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-rw-r--r--security/smack/smack_lsm.c5105
1 files changed, 5105 insertions, 0 deletions
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
new file mode 100644
index 000000000..fbadc61fe
--- /dev/null
+++ b/security/smack/smack_lsm.c
@@ -0,0 +1,5105 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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.
+ */
+
+#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/icmpv6.h>
+#include <linux/slab.h>
+#include <linux/mutex.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 <linux/parser.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
+#include <linux/watch_queue.h>
+#include <linux/io_uring.h>
+#include "smack.h"
+
+#define TRANS_TRUE "TRUE"
+#define TRANS_TRUE_SIZE 4
+
+#define SMK_CONNECTING 0
+#define SMK_RECEIVING 1
+#define SMK_SENDING 2
+
+#ifdef SMACK_IPV6_PORT_LABELING
+static DEFINE_MUTEX(smack_ipv6_lock);
+static LIST_HEAD(smk_ipv6_port_list);
+#endif
+struct kmem_cache *smack_rule_cache;
+int smack_enabled __initdata;
+
+#define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
+static struct {
+ const char *name;
+ int len;
+ int opt;
+} smk_mount_opts[] = {
+ {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault},
+ A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute)
+};
+#undef A
+
+static int match_opt_prefix(char *s, int l, char **arg)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) {
+ size_t len = smk_mount_opts[i].len;
+ if (len > l || memcmp(s, smk_mount_opts[i].name, len))
+ continue;
+ if (len == l || s[len] != '=')
+ continue;
+ *arg = s + len + 1;
+ return smk_mount_opts[i].opt;
+ }
+ return Opt_error;
+}
+
+#ifdef CONFIG_SECURITY_SMACK_BRINGUP
+static char *smk_bu_mess[] = {
+ "Bringup Error", /* Unused */
+ "Bringup", /* SMACK_BRINGUP_ALLOW */
+ "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */
+ "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */
+};
+
+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;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+
+ smk_bu_mode(mode, acc);
+ pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
+ 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 = smack_cred(current_cred());
+ char acc[SMK_NUM_ACCESS_TYPE + 1];
+
+ if (rc <= 0)
+ return rc;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+
+ smk_bu_mode(mode, acc);
+ pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
+ 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 = smack_cred(current_cred());
+ struct smack_known *smk_task = smk_of_task_struct_obj(otp);
+ char acc[SMK_NUM_ACCESS_TYPE + 1];
+
+ if (rc <= 0)
+ return rc;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+
+ smk_bu_mode(mode, acc);
+ pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
+ tsp->smk_task->smk_known, 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 = smack_cred(current_cred());
+ struct inode_smack *isp = smack_inode(inode);
+ char acc[SMK_NUM_ACCESS_TYPE + 1];
+
+ if (isp->smk_flags & SMK_INODE_IMPURE)
+ pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
+ inode->i_sb->s_id, inode->i_ino, current->comm);
+
+ if (rc <= 0)
+ return rc;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+ if (rc == SMACK_UNCONFINED_SUBJECT &&
+ (mode & (MAY_WRITE | MAY_APPEND)))
+ isp->smk_flags |= SMK_INODE_IMPURE;
+
+ smk_bu_mode(mode, acc);
+
+ pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
+ tsp->smk_task->smk_known, isp->smk_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 = smack_cred(current_cred());
+ struct smack_known *sskp = tsp->smk_task;
+ struct inode *inode = file_inode(file);
+ struct inode_smack *isp = smack_inode(inode);
+ char acc[SMK_NUM_ACCESS_TYPE + 1];
+
+ if (isp->smk_flags & SMK_INODE_IMPURE)
+ pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
+ inode->i_sb->s_id, inode->i_ino, current->comm);
+
+ if (rc <= 0)
+ return rc;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+
+ smk_bu_mode(mode, acc);
+ pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
+ 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_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 = smack_cred(cred);
+ struct smack_known *sskp = tsp->smk_task;
+ struct inode *inode = file_inode(file);
+ struct inode_smack *isp = smack_inode(inode);
+ char acc[SMK_NUM_ACCESS_TYPE + 1];
+
+ if (isp->smk_flags & SMK_INODE_IMPURE)
+ pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
+ inode->i_sb->s_id, inode->i_ino, current->comm);
+
+ if (rc <= 0)
+ return rc;
+ if (rc > SMACK_UNCONFINED_OBJECT)
+ rc = 0;
+
+ smk_bu_mode(mode, acc);
+ pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
+ 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,
+ * NULL if there was no label to fetch, or an error code.
+ */
+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_opflags & IOP_XATTR))
+ return ERR_PTR(-EOPNOTSUPP);
+
+ buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS);
+ if (buffer == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
+ if (rc < 0)
+ skp = ERR_PTR(rc);
+ else if (rc == 0)
+ skp = NULL;
+ else
+ skp = smk_import_entry(buffer, rc);
+
+ kfree(buffer);
+
+ return skp;
+}
+
+/**
+ * init_inode_smack - initialize an inode security blob
+ * @inode: inode to extract the info from
+ * @skp: a pointer to the Smack label entry to use in the blob
+ *
+ */
+static void init_inode_smack(struct inode *inode, struct smack_known *skp)
+{
+ struct inode_smack *isp = smack_inode(inode);
+
+ isp->smk_inode = skp;
+ isp->smk_flags = 0;
+}
+
+/**
+ * init_task_smack - initialize a task security blob
+ * @tsp: blob to initialize
+ * @task: a pointer to the Smack label for the running task
+ * @forked: a pointer to the Smack label for the forked task
+ *
+ */
+static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
+ struct smack_known *forked)
+{
+ tsp->smk_task = task;
+ tsp->smk_forked = forked;
+ INIT_LIST_HEAD(&tsp->smk_rules);
+ INIT_LIST_HEAD(&tsp->smk_relabel);
+ mutex_init(&tsp->smk_rules_lock);
+}
+
+/**
+ * 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;
+
+ list_for_each_entry_rcu(orp, ohead, list) {
+ nrp = kmem_cache_zalloc(smack_rule_cache, gfp);
+ if (nrp == NULL) {
+ rc = -ENOMEM;
+ break;
+ }
+ *nrp = *orp;
+ list_add_rcu(&nrp->list, nhead);
+ }
+ return rc;
+}
+
+/**
+ * smk_copy_relabel - copy smk_relabel labels list
+ * @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_relabel(struct list_head *nhead, struct list_head *ohead,
+ gfp_t gfp)
+{
+ struct smack_known_list_elem *nklep;
+ struct smack_known_list_elem *oklep;
+
+ list_for_each_entry(oklep, ohead, list) {
+ nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
+ if (nklep == NULL) {
+ smk_destroy_label_list(nhead);
+ return -ENOMEM;
+ }
+ nklep->smk_label = oklep->smk_label;
+ list_add(&nklep->list, nhead);
+ }
+
+ return 0;
+}
+
+/**
+ * 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)
+{
+ if (mode & PTRACE_MODE_ATTACH)
+ return MAY_READWRITE;
+ if (mode & PTRACE_MODE_READ)
+ return MAY_READ;
+
+ 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;
+ const struct cred *tracercred;
+
+ if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
+ smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
+ smk_ad_setfield_u_tsk(&ad, tracer);
+ saip = &ad;
+ }
+
+ rcu_read_lock();
+ tracercred = __task_cred(tracer);
+ tsp = smack_cred(tracercred);
+ 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 (smack_privileged_cred(CAP_SYS_PTRACE, tracercred))
+ rc = 0;
+ else
+ rc = -EACCES;
+
+ if (saip)
+ smack_log(tracer_known->smk_known,
+ tracee_known->smk_known,
+ 0, rc, saip);
+
+ rcu_read_unlock();
+ 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);
+
+ rcu_read_unlock();
+ 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)
+{
+ struct smack_known *skp;
+
+ skp = smk_of_task_struct_obj(ctp);
+
+ return smk_ptrace_rule_check(current, skp, mode, __func__);
+}
+
+/**
+ * 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)
+{
+ struct smack_known *skp;
+
+ skp = smk_of_task(smack_cred(current_cred()));
+
+ return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
+}
+
+/**
+ * smack_syslog - Smack approval on syslog
+ * @typefrom_file: unused
+ *
+ * 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 = smack_superblock(sb);
+
+ 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_SB_INITIALIZED will be zero from kzalloc.
+ */
+
+ return 0;
+}
+
+struct smack_mnt_opts {
+ const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute;
+};
+
+static void smack_free_mnt_opts(void *mnt_opts)
+{
+ struct smack_mnt_opts *opts = mnt_opts;
+ kfree(opts->fsdefault);
+ kfree(opts->fsfloor);
+ kfree(opts->fshat);
+ kfree(opts->fsroot);
+ kfree(opts->fstransmute);
+ kfree(opts);
+}
+
+static int smack_add_opt(int token, const char *s, void **mnt_opts)
+{
+ struct smack_mnt_opts *opts = *mnt_opts;
+
+ if (!opts) {
+ opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
+ if (!opts)
+ return -ENOMEM;
+ *mnt_opts = opts;
+ }
+ if (!s)
+ return -ENOMEM;
+
+ switch (token) {
+ case Opt_fsdefault:
+ if (opts->fsdefault)
+ goto out_opt_err;
+ opts->fsdefault = s;
+ break;
+ case Opt_fsfloor:
+ if (opts->fsfloor)
+ goto out_opt_err;
+ opts->fsfloor = s;
+ break;
+ case Opt_fshat:
+ if (opts->fshat)
+ goto out_opt_err;
+ opts->fshat = s;
+ break;
+ case Opt_fsroot:
+ if (opts->fsroot)
+ goto out_opt_err;
+ opts->fsroot = s;
+ break;
+ case Opt_fstransmute:
+ if (opts->fstransmute)
+ goto out_opt_err;
+ opts->fstransmute = s;
+ break;
+ }
+ return 0;
+
+out_opt_err:
+ pr_warn("Smack: duplicate mount options\n");
+ return -EINVAL;
+}
+
+/**
+ * smack_fs_context_submount - Initialise security data for a filesystem context
+ * @fc: The filesystem context.
