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linux/security/smack/smackfs.c
Casey Schaufler 4e328b0888 Smack: Create smack_rule cache to optimize memory usage 
This patch allows for small memory optimization by creating the
kmem cache for "struct smack_rule" instead of using kzalloc.
For adding new smack rule, kzalloc is used to allocate the memory
for "struct smack_rule". kzalloc will always allocate 32 or 64 bytes
for 1 structure depending upon the kzalloc cache sizes available in
system. Although the size of structure is 20 bytes only, resulting
in memory wastage per object in the default pool.

For e.g., if there are 20000 rules, then it will save 240KB(20000*12)
which is crucial for small memory targets.

Signed-off-by: Vishal Goel <vishal.goel@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2019-04-02 11:45:41 -07:00

2991 lines
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/*
* Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*
* Authors:
* Casey Schaufler <casey@schaufler-ca.com>
* Ahmed S. Darwish <darwish.07@gmail.com>
*
* Special thanks to the authors of selinuxfs.
*
* Karl MacMillan <kmacmillan@tresys.com>
* James Morris <jmorris@redhat.com>
*
*/
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/security.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <net/net_namespace.h>
#include <net/cipso_ipv4.h>
#include <linux/seq_file.h>
#include <linux/ctype.h>
#include <linux/audit.h>
#include <linux/magic.h>
#include "smack.h"
#define BEBITS (sizeof(__be32) * 8)
/*
* smackfs pseudo filesystem.
*/
enum smk_inos {
SMK_ROOT_INO = 2,
SMK_LOAD = 3, /* load policy */
SMK_CIPSO = 4, /* load label -> CIPSO mapping */
SMK_DOI = 5, /* CIPSO DOI */
SMK_DIRECT = 6, /* CIPSO level indicating direct label */
SMK_AMBIENT = 7, /* internet ambient label */
SMK_NET4ADDR = 8, /* single label hosts */
SMK_ONLYCAP = 9, /* the only "capable" label */
SMK_LOGGING = 10, /* logging */
SMK_LOAD_SELF = 11, /* task specific rules */
SMK_ACCESSES = 12, /* access policy */
SMK_MAPPED = 13, /* CIPSO level indicating mapped label */
SMK_LOAD2 = 14, /* load policy with long labels */
SMK_LOAD_SELF2 = 15, /* load task specific rules with long labels */
SMK_ACCESS2 = 16, /* make an access check with long labels */
SMK_CIPSO2 = 17, /* load long label -> CIPSO mapping */
SMK_REVOKE_SUBJ = 18, /* set rules with subject label to '-' */
SMK_CHANGE_RULE = 19, /* change or add rules (long labels) */
SMK_SYSLOG = 20, /* change syslog label) */
SMK_PTRACE = 21, /* set ptrace rule */
#ifdef CONFIG_SECURITY_SMACK_BRINGUP
SMK_UNCONFINED = 22, /* define an unconfined label */
#endif
#if IS_ENABLED(CONFIG_IPV6)
SMK_NET6ADDR = 23, /* single label IPv6 hosts */
#endif /* CONFIG_IPV6 */
SMK_RELABEL_SELF = 24, /* relabel possible without CAP_MAC_ADMIN */
};
/*
* List locks
*/
static DEFINE_MUTEX(smack_cipso_lock);
static DEFINE_MUTEX(smack_ambient_lock);
static DEFINE_MUTEX(smk_net4addr_lock);
#if IS_ENABLED(CONFIG_IPV6)
static DEFINE_MUTEX(smk_net6addr_lock);
#endif /* CONFIG_IPV6 */
/*
* This is the "ambient" label for network traffic.
* If it isn't somehow marked, use this.
* It can be reset via smackfs/ambient
*/
struct smack_known *smack_net_ambient;
/*
* This is the level in a CIPSO header that indicates a
* smack label is contained directly in the category set.
* It can be reset via smackfs/direct
*/
int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT;
/*
* This is the level in a CIPSO header that indicates a
* secid is contained directly in the category set.
* It can be reset via smackfs/mapped
*/
int smack_cipso_mapped = SMACK_CIPSO_MAPPED_DEFAULT;
#ifdef CONFIG_SECURITY_SMACK_BRINGUP
/*
* Allow one label to be unconfined. This is for
* debugging and application bring-up purposes only.
* It is bad and wrong, but everyone seems to expect
* to have it.
*/
struct smack_known *smack_unconfined;
#endif
/*
* If this value is set restrict syslog use to the label specified.
* It can be reset via smackfs/syslog
*/
struct smack_known *smack_syslog_label;
/*
* Ptrace current rule
* SMACK_PTRACE_DEFAULT regular smack ptrace rules (/proc based)
* SMACK_PTRACE_EXACT labels must match, but can be overriden with
* CAP_SYS_PTRACE
* SMACK_PTRACE_DRACONIAN lables must match, CAP_SYS_PTRACE has no effect
*/
int smack_ptrace_rule = SMACK_PTRACE_DEFAULT;
/*
* Certain IP addresses may be designated as single label hosts.
* Packets are sent there unlabeled, but only from tasks that
* can write to the specified label.
*/
LIST_HEAD(smk_net4addr_list);
#if IS_ENABLED(CONFIG_IPV6)
LIST_HEAD(smk_net6addr_list);
#endif /* CONFIG_IPV6 */
/*
* Rule lists are maintained for each label.
*/
struct smack_parsed_rule {
struct smack_known *smk_subject;
struct smack_known *smk_object;
int smk_access1;
int smk_access2;
};
static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
/*
* Values for parsing cipso rules
* SMK_DIGITLEN: Length of a digit field in a rule.
* SMK_CIPSOMIN: Minimum possible cipso rule length.
* SMK_CIPSOMAX: Maximum possible cipso rule length.
*/
#define SMK_DIGITLEN 4
#define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
#define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
/*
* Values for parsing MAC rules
* SMK_ACCESS: Maximum possible combination of access permissions
* SMK_ACCESSLEN: Maximum length for a rule access field
* SMK_LOADLEN: Smack rule length
*/
#define SMK_OACCESS "rwxa"
#define SMK_ACCESS "rwxatl"
#define SMK_OACCESSLEN (sizeof(SMK_OACCESS) - 1)
#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
#define SMK_OLOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_OACCESSLEN)
#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
/*
* Stricly for CIPSO level manipulation.
* Set the category bit number in a smack label sized buffer.
*/
static inline void smack_catset_bit(unsigned int cat, char *catsetp)
{
if (cat == 0 || cat > (SMK_CIPSOLEN * 8))
return;
catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8);
}
/**
* smk_netlabel_audit_set - fill a netlbl_audit struct
* @nap: structure to fill
*/
static void smk_netlabel_audit_set(struct netlbl_audit *nap)
{
struct smack_known *skp = smk_of_current();
nap->loginuid = audit_get_loginuid(current);
nap->sessionid = audit_get_sessionid(current);
nap->secid = skp->smk_secid;
}
/*
* Value for parsing single label host rules
* "1.2.3.4 X"
*/
#define SMK_NETLBLADDRMIN 9
/**
* smk_set_access - add a rule to the rule list or replace an old rule
* @srp: the rule to add or replace
* @rule_list: the list of rules
* @rule_lock: the rule list lock
*
* Looks through the current subject/object/access list for
* the subject/object pair and replaces the access that was
* there. If the pair isn't found add it with the specified
* access.
*
* Returns 0 if nothing goes wrong or -ENOMEM if it fails
* during the allocation of the new pair to add.
