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- /* dhcp.c - DHCP client for dynamic network configuration.
- *
- * Copyright 2012 Madhur Verma <mad.flexi@gmail.com>
- * Copyright 2013 Kyungwan Han <asura321@gmail.com>
- *
- * Not in SUSv4.
- USE_DHCP(NEWTOY(dhcp, "V:H:F:x*r:O*A#<0=20T#<0=3t#<0=3s:p:i:SBRCaovqnbf", TOYFLAG_SBIN|TOYFLAG_ROOTONLY))
- config DHCP
- bool "dhcp"
- default n
- help
- usage: dhcp [-fbnqvoCRB] [-i IFACE] [-r IP] [-s PROG] [-p PIDFILE]
- [-H HOSTNAME] [-V VENDOR] [-x OPT:VAL] [-O OPT]
- Configure network dynamically using DHCP.
- -i Interface to use (default eth0)
- -p Create pidfile
- -s Run PROG at DHCP events (default /usr/share/dhcp/default.script)
- -B Request broadcast replies
- -t Send up to N discover packets
- -T Pause between packets (default 3 seconds)
- -A Wait N seconds after failure (default 20)
- -f Run in foreground
- -b Background if lease is not obtained
- -n Exit if lease is not obtained
- -q Exit after obtaining lease
- -R Release IP on exit
- -S Log to syslog too
- -a Use arping to validate offered address
- -O Request option OPT from server (cumulative)
- -o Don't request any options (unless -O is given)
- -r Request this IP address
- -x OPT:VAL Include option OPT in sent packets (cumulative)
- -F Ask server to update DNS mapping for NAME
- -H Send NAME as client hostname (default none)
- -V VENDOR Vendor identifier (default 'toybox VERSION')
- -C Don't send MAC as client identifier
- -v Verbose
- Signals:
- USR1 Renew current lease
- USR2 Release current lease
- */
- #define FOR_dhcp
- #include "toys.h"
- // TODO: headers not in posix:
- #include <netinet/ip.h>
- #include <netinet/udp.h>
- #include <netpacket/packet.h>
- #include <linux/filter.h> //FIXME: linux specific. fix for other OS ports
- #include <linux/if_ether.h>
- GLOBALS(
- char *iface;
- char *pidfile;
- char *script;
- long retries;
- long timeout;
- long tryagain;
- struct arg_list *req_opt;
- char *req_ip;
- struct arg_list *pkt_opt;
- char *fdn_name;
- char *hostname;
- char *vendor_cls;
- )
- #define STATE_INIT 0
- #define STATE_REQUESTING 1
- #define STATE_BOUND 2
- #define STATE_RENEWING 3
- #define STATE_REBINDING 4
- #define STATE_RENEW_REQUESTED 5
- #define STATE_RELEASED 6
- #define BOOTP_BROADCAST 0x8000
- #define DHCP_MAGIC 0x63825363
- #define DHCP_REQUEST 1
- #define DHCP_REPLY 2
- #define DHCP_HTYPE_ETHERNET 1
- #define DHCPC_SERVER_PORT 67
- #define DHCPC_CLIENT_PORT 68
- #define DHCPDISCOVER 1
- #define DHCPOFFER 2
- #define DHCPREQUEST 3
- #define DHCPACK 5
- #define DHCPNAK 6
- #define DHCPRELEASE 7
- #define DHCP_OPTION_PADDING 0x00
- #define DHCP_OPTION_SUBNET_MASK 0x01
- #define DHCP_OPTION_ROUTER 0x03
- #define DHCP_OPTION_DNS_SERVER 0x06
- #define DHCP_OPTION_HOST_NAME 0x0c
- #define DHCP_OPTION_BROADCAST 0x1c
- #define DHCP_OPTION_REQ_IPADDR 0x32
- #define DHCP_OPTION_LEASE_TIME 0x33
- #define DHCP_OPTION_OVERLOAD 0x34
- #define DHCP_OPTION_MSG_TYPE 0x35
- #define DHCP_OPTION_SERVER_ID 0x36
- #define DHCP_OPTION_REQ_LIST 0x37
- #define DHCP_OPTION_MAX_SIZE 0x39
- #define DHCP_OPTION_CLIENTID 0x3D
- #define DHCP_OPTION_VENDOR 0x3C
- #define DHCP_OPTION_FQDN 0x51
- #define DHCP_OPTION_END 0xFF
- #define DHCP_NUM8 (1<<8)
- #define DHCP_NUM16 (1<<9)
- #define DHCP_NUM32 DHCP_NUM16 | DHCP_NUM8
- #define DHCP_STRING (1<<10)
- #define DHCP_STRLST (1<<11)
- #define DHCP_IP (1<<12)
- #define DHCP_IPLIST (1<<13)
- #define DHCP_IPPLST (1<<14)
- #define DHCP_STCRTS (1<<15)
- #define LOG_SILENT 0x0
- #define LOG_CONSOLE 0x1
- #define LOG_SYSTEM 0x2
- #define MODE_OFF 0
- #define MODE_RAW 1
- #define MODE_APP 2
- static void (*dbg)(char *format, ...);
- static void dummy(char *format, ...){
- return;
- }
- typedef struct dhcpc_result_s {
- struct in_addr serverid;
- struct in_addr ipaddr;
- struct in_addr netmask;
- struct in_addr dnsaddr;
- struct in_addr default_router;
- uint32_t lease_time;
- } dhcpc_result_t;
- typedef struct __attribute__((packed)) dhcp_msg_s {
- uint8_t op;
- uint8_t htype;
- uint8_t hlen;
- uint8_t hops;
- uint32_t xid;
- uint16_t secs;
- uint16_t flags;
- uint32_t ciaddr;
- uint32_t yiaddr;
- uint32_t nsiaddr;
- uint32_t ngiaddr;
- uint8_t chaddr[16];
- uint8_t sname[64];
- uint8_t file[128];
- uint32_t cookie;
- uint8_t options[308];
- } dhcp_msg_t;
- typedef struct __attribute__((packed)) dhcp_raw_s {
- struct iphdr iph;
- struct udphdr udph;
- dhcp_msg_t dhcp;
- } dhcp_raw_t;
- typedef struct dhcpc_state_s {
- uint8_t macaddr[6];
- char *iface;
- int ifindex;
- int sockfd;
- int status;
- int mode;
- uint32_t mask;
- struct in_addr ipaddr;
- struct in_addr serverid;
- dhcp_msg_t pdhcp;
- } dhcpc_state_t;
- typedef struct option_val_s {
- char *key;
- uint16_t code;
- void *val;
- size_t len;
- } option_val_t;
- struct fd_pair { int rd; int wr; };
- static uint32_t xid;
- static dhcpc_state_t *state;
- static struct fd_pair sigfd;
- uint8_t bmacaddr[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
- int set = 1;
- uint8_t infomode = LOG_CONSOLE;
- uint8_t raw_opt[29];
- int raw_optcount = 0;
