networking/udhcp/files.c - busybox - Git at Google

 /*
  * files.c -- DHCP server file manipulation *
  * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
  */

 #include <sys/socket.h>
 #include <arpa/inet.h>
 #include <string.h>
 #include <stdlib.h>
 #include <time.h>
 #include <ctype.h>

 #include "dhcpd.h"
 #include "files.h"
 #include "options.h"
 #include "common.h"

 /* on these functions, make sure you datatype matches */
 static int read_ip(const char *line, void *arg)
 {
 	struct in_addr *addr = arg;
 	struct hostent *host;
 	int retval = 1;

 	if (!inet_aton(line, addr)) {
 		if ((host = gethostbyname(line)))
 			addr->s_addr = *((unsigned long *) host->h_addr_list[0]);
 		else retval = 0;
 	}
 	return retval;
 }


 static int read_str(const char *line, void *arg)
 {
 	char **dest = arg;

 	if (*dest) free(*dest);
 	*dest = strdup(line);

 	return 1;
 }


 static int read_u32(const char *line, void *arg)
 {
 	u_int32_t *dest = arg;
 	char *endptr;
 	*dest = strtoul(line, &endptr, 0);
 	return endptr[0] == '\0';
 }


 static int read_yn(const char *line, void *arg)
 {
 	char *dest = arg;
 	int retval = 1;

 	if (!strcasecmp("yes", line))
 		*dest = 1;
 	else if (!strcasecmp("no", line))
 		*dest = 0;
 	else retval = 0;

 	return retval;
 }

 #define READ_CONFIG_BUF_SIZE 512        /* domainname may have 254 chars */

 /* read a dhcp option and add it to opt_list */
 static int read_opt(const char *const_line, void *arg)
 {
     char line[READ_CONFIG_BUF_SIZE];
 	struct option_set **opt_list = arg;
 	char *opt, *val, *endptr;
     struct dhcp_option *option;
     int retval = 0, length;
     char buffer[256];                       /* max opt length */
 	u_int16_t result_u16;
 	u_int32_t result_u32;
     void *valptr;

     if ((opt = strtok(strcpy(line, const_line), " \t="))) {

 	for (option = options; option->code; option++)
 		if (!strcasecmp(option->name, opt))
 			break;

 	if (option->code) do {
 		val = strtok(NULL, ", \t");
 		if(!val)
 			break;
 			length = option_lengths[option->flags & TYPE_MASK];
 		valptr = NULL;
 			switch (option->flags & TYPE_MASK) {
 			case OPTION_IP:
 				retval = read_ip(val, buffer);
 				break;
 			case OPTION_IP_PAIR:
 				retval = read_ip(val, buffer);
 				if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
 				if (retval) retval = read_ip(val, buffer + 4);
 				break;
 			case OPTION_STRING:
 				length = strlen(val);
 				if (length > 0) {
 					if (length > 254) length = 254;
 				endptr = buffer + length;
 				endptr[0] = 0;
 				valptr = val;
 				}
 				break;
 			case OPTION_BOOLEAN:
 				retval = read_yn(val, buffer);
 				break;
 			case OPTION_U8:
 				buffer[0] = strtoul(val, &endptr, 0);
 			valptr = buffer;
 				break;
 			case OPTION_U16:
 				result_u16 = htons(strtoul(val, &endptr, 0));
 			valptr = &result_u16;
 				break;
 			case OPTION_S16:
 				result_u16 = htons(strtol(val, &endptr, 0));
 			valptr = &result_u16;
 				break;
 			case OPTION_U32:
 				result_u32 = htonl(strtoul(val, &endptr, 0));
 			valptr = &result_u32;
 				break;
 			case OPTION_S32:
 				result_u32 = htonl(strtol(val, &endptr, 0));
 			valptr = &result_u32;
 				break;
 			default:
 			retval = 0;
 				break;
 			}
 		if(valptr) {
 			memcpy(buffer, valptr, length);
 			retval = (endptr[0] == '\0');
 		}
 			if (retval)
 				attach_option(opt_list, option, buffer, length);
 		else
 			break;
 	} while (option->flags & OPTION_LIST);
     }
 	return retval;
 }


