litmus-rt.git - The LITMUS^RT kernel.

	Commit message (Expand)	Author	Age
*	NFS: Share NFS superblocks per-protocol per-server per-FSID	David Howells	2006-09-22
*	NFS: Add extra const qualifiers	David Howells	2006-09-22
*	NFS: Split fs/nfs/inode.c	David Howells	2006-06-09

/* * Simplified MAC Kernel (smack) security module * * This file contains the smack hook function implementations. * * Authors: * Casey Schaufler <casey@schaufler-ca.com> * Jarkko Sakkinen <jarkko.sakkinen@intel.com> * * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. * Paul Moore <paul@paul-moore.com> * Copyright (C) 2010 Nokia Corporation * Copyright (C) 2011 Intel Corporation. * * 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/kd.h> #include <asm/ioctls.h> #include <linux/ip.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/dccp.h> #include <linux/slab.h> #include <linux/mutex.h> #include <linux/pipe_fs_i.h> #include <net/cipso_ipv4.h> #include <net/ip.h> #include <net/ipv6.h> #include <linux/audit.h> #include <linux/magic.h> #include <linux/dcache.h> #include <linux/personality.h> #include <linux/msg.h> #include <linux/shm.h> #include <linux/binfmts.h> #include "smack.h" #define task_security(task) (task_cred_xxx((task), security)) #define TRANS_TRUE "TRUE" #define TRANS_TRUE_SIZE 4 #define SMK_CONNECTING 0 #define SMK_RECEIVING 1 #define SMK_SENDING 2 LIST_HEAD(smk_ipv6_port_list); static struct kmem_cache *smack_inode_cache; #ifdef CONFIG_SECURITY_SMACK_BRINGUP static void smk_bu_mode(int mode, char *s) { int i = 0; if (mode & MAY_READ) s[i++] = 'r'; if (mode & MAY_WRITE) s[i++] = 'w'; if (mode & MAY_EXEC) s[i++] = 'x'; if (mode & MAY_APPEND) s[i++] = 'a'; if (mode & MAY_TRANSMUTE) s[i++] = 't'; if (mode & MAY_LOCK) s[i++] = 'l'; if (i == 0) s[i++] = '-'; s[i] = '\0'; } #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_note(char *note, struct smack_known *sskp, struct smack_known *oskp, int mode, int rc) { char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) %s\n", sskp->smk_known, oskp->smk_known, acc, note); return 0; } #else #define smk_bu_note(note, sskp, oskp, mode, RC) (RC) #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_current(char *note, struct smack_known *oskp, int mode, int rc) { struct task_smack *tsp = current_security(); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) %s %s\n", tsp->smk_task->smk_known, oskp->smk_known, acc, current->comm, note); return 0; } #else #define smk_bu_current(note, oskp, mode, RC) (RC) #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_task(struct task_struct *otp, int mode, int rc) { struct task_smack *tsp = current_security(); struct task_smack *otsp = task_security(otp); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) %s to %s\n", tsp->smk_task->smk_known, otsp->smk_task->smk_known, acc, current->comm, otp->comm); return 0; } #else #define smk_bu_task(otp, mode, RC) (RC) #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_inode(struct inode *inode, int mode, int rc) { struct task_smack *tsp = current_security(); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) inode=(%s %ld) %s\n", tsp->smk_task->smk_known, smk_of_inode(inode)->smk_known, acc, inode->i_sb->s_id, inode->i_ino, current->comm); return 0; } #else #define smk_bu_inode(inode, mode, RC) (RC) #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_file(struct file *file, int mode, int rc) { struct task_smack *tsp = current_security(); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file->f_inode; char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n", sskp->smk_known, (char *)file->f_security, acc, inode->i_sb->s_id, inode->i_ino, file, current->comm); return 0; } #else #define smk_bu_file(file, mode, RC) (RC) #endif #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_credfile(const struct cred *cred, struct file *file, int mode, int rc) { struct task_smack *tsp = cred->security; struct smack_known *sskp = tsp->smk_task; struct inode *inode = file->f_inode; char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) return rc; smk_bu_mode(mode, acc); pr_info("Smack Bringup: (%s %s %s) file=(%s %ld %pD) %s\n", sskp->smk_known, smk_of_inode(inode)->smk_known, acc, inode->i_sb->s_id, inode->i_ino, file, current->comm); return 0; } #else #define smk_bu_credfile(cred, file, mode, RC) (RC) #endif /** * smk_fetch - Fetch the smack label from a file. * @name: type of the label (attribute) * @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 struct smack_known *smk_fetch(const char *name, struct inode *ip, struct dentry *dp) { int rc; char *buffer; struct smack_known *skp = NULL; if (ip->i_op->getxattr == NULL) return NULL; buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL); if (buffer == NULL) return NULL; rc = ip->i_op->getxattr(dp, name, buffer, SMK_LONGLABEL); if (rc > 0) skp = smk_import_entry(buffer, rc); kfree(buffer); return skp; } /** * new_inode_smack - allocate an inode security blob * @skp: a pointer to the Smack label entry to use in the blob * * Returns the new blob or NULL if there's no memory available */ struct inode_smack *new_inode_smack(struct smack_known *skp) { struct inode_smack *isp; isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS); if (isp == NULL) return NULL; isp->smk_inode = skp; isp->smk_flags = 0; mutex_init(&isp->smk_lock); return isp; } /** * new_task_smack - allocate a task security blob * @task: a pointer to the Smack label for the running task * @forked: a pointer to the Smack label for the forked task * @gfp: type of the memory for the allocation * * Returns the new blob or NULL if there's no memory available */ static struct task_smack *new_task_smack(struct smack_known *task, struct smack_known *forked, gfp_t gfp) { struct task_smack *tsp; tsp = kzalloc(sizeof(struct task_smack), gfp); if (tsp == NULL) return NULL; tsp->smk_task = task; tsp->smk_forked = forked; INIT_LIST_HEAD(&tsp->smk_rules); mutex_init(&tsp->smk_rules_lock); return tsp; } /** * smk_copy_rules - copy a rule set * @nhead: new rules header pointer * @ohead: old rules header pointer * @gfp: type of the memory for the allocation * * Returns 0 on success, -ENOMEM on error */ static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead, gfp_t gfp) { struct smack_rule *nrp; struct smack_rule *orp; int rc = 0; INIT_LIST_HEAD(nhead); list_for_each_entry_rcu(orp, ohead, list) { nrp = kzalloc(sizeof(struct smack_rule), gfp); if (nrp == NULL) { rc = -ENOMEM; break; } *nrp = *orp; list_add_rcu(&nrp->list, nhead); } return rc; } /** * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_* * @mode - input mode in form of PTRACE_MODE_* * * Returns a converted MAY_* mode usable by smack rules */ static inline unsigned int smk_ptrace_mode(unsigned int mode) { switch (mode) { case PTRACE_MODE_READ: return MAY_READ; case PTRACE_MODE_ATTACH: return MAY_READWRITE; } return 0; } /** * smk_ptrace_rule_check - helper for ptrace access * @tracer: tracer process * @tracee_known: label entry of the process that's about to be traced * @mode: ptrace attachment mode (PTRACE_MODE_*) * @func: name of the function that called us, used for audit * * Returns 0 on access granted, -error on error */ static int smk_ptrace_rule_check(struct task_struct *tracer, struct smack_known *tracee_known, unsigned int mode, const char *func) { int rc; struct smk_audit_info ad, *saip = NULL; struct task_smack *tsp; struct smack_known *tracer_known; if ((mode & PTRACE_MODE_NOAUDIT) == 0) { smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, tracer); saip = &ad; } tsp = task_security(tracer); tracer_known = smk_of_task(tsp); if ((mode & PTRACE_MODE_ATTACH) && (smack_ptrace_rule == SMACK_PTRACE_EXACT || smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) { if (tracer_known->smk_known == tracee_known->smk_known) rc = 0; else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN) rc = -EACCES; else if (capable(CAP_SYS_PTRACE)) rc = 0; else rc = -EACCES; if (saip) smack_log(tracer_known->smk_known, tracee_known->smk_known, 0, rc, saip); return rc; } /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */ rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip); return