| /* |
| * Simplified MAC Kernel (smack) security module |
| * |
| * This file contains the smack hook function implementations. |
| * |
| * Author: |
| * Casey Schaufler <casey@schaufler-ca.com> |
| * |
| * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2, |
| * as published by the Free Software Foundation. |
| */ |
| |
| #include <linux/xattr.h> |
| #include <linux/pagemap.h> |
| #include <linux/mount.h> |
| #include <linux/stat.h> |
| #include <linux/ext2_fs.h> |
| #include <linux/kd.h> |
| #include <asm/ioctls.h> |
| #include <linux/tcp.h> |
| #include <linux/udp.h> |
| #include <linux/mutex.h> |
| #include <linux/pipe_fs_i.h> |
| #include <net/netlabel.h> |
| #include <net/cipso_ipv4.h> |
| #include <linux/audit.h> |
| |
| #include "smack.h" |
| |
| #define task_security(task) (task_cred_xxx((task), security)) |
| |
| /* |
| * I hope these are the hokeyist lines of code in the module. Casey. |
| */ |
| #define DEVPTS_SUPER_MAGIC 0x1cd1 |
| #define SOCKFS_MAGIC 0x534F434B |
| #define TMPFS_MAGIC 0x01021994 |
| |
| /** |
| * smk_fetch - Fetch the smack label from a file. |
| * @ip: a pointer to the inode |
| * @dp: a pointer to the dentry |
| * |
| * Returns a pointer to the master list entry for the Smack label |
| * or NULL if there was no label to fetch. |
| */ |
| static char *smk_fetch(struct inode *ip, struct dentry *dp) |
| { |
| int rc; |
| char in[SMK_LABELLEN]; |
| |
| if (ip->i_op->getxattr == NULL) |
| return NULL; |
| |
| rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN); |
| if (rc < 0) |
| return NULL; |
| |
| return smk_import(in, rc); |
| } |
| |
| /** |
| * new_inode_smack - allocate an inode security blob |
| * @smack: a pointer to the Smack label to use in the blob |
| * |
| * Returns the new blob or NULL if there's no memory available |
| */ |
| struct inode_smack *new_inode_smack(char *smack) |
| { |
| struct inode_smack *isp; |
| |
| isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL); |
| if (isp == NULL) |
| return NULL; |
| |
| isp->smk_inode = smack; |
| isp->smk_flags = 0; |
| mutex_init(&isp->smk_lock); |
| |
| return isp; |
| } |
| |
| /* |
| * LSM hooks. |
| * We he, that is fun! |
| */ |
| |
| /** |
| * smack_ptrace_may_access - Smack approval on PTRACE_ATTACH |
| * @ctp: child task pointer |
| * |
| * Returns 0 if access is OK, an error code otherwise |
| * |
| * Do the capability checks, and require read and write. |
| */ |
| static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode) |
| { |
| int rc; |
| |
| rc = cap_ptrace_may_access(ctp, mode); |
| if (rc != 0) |
| return rc; |
| |
| rc = smk_access(current_security(), task_security(ctp), MAY_READWRITE); |
| if (rc != 0 && capable(CAP_MAC_OVERRIDE)) |
| return 0; |
| return rc; |
| } |
| |
| /** |
| * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME |
| * @ptp: parent task pointer |
| * |
| * Returns 0 if access is OK, an error code otherwise |
| * |
| * Do the capability checks, and require read and write. |
| */ |
| static int smack_ptrace_traceme(struct task_struct *ptp) |
| { |
| int rc; |
| |
| rc = cap_ptrace_traceme(ptp); |
| if (rc != 0) |
| return rc; |
| |
| rc = smk_access(task_security(ptp), current_security(), MAY_READWRITE); |
| if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE)) |
| return 0; |
| return rc; |
| } |
| |
| /** |
| * smack_syslog - Smack approval on syslog |
| * @type: message type |
| * |
| * Require that the task has the floor label |
| * |
| * Returns 0 on success, error code otherwise. |
| */ |
| static int smack_syslog(int type) |
| { |
| int rc; |
| char *sp = current_security(); |
| |
| rc = cap_syslog(type); |
| if (rc != 0) |
| return rc; |
| |
| if (capable(CAP_MAC_OVERRIDE)) |
| return 0; |
| |
| if (sp != smack_known_floor.smk_known) |
| rc = -EACCES; |
| |
| return rc; |
| } |
| |
| |
| /* |
| * Superblock Hooks. |
| */ |
| |
| /** |
| * smack_sb_alloc_security - allocate a superblock blob |
| * @sb: the superblock getting the blob |
| * |
| * Returns 0 on success or -ENOMEM on error. |
| */ |
| static int smack_sb_alloc_security(struct super_block *sb) |
| { |
| struct superblock_smack *sbsp; |
| |
| sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL); |
| |
| if (sbsp == NULL) |
| return -ENOMEM; |
| |
| sbsp->smk_root = smack_known_floor.smk_known; |
| sbsp->smk_default = smack_known_floor.smk_known; |
| sbsp->smk_floor = smack_known_floor.smk_known; |
| sbsp->smk_hat = smack_known_hat.smk_known; |
| sbsp->smk_initialized = 0; |
| spin_lock_init(&sbsp->smk_sblock); |
| |
| sb->s_security = sbsp; |
| |
| return 0; |
| } |
| |
| /** |
| * smack_sb_free_security - free a superblock blob |
| * @sb: the superblock getting the blob |
| * |
| */ |
| static void smack_sb_free_security(struct super_block *sb) |
| { |
| kfree(sb->s_security); |
| sb->s_security = NULL; |
| } |
| |
| /** |
| * smack_sb_copy_data - copy mount options data for processing |
| * @type: file system type |
| * @orig: where to start |
| * @smackopts |
| * |
| * Returns 0 on success or -ENOMEM on error. |
| * |
| * Copy the Smack specific mount options out of the mount |
| * options list. |
| */ |
| static int smack_sb_copy_data(char *orig, char *smackopts) |
| { |
| char *cp, *commap, *otheropts, *dp; |
| |
| otheropts = (char *)get_zeroed_page(GFP_KERNEL); |
| if (otheropts == NULL) |
| return -ENOMEM; |
| |
| for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) { |
| if (strstr(cp, SMK_FSDEFAULT) == cp) |
| dp = smackopts; |
| else if (strstr(cp, SMK_FSFLOOR) == cp) |
| dp = smackopts; |
| else if (strstr(cp, SMK_FSHAT) == cp) |
| dp = smackopts; |
| else if (strstr(cp, SMK_FSROOT) == cp) |
| dp = smackopts; |
| else |
| dp = otheropts; |
| |
| commap = strchr(cp, ','); |
| if (commap != NULL) |
| *commap = '\0'; |
| |
| if (*dp != '\0') |
| strcat(dp, ","); |
| strcat(dp, cp); |
| } |
| |
| strcpy(orig, otheropts); |
| free_page((unsigned long)otheropts); |
| |
| return 0; |
| } |
| |
| /** |
| * smack_sb_kern_mount - Smack specific mount processing |
| * @sb: the file system superblock |
| * @flags: the mount flags |
| * @data: the smack mount options |
| * |
| * Returns 0 on success, an error code on failure |
| */ |
| static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) |
| { |
| struct dentry *root = sb->s_root; |
| struct inode *inode = root->d_inode; |
| struct superblock_smack *sp = sb->s_security; |
| struct inode_smack *isp; |
| char *op; |
| char *commap; |
| char *nsp; |
| |
| spin_lock(&sp->smk_sblock); |
| if (sp->smk_initialized != 0) { |
| spin_unlock(&sp->smk_sblock); |
| return 0; |
| } |
| sp->smk_initialized = 1; |
| spin_unlock(&sp->smk_sblock); |
| |
| for (op = data; op != NULL; op = commap) { |
| commap = strchr(op, ','); |
| if (commap != NULL) |
| *commap++ = '\0'; |
| |
| if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) { |
| op += strlen(SMK_FSHAT); |
| nsp = smk_import(op, 0); |
| if (nsp != NULL) |
| sp->smk_hat = nsp; |
| } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) { |
| op += strlen(SMK_FSFLOOR); |
| nsp = smk_import(op, 0); |
| if (nsp != NULL) |
| sp->smk_floor = nsp; |
| } else if (strncmp(op, SMK_FSDEFAULT, |
| strlen(SMK_FSDEFAULT)) == 0) { |
| op += strlen(SMK_FSDEFAULT); |
| nsp = smk_import(op, 0); |
| if (nsp != NULL) |
| sp->smk_default = nsp; |
| } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) { |
| op += strlen(SMK_FSROOT); |
| nsp = smk_import(op, 0); |
| if (nsp != NULL) |
| sp->smk_root = nsp; |
| } |
| } |
| |
| /* |
| * Initialize the root inode. |
| */ |
| isp = inode->i_security; |
| if (isp == NULL) |
| inode->i_security = new_inode_smack(sp->smk_root); |
| else |
| isp->smk_inode = sp->smk_root; |
| |
| return 0; |
| } |
| |
| /** |
| * smack_sb_statfs - Smack check on statfs |
| * @dentry: identifies the file system in question |
| * |
| * Returns 0 if current can read the floor of the filesystem, |
| * and error code otherwise |
| */ |
| static int smack_sb_statfs(struct dentry *dentry) |
| { |
| struct superblock_smack *sbp = dentry->d_sb->s_security; |
| |
| return smk_curacc(sbp->smk_floor, MAY_READ); |
| } |
| |
| /** |
| * smack_sb_mount - Smack check for mounting |
| * @dev_name: unused |
| * @nd: mount point |
| * @type: unused |
| * @flags: unused |
| * @data: unused |
| * |
| * Returns 0 if current can write the floor of the filesystem |
| * being mounted on, an error code otherwise. |
| */ |
| static int smack_sb_mount(char *dev_name, struct path *path, |
| char *type, unsigned long flags, void *data) |
| { |
| struct superblock_smack *sbp = path->mnt->mnt_sb->s_security; |
| |
| return smk_curacc(sbp->smk_floor, MAY_WRITE); |
| } |
| |
| /** |
| * smack_sb_umount - Smack check for unmounting |
| * @mnt: file system to unmount |
| * @flags: unused |
| * |
| * Returns 0 if current can write the floor of the filesystem |
| * being unmounted, an error code otherwise. |
| */ |
| static int smack_sb_umount(struct vfsmount *mnt, int flags) |
| { |
| struct superblock_smack *sbp; |
| |
| sbp = mnt->mnt_sb->s_security; |
| |
| return smk_curacc(sbp->smk_floor, MAY_WRITE); |
| } |
| |
| /* |
| * Inode hooks |
| */ |
| |
| /** |
| * smack_inode_alloc_security - allocate an inode blob |
| * @inode - the inode in need of a blob |
| * |
| * Returns 0 if it gets a blob, -ENOMEM otherwise |
| */ |
| static int smack_inode_alloc_security(struct inode *inode) |
| { |
| inode->i_security = new_inode_smack(current_security()); |
| if (inode->i_security == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /** |
