diff options
Diffstat (limited to 'meta-security/meta-integrity/recipes-kernel')
6 files changed, 273 insertions, 0 deletions
diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux-%.bbappend b/meta-security/meta-integrity/recipes-kernel/linux/linux-%.bbappend new file mode 100644 index 000000000..931854ef8 --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux-%.bbappend @@ -0,0 +1,3 @@ +FILESEXTRAPATHS_prepend := "${THISDIR}/linux:" + +SRC_URI += "${@bb.utils.contains('DISTRO_FEATURES', 'ima', ' file://ima.cfg', '', d)}" diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux/0001-ima-fix-ima_inode_post_setattr.patch b/meta-security/meta-integrity/recipes-kernel/linux/linux/0001-ima-fix-ima_inode_post_setattr.patch new file mode 100644 index 000000000..64016dd3e --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux/0001-ima-fix-ima_inode_post_setattr.patch @@ -0,0 +1,51 @@ +From 45ea681ebc0dd44aaec5d3cc4143b9722070d3ac Mon Sep 17 00:00:00 2001 +From: Mimi Zohar <zohar@linux.vnet.ibm.com> +Date: Tue, 8 Mar 2016 16:43:55 -0500 +Subject: [PATCH] ima: fix ima_inode_post_setattr + +Changing file metadata (eg. uid, guid) could result in having to +re-appraise a file's integrity, but does not change the "new file" +status nor the security.ima xattr. The IMA_PERMIT_DIRECTIO and +IMA_DIGSIG_REQUIRED flags are policy rule specific. This patch +only resets these flags, not the IMA_NEW_FILE or IMA_DIGSIG flags. + +With this patch, changing the file timestamp will not remove the +file signature on new files. + +Upstream-Status: Accepted [https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/security/integrity/ima/ima_appraise.c?id=42a4c603198f0d45b7aa936d3ac6ba1b8bd14a1b] + +Reported-by: Dmitry Rozhkov <dmitry.rozhkov@linux.intel.com> +Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> +--- + security/integrity/ima/ima_appraise.c | 2 +- + security/integrity/integrity.h | 1 + + 2 files changed, 2 insertions(+), 1 deletion(-) + +diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c +index 4df493e..a384ba1 100644 +--- a/security/integrity/ima/ima_appraise.c ++++ b/security/integrity/ima/ima_appraise.c +@@ -327,7 +327,7 @@ void ima_inode_post_setattr(struct dentry *dentry) + if (iint) { + iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED | + IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK | +- IMA_ACTION_FLAGS); ++ IMA_ACTION_RULE_FLAGS); + if (must_appraise) + iint->flags |= IMA_APPRAISE; + } +diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h +index 0fc9519..f9decae 100644 +--- a/security/integrity/integrity.h ++++ b/security/integrity/integrity.h +@@ -28,6 +28,7 @@ + + /* iint cache flags */ + #define IMA_ACTION_FLAGS 0xff000000 ++#define IMA_ACTION_RULE_FLAGS 0x06000000 + #define IMA_DIGSIG 0x01000000 + #define IMA_DIGSIG_REQUIRED 0x02000000 + #define IMA_PERMIT_DIRECTIO 0x04000000 +-- +2.5.0 + diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux/0002-ima-add-support-for-creating-files-using-the-mknodat.patch b/meta-security/meta-integrity/recipes-kernel/linux/linux/0002-ima-add-support-for-creating-files-using-the-mknodat.patch new file mode 100644 index 000000000..6ab7ce277 --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux/0002-ima-add-support-for-creating-files-using-the-mknodat.patch @@ -0,0 +1,138 @@ +From baaec960e9e7be0b526eaf831b079ddfe5c15124 Mon Sep 17 00:00:00 2001 +From: Mimi Zohar <zohar@linux.vnet.ibm.com> +Date: Thu, 10 Mar 2016 18:19:20 +0200 +Subject: [PATCH] ima: add support for creating files using the mknodat + syscall + +Commit 3034a14 "ima: pass 'opened' flag to identify newly created files" +stopped identifying empty files as new files. However new empty files +can be created using the mknodat syscall. On systems with IMA-appraisal +enabled, these empty files are not labeled with security.ima extended +attributes properly, preventing them from subsequently being opened in +order to write the file data contents. This patch marks these empty +files, created using mknodat, as new in order to allow the file data +contents