rc; } /* * LSM hooks. * We he, that is fun! */ /** * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH * @ctp: child task pointer * @mode: ptrace attachment mode (PTRACE_MODE_*) * * Returns 0 if access is OK, an error code otherwise * * Do the capability checks. */ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) { int rc; struct smack_known *skp; rc = cap_ptrace_access_check(ctp, mode); if (rc != 0) return rc; skp = smk_of_task(task_security(ctp)); rc = smk_ptrace_rule_check(current, skp, mode, __func__); 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 PTRACE_MODE_ATTACH. */ static int smack_ptrace_traceme(struct task_struct *ptp) { int rc; struct smack_known *skp; rc = cap_ptrace_traceme(ptp); if (rc != 0) return rc; skp = smk_of_task(current_security()); rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__); return rc; } /** * smack_syslog - Smack approval on syslog * @type: message type * * Returns 0 on success, error code otherwise. */ static int smack_syslog(int typefrom_file) { int rc = 0; struct smack_known *skp = smk_of_current(); if (smack_privileged(CAP_MAC_OVERRIDE)) return 0; if (smack_syslog_label != NULL && smack_syslog_label != skp) 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; sbsp->smk_default = &smack_known_floor; sbsp->smk_floor = &smack_known_floor; sbsp->smk_hat = &smack_known_hat; /* * smk_initialized will be zero from kzalloc. */ 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 * @orig: where to start * @smackopts: mount options string * * 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 if (strstr(cp, SMK_FSTRANS) == 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; struct smack_known *skp; char *op; char *commap; int transmute = 0; int specified = 0; if (sp->smk_initialized) return 0; sp->smk_initialized = 1; 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); skp = smk_import_entry(op, 0); if (skp != NULL) { sp->smk_hat = skp; specified = 1; } } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) { op += strlen(SMK_FSFLOOR); skp = smk_import_entry(op, 0); if (skp != NULL) { sp->smk_floor = skp; specified = 1; } } else if (strncmp(op, SMK_FSDEFAULT, strlen(SMK_FSDEFAULT)) == 0) { op += strlen(SMK_FSDEFAULT); skp = smk_import_entry(op, 0); if (skp != NULL) { sp->smk_default = skp; specified = 1; } } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) { op += strlen(SMK_FSROOT); skp = smk_import_entry(op, 0); if (skp != NULL) { sp->smk_root = skp; specified = 1; } } else if (strncmp(op, SMK_FSTRANS, strlen(SMK_FSTRANS)) == 0) { op += strlen(SMK_FSTRANS); skp = smk_import_entry(op, 0); if (skp != NULL) { sp->smk_root = skp; transmute = 1; specified = 1; } } } if (!smack_privileged(CAP_MAC_ADMIN)) { /* * Unprivileged mounts don't get to specify Smack values. */ if (specified) return -EPERM; /* * Unprivileged mounts get root and default from the caller. */ skp = smk_of_current(); sp->smk_root = skp; sp->smk_default = skp; } /* * Initialize the root inode. */ isp = inode->i_security; if (isp == NULL) { isp = new_inode_smack(sp->smk_root); if (isp == NULL) return -ENOMEM; inode->i_security = isp; } else isp->smk_inode = sp->smk_root; if (transmute) isp->smk_flags |= SMK_INODE_TRANSMUTE; 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; int rc; struct smk_audit_info ad; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc); return rc; } /* * BPRM hooks */ /** * smack_bprm_set_creds - set creds for exec * @bprm: the exec information * * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise */ static int smack_bprm_set_creds(struct linux_binprm *bprm) { struct inode *inode = file_inode(bprm->file); struct task_smack *bsp = bprm->cred->security; struct inode_smack *isp; int rc; rc = cap_bprm_set_creds(bprm); if (rc != 0) return rc; if (bprm->cred_prepared) return 0; isp = inode->i_security; if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task) return 0; if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { struct task_struct *tracer; rc = 0; rcu_read_lock(); tracer = ptrace_parent(current); if (likely(tracer != NULL)) rc = smk_ptrace_rule_check(tracer, isp->smk_task, PTRACE_MODE_ATTACH, __func__); rcu_read_unlock(); if (rc != 0) return rc; } else if (bprm->unsafe) return -EPERM; bsp->smk_task = isp->smk_task; bprm->per_clear |= PER_CLEAR_ON_SETID; return 0; } /** * smack_bprm_committing_creds - Prepare to install the new credentials * from bprm. * * @bprm: binprm for exec */ static void smack_bprm_committing_creds(struct linux_binprm *bprm) { struct task_smack *bsp = bprm->cred->security; if (bsp->smk_task != bsp->smk_forked) current->pdeath_signal = 0; } /** * smack_bprm_secureexec - Return the decision to use secureexec. * @bprm: binprm for exec * * Returns 0 on success. */ static int smack_bprm_secureexec(struct linux_binprm *bprm) { struct task_smack *tsp = current_security(); int ret = cap_bprm_secureexec(bprm); if (!ret && (tsp->smk_task != tsp->smk_forked)) ret = 1; return ret; } /* * 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) { struct smack_known *skp = smk_of_current(); inode->i_security = new_inode_smack(skp); 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) { kmem_cache_free(smack_inode_cache, inode->i_security); inode->i_security = NULL; } /** * smack_inode_init_security - copy out the smack from an inode * @inode: the newly created inode * @dir: containing directory object * @qstr: 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, const struct qstr *qstr, const char **name, void **value, size_t *len) { struct inode_smack *issp = inode->i_security; struct smack_known *skp = smk_of_current(); struct smack_known *isp = smk_of_inode(inode); struct smack_known *dsp = smk_of_inode(dir); int may; if (name) *name = XATTR_SMACK_SUFFIX; if (value && len) { rcu_read_lock(); may = smk_access_entry(skp->smk_known, dsp->smk_known, &skp->smk_rules); rcu_read_unlock(); /* * If the access rule allows transmutation and * the directory requests transmutation then * by all means transmute. * Mark the inode as changed. */ if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && smk_inode_transmutable(dir)) { isp = dsp; issp->smk_flags |= SMK_INODE_CHANGED; } *value = kstrdup(isp->smk_known, GFP_NOFS); if (*value == NULL) return -ENOMEM; *len = strlen(isp->smk_known); } 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) { struct smack_known *isp; struct smk_audit_info ad; int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); rc = smk_curacc(isp, MAY_WRITE, &ad); rc = smk_bu_inode(old_dentry->d_inode, MAY_WRITE, rc); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); rc = smk_curacc(isp, MAY_WRITE, &ad); rc = smk_bu_inode(new_dentry->d_inode, MAY_WRITE, rc); } 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; struct smk_audit_info ad; int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); /* * You need write access to the thing you're unlinking */ rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); rc = smk_bu_inode(ip, MAY_WRITE, rc); if (rc == 0) { /* * You also need write access to the containing directory */ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); smk_ad_setfield_u_fs_inode(&ad, dir); rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); rc = smk_bu_inode(dir, MAY_WRITE, rc); } 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) { struct smk_audit_info ad; int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); /* * You need write access to the thing you're removing */ rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc); if (rc == 0) { /* * You also need write access to the containing directory */ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); smk_ad_setfield_u_fs_inode(&ad, dir); rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); rc = smk_bu_inode(dir, MAY_WRITE, rc); } return rc; } /** * smack_inode_rename - Smack check on rename * @old_inode: unused * @old_dentry: the old object * @new_inode: unused * @new_dentry: the new object * * 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; struct smack_known *isp; struct smk_audit_info ad; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); rc = smk_curacc(isp, MAY_READWRITE, &ad); rc = smk_bu_inode(old_dentry->d_inode, MAY_READWRITE, rc); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); rc = smk_curacc(isp, MAY_READWRITE, &ad); rc = smk_bu_inode(new_dentry->d_inode, MAY_READWRITE, rc); } return rc; } /** * smack_inode_permission - Smack version of permission() * @inode: the inode in question * @mask: the access requested * * This is the important Smack hook. * * Returns 0 if access is permitted, -EACCES otherwise */ static int smack_inode_permission(struct inode *inode, int mask) { struct smk_audit_info ad; int no_block = mask & MAY_NOT_BLOCK; int rc; mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); /* * No permission to check. Existence test. Yup, it's there. */ if (mask == 0) return 0; /* May be droppable after audit */ if (no_block) return -ECHILD; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); smk_ad_setfield_u_fs_inode(&ad, inode); rc = smk_curacc(smk_of_inode(inode), mask, &ad); rc = smk_bu_inode(inode, mask, rc); return rc; } /** * 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) { struct smk_audit_info ad; int rc; /* * Need to allow for clearing the setuid bit. */ if (iattr->ia_valid & ATTR_FORCE) return 0; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc); return rc; } /** * smack_inode_getattr - Smack check for getting attributes * @mnt: vfsmount of the object * @dentry: the object * * Returns 0 if access is permitted, an error code otherwise */ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { struct smk_audit_info ad; struct path path; int rc; path.dentry = dentry; path.mnt = mnt; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, path); rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc); return rc; } /** * smack_inode_setxattr - Smack check for setting xattrs * @dentry: the object * @name: name of the attribute * @value: value of the attribute * @size: size of the value * @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) { struct smk_audit_info ad; struct smack_known *skp; int check_priv = 0; int check_import = 0; int check_star = 0; int rc = 0; /* * Check label validity here so import won't fail in post_setxattr */ if (strcmp(name, XATTR_NAME_SMACK) == 0 || strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { check_priv = 1; check_import = 1; } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { check_priv = 1; check_import = 1; check_star = 1; } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { check_priv = 1; if (size != TRANS_TRUE_SIZE || strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0) rc = -EINVAL; } else rc = cap_inode_setxattr(dentry, name, value, size, flags); if (check_priv && !smack_privileged(CAP_MAC_ADMIN)) rc = -EPERM; if (rc == 0 && check_import) { skp = size ? smk_import_entry(value, size) : NULL; if (skp == NULL || (check_star && (skp == &smack_known_star || skp == &smack_known_web))) rc = -EINVAL; } smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); if (rc == 0) { rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc); } 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 smack_known *skp; struct inode_smack *isp = dentry->d_inode->i_security; if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { isp->smk_flags |= SMK_INODE_TRANSMUTE; return; } if (strcmp(name, XATTR_NAME_SMACK) == 0) { skp = smk_import_entry(value, size); if (skp != NULL) isp->smk_inode = skp; else isp->smk_inode = &smack_known_invalid; } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) { skp = smk_import_entry(value, size); if (skp != NULL) isp->smk_task = skp; else isp->smk_task = &smack_known_invalid; } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { skp = smk_import_entry(value, size); if (skp != NULL) isp->smk_mmap = skp; else isp->smk_mmap = &smack_known_invalid; } 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) { struct smk_audit_info ad; int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_READ, rc); return rc; } /** * 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) { struct inode_smack *isp; struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 || strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { if (!smack_privileged(CAP_MAC_ADMIN)) rc = -EPERM; } else rc = cap_inode_removexattr(dentry, name); if (rc != 0) return rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); smk_ad_setfield_u_fs_path_dentry(&ad, dentry); rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); rc = smk_bu_inode(dentry->d_inode, MAY_WRITE, rc); if (rc != 0) return rc; isp = dentry->d_inode->i_security; /* * Don't do anything special for these. * XATTR_NAME_SMACKIPIN * XATTR_NAME_SMACKIPOUT * XATTR_NAME_SMACKEXEC */ if (strcmp(name, XATTR_NAME_SMACK) == 0) isp->smk_task = NULL; else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) isp->smk_mmap = NULL; else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) isp->smk_flags &= ~SMK_INODE_TRANSMUTE; return 0; } /** * smack_inode_getsecurity - get smack xattrs * @inode: the object * @name: attribute name * @buffer: where to put the result * @alloc: 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; struct smack_known *isp; int ilen; int rc = 0; if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { isp = smk_of_inode(inode); ilen = strlen(isp->smk_known); *buffer = isp->smk_known; 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->smk_known); if (rc == 0) { *buffer = isp->smk_known; 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 = sizeof(XATTR_NAME_SMACK); if (buffer != NULL && len <= buffer_size) memcpy(buffer, XATTR_NAME_SMACK, len); return len; } /** * 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 = isp->smk_inode->smk_secid; } /* * 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) { struct smack_known *skp = smk_of_current(); file->f_security = skp; 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; struct smk_audit_info ad; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); if (_IOC_DIR(cmd) & _IOC_WRITE) { rc = smk_curacc(file->f_security, MAY_WRITE, &ad); rc = smk_bu_file(file, MAY_WRITE, rc); } if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) { rc = smk_curacc(file->f_security, MAY_READ, &ad); rc = smk_bu_file(file, MAY_READ, rc); } return rc; } /** * smack_file_lock - Smack check on file locking * @file: the object * @cmd: unused * * Returns 0 if current has lock access, error code otherwise */ static int smack_file_lock(struct file *file, unsigned int cmd) { struct smk_audit_info ad; int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); rc = smk_curacc(file->f_security, MAY_LOCK, &ad); rc = smk_bu_file(file, MAY_LOCK, rc); return rc; } /** * smack_file_fcntl - Smack check on fcntl * @file: the object * @cmd: what action to check * @arg: unused * * Generally these operations are harmless. * File locking operations present an obvious mechanism * for passing information, so they require write access. * * Returns 0 if current has access, error code otherwise */ static int smack_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { struct smk_audit_info ad; int rc = 0; switch (cmd) { case F_GETLK: break; case F_SETLK: case F_SETLKW: smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); rc = smk_curacc(file->f_security, MAY_LOCK, &ad); rc = smk_bu_file(file, MAY_LOCK, rc); break; case F_SETOWN: case F_SETSIG: smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); rc = smk_curacc(file->f_security, MAY_WRITE, &ad); rc = smk_bu_file(file, MAY_WRITE, rc); break; default: break; } return rc; } /** * smack_mmap_file : * Check permissions for a mmap operation. The @file may be NULL, e.g. * if mapping anonymous memory. * @file contains the file structure for file to map (may be NULL). * @reqprot contains the protection requested by the application. * @prot contains the protection that will be applied by the kernel. * @flags contains the operational flags. * Return 0 if permission is granted. */ static int smack_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, unsigned long flags) { struct smack_known *skp; struct smack_known *mkp; struct smack_rule *srp; struct task_smack *tsp; struct smack_known *okp; struct inode_smack *isp; int may; int mmay; int tmay; int rc; if (file == NULL) return 0; isp = file_inode(file)->i_security; if (isp->smk_mmap == NULL) return 0; mkp = isp->smk_mmap; tsp = current_security(); skp = smk_of_current(); rc = 0; rcu_read_lock(); /* * For each Smack rule associated with the subject * label verify that the SMACK64MMAP also has access * to that rule's object label. */ list_for_each_entry_rcu(srp, &skp->smk_rules, list) { okp = srp->smk_object; /* * Matching labels always allows access. */ if (mkp->smk_known == okp->smk_known) continue; /* * If there is a matching local rule take * that into account as well. */ may = smk_access_entry(srp->smk_subject->smk_known, okp->smk_known, &tsp->smk_rules); if (may == -ENOENT) may = srp->smk_access; else may &= srp->smk_access; /* * If may is zero the SMACK64MMAP subject can't * possibly have less access. */ if (may == 0) continue; /* * Fetch the global list entry. * If there isn't one a SMACK64MMAP subject * can't have as much access as current. */ mmay = smk_access_entry(mkp->smk_known, okp->smk_known, &mkp->smk_rules); if (mmay == -ENOENT) { rc = -EACCES; break; } /* * If there is a local entry it modifies the * potential access, too. */ tmay = smk_access_entry(mkp->smk_known, okp->smk_known, &tsp->smk_rules); if (tmay != -ENOENT) mmay &= tmay; /* * If there is any access available to current that is * not available to a SMACK64MMAP subject * deny access. */ if ((may | mmay) != mmay) { rc = -EACCES; break; } } rcu_read_unlock(); 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 void smack_file_set_fowner(struct file *file) { struct smack_known *skp = smk_of_current(); file->f_security = skp; } /** * 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 smack_known *skp; struct smack_known *tkp = smk_of_task(tsk->cred->security); struct file *file; int rc; struct smk_audit_info ad; /* * struct fown_struct is never outside the context of a struct file */ file = container_of(fown, struct file, f_owner); /* we don't log here as rc can be overriden */ skp = file->f_security; rc = smk_access(skp, tkp, MAY_WRITE, NULL); rc = smk_bu_note("sigiotask", skp, tkp, MAY_WRITE, rc); if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) rc = 0; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, tsk); smack_log(skp->smk_known, tkp->smk_known, MAY_WRITE, rc, &ad); 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 rc; int may = 0; struct smk_audit_info ad; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); /* * This code relies on bitmasks. */ if (file->f_mode & FMODE_READ) may = MAY_READ; if (file->f_mode & FMODE_WRITE) may |= MAY_WRITE; rc = smk_curacc(file->f_security, may, &ad); rc = smk_bu_file(file, may, rc); return rc; } /** * smack_file_open - Smack dentry open processing * @file: the object * @cred: task credential * * Set the security blob in the file structure. * Allow the open only if the task has read access. There are * many read operations (e.g. fstat) that you can do with an * fd even if you have the file open write-only. * * Returns 0 */ static int smack_file_open(struct file *file, const struct cred *cred) { struct task_smack *tsp = cred->security; struct inode_smack *isp = file_inode(file)->i_security; struct smk_audit_info ad; int rc; if (smack_privileged(CAP_MAC_OVERRIDE)) { file->f_security = isp->smk_inode; return 0; } smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); smk_ad_setfield_u_fs_path(&ad, file->f_path); rc = smk_access(tsp->smk_task, isp->smk_inode, MAY_READ, &ad); rc = smk_bu_credfile(cred, file, MAY_READ, rc); if (rc == 0) file->f_security = isp->smk_inode; return rc; } /* * Task hooks */ /** * smack_cred_alloc_blank - "allocate" blank task-level security credentials * @new: the new credentials * @gfp: the atomicity of any memory allocations * * Prepare a blank set of credentials for modification. This must allocate all * the memory the LSM module might require such that cred_transfer() can * complete without error. */ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) { struct task_smack *tsp; tsp = new_task_smack(NULL, NULL, gfp); if (tsp == NULL) return -ENOMEM; cred->security = tsp; return 0; } /** * smack_cred_free - "free" task-level security credentials * @cred: the credentials in question * */ static void smack_cred_free(struct cred *cred) { struct task_smack *tsp = cred->security; struct smack_rule *rp; struct list_head *l; struct list_head *n; if (tsp == NULL) return; cred->security = NULL; list_for_each_safe(l, n, &tsp->smk_rules) { rp = list_entry(l, struct smack_rule, list); list_del(&rp->list); kfree(rp); } kfree(tsp); } /** * 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) { struct task_smack *old_tsp = old->security; struct task_smack *new_tsp; int rc; new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp); if (new_tsp == NULL) return -ENOMEM; rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp); if (rc != 0) return rc; new->security = new_tsp; return 0; } /** * smack_cred_transfer - Transfer the old credentials to the new credentials * @new: the new credentials * @old: the original credentials * * Fill in a set of blank credentials from another set of credentials. */ static void smack_cred_transfer(struct cred *new, const struct cred *old) { struct task_smack *old_tsp = old->security; struct task_smack *new_tsp = new->security; new_tsp->smk_task = old_tsp->smk_task; new_tsp->smk_forked = old_tsp->smk_task; mutex_init(&new_tsp->smk_rules_lock); INIT_LIST_HEAD(&new_tsp->smk_rules); /* cbs copy rule list */ } /** * 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) { struct task_smack *new_tsp = new->security; struct smack_known *skp = smack_from_secid(secid); if (skp == NULL) return -EINVAL; new_tsp->smk_task = skp; 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; struct task_smack *tsp = new->security; tsp->smk_forked = isp->smk_inode; tsp->smk_task = tsp->smk_forked; return 0; } /** * smk_curacc_on_task - helper to log task related access * @p: the task object * @access: the access requested * @caller: name of the calling function for audit * * Return 0 if access is permitted */ static int smk_curacc_on_task(struct task_struct *p, int access, const char *caller) { struct smk_audit_info ad; struct smack_known *skp = smk_of_task(task_security(p)); int rc; smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, p); rc = smk_curacc(skp, access, &ad); rc = smk_bu_task(p, access, rc); return rc; } /** * 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_on_task(p, MAY_WRITE, __func__); } /** * 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_on_task(p, MAY_READ, __func__); } /** * 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_on_task(p, MAY_READ, __func__); } /** * 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) { struct smack_known *skp = smk_of_task(task_security(p)); *secid = skp->smk_secid; } /** * 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_on_task(p, MAY_WRITE, __func__); 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_on_task(p, MAY_WRITE, __func__); 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_on_task(p, MAY_READ, __func__); } /** * 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 rc; rc = cap_task_setscheduler(p); if (rc == 0) rc = smk_curacc_on_task(p, MAY_WRITE, __func__); 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_on_task(p, MAY_READ, __func__); } /** * 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_on_task(p, MAY_WRITE, __func__); } /** * 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) { struct smk_audit_info ad; struct smack_known *skp; struct smack_known *tkp = smk_of_task(task_security(p)); int rc; smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, p); /* * Sending a signal requires that the sender * can write the receiver. */ if (secid == 0) { rc = smk_curacc(tkp, MAY_WRITE, &ad); rc = smk_bu_task(p, MAY_WRITE, rc); return rc; } /* * 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. */ skp = smack_from_secid(secid); rc = smk_access(skp, tkp, MAY_WRITE, &ad); rc = smk_bu_note("USB