+ * @reference: reference superblock
+ *
+ * Returns 0 on success or -ENOMEM on error.
+ */
+static int smack_fs_context_submount(struct fs_context *fc,
+ struct super_block *reference)
+{
+ struct superblock_smack *sbsp;
+ struct smack_mnt_opts *ctx;
+ struct inode_smack *isp;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+ fc->security = ctx;
+
+ sbsp = smack_superblock(reference);
+ isp = smack_inode(reference->s_root->d_inode);
+
+ if (sbsp->smk_default) {
+ ctx->fsdefault = kstrdup(sbsp->smk_default->smk_known, GFP_KERNEL);
+ if (!ctx->fsdefault)
+ return -ENOMEM;
+ }
+
+ if (sbsp->smk_floor) {
+ ctx->fsfloor = kstrdup(sbsp->smk_floor->smk_known, GFP_KERNEL);
+ if (!ctx->fsfloor)
+ return -ENOMEM;
+ }
+
+ if (sbsp->smk_hat) {
+ ctx->fshat = kstrdup(sbsp->smk_hat->smk_known, GFP_KERNEL);
+ if (!ctx->fshat)
+ return -ENOMEM;
+ }
+
+ if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
+ if (sbsp->smk_root) {
+ ctx->fstransmute = kstrdup(sbsp->smk_root->smk_known, GFP_KERNEL);
+ if (!ctx->fstransmute)
+ return -ENOMEM;
+ }
+ }
+ return 0;
+}
+
+/**
+ * smack_fs_context_dup - Duplicate the security data on fs_context duplication
+ * @fc: The new filesystem context.
+ * @src_fc: The source filesystem context being duplicated.
+ *
+ * Returns 0 on success or -ENOMEM on error.
+ */
+static int smack_fs_context_dup(struct fs_context *fc,
+ struct fs_context *src_fc)
+{
+ struct smack_mnt_opts *dst, *src = src_fc->security;
+
+ if (!src)
+ return 0;
+
+ fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
+ if (!fc->security)
+ return -ENOMEM;
+ dst = fc->security;
+
+ if (src->fsdefault) {
+ dst->fsdefault = kstrdup(src->fsdefault, GFP_KERNEL);
+ if (!dst->fsdefault)
+ return -ENOMEM;
+ }
+ if (src->fsfloor) {
+ dst->fsfloor = kstrdup(src->fsfloor, GFP_KERNEL);
+ if (!dst->fsfloor)
+ return -ENOMEM;
+ }
+ if (src->fshat) {
+ dst->fshat = kstrdup(src->fshat, GFP_KERNEL);
+ if (!dst->fshat)
+ return -ENOMEM;
+ }
+ if (src->fsroot) {
+ dst->fsroot = kstrdup(src->fsroot, GFP_KERNEL);
+ if (!dst->fsroot)
+ return -ENOMEM;
+ }
+ if (src->fstransmute) {
+ dst->fstransmute = kstrdup(src->fstransmute, GFP_KERNEL);
+ if (!dst->fstransmute)
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static const struct fs_parameter_spec smack_fs_parameters[] = {
+ fsparam_string("smackfsdef", Opt_fsdefault),
+ fsparam_string("smackfsdefault", Opt_fsdefault),
+ fsparam_string("smackfsfloor", Opt_fsfloor),
+ fsparam_string("smackfshat", Opt_fshat),
+ fsparam_string("smackfsroot", Opt_fsroot),
+ fsparam_string("smackfstransmute", Opt_fstransmute),
+ {}
+};
+
+/**
+ * smack_fs_context_parse_param - Parse a single mount parameter
+ * @fc: The new filesystem context being constructed.
+ * @param: The parameter.
+ *
+ * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on
+ * error.
+ */
+static int smack_fs_context_parse_param(struct fs_context *fc,
+ struct fs_parameter *param)
+{
+ struct fs_parse_result result;
+ int opt, rc;
+
+ opt = fs_parse(fc, smack_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ rc = smack_add_opt(opt, param->string, &fc->security);
+ if (!rc)
+ param->string = NULL;
+ return rc;
+}
+
+static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
+{
+ char *from = options, *to = options;
+ bool first = true;
+
+ while (1) {
+ char *next = strchr(from, ',');
+ int token, len, rc;
+ char *arg = NULL;
+
+ if (next)
+ len = next - from;
+ else
+ len = strlen(from);
+
+ token = match_opt_prefix(from, len, &arg);
+ if (token != Opt_error) {
+ arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
+ rc = smack_add_opt(token, arg, mnt_opts);
+ if (unlikely(rc)) {
+ kfree(arg);
+ if (*mnt_opts)
+ smack_free_mnt_opts(*mnt_opts);
+ *mnt_opts = NULL;
+ return rc;
+ }
+ } else {
+ if (!first) { // copy with preceding comma
+ from--;
+ len++;
+ }
+ if (to != from)
+ memmove(to, from, len);
+ to += len;
+ first = false;
+ }
+ if (!from[len])
+ break;
+ from += len + 1;
+ }
+ *to = '\0';
+ return 0;
+}
+
+/**
+ * smack_set_mnt_opts - set Smack specific mount options
+ * @sb: the file system superblock
+ * @mnt_opts: Smack mount options
+ * @kern_flags: mount option from kernel space or user space
+ * @set_kern_flags: where to store converted mount opts
+ *
+ * Returns 0 on success, an error code on failure
+ *
+ * Allow filesystems with binary mount data to explicitly set Smack mount
+ * labels.
+ */
+static int smack_set_mnt_opts(struct super_block *sb,
+ void *mnt_opts,
+ unsigned long kern_flags,
+ unsigned long *set_kern_flags)
+{
+ struct dentry *root = sb->s_root;
+ struct inode *inode = d_backing_inode(root);
+ struct superblock_smack *sp = smack_superblock(sb);
+ struct inode_smack *isp;
+ struct smack_known *skp;
+ struct smack_mnt_opts *opts = mnt_opts;
+ bool transmute = false;
+
+ if (sp->smk_flags & SMK_SB_INITIALIZED)
+ return 0;
+
+ if (!smack_privileged(CAP_MAC_ADMIN)) {
+ /*
+ * Unprivileged mounts don't get to specify Smack values.
+ */
+ if (opts)
+ return -EPERM;
+ /*
+ * Unprivileged mounts get root and default from the caller.
+ */
+ skp = smk_of_current();
+ sp->smk_root = skp;
+ sp->smk_default = skp;
+ /*
+ * For a handful of fs types with no user-controlled
+ * backing store it's okay to trust security labels
+ * in the filesystem. The rest are untrusted.
+ */
+ if (sb->s_user_ns != &init_user_ns &&
+ sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
+ sb->s_magic != RAMFS_MAGIC) {
+ transmute = true;
+ sp->smk_flags |= SMK_SB_UNTRUSTED;
+ }
+ }
+
+ sp->smk_flags |= SMK_SB_INITIALIZED;
+
+ if (opts) {
+ if (opts->fsdefault) {
+ skp = smk_import_entry(opts->fsdefault, 0);
+ if (IS_ERR(skp))
+ return PTR_ERR(skp);
+ sp->smk_default = skp;
+ }
+ if (opts->fsfloor) {
+ skp = smk_import_entry(opts->fsfloor, 0);
+ if (IS_ERR(skp))
+ return PTR_ERR(skp);
+ sp->smk_floor = skp;
+ }
+ if (opts->fshat) {
+ skp = smk_import_entry(opts->fshat, 0);
+ if (IS_ERR(skp))
+ return PTR_ERR(skp);
+ sp->smk_hat = skp;
+ }
+ if (opts->fsroot) {
+ skp = smk_import_entry(opts->fsroot, 0);
+ if (IS_ERR(skp))
+ return PTR_ERR(skp);
+ sp->smk_root = skp;
+ }
+ if (opts->fstransmute) {
+ skp = smk_import_entry(opts->fstransmute, 0);
+ if (IS_ERR(skp))
+ return PTR_ERR(skp);
+ sp->smk_root = skp;
+ transmute = true;
+ }
+ }
+
+ /*
+ * Initialize the root inode.
