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smackfs.c
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/*
* Copyright (C) 2007 Casey Schaufler <[email protected]>
*
* 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 <[email protected]>
* Ahmed S. Darwish <[email protected]>
*
* Special thanks to the authors of selinuxfs.
*
* Karl MacMillan <[email protected]>
* James Morris <[email protected]>
*
*/
#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/netlabel.h>
#include <net/cipso_ipv4.h>
#include <linux/seq_file.h>
#include <linux/ctype.h>
#include <linux/audit.h>
#include "smack.h"
/*
* 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_NETLBLADDR = 8, /* single label hosts */
SMK_ONLYCAP = 9, /* the only "capable" label */
SMK_LOGGING = 10, /* logging */
};
/*
* List locks
*/
static DEFINE_MUTEX(smack_list_lock);
static DEFINE_MUTEX(smack_cipso_lock);
static DEFINE_MUTEX(smack_ambient_lock);
static DEFINE_MUTEX(smk_netlbladdr_lock);
/*
* This is the "ambient" label for network traffic.
* If it isn't somehow marked, use this.
* It can be reset via smackfs/ambient
*/
char *smack_net_ambient = smack_known_floor.smk_known;
/*
* 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;
/*
* Unless a process is running with this label even
* having CAP_MAC_OVERRIDE isn't enough to grant
* privilege to violate MAC policy. If no label is
* designated (the NULL case) capabilities apply to
* everyone. It is expected that the hat (^) label
* will be used if any label is used.
*/
char *smack_onlycap;
/*
* 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_netlbladdr_list);
LIST_HEAD(smack_rule_list);
static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
const char *smack_cipso_option = SMACK_CIPSO_OPTION;
#define SEQ_READ_FINISHED 1
/*
* 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_ACCESS "rwxa"
#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
/**
* smk_netlabel_audit_set - fill a netlbl_audit struct
* @nap: structure to fill
*/
static void smk_netlabel_audit_set(struct netlbl_audit *nap)
{
nap->loginuid = audit_get_loginuid(current);
nap->sessionid = audit_get_sessionid(current);
nap->secid = smack_to_secid(current_security());
}
/*
* Values for parsing single label host rules
* "1.2.3.4 X"
* "192.168.138.129/32 abcdefghijklmnopqrstuvw"
*/
#define SMK_NETLBLADDRMIN 9
#define SMK_NETLBLADDRMAX 42
/*
* Seq_file read operations for /smack/load
*/
static void *load_seq_start(struct seq_file *s, loff_t *pos)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smack_rule_list))
return NULL;
return smack_rule_list.next;
}
static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
if (list_is_last(list, &smack_rule_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
static int load_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp =
list_entry(list, struct smack_rule, list);
seq_printf(s, "%s %s", (char *)srp->smk_subject,
(char *)srp->smk_object);
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 == 0)
seq_putc(s, '-');
seq_putc(s, '\n');
return 0;
}
static void load_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations load_seq_ops = {
.start = load_seq_start,
.next = load_seq_next,
.show = load_seq_show,
.stop = load_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_set_access - add a rule to the rule list
* @srp: the new rule to add
*
* 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_rule *srp)
{
struct smack_rule *sp;
int ret = 0;
int found;
mutex_lock(&smack_list_lock);
found = 0;
list_for_each_entry_rcu(sp, &smack_rule_list, list) {
if (sp->smk_subject == srp->smk_subject &&
sp->smk_object == srp->smk_object) {
found = 1;
sp->smk_access = srp->smk_access;
break;
}
}
if (found == 0)
list_add_rcu(&srp->list, &smack_rule_list);
mutex_unlock(&smack_list_lock);
return ret;
}
/**
* 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
*
* Get one smack access rule from above.
* The format is exactly:
* char subject[SMK_LABELLEN]
* char object[SMK_LABELLEN]
* char access[SMK_ACCESSLEN]
*
* writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes.
