Update README to produce initial evmctl.1 man page

Update README with additional information to produce initial
evmctl.1 man page. Sligtly reformat it for that purpose as well.

Requires asciidoc, xslproc, docbook-xsl packages to build man page.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
This commit is contained in:
Dmitry Kasatkin 2014-09-10 13:08:50 +03:00
parent d5891ad96d
commit 635288f70f
2 changed files with 133 additions and 45 deletions

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@ -1,8 +1,12 @@
SUBDIRS = src SUBDIRS = src
# does work on Ubuntu, but on Fedora different path to XSL stylesheets
#man_MANS = evmctl.1
doc_DATA = examples/ima-genkey-self.sh examples/ima-genkey.sh examples/ima-gen-local-ca.sh doc_DATA = examples/ima-genkey-self.sh examples/ima-genkey.sh examples/ima-gen-local-ca.sh
EXTRA_DIST = autogen.sh $(doc_DATA) EXTRA_DIST = autogen.sh $(doc_DATA)
CLEANFILES = *.html *.1 *.xsl
ACLOCAL_AMFLAGS = -I m4 ACLOCAL_AMFLAGS = -I m4
SRCS = $(HOME)/rpmbuild/SOURCES SRCS = $(HOME)/rpmbuild/SOURCES
@ -20,4 +24,18 @@ rpm: $(tarname)
cp $(tarname) $(SRCS)/ cp $(tarname) $(SRCS)/
rpmbuild -ba --nodeps $(SPEC) rpmbuild -ba --nodeps $(SPEC)
# requires asciidoc, xslproc, docbook-xsl
MANPAGE_DOCBOOK_XSL = /usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl
evmctl.1.html: README
@asciidoc -o $@ $<
evmctl.1.xsl: README
@asciidoc -d manpage -b docbook -o $@ $<
evmctl.1: evmctl.1.xsl
@xsltproc --nonet -o $@ $(MANPAGE_DOCBOOK_XSL) $<
doc: evmctl.1.html evmctl.1
.PHONY: $(tarname) .PHONY: $(tarname)

