#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <pwd.h>
#include <netax25/axlib.h>
#include <netax25/axconfig.h>

#include "node.h"

long IdleTimeout	= 900L;		/* default to 15 mins */
long ConnTimeout	= 3600L;	/* default to 60 mins */
int ReConnectTo		= 0;
int ResolveAddrs       	= 0;
int LogLevel		= L_ERROR;
int EscChar		= 20;		/* CTRL-T */

char *HostName		= NULL;
char *NodeId		= "LinuxNode}";
char *NodePrompt	= "\n";
char *NrPort		= NULL;		/* first netrom port */

static unsigned long Permissions	= 0L;
static unsigned long LocalNet		= 0L;
static unsigned long LocalMask		= ~0L;
static char *HiddenPorts[32]		= {0};

/*
 * Return non-zero if `port' is a hidden port.
 */
int is_hidden(const char *port)
{
	int i;

	for (i = 0; HiddenPorts[i] != NULL && i < 31; i++)
		if (!strcmp(port, HiddenPorts[i]))
			return 1;
	return 0;
}

/*
 * Return non-zero if peer is on "local" or loopback network.
 */
static int is_local(unsigned long peer)
{
	return ((peer & LocalMask) == LocalNet) || ((peer & 0xff) == 127);
}

/*
 * Return non-zero if peer is on amprnet.
 */
static int is_ampr(unsigned long peer)
{
	return ((peer & 0xff) == 44);
}

/*
 * Convert NOS style width to a netmask in network byte order.
 */
static unsigned long bits_to_mask(int bits)
{
	return htonl(~0L << (32 - bits));
}

int check_perms(int what, unsigned long peer)
{
	if (what == PERM_TELNET) {
		if (is_local(peer)) {
			if (Permissions & PERM_TELNET_LOCAL)
				return 0;
		} else if (is_ampr(peer)) {
			if (Permissions & PERM_TELNET_AMPR)
				return 0;
		} else {
			if (Permissions & PERM_TELNET_INET)
				return 0;
		}
		return -1;
	}
	if ((Permissions & what) == 0) {
		return -1;
	}
	return 0;
}

/*
 * Read permissions file and return a password if needed or "*" if not.
 * If user access is denied return NULL.
 */
char *read_perms(struct user *up, unsigned long peer)
{
	FILE *fp;
	char line[256], *argv[32], *cp, *pw;
	int argc, n = 0;

	if ((fp = fopen(CONF_NODE_PERMS_FILE, "r")) == NULL) {
		node_perror(CONF_NODE_PERMS_FILE, errno);
		return NULL;
	}
	if ((cp = strchr(up->call, '-')) != NULL)
		*cp = 0;
	pw = NULL;
	while (fgets(line, 256, fp) != NULL) {
		n++;
		argc = parse_args(argv, line);
		if (argc == 0 || *argv[0] == '#')
			continue;
		if (argc != 5) {
			node_msg("Configuration error");
			log(L_ERROR, "Syntax error in permission file at line %d", n);
			break;
		}
		if (strcmp(argv[0], "*") && strcasecmp(argv[0], up->call))
			continue;
		switch (up->ul_type) {
		case AF_AX25:
			if (!strcmp(argv[1], "*"))
				break;
			if (!strcasecmp(argv[1], "ax25"))
				break;
			continue;
		case AF_NETROM:
			if (!strcmp(argv[1], "*"))
				break;
			if (!strcasecmp(argv[1], "netrom"))
				break;
			continue;
		case AF_ROSE:
			if (!strcmp(argv[1], "*"))
				break;
			if (!strcasecmp(argv[1], "rose"))
				break;
			continue;
		case AF_INET:
			if (!strcmp(argv[1], "*"))
				break;
			if (!strcasecmp(argv[1], "local") && is_local(peer))
				break;
			if (!strcasecmp(argv[1], "ampr") && is_ampr(peer))
				break;
			if (!strcasecmp(argv[1], "inet") && !is_local(peer) && !is_ampr(peer))
				break;
			continue;
		case AF_UNSPEC:
			if (!strcmp(argv[1], "*"))
				break;
			if (!strcasecmp(argv[1], "host"))
				break;
			continue;
		}
		if (up->ul_type == AF_AX25) {
			if (strcmp(argv[2], "*") && strcmp(argv[2], up->ul_name))
				continue;
		}
		if (cp != NULL)
			*cp = '-';
		if ((Permissions = strtoul(argv[4], NULL, 10)) != 0)
			pw = strdup(argv[3]);
		break;
	}
	fclose(fp);
	return pw;
}

static int do_alias(int argc, char **argv)
{
	struct cmd *new;
	int len = 0;

	if (argc < 3)
		return -1;
	if ((new = calloc(1, sizeof(struct cmd))) == NULL) {
		node_perror("do_alias: malloc", errno);
		return -2;
	}
	new->name = strdup(argv[1]);
	while (isupper(new->name[len]))
		len++;
	/* Ok. So they can't read... */
	if (len == 0) {
		strupr(new->name);
		len = strlen(new->name);
	}
	new->len = len;
	new->command = strdup(argv[2]);
	new->type = CMD_ALIAS;
	insert_cmd(&Nodecmds, new);
	return 0;
}

static int do_loglevel(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	LogLevel = atoi(argv[1]);
	return 0;
}

int get_escape(char *s)
{
	int escape;
	char *endptr[1];

	if (isdigit(*s)) {
		escape = strtol(s, endptr, 0);
		if (**endptr)
			return -2;
		else
			return escape;
	}
	if (strlen(s) == 1)
		return *s;
	if (strlen(s) == 2 && *s == '^')
		return (toupper(*++s) - 'A' + 1);
	if (strcasecmp(s, "off") == 0 || strcmp(s, "-1") == 0)
		return -1;
	return -2;
}