signal", skp, tkp, MAY_WRITE, rc); return rc; } /** * smack_task_wait - Smack access check for waiting * @p: task to wait for * * Returns 0 */ static int smack_task_wait(struct task_struct *p) { /* * Allow the operation to succeed. * Zombies are bad. * In userless environments (e.g. phones) programs * get marked with SMACK64EXEC and even if the parent * and child shouldn't be talking the parent still * may expect to know when the child exits. */ return 0; } /** * 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; struct smack_known *skp = smk_of_task(task_security(p)); isp->smk_inode = skp; } /* * Socket hooks. */ /** * smack_sk_alloc_security - Allocate a socket blob * @sk: the socket * @family: unused * @gfp_flags: memory allocation flags * * 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) { struct smack_known *skp = smk_of_current(); struct socket_smack *ssp; ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); if (ssp == NULL) return -ENOMEM; ssp->smk_in = skp; ssp->smk_out = skp; ssp->smk_packet = NULL; 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_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. The caller is responsible for ensuring that the RCU read lock is * taken before calling this function. * * Returns the label of the far end or NULL if it's not special. */ static struct smack_known *smack_host_label(struct sockaddr_in *sip) { struct smk_netlbladdr *snp; struct in_addr *siap = &sip->sin_addr; if (siap->s_addr == 0) return NULL; list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) /* * we break after finding the first match because * the list is sorted from longest to shortest mask * so we have found the most specific match */ if ((&snp->smk_host.sin_addr)->s_addr == (siap->s_addr & (&snp->smk_mask)->s_addr)) { /* we have found the special CIPSO option */ if (snp->smk_label == &smack_cipso_option) return NULL; return snp->smk_label; } return NULL; } /** * 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 smack_known *skp; struct socket_smack *ssp = sk->sk_security; int rc = 0; /* * 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 { skp = ssp->smk_out; rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel); } bh_unlock_sock(sk); local_bh_enable(); return rc; } /** * smack_netlbel_send - Set the secattr on a socket and perform access checks * @sk: the socket * @sap: the destination address * * Set the correct secattr for the given socket based on the destination * address and perform any outbound access checks needed. * * Returns 0 on success or an error code. * */ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) { struct smack_known *skp; int rc; int sk_lbl; struct smack_known *hkp; struct socket_smack *ssp = sk->sk_security; struct smk_audit_info ad; rcu_read_lock(); hkp = smack_host_label(sap); if (hkp != NULL) { #ifdef CONFIG_AUDIT struct lsm_network_audit net; smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); ad.a.u.net->family = sap->sin_family; ad.a.u.net->dport = sap->sin_port; ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr; #endif sk_lbl = SMACK_UNLABELED_SOCKET; skp = ssp->smk_out; rc = smk_access(skp, hkp, MAY_WRITE, &ad); rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc); } else { sk_lbl = SMACK_CIPSO_SOCKET; rc = 0; } rcu_read_unlock(); if (rc != 0) return rc; return smack_netlabel(sk, sk_lbl); } /** * smk_ipv6_port_label - Smack port access table management * @sock: socket * @address: address * * Create or update the port list entry */ static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address) { struct sock *sk = sock->sk; struct sockaddr_in6 *addr6; struct socket_smack *ssp = sock->sk->sk_security; struct smk_port_label *spp; unsigned short port = 0; if (address == NULL) { /* * This operation is changing the Smack information * on the bound socket. Take the changes to the port * as well. */ list_for_each_entry(spp, &smk_ipv6_port_list, list) { if (sk != spp->smk_sock) continue; spp->smk_in = ssp->smk_in; spp->smk_out = ssp->smk_out; return; } /* * A NULL address is only used for updating existing * bound entries. If there isn't one, it's OK. */ return; } addr6 = (struct sockaddr_in6 *)address; port = ntohs(addr6->sin6_port); /* * This is a special case that is safely ignored. */ if (port == 0) return; /* * Look for an existing port list entry. * This is an indication that a port is getting reused. */ list_for_each_entry(spp, &smk_ipv6_port_list, list) { if (spp->smk_port != port) continue; spp->smk_port = port; spp->smk_sock = sk; spp->smk_in = ssp->smk_in; spp->smk_out = ssp->smk_out; return; } /* * A new port entry is required. */ spp = kzalloc(sizeof(*spp), GFP_KERNEL); if (spp == NULL) return; spp->smk_port = port; spp->smk_sock = sk; spp->smk_in = ssp->smk_in; spp->smk_out = ssp->smk_out; list_add(&spp->list, &smk_ipv6_port_list); return; } /** * smk_ipv6_port_check - check Smack port access * @sock: socket * @address: address * * Create or update the port list entry */ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address, int act) { __be16 *bep; __be32 *be32p; struct smk_port_label *spp; struct socket_smack *ssp = sk->sk_security; struct smack_known *skp; unsigned short port = 0; struct smack_known *object; struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT struct lsm_network_audit net; #endif if (act == SMK_RECEIVING) { skp = smack_net_ambient; object = ssp->smk_in; } else { skp = ssp->smk_out; object = smack_net_ambient; } /* * Get the IP address and port from the address. */ port = ntohs(address->sin6_port); bep = (__be16 *)(&address->sin6_addr); be32p = (__be32 *)(&address->sin6_addr); /* * It's remote, so port lookup does no good. */ if (be32p[0] || be32p[1] || be32p[2] || bep[6] || ntohs(bep[7]) != 1) goto auditout; /* * It's local so the send check has to have passed. */ if (act == SMK_RECEIVING) { skp = &smack_known_web; goto auditout; } list_for_each_entry(spp, &smk_ipv6_port_list, list) { if (spp->smk_port != port) continue; object = spp->smk_in; if (act == SMK_CONNECTING) ssp->smk_packet = spp->smk_out; break; } auditout: #ifdef CONFIG_AUDIT smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); ad.a.u.net->family = sk->sk_family; ad.a.u.net->dport = port; if (act == SMK_RECEIVING) ad.a.u.net->v6info.saddr = address->sin6_addr; else ad.a.u.net->v6info.daddr = address->sin6_addr; #endif rc = smk_access(skp, object, MAY_WRITE, &ad); rc = smk_bu_note("IPv6 port check", skp, object, MAY_WRITE, rc); 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) { struct smack_known *skp; struct inode_smack *nsp = inode->i_security; struct socket_smack *ssp; struct socket *sock; int rc = 0; if (value == NULL || size > SMK_LONGLABEL || size == 0) return -EINVAL; skp = smk_import_entry(value, size); if (skp == NULL) return -EINVAL; if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { nsp->smk_inode = skp; nsp->smk_flags |= SMK_INODE_INSTANT; 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 = skp; else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { ssp->smk_out = skp; if (sock->sk->sk_family == PF_INET) { 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; if (sock->sk->sk_family == PF_INET6) smk_ipv6_port_label(sock, NULL); 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_socket_bind - record port binding information. * @sock: the socket * @address: the port address * @addrlen: size of the address * * Records the label bound to a port. * * Returns 0 */ static int smack_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) { if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) smk_ipv6_port_label(sock, address); return 0; } /** * 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) { int rc = 0; if (sock->sk == NULL) return 0; switch (sock->sk->sk_family) { case PF_INET: if (addrlen < sizeof(struct sockaddr_in)) return -EINVAL; rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap); break; case PF_INET6: if (addrlen < sizeof(struct sockaddr_in6)) return -EINVAL; rc = smk_ipv6_port_check(sock->sk, (struct sockaddr_in6 *)sap, SMK_CONNECTING); break; } return rc; } /** * 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) { struct