160
README
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@ -1,12 +1,61 @@
ima-evm-utils - IMA/EVM signing utility EVMCTL(1)
========================================= =========
Contents: NAME
----
1. Key and signature formats evmctl - IMA/EVM signing utility
2. Key generation
3. Initialization
4. Signing SYNOPSIS
--------
evmctl [options] <command> [OPTIONS]
DESCRIPTION
-----------
The evmctl utility can be used for producing and verifying digital signatures,
which are used by Linux kernel integrity subsystem (IMA/EVM). It can be also
used to import keys into the kernel keyring.
COMMANDS
--------
help <command>
import [--rsa] pubkey keyring
sign [-r] [--imahash | --imasig ] [--key key] [--pass password] file
verify file
ima_sign [--sigfile] [--key key] [--pass password] file
ima_verify file
ima_hash file
ima_measurement file
ima_fix [-t fdsxm] path
sign_hash [--key key] [--pass password]
hmac [--imahash | --imasig ] file
OPTIONS
-------
-a, --hashalgo sha1 (default), sha224, sha256, sha384, sha512
-s, --imasig also make IMA signature
-d, --imahash also make IMA hash
-f, --sigfile store IMA signature in .sig file instead of xattr
-1, --rsa signing key is in RSA DER format (signing v1)
-k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)
-p, --pass password for encrypted signing key
-u, --uuid use file system UUID in HMAC calculation (EVM v2)
-t, --type file types to fix 'fdsxm' (f: file, d: directory, s: block/char/symlink)
x - skip fixing if both ima and evm xattrs exist (use with caution)
m - stay on the same filesystem (like 'find -xdev')
-n print result to stdout instead of setting xattr
-r, --recursive recurse into directories (sign)
--m32 force signature for 32 bit target system
--m64 force signature for 32 bit target system
-v increase verbosity level
-h, --help display this help and exit
Key and signature formats Key and signature formats
@ -26,24 +75,24 @@ Use '--rsa' or '-1' parameter to use old signature format and API.
Key generation Key generation
-------------- --------------
Generate private key in plain text format Generate private key in plain text format:
$ openssl genrsa -out privkey_evm.pem 1024 openssl genrsa -out privkey_evm.pem 1024
Generate encrypted private key Generate encrypted private key:
$ openssl genrsa -des3 -out privkey_evm.pem 1024 openssl genrsa -des3 -out privkey_evm.pem 1024
Make encrypted private key from unencrypted Make encrypted private key from unencrypted:
$ openssl rsa -in /etc/keys/privkey_evm.pem -out privkey_evm_enc.pem -des3 openssl rsa -in /etc/keys/privkey_evm.pem -out privkey_evm_enc.pem -des3
Generate self-signed X509 certificate and private key for using kernel asymmetric Generate self-signed X509 certificate and private key for using kernel
keys support asymmetric keys support:
$ openssl req -new -nodes -utf8 -sha1 -days 36500 -batch \ openssl req -new -nodes -utf8 -sha1 -days 36500 -batch \
-x509 -config x509_evm.genkey \ -x509 -config x509_evm.genkey \
-outform DER -out x509_evm.der -keyout privkey_evm.pem -outform DER -out x509_evm.der -keyout privkey_evm.pem
Configuration file x509_evm.genkey: Configuration file x509_evm.genkey:
@ -68,28 +117,28 @@ Configuration file x509_evm.genkey:
# EOF # EOF
Get public key Get public key:
$ openssl rsa -pubout -in privkey_evm.pem -out pubkey_evm.pem openssl rsa -pubout -in privkey_evm.pem -out pubkey_evm.pem
Copy keys to /etc/keys Copy keys to /etc/keys:
$ cp pubkey_evm.pem /etc/keys cp pubkey_evm.pem /etc/keys
$ scp pubkey_evm.pem target:/etc/keys scp pubkey_evm.pem target:/etc/keys
or or
$ cp x509_evm.pem /etc/keys cp x509_evm.pem /etc/keys
$ scp x509_evm.pem target:/etc/keys scp x509_evm.pem target:/etc/keys
Generation of EVM keys Generate EVM keys:
$ # create and save the kernel master key (user type) # create and save the kernel master key (user type)
$ keyctl add user kmk "`dd if=/dev/urandom bs=1 count=32 2>/dev/null`" @u keyctl add user kmk "`dd if=/dev/urandom bs=1 count=32 2>/dev/null`" @u
$ keyctl pipe `keyctl search @u user kmk` > /etc/keys/kmk keyctl pipe `keyctl search @u user kmk` > /etc/keys/kmk
$ # create the EVM encrypted key # create the EVM encrypted key
$ keyctl add encrypted evm-key "new user:kmk 32" @u keyctl add encrypted evm-key "new user:kmk 32" @u
$ keyctl pipe `keyctl search @u encrypted evm-key` >/etc/keys/evm-key keyctl pipe `keyctl search @u encrypted evm-key` >/etc/keys/evm-key
Initialization Initialization
@ -117,10 +166,10 @@ Here is an example script /etc/initramfs-tools/scripts/local-top/ima.sh
echo "1" > /sys/kernel/security/evm echo "1" > /sys/kernel/security/evm
Import X509 certificate into the kernel keyring (since kernel 3.9?) Import X509 certificate into the kernel keyring (since kernel 3.9?):
$ evmctl import /etc/keys/x509_evm.der `keyctl search @u keyring _ima` evmctl import /etc/keys/x509_evm.der `keyctl search @u keyring _ima`
$ evmctl import /etc/keys/x509_evm.der `keyctl search @u keyring _evm` evmctl import /etc/keys/x509_evm.der `keyctl search @u keyring _evm`
Signing Signing
@ -133,23 +182,44 @@ Default X509 certificate: /etc/keys/x509_evm.der
Signing for using old RSA format is done using '-1' or '--rsa' parameter. Signing for using old RSA format is done using '-1' or '--rsa' parameter.
Signing for using old EVM HMAC format is done using '-u-' or '--uuid=-' parameter. Signing for using old EVM HMAC format is done using '-u-' or '--uuid=-' parameter.
Sign file with EVM signature and use hash value for IMA - common case Sign file with EVM signature and use hash value for IMA - common case:
$ evmctl sign [-u] [-1] --imahash test.txt evmctl sign [-u] [-1] --imahash test.txt
Sign file with both IMA and EVM signatures - for immutable files Sign file with both IMA and EVM signatures - for immutable files:
$ evmctl sign [-u] [-1] --imasig test.txt evmctl sign [-u] [-1] --imasig test.txt:
Sign file with IMA signature - for immutable files Sign file with IMA signature - for immutable files:
$ evmctl ima_sign [-1] test.txt evmctl ima_sign [-1] test.txt
Label whole filesystem with EVM signatures Label whole filesystem with EVM signatures:
$ find / \( -fstype rootfs -o -fstype ext4 \) -exec evmctl sign [-u] [-1] --imahash '{}' \; find / \( -fstype rootfs -o -fstype ext4 \) -exec evmctl sign [-u] [-1] --imahash '{}' \;
Label filesystem in fix mode - kernel sets correct values to IMA and EVM xattrs Label filesystem in fix mode - kernel sets correct values to IMA and EVM xattrs:
$ find / \( -fstype rootfs -o -fstype ext4 \) -exec sh -c "< '{}'" \; find / \( -fstype rootfs -o -fstype ext4 \) -exec sh -c "< '{}'" \;
AUTHOR
------
Written by Dmitry Kasatkin, <dmitry.kasatkin at gmail.com>
RESOURCES
---------
http://sourceforge.net/p/linux-ima/wiki/Home
http://sourceforge.net/p/linux-ima/ima-evm-utils
COPYING
-------
Copyright \(C) 2012 - 2014 Dmitry Kasatkin. Free use of this software is granted under
the terms of the GNU Public License (GPL).