Merge pull request #1676 from t-koulouris/theo_pr

Numerous fixes and updates for the okernel project
2025-07-23 02:51:55 +00:00 · 2017-04-20 11:22:33 -05:00 · 2017-04-20 11:22:33 -05:00 · 90d459a82e
commit 90d459a82e
parent fc1e7e4ca5 f1508901f4
5 changed files with 2982 additions and 1197 deletions
--- a/projects/okernel/Dockerfile.okernel
+++ b/projects/okernel/Dockerfile.okernel
@ -1,20 +1,21 @@
 FROM linuxkit/alpine-build-kernel:cfdd576c36a52ed2dd62f237f79eeedc2dd3697b@sha256:3fe08db373a9373ba1616a485858f01ebd2d7a3cb364a099d0ed8b45fa419da2

-#ARG KERNEL_PREFIX
 ARG KERNEL_VERSION
 ARG DEBUG=0
-ARG PROXY
-
-#ENV KERNEL_SOURCE=https://github.com/linux-okernel/linux-okernel/archive/ok-${KERNEL_VERSION}.tar.gz
-ENV KERNEL_SOURCE=https://github.com/linux-okernel/linux-okernel/archive/linux-okernel.tar.gz

+ENV OKERNEL_SOURCE=https://github.com/linux-okernel/linux-okernel/archive/${KERNEL_VERSION}.tar.gz
 ENV USPACE_SOURCE=https://github.com/linux-okernel/linux-okernel-components/archive/master.tar.gz

-RUN curl -fsSL -x ${PROXY} -o linux-${KERNEL_VERSION}.tar.gz ${KERNEL_SOURCE}
+RUN apk --update add openssl openssl-dev

-RUN cat linux-${KERNEL_VERSION}.tar.gz | tar --absolute-names -xz && mv /linux-okernel-linux-okernel /linux
+RUN if [ -n $HTTP_PROXY ]; then \
+    curl -fsSL -x ${HTTP_PROXY} -o linux-${KERNEL_VERSION}.tar.gz ${OKERNEL_SOURCE}; \
+    else \
+    curl -fsSL -o linux-${KERNEL_VERSION}.tar.gz ${OKERNEL_SOURCE}; \
+    fi
+
+RUN cat linux-${KERNEL_VERSION}.tar.gz | tar --absolute-names -xz && mv /linux-okernel-${KERNEL_VERSION} /linux

-# NOTE: This currently re-uses the 4.9 kernel config with CONFIG_OKERNEL set
 COPY kernel_config.okernel /linux/arch/x86/configs/x86_64_defconfig
 #COPY kernel_config.debug /linux/debug_config

@ -57,17 +58,23 @@ RUN DVER=$(basename $(find /tmp/kernel-modules/lib/modules/ -mindepth 1 -maxdept
    mkdir -p "$dir"/arch/x86 && cp -a arch/x86/include "$dir"/arch/x86/ && \
    ( cd /tmp && tar cf /kernel-dev.tar usr/src )

-RUN printf "KERNEL_SOURCE=${KERNEL_SOURCE}\n" > /kernel-source-info
+RUN printf "KERNEL_SOURCE=${OKERNEL_SOURCE}\n" > /kernel-source-info

 # Build kernel module from linux-okernel-components
-RUN curl -fsSL -x ${PROXY} -o okernel-userspace.tar.gz ${USPACE_SOURCE}
+RUN if [ -n $HTTP_PROXY ]; then \
+    curl -fsSL -x ${HTTP_PROXY} -o okernel-userspace.tar.gz ${USPACE_SOURCE}; \
+    else \
+    curl -fsSL -o okernel-userspace.tar.gz ${USPACE_SOURCE}; \
+    fi

 RUN cat okernel-userspace.tar.gz | tar --absolute-names -xz && mv /linux-okernel-components-master /ok_components

 WORKDIR /ok_components/test_mappings/kvmod
-RUN sed -i 's_~/linux-okernel_/linux_' Makefile
-RUN make
-RUN mkdir -p /tmp/root/kvmod && cp kernel_vuln.ko /tmp/root/kvmod
-WORKDIR /tmp
-RUN tar cf /kernel_vuln.tar root
+
+RUN sed -i 's_~/linux-okernel_/linux_' Makefile && \
+    make && \
+    mkdir -p /tmp/root/kvmod && cp kernel_vuln.ko /tmp/root/kvmod && \
+    cd /tmp && \
+    tar cf /kernel_vuln.tar root
+
 WORKDIR /
--- a/projects/okernel/Makefile
+++ b/projects/okernel/Makefile
@ -3,9 +3,9 @@ DEBUG ?= 0
 all:	bzImage tag