- struct arg_list *x_opt;
- in_addr_t server = 0;
- static option_val_t *msgopt_list = NULL;
- static option_val_t options_list[] = {
- {"lease" , DHCP_NUM32 | 0x33, NULL, 0},
- {"subnet" , DHCP_IP | 0x01, NULL, 0},
- {"broadcast" , DHCP_IP | 0x1c, NULL, 0},
- {"router" , DHCP_IP | 0x03, NULL, 0},
- {"ipttl" , DHCP_NUM8 | 0x17, NULL, 0},
- {"mtu" , DHCP_NUM16 | 0x1a, NULL, 0},
- {"hostname" , DHCP_STRING | 0x0c, NULL, 0},
- {"domain" , DHCP_STRING | 0x0f, NULL, 0},
- {"search" , DHCP_STRLST | 0x77, NULL, 0},
- {"nisdomain" , DHCP_STRING | 0x28, NULL, 0},
- {"timezone" , DHCP_NUM32 | 0x02, NULL, 0},
- {"tftp" , DHCP_STRING | 0x42, NULL, 0},
- {"bootfile" , DHCP_STRING | 0x43, NULL, 0},
- {"bootsize" , DHCP_NUM16 | 0x0d, NULL, 0},
- {"rootpath" , DHCP_STRING | 0x11, NULL, 0},
- {"wpad" , DHCP_STRING | 0xfc, NULL, 0},
- {"serverid" , DHCP_IP | 0x36, NULL, 0},
- {"message" , DHCP_STRING | 0x38, NULL, 0},
- {"vlanid" , DHCP_NUM32 | 0x84, NULL, 0},
- {"vlanpriority" , DHCP_NUM32 | 0x85, NULL, 0},
- {"dns" , DHCP_IPLIST | 0x06, NULL, 0},
- {"wins" , DHCP_IPLIST | 0x2c, NULL, 0},
- {"nissrv" , DHCP_IPLIST | 0x29, NULL, 0},
- {"ntpsrv" , DHCP_IPLIST | 0x2a, NULL, 0},
- {"lprsrv" , DHCP_IPLIST | 0x09, NULL, 0},
- {"swapsrv" , DHCP_IP | 0x10, NULL, 0},
- {"routes" , DHCP_STCRTS | 0x21, NULL, 0},
- {"staticroutes" , DHCP_STCRTS | 0x79, NULL, 0},
- {"msstaticroutes" , DHCP_STCRTS | 0xf9, NULL, 0},
- };
- static struct sock_filter filter_instr[] = {
- BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9),
- BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 0, 6),
- BPF_STMT(BPF_LD|BPF_H|BPF_ABS, 6),
- BPF_JUMP(BPF_JMP|BPF_JSET|BPF_K, 0x1fff, 4, 0),
- BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), BPF_STMT(BPF_LD|BPF_H|BPF_IND, 2),
- BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 68, 0, 1),
- BPF_STMT(BPF_RET|BPF_K, 0xffffffff), BPF_STMT(BPF_RET|BPF_K, 0),
- };
- static struct sock_fprog filter_prog = {
- .len = ARRAY_LEN(filter_instr),
- .filter = (struct sock_filter *) filter_instr,
- };
- // calculate options size.
- static int dhcp_opt_size(uint8_t *optionptr)
- {
- int i = 0;
- for(;optionptr[i] != 0xff; i++) if(optionptr[i] != 0x00) i += optionptr[i + 1] + 2 -1;
- return i;
- }
- // calculates checksum for dhcp messages.
- static uint16_t dhcp_checksum(void *addr, int count)
- {
- int32_t sum = 0;
- uint16_t tmp = 0, *source = (uint16_t *)addr;
- while (count > 1) {
- sum += *source++;
- count -= 2;
- }
- if (count > 0) {
- *(uint8_t*)&tmp = *(uint8_t*)source;
- sum += tmp;
- }
- while (sum >> 16) sum = (sum & 0xffff) + (sum >> 16);
- return ~sum;
- }
- // gets information of INTERFACE and updates IFINDEX, MAC and IP
- static int get_interface( char *interface, int *ifindex, uint32_t *oip, uint8_t *mac)
- {
- struct ifreq req;
- struct sockaddr_in *ip;
- int fd = xsocket(AF_INET, SOCK_RAW, IPPROTO_RAW);
- req.ifr_addr.sa_family = AF_INET;
- xstrncpy(req.ifr_name, interface, IFNAMSIZ);
- req.ifr_name[IFNAMSIZ-1] = '\0';
- xioctl(fd, SIOCGIFFLAGS, &req);
- if (!(req.ifr_flags & IFF_UP)) return -1;
- if (oip) {
- xioctl(fd, SIOCGIFADDR, &req);
- ip = (struct sockaddr_in*) &req.ifr_addr;
- dbg("IP %s\n", inet_ntoa(ip->sin_addr));
- *oip = ntohl(ip->sin_addr.s_addr);
- }
- if (ifindex) {
- xioctl(fd, SIOCGIFINDEX, &req);
- dbg("Adapter index %d\n", req.ifr_ifindex);
- *ifindex = req.ifr_ifindex;
- }
- if (mac) {
- xioctl(fd, SIOCGIFHWADDR, &req);
- memcpy(mac, req.ifr_hwaddr.sa_data, 6);
- dbg("MAC %02x:%02x:%02x:%02x:%02x:%02x\n", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
- }
- close(fd);
- return 0;
- }
- /*
- *logs messeges to syslog or console
- *opening the log is still left with applet.
- *FIXME: move to more relevent lib. probably libc.c
- */
- static void infomsg(uint8_t infomode, char *s, ...)
- {
- int used;
- char *msg;
- va_list p, t;
- if (infomode == LOG_SILENT) return;
- va_start(p, s);
- va_copy(t, p);
- used = vsnprintf(NULL, 0, s, t);
- used++;
- va_end(t);
- msg = xmalloc(used);
- vsnprintf(msg, used, s, p);
- va_end(p);
- if (infomode & LOG_SYSTEM) syslog(LOG_INFO, "%s", msg);
- if (infomode & LOG_CONSOLE) printf("%s\n", msg);
- free(msg);
- }
- /*
- * Writes self PID in file PATH
- * FIXME: libc implementation only writes in /var/run
- * this is more generic as some implemenation may provide
- * arguments to write in specific file. as dhcpd does.
- */
- static void write_pid(char *path)
- {
- int pidfile = open(path, O_CREAT | O_WRONLY | O_TRUNC, 0666);
- if (pidfile > 0) {
- char pidbuf[12];
- sprintf(pidbuf, "%u", (unsigned)getpid());
- write(pidfile, pidbuf, strlen(pidbuf));
- close(pidfile);
- }
- }
- // String STR to UINT32 conversion strored in VAR
- static long strtou32( char *str)
- {
- char *endptr = NULL;
- int base = 10;
- errno=0;
- if (str[0]=='0' && (str[1]=='x' || str[1]=='X')) {
- base = 16;
- str+=2;
- }
- long ret_val = strtol(str, &endptr, base);
- if (errno) return -1;
- else if (endptr && (*endptr!='\0'||endptr == str)) return -1;
- return ret_val;
- }
- // IP String STR to binary data.