smack_known *skp = smk_of_current(); msg->security = skp; 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 struct smack_known *smack_of_shm(struct shmid_kernel *shp) { return (struct smack_known *)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; struct smack_known *skp = smk_of_current(); isp->security = skp; 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; } /** * smk_curacc_shm : check if current has access on shm * @shp : the object * @access : access requested * * Returns 0 if current has the requested access, error code otherwise */ static int smk_curacc_shm(struct shmid_kernel *shp, int access) { struct smack_known *ssp = smack_of_shm(shp); struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); ad.a.u.ipc_id = shp->shm_perm.id; #endif rc = smk_curacc(ssp, access, &ad); rc = smk_bu_current("shm", ssp, access, rc); return rc; } /** * 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) { int may; may = smack_flags_to_may(shmflg); return smk_curacc_shm(shp, 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) { 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; } return smk_curacc_shm(shp, 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) { int may; may = smack_flags_to_may(shmflg); return smk_curacc_shm(shp, may); } /** * smack_of_sem - the smack pointer for the sem * @sma: the object * * Returns a pointer to the smack value */ static struct smack_known *smack_of_sem(struct sem_array *sma) { return (struct smack_known *)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; struct smack_known *skp = smk_of_current(); isp->security = skp; 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; } /** * smk_curacc_sem : check if current has access on sem * @sma : the object * @access : access requested * * Returns 0 if current has the requested access, error code otherwise */ static int smk_curacc_sem(struct sem_array *sma, int access) { struct smack_known *ssp = smack_of_sem(sma); struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); ad.a.u.ipc_id = sma->sem_perm.id; #endif rc = smk_curacc(ssp, access, &ad); rc = smk_bu_current("sem", ssp, access, rc); return rc; } /** * 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) { int may; may = smack_flags_to_may(semflg); return smk_curacc_sem(sma, 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) { 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; } return smk_curacc_sem(sma, 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) { return smk_curacc_sem(sma, 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; struct smack_known *skp = smk_of_current(); kisp->security = skp; 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 label entry */ static struct smack_known *smack_of_msq(struct msg_queue *msq) { return (struct smack_known *)msq->q_perm.security; } /** * smk_curacc_msq : helper to check if current has access on msq * @msq : the msq * @access : access requested * * return 0 if current has access, error otherwise */ static int smk_curacc_msq(struct msg_queue *msq, int access) { struct smack_known *msp = smack_of_msq(msq); struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); ad.a.u.ipc_id = msq->q_perm.id; #endif rc = smk_curacc(msp, access, &ad); rc = smk_bu_current("msq", msp, access, rc); return rc; } /** * 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) { int may; may = smack_flags_to_may(msqflg); return smk_curacc_msq(msq, 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) { 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; } return smk_curacc_msq(msq, 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) { int may; may = smack_flags_to_may(msqflg); return smk_curacc_msq(msq, may); } /** * 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) { return smk_curacc_msq(msq, 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) { struct smack_known *iskp = ipp->security; int may = smack_flags_to_may(flag); struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); ad.a.u.ipc_id = ipp->id; #endif rc = smk_curacc(iskp, may, &ad); rc = smk_bu_current("svipc", iskp, may, rc); return rc; } /** * smack_ipc_getsecid - Extract smack security id * @ipp: the object permissions * @secid: where result will be saved */ static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) { struct smack_known *iskp = ipp->security; *secid = iskp->smk_secid; } /** * smack_d_instantiate - Make sure the blob is correct on an inode * @opt_dentry: dentry where inode will be attached * @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; struct smack_known *skp; struct smack_known *ckp = smk_of_current(); struct smack_known *final; char trattr[TRANS_TRUE_SIZE]; int transflag = 0; int rc; 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) { if (sbp->s_magic == CGROUP_SUPER_MAGIC) { /* * The cgroup filesystem is never mounted, * so there's no opportunity to set the mount * options. */ sbsp->smk_root = &smack_known_star; sbsp->smk_default = &smack_known_star; } 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: case PIPEFS_MAGIC: case SOCKFS_MAGIC: case CGROUP_SUPER_MAGIC: /* * Casey says that it's a little embarrassing * that the smack file system doesn't do * extended attributes. * * Casey says pipes are easy (?) * * Socket access is controlled by the socket * structures associated with the task involved. * * Cgroupfs is special */ final = &smack_known_star; 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 = ckp; 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; /* * 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. */ /* * UNIX domain sockets use lower level socket data. */ if (S_ISSOCK(inode->i_mode)) { final = &smack_known_star; break; } /* * 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. */ dp = dget(opt_dentry); skp = smk_fetch(XATTR_NAME_SMACK, inode, dp); if (skp != NULL) final = skp; /* * Transmuting directory */ if (S_ISDIR(inode->i_mode)) { /* * If this is a new directory and the label was * transmuted when the inode was initialized * set the transmute attribute on the directory * and mark the inode. * * If there is a transmute attribute on the * directory mark the inode. */ if (isp->smk_flags & SMK_INODE_CHANGED) { isp->smk_flags &= ~SMK_INODE_CHANGED; rc = inode->i_op->setxattr(dp, XATTR_NAME_SMACKTRANSMUTE, TRANS_TRUE, TRANS_TRUE_SIZE, 0); } else { rc = inode->i_op->getxattr(dp, XATTR_NAME_SMACKTRANSMUTE, trattr, TRANS_TRUE_SIZE); if (rc >= 0 && strncmp(trattr, TRANS_TRUE, TRANS_TRUE_SIZE) != 0) rc = -EINVAL; } if (rc >= 0) transflag = SMK_INODE_TRANSMUTE; } /* * Don't let the exec or mmap label be "*" or "@". */ skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); if (skp == &smack_known_star || skp == &smack_known_web) skp = NULL; isp->smk_task = skp; skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); if (skp == &smack_known_star || skp == &smack_known_web) skp = NULL; isp->smk_mmap = skp; dput(dp); break; } if (final == NULL) isp->smk_inode = ckp; else isp->smk_inode = final; isp->smk_flags |= (SMK_INODE_INSTANT | transflag); 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) { struct smack_known *skp = smk_of_task(task_security(p)); char *cp; int slen; if (strcmp(name, "current") != 0) return -EINVAL; cp = kstrdup(skp->smk_known, 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 task_smack *tsp; struct cred *new; struct smack_known *skp; /* * Changing another process' Smack value is too dangerous * and supports no sane use case. */ if (p != current) return -EPERM; if (!smack_privileged(CAP_MAC_ADMIN)) return -EPERM; if (value == NULL || size == 0 || size >= SMK_LONGLABEL) return -EINVAL; if (strcmp(name, "current") != 0) return -EINVAL; skp = smk_import_entry(value, size); if (skp == NULL) return -EINVAL; /* * No process is ever allowed the web ("@") label. */ if (skp == &smack_known_web) return -EPERM; new = prepare_creds(); if (new == NULL) return -ENOMEM; tsp = new->security; tsp->smk_task = skp; commit_creds(new); return size; } /** * smack_unix_stream_connect - Smack access on UDS * @sock: one sock * @other: the other sock * @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 