 # We push the image to hub twice, once with the full kernel version of
-# "mobylinux/kernel:<kernel version>.<major version>.<minor version>-<n>",
+# "linuxkit/kernel:<kernel version>.<major version>.<minor version>-<n>",
 # where "<n>" is a monotonically increasing config number, and as
-# "mobylinux/kernel:<kernel version>.<major version>.x". This version
+# "linuxkit/kernel:<kernel version>.<major version>.x". This version
 # number is stored in IMAGE_VERSION.
 #
 # We expect most users to us the "<kernel version>.<major version>.x"
@ -19,16 +19,29 @@ all:	bzImage tag
 #
 # IMAGE_VERSION is used to determine if a new image should be pushed to hub.

-KERNEL_VERSION=4.11-rc4
+ifdef KERNEL
+ifneq ($(KERNEL),latest)
+KERNEL_VERSION=$(KERNEL)
 IMAGE_VERSION=$(KERNEL_VERSION)-0
+else
+KERNEL_VERSION=linux-okernel
+IMAGE_VERSION=latest
+endif
+else
+KERNEL_VERSION=linux-okernel
+IMAGE_VERSION=latest
+endif
+
+IMAGE=okernel
 IMAGE_MAJOR_VERSION=4.11.x
 DEPS=Dockerfile.okernel Makefile kernel_config.okernel Dockerfile.kvmod

-PROXY_URL=$(HTTP_PROXY)
+MEDIA_TOYBOX=linuxkit/toybox-media:d7e82a7d19ccc84c9071fa7a88ecaa58ae958f7c@sha256:4c7d25f2be2429cd08417c36e04161cb924e46f3e419ee33a0aa9ff3a0942e02
+

 kernel.tag: $(DEPS)
-ifdef PROXY_URL
-	BUILD=$$( tar cf - $^ | docker build -f $< --build-arg DEBUG=$(DEBUG) --build-arg KERNEL_VERSION=$(KERNEL_VERSION) --build-arg PROXY=$(PROXY_URL) -q - ) && [ -n "$$BUILD" ] && echo "Built $$BUILD" && echo "$$BUILD" > $@
+ifdef HTTP_PROXY
+	BUILD=$$( tar cf - $^ | docker build -f $< --build-arg DEBUG=$(DEBUG) --build-arg KERNEL_VERSION=$(KERNEL_VERSION) --build-arg HTTP_PROXY=$(HTTP_PROXY) -q - ) && [ -n "$$BUILD" ] && echo "Built $$BUILD" && echo "$$BUILD" > $@
 else
 	BUILD=$$( tar cf - $^ | docker build -f $< --build-arg DEBUG=$(DEBUG) --build-arg KERNEL_VERSION=$(KERNEL_VERSION) -q - ) && [ -n "$$BUILD" ] && echo "Built $$BUILD" && echo "$$BUILD" > $@
 endif
@ -42,34 +55,31 @@ bzImage: kernel.tag
 	tar xf kernel_vuln.tar -C kvmod
 	cp x86_64/bzImage $@

-.PHONY: image push tag
-
-MEDIA_TOYBOX=linuxkit/toybox-media:d7e82a7d19ccc84c9071fa7a88ecaa58ae958f7c@sha256:4c7d25f2be2429cd08417c36e04161cb924e46f3e419ee33a0aa9ff3a0942e02
-
-#BASE="$MEDIA_TOYBOX"
-IMAGE=kernel
+.PHONY: image push tag kvmod

 default: push

 Dockerfile.media:
-	printf "FROM $(MEDIA_TOYBOX)\nADD . /\n" > $@
+	printf "FROM $(MEDIA_TOYBOX)\nCOPY bzImage kernel.tar /\n" > $@

 image: Dockerfile.media bzImage kernel.tar Dockerfile.kvmod kvmod/root/kvmod/kernel_vuln.ko $(DEPS)
 	tar cf - $^ | docker build --no-cache -t $(IMAGE):build -f Dockerfile.media -
-	tar cf - $^ | docker build --no-cache -t ok-kvmod:$(IMAGE_VERSION) -f Dockerfile.kvmod -
+
+kvmod: Dockerfile.kvmod kvmod/root/kvmod/kernel_vuln.ko $(DEPS)
+	tar cf - $^ | docker build --no-cache -t okernel-kvmod:$(IMAGE_VERSION) -f Dockerfile.kvmod -