*/
static int smk_set_access(struct smack_parsed_rule *srp,
struct list_head *rule_list,
struct mutex *rule_lock)
{
struct smack_rule *sp;
int found = 0;
int rc = 0;
mutex_lock(rule_lock);
/*
* Because the object label is less likely to match
* than the subject label check it first
*/
list_for_each_entry_rcu(sp, rule_list, list) {
if (sp->smk_object == srp->smk_object &&
sp->smk_subject == srp->smk_subject) {
found = 1;
sp->smk_access |= srp->smk_access1;
sp->smk_access &= ~srp->smk_access2;
break;
}
}
if (found == 0) {
sp = kmem_cache_zalloc(smack_rule_cache, GFP_KERNEL);
if (sp == NULL) {
rc = -ENOMEM;
goto out;
}
sp->smk_subject = srp->smk_subject;
sp->smk_object = srp->smk_object;
sp->smk_access = srp->smk_access1 & ~srp->smk_access2;
list_add_rcu(&sp->list, rule_list);
}
out:
mutex_unlock(rule_lock);
return rc;
}
/**
* smk_perm_from_str - parse smack accesses from a text string
* @string: a text string that contains a Smack accesses code
*
* Returns an integer with respective bits set for specified accesses.
*/
static int smk_perm_from_str(const char *string)
{
int perm = 0;
const char *cp;
for (cp = string; ; cp++)
switch (*cp) {
case '-':
break;
case 'r':
case 'R':
perm |= MAY_READ;
break;
case 'w':
case 'W':
perm |= MAY_WRITE;
break;
case 'x':
case 'X':
perm |= MAY_EXEC;
break;
case 'a':
case 'A':
perm |= MAY_APPEND;
break;
case 't':
case 'T':
perm |= MAY_TRANSMUTE;
break;
case 'l':
case 'L':
perm |= MAY_LOCK;
break;
case 'b':
case 'B':
perm |= MAY_BRINGUP;
break;
default:
return perm;
}
}
/**
* smk_fill_rule - Fill Smack rule from strings
* @subject: subject label string
* @object: object label string
* @access1: access string
* @access2: string with permissions to be removed
* @rule: Smack rule
* @import: if non-zero, import labels
* @len: label length limit
*
* Returns 0 on success, appropriate error code on failure.
*/
static int smk_fill_rule(const char *subject, const char *object,
const char *access1, const char *access2,
struct smack_parsed_rule *rule, int import,
int len)
{
const char *cp;
struct smack_known *skp;
if (import) {
rule->smk_subject = smk_import_entry(subject, len);
if (IS_ERR(rule->smk_subject))
return PTR_ERR(rule->smk_subject);
rule->smk_object = smk_import_entry(object, len);
if (IS_ERR(rule->smk_object))
return PTR_ERR(rule->smk_object);
} else {
cp = smk_parse_smack(subject, len);
if (IS_ERR(cp))
return PTR_ERR(cp);
skp = smk_find_entry(cp);
kfree(cp);
if (skp == NULL)
return -ENOENT;
rule->smk_subject = skp;
cp = smk_parse_smack(object, len);
if (IS_ERR(cp))
return PTR_ERR(cp);
skp = smk_find_entry(cp);
kfree(cp);
if (skp == NULL)
return -ENOENT;
rule->smk_object = skp;
}
rule->smk_access1 = smk_perm_from_str(access1);
if (access2)
rule->smk_access2 = smk_perm_from_str(access2);
else
rule->smk_access2 = ~rule->smk_access1;
return 0;
}
/**
* smk_parse_rule - parse Smack rule from load string
* @data: string to be parsed whose size is SMK_LOADLEN
* @rule: Smack rule
* @import: if non-zero, import labels
*
* Returns 0 on success, -1 on errors.
*/
static int smk_parse_rule(const char *data, struct smack_parsed_rule *rule,
int import)
{
int rc;
rc = smk_fill_rule(data, data + SMK_LABELLEN,
data + SMK_LABELLEN + SMK_LABELLEN, NULL, rule,
import, SMK_LABELLEN);
return rc;
}
/**
* smk_parse_long_rule - parse Smack rule from rule string
* @data: string to be parsed, null terminated
* @rule: Will be filled with Smack parsed rule
* @import: if non-zero, import labels
* @tokens: numer of substrings expected in data
*
* Returns number of processed bytes on success, -ERRNO on failure.
*/
static ssize_t smk_parse_long_rule(char *data, struct smack_parsed_rule *rule,
int import, int tokens)
{
ssize_t cnt = 0;
char *tok[4];
int rc;
int i;
/*
* Parsing the rule in-place, filling all white-spaces with '\0'
*/
for (i = 0; i < tokens; ++i) {
while (isspace(data[cnt]))
data[cnt++] = '\0';
if (data[cnt] == '\0')
/* Unexpected end of data */
return -EINVAL;
tok[i] = data + cnt;
while (data[cnt] && !isspace(data[cnt]))
++cnt;
}
while (isspace(data[cnt]))
data[cnt++] = '\0';
while (i < 4)
tok[i++] = NULL;
rc = smk_fill_rule(tok[0], tok[1], tok[2], tok[3], rule, import, 0);
return rc == 0 ? cnt : rc;
}
#define SMK_FIXED24_FMT 0 /* Fixed 24byte label format */
#define SMK_LONG_FMT 1 /* Variable long label format */
#define SMK_CHANGE_FMT 2 /* Rule modification format */
/**
* smk_write_rules_list - write() for any /smack rule file
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
* @rule_list: the list of rules to write to
* @rule_lock: lock for the rule list
* @format: /smack/load or /smack/load2 or /smack/change-rule format.
*
* Get one smack access rule from above.
* The format for SMK_LONG_FMT is:
* "subject<whitespace>object<whitespace>access[<whitespace>...]"
* The format for SMK_FIXED24_FMT is exactly:
* "subject object rwxat"
* The format for SMK_CHANGE_FMT is:
* "subject<whitespace>object<whitespace>
* acc_enable<whitespace>acc_disable[<whitespace>...]"
*/
static ssize_t smk_write_rules_list(struct file *file, const char __user *buf,
size_t count, loff_t *ppos,
struct list_head *rule_list,
struct mutex *rule_lock, int format)
{
struct smack_parsed_rule rule;
char *data;
int rc;
int trunc = 0;
int tokens;
ssize_t cnt = 0;
/*
* No partial writes.
* Enough data must be present.
*/
if (*ppos != 0)
return -EINVAL;
if (format == SMK_FIXED24_FMT) {
/*
* Minor hack for backward compatibility
*/
if (count < SMK_OLOADLEN || count > SMK_LOADLEN)
return -EINVAL;
} else {
if (count >= PAGE_SIZE) {
count = PAGE_SIZE - 1;
trunc = 1;
}
}
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
/*
* In case of parsing only part of user buf,
* avoid having partial rule at the data buffer
*/
if (trunc) {
while (count > 0 && (data[count - 1] != '\n'))
--count;
if (count == 0) {
rc = -EINVAL;
goto out;
}
}
data[count] = '\0';
tokens = (format == SMK_CHANGE_FMT ? 4 : 3);
while (cnt < count) {
if (format == SMK_FIXED24_FMT) {
rc = smk_parse_rule(data, &rule, 1);
if (rc < 0)
goto out;
cnt = count;
} else {
rc = smk_parse_long_rule(data + cnt, &rule, 1, tokens);
if (rc < 0)
goto out;
if (rc == 0) {
rc = -EINVAL;
goto out;
}
cnt += rc;
}
if (rule_list == NULL)
rc = smk_set_access(&rule, &rule.smk_subject->smk_rules,
&rule.smk_subject->smk_rules_lock);
else
rc = smk_set_access(&rule, rule_list, rule_lock);
if (rc)
goto out;
}
rc = cnt;
out:
kfree(data);
return rc;
}
/*
* Core logic for smackfs seq list operations.