+ */
+ init_inode_smack(inode, sp->smk_root);
+
+ if (transmute) {
+ isp = smack_inode(inode);
+ 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 = smack_superblock(dentry->d_sb);
+ 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_creds_for_exec - Update bprm->cred if needed for exec
+ * @bprm: the exec information
+ *
+ * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
+ */
+static int smack_bprm_creds_for_exec(struct linux_binprm *bprm)
+{
+ struct inode *inode = file_inode(bprm->file);
+ struct task_smack *bsp = smack_cred(bprm->cred);
+ struct inode_smack *isp;
+ struct superblock_smack *sbsp;
+ int rc;
+
+ isp = smack_inode(inode);
+ if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
+ return 0;
+
+ sbsp = smack_superblock(inode->i_sb);
+ if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
+ isp->smk_task != sbsp->smk_root)
+ return 0;
+
+ if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
+ 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;
+ }
+ if (bprm->unsafe & ~LSM_UNSAFE_PTRACE)
+ return -EPERM;
+
+ bsp->smk_task = isp->smk_task;
+ bprm->per_clear |= PER_CLEAR_ON_SETID;
+
+ /* Decide if this is a secure exec. */
+ if (bsp->smk_task != bsp->smk_forked)
+ bprm->secureexec = 1;
+
+ return 0;
+}
+
+/*
+ * Inode hooks
+ */
+
+/**
+ * smack_inode_alloc_security - allocate an inode blob
+ * @inode: the inode in need of a blob
+ *
+ * Returns 0
+ */
+static int smack_inode_alloc_security(struct inode *inode)
+{
+ struct smack_known *skp = smk_of_current();
+
+ init_inode_smack(inode, skp);
+ return 0;
+}
+
+/**
+ * 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 task_smack *tsp = smack_cred(current_cred());
+ struct inode_smack *issp = smack_inode(inode);
+ struct smack_known *skp = smk_of_task(tsp);
+ 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) {
+ /*
+ * If equal, transmuting already occurred in
+ * smack_dentry_create_files_as(). No need to check again.
+ */
+ if (tsp->smk_task != tsp->smk_transmuted) {
+ rcu_read_lock();
+ may = smk_access_entry(skp->smk_known, dsp->smk_known,
+ &skp->smk_rules);
+ rcu_read_unlock();
+ }
+
+ /*
+ * In addition to having smk_task equal to smk_transmuted,
+ * if the access rule allows transmutation and the directory
+ * requests transmutation then by all means transmute.
+ * Mark the inode as changed.
+ */
+ if ((tsp->smk_task == tsp->smk_transmuted) ||
+ (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
+ smk_inode_transmutable(dir))) {
+ /*
+ * The caller of smack_dentry_create_files_as()
+ * should have overridden the current cred, so the
+ * inode label was already set correctly in
+ * smack_inode_alloc_security().
+ */
+ if (tsp->smk_task != tsp->smk_transmuted)
+ 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(d_backing_inode(old_dentry));
+ rc = smk_curacc(isp, MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
+
+ if (rc == 0 && d_is_positive(new_dentry)) {
+ isp = smk_of_inode(d_backing_inode(new_dentry));
+ smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
+ rc = smk_curacc(isp, MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(new_dentry), 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 = d_backing_inode(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 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(d_backing_inode(dentry)), MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(dentry), 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(d_backing_inode(old_dentry));
+ rc = smk_curacc(isp, MAY_READWRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
+
+ if (rc == 0 && d_is_positive(new_dentry)) {
+ isp = smk_of_inode(d_backing_inode(new_dentry));
+ smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
+ rc = smk_curacc(isp, MAY_READWRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(new_dentry), 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, an error code otherwise
+ */
+static int smack_inode_permission(struct inode *inode, int mask)
+{
+ struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
+ 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;
+
+ if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
+ if (smk_of_inode(inode) != sbsp->smk_root)
+ return -EACCES;
+ }
+
+ /* 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(d_backing_inode(dentry)), MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
+ return rc;
+}
+
+/**
+ * smack_inode_getattr - Smack check for getting attributes
+ * @path: path to extract the info from
+ *
+ * Returns 0 if access is permitted, an error code otherwise
+ */
+static int smack_inode_getattr(const struct path *path)
+{
+ struct smk_audit_info ad;
+ struct inode *inode = d_backing_inode(path->dentry);
+ int rc;
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
+ smk_ad_setfield_u_fs_path(&ad, *path);
+ rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
+ rc = smk_bu_inode(inode, MAY_READ, rc);
+ return rc;
+}
+
+/**
+ * smack_inode_setxattr - Smack check for setting xattrs
+ * @mnt_userns: active user namespace
+ * @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 user_namespace *mnt_userns,
+ 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 (IS_ERR(skp))
+ rc = PTR_ERR(skp);
+ else 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(d_backing_inode(dentry)), MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(dentry), 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 = smack_inode(d_backing_inode(dentry));
+
+ 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 (!IS_ERR(skp))
+ isp->smk_inode = skp;
+ } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
+ skp = smk_import_entry(value, size);
+ if (!IS_ERR(skp))
+ isp->smk_task = skp;
+ } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
+ skp = smk_import_entry(value, size);
+ if (!IS_ERR(skp))
+ isp->smk_mmap = skp;
+ }
+
+ 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(d_backing_inode(dentry)), MAY_READ, &ad);
+ rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
+ return rc;
+}
+
+/**
+ * smack_inode_removexattr - Smack check on removexattr
+ * @mnt_userns: active user namespace
+ * @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 user_namespace *mnt_userns,
+ 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(mnt_userns, 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(d_backing_inode(dentry)), MAY_WRITE, &ad);
+ rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
+ if (rc != 0)
+ return rc;
+
+ isp = smack_inode(d_backing_inode(dentry));
+ /*
+ * Don't do anything special for these.
+ * XATTR_NAME_SMACKIPIN
+ * XATTR_NAME_SMACKIPOUT
+ */
+ if (strcmp(name, XATTR_NAME_SMACK) == 0) {
+ struct super_block *sbp = dentry->d_sb;
+ struct superblock_smack *sbsp = smack_superblock(sbp);
+
+ isp->smk_inode = sbsp->smk_default;
+ } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 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
+ * @mnt_userns: active user namespace
+ * @inode: the object
+ * @name: attribute name
+ * @buffer: where to put the result
+ * @alloc: duplicate memory
+ *
+ * Returns the size of the attribute or an error code
+ */
+static int smack_inode_getsecurity(struct user_namespace *mnt_userns,
+ 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;
+ struct inode_smack *ispp;
+ size_t label_len;
+ char *label = NULL;
+
+ if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
+ isp = smk_of_inode(inode);
+ } else if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
+ ispp = smack_inode(inode);
+ if (ispp->smk_flags & SMK_INODE_TRANSMUTE)
+ label = TRANS_TRUE;
+ else
+ label = "";
+ } else {
+ /*
+ * 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;
+ }
+
+ if (!label)
+ label = isp->smk_known;
+
+ label_len = strlen(label);
+
+ if (alloc) {
+ *buffer = kstrdup(label, GFP_KERNEL);
+ if (*buffer == NULL)
+ return -ENOMEM;
+ }
+
+ return label_len;
+}
+
+
+/**
+ * smack_inode_listsecurity - list the Smack attributes
+ * @inode: the object
+ * @buffer: where they go
+ * @buffer_size: size of buffer
+ */
+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(struct inode *inode, u32 *secid)
+{
+ struct smack_known *skp = smk_of_inode(inode);
+
+ *secid = skp->smk_secid;
+}
+
+/*
+ * File Hooks
+ */
+
+/*
+ * There is no smack_file_permission hook
+ *
+ * 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.
+ */
+
+/**
+ * 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.
+ *
+ * f_security is the owner security information. It
+ * isn't used on file access checks, it's for send_sigio.
+ *
+ * Returns 0
+ */
+static int smack_file_alloc_security(struct file *file)
+{
+ struct smack_known **blob = smack_file(file);
+
+ *blob = smk_of_current();
+ return 0;
+}
+
+/**
+ * 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;
+ struct inode *inode = file_inode(file);
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ 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(smk_of_inode(inode), MAY_WRITE, &ad);
+ rc = smk_bu_file(file, MAY_WRITE, rc);
+ }
+
+ if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
+ rc = smk_curacc(smk_of_inode(inode), 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;
+ struct inode *inode = file_inode(file);
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
+ smk_ad_setfield_u_fs_path(&ad, file->f_path);
+ rc = smk_curacc(smk_of_inode(inode), 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;
+ struct inode *inode = file_inode(file);
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 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(smk_of_inode(inode), 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(smk_of_inode(inode), 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.
+ * @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.
+ *
+ * The @file may be NULL, e.g. if mapping anonymous memory.
+ *
+ * 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;
+ struct superblock_smack *sbsp;
+ int may;
+ int mmay;
+ int tmay;
+ int rc;
+
+ if (file == NULL)
+ return 0;
+
+ if (unlikely(IS_PRIVATE(file_inode(file))))
+ return 0;
+
+ isp = smack_inode(file_inode(file));
+ if (isp->smk_mmap == NULL)
+ return 0;
+ sbsp = smack_superblock(file_inode(file)->i_sb);
+ if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
+ isp->smk_mmap != sbsp->smk_root)
+ return -EACCES;
+ mkp = isp->smk_mmap;
+
+ tsp = smack_cred(current_cred());
+ 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
+ *
+ */
+static void smack_file_set_fowner(struct file *file)
+{
+ struct smack_known **blob = smack_file(file);
+
+ *blob = smk_of_current();
+}
+
+/**
+ * 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 **blob;
+ struct smack_known *skp;
+ struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
+ const struct cred *tcred;
+ 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 */
+ blob = smack_file(file);
+ skp = *blob;
+ rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
+ rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
+
+ rcu_read_lock();
+ tcred = __task_cred(tsk);
+ if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred))
+ rc = 0;
+ rcu_read_unlock();
+
+ 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_DELIVER, 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;
+ struct inode *inode = file_inode(file);
+ struct socket *sock;
+ struct task_smack *tsp;
+ struct socket_smack *ssp;
+
+ if (unlikely(IS_PRIVATE(inode)))
+ return 0;
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
+ smk_ad_setfield_u_fs_path(&ad, file->f_path);
+
+ if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
+ sock = SOCKET_I(inode);
+ ssp = sock->sk->sk_security;
+ tsp = smack_cred(current_cred());
+ /*
+ * If the receiving process can't write to the
+ * passed socket or if the passed socket can't
+ * write to the receiving process don't accept
+ * the passed socket.
