static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
{
	char *scon, *tcon;
	u32 ssid, tsid, newsid;
	u16 tclass;
	ssize_t length;
	char *newcon;
	u32 len;

	length = task_has_security(current, SECURITY__COMPUTE_CREATE);
	if (length)
		return length;

	length = -ENOMEM;
	scon = kzalloc(size+1, GFP_KERNEL);
	if (!scon)
		return length;

	tcon = kzalloc(size+1, GFP_KERNEL);
	if (!tcon)
		goto out;

	length = -EINVAL;
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
		goto out2;

	length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
	if (length < 0)
		goto out2;
	length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
	if (length < 0)
		goto out2;

	length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
	if (length < 0)
		goto out2;

	length = security_sid_to_context(newsid, &newcon, &len);
	if (length < 0)
		goto out2;

	if (len > SIMPLE_TRANSACTION_LIMIT) {
		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
		length = -ERANGE;
		goto out3;
	}

	memcpy(buf, newcon, len);
	length = len;
out3:
	kfree(newcon);
out2:
	kfree(tcon);
out:
	kfree(scon);
	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_to_sid(scon, strlen(scon) + 1, &ssid);
	if (length)
		goto out;

	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
	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_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;
	char format[32];

	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;
	snprintf(format, sizeof(format), "%%%ds %%%ds %%hu %%%ds", size, size, size);
	nargs = sscanf(buf, format, scon, tcon, &tclass, namebuf);
	if (nargs < 3 || nargs > 4)
		goto out;
	if (nargs == 4) {
		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_to_sid(scon, strlen(scon) + 1, &ssid);
	if (length)
		goto out;

	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
	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;
}
Exemple #4
0
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)
		objname = namebuf;

	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
	if (length)
		goto out;

	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
	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;
}