// SPDX-License-Identifier: GPL-2.0+

#include <stdio.h>
#include <linux/dcbnl.h>
#include <libmnl/libmnl.h>
#include <getopt.h>

#include "dcb.h"
#include "mnl_utils.h"
#include "namespace.h"
#include "utils.h"
#include "version.h"

static int dcb_init(struct dcb *dcb)
{
	dcb->buf = malloc(MNL_SOCKET_BUFFER_SIZE);
	if (dcb->buf == NULL) {
		perror("Netlink buffer allocation");
		return -1;
	}

	dcb->nl = mnlu_socket_open(NETLINK_ROUTE);
	if (dcb->nl == NULL) {
		perror("Open netlink socket");
		goto err_socket_open;
	}

	new_json_obj_plain(dcb->json_output);
	return 0;

err_socket_open:
	free(dcb->buf);
	return -1;
}

static void dcb_fini(struct dcb *dcb)
{
	delete_json_obj_plain();
	mnl_socket_close(dcb->nl);
}

static struct dcb *dcb_alloc(void)
{
	struct dcb *dcb;

	dcb = calloc(1, sizeof(*dcb));
	if (!dcb)
		return NULL;
	return dcb;
}

static void dcb_free(struct dcb *dcb)
{
	free(dcb);
}

struct dcb_get_attribute {
	struct dcb *dcb;
	int attr;
	void *data;
	size_t data_len;
};

static int dcb_get_attribute_attr_ieee_cb(const struct nlattr *attr, void *data)
{
	struct dcb_get_attribute *ga = data;
	uint16_t len;

	if (mnl_attr_get_type(attr) != ga->attr)
		return MNL_CB_OK;

	len = mnl_attr_get_payload_len(attr);
	if (len != ga->data_len) {
		fprintf(stderr, "Wrong len %d, expected %zd\n", len, ga->data_len);
		return MNL_CB_ERROR;
	}

	memcpy(ga->data, mnl_attr_get_payload(attr), ga->data_len);
	return MNL_CB_STOP;
}

static int dcb_get_attribute_attr_cb(const struct nlattr *attr, void *data)
{
	if (mnl_attr_get_type(attr) != DCB_ATTR_IEEE)
		return MNL_CB_OK;

	return mnl_attr_parse_nested(attr, dcb_get_attribute_attr_ieee_cb, data);
}

static int dcb_get_attribute_cb(const struct nlmsghdr *nlh, void *data)
{
	return mnl_attr_parse(nlh, sizeof(struct dcbmsg), dcb_get_attribute_attr_cb, data);
}

static int dcb_set_attribute_attr_cb(const struct nlattr *attr, void *data)
{
	uint16_t len;
	uint8_t err;

	if (mnl_attr_get_type(attr) != DCB_ATTR_IEEE)
		return MNL_CB_OK;

	len = mnl_attr_get_payload_len(attr);
	if (len != 1) {
		fprintf(stderr, "Response attribute expected to have size 1, not %d\n", len);
		return MNL_CB_ERROR;
	}

	err = mnl_attr_get_u8(attr);
	if (err) {
		fprintf(stderr, "Error when attempting to set attribute: %s\n",
			strerror(err));
		return MNL_CB_ERROR;
	}

	return MNL_CB_STOP;
}

static int dcb_set_attribute_cb(const struct nlmsghdr *nlh, void *data)
{
	return mnl_attr_parse(nlh, sizeof(struct dcbmsg), dcb_set_attribute_attr_cb, data);
}

static int dcb_talk(struct dcb *dcb, struct nlmsghdr *nlh, mnl_cb_t cb, void *data)
{
	int ret;

	ret = mnl_socket_sendto(dcb->nl, nlh, nlh->nlmsg_len);
	if (ret < 0) {
		perror("mnl_socket_sendto");
		return -1;
	}

	return mnlu_socket_recv_run(dcb->nl, nlh->nlmsg_seq, dcb->buf, MNL_SOCKET_BUFFER_SIZE,
				    cb, data);
}

