| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Casey Schaufler | 11722 | 63.19% | 80 | 28.07% |
| Etienne Basset | 1194 | 6.44% | 4 | 1.40% |
| David Howells | 1008 | 5.43% | 19 | 6.67% |
| Al Viro | 607 | 3.27% | 22 | 7.72% |
| Lukasz Pawelczyk | 562 | 3.03% | 9 | 3.16% |
| Paul Moore | 393 | 2.12% | 13 | 4.56% |
| Ahmed S. Darwish | 293 | 1.58% | 2 | 0.70% |
| Christian Brauner | 293 | 1.58% | 5 | 1.75% |
| Vivek Trivedi | 249 | 1.34% | 1 | 0.35% |
| Jarkko Sakkinen | 220 | 1.19% | 4 | 1.40% |
| Roberto Sassu | 219 | 1.18% | 4 | 1.40% |
| Zbigniew Jasinski | 200 | 1.08% | 2 | 0.70% |
| José Bollo | 163 | 0.88% | 6 | 2.11% |
| Vishal Goel | 148 | 0.80% | 4 | 1.40% |
| David P. Quigley | 124 | 0.67% | 3 | 1.05% |
| Seth Forshee | 98 | 0.53% | 2 | 0.70% |
| Eric Paris | 88 | 0.47% | 10 | 3.51% |
| Himanshu Shukla | 83 | 0.45% | 3 | 1.05% |
| Eric W. Biedermann | 71 | 0.38% | 6 | 2.11% |
| Kees Cook | 70 | 0.38% | 6 | 2.11% |
| Seung-Woo Kim | 68 | 0.37% | 2 | 0.70% |
| Tetsuo Handa | 63 | 0.34% | 3 | 1.05% |
| Tom Gundersen | 59 | 0.32% | 1 | 0.35% |
| Piotr Sawicki | 55 | 0.30% | 3 | 1.05% |
| Marcin Lis | 50 | 0.27% | 1 | 0.35% |
| Lontke Michael | 49 | 0.26% | 1 | 0.35% |
| Matthew Garrett | 40 | 0.22% | 1 | 0.35% |
| Rafal Krypa | 32 | 0.17% | 4 | 1.40% |
| jooseong lee | 31 | 0.17% | 1 | 0.35% |
| Stephen D. Smalley | 30 | 0.16% | 5 | 1.75% |
| Łukasz Stelmach | 28 | 0.15% | 1 | 0.35% |
| Andrey Ryabinin | 16 | 0.09% | 1 | 0.35% |
| Jann Horn | 15 | 0.08% | 2 | 0.70% |
| luanshi | 15 | 0.08% | 1 | 0.35% |
| Andreas Gruenbacher | 15 | 0.08% | 2 | 0.70% |
| Roman Kubiak | 15 | 0.08% | 2 | 0.70% |
| Linus Torvalds | 14 | 0.08% | 4 | 1.40% |
| Rohit kumar | 13 | 0.07% | 1 | 0.35% |
| Davidlohr Bueso A | 9 | 0.05% | 3 | 1.05% |
| Arnd Bergmann | 9 | 0.05% | 1 | 0.35% |
| Andrew Morton | 8 | 0.04% | 3 | 1.05% |
| Andi Kleen | 8 | 0.04% | 1 | 0.35% |
| Igor Zhbanov | 8 | 0.04% | 1 | 0.35% |
| Sebastian Andrzej Siewior | 8 | 0.04% | 1 | 0.35% |
| Randy Dunlap | 8 | 0.04% | 1 | 0.35% |
| Zoran Markovic | 7 | 0.04% | 1 | 0.35% |
| Linus Torvalds (pre-git) | 7 | 0.04% | 3 | 1.05% |
| Dmitry Kasatkin | 6 | 0.03% | 1 | 0.35% |
| Richard Guy Briggs | 6 | 0.03% | 2 | 0.70% |
| Venkat Yekkirala | 6 | 0.03% | 2 | 0.70% |
| Konstantin Khlebnikov | 5 | 0.03% | 2 | 0.70% |
| Tomasz Stanislawski | 5 | 0.03% | 1 | 0.35% |
| Vasyl Gomonovych | 4 | 0.02% | 1 | 0.35% |
| Ingo Molnar | 3 | 0.02% | 1 | 0.35% |
| Pankaj Kumar | 3 | 0.02% | 1 | 0.35% |
| Nick Black | 3 | 0.02% | 1 | 0.35% |
| Gustavo A. R. Silva | 3 | 0.02% | 2 | 0.70% |
| David S. Miller | 3 | 0.02% | 1 | 0.35% |
| Thomas Gleixner | 2 | 0.01% | 1 | 0.35% |
| Tycho Andersen | 2 | 0.01% | 1 | 0.35% |
| Eric Dumazet | 2 | 0.01% | 1 | 0.35% |
| James Morris | 2 | 0.01% | 1 | 0.35% |
| Florian Westphal | 2 | 0.01% | 1 | 0.35% |
| xupanda | 1 | 0.01% | 1 | 0.35% |
| Eric Biggers | 1 | 0.01% | 1 | 0.35% |
| Jeff Layton | 1 | 0.01% | 1 | 0.35% |
| Geliang Tang | 1 | 0.01% | 1 | 0.35% |
| Huw Davies | 1 | 0.01% | 1 | 0.35% |
| Dan Carpenter | 1 | 0.01% | 1 | 0.35% |
| Austin Kim | 1 | 0.01% | 1 | 0.35% |
| Oliver Neukum | 1 | 0.01% | 1 | 0.35% |
| Lucas De Marchi | 1 | 0.01% | 1 | 0.35% |
| Total | 18551 | 285 |
// 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 /* * Smack uses multiple xattrs. * SMACK64 - for access control, * SMACK64TRANSMUTE - label initialization, * Not saved on files - SMACK64IPIN and SMACK64IPOUT, * Must be set explicitly - SMACK64EXEC and SMACK64MMAP */ #define SMACK_INODE_INIT_XATTRS 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; const char *fsfloor; const char *fshat; const char *fsroot; const char *fstransmute; }; static void smack_free_mnt_opts(void *mnt_opts) { kfree(mnt_opts); } static int smack_add_opt(int token, const char *s, void **mnt_opts) { struct smack_mnt_opts *opts = *mnt_opts; struct smack_known *skp; if (!opts) { opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL); if (!opts) return -ENOMEM; *mnt_opts = opts; } if (!s) return -ENOMEM; skp = smk_import_entry(s, 0); if (IS_ERR(skp)) return PTR_ERR(skp); switch (token) { case Opt_fsdefault: if (opts->fsdefault) goto out_opt_err; opts->fsdefault = skp->smk_known; break; case Opt_fsfloor: if (opts->fsfloor) goto out_opt_err; opts->fsfloor = skp->smk_known; break; case Opt_fshat: if (opts->fshat) goto out_opt_err; opts->fshat = skp->smk_known; break; case Opt_fsroot: if (opts->fsroot) goto out_opt_err; opts->fsroot = skp->smk_known; break; case Opt_fstransmute: if (opts->fstransmute) goto