+ */
+ rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
+ rc = smk_bu_file(file, may, rc);
+ if (rc < 0)
+ return rc;
+ rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
+ rc = smk_bu_file(file, may, rc);
+ return rc;
+ }
+ /*
+ * 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(smk_of_inode(inode), may, &ad);
+ rc = smk_bu_file(file, may, rc);
+ return rc;
+}
+
+/**
+ * smack_file_open - Smack dentry open processing
+ * @file: the object
+ *
+ * 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 if current has access, error code otherwise
+ */
+static int smack_file_open(struct file *file)
+{
+ struct task_smack *tsp = smack_cred(file->f_cred);
+ struct inode *inode = file_inode(file);
+ 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_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
+ rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
+
+ return rc;
+}
+
+/*
+ * Task hooks
+ */
+
+/**
+ * smack_cred_alloc_blank - "allocate" blank task-level security credentials
+ * @cred: 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)
+{
+ init_task_smack(smack_cred(cred), NULL, NULL);
+ 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 = smack_cred(cred);
+ struct smack_rule *rp;
+ struct list_head *l;
+ struct list_head *n;
+
+ smk_destroy_label_list(&tsp->smk_relabel);
+
+ list_for_each_safe(l, n, &tsp->smk_rules) {
+ rp = list_entry(l, struct smack_rule, list);
+ list_del(&rp->list);
+ kmem_cache_free(smack_rule_cache, rp);
+ }
+}
+
+/**
+ * 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 = smack_cred(old);
+ struct task_smack *new_tsp = smack_cred(new);
+ int rc;
+
+ init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
+
+ rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
+ if (rc != 0)
+ return rc;
+
+ rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
+ gfp);
+ return rc;
+}
+
+/**
+ * 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 = smack_cred(old);
+ struct task_smack *new_tsp = smack_cred(new);
+
+ 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_cred_getsecid - get the secid corresponding to a creds structure
+ * @cred: the object creds
+ * @secid: where to put the result
+ *
+ * Sets the secid to contain a u32 version of the smack label.
+ */
+static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
+{
+ struct smack_known *skp;
+
+ rcu_read_lock();
+ skp = smk_of_task(smack_cred(cred));
+ *secid = skp->smk_secid;
+ rcu_read_unlock();
+}
+
+/**
+ * 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 = smack_cred(new);
+
+ new_tsp->smk_task = smack_from_secid(secid);
+ 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 = smack_inode(inode);
+ struct task_smack *tsp = smack_cred(new);
+
+ 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_struct_obj(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_current_getsecid_subj - get the subjective secid of the current task
+ * @secid: where to put the result
+ *
+ * Sets the secid to contain a u32 version of the task's subjective smack label.
+ */
+static void smack_current_getsecid_subj(u32 *secid)
+{
+ struct smack_known *skp = smk_of_current();
+
+ *secid = skp->smk_secid;
+}
+
+/**
+ * smack_task_getsecid_obj - get the objective secid of the task
+ * @p: the task
+ * @secid: where to put the result
+ *
+ * Sets the secid to contain a u32 version of the task's objective smack label.
+ */
+static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid)
+{
+ struct smack_known *skp = smk_of_task_struct_obj(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)
+{
+ return smk_curacc_on_task(p, MAY_WRITE, __func__);
+}
+
+/**
+ * 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)
+{
+ return smk_curacc_on_task(p, MAY_WRITE, __func__);
+}
+
+/**
+ * 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
+ *
+ * Return 0 if read access is permitted
+ */
+static int smack_task_setscheduler(struct task_struct *p)
+{
+ return smk_curacc_on_task(p, MAY_WRITE, __func__);
+}
+
+/**
+ * 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
+ * @cred: identifies the cred to use in lieu of current's
+ *
+ * Return 0 if write access is permitted
+ *
+ */
+static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
+ int sig, const struct cred *cred)
+{
+ struct smk_audit_info ad;
+ struct smack_known *skp;
+ struct smack_known *tkp = smk_of_task_struct_obj(p);
+ int rc;
+
+ if (!sig)
+ return 0; /* null signal; existence test */
+
+ 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 (cred == NULL) {
+ rc = smk_curacc(tkp, MAY_DELIVER, &ad);
+ rc = smk_bu_task(p, MAY_DELIVER, rc);
+ return rc;
+ }
+ /*
+ * If the cred isn't NULL we're dealing with some USB IO
+ * specific behavior. This is not clean. For one thing
+ * we can't take privilege into account.
+ */
+ skp = smk_of_task(smack_cred(cred));
+ rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
+ rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
+ return rc;
+}
+
+/**
+ * smack_task_to_inode - copy task smack into the inode blob
+ * @p: task to copy from
+ * @inode: inode to copy to
+ *
+ * Sets the smack pointer in the inode security blob
+ */
+static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
+{
+ struct inode_smack *isp = smack_inode(inode);
+ struct smack_known *skp = smk_of_task_struct_obj(p);
+
+ isp->smk_inode = skp;
+ isp->smk_flags |= SMK_INODE_INSTANT;
+}
+
+/*
+ * 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;
+
+ /*
+ * Sockets created by kernel threads receive web label.
+ */
+ if (unlikely(current->flags & PF_KTHREAD)) {
+ ssp->smk_in = &smack_known_web;
+ ssp->smk_out = &smack_known_web;
+ } else {
+ 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)
+{
+#ifdef SMACK_IPV6_PORT_LABELING
+ struct smk_port_label *spp;
+
+ if (sk->sk_family == PF_INET6) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
+ if (spp->smk_sock != sk)
+ continue;
+ spp->smk_can_reuse = 1;
+ break;
+ }
+ rcu_read_unlock();
+ }
+#endif
+ kfree(sk->sk_security);
+}
+
+/**
+ * smack_sk_clone_security - Copy security context
+ * @sk: the old socket
+ * @newsk: the new socket
+ *
+ * Copy the security context of the old socket pointer to the cloned
+ */
+static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk)
+{
+ struct socket_smack *ssp_old = sk->sk_security;
+ struct socket_smack *ssp_new = newsk->sk_security;
+
+ *ssp_new = *ssp_old;
+}
+
+/**
+* smack_ipv4host_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_ipv4host_label(struct sockaddr_in *sip)
+{
+ struct smk_net4addr *snp;
+ struct in_addr *siap = &sip->sin_addr;
+
+ if (siap->s_addr == 0)
+ return NULL;
+
+ list_for_each_entry_rcu(snp, &smk_net4addr_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.s_addr ==
+ (siap->s_addr & snp->smk_mask.s_addr))
+ return snp->smk_label;
+
+ return NULL;
+}
+
+/*
+ * smk_ipv6_localhost - Check for local ipv6 host address
+ * @sip: the address
+ *
+ * Returns boolean true if this is the localhost address
+ */
+static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
+{
+ __be16 *be16p = (__be16 *)&sip->sin6_addr;
+ __be32 *be32p = (__be32 *)&sip->sin6_addr;
+
+ if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
+ ntohs(be16p[7]) == 1)
+ return true;
+ return false;
+}
+
+/**
+* smack_ipv6host_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_ipv6host_label(struct sockaddr_in6 *sip)
+{
+ struct smk_net6addr *snp;
+ struct in6_addr *sap = &sip->sin6_addr;
+ int i;
+ int found = 0;
+
+ /*
+ * It's local. Don't look for a host label.
+ */
+ if (smk_ipv6_localhost(sip))
+ return NULL;
+
+ list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
+ /*
+ * If the label is NULL the entry has
+ * been renounced. Ignore it.
+ */
+ if (snp->smk_label == NULL)
+ continue;
+ /*
+ * 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
+ */
+ for (found = 1, i = 0; i < 8; i++) {
+ if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
+ snp->smk_host.s6_addr16[i]) {
+ found = 0;
+ break;
+ }
+ }
+ if (found)
+ return snp->smk_label;
+ }
+
+ return NULL;
+}
+
+/**
+ * smack_netlbl_add - Set the secattr on a socket
+ * @sk: the socket
+ *
+ * Attach the outbound smack value (smk_out) to the socket.
+ *
+ * Returns 0 on success or an error code
+ */
+static int smack_netlbl_add(struct sock *sk)
+{
+ struct socket_smack *ssp = sk->sk_security;
+ struct smack_known *skp = ssp->smk_out;
+ int rc;
+
+ local_bh_disable();
+ bh_lock_sock_nested(sk);
+
+ rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
+ switch (rc) {
+ case 0:
+ ssp->smk_state = SMK_NETLBL_LABELED;
+ break;
+ case -EDESTADDRREQ:
+ ssp->smk_state = SMK_NETLBL_REQSKB;
+ rc = 0;
+ break;
+ }
+
+ bh_unlock_sock(sk);
+ local_bh_enable();
+
+ return rc;
+}
+
+/**
+ * smack_netlbl_delete - Remove the secattr from a socket
+ * @sk: the socket
+ *
+ * Remove the outbound smack value from a socket
+ */
+static void smack_netlbl_delete(struct sock *sk)
+{
+ struct socket_smack *ssp = sk->sk_security;
+
+ /*
+ * Take the label off the socket if one is set.