static struct nlmsghdr *dcb_prepare(struct dcb *dcb, const char *dev,
				    uint32_t nlmsg_type, uint8_t dcb_cmd)
{
	struct dcbmsg dcbm = {
		.cmd = dcb_cmd,
	};
	struct nlmsghdr *nlh;

	nlh = mnlu_msg_prepare(dcb->buf, nlmsg_type, NLM_F_REQUEST, &dcbm, sizeof(dcbm));
	mnl_attr_put_strz(nlh, DCB_ATTR_IFNAME, dev);
	return nlh;
}

int dcb_get_attribute(struct dcb *dcb, const char *dev, int attr, void *data, size_t data_len)
{
	struct dcb_get_attribute ga;
	struct nlmsghdr *nlh;
	int ret;

	nlh = dcb_prepare(dcb, dev, RTM_GETDCB, DCB_CMD_IEEE_GET);

	ga = (struct dcb_get_attribute) {
		.dcb = dcb,
		.attr = attr,
		.data = data,
		.data_len = data_len,
	};
	ret = dcb_talk(dcb, nlh, dcb_get_attribute_cb, &ga);
	if (ret) {
		perror("Attribute read");
		return ret;
	}
	return 0;
}

int dcb_set_attribute(struct dcb *dcb, const char *dev, int attr, const void *data, size_t data_len)
{
	struct nlmsghdr *nlh;
	struct nlattr *nest;
	int ret;

	nlh = dcb_prepare(dcb, dev, RTM_GETDCB, DCB_CMD_IEEE_SET);

	nest = mnl_attr_nest_start(nlh, DCB_ATTR_IEEE);
	mnl_attr_put(nlh, attr, data_len, data);
	mnl_attr_nest_end(nlh, nest);

	ret = dcb_talk(dcb, nlh, dcb_set_attribute_cb, NULL);
	if (ret) {
		perror("Attribute write");
		return ret;
	}
	return 0;
}

void dcb_print_array_u8(const __u8 *array, size_t size)
{
	SPRINT_BUF(b);
	size_t i;

	for (i = 0; i < size; i++) {
		snprintf(b, sizeof(b), "%zd:%%d ", i);
		print_uint(PRINT_ANY, NULL, b, array[i]);
	}
}

void dcb_print_array_kw(const __u8 *array, size_t array_size,
			const char *const kw[], size_t kw_size)
{
	SPRINT_BUF(b);
	size_t i;

	for (i = 0; i < array_size; i++) {
		__u8 emt = array[i];

		snprintf(b, sizeof(b), "%zd:%%s ", i);
		if (emt < kw_size && kw[emt])
			print_string(PRINT_ANY, NULL, b, kw[emt]);
		else
			print_string(PRINT_ANY, NULL, b, "???");
	}
}

void dcb_print_named_array(const char *json_name, const char *fp_name,
			   const __u8 *array, size_t size,
			   void (*print_array)(const __u8 *, size_t))
{
	open_json_array(PRINT_JSON, json_name);
	print_string(PRINT_FP, NULL, "%s ", fp_name);
	print_array(array, size);
	close_json_array(PRINT_JSON, json_name);
}

int dcb_parse_mapping(const char *what_key, __u32 key, __u32 max_key,
		      const char *what_value, __u32 value, __u32 max_value,
		      void (*set_array)(__u32 index, __u32 value, void *data),
		      void *set_array_data)
{
	bool is_all = key == (__u32) -1;

	if (!is_all && key > max_key) {
		fprintf(stderr, "In %s:%s mapping, %s is expected to be 0..%d\n",
			what_key, what_value, what_key, max_key);
		return -EINVAL;
	}

	if (value > max_value) {
		fprintf(stderr, "In %s:%s mapping, %s is expected to be 0..%d\n",
			what_key, what_value, what_value, max_value);
		return -EINVAL;
	}

	if (is_all) {
		for (key = 0; key <= max_key; key++)
			set_array(key, value, set_array_data);
	} else {
		set_array(key, value, set_array_data);
	}

	return 0;
}

void dcb_set_u8(__u32 key, __u32 value, void *data)
{
	__u8 *array = data;