to be written. + +Files with security.ima xattrs containing a file signature are considered +"immutable" and can not be modified. The file contents need to be +written, before signing the file. This patch relaxes this requirement +for new files, allowing the file signature to be written before the file +contents. + +Upstream-Status: Accepted [https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/security/integrity/ima/ima_appraise.c?id=05d1a717ec0430c916a749b94eb90ab74bbfa356] + +Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> +--- + fs/namei.c | 2 ++ + include/linux/ima.h | 7 ++++++- + security/integrity/ima/ima_appraise.c | 3 +++ + security/integrity/ima/ima_main.c | 32 +++++++++++++++++++++++++++++++- + 4 files changed, 42 insertions(+), 2 deletions(-) + +diff --git a/fs/namei.c b/fs/namei.c +index ccd7f98..19502da 100644 +--- a/fs/namei.c ++++ b/fs/namei.c +@@ -3526,6 +3526,8 @@ retry: + switch (mode & S_IFMT) { + case 0: case S_IFREG: + error = vfs_create(path.dentry->d_inode,dentry,mode,true); ++ if (!error) ++ ima_post_path_mknod(dentry); + break; + case S_IFCHR: case S_IFBLK: + error = vfs_mknod(path.dentry->d_inode,dentry,mode, +diff --git a/include/linux/ima.h b/include/linux/ima.h +index 120ccc5..7f51971 100644 +--- a/include/linux/ima.h ++++ b/include/linux/ima.h +@@ -20,7 +20,7 @@ extern void ima_file_free(struct file *file); + extern int ima_file_mmap(struct file *file, unsigned long prot); + extern int ima_module_check(struct file *file); + extern int ima_fw_from_file(struct file *file, char *buf, size_t size); +- ++extern void ima_post_path_mknod(struct dentry *dentry); + #else + static inline int ima_bprm_check(struct linux_binprm *bprm) + { +@@ -52,6 +52,11 @@ static inline int ima_fw_from_file(struct file *file, char *buf, size_t size) + return 0; + } + ++static inline void ima_post_path_mknod(struct dentry *dentry) ++{ ++ return; ++} ++ + #endif /* CONFIG_IMA */ + + #ifdef CONFIG_IMA_APPRAISE +diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c +index 4df493e..20806ea 100644 +--- a/security/integrity/ima/ima_appraise.c ++++ b/security/integrity/ima/ima_appraise.c +@@ -274,6 +274,11 @@ out: + xattr_value->type != EVM_IMA_XATTR_DIGSIG)) { + if (!ima_fix_xattr(dentry, iint)) + status = INTEGRITY_PASS; ++ } else if ((inode->i_size == 0) && ++ (iint->flags & IMA_NEW_FILE) && ++ (xattr_value && ++ xattr_value->type == EVM_IMA_XATTR_DIGSIG)) { ++ status = INTEGRITY_PASS; + } + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, filename, + op, cause, rc, 0); +diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c +index eeee00dc..705bf78 100644 +--- a/security/integrity/ima/ima_main.c ++++ b/security/integrity/ima/ima_main.c +@@ -242,7 +242,8 @@ static int process_measurement(struct file *file, int mask, int function, + ima_audit_measurement(iint, pathname); + + out_digsig: +- if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG)) ++ if ((mask & MAY_WRITE) && (iint->flags & IMA_DIGSIG) && ++ !(iint->flags & IMA_NEW_FILE)) + rc = -EACCES; + kfree(xattr_value); + out_free: +@@ -310,6 +311,35 @@ int ima_file_check(struct file *file, int mask, int opened) + EXPORT_SYMBOL_GPL(ima_file_check); + + /** ++ * ima_post_path_mknod - mark as a new inode ++ * @dentry: newly created dentry ++ * ++ * Mark files created via the mknodat syscall as new, so that the ++ * file data can be written later. ++ */ ++void ima_post_path_mknod(struct dentry *dentry) ++{ ++ struct integrity_iint_cache *iint; ++ struct inode *inode; ++ int must_appraise; ++ ++ if (!dentry || !dentry->d_inode) ++ return; ++ ++ inode = dentry->d_inode; ++ if (inode->i_size != 0) ++ return; ++ ++ must_appraise = ima_must_appraise(inode, MAY_ACCESS, FILE_CHECK); ++ if (!must_appraise) ++ return; ++ ++ iint = integrity_inode_get(inode); ++ if (iint) ++ iint->flags |= IMA_NEW_FILE; ++} ++ ++/** + * ima_module_check - based on policy, collect/store/appraise measurement. + * @file: pointer to the file to be measured/appraised + * +-- +2.5.0 + diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux/Revert-ima-limit-file-hash-setting-by-user-to-fix-an.patch