sock *sock, struct sock *other, struct sock *newsk) { struct smack_known *skp; struct smack_known *okp; struct socket_smack *ssp = sock->sk_security; struct socket_smack *osp = other->sk_security; struct socket_smack *nsp = newsk->sk_security; struct smk_audit_info ad; int rc = 0; #ifdef CONFIG_AUDIT struct lsm_network_audit net; #endif if (!smack_privileged(CAP_MAC_OVERRIDE)) { skp = ssp->smk_out; okp = osp->smk_out; #ifdef CONFIG_AUDIT smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); smk_ad_setfield_u_net_sk(&ad, other); #endif rc = smk_access(skp, okp, MAY_WRITE, &ad); rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc); if (rc == 0) { rc = smk_access(okp, skp, MAY_WRITE, NULL); rc = smk_bu_note("UDS connect", okp, skp, MAY_WRITE, rc); } } /* * Cross reference the peer labels for SO_PEERSEC. */ if (rc == 0) { nsp->smk_packet = ssp->smk_out; ssp->smk_packet = osp->smk_out; } return rc; } /** * 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 socket_smack *ssp = sock->sk->sk_security; struct socket_smack *osp = other->sk->sk_security; struct smk_audit_info ad; int rc; #ifdef CONFIG_AUDIT struct lsm_network_audit net; smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); smk_ad_setfield_u_net_sk(&ad, other->sk); #endif if (smack_privileged(CAP_MAC_OVERRIDE)) return 0; rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad); rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc); return rc; } /** * smack_socket_sendmsg - Smack check based on destination host * @sock: the socket * @msg: the message * @size: the size of the message * * Return 0 if the current subject can write to the destination host. * For IPv4 this is only a question if the destination is a single label host. * For IPv6 this is a check against the label of the port. */ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) { struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name; int rc = 0; /* * Perfectly reasonable for this to be NULL */ if (sip == NULL) return 0; switch (sip->sin_family) { case AF_INET: rc = smack_netlabel_send(sock->sk, sip); break; case AF_INET6: rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING); break; } return rc; } /** * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack * @sap: netlabel secattr * @ssp: socket security information * * Returns a pointer to a Smack label entry found on the label list. */ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap, struct socket_smack *ssp) { struct smack_known *skp; int found = 0; int acat; int kcat; 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. * * Look it up in the label table * Without guidance regarding the smack value * for the packet fall back on the network * ambient value. */ rcu_read_lock(); list_for_each_entry(skp, &smack_known_list, list) { if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl) continue; /* * Compare the catsets. Use the netlbl APIs. */ if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) { if ((skp->smk_netlabel.flags & NETLBL_SECATTR_MLS_CAT) == 0) found = 1; break; } for (acat = -1, kcat = -1; acat == kcat; ) { acat = netlbl_catmap_walk(sap->attr.mls.cat, acat + 1); kcat = netlbl_catmap_walk( skp->smk_netlabel.attr.mls.cat, kcat + 1); if (acat < 0 || kcat < 0) break; } if (acat == kcat) { found = 1; break; } } rcu_read_unlock(); if (found) return skp; if (ssp != NULL && ssp->smk_in == &smack_known_star) return &smack_known_web; return &smack_known_star; } if ((sap->flags & NETLBL_SECATTR_SECID) != 0) { /* * Looks like a fallback, which gives us a secid. */ skp = 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(skp == NULL); return skp; } /* * Without guidance regarding the smack value * for the packet fall back on the network * ambient value. */ return smack_net_ambient; } static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip) { u8 nexthdr; int offset; int proto = -EINVAL; struct ipv6hdr _ipv6h; struct ipv6hdr *ip6; __be16 frag_off; struct tcphdr _tcph, *th; struct udphdr _udph, *uh; struct dccp_hdr _dccph, *dh; sip->sin6_port = 0; offset = skb_network_offset(skb); ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); if (ip6 == NULL) return -EINVAL; sip->sin6_addr = ip6->saddr; nexthdr = ip6->nexthdr; offset += sizeof(_ipv6h); offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); if (offset < 0) return -EINVAL; proto = nexthdr; switch (proto) { case IPPROTO_TCP: th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); if (th != NULL) sip->sin6_port = th->source; break; case IPPROTO_UDP: uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); if (uh != NULL) sip->sin6_port = uh->source; break; case IPPROTO_DCCP: dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); if (dh != NULL) sip->sin6_port = dh->dccph_sport; break; } return proto; } /** * 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; struct smack_known *skp; struct sockaddr_in6 sadd; int rc = 0; struct smk_audit_info ad; #ifdef CONFIG_AUDIT struct lsm_network_audit net; #endif switch (sk->sk_family) { case PF_INET: /* * Translate what netlabel gave us. */ netlbl_secattr_init(&secattr); rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); if (rc == 0) skp = smack_from_secattr(&secattr, ssp); else skp = smack_net_ambient; netlbl_secattr_destroy(&secattr); #ifdef CONFIG_AUDIT smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); ad.a.u.net->family = sk->sk_family; ad.a.u.net->netif = skb->skb_iif; ipv4_skb_to_auditdata(skb, &ad.a, NULL); #endif /* * 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(skp, ssp->smk_in, MAY_WRITE, &ad); rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in, MAY_WRITE, rc); if (rc != 0) netlbl_skbuff_err(skb, rc, 0); break; case PF_INET6: rc = smk_skb_to_addr_ipv6(skb, &sadd); if (rc == IPPROTO_UDP || rc == IPPROTO_TCP) rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING); else rc = 0; break; } return rc; } /** * smack_socket_getpeersec_stream - pull in packet label * @sock: the socket * @optval: user's destination * @optlen: size thereof * @len: max thereof * * 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; char *rcp = ""; int slen = 1; int rc = 0; ssp = sock->sk->sk_security; if (ssp->smk_packet != NULL) { rcp = ssp->smk_packet->smk_known; slen = strlen(rcp) + 1; } if (slen > len) rc = -ERANGE; else if (copy_to_user(optval, rcp, slen) != 0) rc = -EFAULT; if (put_user(slen, optlen) != 0) rc = -EFAULT; return rc; } /** * smack_socket_getpeersec_dgram - pull in packet label * @sock: the peer 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 socket_smack *ssp = NULL; struct smack_known *skp; int family = PF_UNSPEC; u32 s = 0; /* 0 is the invalid secid */ int rc; if (skb != NULL) { if (skb->protocol == htons(ETH_P_IP)) family = PF_INET; else if (skb->protocol == htons(ETH_P_IPV6)) family = PF_INET6; } if (family == PF_UNSPEC && sock != NULL) family = sock->sk->sk_family; if (family == PF_UNIX) { ssp = sock->sk->sk_security; s = ssp->smk_out->smk_secid; } else if (family == PF_INET || family == PF_INET6) { /* * Translate what netlabel gave us. */ if (sock != NULL && sock->sk != NULL) ssp = sock->sk->sk_security; netlbl_secattr_init(&secattr); rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0) { skp = smack_from_secattr(&secattr, ssp); s = skp->smk_secid; } netlbl_secattr_destroy(&secattr); } *secid = s; if (s == 0) return -EINVAL; return 0; } /** * smack_sock_graft - Initialize a newly created socket with an existing sock * @sk: child sock * @parent: parent socket * * Set the smk_{in,out} state of an existing sock based on the process that * is creating the new socket. */ static void smack_sock_graft(struct sock *sk, struct socket *parent) { struct socket_smack *ssp; struct smack_known *skp = smk_of_current(); if (sk == NULL || (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)) return; ssp = sk->sk_security; ssp->smk_in = skp; ssp->smk_out = skp; /* cssp->smk_packet is already set in smack_inet_csk_clone() */ } /** * 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) { u16 family = sk->sk_family; struct smack_known *skp; struct socket_smack *ssp = sk->sk_security; struct