diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/Changes | 17 | ||||
| -rw-r--r-- | Documentation/kbuild/kbuild.txt | 5 | ||||
| -rw-r--r-- | Documentation/module-signing.txt | 56 | ||||
| -rw-r--r-- | Documentation/security/Smack.txt | 27 | ||||
| -rw-r--r-- | Documentation/security/Yama.txt | 10 |
5 files changed, 95 insertions, 20 deletions
diff --git a/Documentation/Changes b/Documentation/Changes index 646cdaa6e9d1..6d8863004858 100644 --- a/Documentation/Changes +++ b/Documentation/Changes @@ -43,6 +43,7 @@ o udev 081 # udevd --version o grub 0.93 # grub --version || grub-install --version o mcelog 0.6 # mcelog --version o iptables 1.4.2 # iptables -V +o openssl & libcrypto 1.0.1k # openssl version Kernel compilation @@ -79,6 +80,17 @@ BC You will need bc to build kernels 3.10 and higher +OpenSSL +------- + +Module signing and external certificate handling use the OpenSSL program and +crypto library to do key creation and signature generation. + +You will need openssl to build kernels 3.7 and higher if module signing is +enabled. You will also need openssl development packages to build kernels 4.3 +and higher. + + System utilities ================ @@ -295,6 +307,10 @@ Binutils -------- o <ftp://ftp.kernel.org/pub/linux/devel/binutils/> +OpenSSL +------- +o <https://www.openssl.org/> + System utilities **************** @@ -392,4 +408,3 @@ o <http://oprofile.sf.net/download/> NFS-Utils --------- o <http://nfs.sourceforge.net/> - diff --git a/Documentation/kbuild/kbuild.txt b/Documentation/kbuild/kbuild.txt index 6466704d47b5..0ff6a466a05b 100644 --- a/Documentation/kbuild/kbuild.txt +++ b/Documentation/kbuild/kbuild.txt @@ -174,6 +174,11 @@ The output directory is often set using "O=..." on the commandline. The value can be overridden in which case the default value is ignored. +KBUILD_SIGN_PIN +-------------------------------------------------- +This variable allows a passphrase or PIN to be passed to the sign-file +utility when signing kernel modules, if the private key requires such. + KBUILD_MODPOST_WARN -------------------------------------------------- KBUILD_MODPOST_WARN can be set to avoid errors in case of undefined diff --git a/Documentation/module-signing.txt b/Documentation/module-signing.txt index c72702ec1ded..a78bf1ffa68c 100644 --- a/Documentation/module-signing.txt +++ b/Documentation/module-signing.txt @@ -89,6 +89,32 @@ This has a number of options available: their signatures checked without causing a dependency loop. + (4) "File name or PKCS#11 URI of module signing key" (CONFIG_MODULE_SIG_KEY) + + Setting this option to something other than its default of + "certs/signing_key.pem" will disable the autogeneration of signing keys + and allow the kernel modules to be signed with a key of your choosing. + The string provided should identify a file containing both a private key + and its corresponding X.509 certificate in PEM form, or — on systems where + the OpenSSL ENGINE_pkcs11 is functional — a PKCS#11 URI as defined by + RFC7512. In the latter case, the PKCS#11 URI should reference both a + certificate and a private key. + + If the PEM file containing the private key is encrypted, or if the + PKCS#11 token requries a PIN, this can be provided at build time by + means of the KBUILD_SIGN_PIN variable. + + + (5) "Additional X.509 keys for default system keyring" (CONFIG_SYSTEM_TRUSTED_KEYS) + + This option can be set to the filename of a PEM-encoded file containing + additional certificates which will be included in the system keyring by + default. + +Note that enabling module signing adds a dependency on the OpenSSL devel +packages to the kernel build processes for the tool that does the signing. + + ======================= GENERATING SIGNING KEYS ======================= @@ -100,16 +126,16 @@ it can be deleted or stored securely. The public key gets built into the kernel so that it can be used to check the signatures as the modules are loaded. -Under normal conditions, the kernel build will automatically generate a new -keypair using openssl if one does not exist in the files: +Under normal conditions, when CONFIG_MODULE_SIG_KEY is unchanged from its +default, the kernel build will automatically generate a new keypair using +openssl if one does not exist in the file: - signing_key.priv - signing_key.x509 + certs/signing_key.pem during the building of vmlinux (the public part of the key needs to be built into vmlinux) using parameters in the: - x509.genkey + certs/x509.genkey file (which is also generated if it does not already exist). @@ -135,8 +161,12 @@ kernel sources tree and the openssl command. The following is an example to generate the public/private key files: openssl req -new -nodes -utf8 -sha256 -days 36500 -batch -x509 \ - -config x509.genkey -outform DER -out signing_key.x509 \ - -keyout signing_key.priv + -config x509.genkey -outform PEM -out kernel_key.pem \ + -keyout kernel_key.pem + +The full pathname for the resulting kernel_key.pem file can then be specified +in the CONFIG_MODULE_SIG_KEY option, and the certificate and key therein will +be used instead of an autogenerated keypair. ========================= @@ -152,10 +182,9 @@ in a keyring called ".system_keyring" that can be seen by: 302d2d52 I------ 1 perm 1f010000 0 0 asymmetri Fedora kernel signing key: d69a84e6bce3d216b979e9505b3e3ef9a7118079: X509.RSA a7118079 [] ... -Beyond the public key generated specifically for module signing, any file -placed