 push: image
-	docker pull mobylinux/$(IMAGE):$(IMAGE_VERSION) || \
-		(docker tag $(IMAGE):build mobylinux/$(IMAGE):$(IMAGE_VERSION) && \
-		 docker push mobylinux/$(IMAGE):$(IMAGE_VERSION) && \
-		 docker tag $(IMAGE):build mobylinux/$(IMAGE):$(IMAGE_MAJOR_VERSION) && \
-		 docker push mobylinux/$(IMAGE):$(IMAGE_MAJOR_VERSION))
+	docker pull linuxkit/$(IMAGE):$(IMAGE_VERSION) || \
+		(docker tag $(IMAGE):build linuxkit/$(IMAGE):$(IMAGE_VERSION) && \
+		 docker push linuxkit/$(IMAGE):$(IMAGE_VERSION) && \
+		 docker tag $(IMAGE):build linuxkit/$(IMAGE):$(IMAGE_MAJOR_VERSION) && \
+		 docker push linuxkit/$(IMAGE):$(IMAGE_MAJOR_VERSION))
 	docker rmi $(IMAGE):build
 	rm -f hash

 tag: image
-	(docker tag $(IMAGE):build mobylinux/$(IMAGE):$(IMAGE_VERSION) && \
-	docker tag $(IMAGE):build mobylinux/$(IMAGE):$(IMAGE_MAJOR_VERSION))
+	(docker tag $(IMAGE):build linuxkit/$(IMAGE):$(IMAGE_VERSION) && \
+	docker tag $(IMAGE):build linuxkit/$(IMAGE):$(IMAGE_MAJOR_VERSION))
 	docker rmi $(IMAGE):build
 	rm -f hash

--- a/projects/okernel/README.md
+++ b/projects/okernel/README.md
@ -1,19 +1,25 @@
-Authors: Chris Dalton <cid@hpi.com>, Nigel Edwards <nigel.edwards@hpe.com>
+Authors: Chris Dalton <cid@hpi.com>, Nigel Edwards <nigel.edwards@hpe.com>,
+Theo Koulouris <theo.koulouris@hpe.com>

 # Split Kernel

-Similar to the nested-kernel work for BSD by Dautenhan[1], the aim of
-the split kernel is to introduce a level of intra-kernel protection
-into the kernel so that, amongst other things, we can offer lifetime
-guarantees over kernel code and data integrity.  Unlike the BSD-based
-nested kernel work we are focused on the Linux kernel not BSD and do
-make use of HW virtualization features such as Extended Page Tables
+Project links:
+- okernel sources on GitHub: https://github.com/linux-okernel/linux-okernel
+- Userspace components and supporting material:
+  https://github.com/linux-okernel/linux-okernel-components
+
+Similar to the nested-kernel work for BSD by Dautenhan et al[1], the aim
+of the split kernel (okernel) is to introduce a level of intra-kernel
+protection into the kernel so that, amongst other things, we can offer
+lifetime guarantees over kernel code and data integrity.  Unlike the BSD-
+based nested kernel work, we are focused on the Linux kernel (not BSD) and
+do make use of HW virtualization features such as Extended Page Tables
 (EPT) or equivalent to provide protection from malicious kernel
 changes. (Our initial prototype is based on Intel x86, but the
 intention is to be architecture neutral so we can apply it to other
 architectures, including AMD and ARM.)

-The split-kernel provides a (protected) virtualized view of the kernel
+The split kernel provides a (protected) virtualized view of the kernel
 for processes entering the kernel through exceptions, syscalls and
 interrupts. Though we make use of hardware features designed to
 support virtualization, we do not virtualize at the full virtual
@ -62,25 +68,52 @@ to the NR-mode context.
 If a process in NR-mode attempts to change the kernel memory in
 conflict with permissions in the lower-level page tables, a VMEXIT (in
 the current prototype which uses Intel VMX) is triggered. R-mode is
-then entered where will handle the permission violation.
+then entered where the permission violation can be handled.
+
+# Integration with LinuxKit
+
+Custom Linux distributions utilizing the split kernel can be readily built
+using LinuxKit by simply specifying an okernel Docker image in the `kernel`
+section of the OS image YAML specification. See the sample YAML files provided
+in [examples](https://github.com/linuxkit/linuxkit/tree/master/projects/okernel/examples).
+
+## Building the split kernel image for LinuxKit
+
+ - `make` will build and package the latest version of the split kernel, by
+   pulling sources from the top-of-tree of the okernel project GitHub
+   (https://github.com/linux-okernel/linux-okernel).
+ - Additionally, a specific version of the kernel can be built
+   by setting the 'KERNEL' environment variable to the appropriate
+   value, e.g.: `make KERNEL=ok-4.11-rc2`. The value MUST correspond
+   to a legitimate okernel tag present in the project GitHub
+   (https://github.com/linux-okernel/linux-okernel/tags) beginning
+   with __"ok-"__.
+   `make KERNEL=latest` will build the top-of-tree release, equivalent to `make`.
+
+`make kvmod` or `make KERNEL=NNNNNNNN kvmod` where "NNNNNNNN" is the release
+string corresponding to a kernel version, will build the kernel
+vulnerability emulation kernel module for that kernel, useful for testing.
+

