ssize_t nvdimm_security_store()

in security.c [500:558]

• 56 lines of code
• 21 McCabe index (conditional complexity)

ssize_t nvdimm_security_store(struct device *dev, const char *buf, size_t len)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);
	ssize_t rc;
	char cmd[SEC_CMD_SIZE+1], keystr[KEY_ID_SIZE+1],
		nkeystr[KEY_ID_SIZE+1];
	unsigned int key, newkey;
	int i;

	rc = sscanf(buf, "%"__stringify(SEC_CMD_SIZE)"s"
			" %"__stringify(KEY_ID_SIZE)"s"
			" %"__stringify(KEY_ID_SIZE)"s",
			cmd, keystr, nkeystr);
	if (rc < 1)
		return -EINVAL;
	for (i = 0; i < ARRAY_SIZE(ops); i++)
		if (sysfs_streq(cmd, ops[i].name))
			break;
	if (i >= ARRAY_SIZE(ops))
		return -EINVAL;
	if (ops[i].args > 1)
		rc = kstrtouint(keystr, 0, &key);
	if (rc >= 0 && ops[i].args > 2)
		rc = kstrtouint(nkeystr, 0, &newkey);
	if (rc < 0)
		return rc;

	if (i == OP_FREEZE) {
		dev_dbg(dev, "freeze\n");
		rc = nvdimm_security_freeze(nvdimm);
	} else if (i == OP_DISABLE) {
		dev_dbg(dev, "disable %u\n", key);
		rc = security_disable(nvdimm, key);
	} else if (i == OP_UPDATE || i == OP_MASTER_UPDATE) {
		dev_dbg(dev, "%s %u %u\n", ops[i].name, key, newkey);
		rc = security_update(nvdimm, key, newkey, i == OP_UPDATE
				? NVDIMM_USER : NVDIMM_MASTER);
	} else if (i == OP_ERASE || i == OP_MASTER_ERASE) {
		dev_dbg(dev, "%s %u\n", ops[i].name, key);
		if (atomic_read(&nvdimm->busy)) {
			dev_dbg(dev, "Unable to secure erase while DIMM active.\n");
			return -EBUSY;
		}
		rc = security_erase(nvdimm, key, i == OP_ERASE
				? NVDIMM_USER : NVDIMM_MASTER);
	} else if (i == OP_OVERWRITE) {
		dev_dbg(dev, "overwrite %u\n", key);
		if (atomic_read(&nvdimm->busy)) {
			dev_dbg(dev, "Unable to overwrite while DIMM active.\n");
			return -EBUSY;
		}
		rc = security_overwrite(nvdimm, key);
	} else
		return -EINVAL;

	if (rc == 0)
		rc = len;
	return rc;
}