- static int striptovar( char *str, void *var)
- {
- in_addr_t addr;
- if(!str) error_exit("NULL address string.");
- addr = inet_addr(str);
- if(addr == -1) error_exit("Wrong address %s.",str );
- *((uint32_t*)(var)) = (uint32_t)addr;
- return 0;
- }
- // String to dhcp option conversion
- static int strtoopt( char *str, uint8_t optonly)
- {
- char *option, *valstr, *grp, *tp;
- long optcode = 0, convtmp;
- uint16_t flag = 0;
- uint32_t mask, nip, router;
- int count, size = ARRAY_LEN(options_list);
- if (!*str) return 0;
- option = strtok((char*)str, ":");
- if (!option) return -1;
- dbg("-x option : %s ", option);
- optcode = strtou32(option);
- if (optcode > 0 && optcode < 256) { // raw option
- for (count = 0; count < size; count++) {
- if ((options_list[count].code & 0X00FF) == optcode) {
- flag = (options_list[count].code & 0XFF00);
- break;
- }
- }
- if (count == size) error_exit("Obsolete OR Unknown Option : %s", option);
- } else { // string option
- for (count = 0; count < size; count++) {
- if (!strcmp(options_list[count].key, option)) {
- flag = (options_list[count].code & 0XFF00);
- optcode = (options_list[count].code & 0X00FF);
- break;
- }
- }
- if (count == size) error_exit("Obsolete OR Unknown Option : %s", option);
- }
- if (!flag || !optcode) return -1;
- if (optonly) return optcode;
- valstr = strtok(NULL, "\n");
- if (!valstr) error_exit("option %s has no value defined.\n", option);
- dbg(" value : %-20s \n ", valstr);
- switch (flag) {
- case DHCP_NUM32:
- options_list[count].len = sizeof(uint32_t);
- options_list[count].val = xmalloc(sizeof(uint32_t));
- convtmp = strtou32(valstr);
- if (convtmp < 0) error_exit("Invalid/wrong formatted number %s", valstr);
- convtmp = htonl(convtmp);
- memcpy(options_list[count].val, &convtmp, sizeof(uint32_t));
- break;
- case DHCP_NUM16:
- options_list[count].len = sizeof(uint16_t);
- options_list[count].val = xmalloc(sizeof(uint16_t));
- convtmp = strtou32(valstr);
- if (convtmp < 0) error_exit("Invalid/malformed number %s", valstr);
- convtmp = htons(convtmp);
- memcpy(options_list[count].val, &convtmp, sizeof(uint16_t));
- break;
- case DHCP_NUM8:
- options_list[count].len = sizeof(uint8_t);
- options_list[count].val = xmalloc(sizeof(uint8_t));
- convtmp = strtou32(valstr);
- if (convtmp < 0) error_exit("Invalid/malformed number %s", valstr);
- memcpy(options_list[count].val, &convtmp, sizeof(uint8_t));
- break;
- case DHCP_IP:
- options_list[count].len = sizeof(uint32_t);
- options_list[count].val = xmalloc(sizeof(uint32_t));
- striptovar(valstr, options_list[count].val);
- break;
- case DHCP_STRING:
- options_list[count].len = strlen(valstr);
- options_list[count].val = strdup(valstr);
- break;
- case DHCP_IPLIST:
- while(valstr){
- options_list[count].val = xrealloc(options_list[count].val, options_list[count].len + sizeof(uint32_t));
- striptovar(valstr, ((uint8_t*)options_list[count].val)+options_list[count].len);
- options_list[count].len += sizeof(uint32_t);
- valstr = strtok(NULL," \t");
- }
- break;
- case DHCP_STRLST:
- case DHCP_IPPLST:
- break;
- case DHCP_STCRTS:
- /* Option binary format:
- * mask [one byte, 0..32]
- * ip [0..4 bytes depending on mask]
- * router [4 bytes]
- * may be repeated
- * staticroutes 10.0.0.0/8 10.127.0.1, 10.11.12.0/24 10.11.12.1
- */
- grp = strtok(valstr, ",");;
- while(grp){
- while(*grp == ' ' || *grp == '\t') grp++;
- tp = strchr(grp, '/');
- if (!tp) error_exit("malformed static route option");
- *tp = '\0';
- mask = strtol(++tp, &tp, 10);
- if (striptovar(grp, (uint8_t*)&nip) < 0) error_exit("malformed static route option");
- while(*tp == ' ' || *tp == '\t' || *tp == '-') tp++;
- if (striptovar(tp, (uint8_t*)&router) < 0) error_exit("malformed static route option");
- options_list[count].val = xrealloc(options_list[count].val, options_list[count].len + 1 + mask/8 + 4);
- memcpy(((uint8_t*)options_list[count].val)+options_list[count].len, &mask, 1);
- options_list[count].len += 1;
- memcpy(((uint8_t*)options_list[count].val)+options_list[count].len, &nip, mask/8);
- options_list[count].len += mask/8;
- memcpy(((uint8_t*)options_list[count].val)+options_list[count].len, &router, 4);
- options_list[count].len += 4;
- tp = NULL;
- grp = strtok(NULL, ",");
- }
- break;
- }
- return 0;
- }
- // Creates environment pointers from RES to use in script
- static int fill_envp(dhcpc_result_t *res)
- {
- struct in_addr temp;
- int size = ARRAY_LEN(options_list), count, ret = -1;
- ret = setenv("interface", state->iface, 1);
- if (!res) return ret;
- if (res->ipaddr.s_addr) {
- temp.s_addr = htonl(res->ipaddr.s_addr);
- ret = setenv("ip", inet_ntoa(temp), 1);
- if (ret) return ret;
- }
- if (msgopt_list) {
- for (count = 0; count < size; count++) {
- if ((msgopt_list[count].len == 0) || (msgopt_list[count].val == NULL)) continue;
- ret = setenv(msgopt_list[count].key, (char*)msgopt_list[count].val, 1);
- if (ret) return ret;
- }
- }
- return ret;
- }
- // Executes Script NAME.
- static void run_script(dhcpc_result_t *res, char *name)
- {
- volatile int error = 0;
- pid_t pid;
- char *argv[3];
- struct stat sts;
- char *script = (toys.optflags & FLAG_s) ? TT.script
- : "/usr/share/dhcp/default.script";
- if (stat(script, &sts) == -1 && errno == ENOENT) return;
- if (fill_envp(res)) {
- dbg("Failed to create environment variables.");
- return;
- }
- dbg("Executing %s %s\n", script, name);
- argv[0] = (char*) script;
- argv[1] = (char*) name;
- argv[2] = NULL;
- fflush(NULL);
- pid = vfork();
- if (pid < 0) {
- dbg("Fork failed.\n");
- return;
- }
- if (!pid) {
- execvp(argv[0], argv);
- error = errno;
- _exit(111);
- }
- if (error) {
- waitpid(pid, NULL,0);
- errno = error;
- perror_msg("script exec failed");
- }
- dbg("script complete.\n");
- }
- // returns a randome ID
- static uint32_t getxid(void)
- {
- uint32_t randnum;
- int fd = xopenro("/dev/urandom");
- // TODO xreadfile
- xreadall(fd, &randnum, sizeof(randnum));
- xclose(fd);
- return randnum;
- }
- // opens socket in raw mode.