*/
static void *smk_seq_start(struct seq_file *s, loff_t *pos,
struct list_head *head)
{
struct list_head *list;
int i = *pos;
rcu_read_lock();
for (list = rcu_dereference(list_next_rcu(head));
list != head;
list = rcu_dereference(list_next_rcu(list))) {
if (i-- == 0)
return list;
}
return NULL;
}
static void *smk_seq_next(struct seq_file *s, void *v, loff_t *pos,
struct list_head *head)
{
struct list_head *list = v;
++*pos;
list = rcu_dereference(list_next_rcu(list));
return (list == head) ? NULL : list;
}
static void smk_seq_stop(struct seq_file *s, void *v)
{
rcu_read_unlock();
}
static void smk_rule_show(struct seq_file *s, struct smack_rule *srp, int max)
{
/*
* Don't show any rules with label names too long for
* interface file (/smack/load or /smack/load2)
* because you should expect to be able to write
* anything you read back.
*/
if (strlen(srp->smk_subject->smk_known) >= max ||
strlen(srp->smk_object->smk_known) >= max)
return;
if (srp->smk_access == 0)
return;
seq_printf(s, "%s %s",
srp->smk_subject->smk_known,
srp->smk_object->smk_known);
seq_putc(s, ' ');
if (srp->smk_access & MAY_READ)
seq_putc(s, 'r');
if (srp->smk_access & MAY_WRITE)
seq_putc(s, 'w');
if (srp->smk_access & MAY_EXEC)
seq_putc(s, 'x');
if (srp->smk_access & MAY_APPEND)
seq_putc(s, 'a');
if (srp->smk_access & MAY_TRANSMUTE)
seq_putc(s, 't');
if (srp->smk_access & MAY_LOCK)
seq_putc(s, 'l');
if (srp->smk_access & MAY_BRINGUP)
seq_putc(s, 'b');
seq_putc(s, '\n');
}
/*
* Seq_file read operations for /smack/load
*/
static void *load2_seq_start(struct seq_file *s, loff_t *pos)
{
return smk_seq_start(s, pos, &smack_known_list);
}
static void *load2_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
return smk_seq_next(s, v, pos, &smack_known_list);
}
static int load_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp;
struct smack_known *skp =
list_entry_rcu(list, struct smack_known, list);
list_for_each_entry_rcu(srp, &skp->smk_rules, list)
smk_rule_show(s, srp, SMK_LABELLEN);
return 0;
}
static const struct seq_operations load_seq_ops = {
.start = load2_seq_start,
.next = load2_seq_next,
.show = load_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_load - open() for /smack/load
* @inode: inode structure representing file
* @file: "load" file pointer
*
* For reading, use load_seq_* seq_file reading operations.
*/
static int smk_open_load(struct inode *inode, struct file *file)
{
return seq_open(file, &load_seq_ops);
}
/**
* smk_write_load - write() for /smack/load
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
*/
static ssize_t smk_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
SMK_FIXED24_FMT);
}
static const struct file_operations smk_load_ops = {
.open = smk_open_load,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load,
.release = seq_release,
};
/**
* smk_cipso_doi - initialize the CIPSO domain
*/
static void smk_cipso_doi(void)
{
int rc;
struct cipso_v4_doi *doip;
struct netlbl_audit nai;
smk_netlabel_audit_set(&nai);
rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d remove rc = %d\n",
__func__, __LINE__, rc);
doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL);
if (doip == NULL)
panic("smack: Failed to initialize cipso DOI.\n");
doip->map.std = NULL;
doip->doi = smk_cipso_doi_value;
doip->type = CIPSO_V4_MAP_PASS;
doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
doip->tags[rc] = CIPSO_V4_TAG_INVALID;
rc = netlbl_cfg_cipsov4_add(doip, &nai);
if (rc != 0) {
printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
__func__, __LINE__, rc);
kfree(doip);
return;
}
rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
if (rc != 0) {
printk(KERN_WARNING "%s:%d map add rc = %d\n",
__func__, __LINE__, rc);
kfree(doip);
return;
}
}
/**
* smk_unlbl_ambient - initialize the unlabeled domain
* @oldambient: previous domain string
*/
static void smk_unlbl_ambient(char *oldambient)
{
int rc;
struct netlbl_audit nai;
smk_netlabel_audit_set(&nai);
if (oldambient != NULL) {
rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d remove rc = %d\n",
__func__, __LINE__, rc);
}
if (smack_net_ambient == NULL)
smack_net_ambient = &smack_known_floor;
rc = netlbl_cfg_unlbl_map_add(smack_net_ambient->smk_known, PF_INET,
NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d add rc = %d\n",
__func__, __LINE__, rc);
}
/*
* Seq_file read operations for /smack/cipso
*/
static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
{
return smk_seq_start(s, pos, &smack_known_list);
}
static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
return smk_seq_next(s, v, pos, &smack_known_list);
}
/*
* Print cipso labels in format:
* label level[/cat[,cat]]
*/
static int cipso_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_known *skp =
list_entry_rcu(list, struct smack_known, list);
struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
char sep = '/';
int i;
/*
* Don't show a label that could not have been set using
* /smack/cipso. This is in support of the notion that
* anything read from /smack/cipso ought to be writeable
* to /smack/cipso.
*
* /smack/cipso2 should be used instead.
*/
if (strlen(skp->smk_known) >= SMK_LABELLEN)
return 0;
seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
i = netlbl_catmap_walk(cmp, i + 1)) {
seq_printf(s, "%c%d", sep, i);
sep = ',';
}
seq_putc(s, '\n');
return 0;
}
static const struct seq_operations cipso_seq_ops = {
.start = cipso_seq_start,
.next = cipso_seq_next,
.show = cipso_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_cipso - open() for /smack/cipso
* @inode: inode structure representing file
* @file: "cipso" file pointer
*
* Connect our cipso_seq_* operations with /smack/cipso
* file_operations
*/
static int smk_open_cipso(struct inode *inode, struct file *file)
{
return seq_open(file, &cipso_seq_ops);
}
/**
* smk_set_cipso - do the work for write() for cipso and cipso2
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
* @format: /smack/cipso or /smack/cipso2
*
* Accepts only one cipso rule per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_set_cipso(struct file *file, const char __user *buf,
size_t count, loff_t *ppos, int format)
{
struct smack_known *skp;
struct netlbl_lsm_secattr ncats;
char mapcatset[SMK_CIPSOLEN];
int maplevel;
unsigned int cat;
int catlen;
ssize_t rc = -EINVAL;
char *data = NULL;
char *rule;
int ret;
int i;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (format == SMK_FIXED24_FMT &&
(count < SMK_CIPSOMIN || count > SMK_CIPSOMAX))
return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
rule = data;
/*
* Only allow one writer at a time. Writes should be
* quite rare and small in any case.