+ */
+ if (ssp->smk_state != SMK_NETLBL_LABELED)
+ return;
+
+ local_bh_disable();
+ bh_lock_sock_nested(sk);
+ netlbl_sock_delattr(sk);
+ bh_unlock_sock(sk);
+ local_bh_enable();
+ ssp->smk_state = SMK_NETLBL_UNLABELED;
+}
+
+/**
+ * smk_ipv4_check - Perform IPv4 host 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 smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
+{
+ struct smack_known *skp;
+ int rc = 0;
+ struct smack_known *hkp;
+ struct socket_smack *ssp = sk->sk_security;
+ struct smk_audit_info ad;
+
+ rcu_read_lock();
+ hkp = smack_ipv4host_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
+ skp = ssp->smk_out;
+ rc = smk_access(skp, hkp, MAY_WRITE, &ad);
+ rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
+ /*
+ * Clear the socket netlabel if it's set.
+ */
+ if (!rc)
+ smack_netlbl_delete(sk);
+ }
+ rcu_read_unlock();
+
+ return rc;
+}
+
+/**
+ * smk_ipv6_check - check Smack access
+ * @subject: subject Smack label
+ * @object: object Smack label
+ * @address: address
+ * @act: the action being taken
+ *
+ * Check an IPv6 access
+ */
+static int smk_ipv6_check(struct smack_known *subject,
+ struct smack_known *object,
+ struct sockaddr_in6 *address, int act)
+{
+#ifdef CONFIG_AUDIT
+ struct lsm_network_audit net;
+#endif
+ struct smk_audit_info ad;
+ int rc;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
+ ad.a.u.net->family = PF_INET6;
+ ad.a.u.net->dport = address->sin6_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(subject, object, MAY_WRITE, &ad);
+ rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
+ return rc;
+}
+
+#ifdef SMACK_IPV6_PORT_LABELING
+/**
+ * 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.
+ */
+ rcu_read_lock();
+ list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
+ if (sk != spp->smk_sock)
+ continue;
+ spp->smk_in = ssp->smk_in;
+ spp->smk_out = ssp->smk_out;
+ rcu_read_unlock();
+ return;
+ }
+ /*
+ * A NULL address is only used for updating existing
+ * bound entries. If there isn't one, it's OK.
+ */
+ rcu_read_unlock();
+ 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.
+ */
+ rcu_read_lock();
+ list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
+ if (spp->smk_port != port || spp->smk_sock_type != sock->type)
+ continue;
+ if (spp->smk_can_reuse != 1) {
+ rcu_read_unlock();
+ return;
+ }
+ spp->smk_port = port;
+ spp->smk_sock = sk;
+ spp->smk_in = ssp->smk_in;
+ spp->smk_out = ssp->smk_out;
+ spp->smk_can_reuse = 0;
+ rcu_read_unlock();
+ return;
+ }
+ rcu_read_unlock();
+ /*
+ * 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;
+ spp->smk_sock_type = sock->type;
+ spp->smk_can_reuse = 0;
+
+ mutex_lock(&smack_ipv6_lock);
+ list_add_rcu(&spp->list, &smk_ipv6_port_list);
+ mutex_unlock(&smack_ipv6_lock);
+ return;
+}
+
+/**
+ * smk_ipv6_port_check - check Smack port access
+ * @sk: socket
+ * @address: address
+ * @act: the action being taken
+ *
+ * Create or update the port list entry
+ */
+static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
+ int act)
+{
+ struct smk_port_label *spp;
+ struct socket_smack *ssp = sk->sk_security;
+ struct smack_known *skp = NULL;
+ unsigned short port;
+ struct smack_known *object;
+
+ if (act == SMK_RECEIVING) {
+ skp = smack_ipv6host_label(address);
+ object = ssp->smk_in;
+ } else {
+ skp = ssp->smk_out;
+ object = smack_ipv6host_label(address);
+ }
+
+ /*
+ * The other end is a single label host.
+ */
+ if (skp != NULL && object != NULL)
+ return smk_ipv6_check(skp, object, address, act);
+ if (skp == NULL)
+ skp = smack_net_ambient;
+ if (object == NULL)
+ object = smack_net_ambient;
+
+ /*
+ * It's remote, so port lookup does no good.
+ */
+ if (!smk_ipv6_localhost(address))
+ return smk_ipv6_check(skp, object, address, act);
+
+ /*
+ * It's local so the send check has to have passed.
+ */
+ if (act == SMK_RECEIVING)
+ return 0;
+
+ port = ntohs(address->sin6_port);
+ rcu_read_lock();
+ list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
+ if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
+ continue;
+ object = spp->smk_in;
+ if (act == SMK_CONNECTING)
+ ssp->smk_packet = spp->smk_out;
+ break;
+ }
+ rcu_read_unlock();
+
+ return smk_ipv6_check(skp, object, address, act);
+}
+#endif
+
+/**
+ * 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 = smack_inode(inode);
+ 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 (IS_ERR(skp))
+ return PTR_ERR(skp);
+
+ 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_netlbl_add(sock->sk);
+ if (rc != 0)
+ printk(KERN_WARNING
+ "Smack: \"%s\" netlbl error %d.\n",
+ __func__, -rc);
+ }
+ } else
+ return -EOPNOTSUPP;
+
+#ifdef SMACK_IPV6_PORT_LABELING
+ if (sock->sk->sk_family == PF_INET6)
+ smk_ipv6_port_label(sock, NULL);
+#endif
+
+ 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)
+{
+ struct socket_smack *ssp;
+
+ if (sock->sk == NULL)
+ return 0;
+
+ /*
+ * Sockets created by kernel threads receive web label.
+ */
+ if (unlikely(current->flags & PF_KTHREAD)) {
+ ssp = sock->sk->sk_security;
+ ssp->smk_in = &smack_known_web;
+ ssp->smk_out = &smack_known_web;
+ }
+
+ if (family != PF_INET)
+ return 0;
+ /*
+ * Set the outbound netlbl.
+ */
+ return smack_netlbl_add(sock->sk);
+}
+
+/**
+ * smack_socket_socketpair - create socket pair
+ * @socka: one socket
+ * @sockb: another socket
+ *
+ * Cross reference the peer labels for SO_PEERSEC
+ *
+ * Returns 0
+ */
+static int smack_socket_socketpair(struct socket *socka,
+ struct socket *sockb)
+{
+ struct socket_smack *asp = socka->sk->sk_security;
+ struct socket_smack *bsp = sockb->sk->sk_security;
+
+ asp->smk_packet = bsp->smk_out;
+ bsp->smk_packet = asp->smk_out;
+
+ return 0;
+}
+
+#ifdef SMACK_IPV6_PORT_LABELING
+/**
+ * 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 on success, and error code otherwise
+ */
+static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
+ int addrlen)
+{
+ if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
+ if (addrlen < SIN6_LEN_RFC2133 ||
+ address->sa_family != AF_INET6)
+ return -EINVAL;
+ smk_ipv6_port_label(sock, address);
+ }
+ return 0;
+}
+#endif /* SMACK_IPV6_PORT_LABELING */
+
+/**
+ * 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;
+ if (sock->sk->sk_family != PF_INET &&
+ (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6))
+ return 0;
+ if (addrlen < offsetofend(struct sockaddr, sa_family))
+ return 0;
+ if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
+ struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
+ struct smack_known *rsp = NULL;
+
+ if (addrlen < SIN6_LEN_RFC2133)
+ return 0;
+ if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
+ rsp = smack_ipv6host_label(sip);
+ if (rsp != NULL) {
+ struct socket_smack *ssp = sock->sk->sk_security;
+
+ rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
+ SMK_CONNECTING);
+ }
+#ifdef SMACK_IPV6_PORT_LABELING
+ rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
+#endif
+
+ return rc;
+ }
+ if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
+ return 0;
+ rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
+ 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 **blob = smack_msg_msg(msg);
+
+ *blob = smk_of_current();
+ return 0;
+}
+
+/**
+ * smack_of_ipc - the smack pointer for the ipc
+ * @isp: the object
+ *
+ * Returns a pointer to the smack value
+ */
+static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
+{
+ struct smack_known **blob = smack_ipc(isp);
+
+ return *blob;
+}
+
+/**
+ * smack_ipc_alloc_security - Set the security blob for ipc
+ * @isp: the object
+ *
+ * Returns 0
+ */
+static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
+{
+ struct smack_known **blob = smack_ipc(isp);
+
+ *blob = smk_of_current();
+ return 0;
+}
+
+/**
+ * smk_curacc_shm : check if current has access on shm
+ * @isp : the object
+ * @access : access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
+{
+ struct smack_known *ssp = smack_of_ipc(isp);
+ struct smk_audit_info ad;
+ int rc;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
+ ad.a.u.ipc_id = isp->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
+ * @isp: the object
+ * @shmflg: access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
+{
+ int may;
+
+ may = smack_flags_to_may(shmflg);
+ return smk_curacc_shm(isp, may);
+}
+
+/**
+ * smack_shm_shmctl - Smack access check for shm
+ * @isp: 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 kern_ipc_perm *isp, int cmd)
+{
+ int may;
+
+ switch (cmd) {
+ case IPC_STAT:
+ case SHM_STAT:
+ case SHM_STAT_ANY:
+ 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(isp, may);
+}
+
+/**
+ * smack_shm_shmat - Smack access for shmat
+ * @isp: the object
+ * @shmaddr: unused
+ * @shmflg: access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr,
+ int shmflg)
+{
+ int may;
+
+ may = smack_flags_to_may(shmflg);
+ return smk_curacc_shm(isp, may);
+}
+
+/**
+ * smk_curacc_sem : check if current has access on sem
+ * @isp : the object
+ * @access : access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
+{
+ struct smack_known *ssp = smack_of_ipc(isp);