- static int mode_raw(void)
- {
- state->mode = MODE_OFF;
- struct sockaddr_ll sock;
- if (state->sockfd > 0) close(state->sockfd);
- dbg("Opening raw socket on ifindex %d\n", state->ifindex);
- state->sockfd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
- if (state->sockfd < 0) {
- dbg("MODE RAW : socket fail ERROR : %d\n", state->sockfd);
- return -1;
- }
- dbg("Got raw socket fd %d\n", state->sockfd);
- memset(&sock, 0, sizeof(sock));
- sock.sll_family = AF_PACKET;
- sock.sll_protocol = htons(ETH_P_IP);
- sock.sll_ifindex = state->ifindex;
- if (bind(state->sockfd, (struct sockaddr *) &sock, sizeof(sock))) {
- dbg("MODE RAW : bind fail.\n");
- close(state->sockfd);
- return -1;
- }
- state->mode = MODE_RAW;
- if (setsockopt(state->sockfd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog, sizeof(filter_prog)) < 0)
- dbg("MODE RAW : filter attach fail.\n");
- dbg("MODE RAW : success\n");
- return 0;
- }
- // opens UDP socket
- static int mode_app(void)
- {
- struct sockaddr_in addr;
- struct ifreq ifr;
- state->mode = MODE_OFF;
- if (state->sockfd > 0) close(state->sockfd);
- dbg("Opening listen socket on *:%d %s\n", DHCPC_CLIENT_PORT, state->iface);
- state->sockfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
- if (state->sockfd < 0) {
- dbg("MODE APP : socket fail ERROR: %d\n", state->sockfd);
- return -1;
- }
- setsockopt(state->sockfd, SOL_SOCKET, SO_REUSEADDR, &set, sizeof(set));
- if (setsockopt(state->sockfd, SOL_SOCKET, SO_BROADCAST, &set, sizeof(set)) == -1) {
- dbg("MODE APP : brodcast failed.\n");
- close(state->sockfd);
- return -1;
- }
- xstrncpy(ifr.ifr_name, state->iface, IFNAMSIZ);
- ifr.ifr_name[IFNAMSIZ -1] = '\0';
- setsockopt(state->sockfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));
- memset(&addr, 0, sizeof(addr));
- addr.sin_family = AF_INET;
- addr.sin_port = htons(DHCPC_CLIENT_PORT);
- addr.sin_addr.s_addr = INADDR_ANY ;
- if (bind(state->sockfd, (struct sockaddr *) &addr, sizeof(addr))) {
- close(state->sockfd);
- dbg("MODE APP : bind failed.\n");
- return -1;
- }
- state->mode = MODE_APP;
- dbg("MODE APP : success\n");
- return 0;
- }
- static int read_raw(void)
- {
- dhcp_raw_t packet;
- int bytes = 0;
- memset(&packet, 0, sizeof(packet));
- if ((bytes = read(state->sockfd, &packet, sizeof(packet))) < 0) {
- dbg("\tPacket read error, ignoring\n");
- return bytes;
- }
- if (bytes < (int) (sizeof(packet.iph) + sizeof(packet.udph))) {
- dbg("\tPacket is too short, ignoring\n");
- return -2;
- }
- if (bytes < ntohs(packet.iph.tot_len)) {
- dbg("\tOversized packet, ignoring\n");
- return -2;
- }
- // ignore any extra garbage bytes
- bytes = ntohs(packet.iph.tot_len);
- // make sure its the right packet for us, and that it passes sanity checks
- if (packet.iph.protocol != IPPROTO_UDP || packet.iph.version != IPVERSION
- || packet.iph.ihl != (sizeof(packet.iph) >> 2)
- || packet.udph.dest != htons(DHCPC_CLIENT_PORT)
- || ntohs(packet.udph.len) != (uint16_t)(bytes - sizeof(packet.iph))) {
- dbg("\tUnrelated/bogus packet, ignoring\n");
- return -2;
- }
- // Verify IP checksum.
- if (dhcp_checksum(&packet.iph, sizeof(packet.iph)) != 0) {
- dbg("\tBad IP header checksum, ignoring\n");
- return -2;
- }
- // Verify UDP checksum. From RFC 768, the UDP checksum is done over the IPv4
- // pseudo header, the UDP header and the UDP data. The IPv4 pseudo header
- // includes saddr, daddr, protocol, and UDP length. The IP header has to be
- // modified for this.
- memset(&packet.iph, 0, ((size_t) &((struct iphdr *)0)->protocol));
- packet.iph.check = 0;
- packet.iph.tot_len = packet.udph.len;
- if (packet.udph.check != 0 && dhcp_checksum(&packet, bytes) != 0) {
- dbg("\tPacket with bad UDP checksum received, ignoring\n");
- return -2;
- }
- memcpy(&state->pdhcp, &packet.dhcp, bytes - (sizeof(packet.iph) + sizeof(packet.udph)));
- if (state->pdhcp.cookie != htonl(DHCP_MAGIC)) {
- dbg("\tPacket with bad magic, ignoring\n");
- return -2;
- }
- return bytes - sizeof(packet.iph) - sizeof(packet.udph);
- }
- static int read_app(void)
- {
- int ret;
- memset(&state->pdhcp, 0, sizeof(dhcp_msg_t));
- if ((ret = read(state->sockfd, &state->pdhcp, sizeof(dhcp_msg_t))) < 0) {
- dbg("Packet read error, ignoring\n");
- return ret; /* returns -1 */
- }
- if (state->pdhcp.cookie != htonl(DHCP_MAGIC)) {
- dbg("Packet with bad magic, ignoring\n");
- return -2;
- }
- return ret;
- }
- // Sends data through raw socket.
- static int send_raw(void)
- {
- struct sockaddr_ll dest_sll;
- dhcp_raw_t packet;
- unsigned padding;
- int fd, result = -1;
- memset(&packet, 0, sizeof(dhcp_raw_t));
- memcpy(&packet.dhcp, &state->pdhcp, sizeof(dhcp_msg_t));
- if ((fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP))) < 0) {
- dbg("SEND RAW: socket failed\n");
- return result;
- }
- memset(&dest_sll, 0, sizeof(dest_sll));
- dest_sll.sll_family = AF_PACKET;
- dest_sll.sll_protocol = htons(ETH_P_IP);
- dest_sll.sll_ifindex = state->ifindex;
- dest_sll.sll_halen = 6;
- memcpy(dest_sll.sll_addr, bmacaddr , 6);
- if (bind(fd, (struct sockaddr *) &dest_sll, sizeof(dest_sll)) < 0) {
- dbg("SEND RAW: bind failed\n");
- close(fd);
- return result;
- }
- padding = 308 - 1 - dhcp_opt_size(state->pdhcp.options);
- packet.iph.protocol = IPPROTO_UDP;
- packet.iph.saddr = INADDR_ANY;
- packet.iph.daddr = INADDR_BROADCAST;
- packet.udph.source = htons(DHCPC_CLIENT_PORT);
- packet.udph.dest = htons(DHCPC_SERVER_PORT);
- packet.udph.len = htons(sizeof(dhcp_raw_t) - sizeof(struct iphdr) - padding);
- packet.iph.tot_len = packet.udph.len;
- packet.udph.check = dhcp_checksum(&packet, sizeof(dhcp_raw_t) - padding);
- packet.iph.tot_len = htons(sizeof(dhcp_raw_t) - padding);
- packet.iph.ihl = sizeof(packet.iph) >> 2;
- packet.iph.version = IPVERSION;
- packet.iph.ttl = IPDEFTTL;
- packet.iph.check = dhcp_checksum(&packet.iph, sizeof(packet.iph));
- result = sendto(fd, &packet, sizeof(dhcp_raw_t) - padding, 0,
- (struct sockaddr *) &dest_sll, sizeof(dest_sll));
- close(fd);
- if (result < 0) dbg("SEND RAW: PACKET send error\n");
- return result;
- }
- // Sends data through UDP socket.