*/
mutex_lock(&smack_cipso_lock);
skp = smk_import_entry(rule, 0);
if (IS_ERR(skp)) {
rc = PTR_ERR(skp);
goto out;
}
if (format == SMK_FIXED24_FMT)
rule += SMK_LABELLEN;
else
rule += strlen(skp->smk_known) + 1;
ret = sscanf(rule, "%d", &maplevel);
if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
goto out;
rule += SMK_DIGITLEN;
ret = sscanf(rule, "%d", &catlen);
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
goto out;
if (format == SMK_FIXED24_FMT &&
count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
goto out;
memset(mapcatset, 0, sizeof(mapcatset));
for (i = 0; i < catlen; i++) {
rule += SMK_DIGITLEN;
ret = sscanf(rule, "%u", &cat);
if (ret != 1 || cat > SMACK_CIPSO_MAXCATNUM)
goto out;
smack_catset_bit(cat, mapcatset);
}
rc = smk_netlbl_mls(maplevel, mapcatset, &ncats, SMK_CIPSOLEN);
if (rc >= 0) {
netlbl_catmap_free(skp->smk_netlabel.attr.mls.cat);
skp->smk_netlabel.attr.mls.cat = ncats.attr.mls.cat;
skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
rc = count;
}
out:
mutex_unlock(&smack_cipso_lock);
kfree(data);
return rc;
}
/**
* smk_write_cipso - write() for /smack/cipso
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one cipso rule per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return smk_set_cipso(file, buf, count, ppos, SMK_FIXED24_FMT);
}
static const struct file_operations smk_cipso_ops = {
.open = smk_open_cipso,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_cipso,
.release = seq_release,
};
/*
* Seq_file read operations for /smack/cipso2
*/
/*
* Print cipso labels in format:
* label level[/cat[,cat]]
*/
static int cipso2_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_known *skp =
list_entry_rcu(list, struct smack_known, list);
struct netlbl_lsm_catmap *cmp = skp->smk_netlabel.attr.mls.cat;
char sep = '/';
int i;
seq_printf(s, "%s %3d", skp->smk_known, skp->smk_netlabel.attr.mls.lvl);
for (i = netlbl_catmap_walk(cmp, 0); i >= 0;
i = netlbl_catmap_walk(cmp, i + 1)) {
seq_printf(s, "%c%d", sep, i);
sep = ',';
}
seq_putc(s, '\n');
return 0;
}
static const struct seq_operations cipso2_seq_ops = {
.start = cipso_seq_start,
.next = cipso_seq_next,
.show = cipso2_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_cipso2 - open() for /smack/cipso2
* @inode: inode structure representing file
* @file: "cipso2" file pointer
*
* Connect our cipso_seq_* operations with /smack/cipso2
* file_operations
*/
static int smk_open_cipso2(struct inode *inode, struct file *file)
{
return seq_open(file, &cipso2_seq_ops);
}
/**
* smk_write_cipso2 - write() for /smack/cipso2
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one cipso rule per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_cipso2(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return smk_set_cipso(file, buf, count, ppos, SMK_LONG_FMT);
}
static const struct file_operations smk_cipso2_ops = {
.open = smk_open_cipso2,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_cipso2,
.release = seq_release,
};
/*
* Seq_file read operations for /smack/netlabel
*/
static void *net4addr_seq_start(struct seq_file *s, loff_t *pos)
{
return smk_seq_start(s, pos, &smk_net4addr_list);
}
static void *net4addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
return smk_seq_next(s, v, pos, &smk_net4addr_list);
}
/*
* Print host/label pairs
*/
static int net4addr_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smk_net4addr *skp =
list_entry_rcu(list, struct smk_net4addr, list);
char *kp = SMACK_CIPSO_OPTION;
if (skp->smk_label != NULL)
kp = skp->smk_label->smk_known;
seq_printf(s, "%pI4/%d %s\n", &skp->smk_host.s_addr,
skp->smk_masks, kp);
return 0;
}
static const struct seq_operations net4addr_seq_ops = {
.start = net4addr_seq_start,
.next = net4addr_seq_next,
.show = net4addr_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_net4addr - open() for /smack/netlabel
* @inode: inode structure representing file
* @file: "netlabel" file pointer
*
* Connect our net4addr_seq_* operations with /smack/netlabel
* file_operations
*/
static int smk_open_net4addr(struct inode *inode, struct file *file)
{
return seq_open(file, &net4addr_seq_ops);
}
/**
* smk_net4addr_insert
* @new : netlabel to insert
*
* This helper insert netlabel in the smack_net4addrs list
* sorted by netmask length (longest to smallest)
* locked by &smk_net4addr_lock in smk_write_net4addr
*
*/
static void smk_net4addr_insert(struct smk_net4addr *new)
{
struct smk_net4addr *m;
struct smk_net4addr *m_next;
if (list_empty(&smk_net4addr_list)) {
list_add_rcu(&new->list, &smk_net4addr_list);
return;
}
m = list_entry_rcu(smk_net4addr_list.next,
struct smk_net4addr, list);
/* the comparison '>' is a bit hacky, but works */
if (new->smk_masks > m->smk_masks) {
list_add_rcu(&new->list, &smk_net4addr_list);
return;
}
list_for_each_entry_rcu(m, &smk_net4addr_list, list) {
if (list_is_last(&m->list, &smk_net4addr_list)) {
list_add_rcu(&new->list, &m->list);
return;
}
m_next = list_entry_rcu(m->list.next,
struct smk_net4addr, list);
if (new->smk_masks > m_next->smk_masks) {
list_add_rcu(&new->list, &m->list);
return;
}
}
}
/**
* smk_write_net4addr - write() for /smack/netlabel
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one net4addr per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smk_net4addr *snp;
struct sockaddr_in newname;
char *smack;
struct smack_known *skp = NULL;
char *data;
char *host = (char *)&newname.sin_addr.s_addr;
int rc;
struct netlbl_audit audit_info;
struct in_addr mask;
unsigned int m;
unsigned int masks;
int found;
u32 mask_bits = (1<<31);
__be32 nsa;
u32 temp_mask;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
* "<addr/mask, as a.b.c.d/e><space><label>"
* "<addr, as a.b.c.d><space><label>"
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_NETLBLADDRMIN)
return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
smack = kzalloc(count + 1, GFP_KERNEL);
if (smack == NULL) {
rc = -ENOMEM;
goto free_data_out;
}
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%u %s",
&host[0], &host[1], &host[2], &host[3], &masks, smack);
if (rc != 6) {
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
&host[0], &host[1], &host[2], &host[3], smack);
if (rc != 5) {
rc = -EINVAL;
goto free_out;
}
m = BEBITS;
masks = 32;
}
if (masks > BEBITS) {
rc = -EINVAL;
goto free_out;
}
/*
* If smack begins with '-', it is an option, don't import it
*/
if (smack[0] != '-') {
skp = smk_import_entry(smack, 0);
if (IS_ERR(skp)) {
rc = PTR_ERR(skp);
goto free_out;
}
} else {
/*
* Only the -CIPSO option is supported for IPv4
*/
if (strcmp(smack, SMACK_CIPSO_OPTION) != 0) {
rc = -EINVAL;
goto free_out;
}
}
for (m = masks, temp_mask = 0; m > 0; m--) {
temp_mask |= mask_bits;
mask_bits >>= 1;
}
mask.s_addr = cpu_to_be32(temp_mask);
newname.sin_addr.s_addr &= mask.s_addr;
/*
* Only allow one writer at a time. Writes should be
* quite rare and small in any case.
*/
mutex_lock(&smk_net4addr_lock);
nsa = newname.sin_addr.s_addr;
/* try to find if the prefix is already in the list */
found = 0;
list_for_each_entry_rcu(snp, &smk_net4addr_list, list) {
if (snp->smk_host.s_addr == nsa && snp->smk_masks == masks) {
found = 1;
break;
}
}
smk_netlabel_audit_set(&audit_info);
if (found == 0) {
snp = kzalloc(sizeof(*snp), GFP_KERNEL);
if (snp == NULL)
rc = -ENOMEM;
else {
rc = 0;
snp->smk_host.s_addr = newname.sin_addr.s_addr;
snp->smk_mask.s_addr = mask.s_addr;
snp->smk_label = skp;
snp->smk_masks = masks;
smk_net4addr_insert(snp);
}
} else {
/*
* Delete the unlabeled entry, only if the previous label
* wasn't the special CIPSO option
*/
if (snp->smk_label != NULL)
rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
&snp->smk_host, &snp->smk_mask,
PF_INET, &audit_info);
else
rc = 0;
snp->smk_label = skp;
}
/*
* Now tell netlabel about the single label nature of
* this host so that incoming packets get labeled.