*/
static ssize_t smk_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_rule *rule;
char *data;
int rc = -EINVAL;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
*/
if (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0 || count != SMK_LOADLEN)
return -EINVAL;
data = kzalloc(count, GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
if (copy_from_user(data, buf, count) != 0) {
rc = -EFAULT;
goto out;
}
rule = kzalloc(sizeof(*rule), GFP_KERNEL);
if (rule == NULL) {
rc = -ENOMEM;
goto out;
}
rule->smk_subject = smk_import(data, 0);
if (rule->smk_subject == NULL)
goto out_free_rule;
rule->smk_object = smk_import(data + SMK_LABELLEN, 0);
if (rule->smk_object == NULL)
goto out_free_rule;
rule->smk_access = 0;
switch (data[SMK_LABELLEN + SMK_LABELLEN]) {
case '-':
break;
case 'r':
case 'R':
rule->smk_access |= MAY_READ;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 1]) {
case '-':
break;
case 'w':
case 'W':
rule->smk_access |= MAY_WRITE;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 2]) {
case '-':
break;
case 'x':
case 'X':
rule->smk_access |= MAY_EXEC;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 3]) {
case '-':
break;
case 'a':
case 'A':
rule->smk_access |= MAY_APPEND;
break;
default:
goto out_free_rule;
}
rc = smk_set_access(rule);
if (!rc)
rc = count;
goto out;
out_free_rule:
kfree(rule);
out:
kfree(data);
return rc;
}
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);
}
rc = netlbl_cfg_unlbl_map_add(smack_net_ambient, 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)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smack_known_list))
return NULL;
return smack_known_list.next;
}
static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
/*
* labels with no associated cipso value wont be printed
* in cipso_seq_show
*/
if (list_is_last(list, &smack_known_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
/*
* 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(list, struct smack_known, list);
struct smack_cipso *scp = skp->smk_cipso;
char *cbp;
char sep = '/';
int cat = 1;
int i;
unsigned char m;
if (scp == NULL)
return 0;
seq_printf(s, "%s %3d", (char *)&skp->smk_known, scp->smk_level);
cbp = scp->smk_catset;
for (i = 0; i < SMK_LABELLEN; i++)
for (m = 0x80; m != 0; m >>= 1) {
if (m & cbp[i]) {
seq_printf(s, "%c%d", sep, cat);
sep = ',';
}
cat++;
}
seq_putc(s, '\n');
return 0;
}
static void cipso_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations cipso_seq_ops = {
.start = cipso_seq_start,
.stop = cipso_seq_stop,
.next = cipso_seq_next,
.show = cipso_seq_show,
};
/**
* 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_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)
{
struct smack_known *skp;
struct smack_cipso *scp = NULL;
char mapcatset[SMK_LABELLEN];
int maplevel;
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 (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX)
return -EINVAL;
data = kzalloc(count + 1, GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
if (copy_from_user(data, buf, count) != 0) {
rc = -EFAULT;
goto unlockedout;
}
/* labels cannot begin with a '-' */
if (data[0] == '-') {
rc = -EINVAL;
goto unlockedout;
}
data[count] = '\0';
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 (skp == NULL)
goto out;
rule += SMK_LABELLEN;
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 (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, "%d", &cat);
if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL)
goto out;
smack_catset_bit(cat, mapcatset);
}
if (skp->smk_cipso == NULL) {
scp = kzalloc(sizeof(struct smack_cipso), GFP_KERNEL);
if (scp == NULL) {
rc = -ENOMEM;
goto out;
}
}
spin_lock_bh(&skp->smk_cipsolock);
if (scp == NULL)
scp = skp->smk_cipso;
else
skp->smk_cipso = scp;
scp->smk_level = maplevel;
memcpy(scp->smk_catset, mapcatset, sizeof(mapcatset));
spin_unlock_bh(&skp->smk_cipsolock);
rc = count;
out:
mutex_unlock(&smack_cipso_lock);
unlockedout:
kfree(data);
return rc;
}
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/netlabel
*/
static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smk_netlbladdr_list))
return NULL;
return smk_netlbladdr_list.next;
}
static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
if (list_is_last(list, &smk_netlbladdr_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
#define BEBITS (sizeof(__be32) * 8)
/*
* Print host/label pairs
*/
static int netlbladdr_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smk_netlbladdr *skp =
list_entry(list, struct smk_netlbladdr, list);
unsigned char *hp = (char *) &skp->smk_host.sin_addr.s_addr;
