddirs-prereq:=. $(sort $(prereq-y) $(prereq-m))
ifdef CHECK_ALL
$(curdir)/builddirs-check:=$($(curdir)/builddirs)
$(curdir)/builddirs-download:=$($(curdir)/builddirs)
endif
ifneq ($(IGNORE_ERRORS),)
  package-y-filter := $(package-y)
  package-m-filter := $(filter-out $(package-y),$(package-m))
  package-n-filter := $(filter-out $(package-y) $(package-m),$(package-))
  package-ignore-errors := $(filter n m y,$(IGNORE_ERRORS))
  package-ignore-errors := $(if $(package-ignore-errors),$(package-ignore-errors),n m)
  package-ignore-subdirs := $(sort $(foreach m,$(package-ignore-errors),$(package-$(m)-filter)))
  $(curdir)/builddirs-ignore-download := $(package-ignore-subdirs)
  $(curdir)/builddirs-ignore-compile := $(package-ignore-subdirs)
  $(curdir)/builddirs-ignore-host-download := $(package-ignore-subdirs)
  $(curdir)/builddirs-ignore-host-compile := $(package-ignore-subdirs)
endif

PACKAGE_INSTALL_FILES:= \
	$(foreach pkg,$(sort $(package-y)), \
		$(foreach variant, \
			$(if $(strip $(package/$(pkg)/variants)), \
				$(package/$(pkg)/variants), \
				$(if $(package/$(pkg)/default-variant), \
					$(package/$(pkg)/default-variant), \
					default \
				) \
			), \
			$(PKG_INFO_DIR)/$(lastword $(subst /,$(space),$(pkg))).$(variant).install \
		) \
	)

$(curdir)/cleanup: $(TMP_DIR)/.build
	rm -rf $(STAGING_DIR_ROOT)

$(curdir)/merge:
	rm -rf $(PACKAGE_DIR_ALL)
	mkdir -p $(PACKAGE_DIR_ALL)
	-$(foreach pdir,$(PACKAGE_SUBDIRS),$(if $(wildcard $(pdir)/*.ipk),ln -s $(pdir)/*.ipk $(PACKAGE_DIR_ALL);))

$(curdir)/merge-index: $(curdir)/merge
	(cd $(PACKAGE_DIR_ALL) && $(SCRIPT_DIR)/ipkg-make-index.sh . 2>&1 > Packages; )

ifndef SDK
  $(curdir)/compile: $(curdir)/system/opkg/host/compile
endif

$(curdir)/install: $(TMP_DIR)/.build $(curdir)/merge $(if $(CONFIG_TARGET_PER_DEVICE_ROOTFS),$(curdir)/merge-index)
	- find $(STAGING_DIR_ROOT) -type d | $(XARGS) chmod 0755
	rm -rf $(TARGET_DIR) $(TARGET_DIR_ORIG)
	mkdir -p $(TARGET_DIR)/tmp
	$(call opkg,$(TARGET_DIR)) install \
		$(call opkg_package_files,$(foreach pkg,$(shell cat $(PACKAGE_INSTALL_FILES) 2>/dev/null),$(pkg)$(call GetABISuffix,$(pkg))))
	@for file in $(PACKAGE_INSTALL_FILES); do \
		[ -s $$file.flags ] || continue; \
		for flag in `cat $$file.flags`; do \
			$(call opkg,$(TARGET_DIR)) flag $$flag `cat $$file`; \
		done; \
	done || true

	$(CP) $(TARGET_DIR) $(TARGET_DIR_ORIG)

	$(call prepare_rootfs,$(TARGET_DIR),$(TOPDIR)/files)

$(curdir)/index: FORCE
	@echo Generating package index...
	@for d in $(PACKAGE_SUBDIRS); do ( \
		mkdir -p $$d; \
		cd $$d || continue; \
		$(SCRIPT_DIR)/ipkg-make-index.sh . 2>&1 > Packages.manifest; \
		grep -vE '^(Maintainer|LicenseFiles|Source|SourceName|Require)' Packages.manifest > Packages && \
			gzip -9nc Packages > Packages.gz; \
	); done
ifdef CONFIG_SIGNED_PACKAGES
	@echo Signing package index...
	@for d in $(PACKAGE_SUBDIRS); do ( \
		[ -d $$d ] && \
			cd $$d || continue; \
		$(STAGING_DIR_HOST)/bin/usign -S -m Packages -s $(BUILD_KEY); \
	); done
endif

$(curdir)/flags-install:= -j1

$(eval $(call stampfile,$(curdir),package,prereq,.config))
$(eval $(call stampfile,$(curdir),package,cleanup,$(TMP_DIR)/.build))
$(eval $(call stampfile,$(curdir),package,compile,$(TMP_DIR)/.build))
$(eval $(call stampfile,$(curdir),package,install,$(TMP_DIR)/.build))
$(eval $(call stampfile,$(curdir),package,check,$(TMP_DIR)/.build))

$(eval $(call subdir,$(curdir)))