b/meta-security/meta-integrity/recipes-kernel/linux/linux/Revert-ima-limit-file-hash-setting-by-user-to-fix-an.patch new file mode 100644 index 000000000..157c007ba --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux/Revert-ima-limit-file-hash-setting-by-user-to-fix-an.patch @@ -0,0 +1,60 @@ +From a34d61850b680c152e1dcc958ee83c3ab3261c3d Mon Sep 17 00:00:00 2001 +From: Patrick Ohly <patrick.ohly@intel.com> +Date: Tue, 15 Nov 2016 10:10:23 +0100 +Subject: [PATCH] Revert "ima: limit file hash setting by user to fix and log + modes" + +This reverts commit c68ed80c97d9720f51ef31fe91560fdd1e121533. + +The original motivation was security hardening ("File hashes are +automatically set and updated and should not be manually set.") + +However, that hardening ignores and breaks some valid use cases: +- File hashes might not be set because the file is currently + outside of the policy and therefore have to be set by the + creator. Examples: + - Booting into an initramfs with an IMA-enabled kernel but + without setting an IMA policy, then installing + the OS onto the target partition by unpacking a rootfs archive + which has the file hashes pre-computed. + - Unpacking a file into a staging area with meta data (like owner) + that leaves the file outside of the current policy, then changing + the meta data such that it becomes part of the current policy. +- "should not be set manually" implies that the creator is aware + of IMA semantic, the current system's configuration, and then + skips setting file hashes in security.ima if (and only if) the + kernel would prevent it. That's not the case for standard, unmodified + tools. Example: unpacking an archive with security.ima xattrs with + bsdtar or GNU tar. + +Upstream-Status: Submitted [https://sourceforge.net/p/linux-ima/mailman/message/35492824/] + +Signed-off-by: Patrick Ohly <patrick.ohly@intel.com> +--- + security/integrity/ima/ima_appraise.c | 8 ++------ + 1 file changed, 2 insertions(+), 6 deletions(-) + +diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c +index 4b9b4a4..b8b2dd9 100644 +--- a/security/integrity/ima/ima_appraise.c ++++ b/security/integrity/ima/ima_appraise.c +@@ -385,14 +385,10 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, + result = ima_protect_xattr(dentry, xattr_name, xattr_value, + xattr_value_len); + if (result == 1) { +- bool digsig; +- + if (!xattr_value_len || (xvalue->type >= IMA_XATTR_LAST)) + return -EINVAL; +- digsig = (xvalue->type == EVM_IMA_XATTR_DIGSIG); +- if (!digsig && (ima_appraise & IMA_APPRAISE_ENFORCE)) +- return -EPERM; +- ima_reset_appraise_flags(d_backing_inode(dentry), digsig); ++ ima_reset_appraise_flags(d_backing_inode(dentry), ++ (xvalue->type == EVM_IMA_XATTR_DIGSIG) ? 1 : 0); + result = 0; + } + return result; +-- +2.1.4 + diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux/ima.cfg b/meta-security/meta-integrity/recipes-kernel/linux/linux/ima.cfg new file mode 100644 index 000000000..b3e47ba37 --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux/ima.cfg @@ -0,0 +1,18 @@ +CONFIG_IMA=y +CONFIG_IMA_MEASURE_PCR_IDX=10 +CONFIG_IMA_NG_TEMPLATE=y +CONFIG_IMA_DEFAULT_TEMPLATE="ima-ng" +CONFIG_IMA_DEFAULT_HASH_SHA1=y +CONFIG_IMA_DEFAULT_HASH="sha1" +CONFIG_IMA_APPRAISE=y +CONFIG_IMA_APPRAISE_BOOTPARAM=y +CONFIG_IMA_TRUSTED_KEYRING=y +CONFIG_SIGNATURE=y +CONFIG_IMA_WRITE_POLICY=y +CONFIG_IMA_READ_POLICY=y +CONFIG_IMA_LOAD_X509=y +CONFIG_IMA_X509_PATH="/etc/keys/x509_ima.der" + +#CONFIG_INTEGRITY_SIGNATURE=y +#CONFIG_INTEGRITY_ASYMMETRIC_KEYS=y +#CONFIG_INTEGRITY_TRUSTED_KEYRING=y diff --git a/meta-security/meta-integrity/recipes-kernel/linux/linux/ima_evm_root_ca.cfg b/meta-security/meta-integrity/recipes-kernel/linux/linux/ima_evm_root_ca.cfg new file mode 100644 index 000000000..9a454257a --- /dev/null +++ b/meta-security/meta-integrity/recipes-kernel/linux/linux/ima_evm_root_ca.cfg @@ -0,0 +1,3 @@ +# CONFIG_IMA_APPRAISE_SIGNED_INIT is not set +CONFIG_EVM_LOAD_X509=y +CONFIG_EVM_X509_PATH="/etc/keys/x509_evm.der" |