| * smack_inode_free_security - free an inode blob |
| * @inode - the inode with a blob |
| * |
| * Clears the blob pointer in inode |
| */ |
| static void smack_inode_free_security(struct inode *inode) |
| { |
| kfree(inode->i_security); |
| inode->i_security = NULL; |
| } |
| |
| /** |
| * smack_inode_init_security - copy out the smack from an inode |
| * @inode: the inode |
| * @dir: unused |
| * @name: where to put the attribute name |
| * @value: where to put the attribute value |
| * @len: where to put the length of the attribute |
| * |
| * Returns 0 if it all works out, -ENOMEM if there's no memory |
| */ |
| static int smack_inode_init_security(struct inode *inode, struct inode *dir, |
| char **name, void **value, size_t *len) |
| { |
| char *isp = smk_of_inode(inode); |
| |
| if (name) { |
| *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); |
| if (*name == NULL) |
| return -ENOMEM; |
| } |
| |
| if (value) { |
| *value = kstrdup(isp, GFP_KERNEL); |
| if (*value == NULL) |
| return -ENOMEM; |
| } |
| |
| if (len) |
| *len = strlen(isp) + 1; |
| |
| return 0; |
| } |
| |
| /** |
| * smack_inode_link - Smack check on link |
| * @old_dentry: the existing object |
| * @dir: unused |
| * @new_dentry: the new object |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, |
| struct dentry *new_dentry) |
| { |
| int rc; |
| char *isp; |
| |
| isp = smk_of_inode(old_dentry->d_inode); |
| rc = smk_curacc(isp, MAY_WRITE); |
| |
| if (rc == 0 && new_dentry->d_inode != NULL) { |
| isp = smk_of_inode(new_dentry->d_inode); |
| rc = smk_curacc(isp, MAY_WRITE); |
| } |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_unlink - Smack check on inode deletion |
| * @dir: containing directory object |
| * @dentry: file to unlink |
| * |
| * Returns 0 if current can write the containing directory |
| * and the object, error code otherwise |
| */ |
| static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *ip = dentry->d_inode; |
| int rc; |
| |
| /* |
| * You need write access to the thing you're unlinking |
| */ |
| rc = smk_curacc(smk_of_inode(ip), MAY_WRITE); |
| if (rc == 0) |
| /* |
| * You also need write access to the containing directory |
| */ |
| rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_rmdir - Smack check on directory deletion |
| * @dir: containing directory object |
| * @dentry: directory to unlink |
| * |
| * Returns 0 if current can write the containing directory |
| * and the directory, error code otherwise |
| */ |
| static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| int rc; |
| |
| /* |
| * You need write access to the thing you're removing |
| */ |
| rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); |
| if (rc == 0) |
| /* |
| * You also need write access to the containing directory |
| */ |
| rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_rename - Smack check on rename |
| * @old_inode: the old directory |
| * @old_dentry: unused |
| * @new_inode: the new directory |
| * @new_dentry: unused |
| * |
| * Read and write access is required on both the old and |
| * new directories. |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_rename(struct inode *old_inode, |
| struct dentry *old_dentry, |
| struct inode *new_inode, |
| struct dentry *new_dentry) |
| { |
| int rc; |
| char *isp; |
| |
| isp = smk_of_inode(old_dentry->d_inode); |
| rc = smk_curacc(isp, MAY_READWRITE); |
| |
| if (rc == 0 && new_dentry->d_inode != NULL) { |
| isp = smk_of_inode(new_dentry->d_inode); |
| rc = smk_curacc(isp, MAY_READWRITE); |
| } |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_permission - Smack version of permission() |
| * @inode: the inode in question |
| * @mask: the access requested |
| * @nd: unused |
| * |
| * This is the important Smack hook. |
| * |
| * Returns 0 if access is permitted, -EACCES otherwise |
| */ |
| static int smack_inode_permission(struct inode *inode, int mask) |
| { |
| /* |
| * No permission to check. Existence test. Yup, it's there. |
| */ |
| if (mask == 0) |
| return 0; |
| |
| return smk_curacc(smk_of_inode(inode), mask); |
| } |
| |
| /** |
| * smack_inode_setattr - Smack check for setting attributes |
| * @dentry: the object |
| * @iattr: for the force flag |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) |
| { |
| /* |
| * Need to allow for clearing the setuid bit. |
| */ |
| if (iattr->ia_valid & ATTR_FORCE) |
| return 0; |
| |
| return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); |
| } |
| |
| /** |
| * smack_inode_getattr - Smack check for getting attributes |
| * @mnt: unused |
| * @dentry: the object |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) |
| { |
| return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); |
| } |
| |
| /** |
| * smack_inode_setxattr - Smack check for setting xattrs |
| * @dentry: the object |
| * @name: name of the attribute |
| * @value: unused |
| * @size: unused |
| * @flags: unused |
| * |
| * This protects the Smack attribute explicitly. |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| int rc = 0; |
| |
| if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
| strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || |
| strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { |
| if (!capable(CAP_MAC_ADMIN)) |
| rc = -EPERM; |
| } else |
| rc = cap_inode_setxattr(dentry, name, value, size, flags); |
| |
| if (rc == 0) |
| rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_post_setxattr - Apply the Smack update approved above |
| * @dentry: object |
| * @name: attribute name |
| * @value: attribute value |
| * @size: attribute size |
| * @flags: unused |
| * |
| * Set the pointer in the inode blob to the entry found |
| * in the master label list. |
| */ |
| static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| struct inode_smack *isp; |
| char *nsp; |
| |
| /* |
| * Not SMACK |
| */ |
| if (strcmp(name, XATTR_NAME_SMACK)) |
| return; |
| |
| if (size >= SMK_LABELLEN) |
| return; |
| |
| isp = dentry->d_inode->i_security; |
| |
| /* |
| * No locking is done here. This is a pointer |
| * assignment. |
| */ |
| nsp = smk_import(value, size); |
| if (nsp != NULL) |
| isp->smk_inode = nsp; |
| else |
| isp->smk_inode = smack_known_invalid.smk_known; |
| |
| return; |
| } |
| |
| /* |
| * smack_inode_getxattr - Smack check on getxattr |
| * @dentry: the object |
| * @name: unused |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_getxattr(struct dentry *dentry, const char *name) |
| { |
| return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); |
| } |
| |
| /* |
| * smack_inode_removexattr - Smack check on removexattr |
| * @dentry: the object |
| * @name: name of the attribute |
| * |
| * Removing the Smack attribute requires CAP_MAC_ADMIN |
| * |
| * Returns 0 if access is permitted, an error code otherwise |
| */ |
| static int smack_inode_removexattr(struct dentry *dentry, const char *name) |
| { |
| int rc = 0; |
| |
| if (strcmp(name, XATTR_NAME_SMACK) == 0 || |
| strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || |
| strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { |
| if (!capable(CAP_MAC_ADMIN)) |
| rc = -EPERM; |
| } else |
| rc = cap_inode_removexattr(dentry, name); |
| |
| if (rc == 0) |
| rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_getsecurity - get smack xattrs |
| * @inode: the object |
| * @name: attribute name |
| * @buffer: where to put the result |
| * @size: size of the buffer |
| * @err: unused |
| * |
| * Returns the size of the attribute or an error code |
| */ |
| static int smack_inode_getsecurity(const struct inode *inode, |
| const char *name, void **buffer, |
| bool alloc) |
| { |
| struct socket_smack *ssp; |
| struct socket *sock; |
| struct super_block *sbp; |
| struct inode *ip = (struct inode *)inode; |
| char *isp; |
| int ilen; |
| int rc = 0; |
| |
| if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { |
| isp = smk_of_inode(inode); |
| ilen = strlen(isp) + 1; |
| *buffer = isp; |
| return ilen; |
| } |
| |
| /* |
| * The rest of the Smack xattrs are only on sockets. |
| */ |
| sbp = ip->i_sb; |
| if (sbp->s_magic != SOCKFS_MAGIC) |
| return -EOPNOTSUPP; |
| |
| sock = SOCKET_I(ip); |
| if (sock == NULL || sock->sk == NULL) |
| return -EOPNOTSUPP; |
| |
| ssp = sock->sk->sk_security; |
| |
| if (strcmp(name, XATTR_SMACK_IPIN) == 0) |
| isp = ssp->smk_in; |
| else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) |
| isp = ssp->smk_out; |
| else |
| return -EOPNOTSUPP; |
| |
| ilen = strlen(isp) + 1; |
| if (rc == 0) { |
| *buffer = isp; |
| rc = ilen; |
| } |
| |
| return rc; |
| } |
| |
| |
| /** |
| * smack_inode_listsecurity - list the Smack attributes |
| * @inode: the object |
| * @buffer: where they go |
| * @buffer_size: size of buffer |
| * |
| * Returns 0 on success, -EINVAL otherwise |
| */ |
| static int smack_inode_listsecurity(struct inode *inode, char *buffer, |
| size_t buffer_size) |
| { |
| int len = strlen(XATTR_NAME_SMACK); |
| |
| if (buffer != NULL && len <= buffer_size) { |
| memcpy(buffer, XATTR_NAME_SMACK, len); |
| return len; |
| } |
| return -EINVAL; |
| } |
| |
| /** |
| * smack_inode_getsecid - Extract inode's security id |
| * @inode: inode to extract the info from |
| * @secid: where result will be saved |
| */ |
| static void smack_inode_getsecid(const struct inode *inode, u32 *secid) |
| { |
| struct inode_smack *isp = inode->i_security; |
| |
| *secid = smack_to_secid(isp->smk_inode); |