 static const struct config_keyword keywords[] = {
 	/* keyword      handler   variable address              default     */
 	{"start",	read_ip,  &(server_config.start),	"192.168.0.20"},
 	{"end",		read_ip,  &(server_config.end),		"192.168.0.254"},
 	{"interface",	read_str, &(server_config.interface),	"eth0"},
 	{"option",	read_opt, &(server_config.options),	""},
 	{"opt",		read_opt, &(server_config.options),	""},
 	{"max_leases",	read_u32, &(server_config.max_leases),	"254"},
 	{"remaining",	read_yn,  &(server_config.remaining),	"yes"},
 	{"auto_time",	read_u32, &(server_config.auto_time),	"7200"},
 	{"decline_time",read_u32, &(server_config.decline_time),"3600"},
 	{"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
 	{"offer_time",	read_u32, &(server_config.offer_time),	"60"},
 	{"min_lease",	read_u32, &(server_config.min_lease),	"60"},
 	{"lease_file",  read_str, &(server_config.lease_file),  leases_file},
 	{"pidfile",	read_str, &(server_config.pidfile),	"/var/run/udhcpd.pid"},
 	{"notify_file", read_str, &(server_config.notify_file),	""},
 	{"siaddr",	read_ip,  &(server_config.siaddr),	"0.0.0.0"},
 	{"sname",	read_str, &(server_config.sname),	""},
 	{"boot_file",	read_str, &(server_config.boot_file),	""},
 	/*ADDME: static lease */
 	{"",		NULL, 	  NULL,				""}
 };


 int read_config(const char *file)
 {
 	FILE *in;
 	char buffer[READ_CONFIG_BUF_SIZE], orig[READ_CONFIG_BUF_SIZE];
 	char *token, *line;
 	int i;

 	for (i = 0; keywords[i].keyword[0]; i++)
 		if (keywords[i].def[0])
 			keywords[i].handler(keywords[i].def, keywords[i].var);

 	if (!(in = fopen(file, "r"))) {
 		LOG(LOG_ERR, "unable to open config file: %s", file);
 		return 0;
 	}

 	while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
 		if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
 		strcpy(orig, buffer);
 		if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';
 		token = strtok(buffer, " \t");
 		if(!token)
 			continue;
 		line = strtok(NULL, "");
 		if(!line)
 			continue;
 		while(*line == '=' || isspace(*line))
 		line++;
 		/* eat trailing whitespace */
 		for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
 		line[i] = '\0';
 		if (*line == '\0')
 			continue;

 		for (i = 0; keywords[i].keyword[0]; i++)
 			if (!strcasecmp(token, keywords[i].keyword))
 				if (!keywords[i].handler(line, keywords[i].var)) {
 					LOG(LOG_ERR, "unable to parse '%s'", orig);
 					/* reset back to the default value */
 					keywords[i].handler(keywords[i].def, keywords[i].var);
 				}
 	}
 	fclose(in);
 	return 1;
 }


 void write_leases(void)
 {
 	FILE *fp;
 	unsigned int i;
 	char buf[255];
 	time_t curr = time(0);
 	unsigned long lease_time;

 	if (!(fp = fopen(server_config.lease_file, "w"))) {
 		LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file);
 		return;
 	}

 	for (i = 0; i < server_config.max_leases; i++) {
 		struct dhcpOfferedAddr lease;
 		if (leases[i].yiaddr != 0) {
 			if (server_config.remaining) {
 				if (lease_expired(&(leases[i])))
 					lease_time = 0;
 				else lease_time = leases[i].expires - curr;
 			} else lease_time = leases[i].expires;
 			lease.expires = htonl(lease_time);
 			memcpy(lease.chaddr, leases[i].chaddr, 16);
 			lease.yiaddr = leases[i].yiaddr;
 			fwrite(leases, sizeof(lease), 1, fp);
 		}
 	}
 	fclose(fp);

 	if (server_config.notify_file) {
 		sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
 		system(buf);
 	}
 }


 void read_leases(const char *file)
 {
 	FILE *fp;
 	unsigned int i = 0;
 	struct dhcpOfferedAddr lease;

 	if (!(fp = fopen(file, "r"))) {
 		LOG(LOG_ERR, "Unable to open %s for reading", file);
 		return;
 	}

 	while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) {
 		/* ADDME: is it a static lease */
 		if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
 			lease.expires = ntohl(lease.expires);
 			if (!server_config.remaining) lease.expires -= time(0);
 			if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
 				LOG(LOG_WARNING, "Too many leases while loading %s\n", file);
 				break;
 			}
 			i++;
 		}
 	}
 	DEBUG(LOG_INFO, "Read %d leases", i);
 	fclose(fp);
 }
	/*
	* files.c -- DHCP server file manipulation *
	* Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
	*/