	array[key] = value;
}

int dcb_cmd_parse_dev(struct dcb *dcb, int argc, char **argv,
		      int (*and_then)(struct dcb *dcb, const char *dev,
				      int argc, char **argv),
		      void (*help)(void))
{
	const char *dev;

	if (!argc || matches(*argv, "help") == 0) {
		help();
		return 0;
	} else if (matches(*argv, "dev") == 0) {
		NEXT_ARG();
		dev = *argv;
		if (check_ifname(dev)) {
			invarg("not a valid ifname", *argv);
			return -EINVAL;
		}
		NEXT_ARG_FWD();
		return and_then(dcb, dev, argc, argv);
	} else {
		fprintf(stderr, "Expected `dev DEV', not `%s'", *argv);
		help();
		return -EINVAL;
	}
}

static void dcb_help(void)
{
	fprintf(stderr,
		"Usage: dcb [ OPTIONS ] OBJECT { COMMAND | help }\n"
		"       dcb [ -f | --force ] { -b | --batch } filename [ -N | --Netns ] netnsname\n"
		"where  OBJECT :=\n"
		"       OPTIONS := [ -V | --Version | -j | --json | -p | --pretty | -v | --verbose ]\n");
}

static int dcb_cmd(struct dcb *dcb, int argc, char **argv)
{
	if (!argc || matches(*argv, "help") == 0) {
		dcb_help();
		return 0;
	}

	fprintf(stderr, "Object \"%s\" is unknown\n", *argv);
	return -ENOENT;
}

static int dcb_batch_cmd(int argc, char *argv[], void *data)
{
	struct dcb *dcb = data;

	return dcb_cmd(dcb, argc, argv);
}

static int dcb_batch(struct dcb *dcb, const char *name, bool force)
{
	return do_batch(name, force, dcb_batch_cmd, dcb);
}

int main(int argc, char **argv)
{
	static const struct option long_options[] = {
		{ "Version",		no_argument,		NULL, 'V' },
		{ "force",		no_argument,		NULL, 'f' },
		{ "batch",		required_argument,	NULL, 'b' },
		{ "json",		no_argument,		NULL, 'j' },
		{ "pretty",		no_argument,		NULL, 'p' },
		{ "Netns",		required_argument,	NULL, 'N' },
		{ "help",		no_argument,		NULL, 'h' },
		{ NULL, 0, NULL, 0 }
	};
	const char *batch_file = NULL;
	bool force = false;
	struct dcb *dcb;
	int opt;
	int err;
	int ret;

	dcb = dcb_alloc();
	if (!dcb) {
		fprintf(stderr, "Failed to allocate memory for dcb\n");
		return EXIT_FAILURE;
	}

	while ((opt = getopt_long(argc, argv, "b:c::fhjnpvN:V",
				  long_options, NULL)) >= 0) {

		switch (opt) {
		case 'V':
			printf("dcb utility, iproute2-%s\n", version);
			ret = EXIT_SUCCESS;
			goto dcb_free;
		case 'f':
			force = true;
			break;
		case 'b':
			batch_file = optarg;
			break;
		case 'j':
			dcb->json_output = true;
			break;
		case 'p':
			pretty = true;
			break;
		case 'N':
			if (netns_switch(optarg)) {
				ret = EXIT_FAILURE;
				goto dcb_free;
			}
			break;
		case 'h':
			dcb_help();
			return 0;
		default:
			fprintf(stderr, "Unknown option.\n");
			dcb_help();
			ret = EXIT_FAILURE;
			goto dcb_free;
		}
	}

	argc -= optind;
	argv += optind;

	err = dcb_init(dcb);
	if (err) {
		ret = EXIT_FAILURE;
		goto dcb_free;
	}

	if (batch_file)
		err = dcb_batch(dcb, batch_file, force);
	else
		err = dcb_cmd(dcb, argc, argv);

	if (err) {
		ret = EXIT_FAILURE;
		goto dcb_fini;
	}

	ret = EXIT_SUCCESS;

dcb_fini:
	dcb_fini(dcb);
dcb_free:
	dcb_free(dcb);

	return ret;
}