out_opt_err; opts->fstransmute = skp->smk_known; 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; dst->fsdefault = src->fsdefault; dst->fsfloor = src->fsfloor; dst->fshat = src->fshat; dst->fsroot = src->fsroot; dst->fstransmute = src->fstransmute; 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); kfree(arg); if (unlikely(rc)) { 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 * @xattrs: where to put the attributes * @xattr_count: current number of LSM-provided xattrs (updated) * * 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, struct xattr *xattrs, int *xattr_count) { struct task_smack *tsp = smack_cred(current_cred()); struct smack_known *skp = smk_of_task(tsp); struct smack_known *isp = smk_of_inode(inode); struct smack_known *dsp = smk_of_inode(dir); struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); int may; if (xattr) { /* * 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))) { struct xattr *xattr_transmute; /* * 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; xattr_transmute = lsm_get_xattr_slot(xattrs, xattr_count); if (xattr_transmute) { xattr_transmute->value = kmemdup(TRANS_TRUE, TRANS_TRUE_SIZE, GFP_NOFS); if (!xattr_transmute->value) return -ENOMEM; xattr_transmute->value_len = TRANS_TRUE_SIZE; xattr_transmute->name = XATTR_SMACK_TRANSMUTE; } } xattr->value = kstrdup(isp->smk_known, GFP_NOFS); if (!xattr->value) return -ENOMEM; xattr->value_len = strlen(isp->smk_known); xattr->name = XATTR_SMACK_SUFFIX; } 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 * @idmap: idmap of the mount * @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 mnt_idmap *idmap, 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 * @idmap: idmap of the mount * @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 mnt_idmap *idmap, 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(idmap, 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_set_acl - Smack check for setting posix acls * @idmap: idmap of the mnt this request came from * @dentry: the object * @acl_name: name of the posix acl * @kacl: the posix acls * * Returns 0 if access is permitted, an error code otherwise */ static int smack_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { 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_WRITE, &ad); rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); return rc; } /** * smack_inode_get_acl - Smack check for getting posix acls * @idmap: idmap of the mnt this request came from * @dentry: the object * @acl_name: name of the posix acl * * Returns 0 if access is permitted, an error code otherwise */ static int smack_inode_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_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_remove_acl - Smack check for getting posix acls * @idmap: idmap of the mnt this request came from * @dentry: the object * @acl_name: name of the posix acl * * Returns 0 if access is permitted, an error code otherwise */ static int smack_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_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_WRITE, &ad); rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); return rc; } /** * smack_inode_getsecurity - get smack xattrs * @idmap: idmap of the mount * @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 mnt_idmap *idmap, struct inode *inode, const char *name, void **buffer, bool alloc) { struct socket_smack *ssp; struct socket *sock; struct super_block *sbp; struct inode *ip = 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. */ 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, sockptr_t optval, sockptr_t optlen, unsigned int len) { struct socket_smack *ssp; char *rcp = ""; u32 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; goto out_len; } if (copy_to_sockptr(optval, rcp, slen)) rc = -EFAULT; out_len: if (copy_to_sockptr(optlen, &slen, sizeof(slen))) 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(&nop_mnt_idmap, 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 __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), .lbs_xattr_count = SMACK_INODE_INIT_XATTRS, }; static struct security_hook_list smack_hooks[] __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_set_acl, smack_inode_set_acl), LSM_HOOK_INIT(inode_get_acl, smack_inode_get_acl), LSM_HOOK_INIT(inode_remove_acl, smack_inode_remove_acl), 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_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, };
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