	#include <sys/socket.h>
	#include <arpa/inet.h>
	#include <string.h>
	#include <stdlib.h>
	#include <time.h>
	#include <ctype.h>

	#include "dhcpd.h"
	#include "files.h"
	#include "options.h"
	#include "common.h"

	/* on these functions, make sure you datatype matches */
	static int read_ip(const char line, void arg)
	{
	struct in_addr *addr = arg;
	struct hostent *host;
	int retval = 1;

	if (!inet_aton(line, addr)) {
	if ((host = gethostbyname(line)))
	addr->s_addr = ((unsigned long ) host->h_addr_list[0]);
	else retval = 0;
	}
	return retval;
	}


	static int read_str(const char line, void arg)
	{
	char **dest = arg;

	if (dest) free(dest);
	*dest = strdup(line);

	return 1;
	}


	static int read_u32(const char line, void arg)
	{
	u_int32_t *dest = arg;
	char *endptr;
	*dest = strtoul(line, &endptr, 0);
	return endptr[0] == '\0';
	}


	static int read_yn(const char line, void arg)
	{
	char *dest = arg;
	int retval = 1;

	if (!strcasecmp("yes", line))
	*dest = 1;
	else if (!strcasecmp("no", line))
	*dest = 0;
	else retval = 0;

	return retval;
	}

	#define READ_CONFIG_BUF_SIZE 512 /* domainname may have 254 chars */

	/* read a dhcp option and add it to opt_list */
	static int read_opt(const char const_line, void arg)
	{
	char line[READ_CONFIG_BUF_SIZE];
	struct option_set **opt_list = arg;
	char opt, val, *endptr;
	struct dhcp_option *option;
	int retval = 0, length;
	char buffer[256]; /* max opt length */
	u_int16_t result_u16;
	u_int32_t result_u32;
	void *valptr;

	if ((opt = strtok(strcpy(line, const_line), " \t="))) {

	for (option = options; option->code; option++)
	if (!strcasecmp(option->name, opt))
	break;

	if (option->code) do {
	val = strtok(NULL, ", \t");
	if(!val)
	break;
	length = option_lengths[option->flags & TYPE_MASK];
	valptr = NULL;
	switch (option->flags & TYPE_MASK) {
	case OPTION_IP:
	retval = read_ip(val, buffer);
	break;
	case OPTION_IP_PAIR:
	retval = read_ip(val, buffer);
	if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
	if (retval) retval = read_ip(val, buffer + 4);
	break;
	case OPTION_STRING:
	length = strlen(val);
	if (length > 0) {
	if (length > 254) length = 254;
	endptr = buffer + length;
	endptr[0] = 0;
	valptr = val;
	}
	break;
	case OPTION_BOOLEAN:
	retval = read_yn(val, buffer);
	break;
	case OPTION_U8:
	buffer[0] = strtoul(val, &endptr, 0);
	valptr = buffer;
	break;
	case OPTION_U16:
	result_u16 = htons(strtoul(val, &endptr, 0));
	valptr = &result_u16;
	break;
	case OPTION_S16:
	result_u16 = htons(strtol(val, &endptr, 0));
	valptr = &result_u16;
	break;
	case OPTION_U32:
	result_u32 = htonl(strtoul(val, &endptr, 0));
	valptr = &result_u32;
	break;
	case OPTION_S32:
	result_u32 = htonl(strtol(val, &endptr, 0));
	valptr = &result_u32;
	break;
	default:
	retval = 0;
	break;
	}
	if(valptr) {
	memcpy(buffer, valptr, length);
	retval = (endptr[0] == '\0');
	}
	if (retval)
	attach_option(opt_list, option, buffer, length);
	else
	break;
	} while (option->flags & OPTION_LIST);
	}
	return retval;
	}