- static int send_app(void)
- {
- struct sockaddr_in cli;
- int fd, ret = -1;
- if ((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
- dbg("SEND APP: sock failed.\n");
- return ret;
- }
- setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &set, sizeof(set));
- memset(&cli, 0, sizeof(cli));
- cli.sin_family = AF_INET;
- cli.sin_port = htons(DHCPC_CLIENT_PORT);
- cli.sin_addr.s_addr = state->pdhcp.ciaddr;
- if (bind(fd, (struct sockaddr *)&cli, sizeof(cli)) == -1) {
- dbg("SEND APP: bind failed.\n");
- goto error_fd;
- }
- memset(&cli, 0, sizeof(cli));
- cli.sin_family = AF_INET;
- cli.sin_port = htons(DHCPC_SERVER_PORT);
- cli.sin_addr.s_addr = state->serverid.s_addr;
- if (connect(fd, (struct sockaddr *)&cli, sizeof(cli)) == -1) {
- dbg("SEND APP: connect failed.\n");
- goto error_fd;
- }
- int padding = 308 - 1 - dhcp_opt_size(state->pdhcp.options);
- if((ret = write(fd, &state->pdhcp, sizeof(dhcp_msg_t) - padding)) < 0) {
- dbg("SEND APP: write failed error %d\n", ret);
- goto error_fd;
- }
- dbg("SEND APP: write success wrote %d\n", ret);
- error_fd:
- close(fd);
- return ret;
- }
- // Generic signal handler real handling is done in main funcrion.
- static void signal_handler(int sig)
- {
- unsigned char ch = sig;
- if (write(sigfd.wr, &ch, 1) != 1) dbg("can't send signal\n");
- }
- // signal setup for SIGUSR1 SIGUSR2 SIGTERM
- static int setup_signal()
- {
- if (pipe((int *)&sigfd) < 0) {
- dbg("signal pipe failed\n");
- return -1;
- }
- fcntl(sigfd.wr , F_SETFD, FD_CLOEXEC);
- fcntl(sigfd.rd , F_SETFD, FD_CLOEXEC);
- int flags = fcntl(sigfd.wr, F_GETFL);
- fcntl(sigfd.wr, F_SETFL, flags | O_NONBLOCK);
- signal(SIGUSR1, signal_handler);
- signal(SIGUSR2, signal_handler);
- signal(SIGTERM, signal_handler);
- return 0;
- }
- // adds client id to dhcp packet
- static uint8_t *dhcpc_addclientid(uint8_t *optptr)
- {
- *optptr++ = DHCP_OPTION_CLIENTID;
- *optptr++ = 7;
- *optptr++ = 1;
- memcpy(optptr, &state->macaddr, 6);
- return optptr + 6;
- }
- // adds messege type to dhcp packet
- static uint8_t *dhcpc_addmsgtype(uint8_t *optptr, uint8_t type)
- {
- *optptr++ = DHCP_OPTION_MSG_TYPE;
- *optptr++ = 1;
- *optptr++ = type;
- return optptr;
- }
- // adds max size to dhcp packet
- static uint8_t *dhcpc_addmaxsize(uint8_t *optptr, uint16_t size)
- {
- *optptr++ = DHCP_OPTION_MAX_SIZE;
- *optptr++ = 2;
- memcpy(optptr, &size, 2);
- return optptr + 2;
- }
- static uint8_t *dhcpc_addstropt(uint8_t *optptr, uint8_t opcode, char* str, int len)
- {
- *optptr++ = opcode;
- *optptr++ = len;
- memcpy(optptr, str, len);
- return optptr + len;
- }
- // adds server id to dhcp packet.
- static uint8_t *dhcpc_addserverid(struct in_addr *serverid, uint8_t *optptr)
- {
- *optptr++ = DHCP_OPTION_SERVER_ID;
- *optptr++ = 4;
- memcpy(optptr, &serverid->s_addr, 4);
- return optptr + 4;
- }
- // adds requested ip address to dhcp packet.
- static uint8_t *dhcpc_addreqipaddr(struct in_addr *ipaddr, uint8_t *optptr)
- {
- *optptr++ = DHCP_OPTION_REQ_IPADDR;
- *optptr++ = 4;
- memcpy(optptr, &ipaddr->s_addr, 4);
- return optptr + 4;
- }
- // adds hostname to dhcp packet.
- static uint8_t *dhcpc_addfdnname(uint8_t *optptr, char *hname)
- {
- int size = strlen(hname);
- *optptr++ = DHCP_OPTION_FQDN;
- *optptr++ = size + 3;
- *optptr++ = 0x1; //flags
- optptr += 2; // two blank bytes
- strcpy((char*)optptr, hname); // name
- return optptr + size;
- }
- // adds request options using -o,-O flag to dhcp packet
- static uint8_t *dhcpc_addreqoptions(uint8_t *optptr)
- {
- uint8_t *len;
- *optptr++ = DHCP_OPTION_REQ_LIST;
- len = optptr;
- *len = 0;
- optptr++;
- if (!(toys.optflags & FLAG_o)) {
- *len = 4;
- *optptr++ = DHCP_OPTION_SUBNET_MASK;
- *optptr++ = DHCP_OPTION_ROUTER;
- *optptr++ = DHCP_OPTION_DNS_SERVER;
- *optptr++ = DHCP_OPTION_BROADCAST;
- }
- if (toys.optflags & FLAG_O) {
- memcpy(optptr++, raw_opt, raw_optcount);
- *len += raw_optcount;
- }
- return optptr;
- }
- static uint8_t *dhcpc_addend(uint8_t *optptr)
- {
- *optptr++ = DHCP_OPTION_END;
- return optptr;
- }
- // Sets values of -x options in dhcp discover and request packet.
