static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_member_sid(ssid, tsid, tclass, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
goto out;
}
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_change_sid(ssid, tsid, tclass, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT)
goto out;
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
u32 ssid, tsid;
u16 tclass;
struct av_decision avd;
ssize_t length;
length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
goto out;
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
security_compute_av_user(ssid, tsid, tclass, &avd);
length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
"%x %x %x %x %u %x",
avd.allowed, 0xffffffff,
avd.auditallow, avd.auditdeny,
avd.seqno, avd.flags);
out:
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
{
char *con = NULL, *user = NULL, *ptr;
u32 sid, *sids = NULL;
ssize_t length;
char *newcon;
int i, rc;
u32 len, nsids;
length = task_has_security(current, SECURITY__COMPUTE_USER);
if (length)
goto out;
length = -ENOMEM;
con = kzalloc(size + 1, GFP_KERNEL);
if (!con)
goto out;
length = -ENOMEM;
user = kzalloc(size + 1, GFP_KERNEL);
if (!user)
goto out;
length = -EINVAL;
if (sscanf(buf, "%s %s", con, user) != 2)
goto out;
length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
if (length)
goto out;
length = security_get_user_sids(sid, user, &sids, &nsids);
if (length)
goto out;
length = sprintf(buf, "%u", nsids) + 1;
ptr = buf + length;
for (i = 0; i < nsids; i++) {
rc = security_sid_to_context(sids[i], &newcon, &len);
if (rc) {
length = rc;
goto out;
}
if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
kfree(newcon);
length = -ERANGE;
goto out;
}
memcpy(ptr, newcon, len);
kfree(newcon);
ptr += len;
length += len;
}
out:
kfree(sids);
kfree(user);
kfree(con);
return length;
}
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
char *scon = NULL, *tcon = NULL;
char *namebuf = NULL, *objname = NULL;
u32 ssid, tsid, newsid;
u16 tclass;
ssize_t length;
char *newcon = NULL;
u32 len;
int nargs;
length = task_has_security(current, SECURITY__COMPUTE_CREATE);
if (length)
goto out;
length = -ENOMEM;
scon = kzalloc(size + 1, GFP_KERNEL);
if (!scon)
goto out;
length = -ENOMEM;
tcon = kzalloc(size + 1, GFP_KERNEL);
if (!tcon)
goto out;
length = -ENOMEM;
namebuf = kzalloc(size + 1, GFP_KERNEL);
if (!namebuf)
goto out;
length = -EINVAL;
nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
if (nargs < 3 || nargs > 4)
goto out;
if (nargs == 4) {
/*
* If and when the name of new object to be queried contains
* either whitespace or multibyte characters, they shall be
* encoded based on the percentage-encoding rule.
* If not encoded, the sscanf logic picks up only left-half
* of the supplied name; splitted by a whitespace unexpectedly.
*/
char *r, *w;
int c1, c2;
r = w = namebuf;
do {
c1 = *r++;
if (c1 == '+')
c1 = ' ';
else if (c1 == '%') {
c1 = hex_to_bin(*r++);
if (c1 < 0)
goto out;
c2 = hex_to_bin(*r++);
if (c2 < 0)
goto out;
c1 = (c1 << 4) | c2;
}
*w++ = c1;
} while (c1 != '\0');
objname = namebuf;
}
length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
if (length)
goto out;
length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
if (length)
goto out;
length = security_transition_sid_user(ssid, tsid, tclass,
objname, &newsid);
if (length)
goto out;
length = security_sid_to_context(newsid, &newcon, &len);
if (length)
goto out;
length = -ERANGE;
if (len > SIMPLE_TRANSACTION_LIMIT) {
printk(KERN_ERR "SELinux: %s: context size (%u) exceeds "
"payload max\n", __func__, len);
goto out;
}
memcpy(buf, newcon, len);
length = len;
out:
kfree(newcon);
kfree(namebuf);
kfree(tcon);
kfree(scon);
return length;
}
static ssize_t sel_write_validatetrans(struct file *file,
const char __user *buf,
size_t count, loff_t *ppos)
{
char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
char *req = NULL;
u32 osid, nsid, tsid;
u16 tclass;
int rc;
rc = task_has_security(current, SECURITY__VALIDATE_TRANS);
if (rc)
goto out;
rc = -ENOMEM;
if (count >= PAGE_SIZE)
goto out;
/* No partial writes. */
rc = -EINVAL;
if (*ppos != 0)
goto out;
rc = -ENOMEM;
req = kzalloc(count + 1, GFP_KERNEL);
if (!req)
goto out;
rc = -EFAULT;
if (copy_from_user(req, buf, count))
goto out;
rc = -ENOMEM;
oldcon = kzalloc(count + 1, GFP_KERNEL);
if (!oldcon)
goto out;
newcon = kzalloc(count + 1, GFP_KERNEL);
if (!newcon)
goto out;
taskcon = kzalloc(count + 1, GFP_KERNEL);
if (!taskcon)
goto out;
rc = -EINVAL;
if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
goto out;
rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
if (rc)
goto out;
rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
if (rc)
goto out;
rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
if (rc)
goto out;
rc = security_validate_transition_user(osid, nsid, tsid, tclass);
if (!rc)
rc = count;
out:
kfree(req);
kfree(oldcon);
kfree(newcon);
kfree(taskcon);
return rc;
}