+ struct smk_audit_info ad;
+ int rc;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
+ ad.a.u.ipc_id = isp->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
+ * @isp: the object
+ * @semflg: access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
+{
+ int may;
+
+ may = smack_flags_to_may(semflg);
+ return smk_curacc_sem(isp, may);
+}
+
+/**
+ * smack_sem_semctl - Smack access check for sem
+ * @isp: 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 kern_ipc_perm *isp, int cmd)
+{
+ int may;
+
+ switch (cmd) {
+ case GETPID:
+ case GETNCNT:
+ case GETZCNT:
+ case GETVAL:
+ case GETALL:
+ case IPC_STAT:
+ case SEM_STAT:
+ case SEM_STAT_ANY:
+ 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(isp, may);
+}
+
+/**
+ * smack_sem_semop - Smack checks of semaphore operations
+ * @isp: 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 kern_ipc_perm *isp, struct sembuf *sops,
+ unsigned nsops, int alter)
+{
+ return smk_curacc_sem(isp, MAY_READWRITE);
+}
+
+/**
+ * smk_curacc_msq : helper to check if current has access on msq
+ * @isp : the msq
+ * @access : access requested
+ *
+ * return 0 if current has access, error otherwise
+ */
+static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
+{
+ struct smack_known *msp = smack_of_ipc(isp);
+ struct smk_audit_info ad;
+ int rc;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
+ ad.a.u.ipc_id = isp->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
+ * @isp: the object
+ * @msqflg: access requested
+ *
+ * Returns 0 if current has the requested access, error code otherwise
+ */
+static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
+{
+ int may;
+
+ may = smack_flags_to_may(msqflg);
+ return smk_curacc_msq(isp, may);
+}
+
+/**
+ * smack_msg_queue_msgctl - Smack access check for msg_queue
+ * @isp: 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 kern_ipc_perm *isp, int cmd)
+{
+ int may;
+
+ switch (cmd) {
+ case IPC_STAT:
+ case MSG_STAT:
+ case MSG_STAT_ANY:
+ 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(isp, may);
+}
+
+/**
+ * smack_msg_queue_msgsnd - Smack access check for msg_queue
+ * @isp: 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 kern_ipc_perm *isp, struct msg_msg *msg,
+ int msqflg)
+{
+ int may;
+
+ may = smack_flags_to_may(msqflg);
+ return smk_curacc_msq(isp, may);
+}
+
+/**
+ * smack_msg_queue_msgrcv - Smack access check for msg_queue
+ * @isp: 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 kern_ipc_perm *isp,
+ struct msg_msg *msg,
+ struct task_struct *target, long type,
+ int mode)
+{
+ return smk_curacc_msq(isp, 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 **blob = smack_ipc(ipp);
+ struct smack_known *iskp = *blob;
+ 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 **blob = smack_ipc(ipp);
+ struct smack_known *iskp = *blob;
+
+ *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 = smack_inode(inode);
+
+ /*
+ * If the inode is already instantiated
+ * take the quick way out
+ */
+ if (isp->smk_flags & SMK_INODE_INSTANT)
+ return;
+
+ sbp = inode->i_sb;
+ sbsp = smack_superblock(sbp);
+ /*
+ * 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) {
+ switch (sbp->s_magic) {
+ case CGROUP_SUPER_MAGIC:
+ case CGROUP2_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;
+ break;
+ case TMPFS_MAGIC:
+ /*
+ * What about shmem/tmpfs anonymous files with dentry
+ * obtained from d_alloc_pseudo()?
+ */
+ isp->smk_inode = smk_of_current();
+ break;
+ case PIPEFS_MAGIC:
+ isp->smk_inode = smk_of_current();
+ break;
+ case SOCKFS_MAGIC:
+ /*
+ * Socket access is controlled by the socket
+ * structures associated with the task involved.
+ */
+ isp->smk_inode = &smack_known_star;
+ break;
+ default:
+ isp->smk_inode = sbsp->smk_root;
+ break;
+ }
+ isp->smk_flags |= SMK_INODE_INSTANT;
+ return;
+ }
+
+ /*
+ * 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 CGROUP_SUPER_MAGIC:
+ case CGROUP2_SUPER_MAGIC:
+ /*
+ * Casey says that it's a little embarrassing
+ * that the smack file system doesn't do
+ * extended attributes.
+ *
+ * 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;
+ /*
+ * 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.
+ */
+ fallthrough;
+ 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_opflags & IOP_XATTR))
+ break;
+ /*
+ * Get the dentry for xattr.
+ */
+ dp = dget(opt_dentry);
+ skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
+ if (!IS_ERR_OR_NULL(skp))
+ 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 = __vfs_setxattr(&init_user_ns, dp, inode,
+ XATTR_NAME_SMACKTRANSMUTE,
+ TRANS_TRUE, TRANS_TRUE_SIZE,
+ 0);
+ } else {
+ rc = __vfs_getxattr(dp, inode,
+ 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 (IS_ERR(skp) || skp == &smack_known_star ||
+ skp == &smack_known_web)
+ skp = NULL;
+ isp->smk_task = skp;
+
+ skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
+ if (IS_ERR(skp) || 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);
+
+ 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, const char *name, char **value)
+{
+ struct smack_known *skp = smk_of_task_struct_obj(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
+ * @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(const char *name, void *value, size_t size)
+{
+ struct task_smack *tsp = smack_cred(current_cred());
+ struct cred *new;
+ struct smack_known *skp;
+ struct smack_known_list_elem *sklep;
+ int rc;
+
+ if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
+ 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 (IS_ERR(skp))
+ return PTR_ERR(skp);
+
+ /*
+ * No process is ever allowed the web ("@") label
+ * and the star ("*") label.
+ */
+ if (skp == &smack_known_web || skp == &smack_known_star)
+ return -EINVAL;
+
+ if (!smack_privileged(CAP_MAC_ADMIN)) {
+ rc = -EPERM;
+ list_for_each_entry(sklep, &tsp->smk_relabel, list)
+ if (sklep->smk_label == skp) {
+ rc = 0;
+ break;
+ }
+ if (rc)
+ return rc;
+ }
+
+ new = prepare_creds();
+ if (new == NULL)
+ return -ENOMEM;
+
+ tsp = smack_cred(new);
+ tsp->smk_task = skp;
+ /*
+ * process can change its label only once
+ */
+ smk_destroy_label_list(&tsp->smk_relabel);
+
+ 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_in;
+#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) {
+ okp = osp->smk_out;
+ skp = ssp->smk_in;
+ rc = smk_access(okp, skp, MAY_WRITE, &ad);
+ 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;
+#if IS_ENABLED(CONFIG_IPV6)
+ struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
+#endif
+#ifdef SMACK_IPV6_SECMARK_LABELING
+ struct socket_smack *ssp = sock->sk->sk_security;
+ struct smack_known *rsp;
+#endif
+ int rc = 0;
+
+ /*
+ * Perfectly reasonable for this to be NULL
+ */
+ if (sip == NULL)
+ return 0;
+
+ switch (sock->sk->sk_family) {
+ case AF_INET:
+ if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
+ sip->sin_family != AF_INET)
+ return -EINVAL;
+ rc = smk_ipv4_check(sock->sk, sip);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case AF_INET6:
+ if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
+ sap->sin6_family != AF_INET6)
+ return -EINVAL;
+#ifdef SMACK_IPV6_SECMARK_LABELING
+ rsp = smack_ipv6host_label(sap);
+ if (rsp != NULL)
+ rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
+ SMK_CONNECTING);
+#endif
+#ifdef SMACK_IPV6_PORT_LABELING
+ rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
+#endif
+#endif /* IS_ENABLED(CONFIG_IPV6) */
+ 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;
+
+ /*
+ * Netlabel found it in the cache.
+ */
+ if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
+ return (struct smack_known *)sap->cache->data;
+
+ if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
+ /*
+ * Looks like a fallback, which gives us a secid.
+ */
+ return smack_from_secid(sap->attr.secid);
+
+ 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_rcu(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;
+ }
+ /*
+ * Without guidance regarding the smack value
+ * for the packet fall back on the network
+ * ambient value.
+ */
+ return smack_net_ambient;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+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:
+ case IPPROTO_UDPLITE:
+ 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;
+}
+#endif /* CONFIG_IPV6 */
+
+/**
+ * smack_from_skb - Smack data from the secmark in an skb
+ * @skb: packet
+ *
+ * Returns smack_known of the secmark or NULL if that won't work.
+ */
+#ifdef CONFIG_NETWORK_SECMARK
+static struct smack_known *smack_from_skb(struct sk_buff *skb)
+{
+ if (skb == NULL || skb->secmark == 0)
+ return NULL;
+
+ return smack_from_secid(skb->secmark);
+}
+#else
+static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
+{
+ return NULL;
+}
+#endif
+
+/**
+ * smack_from_netlbl - Smack data from the IP options in an skb
+ * @sk: socket data came in on
+ * @family: address family
+ * @skb: packet
+ *
+ * Find the Smack label in the IP options. If it hasn't been
+ * added to the netlabel cache, add it here.
+ *
+ * Returns smack_known of the IP options or NULL if that won't work.