- static uint8_t* set_xopt(uint8_t *optptr)
- {
- int count;
- int size = ARRAY_LEN(options_list);
- for (count = 0; count < size; count++) {
- if ((options_list[count].len == 0) || (options_list[count].val == NULL)) continue;
- *optptr++ = (uint8_t) (options_list[count].code & 0x00FF);
- *optptr++ = (uint8_t) options_list[count].len;
- memcpy(optptr, options_list[count].val, options_list[count].len);
- optptr += options_list[count].len;
- }
- return optptr;
- }
- static uint32_t get_option_serverid (uint8_t *opt, dhcpc_result_t *presult)
- {
- uint32_t var = 0;
- while (*opt != DHCP_OPTION_SERVER_ID) {
- if (*opt == DHCP_OPTION_END) return var;
- opt += opt[1] + 2;
- }
- memcpy(&var, opt+2, sizeof(uint32_t));
- state->serverid.s_addr = var;
- presult->serverid.s_addr = state->serverid.s_addr;
- presult->serverid.s_addr = ntohl(presult->serverid.s_addr);
- return var;
- }
- static uint8_t get_option_msgtype(uint8_t *opt)
- {
- uint32_t var = 0;
- while (*opt != DHCP_OPTION_MSG_TYPE) {
- if (*opt == DHCP_OPTION_END) return var;
- opt += opt[1] + 2;
- }
- memcpy(&var, opt+2, sizeof(uint8_t));
- return var;
- }
- static uint8_t get_option_lease(uint8_t *opt, dhcpc_result_t *presult)
- {
- uint32_t var = 0;
- while (*opt != DHCP_OPTION_LEASE_TIME) {
- if (*opt == DHCP_OPTION_END) return var;
- opt += opt[1] + 2;
- }
- memcpy(&var, opt+2, sizeof(uint32_t));
- var = htonl(var);
- presult->lease_time = var;
- return var;
- }
- // sends dhcp msg of MSGTYPE
- static int dhcpc_sendmsg(int msgtype)
- {
- uint8_t *pend;
- struct in_addr rqsd;
- char *vendor;
- // Create the common message header settings
- memset(&state->pdhcp, 0, sizeof(dhcp_msg_t));
- state->pdhcp.op = DHCP_REQUEST;
- state->pdhcp.htype = DHCP_HTYPE_ETHERNET;
- state->pdhcp.hlen = 6;
- state->pdhcp.xid = xid;
- memcpy(state->pdhcp.chaddr, state->macaddr, 6);
- memset(&state->pdhcp.chaddr[6], 0, 10);
- state->pdhcp.cookie = htonl(DHCP_MAGIC);;
- // Add the common header options
- pend = state->pdhcp.options;
- pend = dhcpc_addmsgtype(pend, msgtype);
- if (!(toys.optflags & FLAG_C)) pend = dhcpc_addclientid(pend);
- // Handle the message specific settings
- switch (msgtype) {
- case DHCPDISCOVER: // Broadcast DISCOVER message to all servers
- state->pdhcp.flags = htons(BOOTP_BROADCAST); // Broadcast bit.
- if (toys.optflags & FLAG_r) {
- inet_aton(TT.req_ip, &rqsd);
- pend = dhcpc_addreqipaddr(&rqsd, pend);
- }
- pend = dhcpc_addmaxsize(pend, htons(sizeof(dhcp_raw_t)));
- vendor = (toys.optflags & FLAG_V) ? TT.vendor_cls : "toybox\0";
- pend = dhcpc_addstropt(pend, DHCP_OPTION_VENDOR, vendor, strlen(vendor));
- if (toys.optflags & FLAG_H) pend = dhcpc_addstropt(pend, DHCP_OPTION_HOST_NAME, TT.hostname, strlen(TT.hostname));
- if (toys.optflags & FLAG_F) pend = dhcpc_addfdnname(pend, TT.fdn_name);
- if (!(toys.optflags & FLAG_o) || (toys.optflags & FLAG_O))
- pend = dhcpc_addreqoptions(pend);
- if (toys.optflags & FLAG_x) pend = set_xopt(pend);
- break;
- case DHCPREQUEST: // Send REQUEST message to the server that sent the *first* OFFER
- state->pdhcp.flags = htons(BOOTP_BROADCAST); // Broadcast bit.
- if (state->status == STATE_RENEWING) memcpy(&state->pdhcp.ciaddr, &state->ipaddr.s_addr, 4);
- pend = dhcpc_addmaxsize(pend, htons(sizeof(dhcp_raw_t)));
- rqsd.s_addr = htonl(server);
- pend = dhcpc_addserverid(&rqsd, pend);
- pend = dhcpc_addreqipaddr(&state->ipaddr, pend);
- vendor = (toys.optflags & FLAG_V) ? TT.vendor_cls : "toybox\0";
- pend = dhcpc_addstropt(pend, DHCP_OPTION_VENDOR, vendor, strlen(vendor));
- if (toys.optflags & FLAG_H) pend = dhcpc_addstropt(pend, DHCP_OPTION_HOST_NAME, TT.hostname, strlen(TT.hostname));
- if (toys.optflags & FLAG_F) pend = dhcpc_addfdnname(pend, TT.fdn_name);
- if (!(toys.optflags & FLAG_o) || (toys.optflags & FLAG_O))
- pend = dhcpc_addreqoptions(pend);
- if (toys.optflags & FLAG_x) pend = set_xopt(pend);
- break;
- case DHCPRELEASE: // Send RELEASE message to the server.
- memcpy(&state->pdhcp.ciaddr, &state->ipaddr.s_addr, 4);
- rqsd.s_addr = htonl(server);
- pend = dhcpc_addserverid(&rqsd, pend);
- break;
- default:
- return -1;
- }
- pend = dhcpc_addend(pend);
- if (state->mode == MODE_APP) return send_app();
- return send_raw();
- }
- /*
- * parses options from received dhcp packet at OPTPTR and
- * stores result in PRESULT or MSGOPT_LIST
- */
- static uint8_t dhcpc_parseoptions(dhcpc_result_t *presult, uint8_t *optptr)
- {
- uint8_t type = 0, *options, overloaded = 0;;
- uint16_t flag = 0;
- uint32_t convtmp = 0;
- char *dest, *pfx;
- struct in_addr addr;
- int count, optlen, size = ARRAY_LEN(options_list);
- if (toys.optflags & FLAG_x) {
- if(msgopt_list){
- for (count = 0; count < size; count++){
- if(msgopt_list[count].val) free(msgopt_list[count].val);
- msgopt_list[count].val = NULL;
- msgopt_list[count].len = 0;
- }
- } else {
- msgopt_list = xmalloc(sizeof(options_list));
- memcpy(msgopt_list, options_list, sizeof(options_list));
- for (count = 0; count < size; count++) {
- msgopt_list[count].len = 0;
- msgopt_list[count].val = NULL;
- }
- }
- } else {
- msgopt_list = options_list;
- for (count = 0; count < size; count++) {
- msgopt_list[count].len = 0;
- if(msgopt_list[count].val) free(msgopt_list[count].val);
- msgopt_list[count].val = NULL;
- }
- }
- while (*optptr != DHCP_OPTION_END) {
- if (*optptr == DHCP_OPTION_PADDING) {
- optptr++;
- continue;
- }
- if (*optptr == DHCP_OPTION_OVERLOAD) {
- overloaded = optptr[2];
- optptr += optptr[1] + 2;
- continue;
- }
- for (count = 0, flag = 0; count < size; count++) {
- if ((msgopt_list[count].code & 0X00FF) == *optptr) {
- flag = (msgopt_list[count].code & 0XFF00);
- break;
- }
- }
- switch (flag) {
- case DHCP_NUM32:
- memcpy(&convtmp, &optptr[2], sizeof(uint32_t));
- convtmp = htonl(convtmp);
- sprintf(toybuf, "%u", convtmp);
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_NUM16:
- memcpy(&convtmp, &optptr[2], sizeof(uint16_t));
- convtmp = htons(convtmp);
- sprintf(toybuf, "%u", convtmp);
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_NUM8:
- memcpy(&convtmp, &optptr[2], sizeof(uint8_t));
- sprintf(toybuf, "%u", convtmp);
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_IP:
- memcpy(&convtmp, &optptr[2], sizeof(uint32_t));
- addr.s_addr = convtmp;
- sprintf(toybuf, "%s", inet_ntoa(addr));
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_STRING:
- sprintf(toybuf, "%.*s", optptr[1], &optptr[2]);
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_IPLIST:
- options = &optptr[2];
- optlen = optptr[1];
- dest = toybuf;
- while (optlen) {
- memcpy(&convtmp, options, sizeof(uint32_t));
- addr.s_addr = convtmp;
- dest += sprintf(dest, "%s ", inet_ntoa(addr));
- options += 4;
- optlen -= 4;
- }
- *(dest - 1) = '\0';
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- case DHCP_STRLST: //FIXME: do smthing.