* but only if we didn't get the special CIPSO option
*/
if (rc == 0 && skp != NULL)
rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
&snp->smk_host, &snp->smk_mask, PF_INET,
snp->smk_label->smk_secid, &audit_info);
if (rc == 0)
rc = count;
mutex_unlock(&smk_net4addr_lock);
free_out:
kfree(smack);
free_data_out:
kfree(data);
return rc;
}
static const struct file_operations smk_net4addr_ops = {
.open = smk_open_net4addr,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_net4addr,
.release = seq_release,
};
#if IS_ENABLED(CONFIG_IPV6)
/*
* Seq_file read operations for /smack/netlabel6
*/
static void *net6addr_seq_start(struct seq_file *s, loff_t *pos)
{
return smk_seq_start(s, pos, &smk_net6addr_list);
}
static void *net6addr_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
return smk_seq_next(s, v, pos, &smk_net6addr_list);
}
/*
* Print host/label pairs
*/
static int net6addr_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smk_net6addr *skp =
list_entry(list, struct smk_net6addr, list);
if (skp->smk_label != NULL)
seq_printf(s, "%pI6/%d %s\n", &skp->smk_host, skp->smk_masks,
skp->smk_label->smk_known);
return 0;
}
static const struct seq_operations net6addr_seq_ops = {
.start = net6addr_seq_start,
.next = net6addr_seq_next,
.show = net6addr_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_net6addr - open() for /smack/netlabel
* @inode: inode structure representing file
* @file: "netlabel" file pointer
*
* Connect our net6addr_seq_* operations with /smack/netlabel
* file_operations
*/
static int smk_open_net6addr(struct inode *inode, struct file *file)
{
return seq_open(file, &net6addr_seq_ops);
}
/**
* smk_net6addr_insert
* @new : entry to insert
*
* This inserts an entry in the smack_net6addrs list
* sorted by netmask length (longest to smallest)
* locked by &smk_net6addr_lock in smk_write_net6addr
*
*/
static void smk_net6addr_insert(struct smk_net6addr *new)
{
struct smk_net6addr *m_next;
struct smk_net6addr *m;
if (list_empty(&smk_net6addr_list)) {
list_add_rcu(&new->list, &smk_net6addr_list);
return;
}
m = list_entry_rcu(smk_net6addr_list.next,
struct smk_net6addr, list);
if (new->smk_masks > m->smk_masks) {
list_add_rcu(&new->list, &smk_net6addr_list);
return;
}
list_for_each_entry_rcu(m, &smk_net6addr_list, list) {
if (list_is_last(&m->list, &smk_net6addr_list)) {
list_add_rcu(&new->list, &m->list);
return;
}
m_next = list_entry_rcu(m->list.next,
struct smk_net6addr, list);
if (new->smk_masks > m_next->smk_masks) {
list_add_rcu(&new->list, &m->list);
return;
}
}
}
/**
* smk_write_net6addr - write() for /smack/netlabel
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one net6addr per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_net6addr(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smk_net6addr *snp;
struct in6_addr newname;
struct in6_addr fullmask;
struct smack_known *skp = NULL;
char *smack;
char *data;
int rc = 0;
int found = 0;
int i;
unsigned int scanned[8];
unsigned int m;
unsigned int mask = 128;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
* "<addr/mask, as a:b:c:d:e:f:g:h/e><space><label>"
* "<addr, as a:b:c:d:e:f:g:h><space><label>"
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_NETLBLADDRMIN)
return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
smack = kzalloc(count + 1, GFP_KERNEL);
if (smack == NULL) {
rc = -ENOMEM;
goto free_data_out;
}
i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x/%u %s",
&scanned[0], &scanned[1], &scanned[2], &scanned[3],
&scanned[4], &scanned[5], &scanned[6], &scanned[7],
&mask, smack);
if (i != 10) {
i = sscanf(data, "%x:%x:%x:%x:%x:%x:%x:%x %s",
&scanned[0], &scanned[1], &scanned[2],
&scanned[3], &scanned[4], &scanned[5],
&scanned[6], &scanned[7], smack);
if (i != 9) {
rc = -EINVAL;
goto free_out;
}
}
if (mask > 128) {
rc = -EINVAL;
goto free_out;
}
for (i = 0; i < 8; i++) {
if (scanned[i] > 0xffff) {
rc = -EINVAL;
goto free_out;
}
newname.s6_addr16[i] = htons(scanned[i]);
}
/*
* If smack begins with '-', it is an option, don't import it
*/
if (smack[0] != '-') {
skp = smk_import_entry(smack, 0);
if (IS_ERR(skp)) {
rc = PTR_ERR(skp);
goto free_out;
}
} else {
/*
* Only -DELETE is supported for IPv6
*/
if (strcmp(smack, SMACK_DELETE_OPTION) != 0) {
rc = -EINVAL;
goto free_out;
}
}
for (i = 0, m = mask; i < 8; i++) {
if (m >= 16) {
fullmask.s6_addr16[i] = 0xffff;
m -= 16;
} else if (m > 0) {
fullmask.s6_addr16[i] = (1 << m) - 1;
m = 0;
} else
fullmask.s6_addr16[i] = 0;
newname.s6_addr16[i] &= fullmask.s6_addr16[i];
}
/*
* Only allow one writer at a time. Writes should be
* quite rare and small in any case.
*/
mutex_lock(&smk_net6addr_lock);
/*
* Try to find the prefix in the list
*/
list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
if (mask != snp->smk_masks)
continue;
for (found = 1, i = 0; i < 8; i++) {
if (newname.s6_addr16[i] !=
snp->smk_host.s6_addr16[i]) {
found = 0;
break;
}
}
if (found == 1)
break;
}
if (found == 0) {
snp = kzalloc(sizeof(*snp), GFP_KERNEL);
if (snp == NULL)
rc = -ENOMEM;
else {
snp->smk_host = newname;
snp->smk_mask = fullmask;
snp->smk_masks = mask;
snp->smk_label = skp;
smk_net6addr_insert(snp);
}
} else {
snp->smk_label = skp;
}
if (rc == 0)
rc = count;
mutex_unlock(&smk_net6addr_lock);
free_out:
kfree(smack);
free_data_out:
kfree(data);
return rc;
}
static const struct file_operations smk_net6addr_ops = {
.open = smk_open_net6addr,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_net6addr,
.release = seq_release,
};
#endif /* CONFIG_IPV6 */
/**
* smk_read_doi - read() for /smack/doi
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_doi(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d", smk_cipso_doi_value);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_doi - write() for /smack/doi
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_doi(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
int i;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
smk_cipso_doi_value = i;
smk_cipso_doi();
return count;
}
static const struct file_operations smk_doi_ops = {
.read = smk_read_doi,
.write = smk_write_doi,
.llseek = default_llseek,
};
/**
* smk_read_direct - read() for /smack/direct
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_direct(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d", smack_cipso_direct);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_direct - write() for /smack/direct
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_direct(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_known *skp;
char temp[80];
int i;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
/*
* Don't do anything if the value hasn't actually changed.
* If it is changing reset the level on entries that were
* set up to be direct when they were created.
*/
if (smack_cipso_direct != i) {
mutex_lock(&smack_known_lock);
list_for_each_entry_rcu(skp, &smack_known_list, list)
if (skp->smk_netlabel.attr.mls.lvl ==
smack_cipso_direct)
skp->smk_netlabel.attr.mls.lvl = i;
smack_cipso_direct = i;
mutex_unlock(&smack_known_lock);
}
return count;
}
static const struct file_operations smk_direct_ops = {
.read = smk_read_direct,
.write = smk_write_direct,
.llseek = default_llseek,
};
/**
* smk_read_mapped - read() for /smack/mapped
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_mapped(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d", smack_cipso_mapped);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_mapped - write() for /smack/mapped
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_mapped(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_known *skp;
char temp[80];
int i;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
/*
* Don't do anything if the value hasn't actually changed.
* If it is changing reset the level on entries that were
* set up to be mapped when they were created.
*/
if (smack_cipso_mapped != i) {
mutex_lock(&smack_known_lock);
list_for_each_entry_rcu(skp, &smack_known_list, list)
if (skp->smk_netlabel.attr.mls.lvl ==
smack_cipso_mapped)
skp->smk_netlabel.attr.mls.lvl = i;
smack_cipso_mapped = i;
mutex_unlock(&smack_known_lock);
}
return count;
}
static const struct file_operations smk_mapped_ops = {
.read = smk_read_mapped,
.write = smk_write_mapped,
.llseek = default_llseek,
};
/**
* smk_read_ambient - read() for /smack/ambient
* @filp: file pointer, not actually used
* @buf: where to put the result
* @cn: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_ambient(struct file *filp, char __user *buf,
size_t cn, loff_t *ppos)
{
ssize_t rc;
int asize;
if (*ppos != 0)
return 0;
/*
* Being careful to avoid a problem in the case where
* smack_net_ambient gets changed in midstream.