+ */
+static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
+ struct sk_buff *skb)
+{
+ struct netlbl_lsm_secattr secattr;
+ struct socket_smack *ssp = NULL;
+ struct smack_known *skp = NULL;
+
+ netlbl_secattr_init(&secattr);
+
+ if (sk)
+ ssp = sk->sk_security;
+
+ if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
+ skp = smack_from_secattr(&secattr, ssp);
+ if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
+ netlbl_cache_add(skb, family, &skp->smk_netlabel);
+ }
+
+ netlbl_secattr_destroy(&secattr);
+
+ return skp;
+}
+
+/**
+ * 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 socket_smack *ssp = sk->sk_security;
+ struct smack_known *skp = NULL;
+ int rc = 0;
+ struct smk_audit_info ad;
+ u16 family = sk->sk_family;
+#ifdef CONFIG_AUDIT
+ struct lsm_network_audit net;
+#endif
+#if IS_ENABLED(CONFIG_IPV6)
+ struct sockaddr_in6 sadd;
+ int proto;
+
+ if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+ family = PF_INET;
+#endif /* CONFIG_IPV6 */
+
+ switch (family) {
+ case PF_INET:
+ /*
+ * If there is a secmark use it rather than the CIPSO label.
+ * If there is no secmark fall back to CIPSO.
+ * The secmark is assumed to reflect policy better.
+ */
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp == NULL)
+ skp = smack_net_ambient;
+ }
+
+#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.
+ * 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, family, rc, 0);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case PF_INET6:
+ proto = smk_skb_to_addr_ipv6(skb, &sadd);
+ if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE &&
+ proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
+ break;
+#ifdef SMACK_IPV6_SECMARK_LABELING
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ if (smk_ipv6_localhost(&sadd))
+ break;
+ skp = smack_ipv6host_label(&sadd);
+ if (skp == NULL)
+ skp = smack_net_ambient;
+ }
+#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;
+ ipv6_skb_to_auditdata(skb, &ad.a, NULL);
+#endif /* CONFIG_AUDIT */
+ rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
+ rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
+ MAY_WRITE, rc);
+#endif /* SMACK_IPV6_SECMARK_LABELING */
+#ifdef SMACK_IPV6_PORT_LABELING
+ rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
+#endif /* SMACK_IPV6_PORT_LABELING */
+ if (rc != 0)
+ icmpv6_send(skb, ICMPV6_DEST_UNREACH,
+ ICMPV6_ADM_PROHIBITED, 0);
+ break;
+#endif /* CONFIG_IPV6 */
+ }
+
+ 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 socket_smack *ssp = NULL;
+ struct smack_known *skp;
+ struct sock *sk = NULL;
+ int family = PF_UNSPEC;
+ u32 s = 0; /* 0 is the invalid secid */
+
+ if (skb != NULL) {
+ if (skb->protocol == htons(ETH_P_IP))
+ family = PF_INET;
+#if IS_ENABLED(CONFIG_IPV6)
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ family = PF_INET6;
+#endif /* CONFIG_IPV6 */
+ }
+ if (family == PF_UNSPEC && sock != NULL)
+ family = sock->sk->sk_family;
+
+ switch (family) {
+ case PF_UNIX:
+ ssp = sock->sk->sk_security;
+ s = ssp->smk_out->smk_secid;
+ break;
+ case PF_INET:
+ skp = smack_from_skb(skb);
+ if (skp) {
+ s = skp->smk_secid;
+ break;
+ }
+ /*
+ * Translate what netlabel gave us.
+ */
+ if (sock != NULL)
+ sk = sock->sk;
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp != NULL)
+ s = skp->smk_secid;
+ break;
+ case PF_INET6:
+#ifdef SMACK_IPV6_SECMARK_LABELING
+ skp = smack_from_skb(skb);
+ if (skp)
+ s = skp->smk_secid;
+#endif
+ break;
+ }
+ *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(const 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 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 IS_ENABLED(CONFIG_IPV6)
+ 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;
+ }
+#endif /* CONFIG_IPV6 */
+
+ /*
+ * If there is a secmark use it rather than the CIPSO label.
+ * If there is no secmark fall back to CIPSO.
+ * The secmark is assumed to reflect policy better.
+ */
+ skp = smack_from_skb(skb);
+ if (skp == NULL) {
+ skp = smack_from_netlbl(sk, family, skb);
+ if (skp == NULL)
+ skp = &smack_known_huh;
+ }
+
+#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_ipv4host_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(smack_cred(cred));
+
+ 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
+ * @need_perm: requested key permission
+ *
+ * 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,
+ enum key_need_perm need_perm)
+{
+ struct key *keyp;
+ struct smk_audit_info ad;
+ struct smack_known *tkp = smk_of_task(smack_cred(cred));
+ int request = 0;
+ int rc;
+
+ /*
+ * Validate requested permissions
+ */
+ switch (need_perm) {
+ case KEY_NEED_READ:
+ case KEY_NEED_SEARCH:
+ case KEY_NEED_VIEW:
+ request |= MAY_READ;
+ break;
+ case KEY_NEED_WRITE:
+ case KEY_NEED_LINK:
+ case KEY_NEED_SETATTR:
+ request |= MAY_WRITE;
+ break;
+ case KEY_NEED_UNSPECIFIED:
+ case KEY_NEED_UNLINK:
+ case KEY_SYSADMIN_OVERRIDE:
+ case KEY_AUTHTOKEN_OVERRIDE:
+ case KEY_DEFER_PERM_CHECK:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+
+ 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;
+
+ if (smack_privileged(CAP_MAC_OVERRIDE))
+ return 0;
+
+#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
+ rc = smk_access(tkp, keyp->security, request, &ad);
+ rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
+ return rc;
+}
+
+/*
+ * smack_key_getsecurity - Smack label tagging the key
+ * @key points to the key to be queried
+ * @_buffer points to a pointer that should be set to point to the
+ * resulting string (if no label or an error occurs).
+ * Return the length of the string (including terminating NUL) or -ve if
+ * an error.
+ * May also return 0 (and a NULL buffer pointer) if there is no label.
+ */
+static int smack_key_getsecurity(struct key *key, char **_buffer)
+{
+ struct smack_known *skp = key->security;
+ size_t length;
+ char *copy;
+
+ if (key->security == NULL) {
+ *_buffer = NULL;
+ return 0;
+ }
+
+ copy = kstrdup(skp->smk_known, GFP_KERNEL);
+ if (copy == NULL)
+ return -ENOMEM;
+ length = strlen(copy) + 1;
+
+ *_buffer = copy;
+ return length;
+}
+
+
+#ifdef CONFIG_KEY_NOTIFICATIONS
+/**
+ * smack_watch_key - Smack access to watch a key for notifications.
+ * @key: The key to be watched
+ *
+ * Return 0 if the @watch->cred has permission to read from the key object and
+ * an error otherwise.
+ */
+static int smack_watch_key(struct key *key)
+{
+ struct smk_audit_info ad;
+ struct smack_known *tkp = smk_of_current();
+ int rc;
+
+ if (key == NULL)
+ return -EINVAL;
+ /*
+ * If the key hasn't been initialized give it access so that
+ * it may do so.
+ */
+ if (key->security == NULL)
+ return 0;
+ /*
+ * This should not occur
+ */
+ if (tkp == NULL)
+ return -EACCES;
+
+ if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
+ return 0;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
+ ad.a.u.key_struct.key = key->serial;
+ ad.a.u.key_struct.key_desc = key->description;
+#endif
+ rc = smk_access(tkp, key->security, MAY_READ, &ad);
+ rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
+ return rc;
+}
+#endif /* CONFIG_KEY_NOTIFICATIONS */
+#endif /* CONFIG_KEYS */
+
+#ifdef CONFIG_WATCH_QUEUE
+/**
+ * smack_post_notification - Smack access to post a notification to a queue
+ * @w_cred: The credentials of the watcher.
+ * @cred: The credentials of the event source (may be NULL).
+ * @n: The notification message to be posted.
+ */
+static int smack_post_notification(const struct cred *w_cred,
+ const struct cred *cred,
+ struct watch_notification *n)
+{
+ struct smk_audit_info ad;
+ struct smack_known *subj, *obj;
+ int rc;
+
+ /* Always let maintenance notifications through. */
+ if (n->type == WATCH_TYPE_META)
+ return 0;
+
+ if (!cred)
+ return 0;
+ subj = smk_of_task(smack_cred(cred));
+ obj = smk_of_task(smack_cred(w_cred));
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
+ rc = smk_access(subj, obj, MAY_WRITE, &ad);
+ rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
+ return rc;
+}
+#endif /* CONFIG_WATCH_QUEUE */
+
+/*
+ * 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 (IS_ERR(skp))
+ return PTR_ERR(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
+ *
+ * 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 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;
+}
+
+/*
+ * There is no need for a smack_audit_rule_free hook.
+ * No memory was allocated.
+ */
+
+#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;
+}
+
+/*
+ * There used to be a smack_release_secctx hook
+ * that did nothing back when hooks were in a vector.
+ * Now that there's a list such a hook adds cost.