static int do_escapechar(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	EscChar = get_escape(argv[1]);
	if (EscChar < -1 || EscChar > 255) {
		node_msg("Configuration error");
		log(L_ERROR, "do_escapechar: Invalid escape character %s",
		    argv[1]);
		return -2;
	}
	return 0;
}

static int do_idletimeout(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	IdleTimeout = atol(argv[1]);
	return 0;
}

static int do_conntimeout(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	ConnTimeout = atol(argv[1]);
	return 0;
}

static int do_hostname(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	HostName = strdup(argv[1]);
	return 0;
}

static int do_localnet(int argc, char **argv)
{
	char *cp;

	if (argc < 2)
		return -1;
	if ((cp = strchr(argv[1], '/')) != NULL) {
		*cp = 0;
		LocalMask = bits_to_mask(atoi(++cp));
	}
	LocalNet = inet_addr(argv[1]);
	LocalNet &= LocalMask;
	return 0;
}

static int do_reconnect(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	if (!strcasecmp(argv[1], "on"))
		ReConnectTo = 1;
	else
		ReConnectTo = 0;
	return 0;
}

static int do_resolveaddrs(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	if (!strcasecmp(argv[1], "on"))
		ResolveAddrs = 1;
	else
		ResolveAddrs = 0;
	return 0;
}

static int do_hiddenports(int argc, char **argv)
{
	int i;

	if (argc < 2)
		return -1;
	for (i = 1; i < argc && i < 31; i++) {
		if (ax25_config_get_dev(argv[i]) == NULL) {
			node_msg("Configuration error");
			log(L_ERROR, "do_hiddenports: invalid port %s", argv[i]);
			return -2;
		}
		HiddenPorts[i - 1] = strdup(argv[i]);
	}
	HiddenPorts[i - 1] = NULL;
	return 0;
}

static int do_extcmd(int argc, char **argv)
{
	struct cmd *new;
	struct passwd *pw;
	char buf[1024];
	int i, len;

	if (argc < 6)
		return -1;
	if ((new = calloc(1, sizeof(struct cmd))) == NULL) {
		node_perror("do_extcmd: malloc", errno);
		return -2;
	}
	new->name = strdup(argv[1]);
	len = 0;
	while (isupper(new->name[len]))
		len++;
	/* Ok. So they can't read... */
	if (len == 0) {
		strupr(new->name);
		len = strlen(new->name);
	}
	new->len = len;
	new->flags = atoi(argv[2]);
	if ((pw = getpwnam(argv[3])) == NULL) {
		node_msg("Configuration error");
		log(L_ERROR, "do_extcmd: Unknown user %s", argv[3]);
		return -2;
	}
	new->uid = pw->pw_uid;
	new->gid = pw->pw_gid;
	new->path = strdup(argv[4]);
	len = 0;
	for (i = 0; argv[i + 5] != NULL; i++)
		len += sprintf(&buf[len], "\"%s\" ", argv[i + 5]);
	new->command = strdup(buf);
	new->type = CMD_EXTERNAL;
	insert_cmd(&Nodecmds, new);
	return 0;
}

static int do_nodeid(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	NodeId = strdup(argv[1]);
	return 0;
}

static int do_nodeprompt(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	NodePrompt = strdup(argv[1]);
	return 0;
}

static int do_nrport(int argc, char **argv)
{
	if (argc < 2)
		return -1;
	NrPort = strdup(argv[1]);
	return 0;
}

int read_config(void)
{
	struct cmd *cfg_cmds = NULL;
	FILE *fp;
	char line[256];
	int ret, n = 0;

	add_internal_cmd(&cfg_cmds, "alias",        0, do_alias);
	add_internal_cmd(&cfg_cmds, "conntimeout",  0, do_conntimeout);
	add_internal_cmd(&cfg_cmds, "escapechar",   0, do_escapechar);
	add_internal_cmd(&cfg_cmds, "extcmd",       0, do_extcmd);
	add_internal_cmd(&cfg_cmds, "hiddenports",  0, do_hiddenports);
	add_internal_cmd(&cfg_cmds, "hostname",     0, do_hostname);
	add_internal_cmd(&cfg_cmds, "idletimeout",  0, do_idletimeout);
	add_internal_cmd(&cfg_cmds, "localnet",     0, do_localnet);
	add_internal_cmd(&cfg_cmds, "loglevel",     0, do_loglevel);
	add_internal_cmd(&cfg_cmds, "nodeid",       0, do_nodeid);
	add_internal_cmd(&cfg_cmds, "nodeprompt",   0, do_nodeprompt);
	add_internal_cmd(&cfg_cmds, "nrport",       0, do_nrport);
	add_internal_cmd(&cfg_cmds, "reconnect",    0, do_reconnect);
	add_internal_cmd(&cfg_cmds, "resolveaddrs", 0, do_resolveaddrs);

	if ((fp = fopen(CONF_NODE_FILE, "r")) == NULL) {
		node_perror(CONF_NODE_FILE, errno);
		return -1;
	}
	while (fgets(line, 256, fp) != NULL) {
		n++;
		ret = cmdparse(cfg_cmds, line);
		if (ret == -1) {
			node_msg("Configuration error");
			log(L_ERROR, "Syntax error in config file at line %d: %s", n, line);
		}
		if (ret < 0) {
			fclose(fp);
			return -1;
		}
	}
	fclose(fp);
	free_cmdlist(cfg_cmds);
	cfg_cmds = NULL;
	return 0;
}