| } |
| |
| /* |
| * File Hooks |
| */ |
| |
| /** |
| * smack_file_permission - Smack check on file operations |
| * @file: unused |
| * @mask: unused |
| * |
| * Returns 0 |
| * |
| * Should access checks be done on each read or write? |
| * UNICOS and SELinux say yes. |
| * Trusted Solaris, Trusted Irix, and just about everyone else says no. |
| * |
| * I'll say no for now. Smack does not do the frequent |
| * label changing that SELinux does. |
| */ |
| static int smack_file_permission(struct file *file, int mask) |
| { |
| return 0; |
| } |
| |
| /** |
| * smack_file_alloc_security - assign a file security blob |
| * @file: the object |
| * |
| * The security blob for a file is a pointer to the master |
| * label list, so no allocation is done. |
| * |
| * Returns 0 |
| */ |
| static int smack_file_alloc_security(struct file *file) |
| { |
| file->f_security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_file_free_security - clear a file security blob |
| * @file: the object |
| * |
| * The security blob for a file is a pointer to the master |
| * label list, so no memory is freed. |
| */ |
| static void smack_file_free_security(struct file *file) |
| { |
| file->f_security = NULL; |
| } |
| |
| /** |
| * smack_file_ioctl - Smack check on ioctls |
| * @file: the object |
| * @cmd: what to do |
| * @arg: unused |
| * |
| * Relies heavily on the correct use of the ioctl command conventions. |
| * |
| * Returns 0 if allowed, error code otherwise |
| */ |
| static int smack_file_ioctl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| int rc = 0; |
| |
| if (_IOC_DIR(cmd) & _IOC_WRITE) |
| rc = smk_curacc(file->f_security, MAY_WRITE); |
| |
| if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) |
| rc = smk_curacc(file->f_security, MAY_READ); |
| |
| return rc; |
| } |
| |
| /** |
| * smack_file_lock - Smack check on file locking |
| * @file: the object |
| * @cmd unused |
| * |
| * Returns 0 if current has write access, error code otherwise |
| */ |
| static int smack_file_lock(struct file *file, unsigned int cmd) |
| { |
| return smk_curacc(file->f_security, MAY_WRITE); |
| } |
| |
| /** |
| * smack_file_fcntl - Smack check on fcntl |
| * @file: the object |
| * @cmd: what action to check |
| * @arg: unused |
| * |
| * Returns 0 if current has access, error code otherwise |
| */ |
| static int smack_file_fcntl(struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| int rc; |
| |
| switch (cmd) { |
| case F_DUPFD: |
| case F_GETFD: |
| case F_GETFL: |
| case F_GETLK: |
| case F_GETOWN: |
| case F_GETSIG: |
| rc = smk_curacc(file->f_security, MAY_READ); |
| break; |
| case F_SETFD: |
| case F_SETFL: |
| case F_SETLK: |
| case F_SETLKW: |
| case F_SETOWN: |
| case F_SETSIG: |
| rc = smk_curacc(file->f_security, MAY_WRITE); |
| break; |
| default: |
| rc = smk_curacc(file->f_security, MAY_READWRITE); |
| } |
| |
| return rc; |
| } |
| |
| /** |
| * smack_file_set_fowner - set the file security blob value |
| * @file: object in question |
| * |
| * Returns 0 |
| * Further research may be required on this one. |
| */ |
| static int smack_file_set_fowner(struct file *file) |
| { |
| file->f_security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_file_send_sigiotask - Smack on sigio |
| * @tsk: The target task |
| * @fown: the object the signal come from |
| * @signum: unused |
| * |
| * Allow a privileged task to get signals even if it shouldn't |
| * |
| * Returns 0 if a subject with the object's smack could |
| * write to the task, an error code otherwise. |
| */ |
| static int smack_file_send_sigiotask(struct task_struct *tsk, |
| struct fown_struct *fown, int signum) |
| { |
| struct file *file; |
| int rc; |
| |
| /* |
| * struct fown_struct is never outside the context of a struct file |
| */ |
| file = container_of(fown, struct file, f_owner); |
| rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE); |
| if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) |
| return 0; |
| return rc; |
| } |
| |
| /** |
| * smack_file_receive - Smack file receive check |
| * @file: the object |
| * |
| * Returns 0 if current has access, error code otherwise |
| */ |
| static int smack_file_receive(struct file *file) |
| { |
| int may = 0; |
| |
| /* |
| * This code relies on bitmasks. |
| */ |
| if (file->f_mode & FMODE_READ) |
| may = MAY_READ; |
| if (file->f_mode & FMODE_WRITE) |
| may |= MAY_WRITE; |
| |
| return smk_curacc(file->f_security, may); |
| } |
| |
| /* |
| * Task hooks |
| */ |
| |
| /** |
| * smack_cred_free - "free" task-level security credentials |
| * @cred: the credentials in question |
| * |
| * Smack isn't using copies of blobs. Everyone |
| * points to an immutable list. The blobs never go away. |
| * There is no leak here. |
| */ |
| static void smack_cred_free(struct cred *cred) |
| { |
| cred->security = NULL; |
| } |
| |
| /** |
| * smack_cred_prepare - prepare new set of credentials for modification |
| * @new: the new credentials |
| * @old: the original credentials |
| * @gfp: the atomicity of any memory allocations |
| * |
| * Prepare a new set of credentials for modification. |
| */ |
| static int smack_cred_prepare(struct cred *new, const struct cred *old, |
| gfp_t gfp) |
| { |
| new->security = old->security; |
| return 0; |
| } |
| |
| /* |
| * commit new credentials |
| * @new: the new credentials |
| * @old: the original credentials |
| */ |
| static void smack_cred_commit(struct cred *new, const struct cred *old) |
| { |
| } |
| |
| /** |
| * smack_kernel_act_as - Set the subjective context in a set of credentials |
| * @new points to the set of credentials to be modified. |
| * @secid specifies the security ID to be set |
| * |
| * Set the security data for a kernel service. |
| */ |
| static int smack_kernel_act_as(struct cred *new, u32 secid) |
| { |
| char *smack = smack_from_secid(secid); |
| |
| if (smack == NULL) |
| return -EINVAL; |
| |
| new->security = smack; |
| return 0; |
| } |
| |
| /** |
| * smack_kernel_create_files_as - Set the file creation label in a set of creds |
| * @new points to the set of credentials to be modified |
| * @inode points to the inode to use as a reference |
| * |
| * Set the file creation context in a set of credentials to the same |
| * as the objective context of the specified inode |
| */ |
| static int smack_kernel_create_files_as(struct cred *new, |
| struct inode *inode) |
| { |
| struct inode_smack *isp = inode->i_security; |
| |
| new->security = isp->smk_inode; |
| return 0; |
| } |
| |
| /** |
| * smack_task_setpgid - Smack check on setting pgid |
| * @p: the task object |
| * @pgid: unused |
| * |
| * Return 0 if write access is permitted |
| */ |
| static int smack_task_setpgid(struct task_struct *p, pid_t pgid) |
| { |
| return smk_curacc(task_security(p), MAY_WRITE); |
| } |
| |
| /** |
| * smack_task_getpgid - Smack access check for getpgid |
| * @p: the object task |
| * |
| * Returns 0 if current can read the object task, error code otherwise |
| */ |
| static int smack_task_getpgid(struct task_struct *p) |
| { |
| return smk_curacc(task_security(p), MAY_READ); |
| } |
| |
| /** |
| * smack_task_getsid - Smack access check for getsid |
| * @p: the object task |
| * |
| * Returns 0 if current can read the object task, error code otherwise |
| */ |
| static int smack_task_getsid(struct task_struct *p) |
| { |
| return smk_curacc(task_security(p), MAY_READ); |
| } |
| |
| /** |
| * smack_task_getsecid - get the secid of the task |
| * @p: the object task |
| * @secid: where to put the result |
| * |
| * Sets the secid to contain a u32 version of the smack label. |
| */ |
| static void smack_task_getsecid(struct task_struct *p, u32 *secid) |
| { |
| *secid = smack_to_secid(task_security(p)); |
| } |
| |
| /** |
| * smack_task_setnice - Smack check on setting nice |
| * @p: the task object |
| * @nice: unused |
| * |
| * Return 0 if write access is permitted |
| */ |
| static int smack_task_setnice(struct task_struct *p, int nice) |
| { |
| int rc; |
| |
| rc = cap_task_setnice(p, nice); |
| if (rc == 0) |
| rc = smk_curacc(task_security(p), MAY_WRITE); |
| return rc; |
| } |
| |
| /** |
| * smack_task_setioprio - Smack check on setting ioprio |
| * @p: the task object |
| * @ioprio: unused |
| * |
| * Return 0 if write access is permitted |
| */ |
| static int smack_task_setioprio(struct task_struct *p, int ioprio) |
| { |
| int rc; |
| |
| rc = cap_task_setioprio(p, ioprio); |
| if (rc == 0) |
| rc = smk_curacc(task_security(p), MAY_WRITE); |
| return rc; |
| } |
| |
| /** |
| * smack_task_getioprio - Smack check on reading ioprio |
| * @p: the task object |
| * |
| * Return 0 if read access is permitted |
| */ |
| static int smack_task_getioprio(struct task_struct *p) |
| { |
| return smk_curacc(task_security(p), MAY_READ); |
| } |
| |
| /** |
| * smack_task_setscheduler - Smack check on setting scheduler |
| * @p: the task object |
| * @policy: unused |
| * @lp: unused |
| * |
| * Return 0 if read access is permitted |
| */ |
| static int smack_task_setscheduler(struct task_struct *p, int policy, |
| struct sched_param *lp) |
| { |
| int rc; |
| |
| rc = cap_task_setscheduler(p, policy, lp); |
| if (rc == 0) |
| rc = smk_curacc(task_security(p), MAY_WRITE); |
| return rc; |
| } |
| |
| /** |
| * smack_task_getscheduler - Smack check on reading scheduler |
| * @p: the task object |
| * |
| * Return 0 if read access is permitted |
| */ |
| static int smack_task_getscheduler(struct task_struct *p) |