+ */
+
+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(&init_user_ns, dentry, XATTR_NAME_SMACK,
+ ctx, ctxlen, 0);
+}
+
+static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+{
+ struct smack_known *skp = smk_of_inode(inode);
+
+ *ctx = skp->smk_known;
+ *ctxlen = strlen(skp->smk_known);
+ return 0;
+}
+
+static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
+{
+
+ struct task_smack *tsp;
+ struct smack_known *skp;
+ struct inode_smack *isp;
+ struct cred *new_creds = *new;
+
+ if (new_creds == NULL) {
+ new_creds = prepare_creds();
+ if (new_creds == NULL)
+ return -ENOMEM;
+ }
+
+ tsp = smack_cred(new_creds);
+
+ /*
+ * Get label from overlay inode and set it in create_sid
+ */
+ isp = smack_inode(d_inode(dentry));
+ skp = isp->smk_inode;
+ tsp->smk_task = skp;
+ *new = new_creds;
+ return 0;
+}
+
+static int smack_inode_copy_up_xattr(const char *name)
+{
+ /*
+ * Return 1 if this is the smack access Smack attribute.
+ */
+ if (strcmp(name, XATTR_NAME_SMACK) == 0)
+ return 1;
+
+ return -EOPNOTSUPP;
+}
+
+static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
+ struct qstr *name,
+ const struct cred *old,
+ struct cred *new)
+{
+ struct task_smack *otsp = smack_cred(old);
+ struct task_smack *ntsp = smack_cred(new);
+ struct inode_smack *isp;
+ int may;
+
+ /*
+ * Use the process credential unless all of
+ * the transmuting criteria are met
+ */
+ ntsp->smk_task = otsp->smk_task;
+
+ /*
+ * the attribute of the containing directory
+ */
+ isp = smack_inode(d_inode(dentry->d_parent));
+
+ if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
+ rcu_read_lock();
+ may = smk_access_entry(otsp->smk_task->smk_known,
+ isp->smk_inode->smk_known,
+ &otsp->smk_task->smk_rules);
+ rcu_read_unlock();
+
+ /*
+ * If the directory is transmuting and the rule
+ * providing access is transmuting use the containing
+ * directory label instead of the process label.
+ */
+ if (may > 0 && (may & MAY_TRANSMUTE)) {
+ ntsp->smk_task = isp->smk_inode;
+ ntsp->smk_transmuted = ntsp->smk_task;
+ }
+ }
+ return 0;
+}
+
+#ifdef CONFIG_IO_URING
+/**
+ * smack_uring_override_creds - Is io_uring cred override allowed?
+ * @new: the target creds
+ *
+ * Check to see if the current task is allowed to override it's credentials
+ * to service an io_uring operation.
+ */
+static int smack_uring_override_creds(const struct cred *new)
+{
+ struct task_smack *tsp = smack_cred(current_cred());
+ struct task_smack *nsp = smack_cred(new);
+
+ /*
+ * Allow the degenerate case where the new Smack value is
+ * the same as the current Smack value.
+ */
+ if (tsp->smk_task == nsp->smk_task)
+ return 0;
+
+ if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
+ return 0;
+
+ return -EPERM;
+}
+
+/**
+ * smack_uring_sqpoll - check if a io_uring polling thread can be created
+ *
+ * Check to see if the current task is allowed to create a new io_uring
+ * kernel polling thread.
+ */
+static int smack_uring_sqpoll(void)
+{
+ if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
+ return 0;
+
+ return -EPERM;
+}
+
+/**
+ * smack_uring_cmd - check on file operations for io_uring
+ * @ioucmd: the command in question
+ *
+ * Make a best guess about whether a io_uring "command" should
+ * be allowed. Use the same logic used for determining if the
+ * file could be opened for read in the absence of better criteria.
+ */
+static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
+{
+ struct file *file = ioucmd->file;
+ struct smk_audit_info ad;
+ struct task_smack *tsp;
+ struct inode *inode;
+ int rc;
+
+ if (!file)
+ return -EINVAL;
+
+ tsp = smack_cred(file->f_cred);
+ inode = file_inode(file);
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
+ smk_ad_setfield_u_fs_path(&ad, file->f_path);
+ rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
+ rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
+
+ return rc;
+}
+
+#endif /* CONFIG_IO_URING */
+
+struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct task_smack),
+ .lbs_file = sizeof(struct smack_known *),
+ .lbs_inode = sizeof(struct inode_smack),
+ .lbs_ipc = sizeof(struct smack_known *),
+ .lbs_msg_msg = sizeof(struct smack_known *),
+ .lbs_superblock = sizeof(struct superblock_smack),
+};
+
+static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
+ LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
+ LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
+ LSM_HOOK_INIT(syslog, smack_syslog),
+
+ LSM_HOOK_INIT(fs_context_submount, smack_fs_context_submount),
+ LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
+ LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
+
+ LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
+ LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
+ LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
+ LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
+ LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
+
+ LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
+
+ LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
+ LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
+ LSM_HOOK_INIT(inode_link, smack_inode_link),
+ LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
+ LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
+ LSM_HOOK_INIT(inode_rename, smack_inode_rename),
+ LSM_HOOK_INIT(inode_permission, smack_inode_permission),
+ LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
+ LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
+ LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
+ LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
+ LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
+ LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
+ LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
+ LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
+ LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
+ LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
+
+ LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
+ LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
+ LSM_HOOK_INIT(file_ioctl_compat, smack_file_ioctl),
+ LSM_HOOK_INIT(file_lock, smack_file_lock),
+ LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
+ LSM_HOOK_INIT(mmap_file, smack_mmap_file),
+ LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
+ LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
+ LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
+ LSM_HOOK_INIT(file_receive, smack_file_receive),
+
+ LSM_HOOK_INIT(file_open, smack_file_open),
+
+ LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
+ LSM_HOOK_INIT(cred_free, smack_cred_free),
+ LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
+ LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
+ LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
+ LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
+ LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
+ LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
+ LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
+ LSM_HOOK_INIT(task_getsid, smack_task_getsid),
+ LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj),
+ LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj),
+ LSM_HOOK_INIT(task_setnice, smack_task_setnice),
+ LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
+ LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
+ LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
+ LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
+ LSM_HOOK_INIT(task_movememory, smack_task_movememory),
+ LSM_HOOK_INIT(task_kill, smack_task_kill),
+ LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
+
+ LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
+ LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
+
+ LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
+
+ LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
+ LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
+ LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
+ LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
+ LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
+
+ LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
+ LSM_HOOK_INIT(shm_associate, smack_shm_associate),
+ LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
+ LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
+
+ LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
+ LSM_HOOK_INIT(sem_associate, smack_sem_associate),
+ LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
+ LSM_HOOK_INIT(sem_semop, smack_sem_semop),
+
+ LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
+
+ LSM_HOOK_INIT(getprocattr, smack_getprocattr),
+ LSM_HOOK_INIT(setprocattr, smack_setprocattr),
+
+ LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
+ LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
+
+ LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
+ LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair),
+#ifdef SMACK_IPV6_PORT_LABELING
+ LSM_HOOK_INIT(socket_bind, smack_socket_bind),
+#endif
+ LSM_HOOK_INIT(socket_connect, smack_socket_connect),
+ LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
+ LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
+ LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
+ LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
+ LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
+ LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
+ LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security),
+ LSM_HOOK_INIT(sock_graft, smack_sock_graft),
+ LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
+ LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
+
+ /* key management security hooks */
+#ifdef CONFIG_KEYS
+ LSM_HOOK_INIT(key_alloc, smack_key_alloc),
+ LSM_HOOK_INIT(key_free, smack_key_free),
+ LSM_HOOK_INIT(key_permission, smack_key_permission),
+ LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
+#ifdef CONFIG_KEY_NOTIFICATIONS
+ LSM_HOOK_INIT(watch_key, smack_watch_key),
+#endif
+#endif /* CONFIG_KEYS */
+
+#ifdef CONFIG_WATCH_QUEUE
+ LSM_HOOK_INIT(post_notification, smack_post_notification),
+#endif
+
+ /* Audit hooks */
+#ifdef CONFIG_AUDIT
+ LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
+ LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
+ LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
+#endif /* CONFIG_AUDIT */
+
+ LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
+ LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
+ LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
+ LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
+ LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
+ LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
+ LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
+ LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
+ LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
+#ifdef CONFIG_IO_URING
+ LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
+ LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
+ LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
+#endif
+};
+
+
+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_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_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_web);
+}
+
+/**
+ * smack_init - initialize the smack system
+ *
+ * Returns 0 on success, -ENOMEM is there's no memory
+ */
+static __init int smack_init(void)
+{
+ struct cred *cred = (struct cred *) current->cred;
+ struct task_smack *tsp;
+
+ smack_rule_cache = KMEM_CACHE(smack_rule, 0);
+ if (!smack_rule_cache)
+ return -ENOMEM;
+
+ /*
+ * Set the security state for the initial task.
+ */
+ tsp = smack_cred(cred);
+ init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
+
+ /*
+ * Register with LSM
+ */
+ security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
+ smack_enabled = 1;
+
+ pr_info("Smack: Initializing.\n");
+#ifdef CONFIG_SECURITY_SMACK_NETFILTER
+ pr_info("Smack: Netfilter enabled.\n");
+#endif
+#ifdef SMACK_IPV6_PORT_LABELING
+ pr_info("Smack: IPv6 port labeling enabled.\n");
+#endif
+#ifdef SMACK_IPV6_SECMARK_LABELING
+ pr_info("Smack: IPv6 Netfilter enabled.\n");
+#endif
+
+ /* initialize the smack_known_list */
+ init_smack_known_list();
+
+ return 0;
+}
+
+/*
+ * Smack requires early initialization in order to label
+ * all processes and objects when they are created.
+ */
+DEFINE_LSM(smack) = {
+ .name = "smack",
+ .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+ .blobs = &smack_blob_sizes,
+ .init = smack_init,
+};