*/
mutex_lock(&smack_ambient_lock);
asize = strlen(smack_net_ambient->smk_known) + 1;
if (cn >= asize)
rc = simple_read_from_buffer(buf, cn, ppos,
smack_net_ambient->smk_known,
asize);
else
rc = -EINVAL;
mutex_unlock(&smack_ambient_lock);
return rc;
}
/**
* smk_write_ambient - write() for /smack/ambient
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_ambient(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_known *skp;
char *oldambient;
char *data;
int rc = count;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
skp = smk_import_entry(data, count);
if (IS_ERR(skp)) {
rc = PTR_ERR(skp);
goto out;
}
mutex_lock(&smack_ambient_lock);
oldambient = smack_net_ambient->smk_known;
smack_net_ambient = skp;
smk_unlbl_ambient(oldambient);
mutex_unlock(&smack_ambient_lock);
out:
kfree(data);
return rc;
}
static const struct file_operations smk_ambient_ops = {
.read = smk_read_ambient,
.write = smk_write_ambient,
.llseek = default_llseek,
};
/*
* Seq_file operations for /smack/onlycap
*/
static void *onlycap_seq_start(struct seq_file *s, loff_t *pos)
{
return smk_seq_start(s, pos, &smack_onlycap_list);
}
static void *onlycap_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
return smk_seq_next(s, v, pos, &smack_onlycap_list);
}
static int onlycap_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_known_list_elem *sklep =
list_entry_rcu(list, struct smack_known_list_elem, list);
seq_puts(s, sklep->smk_label->smk_known);
seq_putc(s, ' ');
return 0;
}
static const struct seq_operations onlycap_seq_ops = {
.start = onlycap_seq_start,
.next = onlycap_seq_next,
.show = onlycap_seq_show,
.stop = smk_seq_stop,
};
static int smk_open_onlycap(struct inode *inode, struct file *file)
{
return seq_open(file, &onlycap_seq_ops);
}
/**
* smk_list_swap_rcu - swap public list with a private one in RCU-safe way
* The caller must hold appropriate mutex to prevent concurrent modifications
* to the public list.
* Private list is assumed to be not accessible to other threads yet.
*
* @public: public list
* @private: private list
*/
static void smk_list_swap_rcu(struct list_head *public,
struct list_head *private)
{
struct list_head *first, *last;
if (list_empty(public)) {
list_splice_init_rcu(private, public, synchronize_rcu);
} else {
/* Remember public list before replacing it */
first = public->next;
last = public->prev;
/* Publish private list in place of public in RCU-safe way */
private->prev->next = public;
private->next->prev = public;
rcu_assign_pointer(public->next, private->next);
public->prev = private->prev;
synchronize_rcu();
/* When all readers are done with the old public list,
* attach it in place of private */
private->next = first;
private->prev = last;
first->prev = private;
last->next = private;
}
}
/**
* smk_parse_label_list - parse list of Smack labels, separated by spaces
*
* @data: the string to parse
* @private: destination list
*
* Returns zero on success or error code, as appropriate
*/
static int smk_parse_label_list(char *data, struct list_head *list)
{
char *tok;
struct smack_known *skp;
struct smack_known_list_elem *sklep;
while ((tok = strsep(&data, " ")) != NULL) {
if (!*tok)
continue;
skp = smk_import_entry(tok, 0);
if (IS_ERR(skp))
return PTR_ERR(skp);
sklep = kzalloc(sizeof(*sklep), GFP_KERNEL);
if (sklep == NULL)
return -ENOMEM;
sklep->smk_label = skp;
list_add(&sklep->list, list);
}
return 0;
}
/**
* smk_destroy_label_list - destroy a list of smack_known_list_elem
* @head: header pointer of the list to destroy
*/
void smk_destroy_label_list(struct list_head *list)
{
struct smack_known_list_elem *sklep;
struct smack_known_list_elem *sklep2;
list_for_each_entry_safe(sklep, sklep2, list, list)
kfree(sklep);
INIT_LIST_HEAD(list);
}
/**
* smk_write_onlycap - write() for smackfs/onlycap
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *data;
LIST_HEAD(list_tmp);
int rc;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
rc = smk_parse_label_list(data, &list_tmp);
kfree(data);
/*
* Clear the smack_onlycap on invalid label errors. This means
* that we can pass a null string to unset the onlycap value.
*
* Importing will also reject a label beginning with '-',
* so "-usecapabilities" will also work.
*
* But do so only on invalid label, not on system errors.
* The invalid label must be first to count as clearing attempt.
*/
if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
mutex_lock(&smack_onlycap_lock);
smk_list_swap_rcu(&smack_onlycap_list, &list_tmp);
mutex_unlock(&smack_onlycap_lock);
rc = count;
}
smk_destroy_label_list(&list_tmp);
return rc;
}
static const struct file_operations smk_onlycap_ops = {
.open = smk_open_onlycap,
.read = seq_read,
.write = smk_write_onlycap,
.llseek = seq_lseek,
.release = seq_release,
};
#ifdef CONFIG_SECURITY_SMACK_BRINGUP
/**
* smk_read_unconfined - read() for smackfs/unconfined
* @filp: file pointer, not actually used
* @buf: where to put the result
* @cn: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_unconfined(struct file *filp, char __user *buf,
size_t cn, loff_t *ppos)
{
char *smack = "";
ssize_t rc = -EINVAL;
int asize;
if (*ppos != 0)
return 0;
if (smack_unconfined != NULL)
smack = smack_unconfined->smk_known;
asize = strlen(smack) + 1;
if (cn >= asize)
rc = simple_read_from_buffer(buf, cn, ppos, smack, asize);
return rc;
}
/**
* smk_write_unconfined - write() for smackfs/unconfined
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_unconfined(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *data;
struct smack_known *skp;
int rc = count;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
/*
* Clear the smack_unconfined on invalid label errors. This means
* that we can pass a null string to unset the unconfined value.
*
* Importing will also reject a label beginning with '-',
* so "-confine" will also work.
*
* But do so only on invalid label, not on system errors.
*/
skp = smk_import_entry(data, count);
if (PTR_ERR(skp) == -EINVAL)
skp = NULL;
else if (IS_ERR(skp)) {
rc = PTR_ERR(skp);
goto freeout;
}
smack_unconfined = skp;
freeout:
kfree(data);
return rc;
}
static const struct file_operations smk_unconfined_ops = {
.read = smk_read_unconfined,
.write = smk_write_unconfined,
.llseek = default_llseek,
};
#endif /* CONFIG_SECURITY_SMACK_BRINGUP */
/**
* smk_read_logging - read() for /smack/logging
* @filp: file pointer, not actually used
* @buf: where to put the result
* @cn: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_logging(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[32];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d\n", log_policy);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_logging - write() for /smack/logging
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_logging(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char temp[32];
int i;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
if (i < 0 || i > 3)
return -EINVAL;
log_policy = i;
return count;
}
static const struct file_operations smk_logging_ops = {
.read = smk_read_logging,
.write = smk_write_logging,
.llseek = default_llseek,
};
/*
* Seq_file read operations for /smack/load-self
*/
static void *load_self_seq_start(struct seq_file *s, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_start(s, pos, &tsp->smk_rules);
}
static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_next(s, v, pos, &tsp->smk_rules);
}
static int load_self_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp =
list_entry_rcu(list, struct smack_rule, list);
smk_rule_show(s, srp, SMK_LABELLEN);
return 0;
}
static const struct seq_operations load_self_seq_ops = {
.start = load_self_seq_start,
.next = load_self_seq_next,
.show = load_self_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_load_self - open() for /smack/load-self2
* @inode: inode structure representing file
* @file: "load" file pointer
*
* For reading, use load_seq_* seq_file reading operations.