| { |
| return smk_curacc(task_security(p), MAY_READ); |
| } |
| |
| /** |
| * smack_task_movememory - Smack check on moving memory |
| * @p: the task object |
| * |
| * Return 0 if write access is permitted |
| */ |
| static int smack_task_movememory(struct task_struct *p) |
| { |
| return smk_curacc(task_security(p), MAY_WRITE); |
| } |
| |
| /** |
| * smack_task_kill - Smack check on signal delivery |
| * @p: the task object |
| * @info: unused |
| * @sig: unused |
| * @secid: identifies the smack to use in lieu of current's |
| * |
| * Return 0 if write access is permitted |
| * |
| * The secid behavior is an artifact of an SELinux hack |
| * in the USB code. Someday it may go away. |
| */ |
| static int smack_task_kill(struct task_struct *p, struct siginfo *info, |
| int sig, u32 secid) |
| { |
| /* |
| * Sending a signal requires that the sender |
| * can write the receiver. |
| */ |
| if (secid == 0) |
| return smk_curacc(task_security(p), MAY_WRITE); |
| /* |
| * If the secid isn't 0 we're dealing with some USB IO |
| * specific behavior. This is not clean. For one thing |
| * we can't take privilege into account. |
| */ |
| return smk_access(smack_from_secid(secid), task_security(p), MAY_WRITE); |
| } |
| |
| /** |
| * smack_task_wait - Smack access check for waiting |
| * @p: task to wait for |
| * |
| * Returns 0 if current can wait for p, error code otherwise |
| */ |
| static int smack_task_wait(struct task_struct *p) |
| { |
| int rc; |
| |
| rc = smk_access(current_security(), task_security(p), MAY_WRITE); |
| if (rc == 0) |
| return 0; |
| |
| /* |
| * Allow the operation to succeed if either task |
| * has privilege to perform operations that might |
| * account for the smack labels having gotten to |
| * be different in the first place. |
| * |
| * This breaks the strict subject/object access |
| * control ideal, taking the object's privilege |
| * state into account in the decision as well as |
| * the smack value. |
| */ |
| if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE)) |
| return 0; |
| |
| return rc; |
| } |
| |
| /** |
| * smack_task_to_inode - copy task smack into the inode blob |
| * @p: task to copy from |
| * inode: inode to copy to |
| * |
| * Sets the smack pointer in the inode security blob |
| */ |
| static void smack_task_to_inode(struct task_struct *p, struct inode *inode) |
| { |
| struct inode_smack *isp = inode->i_security; |
| isp->smk_inode = task_security(p); |
| } |
| |
| /* |
| * Socket hooks. |
| */ |
| |
| /** |
| * smack_sk_alloc_security - Allocate a socket blob |
| * @sk: the socket |
| * @family: unused |
| * @priority: memory allocation priority |
| * |
| * Assign Smack pointers to current |
| * |
| * Returns 0 on success, -ENOMEM is there's no memory |
| */ |
| static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) |
| { |
| char *csp = current_security(); |
| struct socket_smack *ssp; |
| |
| ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); |
| if (ssp == NULL) |
| return -ENOMEM; |
| |
| ssp->smk_in = csp; |
| ssp->smk_out = csp; |
| ssp->smk_labeled = SMACK_CIPSO_SOCKET; |
| ssp->smk_packet[0] = '\0'; |
| |
| sk->sk_security = ssp; |
| |
| return 0; |
| } |
| |
| /** |
| * smack_sk_free_security - Free a socket blob |
| * @sk: the socket |
| * |
| * Clears the blob pointer |
| */ |
| static void smack_sk_free_security(struct sock *sk) |
| { |
| kfree(sk->sk_security); |
| } |
| |
| /** |
| * smack_set_catset - convert a capset to netlabel mls categories |
| * @catset: the Smack categories |
| * @sap: where to put the netlabel categories |
| * |
| * Allocates and fills attr.mls.cat |
| */ |
| static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap) |
| { |
| unsigned char *cp; |
| unsigned char m; |
| int cat; |
| int rc; |
| int byte; |
| |
| if (!catset) |
| return; |
| |
| sap->flags |= NETLBL_SECATTR_MLS_CAT; |
| sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); |
| sap->attr.mls.cat->startbit = 0; |
| |
| for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++) |
| for (m = 0x80; m != 0; m >>= 1, cat++) { |
| if ((m & *cp) == 0) |
| continue; |
| rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat, |
| cat, GFP_ATOMIC); |
| } |
| } |
| |
| /** |
| * smack_to_secattr - fill a secattr from a smack value |
| * @smack: the smack value |
| * @nlsp: where the result goes |
| * |
| * Casey says that CIPSO is good enough for now. |
| * It can be used to effect. |
| * It can also be abused to effect when necessary. |
| * Appologies to the TSIG group in general and GW in particular. |
| */ |
| static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) |
| { |
| struct smack_cipso cipso; |
| int rc; |
| |
| nlsp->domain = smack; |
| nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; |
| |
| rc = smack_to_cipso(smack, &cipso); |
| if (rc == 0) { |
| nlsp->attr.mls.lvl = cipso.smk_level; |
| smack_set_catset(cipso.smk_catset, nlsp); |
| } else { |
| nlsp->attr.mls.lvl = smack_cipso_direct; |
| smack_set_catset(smack, nlsp); |
| } |
| } |
| |
| /** |
| * smack_netlabel - Set the secattr on a socket |
| * @sk: the socket |
| * @labeled: socket label scheme |
| * |
| * Convert the outbound smack value (smk_out) to a |
| * secattr and attach it to the socket. |
| * |
| * Returns 0 on success or an error code |
| */ |
| static int smack_netlabel(struct sock *sk, int labeled) |
| { |
| struct socket_smack *ssp; |
| struct netlbl_lsm_secattr secattr; |
| int rc = 0; |
| |
| ssp = sk->sk_security; |
| /* |
| * Usually the netlabel code will handle changing the |
| * packet labeling based on the label. |
| * The case of a single label host is different, because |
| * a single label host should never get a labeled packet |
| * even though the label is usually associated with a packet |
| * label. |
| */ |
| local_bh_disable(); |
| bh_lock_sock_nested(sk); |
| |
| if (ssp->smk_out == smack_net_ambient || |
| labeled == SMACK_UNLABELED_SOCKET) |
| netlbl_sock_delattr(sk); |
| else { |
| netlbl_secattr_init(&secattr); |
| smack_to_secattr(ssp->smk_out, &secattr); |
| rc = netlbl_sock_setattr(sk, &secattr); |
| netlbl_secattr_destroy(&secattr); |
| } |
| |
| bh_unlock_sock(sk); |
| local_bh_enable(); |
| /* |
| * Remember the label scheme used so that it is not |
| * necessary to do the netlabel setting if it has not |
| * changed the next time through. |
| * |
| * The -EDESTADDRREQ case is an indication that there's |
| * a single level host involved. |
| */ |
| if (rc == 0) |
| ssp->smk_labeled = labeled; |
| |
| return rc; |
| } |
| |
| /** |
| * smack_inode_setsecurity - set smack xattrs |
| * @inode: the object |
| * @name: attribute name |
| * @value: attribute value |
| * @size: size of the attribute |
| * @flags: unused |
| * |
| * Sets the named attribute in the appropriate blob |
| * |
| * Returns 0 on success, or an error code |
| */ |
| static int smack_inode_setsecurity(struct inode *inode, const char *name, |
| const void *value, size_t size, int flags) |
| { |
| char *sp; |
| struct inode_smack *nsp = inode->i_security; |
| struct socket_smack *ssp; |
| struct socket *sock; |
| int rc = 0; |
| |
| if (value == NULL || size > SMK_LABELLEN) |
| return -EACCES; |
| |
| sp = smk_import(value, size); |
| if (sp == NULL) |
| return -EINVAL; |
| |
| if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { |
| nsp->smk_inode = sp; |
| return 0; |
| } |
| /* |
| * The rest of the Smack xattrs are only on sockets. |
| */ |
| if (inode->i_sb->s_magic != SOCKFS_MAGIC) |
| return -EOPNOTSUPP; |
| |
| sock = SOCKET_I(inode); |
| if (sock == NULL || sock->sk == NULL) |
| return -EOPNOTSUPP; |
| |
| ssp = sock->sk->sk_security; |
| |
| if (strcmp(name, XATTR_SMACK_IPIN) == 0) |
| ssp->smk_in = sp; |
| else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { |
| ssp->smk_out = sp; |
| rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
| if (rc != 0) |
| printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", |
| __func__, -rc); |
| } else |
| return -EOPNOTSUPP; |
| |
| return 0; |
| } |
| |
| /** |
| * smack_socket_post_create - finish socket setup |
| * @sock: the socket |
| * @family: protocol family |
| * @type: unused |
| * @protocol: unused |
| * @kern: unused |
| * |
| * Sets the netlabel information on the socket |
| * |
| * Returns 0 on success, and error code otherwise |
| */ |
| static int smack_socket_post_create(struct socket *sock, int family, |
| int type, int protocol, int kern) |
| { |
| if (family != PF_INET || sock->sk == NULL) |
| return 0; |
| /* |
| * Set the outbound netlbl. |
| */ |
| return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
| } |
| |
| |
| /** |
| * smack_host_label - check host based restrictions |
| * @sip: the object end |
| * |
| * looks for host based access restrictions |
| * |
| * This version will only be appropriate for really small |
| * sets of single label hosts. Because of the masking |
| * it cannot shortcut out on the first match. There are |
| * numerious ways to address the problem, but none of them |
| * have been applied here. |
| * |
| * Returns the label of the far end or NULL if it's not special. |
| */ |
| static char *smack_host_label(struct sockaddr_in *sip) |
| { |
| struct smk_netlbladdr *snp; |
| char *bestlabel = NULL; |
| struct in_addr *siap = &sip->sin_addr; |
| struct in_addr *liap; |
| struct in_addr *miap; |
| struct in_addr bestmask; |
| |
| if (siap->s_addr == 0) |
| return NULL; |
| |
| bestmask.s_addr = 0; |
| |
