2a7dba391e
SELinux would like to implement a new labeling behavior of newly created inodes. We currently label new inodes based on the parent and the creating process. This new behavior would also take into account the name of the new object when deciding the new label. This is not the (supposed) full path, just the last component of the path. This is very useful because creating /etc/shadow is different than creating /etc/passwd but the kernel hooks are unable to differentiate these operations. We currently require that userspace realize it is doing some difficult operation like that and than userspace jumps through SELinux hoops to get things set up correctly. This patch does not implement new behavior, that is obviously contained in a seperate SELinux patch, but it does pass the needed name down to the correct LSM hook. If no such name exists it is fine to pass NULL. Signed-off-by: Eric Paris <eparis@redhat.com>
79 lines
1.9 KiB
C
79 lines
1.9 KiB
C
/*
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* linux/fs/ext3/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/slab.h>
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#include <linux/string.h>
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#include <linux/fs.h>
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#include <linux/ext3_jbd.h>
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#include <linux/ext3_fs.h>
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#include <linux/security.h>
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#include "xattr.h"
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static size_t
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ext3_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 = XATTR_SECURITY_PREFIX_LEN;
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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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ext3_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 ext3_xattr_get(dentry->d_inode, EXT3_XATTR_INDEX_SECURITY,
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name, buffer, size);
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}
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static int
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ext3_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 ext3_xattr_set(dentry->d_inode, EXT3_XATTR_INDEX_SECURITY,
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name, value, size, flags);
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}
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int
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ext3_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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int err;
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size_t len;
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void *value;
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char *name;
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err = security_inode_init_security(inode, dir, qstr, &name, &value, &len);
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if (err) {
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if (err == -EOPNOTSUPP)
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return 0;
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return err;
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}
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err = ext3_xattr_set_handle(handle, inode, EXT3_XATTR_INDEX_SECURITY,
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name, value, len, 0);
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kfree(name);
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kfree(value);
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return err;
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}
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const struct xattr_handler ext3_xattr_security_handler = {
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.prefix = XATTR_SECURITY_PREFIX,
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.list = ext3_xattr_security_list,
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.get = ext3_xattr_security_get,
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.set = ext3_xattr_security_set,
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};
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