- case DHCP_IPPLST:
- break;
- case DHCP_STCRTS:
- pfx = "";
- dest = toybuf;
- options = &optptr[2];
- optlen = optptr[1];
- while (optlen >= 1 + 4) {
- uint32_t nip = 0;
- int bytes;
- uint8_t *p_tmp;
- unsigned mask = *options;
- if (mask > 32) break;
- optlen--;
- p_tmp = (void*) &nip;
- bytes = (mask + 7) / 8;
- while (--bytes >= 0) {
- *p_tmp++ = *options++;
- optlen--;
- }
- if (optlen < 4) break;
- dest += sprintf(dest, "%s%u.%u.%u.%u", pfx, ((uint8_t*) &nip)[0],
- ((uint8_t*) &nip)[1], ((uint8_t*) &nip)[2], ((uint8_t*) &nip)[3]);
- pfx = " ";
- dest += sprintf(dest, "/%u ", mask);
- dest += sprintf(dest, "%u.%u.%u.%u", options[0], options[1], options[2], options[3]);
- options += 4;
- optlen -= 4;
- }
- msgopt_list[count].val = strdup(toybuf);
- msgopt_list[count].len = strlen(toybuf);
- break;
- default: break;
- }
- optptr += optptr[1] + 2;
- }
- if ((overloaded == 1) || (overloaded == 3)) dhcpc_parseoptions(presult, optptr);
- if ((overloaded == 2) || (overloaded == 3)) dhcpc_parseoptions(presult, optptr);
- return type;
- }
- // parses recvd messege to check that it was for us.
- static uint8_t dhcpc_parsemsg(dhcpc_result_t *presult)
- {
- if (state->pdhcp.op == DHCP_REPLY
- && !memcmp(state->pdhcp.chaddr, state->macaddr, 6)
- && !memcmp(&state->pdhcp.xid, &xid, sizeof(xid))) {
- memcpy(&presult->ipaddr.s_addr, &state->pdhcp.yiaddr, 4);
- presult->ipaddr.s_addr = ntohl(presult->ipaddr.s_addr);
- return get_option_msgtype(state->pdhcp.options);
- }
- return 0;
- }
- // Sends a IP renew request.
- static void renew(void)
- {
- infomsg(infomode, "Performing a DHCP renew");
- switch (state->status) {
- case STATE_INIT:
- break;
- case STATE_BOUND:
- mode_raw();
- case STATE_RENEWING: // FALLTHROUGH
- case STATE_REBINDING: // FALLTHROUGH
- state->status = STATE_RENEW_REQUESTED;
- break;
- case STATE_RENEW_REQUESTED:
- run_script(NULL, "deconfig");
- case STATE_REQUESTING: // FALLTHROUGH
- case STATE_RELEASED: // FALLTHROUGH
- mode_raw();
- state->status = STATE_INIT;
- break;
- default: break;
- }
- }
- // Sends a IP release request.
- static void release(void)
- {
- char buffer[sizeof("255.255.255.255\0")];
- struct in_addr temp_addr;
- mode_app();
- // send release packet
- if (state->status == STATE_BOUND || state->status == STATE_RENEWING || state->status == STATE_REBINDING) {
- temp_addr.s_addr = htonl(server);
- xstrncpy(buffer, inet_ntoa(temp_addr), sizeof(buffer));
- temp_addr.s_addr = state->ipaddr.s_addr;
- infomsg( infomode, "Unicasting a release of %s to %s", inet_ntoa(temp_addr), buffer);
- dhcpc_sendmsg(DHCPRELEASE);
- run_script(NULL, "deconfig");
- }
- infomsg(infomode, "Entering released state");
- close(state->sockfd);
- state->sockfd = -1;
- state->mode = MODE_OFF;
- state->status = STATE_RELEASED;
- }
- static void free_option_stores(void)
- {
- int count, size = ARRAY_LEN(options_list);
- for (count = 0; count < size; count++)
- if (options_list[count].val) free(options_list[count].val);
- if (toys.optflags & FLAG_x) {
- for (count = 0; count < size; count++)
- if (msgopt_list[count].val) free(msgopt_list[count].val);
- free(msgopt_list);
- }
- }
- void dhcp_main(void)
- {
- struct timeval tv;
- int retval, bufflen = 0;
- dhcpc_result_t result;
- uint8_t packets = 0, retries = 0;
- uint32_t timeout = 0, waited = 0;
- fd_set rfds;
- xid = 0;
- setlinebuf(stdout);
- dbg = dummy;
- if (toys.optflags & FLAG_v) dbg = xprintf;
- if (toys.optflags & FLAG_p) write_pid(TT.pidfile);
- retries = TT.retries;
- if (toys.optflags & FLAG_S) {
- openlog("UDHCPC :", LOG_PID, LOG_DAEMON);
- infomode |= LOG_SYSTEM;
- }
- infomsg(infomode, "dhcp started");
- if (toys.optflags & FLAG_O) {
- while (TT.req_opt) {
- raw_opt[raw_optcount] = (uint8_t) strtoopt(TT.req_opt->arg, 1);
- raw_optcount++;
- TT.req_opt = TT.req_opt->next;
- }
- }
- if (toys.optflags & FLAG_x) {
- while (TT.pkt_opt) {
- (void) strtoopt(TT.pkt_opt->arg, 0);
- TT.pkt_opt = TT.pkt_opt->next;
- }
- }
- memset(&result, 0, sizeof(dhcpc_result_t));
- state = (dhcpc_state_t*) xmalloc(sizeof(dhcpc_state_t));
- memset(state, 0, sizeof(dhcpc_state_t));
- state->iface = (toys.optflags & FLAG_i) ? TT.iface : "eth0";
- if (get_interface(state->iface, &state->ifindex, NULL, state->macaddr))
- perror_exit("Failed to get interface %s", state->iface);
- run_script(NULL, "deconfig");
- setup_signal();
- state->status = STATE_INIT;
- mode_raw();
- fcntl(state->sockfd, F_SETFD, FD_CLOEXEC);
- for (;;) {
- FD_ZERO(&rfds);
- if (state->sockfd >= 0) FD_SET(state->sockfd, &rfds);
- FD_SET(sigfd.rd, &rfds);
- tv.tv_sec = timeout - waited;
- tv.tv_usec = 0;
- retval = 0;
- int maxfd = (sigfd.rd > state->sockfd)? sigfd.rd : state->sockfd;
- dbg("select wait ....\n");
- uint32_t timestmp = time(NULL);
- if((retval = select(maxfd + 1, &rfds, NULL, NULL, &tv)) < 0) {
- if (errno == EINTR) {
- waited += (unsigned) time(NULL) - timestmp;
- continue;
- }
- perror_exit("Error in select");
- }
- if (!retval) { // Timed out
- if (get_interface(state->iface, &state->ifindex, NULL, state->macaddr))
- error_exit("Interface lost %s\n", state->iface);
- switch (state->status) {
- case STATE_INIT:
- if (packets < retries) {
- if (!packets) xid = getxid();
- run_script(NULL, "deconfig");