| for (snp = smack_netlbladdrs; snp != NULL; snp = snp->smk_next) { |
| liap = &snp->smk_host.sin_addr; |
| miap = &snp->smk_mask; |
| /* |
| * If the addresses match after applying the list entry mask |
| * the entry matches the address. If it doesn't move along to |
| * the next entry. |
| */ |
| if ((liap->s_addr & miap->s_addr) != |
| (siap->s_addr & miap->s_addr)) |
| continue; |
| /* |
| * If the list entry mask identifies a single address |
| * it can't get any more specific. |
| */ |
| if (miap->s_addr == 0xffffffff) |
| return snp->smk_label; |
| /* |
| * If the list entry mask is less specific than the best |
| * already found this entry is uninteresting. |
| */ |
| if ((miap->s_addr | bestmask.s_addr) == bestmask.s_addr) |
| continue; |
| /* |
| * This is better than any entry found so far. |
| */ |
| bestmask.s_addr = miap->s_addr; |
| bestlabel = snp->smk_label; |
| } |
| |
| return bestlabel; |
| } |
| |
| /** |
| * smack_socket_connect - connect access check |
| * @sock: the socket |
| * @sap: the other end |
| * @addrlen: size of sap |
| * |
| * Verifies that a connection may be possible |
| * |
| * Returns 0 on success, and error code otherwise |
| */ |
| static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, |
| int addrlen) |
| { |
| struct socket_smack *ssp = sock->sk->sk_security; |
| char *hostsp; |
| int rc; |
| |
| if (sock->sk == NULL || sock->sk->sk_family != PF_INET) |
| return 0; |
| |
| if (addrlen < sizeof(struct sockaddr_in)) |
| return -EINVAL; |
| |
| hostsp = smack_host_label((struct sockaddr_in *)sap); |
| if (hostsp == NULL) { |
| if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) |
| return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
| return 0; |
| } |
| |
| rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); |
| if (rc != 0) |
| return rc; |
| |
| if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) |
| return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); |
| return 0; |
| } |
| |
| /** |
| * smack_flags_to_may - convert S_ to MAY_ values |
| * @flags: the S_ value |
| * |
| * Returns the equivalent MAY_ value |
| */ |
| static int smack_flags_to_may(int flags) |
| { |
| int may = 0; |
| |
| if (flags & S_IRUGO) |
| may |= MAY_READ; |
| if (flags & S_IWUGO) |
| may |= MAY_WRITE; |
| if (flags & S_IXUGO) |
| may |= MAY_EXEC; |
| |
| return may; |
| } |
| |
| /** |
| * smack_msg_msg_alloc_security - Set the security blob for msg_msg |
| * @msg: the object |
| * |
| * Returns 0 |
| */ |
| static int smack_msg_msg_alloc_security(struct msg_msg *msg) |
| { |
| msg->security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_msg_msg_free_security - Clear the security blob for msg_msg |
| * @msg: the object |
| * |
| * Clears the blob pointer |
| */ |
| static void smack_msg_msg_free_security(struct msg_msg *msg) |
| { |
| msg->security = NULL; |
| } |
| |
| /** |
| * smack_of_shm - the smack pointer for the shm |
| * @shp: the object |
| * |
| * Returns a pointer to the smack value |
| */ |
| static char *smack_of_shm(struct shmid_kernel *shp) |
| { |
| return (char *)shp->shm_perm.security; |
| } |
| |
| /** |
| * smack_shm_alloc_security - Set the security blob for shm |
| * @shp: the object |
| * |
| * Returns 0 |
| */ |
| static int smack_shm_alloc_security(struct shmid_kernel *shp) |
| { |
| struct kern_ipc_perm *isp = &shp->shm_perm; |
| |
| isp->security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_shm_free_security - Clear the security blob for shm |
| * @shp: the object |
| * |
| * Clears the blob pointer |
| */ |
| static void smack_shm_free_security(struct shmid_kernel *shp) |
| { |
| struct kern_ipc_perm *isp = &shp->shm_perm; |
| |
| isp->security = NULL; |
| } |
| |
| /** |
| * smack_shm_associate - Smack access check for shm |
| * @shp: the object |
| * @shmflg: access requested |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) |
| { |
| char *ssp = smack_of_shm(shp); |
| int may; |
| |
| may = smack_flags_to_may(shmflg); |
| return smk_curacc(ssp, may); |
| } |
| |
| /** |
| * smack_shm_shmctl - Smack access check for shm |
| * @shp: the object |
| * @cmd: what it wants to do |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) |
| { |
| char *ssp; |
| int may; |
| |
| switch (cmd) { |
| case IPC_STAT: |
| case SHM_STAT: |
| may = MAY_READ; |
| break; |
| case IPC_SET: |
| case SHM_LOCK: |
| case SHM_UNLOCK: |
| case IPC_RMID: |
| may = MAY_READWRITE; |
| break; |
| case IPC_INFO: |
| case SHM_INFO: |
| /* |
| * System level information. |
| */ |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| |
| ssp = smack_of_shm(shp); |
| return smk_curacc(ssp, may); |
| } |
| |
| /** |
| * smack_shm_shmat - Smack access for shmat |
| * @shp: the object |
| * @shmaddr: unused |
| * @shmflg: access requested |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, |
| int shmflg) |
| { |
| char *ssp = smack_of_shm(shp); |
| int may; |
| |
| may = smack_flags_to_may(shmflg); |
| return smk_curacc(ssp, may); |
| } |
| |
| /** |
| * smack_of_sem - the smack pointer for the sem |
| * @sma: the object |
| * |
| * Returns a pointer to the smack value |
| */ |
| static char *smack_of_sem(struct sem_array *sma) |
| { |
| return (char *)sma->sem_perm.security; |
| } |
| |
| /** |
| * smack_sem_alloc_security - Set the security blob for sem |
| * @sma: the object |
| * |
| * Returns 0 |
| */ |
| static int smack_sem_alloc_security(struct sem_array *sma) |
| { |
| struct kern_ipc_perm *isp = &sma->sem_perm; |
| |
| isp->security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_sem_free_security - Clear the security blob for sem |
| * @sma: the object |
| * |
| * Clears the blob pointer |
| */ |
| static void smack_sem_free_security(struct sem_array *sma) |
| { |
| struct kern_ipc_perm *isp = &sma->sem_perm; |
| |
| isp->security = NULL; |
| } |
| |
| /** |
| * smack_sem_associate - Smack access check for sem |
| * @sma: the object |
| * @semflg: access requested |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_sem_associate(struct sem_array *sma, int semflg) |
| { |
| char *ssp = smack_of_sem(sma); |
| int may; |
| |
| may = smack_flags_to_may(semflg); |
| return smk_curacc(ssp, may); |
| } |
| |
| /** |
| * smack_sem_shmctl - Smack access check for sem |
| * @sma: the object |
| * @cmd: what it wants to do |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_sem_semctl(struct sem_array *sma, int cmd) |
| { |
| char *ssp; |
| int may; |
| |
| switch (cmd) { |
| case GETPID: |
| case GETNCNT: |
| case GETZCNT: |
| case GETVAL: |
| case GETALL: |
| case IPC_STAT: |
| case SEM_STAT: |
| may = MAY_READ; |
| break; |
| case SETVAL: |
| case SETALL: |
| case IPC_RMID: |
| case IPC_SET: |
| may = MAY_READWRITE; |
| break; |
| case IPC_INFO: |
| case SEM_INFO: |
| /* |
| * System level information |
| */ |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| |
| ssp = smack_of_sem(sma); |
| return smk_curacc(ssp, may); |
| } |
| |
| /** |
| * smack_sem_semop - Smack checks of semaphore operations |
| * @sma: the object |
| * @sops: unused |
| * @nsops: unused |
| * @alter: unused |
| * |
| * Treated as read and write in all cases. |
| * |
| * Returns 0 if access is allowed, error code otherwise |
| */ |
| static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, |
| unsigned nsops, int alter) |
| { |
| char *ssp = smack_of_sem(sma); |
| |
| return smk_curacc(ssp, MAY_READWRITE); |
| } |
| |
| /** |
| * smack_msg_alloc_security - Set the security blob for msg |
| * @msq: the object |
| * |
| * Returns 0 |
| */ |
| static int smack_msg_queue_alloc_security(struct msg_queue *msq) |
| { |
| struct kern_ipc_perm *kisp = &msq->q_perm; |
| |
| kisp->security = current_security(); |
| return 0; |
| } |
| |
| /** |
| * smack_msg_free_security - Clear the security blob for msg |
| * @msq: the object |
| * |
| * Clears the blob pointer |
| */ |
| static void smack_msg_queue_free_security(struct msg_queue *msq) |
| { |
| struct kern_ipc_perm *kisp = &msq->q_perm; |
| |
| kisp->security = NULL; |
| } |
| |
| /** |
| * smack_of_msq - the smack pointer for the msq |
| * @msq: the object |
| * |
| * Returns a pointer to the smack value |
| */ |
| static char *smack_of_msq(struct msg_queue *msq) |
| { |
| return (char *)msq->q_perm.security; |
| } |
| |
| /** |
| * smack_msg_queue_associate - Smack access check for msg_queue |
| * @msq: the object |
| * @msqflg: access requested |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) |
| { |
| char *msp = smack_of_msq(msq); |
| int may; |
| |
| may = smack_flags_to_may(msqflg); |
| return smk_curacc(msp, may); |
| } |
| |
| /** |
| * smack_msg_queue_msgctl - Smack access check for msg_queue |
| * @msq: the object |
| * @cmd: what it wants to do |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) |
| { |
| char *msp; |
| int may; |
| |
| switch (cmd) { |
| case IPC_STAT: |
| case MSG_STAT: |
| may = MAY_READ; |
| break; |
| case IPC_SET: |
| case IPC_RMID: |
| may = MAY_READWRITE; |
| break; |
| case IPC_INFO: |
| case MSG_INFO: |
| /* |
| * System level information |
| */ |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| |
| msp = smack_of_msq(msq); |
| return smk_curacc(msp, may); |
| } |
| |
| /** |
| * smack_msg_queue_msgsnd - Smack access check for msg_queue |
| * @msq: the object |
| * @msg: unused |
| * @msqflg: access requested |
| * |
| * Returns 0 if current has the requested access, error code otherwise |
| */ |
| static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, |