int maskn;
u32 temp_mask = be32_to_cpu(skp->smk_mask.s_addr);
for (maskn = 0; temp_mask; temp_mask <<= 1, maskn++);
seq_printf(s, "%u.%u.%u.%u/%d %s\n",
hp[0], hp[1], hp[2], hp[3], maskn, skp->smk_label);
return 0;
}
static void netlbladdr_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations netlbladdr_seq_ops = {
.start = netlbladdr_seq_start,
.stop = netlbladdr_seq_stop,
.next = netlbladdr_seq_next,
.show = netlbladdr_seq_show,
};
/**
* smk_open_netlbladdr - open() for /smack/netlabel
* @inode: inode structure representing file
* @file: "netlabel" file pointer
*
* Connect our netlbladdr_seq_* operations with /smack/netlabel
* file_operations
*/
static int smk_open_netlbladdr(struct inode *inode, struct file *file)
{
return seq_open(file, &netlbladdr_seq_ops);
}
/**
* smk_netlbladdr_insert
* @new : netlabel to insert
*
* This helper insert netlabel in the smack_netlbladdrs list
* sorted by netmask length (longest to smallest)
* locked by &smk_netlbladdr_lock in smk_write_netlbladdr
*
*/
static void smk_netlbladdr_insert(struct smk_netlbladdr *new)
{
struct smk_netlbladdr *m, *m_next;
if (list_empty(&smk_netlbladdr_list)) {
list_add_rcu(&new->list, &smk_netlbladdr_list);
return;
}
m = list_entry_rcu(smk_netlbladdr_list.next,
struct smk_netlbladdr, list);
/* the comparison '>' is a bit hacky, but works */
if (new->smk_mask.s_addr > m->smk_mask.s_addr) {
list_add_rcu(&new->list, &smk_netlbladdr_list);
return;
}
list_for_each_entry_rcu(m, &smk_netlbladdr_list, list) {
if (list_is_last(&m->list, &smk_netlbladdr_list)) {
list_add_rcu(&new->list, &m->list);
return;
}
m_next = list_entry_rcu(m->list.next,
struct smk_netlbladdr, list);
if (new->smk_mask.s_addr > m_next->smk_mask.s_addr) {
list_add_rcu(&new->list, &m->list);
return;
}
}
}
/**
* smk_write_netlbladdr - 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 netlbladdr per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smk_netlbladdr *skp;
struct sockaddr_in newname;
char smack[SMK_LABELLEN];
char *sp;
char data[SMK_NETLBLADDRMAX + 1];
char *host = (char *)&newname.sin_addr.s_addr;
int rc;
struct netlbl_audit audit_info;
struct in_addr mask;
unsigned int m;
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 (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_NETLBLADDRMIN || count > SMK_NETLBLADDRMAX)
return -EINVAL;
if (copy_from_user(data, buf, count) != 0)
return -EFAULT;
data[count] = '\0';
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%d %s",
&host[0], &host[1], &host[2], &host[3], &m, smack);
if (rc != 6) {
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
&host[0], &host[1], &host[2], &host[3], smack);
if (rc != 5)
return -EINVAL;
m = BEBITS;
}
if (m > BEBITS)
return -EINVAL;
/* if smack begins with '-', its an option, don't import it */
if (smack[0] != '-') {
sp = smk_import(smack, 0);
if (sp == NULL)
return -EINVAL;
} else {
/* check known options */
if (strcmp(smack, smack_cipso_option) == 0)
sp = (char *)smack_cipso_option;
else
return -EINVAL;
}
for (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_netlbladdr_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(skp, &smk_netlbladdr_list, list) {
if (skp->smk_host.sin_addr.s_addr == nsa &&
skp->smk_mask.s_addr == mask.s_addr) {
found = 1;
break;
}
}
smk_netlabel_audit_set(&audit_info);
if (found == 0) {
skp = kzalloc(sizeof(*skp), GFP_KERNEL);
if (skp == NULL)
rc = -ENOMEM;
else {
rc = 0;
skp->smk_host.sin_addr.s_addr = newname.sin_addr.s_addr;
skp->smk_mask.s_addr = mask.s_addr;
skp->smk_label = sp;
smk_netlbladdr_insert(skp);
}
} else {
/* we delete the unlabeled entry, only if the previous label
* wasnt the special CIPSO option */
if (skp->smk_label != smack_cipso_option)
rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
&skp->smk_host.sin_addr, &skp->smk_mask,
PF_INET, &audit_info);
else
rc = 0;
skp->smk_label = sp;
}
/*
* 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 && sp != smack_cipso_option)
rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
&skp->smk_host.sin_addr, &skp->smk_mask, PF_INET,
smack_to_secid(skp->smk_label), &audit_info);
if (rc == 0)
rc = count;
mutex_unlock(&smk_netlbladdr_lock);
return rc;
}
static const struct file_operations smk_netlbladdr_ops = {
.open = smk_open_netlbladdr,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_netlbladdr,
.release = seq_release,
};
/**
* 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 (!capable(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,
};
/**
* 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