 # Limitations and Caveats

 The current implementation does not have any protection of the kernel
-in place yet. It is a demonstration that you can create processes run
-them in NR-mode using EPTs with a shared kernel. As a further
-demonstrations of the concept, it implements protected memory pages,
+in place yet. It is a demonstration that you can create processes and
+run them in NR-mode using EPTs with a shared kernel. As a further
+demonstration of the concept, it implements protected memory pages,
 whereby a process may request a protected memory page which will not
 be mapped into the EPTs for other processes.

+## Roadmap
+
 The next step, and the subject of our ongoing research is to design
 the memory protection architecture for the kernel. Examples of the
 things that we are considering protecting from root mode processes
 are:
- - Protection of the page tables (no NR mode process can modify an
-   page table) 
- - Protection of kernel executable code RX only
- - Protection of kernel data structures RO
+ - Protection of the page tables (no NR mode process can modify a
+   page table)
+ - Protection of kernel executable code (RX only)
+ - Protection of kernel data structures (RO)

 # References

@ -92,5 +125,4 @@ Programming Languages and Operating Systems, March 2015.
 - [2] Dune: Safe user-level access to privileged CPU features, Adam
 Belay, Andrea Bittau, Ali Mashtizadeh, David Terei, David Mazières,
 and Christos Kozyrakis, OSDI '12, Proceedings of the 10th USENIX
-Symposium on Operating Systems Design and Implementation, October
-2012.
+Symposium on Operating Systems Design and Implementation, October 2012.
--- a/projects/okernel/examples/okernel_simple.yaml
+++ b/projects/okernel/examples/okernel_simple.yaml
@ -0,0 +1,49 @@
+kernel:
+  image: "linuxkit/okernel:latest"
+  cmdline: "console=ttyS0 console=tty0 page_poison=1"
+init:
+  - linuxkit/init:63eed9ca7a09d2ce4c0c5e7238ac005fa44f564b
+  - linuxkit/runc:b0fb122e10dbb7e4e45115177a61a3f8d68c19a9
+  - linuxkit/containerd:18eaf72f3f4f9a9f29ca1951f66df701f873060b
+  - linuxkit/ca-certificates:eabc5a6e59f05aa91529d80e9a595b85b046f935
+onboot:
+  - name: sysctl
+    image: "linuxkit/sysctl:2cf2f9d5b4d314ba1bfc22b2fe931924af666d8c"
+    net: host
+    pid: host
+    ipc: host
+    capabilities:
+     - CAP_SYS_ADMIN
+services:
+  - name: rngd
+    image: "linuxkit/rngd:3dad6dd43270fa632ac031e99d1947f20b22eec9"
+    capabilities:
+     - CAP_SYS_ADMIN
+    oomScoreAdj: -800
+  - name: dhcpcd
+    image: "linuxkit/dhcpcd:48e249ebef6a521eed886b3bce032db69fbb4afa"
+    binds:
+     - /var:/var
+     - /tmp:/etc
+    capabilities:
+     - CAP_NET_ADMIN
+     - CAP_NET_BIND_SERVICE
+     - CAP_NET_RAW
+    net: host
+    oomScoreAdj: -800
+  - name: sshd
+    image: "linuxkit/sshd:e108d208adf692c8a0954f602743e0eec445364e"
+    capabilities:
+     - all
+    net: host
+    pid: host
+    binds:
+     - /root/.ssh:/root/.ssh
+     - /etc/resolv.conf:/etc/resolv.conf
+files:
+  - path: root/.ssh/authorized_keys
+    contents: '#your ssh key here'
+outputs:
+  - format: kernel+initrd
+  - format: iso-bios
+  - format: iso-efi
--- a/projects/okernel/kernel_config.okernel
+++ b/projects/okernel/kernel_config.okernel