| int msqflg) |
| { |
| char *msp = smack_of_msq(msq); |
| int rc; |
| |
| rc = smack_flags_to_may(msqflg); |
| return smk_curacc(msp, rc); |
| } |
| |
| /** |
| * smack_msg_queue_msgsnd - Smack access check for msg_queue |
| * @msq: the object |
| * @msg: unused |
| * @target: unused |
| * @type: unused |
| * @mode: unused |
| * |
| * Returns 0 if current has read and write access, error code otherwise |
| */ |
| static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, |
| struct task_struct *target, long type, int mode) |
| { |
| char *msp = smack_of_msq(msq); |
| |
| return smk_curacc(msp, MAY_READWRITE); |
| } |
| |
| /** |
| * smack_ipc_permission - Smack access for ipc_permission() |
| * @ipp: the object permissions |
| * @flag: access requested |
| * |
| * Returns 0 if current has read and write access, error code otherwise |
| */ |
| static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) |
| { |
| char *isp = ipp->security; |
| int may; |
| |
| may = smack_flags_to_may(flag); |
| return smk_curacc(isp, may); |
| } |
| |
| /** |
| * smack_ipc_getsecid - Extract smack security id |
| * @ipcp: the object permissions |
| * @secid: where result will be saved |
| */ |
| static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) |
| { |
| char *smack = ipp->security; |
| |
| *secid = smack_to_secid(smack); |
| } |
| |
| /** |
| * smack_d_instantiate - Make sure the blob is correct on an inode |
| * @opt_dentry: unused |
| * @inode: the object |
| * |
| * Set the inode's security blob if it hasn't been done already. |
| */ |
| static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) |
| { |
| struct super_block *sbp; |
| struct superblock_smack *sbsp; |
| struct inode_smack *isp; |
| char *csp = current_security(); |
| char *fetched; |
| char *final; |
| struct dentry *dp; |
| |
| if (inode == NULL) |
| return; |
| |
| isp = inode->i_security; |
| |
| mutex_lock(&isp->smk_lock); |
| /* |
| * If the inode is already instantiated |
| * take the quick way out |
| */ |
| if (isp->smk_flags & SMK_INODE_INSTANT) |
| goto unlockandout; |
| |
| sbp = inode->i_sb; |
| sbsp = sbp->s_security; |
| /* |
| * We're going to use the superblock default label |
| * if there's no label on the file. |
| */ |
| final = sbsp->smk_default; |
| |
| /* |
| * If this is the root inode the superblock |
| * may be in the process of initialization. |
| * If that is the case use the root value out |
| * of the superblock. |
| */ |
| if (opt_dentry->d_parent == opt_dentry) { |
| isp->smk_inode = sbsp->smk_root; |
| isp->smk_flags |= SMK_INODE_INSTANT; |
| goto unlockandout; |
| } |
| |
| /* |
| * This is pretty hackish. |
| * Casey says that we shouldn't have to do |
| * file system specific code, but it does help |
| * with keeping it simple. |
| */ |
| switch (sbp->s_magic) { |
| case SMACK_MAGIC: |
| /* |
| * Casey says that it's a little embarassing |
| * that the smack file system doesn't do |
| * extended attributes. |
| */ |
| final = smack_known_star.smk_known; |
| break; |
| case PIPEFS_MAGIC: |
| /* |
| * Casey says pipes are easy (?) |
| */ |
| final = smack_known_star.smk_known; |
| break; |
| case DEVPTS_SUPER_MAGIC: |
| /* |
| * devpts seems content with the label of the task. |
| * Programs that change smack have to treat the |
| * pty with respect. |
| */ |
| final = csp; |
| break; |
| case SOCKFS_MAGIC: |
| /* |
| * Casey says sockets get the smack of the task. |
| */ |
| final = csp; |
| break; |
| case PROC_SUPER_MAGIC: |
| /* |
| * Casey says procfs appears not to care. |
| * The superblock default suffices. |
| */ |
| break; |
| case TMPFS_MAGIC: |
| /* |
| * Device labels should come from the filesystem, |
| * but watch out, because they're volitile, |
| * getting recreated on every reboot. |
| */ |
| final = smack_known_star.smk_known; |
| /* |
| * No break. |
| * |
| * If a smack value has been set we want to use it, |
| * but since tmpfs isn't giving us the opportunity |
| * to set mount options simulate setting the |
| * superblock default. |
| */ |
| default: |
| /* |
| * This isn't an understood special case. |
| * Get the value from the xattr. |
| * |
| * No xattr support means, alas, no SMACK label. |
| * Use the aforeapplied default. |
| * It would be curious if the label of the task |
| * does not match that assigned. |
| */ |
| if (inode->i_op->getxattr == NULL) |
| break; |
| /* |
| * Get the dentry for xattr. |
| */ |
| if (opt_dentry == NULL) { |
| dp = d_find_alias(inode); |
| if (dp == NULL) |
| break; |
| } else { |
| dp = dget(opt_dentry); |
| if (dp == NULL) |
| break; |
| } |
| |
| fetched = smk_fetch(inode, dp); |
| if (fetched != NULL) |
| final = fetched; |
| |
| dput(dp); |
| break; |
| } |
| |
| if (final == NULL) |
| isp->smk_inode = csp; |
| else |
| isp->smk_inode = final; |
| |
| isp->smk_flags |= SMK_INODE_INSTANT; |
| |
| unlockandout: |
| mutex_unlock(&isp->smk_lock); |
| return; |
| } |
| |
| /** |
| * smack_getprocattr - Smack process attribute access |
| * @p: the object task |
| * @name: the name of the attribute in /proc/.../attr |
| * @value: where to put the result |
| * |
| * Places a copy of the task Smack into value |
| * |
| * Returns the length of the smack label or an error code |
| */ |
| static int smack_getprocattr(struct task_struct *p, char *name, char **value) |
| { |
| char *cp; |
| int slen; |
| |
| if (strcmp(name, "current") != 0) |
| return -EINVAL; |
| |
| cp = kstrdup(task_security(p), GFP_KERNEL); |
| if (cp == NULL) |
| return -ENOMEM; |
| |
| slen = strlen(cp); |
| *value = cp; |
| return slen; |
| } |
| |
| /** |
| * smack_setprocattr - Smack process attribute setting |
| * @p: the object task |
| * @name: the name of the attribute in /proc/.../attr |
| * @value: the value to set |
| * @size: the size of the value |
| * |
| * Sets the Smack value of the task. Only setting self |
| * is permitted and only with privilege |
| * |
| * Returns the length of the smack label or an error code |
| */ |
| static int smack_setprocattr(struct task_struct *p, char *name, |
| void *value, size_t size) |
| { |
| struct cred *new; |
| char *newsmack; |
| |
| /* |
| * Changing another process' Smack value is too dangerous |
| * and supports no sane use case. |
| */ |
| if (p != current) |
| return -EPERM; |
| |
| if (!capable(CAP_MAC_ADMIN)) |
| return -EPERM; |
| |
| if (value == NULL || size == 0 || size >= SMK_LABELLEN) |
| return -EINVAL; |
| |
| if (strcmp(name, "current") != 0) |
| return -EINVAL; |
| |
| newsmack = smk_import(value, size); |
| if (newsmack == NULL) |
| return -EINVAL; |
| |
| /* |
| * No process is ever allowed the web ("@") label. |
| */ |
| if (newsmack == smack_known_web.smk_known) |
| return -EPERM; |
| |
| new = prepare_creds(); |
| if (new == NULL) |
| return -ENOMEM; |
| new->security = newsmack; |
| commit_creds(new); |
| return size; |
| } |
| |
| /** |
| * smack_unix_stream_connect - Smack access on UDS |
| * @sock: one socket |
| * @other: the other socket |
| * @newsk: unused |
| * |
| * Return 0 if a subject with the smack of sock could access |
| * an object with the smack of other, otherwise an error code |
| */ |
| static int smack_unix_stream_connect(struct socket *sock, |
| struct socket *other, struct sock *newsk) |
| { |
| struct inode *sp = SOCK_INODE(sock); |
| struct inode *op = SOCK_INODE(other); |
| |
| return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE); |
| } |
| |
| /** |
| * smack_unix_may_send - Smack access on UDS |
| * @sock: one socket |
| * @other: the other socket |
| * |
| * Return 0 if a subject with the smack of sock could access |
| * an object with the smack of other, otherwise an error code |
| */ |
| static int smack_unix_may_send(struct socket *sock, struct socket *other) |
| { |
| struct inode *sp = SOCK_INODE(sock); |
| struct inode *op = SOCK_INODE(other); |
| |
| return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE); |
| } |
| |
| /** |
| * smack_socket_sendmsg - Smack check based on destination host |
| * @sock: the socket |
| * @msghdr: the message |
| * @size: the size of the message |
| * |
| * Return 0 if the current subject can write to the destination |
| * host. This is only a question if the destination is a single |
| * label host. |
| */ |
| static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, |
| int size) |
| { |
| struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; |
| struct socket_smack *ssp = sock->sk->sk_security; |
| char *hostsp; |
| int rc; |
| |
| /* |
| * Perfectly reasonable for this to be NULL |
| */ |
| if (sip == NULL || sip->sin_family != PF_INET) |
| return 0; |
| |
| hostsp = smack_host_label(sip); |
| if (hostsp == NULL) { |
| if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) |
| return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); |
| return 0; |
| } |
| |
| rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); |
| if (rc != 0) |
| return rc; |
| |
| if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) |
| return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); |
| |
| return 0; |
| |
| } |
| |
| |
| /** |
| * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat |
| * pair to smack |
| * @sap: netlabel secattr |
| * @sip: where to put the result |
| * |
| * Copies a smack label into sip |
| */ |
| static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip) |
| { |
| char smack[SMK_LABELLEN]; |
| char *sp; |
| int pcat; |
| |
| if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { |
| /* |
| * Looks like a CIPSO packet. |
| * If there are flags but no level netlabel isn't |
| * behaving the way we expect it to. |
| * |
| * Get the categories, if any |
| * Without guidance regarding the smack value |
| * for the packet fall back on the network |
| * ambient value. |
| */ |
| memset(smack, '\0', SMK_LABELLEN); |
| if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0) |
| for (pcat = -1;;) { |
| pcat = netlbl_secattr_catmap_walk( |
| sap->attr.mls.cat, pcat + 1); |
| if (pcat < 0) |
| break; |
| smack_catset_bit(pcat, smack); |
| } |
| /* |
| * If it is CIPSO using smack direct mapping |
| * we are already done. WeeHee. |
| */ |
| if (sap->attr.mls.lvl == smack_cipso_direct) { |
| memcpy(sip, smack, SMK_MAXLEN); |
| return; |
| } |
| /* |
| * Look it up in the supplied table if it is not |
| * a direct mapping. |
| */ |
| smack_from_cipso(sap->attr.mls.lvl, smack, sip); |
| return; |
| } |
| if ((sap->flags & NETLBL_SECATTR_SECID) != 0) { |
| /* |
| * Looks like a fallback, which gives us a secid. |
| */ |
| sp = smack_from_secid(sap->attr.secid); |
| /* |
| * This has got to be a bug because it is |
| * impossible to specify a fallback without |
| * specifying the label, which will ensure |
| * it has a secid, and the only way to get a |
| * secid is from a fallback. |
| */ |
| BUG_ON(sp == NULL); |
| strncpy(sip, sp, SMK_MAXLEN); |
| return; |
| } |
| /* |
| * Without guidance regarding the smack value |
| * for the packet fall back on the network |
| * ambient value. |
| */ |
| strncpy(sip, smack_net_ambient, SMK_MAXLEN); |
| return; |
| } |
| |
| /** |
| * smack_socket_sock_rcv_skb - Smack packet delivery access check |
| * @sk: socket |
| * @skb: packet |
| * |
| * Returns 0 if the packet should be delivered, an error code otherwise |
| */ |
| static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) |
| { |
| struct netlbl_lsm_secattr secattr; |
| struct socket_smack *ssp = sk->sk_security; |
| char smack[SMK_LABELLEN]; |
| char *csp; |
| int rc; |
| |
| if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) |
| return 0; |
| |
| /* |
| * Translate what netlabel gave us. |
| */ |
| netlbl_secattr_init(&secattr); |
| |
| rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); |
| if (rc == 0) { |
| smack_from_secattr(&secattr, smack); |
| csp = smack; |
| } else |
| csp = smack_net_ambient; |
| |
| netlbl_secattr_destroy(&secattr); |
| |
| /* |
| * Receiving a packet requires that the other end |
| * be able to write here. Read access is not required. |
| * This is the simplist possible security model |
| * for networking. |
| */ |
| rc = smk_access(csp, ssp->smk_in, MAY_WRITE); |
| if (rc != 0) |
| netlbl_skbuff_err(skb, rc, 0); |
| return rc; |
| } |
| |
| /** |
| * smack_socket_getpeersec_stream - pull in packet label |
| * @sock: the socket |
| * @optval: user's destination |
| * @optlen: size thereof |
| * @len: max thereoe |
| * |
| * returns zero on success, an error code otherwise |
| */ |
| static int smack_socket_getpeersec_stream(struct socket *sock, |
| char __user *optval, |
| int __user *optlen, unsigned len) |
| { |
| struct socket_smack *ssp; |
| int slen; |
| int rc = 0; |
| |
| ssp = sock->sk->sk_security; |
| slen = strlen(ssp->smk_packet) + 1; |
| |
| if (slen > len) |
| rc = -ERANGE; |
| else if (copy_to_user(optval, ssp->smk_packet, slen) != 0) |
| rc = -EFAULT; |
| |
| if (put_user(slen, optlen) != 0) |
| rc = -EFAULT; |
| |
| return rc; |
| } |
| |
| |
| /** |
| * smack_socket_getpeersec_dgram - pull in packet label |
| * @sock: the socket |
| * @skb: packet data |
| * @secid: pointer to where to put the secid of the packet |
| * |
| * Sets the netlabel socket state on sk from parent |
| */ |
| static int smack_socket_getpeersec_dgram(struct socket *sock, |
| struct sk_buff *skb, u32 *secid) |
| |
| { |
| struct netlbl_lsm_secattr secattr; |
| struct sock *sk; |
| char smack[SMK_LABELLEN]; |
| int family = PF_INET; |
| u32 s; |
| int rc; |
| |
| /* |
| * Only works for families with packets. |
| */ |
| if (sock != NULL) { |
| sk = sock->sk; |
| if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) |
| return 0; |
| family = sk->sk_family; |
| } |
| /* |
| * Translate what netlabel gave us. |
| */ |
| netlbl_secattr_init(&secattr); |
| rc = netlbl_skbuff_getattr(skb, family, &secattr); |
| if (rc == 0) |
| smack_from_secattr(&secattr, smack); |
| netlbl_secattr_destroy(&secattr); |
| |
| /* |
| * Give up if we couldn't get anything |
| */ |
| if (rc != 0) |
| return rc; |
| |
| s = smack_to_secid(smack); |
| if (s == 0) |
| return -EINVAL; |
| |
| *secid = s; |
| return 0; |
| } |
| |
| /** |
| * smack_sock_graft - graft access state between two sockets |
| * @sk: fresh sock |
| * @parent: donor socket |
| * |
| * Sets the netlabel socket state on sk from parent |
| */ |
| static void smack_sock_graft(struct sock *sk, struct socket *parent) |
| { |
| struct socket_smack *ssp; |
| int rc; |
| |
| if (sk == NULL) |
| return; |
| |
| if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) |
| return; |
| |
| ssp = sk->sk_security; |
| ssp->smk_in = ssp->smk_out = current_security(); |
| ssp->smk_packet[0] = '\0'; |
| |
| rc = smack_netlabel(sk, SMACK_CIPSO_SOCKET); |
| if (rc != 0) |
| printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", |
| __func__, -rc); |
| } |
| |
| /** |
| * smack_inet_conn_request - Smack access check on connect |
| * @sk: socket involved |
| * @skb: packet |
| * @req: unused |
| * |
| * Returns 0 if a task with the packet label could write to |
| * the socket, otherwise an error code |
| */ |
| static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, |
| struct request_sock *req) |
| { |
| struct netlbl_lsm_secattr skb_secattr; |
| struct socket_smack *ssp = sk->sk_security; |
| char smack[SMK_LABELLEN]; |
| int rc; |
| |
| if (skb == NULL) |
| return -EACCES; |
| |
| netlbl_secattr_init(&skb_secattr); |
| rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr); |
| if (rc == 0) |
| smack_from_secattr(&skb_secattr, smack); |
| else |
| strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); |
| netlbl_secattr_destroy(&skb_secattr); |
| /* |
| * Receiving a packet requires that the other end |
| * be able to write here. Read access is not required. |
| * |
| * If the request is successful save the peer's label |
| * so that SO_PEERCRED can report it. |
| */ |
| rc = smk_access(smack, ssp->smk_in, MAY_WRITE); |
| if (rc == 0) |
| strncpy(ssp->smk_packet, smack, SMK_MAXLEN); |
| |
| return rc; |
| } |
| |
| /* |
| * Key management security hooks |
| * |
| * Casey has not tested key support very heavily. |
| * The permission check is most likely too restrictive. |
| * If you care about keys please have a look. |
| */ |
| #ifdef CONFIG_KEYS |
| |
| /** |
| * smack_key_alloc - Set the key security blob |
| * @key: object |
| * @cred: the credentials to use |
| * @flags: unused |
| * |
| * No allocation required |
| * |
| * Returns 0 |
| */ |
| static int smack_key_alloc(struct key *key, const struct cred *cred, |
| unsigned long flags) |
| { |
| key->security = cred->security; |
| return 0; |
| } |
| |
| /** |
| * smack_key_free - Clear the key security blob |
| * @key: the object |
| * |
| * Clear the blob pointer |
| */ |
| static void smack_key_free(struct key *key) |
| { |
| key->security = NULL; |
| } |
| |
| /* |
| * smack_key_permission - Smack access on a key |
| * @key_ref: gets to the object |
| * @cred: the credentials to use |
| * @perm: unused |
| * |
| * Return 0 if the task has read and write to the object, |
| * an error code otherwise |
| */ |
| static int smack_key_permission(key_ref_t key_ref, |
| const struct cred *cred, key_perm_t perm) |
| { |
| struct key *keyp; |
| |
| keyp = key_ref_to_ptr(key_ref); |
| if (keyp == NULL) |
| return -EINVAL; |
| /* |
| * If the key hasn't been initialized give it access so that |
| * it may do so. |
| */ |
| if (keyp->security == NULL) |
| return 0; |
| /* |
| * This should not occur |
| */ |
| if (cred->security == NULL) |
| return -EACCES; |
| |
| return smk_access(cred->security, keyp->security, MAY_READWRITE); |
| } |
| #endif /* CONFIG_KEYS */ |
| |
| /* |
| * Smack Audit hooks |
| * |
| * Audit requires a unique representation of each Smack specific |
| * rule. This unique representation is used to distinguish the |
| * object to be audited from remaining kernel objects and also |
| * works as a glue between the audit hooks. |
| * |
| * Since repository entries are added but never deleted, we'll use |
| * the smack_known label address related to the given audit rule as |
| * the needed unique representation. This also better fits the smack |
| * model where nearly everything is a label. |
| */ |
| #ifdef CONFIG_AUDIT |
| |
| /** |
| * smack_audit_rule_init - Initialize a smack audit rule |
| * @field: audit rule fields given from user-space (audit.h) |
| * @op: required testing operator (=, !=, >, <, ...) |
| * @rulestr: smack label to be audited |
| * @vrule: pointer to save our own audit rule representation |
| * |
| * Prepare to audit cases where (@field @op @rulestr) is true. |
| * The label to be audited is created if necessay. |
| */ |
| static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) |
| { |
| char **rule = (char **)vrule; |
| *rule = NULL; |
| |
| if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) |
| return -EINVAL; |
| |
| if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL) |
| return -EINVAL; |
