diff options
Diffstat (limited to 'mdk-stage1/dhcp.c')
-rw-r--r-- | mdk-stage1/dhcp.c | 679 |
1 files changed, 0 insertions, 679 deletions
diff --git a/mdk-stage1/dhcp.c b/mdk-stage1/dhcp.c deleted file mode 100644 index 32c7a932b..000000000 --- a/mdk-stage1/dhcp.c +++ /dev/null @@ -1,679 +0,0 @@ -/* - * Guillaume Cottenceau (gc@mandrakesoft.com) - * - * Copyright 2000 MandrakeSoft - * - * This software may be freely redistributed under the terms of the GNU - * public license. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - */ - -/* - * Portions from Erik Troan (ewt@redhat.com) - * - * Copyright 1996 Red Hat Software - * - */ - -/* - * Portions from GRUB -- GRand Unified Bootloader - * Copyright (C) 2000 Free Software Foundation, Inc. - */ - - -#include <stdlib.h> -#include <unistd.h> -#include <stdio.h> -#include <string.h> -#include <sys/socket.h> -#include <sys/ioctl.h> -#include <net/if.h> -#include <arpa/inet.h> -#include <net/route.h> -#include <errno.h> -#include <net/ethernet.h> -#include <netinet/ip.h> -#include <netinet/udp.h> -#include <sys/time.h> -#include <time.h> -#include <fcntl.h> -#include <sys/poll.h> - -#include "stage1.h" -#include "log.h" -#include "network.h" -#include "frontend.h" -#include "automatic.h" - -#include "dhcp.h" - - -typedef int bp_int32; -typedef short bp_int16; - -#define BOOTP_OPTION_NETMASK 1 -#define BOOTP_OPTION_GATEWAY 3 -#define BOOTP_OPTION_DNS 6 -#define BOOTP_OPTION_HOSTNAME 12 -#define BOOTP_OPTION_DOMAIN 15 -#define BOOTP_OPTION_BROADCAST 28 - -#define DHCP_OPTION_REQADDR 50 -#define DHCP_OPTION_LEASE 51 -#define DHCP_OPTION_TYPE 53 -#define DHCP_OPTION_SERVER 54 -#define DHCP_OPTION_OPTIONREQ 55 -#define DHCP_OPTION_MAXSIZE 57 - -#define DHCP_OPTION_CLIENT_IDENTIFIER 61 - -#define BOOTP_CLIENT_PORT 68 -#define BOOTP_SERVER_PORT 67 - -#define BOOTP_OPCODE_REQUEST 1 -#define BOOTP_OPCODE_REPLY 2 - -#define DHCP_TYPE_DISCOVER 1 -#define DHCP_TYPE_OFFER 2 -#define DHCP_TYPE_REQUEST 3 -#define DHCP_TYPE_ACK 5 -#define DHCP_TYPE_RELEASE 7 - -#define BOOTP_VENDOR_LENGTH 64 -#define DHCP_VENDOR_LENGTH 340 - -struct bootp_request { - char opcode; - char hw; - char hwlength; - char hopcount; - bp_int32 id; - bp_int16 secs; - bp_int16 flags; - bp_int32 ciaddr, yiaddr, server_ip, bootp_gw_ip; - char hwaddr[16]; - char servername[64]; - char bootfile[128]; - char vendor[DHCP_VENDOR_LENGTH]; -} ; - -static const char vendor_cookie[] = { 99, 130, 83, 99, 255 }; - - -static unsigned int verify_checksum(void * buf2, int length2) -{ - unsigned int csum = 0; - unsigned short * sp; - - for (sp = (unsigned short *) buf2; length2 > 0; (length2 -= 2), sp++) - csum += *sp; - - while (csum >> 16) - csum = (csum & 0xffff) + (csum >> 16); - - return (csum == 0xffff); -} - - -static int initial_setup_interface(char * device, int s) { - struct sockaddr_in * addrp; - struct ifreq req; - struct rtentry route; - int true = 1; - - addrp = (struct sockaddr_in *) &req.ifr_addr; - - strcpy(req.ifr_name, device); - addrp->sin_family = AF_INET; - addrp->sin_port = 0; - memset(&addrp->sin_addr, 0, sizeof(addrp->sin_addr)); - - req.ifr_flags = 0; /* take it down */ - if (ioctl(s, SIOCSIFFLAGS, &req)) { - log_perror("SIOCSIFFLAGS (downing)"); - return -1; - } - - addrp->sin_family = AF_INET; - addrp->sin_addr.s_addr = htonl(0); - if (ioctl(s, SIOCSIFADDR, &req)) { - log_perror("SIOCSIFADDR"); - return -1; - } - - req.ifr_flags = IFF_UP | IFF_BROADCAST | IFF_RUNNING; - if (ioctl(s, SIOCSIFFLAGS, &req)) { - log_perror("SIOCSIFFLAGS (upping)"); - return -1; - } - - memset(&route, 0, sizeof(route)); - memcpy(&route.rt_gateway, addrp, sizeof(*addrp)); - - addrp->sin_family = AF_INET; - addrp->sin_port = 0; - addrp->sin_addr.s_addr = INADDR_ANY; - memcpy(&route.rt_dst, addrp, sizeof(*addrp)); - memcpy(&route.rt_genmask, addrp, sizeof(*addrp)); - - route.rt_dev = device; - route.rt_flags = RTF_UP; - route.rt_metric = 0; - - if (ioctl(s, SIOCADDRT, &route)) { - if (errno != EEXIST) { - close(s); - log_perror("SIOCADDRT"); - return -1; - } - } - - if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &true, sizeof(true))) { - close(s); - log_perror("setsockopt"); - return -1; - } - - /* I need to sleep a bit in order for kernel to finish init of the - network device; this would allow to not send further multiple - dhcp requests when only one is needed. */ - wait_message("Bringing up networking..."); - sleep(2); - remove_wait_message(); - - return 0; -} - - -void set_missing_ip_info(struct interface_info * intf) -{ - bp_int32 ipNum = *((bp_int32 *) &intf->ip); - bp_int32 nmNum; - - if (intf->netmask.s_addr == 0) - inet_aton(guess_netmask(inet_ntoa(intf->ip)), &intf->netmask); - - nmNum = *((bp_int32 *) &intf->netmask); - - if (intf->broadcast.s_addr == 0) - *((bp_int32 *) &intf->broadcast) = (ipNum & nmNum) | ~(nmNum); - - if (intf->network.s_addr == 0) - *((bp_int32 *) &intf->network) = ipNum & nmNum; -} - -static void parse_reply(struct bootp_request * breq, struct interface_info * intf) -{ - unsigned char * chptr; - unsigned char option, length; - - if (breq->bootfile && strlen(breq->bootfile) > 0) - stage2_kickstart = strdup(breq->bootfile); - - memcpy(&intf->ip, &breq->yiaddr, 4); - - chptr = breq->vendor; - chptr += 4; - while (*chptr != 0xFF && (void *) chptr < (void *) breq->vendor + DHCP_VENDOR_LENGTH) { - char tmp_str[500]; - option = *chptr++; - if (!option) - continue; - length = *chptr++; - - switch (option) { - case BOOTP_OPTION_DNS: - memcpy(&dns_server, chptr, sizeof(dns_server)); - log_message("got dns %s", inet_ntoa(dns_server)); - if (length >= sizeof(dns_server)*2) { - memcpy(&dns_server2, chptr+sizeof(dns_server), sizeof(dns_server2)); - log_message("got dns2 %s", inet_ntoa(dns_server2)); - } - break; - - case BOOTP_OPTION_NETMASK: - memcpy(&intf->netmask, chptr, sizeof(intf->netmask)); - log_message("got netmask %s", inet_ntoa(intf->netmask)); - break; - - case BOOTP_OPTION_DOMAIN: - memcpy(tmp_str, chptr, length); - tmp_str[length] = '\0'; - domain = strdup(tmp_str); - log_message("got domain %s", domain); - break; - - case BOOTP_OPTION_BROADCAST: - memcpy(&intf->broadcast, chptr, sizeof(intf->broadcast)); - log_message("got broadcast %s", inet_ntoa(intf->broadcast)); - break; - - case BOOTP_OPTION_GATEWAY: - memcpy(&gateway, chptr, sizeof(gateway)); - log_message("got gateway %s", inet_ntoa(gateway)); - break; - - case BOOTP_OPTION_HOSTNAME: - memcpy(tmp_str, chptr, length); - tmp_str[length] = '\0'; - hostname = strdup(tmp_str); - log_message("got hostname %s", hostname); - break; - - } - - chptr += length; - } - - set_missing_ip_info(intf); -} - - -static void init_vendor_codes(struct bootp_request * breq) { - memcpy(breq->vendor, vendor_cookie, sizeof(vendor_cookie)); -} - -static char gen_hwaddr[16]; - -static int prepare_request(struct bootp_request * breq, int sock, char * device) -{ - struct ifreq req; - - memset(breq, 0, sizeof(*breq)); - - breq->opcode = BOOTP_OPCODE_REQUEST; - - strcpy(req.ifr_name, device); - if (ioctl(sock, SIOCGIFHWADDR, &req)) { - log_perror("SIOCSIFHWADDR"); - return -1; - } - - breq->hw = 1; /* ethernet */ - breq->hwlength = IFHWADDRLEN; - memcpy(breq->hwaddr, req.ifr_hwaddr.sa_data, IFHWADDRLEN); - memcpy(gen_hwaddr, req.ifr_hwaddr.sa_data, IFHWADDRLEN); - - breq->hopcount = 0; - - init_vendor_codes(breq); - - return 0; -} - -static int get_vendor_code(struct bootp_request * bresp, unsigned char option, void * data) -{ - unsigned char * chptr; - unsigned int length, theOption; - - chptr = bresp->vendor + 4; - while (*chptr != 0xFF && *chptr != option) { - theOption = *chptr++; - if (!theOption) - continue; - length = *chptr++; - chptr += length; - } - - if (*chptr++ == 0xff) - return 1; - - length = *chptr++; - memcpy(data, chptr, length); - - return 0; -} - - -static unsigned long currticks(void) -{ - struct timeval tv; - unsigned long csecs; - unsigned long ticks_per_csec, ticks_per_usec; - - /* Note: 18.2 ticks/sec. */ - - gettimeofday (&tv, 0); - csecs = tv.tv_sec / 10; - ticks_per_csec = csecs * 182; - ticks_per_usec = (((tv.tv_sec - csecs * 10) * 1000000 + tv.tv_usec) * 182 / 10000000); - return ticks_per_csec + ticks_per_usec; -} - - -#define BACKOFF_LIMIT 7 -#define TICKS_PER_SEC 18 -#define MAX_ARP_RETRIES 4 - -static void rfc951_sleep(int exp) -{ - static long seed = 0; - long q; - unsigned long tmo; - - if (exp > BACKOFF_LIMIT) - exp = BACKOFF_LIMIT; - - if (!seed) - /* Initialize linear congruential generator. */ - seed = (currticks () + *(long *) &gen_hwaddr + ((short *) gen_hwaddr)[2]); - - /* Simplified version of the LCG given in Bruce Scheier's - "Applied Cryptography". */ - q = seed / 53668; - if ((seed = 40014 * (seed - 53668 * q) - 12211 * q) < 0) - seed += 2147483563l; - - /* Compute mask. */ - for (tmo = 63; tmo <= 60 * TICKS_PER_SEC && --exp > 0; tmo = 2 * tmo + 1) - ; - - /* Sleep. */ - log_message("<sleep>"); - - for (tmo = (tmo & seed) + currticks (); currticks () < tmo;); -} - - -static int handle_transaction(int s, struct bootp_request * breq, struct bootp_request * bresp, - struct sockaddr_in * server_addr, int dhcp_type) -{ - struct pollfd polls; - int i, j; - int retry = 1; - int sin; - char eth_packet[ETH_FRAME_LEN]; - struct iphdr * ip_hdr; - struct udphdr * udp_hdr; - unsigned char type; - unsigned long starttime; - int timeout = 1; - - breq->id = starttime = currticks(); - breq->secs = 0; - - sin = socket(AF_PACKET, SOCK_DGRAM, ntohs(ETH_P_IP)); - if (sin < 0) { - log_perror("af_packet socket"); - return -1; - } - - while (retry <= MAX_ARP_RETRIES) { - i = sizeof(*breq); - - if (sendto(s, breq, i, 0, (struct sockaddr *) server_addr, sizeof(*server_addr)) != i) { - close(s); - log_perror("sendto"); - return -1; - } - - polls.fd = sin; - polls.events = POLLIN; - - while (poll(&polls, 