- infomsg(infomode, "Sending discover...");
- dhcpc_sendmsg(DHCPDISCOVER);
- server = 0;
- timeout = TT.timeout;
- waited = 0;
- packets++;
- continue;
- }
- lease_fail:
- run_script(NULL,"leasefail");
- if (toys.optflags & FLAG_n) {
- infomsg(infomode, "Lease failed. Exiting");
- goto ret_with_sockfd;
- }
- if (toys.optflags & FLAG_b) {
- infomsg(infomode, "Lease failed. Going Daemon mode");
- daemon(0, 0);
- if (toys.optflags & FLAG_p) write_pid(TT.pidfile);
- toys.optflags &= ~FLAG_b;
- toys.optflags |= FLAG_f;
- }
- timeout = TT.tryagain;
- waited = 0;
- packets = 0;
- continue;
- case STATE_REQUESTING:
- if (packets < retries) {
- memcpy(&state->ipaddr.s_addr,&state->pdhcp.yiaddr, 4);
- dhcpc_sendmsg(DHCPREQUEST);
- infomsg(infomode, "Sending select for %d.%d.%d.%d...",
- (result.ipaddr.s_addr >> 24) & 0xff, (result.ipaddr.s_addr >> 16) & 0xff, (result.ipaddr.s_addr >> 8) & 0xff, (result.ipaddr.s_addr) & 0xff);
- timeout = TT.timeout;
- waited = 0;
- packets++;
- continue;
- }
- mode_raw();
- state->status = STATE_INIT;
- goto lease_fail;
- case STATE_BOUND:
- state->status = STATE_RENEWING;
- dbg("Entering renew state\n");
- // FALLTHROUGH
- case STATE_RENEW_REQUESTED: // FALLTHROUGH
- case STATE_RENEWING:
- renew_requested:
- if (timeout > 60) {
- dhcpc_sendmsg(DHCPREQUEST);
- timeout >>= 1;
- waited = 0;
- continue;
- }
- dbg("Entering rebinding state\n");
- state->status = STATE_REBINDING;
- // FALLTHROUGH
- case STATE_REBINDING:
- mode_raw();
- if (timeout > 0) {
- dhcpc_sendmsg(DHCPREQUEST);
- timeout >>= 1;
- waited = 0;
- continue;
- }
- infomsg(infomode, "Lease lost, entering INIT state");
- run_script(NULL, "deconfig");
- state->status = STATE_INIT;
- timeout = 0;
- waited = 0;
- packets = 0;
- continue;
- default: break;
- }
- timeout = INT_MAX;
- waited = 0;
- continue;
- }
- if (FD_ISSET(sigfd.rd, &rfds)) { // Some Activity on RDFDs : is signal
- unsigned char sig;
- if (read(sigfd.rd, &sig, 1) != 1) {
- dbg("signal read failed.\n");
- continue;
- }
- switch (sig) {
- case SIGUSR1:
- infomsg(infomode, "Received SIGUSR1");
- renew();
- packets = 0;
- waited = 0;
- if (state->status == STATE_RENEW_REQUESTED) goto renew_requested;
- if (state->status == STATE_INIT) timeout = 0;
- continue;
- case SIGUSR2:
- infomsg(infomode, "Received SIGUSR2");
- release();
- timeout = INT_MAX;
- waited = 0;
- packets = 0;
- continue;
- case SIGTERM:
- infomsg(infomode, "Received SIGTERM");
- if (toys.optflags & FLAG_R) release();
- goto ret_with_sockfd;
- default: break;
- }
- }
- if (FD_ISSET(state->sockfd, &rfds)) { // Some Activity on RDFDs : is socket
- dbg("main sock read\n");
- uint8_t msgType;
- if (state->mode == MODE_RAW) bufflen = read_raw();
- if (state->mode == MODE_APP) bufflen = read_app();
- if (bufflen < 0) {
- if (state->mode == MODE_RAW) mode_raw();
- if (state->mode == MODE_APP) mode_app();
- continue;
- }
- waited += time(NULL) - timestmp;
- memset(&result, 0, sizeof(dhcpc_result_t));
- msgType = dhcpc_parsemsg(&result);
- if (msgType != DHCPNAK && result.ipaddr.s_addr == 0 ) continue; // no ip for me ignore
- if (!msgType || !get_option_serverid(state->pdhcp.options, &result)) continue; //no server id ignore
- if (msgType == DHCPOFFER && server == 0) server = result.serverid.s_addr; // select the server
- if (result.serverid.s_addr != server) continue; // not from the server we requested ignore
- dhcpc_parseoptions(&result, state->pdhcp.options);
- get_option_lease(state->pdhcp.options, &result);
- switch (state->status) {
- case STATE_INIT:
- if (msgType == DHCPOFFER) {
- state->status = STATE_REQUESTING;
- mode_raw();
- timeout = 0;
- waited = 0;
- packets = 0;
- }
- continue;
- case STATE_REQUESTING: // FALLTHROUGH
- case STATE_RENEWING: // FALLTHROUGH
- case STATE_RENEW_REQUESTED: // FALLTHROUGH
- case STATE_REBINDING:
- if (msgType == DHCPACK) {
- timeout = result.lease_time / 2;
- run_script(&result, state->status == STATE_REQUESTING ? "bound" : "renew");
- state->status = STATE_BOUND;
- infomsg(infomode, "Lease of %d.%d.%d.%d obtained, lease time %d from server %d.%d.%d.%d",
- (result.ipaddr.s_addr >> 24) & 0xff, (result.ipaddr.s_addr >> 16) & 0xff, (result.ipaddr.s_addr >> 8) & 0xff, (result.ipaddr.s_addr) & 0xff,
- result.lease_time,
- (result.serverid.s_addr >> 24) & 0xff, (result.serverid.s_addr >> 16) & 0xff, (result.serverid.s_addr >> 8) & 0xff, (result.serverid.s_addr) & 0xff);
- if (toys.optflags & FLAG_q) {
- if (toys.optflags & FLAG_R) release();
- goto ret_with_sockfd;
- }
- toys.optflags &= ~FLAG_n;
- if (!(toys.optflags & FLAG_f)) {
- daemon(0, 0);
- toys.optflags |= FLAG_f;
- if (toys.optflags & FLAG_p) write_pid(TT.pidfile);
- }
- waited = 0;
- continue;
- } else if (msgType == DHCPNAK) {
- dbg("NACK received.\n");
- run_script(&result, "nak");
- if (state->status != STATE_REQUESTING) run_script(NULL, "deconfig");
- mode_raw();
- sleep(3);
- state->status = STATE_INIT;
- state->ipaddr.s_addr = 0;
- server = 0;
- timeout = 0;
- packets = 0;
- waited = 0;
- }
- continue;
- default: break;
- }
- }
- }
- ret_with_sockfd:
- if (CFG_TOYBOX_FREE) {
- free_option_stores();
- if (state->sockfd > 0) close(state->sockfd);
- free(state);
- }
- }
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