	static const struct config_keyword keywords[] = {
	/* keyword handler variable address default */
	{"start", read_ip, &(server_config.start), "192.168.0.20"},
	{"end", read_ip, &(server_config.end), "192.168.0.254"},
	{"interface", read_str, &(server_config.interface), "eth0"},
	{"option", read_opt, &(server_config.options), ""},
	{"opt", read_opt, &(server_config.options), ""},
	{"max_leases", read_u32, &(server_config.max_leases), "254"},
	{"remaining", read_yn, &(server_config.remaining), "yes"},
	{"auto_time", read_u32, &(server_config.auto_time), "7200"},
	{"decline_time",read_u32, &(server_config.decline_time),"3600"},
	{"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
	{"offer_time", read_u32, &(server_config.offer_time), "60"},
	{"min_lease", read_u32, &(server_config.min_lease), "60"},
	{"lease_file", read_str, &(server_config.lease_file), leases_file},
	{"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"},
	{"notify_file", read_str, &(server_config.notify_file), ""},
	{"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
	{"sname", read_str, &(server_config.sname), ""},
	{"boot_file", read_str, &(server_config.boot_file), ""},
	/ADDME: static lease /
	{"", NULL, NULL, ""}
	};


	int read_config(const char *file)
	{
	FILE *in;
	char buffer[READ_CONFIG_BUF_SIZE], orig[READ_CONFIG_BUF_SIZE];
	char token, line;
	int i;

	for (i = 0; keywords[i].keyword[0]; i++)
	if (keywords[i].def[0])
	keywords[i].handler(keywords[i].def, keywords[i].var);

	if (!(in = fopen(file, "r"))) {
	LOG(LOG_ERR, "unable to open config file: %s", file);
	return 0;
	}

	while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
	if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
	strcpy(orig, buffer);
	if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';
	token = strtok(buffer, " \t");
	if(!token)
	continue;
	line = strtok(NULL, "");
	if(!line)
	continue;
	while(line == '=' \|\| isspace(line))
	line++;
	/* eat trailing whitespace */
	for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
	line[i] = '\0';
	if (*line == '\0')
	continue;

	for (i = 0; keywords[i].keyword[0]; i++)
	if (!strcasecmp(token, keywords[i].keyword))
	if (!keywords[i].handler(line, keywords[i].var)) {
	LOG(LOG_ERR, "unable to parse '%s'", orig);
	/* reset back to the default value */
	keywords[i].handler(keywords[i].def, keywords[i].var);
	}
	}
	fclose(in);
	return 1;
	}


	void write_leases(void)
	{
	FILE *fp;
	unsigned int i;
	char buf[255];
	time_t curr = time(0);
	unsigned long lease_time;

	if (!(fp = fopen(server_config.lease_file, "w"))) {
	LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file);
	return;
	}

	for (i = 0; i < server_config.max_leases; i++) {
	struct dhcpOfferedAddr lease;
	if (leases[i].yiaddr != 0) {
	if (server_config.remaining) {
	if (lease_expired(&(leases[i])))
	lease_time = 0;
	else lease_time = leases[i].expires - curr;
	} else lease_time = leases[i].expires;
	lease.expires = htonl(lease_time);
	memcpy(lease.chaddr, leases[i].chaddr, 16);
	lease.yiaddr = leases[i].yiaddr;
	fwrite(leases, sizeof(lease), 1, fp);
	}
	}
	fclose(fp);

	if (server_config.notify_file) {
	sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
	system(buf);
	}
	}


	void read_leases(const char *file)
	{
	FILE *fp;
	unsigned int i = 0;
	struct dhcpOfferedAddr lease;

	if (!(fp = fopen(file, "r"))) {
	LOG(LOG_ERR, "Unable to open %s for reading", file);
	return;
	}

	while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) {
	/* ADDME: is it a static lease */
	if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
	lease.expires = ntohl(lease.expires);
	if (!server_config.remaining) lease.expires -= time(0);
	if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
	LOG(LOG_WARNING, "Too many leases while loading %s\n", file);
	break;
	}
	i++;
	}
	}
	DEBUG(LOG_INFO, "Read %d leases", i);
	fclose(fp);
	}