*/
static int smk_open_load_self(struct inode *inode, struct file *file)
{
return seq_open(file, &load_self_seq_ops);
}
/**
* smk_write_load_self - write() for /smack/load-self
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
*/
static ssize_t smk_write_load_self(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
&tsp->smk_rules_lock, SMK_FIXED24_FMT);
}
static const struct file_operations smk_load_self_ops = {
.open = smk_open_load_self,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load_self,
.release = seq_release,
};
/**
* smk_user_access - handle access check transaction
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_user_access(struct file *file, const char __user *buf,
size_t count, loff_t *ppos, int format)
{
struct smack_parsed_rule rule;
char *data;
int res;
data = simple_transaction_get(file, buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
if (format == SMK_FIXED24_FMT) {
if (count < SMK_LOADLEN)
return -EINVAL;
res = smk_parse_rule(data, &rule, 0);
} else {
/*
* simple_transaction_get() returns null-terminated data
*/
res = smk_parse_long_rule(data, &rule, 0, 3);
}
if (res >= 0)
res = smk_access(rule.smk_subject, rule.smk_object,
rule.smk_access1, NULL);
else if (res != -ENOENT)
return res;
/*
* smk_access() can return a value > 0 in the "bringup" case.
*/
data[0] = res >= 0 ? '1' : '0';
data[1] = '\0';
simple_transaction_set(file, 2);
if (format == SMK_FIXED24_FMT)
return SMK_LOADLEN;
return count;
}
/**
* smk_write_access - handle access check transaction
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_write_access(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return smk_user_access(file, buf, count, ppos, SMK_FIXED24_FMT);
}
static const struct file_operations smk_access_ops = {
.write = smk_write_access,
.read = simple_transaction_read,
.release = simple_transaction_release,
.llseek = generic_file_llseek,
};
/*
* Seq_file read operations for /smack/load2
*/
static int load2_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp;
struct smack_known *skp =
list_entry_rcu(list, struct smack_known, list);
list_for_each_entry_rcu(srp, &skp->smk_rules, list)
smk_rule_show(s, srp, SMK_LONGLABEL);
return 0;
}
static const struct seq_operations load2_seq_ops = {
.start = load2_seq_start,
.next = load2_seq_next,
.show = load2_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_load2 - open() for /smack/load2
* @inode: inode structure representing file
* @file: "load2" file pointer
*
* For reading, use load2_seq_* seq_file reading operations.
*/
static int smk_open_load2(struct inode *inode, struct file *file)
{
return seq_open(file, &load2_seq_ops);
}
/**
* smk_write_load2 - write() for /smack/load2
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
*/
static ssize_t smk_write_load2(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/*
* Must have privilege.
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
SMK_LONG_FMT);
}
static const struct file_operations smk_load2_ops = {
.open = smk_open_load2,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load2,
.release = seq_release,
};
/*
* Seq_file read operations for /smack/load-self2
*/
static void *load_self2_seq_start(struct seq_file *s, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_start(s, pos, &tsp->smk_rules);
}
static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_next(s, v, pos, &tsp->smk_rules);
}
static int load_self2_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp =
list_entry_rcu(list, struct smack_rule, list);
smk_rule_show(s, srp, SMK_LONGLABEL);
return 0;
}
static const struct seq_operations load_self2_seq_ops = {
.start = load_self2_seq_start,
.next = load_self2_seq_next,
.show = load_self2_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_load_self2 - open() for /smack/load-self2
* @inode: inode structure representing file
* @file: "load" file pointer
*
* For reading, use load_seq_* seq_file reading operations.
*/
static int smk_open_load_self2(struct inode *inode, struct file *file)
{
return seq_open(file, &load_self2_seq_ops);
}
/**
* smk_write_load_self2 - write() for /smack/load-self2
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
*/
static ssize_t smk_write_load_self2(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules,
&tsp->smk_rules_lock, SMK_LONG_FMT);
}
static const struct file_operations smk_load_self2_ops = {
.open = smk_open_load_self2,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load_self2,
.release = seq_release,
};
/**
* smk_write_access2 - handle access check transaction
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_write_access2(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
return smk_user_access(file, buf, count, ppos, SMK_LONG_FMT);
}
static const struct file_operations smk_access2_ops = {
.write = smk_write_access2,
.read = simple_transaction_read,
.release = simple_transaction_release,
.llseek = generic_file_llseek,
};
/**
* smk_write_revoke_subj - write() for /smack/revoke-subject
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_write_revoke_subj(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *data;
const char *cp;
struct smack_known *skp;
struct smack_rule *sp;
struct list_head *rule_list;
struct mutex *rule_lock;
int rc = count;
if (*ppos != 0)
return -EINVAL;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (count == 0 || count > SMK_LONGLABEL)
return -EINVAL;
data = memdup_user(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
cp = smk_parse_smack(data, count);
if (IS_ERR(cp)) {
rc = PTR_ERR(cp);
goto out_data;
}
skp = smk_find_entry(cp);
if (skp == NULL)
goto out_cp;
rule_list = &skp->smk_rules;
rule_lock = &skp->smk_rules_lock;
mutex_lock(rule_lock);
list_for_each_entry_rcu(sp, rule_list, list)
sp->smk_access = 0;
mutex_unlock(rule_lock);
out_cp:
kfree(cp);
out_data:
kfree(data);
return rc;
}
static const struct file_operations smk_revoke_subj_ops = {
.write = smk_write_revoke_subj,
.read = simple_transaction_read,
.release = simple_transaction_release,
.llseek = generic_file_llseek,
};
/**
* smk_init_sysfs - initialize /sys/fs/smackfs
*
*/
static int smk_init_sysfs(void)
{
return sysfs_create_mount_point(fs_kobj, "smackfs");
}
/**
* smk_write_change_rule - write() for /smack/change-rule
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_write_change_rule(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/*
* Must have privilege.
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
return smk_write_rules_list(file, buf, count, ppos, NULL, NULL,
SMK_CHANGE_FMT);
}
static const struct file_operations smk_change_rule_ops = {
.write = smk_write_change_rule,
.read = simple_transaction_read,
.release = simple_transaction_release,
.llseek = generic_file_llseek,
};
/**
* smk_read_syslog - read() for smackfs/syslog
* @filp: file pointer, not actually used
* @buf: where to put the result
* @cn: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_syslog(struct file *filp, char __user *buf,
size_t cn, loff_t *ppos)
{
struct smack_known *skp;
ssize_t rc = -EINVAL;
int asize;
if (*ppos != 0)
return 0;
if (smack_syslog_label == NULL)
skp = &smack_known_star;
else
skp = smack_syslog_label;
asize = strlen(skp->smk_known) + 1;
if (cn >= asize)
rc = simple_read_from_buffer(buf, cn, ppos, skp->smk_known,
asize);
return rc;
}
/**
* smk_write_syslog - write() for smackfs/syslog
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_syslog(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char *data;
struct smack_known *skp;
int rc = count;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
skp = smk_import_entry(data, count);
if (IS_ERR(skp))
rc = PTR_ERR(skp);
else
smack_syslog_label = skp;
kfree(data);
return rc;
}
static const struct file_operations smk_syslog_ops = {
.read = smk_read_syslog,
.write = smk_write_syslog,
.llseek = default_llseek,
};
/*
* Seq_file read operations for /smack/relabel-self
*/
static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_start(s, pos, &tsp->smk_relabel);
}
static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct task_smack *tsp = smack_cred(current_cred());
return smk_seq_next(s, v, pos, &tsp->smk_relabel);
}
static int relabel_self_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_known_list_elem *sklep =
list_entry(list, struct smack_known_list_elem, list);
seq_puts(s, sklep->smk_label->smk_known);
seq_putc(s, ' ');
return 0;
}
static const struct seq_operations relabel_self_seq_ops = {
.start = relabel_self_seq_start,
.next = relabel_self_seq_next,
.show = relabel_self_seq_show,
.stop = smk_seq_stop,
};
/**
* smk_open_relabel_self - open() for /smack/relabel-self
* @inode: inode structure representing file
* @file: "relabel-self" file pointer
*
* Connect our relabel_self_seq_* operations with /smack/relabel-self
* file_operations
*/
static int smk_open_relabel_self(struct inode *inode, struct file *file)
{
return seq_open(file, &relabel_self_seq_ops);
}
/**
* smk_write_relabel_self - write() for /smack/relabel-self
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
*/
static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct task_smack *tsp = smack_cred(current_cred());
char *data;
int rc;
LIST_HEAD(list_tmp);
/*
* Must have privilege.
