9d8f13ba3f
This patch changes the security_inode_init_security API by adding a filesystem specific callback to write security extended attributes. This change is in preparation for supporting the initialization of multiple LSM xattrs and the EVM xattr. Initially the callback function walks an array of xattrs, writing each xattr separately, but could be optimized to write multiple xattrs at once. For existing security_inode_init_security() calls, which have not yet been converted to use the new callback function, such as those in reiserfs and ocfs2, this patch defines security_old_inode_init_security(). Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
83 lines
2.1 KiB
C
83 lines
2.1 KiB
C
/*
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* linux/fs/ext4/xattr_security.c
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* Handler for storing security labels as extended attributes.
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*/
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#include <linux/module.h>
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#include <linux/string.h>
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#include <linux/fs.h>
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#include <linux/security.h>
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#include <linux/slab.h>
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#include "ext4_jbd2.h"
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#include "ext4.h"
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#include "xattr.h"
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static size_t
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ext4_xattr_security_list(struct dentry *dentry, char *list, size_t list_size,
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const char *name, size_t name_len, int type)
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{
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const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
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const size_t total_len = prefix_len + name_len + 1;
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if (list && total_len <= list_size) {
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memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
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memcpy(list+prefix_len, name, name_len);
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list[prefix_len + name_len] = '\0';
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}
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return total_len;
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}
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static int
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ext4_xattr_security_get(struct dentry *dentry, const char *name,
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void *buffer, size_t size, int type)
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{
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if (strcmp(name, "") == 0)
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return -EINVAL;
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return ext4_xattr_get(dentry->d_inode, EXT4_XATTR_INDEX_SECURITY,
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name, buffer, size);
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}
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static int
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ext4_xattr_security_set(struct dentry *dentry, const char *name,
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const void *value, size_t size, int flags, int type)
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{
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if (strcmp(name, "") == 0)
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return -EINVAL;
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return ext4_xattr_set(dentry->d_inode, EXT4_XATTR_INDEX_SECURITY,
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name, value, size, flags);
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}
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int ext4_initxattrs(struct inode *inode, const struct xattr *xattr_array,
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void *fs_info)
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{
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const struct xattr *xattr;
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handle_t *handle = fs_info;
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int err = 0;
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for (xattr = xattr_array; xattr->name != NULL; xattr++) {
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err = ext4_xattr_set_handle(handle, inode,
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EXT4_XATTR_INDEX_SECURITY,
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xattr->name, xattr->value,
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xattr->value_len, 0);
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if (err < 0)
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break;
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}
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return err;
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}
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int
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ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir,
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const struct qstr *qstr)
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{
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return security_inode_init_security(inode, dir, qstr,
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&ext4_initxattrs, handle);
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}
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const struct xattr_handler ext4_xattr_security_handler = {
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.prefix = XATTR_SECURITY_PREFIX,
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.list = ext4_xattr_security_list,
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.get = ext4_xattr_security_get,
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.set = ext4_xattr_security_set,
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};
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