netlbl_lsm_secattr secattr; struct sockaddr_in addr; struct iphdr *hdr; struct smack_known *hskp; int rc; struct smk_audit_info ad; #ifdef CONFIG_AUDIT struct lsm_network_audit net; #endif if (family == PF_INET6) { /* * Handle mapped IPv4 packets arriving * via IPv6 sockets. Don't set up netlabel * processing on IPv6. */ if (skb->protocol == htons(ETH_P_IP)) family = PF_INET; else return 0; } netlbl_secattr_init(&secattr); rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0) skp = smack_from_secattr(&secattr, ssp); else skp = &smack_known_huh; netlbl_secattr_destroy(&secattr); #ifdef CONFIG_AUDIT smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); ad.a.u.net->family = family; ad.a.u.net->netif = skb->skb_iif; ipv4_skb_to_auditdata(skb, &ad.a, NULL); #endif /* * Receiving a packet requires that the other end be able to write * here. Read access is not required. */ rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad); rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc); if (rc != 0) return rc; /* * Save the peer's label in the request_sock so we can later setup * smk_packet in the child socket so that SO_PEERCRED can report it. */ req->peer_secid = skp->smk_secid; /* * We need to decide if we want to label the incoming connection here * if we do we only need to label the request_sock and the stack will * propagate the wire-label to the sock when it is created. */ hdr = ip_hdr(skb); addr.sin_addr.s_addr = hdr->saddr; rcu_read_lock(); hskp = smack_host_label(&addr); rcu_read_unlock(); if (hskp == NULL) rc = netlbl_req_setattr(req, &skp->smk_netlabel); else netlbl_req_delattr(req); return rc; } /** * smack_inet_csk_clone - Copy the connection information to the new socket * @sk: the new socket * @req: the connection's request_sock * * Transfer the connection's peer label to the newly created socket. */ static void smack_inet_csk_clone(struct sock *sk, const struct request_sock *req) { struct socket_smack *ssp = sk->sk_security; struct smack_known *skp; if (req->peer_secid != 0) { skp = smack_from_secid(req->peer_secid); ssp->smk_packet = skp; } else ssp->smk_packet = NULL; } /* * 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) { struct smack_known *skp = smk_of_task(cred->security); key->security = skp; 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: requested key permissions * * 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, unsigned perm) { struct key *keyp; struct smk_audit_info ad; struct smack_known *tkp = smk_of_task(cred->security); int request = 0; int rc; 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 (tkp == NULL) return -EACCES; #ifdef CONFIG_AUDIT smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); ad.a.u.key_struct.key = keyp->serial; ad.a.u.key_struct.key_desc = keyp->description; #endif if (perm & KEY_NEED_READ) request = MAY_READ; if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR)) request = MAY_WRITE; rc = smk_access(tkp, keyp->security, request, &ad); rc = smk_bu_note("key access", tkp, keyp->security, request, rc); return rc; } #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) { struct smack_known *skp; 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; skp = smk_import_entry(rulestr, 0); if (skp) *rule = skp->smk_known; 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) { struct smack_known *skp; char *rule = vrule; if (unlikely(!rule)) { WARN_ONCE(1, "Smack: missing rule\n"); return -ENOENT; } if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) return 0; skp = 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 == skp->smk_known); if (op == Audit_not_equal) return (rule != skp->smk_known); 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_ismaclabel - check if xattr @name references a smack MAC label * @name: Full xattr name to check. */ static int smack_ismaclabel(const char *name) { return (strcmp(name, XATTR_SMACK_SUFFIX) == 0); } /** * 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) { struct smack_known *skp = smack_from_secid(secid); if (secdata) *secdata = skp->smk_known; *seclen = strlen(skp->smk_known); 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) { struct smack_known *skp = smk_find_entry(secdata); if (skp) *secid = skp->smk_secid; else *secid = 0; return 0; } /** * smack_release_secctx - don't do anything. * @secdata: unused * @seclen: unused * * Exists to make sure nothing gets done, and properly */ static void smack_release_secctx(char *secdata, u32 seclen) { } static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) { return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0); } static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) { return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0); } static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) { int len = 0; len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true); if (len < 0) return len; *ctxlen = len; return 0; } struct security_operations smack_ops = { .name = "smack", .ptrace_access_check = smack_ptrace_access_check, .ptrace_traceme = smack_ptrace_traceme, .syslog = smack_syslog, .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, .bprm_set_creds = smack_bprm_set_creds, .bprm_committing_creds = smack_bprm_committing_creds, .bprm_secureexec = smack_bprm_secureexec, .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_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, .mmap_file = smack_mmap_file, .mmap_addr = cap_mmap_addr, .file_set_fowner = smack_file_set_fowner, .file_send_sigiotask = smack_file_send_sigiotask, .file_receive = smack_file_receive, .file_open = smack_file_open, .cred_alloc_blank = smack_cred_alloc_blank, .cred_free = smack_cred_free, .cred_prepare = smack_cred_prepare, .cred_transfer = smack_cred_transfer, .kernel_act_as = smack_kernel_act_as, .kernel_create_files_as = smack_kernel_create_files_as, .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, .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, .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_bind = smack_socket_bind, .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, .inet_csk_clone = smack_inet_csk_clone, /* 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 */ .ismaclabel = smack_ismaclabel, .secid_to_secctx = smack_secid_to_secctx, .secctx_to_secid = smack_secctx_to_secid, .release_secctx = smack_release_secctx, .inode_notifysecctx = smack_inode_notifysecctx, .inode_setsecctx = smack_inode_setsecctx, .inode_getsecctx = smack_inode_getsecctx, }; static __init void init_smack_known_list(void) { /* * Initialize rule list locks */ mutex_init(&smack_known_huh.smk_rules_lock); mutex_init(&smack_known_hat.smk_rules_lock); mutex_init(&smack_known_floor.smk_rules_lock); mutex_init(&smack_known_star.smk_rules_lock); mutex_init(&smack_known_invalid.smk_rules_lock); mutex_init(&smack_known_web.smk_rules_lock); /* * Initialize rule lists */ INIT_LIST_HEAD(&smack_known_huh.smk_rules); INIT_LIST_HEAD(&smack_known_hat.smk_rules); INIT_LIST_HEAD(&smack_known_star.smk_rules); INIT_LIST_HEAD(&smack_known_floor.smk_rules); INIT_LIST_HEAD(&smack_known_invalid.smk_rules); INIT_LIST_HEAD(&smack_known_web.smk_rules); /* * Create the known labels list */ smk_insert_entry(&smack_known_huh); smk_insert_entry(&smack_known_hat); smk_insert_entry(&smack_known_star); smk_insert_entry(&smack_known_floor); smk_insert_entry(&smack_known_invalid); smk_insert_entry(&smack_known_web); } /** * smack_init - initialize the smack system * * Returns 0 */ static __init int smack_init(void) { struct cred *cred; struct task_smack *tsp; if (!security_module_enable(&smack_ops)) return 0; smack_inode_cache = KMEM_CACHE(inode_smack, 0); if (!smack_inode_cache) return -ENOMEM; tsp = new_task_smack(&smack_known_floor, &smack_known_floor, GFP_KERNEL); if (tsp == NULL) { kmem_cache_destroy(smack_inode_cache); return -ENOMEM; } printk(KERN_INFO "Smack: Initializing.\n"); /* * Set the security state for the initial task. */ cred = (struct cred *) current->cred; cred->security = tsp; /* initialize the smack_known_list */ init_smack_known_list(); /* * 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);