*/
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
/*
* Enough data must be present.
*/
if (*ppos != 0)
return -EINVAL;
data = memdup_user_nul(buf, count);
if (IS_ERR(data))
return PTR_ERR(data);
rc = smk_parse_label_list(data, &list_tmp);
kfree(data);
if (!rc || (rc == -EINVAL && list_empty(&list_tmp))) {
smk_destroy_label_list(&tsp->smk_relabel);
list_splice(&list_tmp, &tsp->smk_relabel);
return count;
}
smk_destroy_label_list(&list_tmp);
return rc;
}
static const struct file_operations smk_relabel_self_ops = {
.open = smk_open_relabel_self,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_relabel_self,
.release = seq_release,
};
/**
* smk_read_ptrace - read() for /smack/ptrace
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_ptrace(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[32];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d\n", smack_ptrace_rule);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_ptrace - write() for /smack/ptrace
* @file: file pointer
* @buf: data from user space
* @count: bytes sent
* @ppos: where to start - must be 0
*/
static ssize_t smk_write_ptrace(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char temp[32];
int i;
if (!smack_privileged(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0 || count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
if (i < SMACK_PTRACE_DEFAULT || i > SMACK_PTRACE_MAX)
return -EINVAL;
smack_ptrace_rule = i;
return count;
}
static const struct file_operations smk_ptrace_ops = {
.write = smk_write_ptrace,
.read = smk_read_ptrace,
.llseek = default_llseek,
};
/**
* smk_fill_super - fill the smackfs superblock
* @sb: the empty superblock
* @data: unused
* @silent: unused
*
* Fill in the well known entries for the smack filesystem
*
* Returns 0 on success, an error code on failure
*/
static int smk_fill_super(struct super_block *sb, void *data, int silent)
{
int rc;
static const struct tree_descr smack_files[] = {
[SMK_LOAD] = {
"load", &smk_load_ops, S_IRUGO|S_IWUSR},
[SMK_CIPSO] = {
"cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR},
[SMK_DOI] = {
"doi", &smk_doi_ops, S_IRUGO|S_IWUSR},
[SMK_DIRECT] = {
"direct", &smk_direct_ops, S_IRUGO|S_IWUSR},
[SMK_AMBIENT] = {
"ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR},
[SMK_NET4ADDR] = {
"netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
[SMK_ONLYCAP] = {
"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
[SMK_LOGGING] = {
"logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
[SMK_LOAD_SELF] = {
"load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO},
[SMK_ACCESSES] = {
"access", &smk_access_ops, S_IRUGO|S_IWUGO},
[SMK_MAPPED] = {
"mapped", &smk_mapped_ops, S_IRUGO|S_IWUSR},
[SMK_LOAD2] = {
"load2", &smk_load2_ops, S_IRUGO|S_IWUSR},
[SMK_LOAD_SELF2] = {
"load-self2", &smk_load_self2_ops, S_IRUGO|S_IWUGO},
[SMK_ACCESS2] = {
"access2", &smk_access2_ops, S_IRUGO|S_IWUGO},
[SMK_CIPSO2] = {
"cipso2", &smk_cipso2_ops, S_IRUGO|S_IWUSR},
[SMK_REVOKE_SUBJ] = {
"revoke-subject", &smk_revoke_subj_ops,
S_IRUGO|S_IWUSR},
[SMK_CHANGE_RULE] = {
"change-rule", &smk_change_rule_ops, S_IRUGO|S_IWUSR},
[SMK_SYSLOG] = {
"syslog", &smk_syslog_ops, S_IRUGO|S_IWUSR},
[SMK_PTRACE] = {
"ptrace", &smk_ptrace_ops, S_IRUGO|S_IWUSR},
#ifdef CONFIG_SECURITY_SMACK_BRINGUP
[SMK_UNCONFINED] = {
"unconfined", &smk_unconfined_ops, S_IRUGO|S_IWUSR},
#endif
#if IS_ENABLED(CONFIG_IPV6)
[SMK_NET6ADDR] = {
"ipv6host", &smk_net6addr_ops, S_IRUGO|S_IWUSR},
#endif /* CONFIG_IPV6 */
[SMK_RELABEL_SELF] = {
"relabel-self", &smk_relabel_self_ops,
S_IRUGO|S_IWUGO},
/* last one */
{""}
};
rc = simple_fill_super(sb, SMACK_MAGIC, smack_files);
if (rc != 0) {
printk(KERN_ERR "%s failed %d while creating inodes\n",
__func__, rc);
return rc;
}
return 0;
}
/**
* smk_mount - get the smackfs superblock
* @fs_type: passed along without comment
* @flags: passed along without comment
* @dev_name: passed along without comment
* @data: passed along without comment
*
* Just passes everything along.
*
* Returns what the lower level code does.
*/
static struct dentry *smk_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_single(fs_type, flags, data, smk_fill_super);
}
static struct file_system_type smk_fs_type = {
.name = "smackfs",
.mount = smk_mount,
.kill_sb = kill_litter_super,
};
static struct vfsmount *smackfs_mount;
static int __init smk_preset_netlabel(struct smack_known *skp)
{
skp->smk_netlabel.domain = skp->smk_known;
skp->smk_netlabel.flags =
NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
return smk_netlbl_mls(smack_cipso_direct, skp->smk_known,
&skp->smk_netlabel, strlen(skp->smk_known));
}
/**
* init_smk_fs - get the smackfs superblock
*
* register the smackfs
*
* Do not register smackfs if Smack wasn't enabled
* on boot. We can not put this method normally under the
* smack_init() code path since the security subsystem get
* initialized before the vfs caches.
*
* Returns true if we were not chosen on boot or if
* we were chosen and filesystem registration succeeded.
*/
static int __init init_smk_fs(void)
{
int err;
int rc;
if (smack_enabled == 0)
return 0;
err = smk_init_sysfs();
if (err)
printk(KERN_ERR "smackfs: sysfs mountpoint problem.\n");
err = register_filesystem(&smk_fs_type);
if (!err) {
smackfs_mount = kern_mount(&smk_fs_type);
if (IS_ERR(smackfs_mount)) {
printk(KERN_ERR "smackfs: could not mount!\n");
err = PTR_ERR(smackfs_mount);
smackfs_mount = NULL;
}
}
smk_cipso_doi();
smk_unlbl_ambient(NULL);
rc = smk_preset_netlabel(&smack_known_floor);
if (err == 0 && rc < 0)
err = rc;
rc = smk_preset_netlabel(&smack_known_hat);
if (err == 0 && rc < 0)
err = rc;
rc = smk_preset_netlabel(&smack_known_huh);
if (err == 0 && rc < 0)
err = rc;
rc = smk_preset_netlabel(&smack_known_star);
if (err == 0 && rc < 0)
err = rc;
rc = smk_preset_netlabel(&smack_known_web);
if (err == 0 && rc < 0)
err = rc;
return err;
}
__initcall(init_smk_fs);
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