| |
| *rule = smk_import(rulestr, 0); |
| |
| return 0; |
| } |
| |
| /** |
| * smack_audit_rule_known - Distinguish Smack audit rules |
| * @krule: rule of interest, in Audit kernel representation format |
| * |
| * This is used to filter Smack rules from remaining Audit ones. |
| * If it's proved that this rule belongs to us, the |
| * audit_rule_match hook will be called to do the final judgement. |
| */ |
| static int smack_audit_rule_known(struct audit_krule *krule) |
| { |
| struct audit_field *f; |
| int i; |
| |
| for (i = 0; i < krule->field_count; i++) { |
| f = &krule->fields[i]; |
| |
| if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * smack_audit_rule_match - Audit given object ? |
| * @secid: security id for identifying the object to test |
| * @field: audit rule flags given from user-space |
| * @op: required testing operator |
| * @vrule: smack internal rule presentation |
| * @actx: audit context associated with the check |
| * |
| * The core Audit hook. It's used to take the decision of |
| * whether to audit or not to audit a given object. |
| */ |
| static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule, |
| struct audit_context *actx) |
| { |
| char *smack; |
| char *rule = vrule; |
| |
| if (!rule) { |
| audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR, |
| "Smack: missing rule\n"); |
| return -ENOENT; |
| } |
| |
| if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) |
| return 0; |
| |
| smack = smack_from_secid(secid); |
| |
| /* |
| * No need to do string comparisons. If a match occurs, |
| * both pointers will point to the same smack_known |
| * label. |
| */ |
| if (op == AUDIT_EQUAL) |
| return (rule == smack); |
| if (op == AUDIT_NOT_EQUAL) |
| return (rule != smack); |
| |
| return 0; |
| } |
| |
| /** |
| * smack_audit_rule_free - free smack rule representation |
| * @vrule: rule to be freed. |
| * |
| * No memory was allocated. |
| */ |
| static void smack_audit_rule_free(void *vrule) |
| { |
| /* No-op */ |
| } |
| |
| #endif /* CONFIG_AUDIT */ |
| |
| /* |
| * smack_secid_to_secctx - return the smack label for a secid |
| * @secid: incoming integer |
| * @secdata: destination |
| * @seclen: how long it is |
| * |
| * Exists for networking code. |
| */ |
| static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) |
| { |
| char *sp = smack_from_secid(secid); |
| |
| *secdata = sp; |
| *seclen = strlen(sp); |
| return 0; |
| } |
| |
| /* |
| * smack_secctx_to_secid - return the secid for a smack label |
| * @secdata: smack label |
| * @seclen: how long result is |
| * @secid: outgoing integer |
| * |
| * Exists for audit and networking code. |
| */ |
| static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) |
| { |
| *secid = smack_to_secid(secdata); |
| return 0; |
| } |
| |
| /* |
| * smack_release_secctx - don't do anything. |
| * @key_ref: unused |
| * @context: unused |
| * @perm: unused |
| * |
| * Exists to make sure nothing gets done, and properly |
| */ |
| static void smack_release_secctx(char *secdata, u32 seclen) |
| { |
| } |
| |
| struct security_operations smack_ops = { |
| .name = "smack", |
| |
| .ptrace_may_access = smack_ptrace_may_access, |
| .ptrace_traceme = smack_ptrace_traceme, |
| .capget = cap_capget, |
| .capset = cap_capset, |
| .capable = cap_capable, |
| .task_capable = cap_task_capable, |
| .syslog = smack_syslog, |
| .settime = cap_settime, |
| .vm_enough_memory = cap_vm_enough_memory, |
| |
| .bprm_set_creds = cap_bprm_set_creds, |
| .bprm_secureexec = cap_bprm_secureexec, |
| |
| .sb_alloc_security = smack_sb_alloc_security, |
| .sb_free_security = smack_sb_free_security, |
| .sb_copy_data = smack_sb_copy_data, |
| .sb_kern_mount = smack_sb_kern_mount, |
| .sb_statfs = smack_sb_statfs, |
| .sb_mount = smack_sb_mount, |
| .sb_umount = smack_sb_umount, |
| |
| .inode_alloc_security = smack_inode_alloc_security, |
| .inode_free_security = smack_inode_free_security, |
| .inode_init_security = smack_inode_init_security, |
| .inode_link = smack_inode_link, |
| .inode_unlink = smack_inode_unlink, |
| .inode_rmdir = smack_inode_rmdir, |
| .inode_rename = smack_inode_rename, |
| .inode_permission = smack_inode_permission, |
| .inode_setattr = smack_inode_setattr, |
| .inode_getattr = smack_inode_getattr, |
| .inode_setxattr = smack_inode_setxattr, |
| .inode_post_setxattr = smack_inode_post_setxattr, |
| .inode_getxattr = smack_inode_getxattr, |
| .inode_removexattr = smack_inode_removexattr, |
| .inode_need_killpriv = cap_inode_need_killpriv, |
| .inode_killpriv = cap_inode_killpriv, |
| .inode_getsecurity = smack_inode_getsecurity, |
| .inode_setsecurity = smack_inode_setsecurity, |
| .inode_listsecurity = smack_inode_listsecurity, |
| .inode_getsecid = smack_inode_getsecid, |
| |
| .file_permission = smack_file_permission, |
| .file_alloc_security = smack_file_alloc_security, |
| .file_free_security = smack_file_free_security, |
| .file_ioctl = smack_file_ioctl, |
| .file_lock = smack_file_lock, |
| .file_fcntl = smack_file_fcntl, |
| .file_set_fowner = smack_file_set_fowner, |
| .file_send_sigiotask = smack_file_send_sigiotask, |
| .file_receive = smack_file_receive, |
| |
| .cred_free = smack_cred_free, |
| .cred_prepare = smack_cred_prepare, |
| .cred_commit = smack_cred_commit, |
| .kernel_act_as = smack_kernel_act_as, |
| .kernel_create_files_as = smack_kernel_create_files_as, |
| .task_fix_setuid = cap_task_fix_setuid, |
| .task_setpgid = smack_task_setpgid, |
| .task_getpgid = smack_task_getpgid, |
| .task_getsid = smack_task_getsid, |
| .task_getsecid = smack_task_getsecid, |
| .task_setnice = smack_task_setnice, |
| .task_setioprio = smack_task_setioprio, |
| .task_getioprio = smack_task_getioprio, |
| .task_setscheduler = smack_task_setscheduler, |
| .task_getscheduler = smack_task_getscheduler, |
| .task_movememory = smack_task_movememory, |
| .task_kill = smack_task_kill, |
| .task_wait = smack_task_wait, |
| .task_to_inode = smack_task_to_inode, |
| .task_prctl = cap_task_prctl, |
| |
| .ipc_permission = smack_ipc_permission, |
| .ipc_getsecid = smack_ipc_getsecid, |
| |
| .msg_msg_alloc_security = smack_msg_msg_alloc_security, |
| .msg_msg_free_security = smack_msg_msg_free_security, |
| |
| .msg_queue_alloc_security = smack_msg_queue_alloc_security, |
| .msg_queue_free_security = smack_msg_queue_free_security, |
| .msg_queue_associate = smack_msg_queue_associate, |
| .msg_queue_msgctl = smack_msg_queue_msgctl, |
| .msg_queue_msgsnd = smack_msg_queue_msgsnd, |
| .msg_queue_msgrcv = smack_msg_queue_msgrcv, |
| |
| .shm_alloc_security = smack_shm_alloc_security, |
| .shm_free_security = smack_shm_free_security, |
| .shm_associate = smack_shm_associate, |
| .shm_shmctl = smack_shm_shmctl, |
| .shm_shmat = smack_shm_shmat, |
| |
| .sem_alloc_security = smack_sem_alloc_security, |
| .sem_free_security = smack_sem_free_security, |
| .sem_associate = smack_sem_associate, |
| .sem_semctl = smack_sem_semctl, |
| .sem_semop = smack_sem_semop, |
| |
| .netlink_send = cap_netlink_send, |
| .netlink_recv = cap_netlink_recv, |
| |
| .d_instantiate = smack_d_instantiate, |
| |
| .getprocattr = smack_getprocattr, |
| .setprocattr = smack_setprocattr, |
| |
| .unix_stream_connect = smack_unix_stream_connect, |
| .unix_may_send = smack_unix_may_send, |
| |
| .socket_post_create = smack_socket_post_create, |
| .socket_connect = smack_socket_connect, |
| .socket_sendmsg = smack_socket_sendmsg, |
| .socket_sock_rcv_skb = smack_socket_sock_rcv_skb, |
| .socket_getpeersec_stream = smack_socket_getpeersec_stream, |
| .socket_getpeersec_dgram = smack_socket_getpeersec_dgram, |
| .sk_alloc_security = smack_sk_alloc_security, |
| .sk_free_security = smack_sk_free_security, |
| .sock_graft = smack_sock_graft, |
| .inet_conn_request = smack_inet_conn_request, |
| |
| /* key management security hooks */ |
| #ifdef CONFIG_KEYS |
| .key_alloc = smack_key_alloc, |
| .key_free = smack_key_free, |
| .key_permission = smack_key_permission, |
| #endif /* CONFIG_KEYS */ |
| |
| /* Audit hooks */ |
| #ifdef CONFIG_AUDIT |
| .audit_rule_init = smack_audit_rule_init, |
| .audit_rule_known = smack_audit_rule_known, |
| .audit_rule_match = smack_audit_rule_match, |
| .audit_rule_free = smack_audit_rule_free, |
| #endif /* CONFIG_AUDIT */ |
| |
| .secid_to_secctx = smack_secid_to_secctx, |
| .secctx_to_secid = smack_secctx_to_secid, |
| .release_secctx = smack_release_secctx, |
| }; |
| |
| /** |
| * smack_init - initialize the smack system |
| * |
| * Returns 0 |
| */ |
| static __init int smack_init(void) |
| { |
| struct cred *cred; |
| |
| if (!security_module_enable(&smack_ops)) |
| return 0; |
| |
| printk(KERN_INFO "Smack: Initializing.\n"); |
| |
| /* |
| * Set the security state for the initial task. |
| */ |
| cred = (struct cred *) current->cred; |
| cred->security = &smack_known_floor.smk_known; |
| |
| /* |
| * Initialize locks |
| */ |
| spin_lock_init(&smack_known_huh.smk_cipsolock); |
| spin_lock_init(&smack_known_hat.smk_cipsolock); |
| spin_lock_init(&smack_known_star.smk_cipsolock); |
| spin_lock_init(&smack_known_floor.smk_cipsolock); |
| spin_lock_init(&smack_known_invalid.smk_cipsolock); |
| |
| /* |
| * Register with LSM |
| */ |
| if (register_security(&smack_ops)) |
| panic("smack: Unable to register with kernel.\n"); |
| |
| return 0; |
| } |
| |
| /* |
| * Smack requires early initialization in order to label |
| * all processes and objects when they are created. |
| */ |
| security_initcall(smack_init); |