in the kernel source root directory or the kernel build root directory -whose name is suffixed with ".x509" will be assumed to be an X.509 public key -and will be added to the keyring. +Beyond the public key generated specifically for module signing, additional +trusted certificates can be provided in a PEM-encoded file referenced by the +CONFIG_SYSTEM_TRUSTED_KEYS configuration option. Further, the architecture code may take public keys from a hardware store and add those in also (e.g. from the UEFI key database). @@ -181,7 +210,7 @@ To manually sign a module, use the scripts/sign-file tool available in the Linux kernel source tree. The script requires 4 arguments: 1. The hash algorithm (e.g., sha256) - 2. The private key filename + 2. The private key filename or PKCS#11 URI 3. The public key filename 4. The kernel module to be signed @@ -194,6 +223,9 @@ The hash algorithm used does not have to match the one configured, but if it doesn't, you should make sure that hash algorithm is either built into the kernel or can be loaded without requiring itself. +If the private key requires a passphrase or PIN, it can be provided in the +$KBUILD_SIGN_PIN environment variable. + ============================ SIGNED MODULES AND STRIPPING diff --git a/Documentation/security/Smack.txt b/Documentation/security/Smack.txt index de5e1aeca7fb..5e6d07fbed07 100644 --- a/Documentation/security/Smack.txt +++ b/Documentation/security/Smack.txt @@ -28,6 +28,10 @@ Smack kernels use the CIPSO IP option. Some network configurations are intolerant of IP options and can impede access to systems that use them as Smack does. +Smack is used in the Tizen operating system. Please +go to http://wiki.tizen.org for information about how +Smack is used in Tizen. + The current git repository for Smack user space is: git://github.com/smack-team/smack.git @@ -108,6 +112,8 @@ in the smackfs filesystem. This pseudo-filesystem is mounted on /sys/fs/smackfs. access + Provided for backward compatibility. The access2 interface + is preferred and should be used instead. This interface reports whether a subject with the specified Smack label has a particular access to an object with a specified Smack label. Write a fixed format access rule to @@ -136,6 +142,8 @@ change-rule those in the fourth string. If there is no such rule it will be created using the access specified in the third and the fourth strings. cipso + Provided for backward compatibility. The cipso2 interface + is preferred and should be used instead. This interface allows a specific CIPSO header to be assigned to a Smack label. The format accepted on write is: "%24s%4d%4d"["%4d"]... @@ -157,7 +165,19 @@ direct doi This contains the CIPSO domain of interpretation used in network packets. +ipv6host + This interface allows specific IPv6 internet addresses to be + treated as single label hosts. Packets are sent to single + label hosts only from processes that have Smack write access + to the host label. All packets received from single label hosts + are given the specified label. The format accepted on write is: + "%h:%h:%h:%h:%h:%h:%h:%h label" or + "%h:%h:%h:%h:%h:%h:%h:%h/%d label". + The "::" address shortcut is not supported. + If label is "-DELETE" a matched entry will be deleted. load + Provided for backward compatibility. The load2 interface + is preferred and should be used instead. This interface allows access control rules in addition to the system defined rules to be specified. The format accepted on write is: @@ -181,6 +201,8 @@ load2 permissions that are not allowed. The string "r-x--" would specify read and execute access. load-self + Provided for backward compatibility. The load-self2 interface + is preferred and should be used instead. This interface allows process specific access rules to be defined. These rules are only consulted if access would otherwise be permitted, and are intended to provide additional @@ -205,6 +227,8 @@ netlabel received from single label hosts are given the specified label. The format accepted on write is: "%d.%d.%d.%d label" or "%d.%d.%d.%d/%d label". + If the label specified is "-CIPSO" the address is treated + as a host that supports CIPSO headers. onlycap This contains labels processes must have for CAP_MAC_ADMIN and CAP_MAC_OVERRIDE to be effective. If this file is empty @@ -232,7 +256,8 @@ unconfined is dangerous and can ruin the proper labeling of your system. It should never be used in production. -You can add access rules in /etc/smack/accesses. They take the form: +If you are using the smackload utility +you can add access rules in /etc/smack/accesses. They take the form: subjectlabel objectlabel access diff --git a/Documentation/security/Yama.txt b/Documentation/security/Yama.txt index 227a63f018a2..d9ee7d7a6c7f 100644 --- a/Documentation/security/Yama.txt +++ b/Documentation/security/Yama.txt @@ -1,9 +1,7 @@ -Yama is a Linux Security Module that collects a number of system-wide DAC -security protections that are not handled by the core kernel itself. To -select it at boot time, specify "security=yama" (though this will disable -any other LSM). - -Yama is controlled through sysctl in /proc/sys/kernel/yama: +Yama is a Linux Security Module that collects system-wide DAC security +protections that are not handled by the core kernel itself. This is +selectable at build-time with CONFIG_SECURITY_YAMA, and can be controlled +at run-time through sysctls in /proc/sys/kernel/yama: - ptrace_scope |