1, timeout*1000) == 1) { - - if ((j = recv(sin, eth_packet, sizeof(eth_packet), 0)) == -1) { - log_perror("recv"); - continue; - } - - /* We need to do some basic sanity checking of the header */ - if (j < (signed)(sizeof(*ip_hdr) + sizeof(*udp_hdr))) - continue; - - ip_hdr = (void *) eth_packet; - if (!verify_checksum(ip_hdr, sizeof(*ip_hdr))) - continue; - - if (ntohs(ip_hdr->tot_len) > j) - continue; - - j = ntohs(ip_hdr->tot_len); - - if (ip_hdr->protocol != IPPROTO_UDP) - continue; - - udp_hdr = (void *) (eth_packet + sizeof(*ip_hdr)); - - if (ntohs(udp_hdr->source) != BOOTP_SERVER_PORT) - continue; - - if (ntohs(udp_hdr->dest) != BOOTP_CLIENT_PORT) - continue; - /* Go on with this packet; it looks sane */ - - /* Originally copied sizeof (*bresp) - this is a security - problem due to a potential underflow of the source - buffer. Also, it trusted that the packet was properly - 0xFF terminated, which is not true in the case of the - DHCP server on Cisco 800 series ISDN router. */ - - memset (bresp, 0xFF, sizeof (*bresp)); - memcpy (bresp, (char *) udp_hdr + sizeof (*udp_hdr), j - sizeof (*ip_hdr) - sizeof (*udp_hdr)); - - /* sanity checks */ - if (bresp->id != breq->id) - continue; - if (bresp->opcode != BOOTP_OPCODE_REPLY) - continue; - if (bresp->hwlength != breq->hwlength) - continue; - if (memcmp(bresp->hwaddr, breq->hwaddr, bresp->hwlength)) - continue; - if (get_vendor_code(bresp, DHCP_OPTION_TYPE, &type) || type != dhcp_type) - continue; - if (memcmp(bresp->vendor, vendor_cookie, 4)) - continue; - return 0; - } - rfc951_sleep(retry); - breq->secs = htons ((currticks () - starttime) / 20); - retry++; - timeout *= 2; - if (timeout > 5) - timeout = 5; - } - - return -1; -} - -static void add_vendor_code(struct bootp_request * breq, unsigned char option, unsigned char length, void * data) -{ - unsigned char * chptr; - int theOption, theLength; - - chptr = breq->vendor; - chptr += 4; - while (*chptr != 0xFF && *chptr != option) { - theOption = *chptr++; - if (!theOption) continue; - theLength = *chptr++; - chptr += theLength; - } - - *chptr++ = option; - *chptr++ = length; - memcpy(chptr, data, length); - chptr[length] = 0xff; -} - - -char * dhcp_hostname = NULL; -char * dhcp_domain = NULL; - -enum return_type perform_dhcp(struct interface_info * intf) -{ - int s, i; - struct sockaddr_in server_addr; - struct sockaddr_in client_addr; - struct sockaddr_in broadcast_addr; - struct bootp_request breq, bresp; - unsigned char messageType; - unsigned int lease; - short aShort; - int num_options; - char requested_options[50]; - char * client_id_str, * client_id_hwaddr; - - if (strncmp(intf->device, "eth", 3)) { - stg1_error_message("DHCP available only for Ethernet networking."); - return RETURN_ERROR; - } - - s = socket(AF_INET, SOCK_DGRAM, 0); - if (s < 0) { - log_perror("socket"); - return RETURN_ERROR; - } - - { - enum return_type results; - char * questions[] = { "Host name", "Domain name", NULL }; - char * questions_auto[] = { "hostname", "domain" }; - static char ** answers = NULL; - char * boulet; - - client_id_str = client_id_hwaddr = NULL; - - results = ask_from_entries_auto("If the DHCP server needs to know you by name; please fill in this information. " - "Valid answers are for example: `mybox' for hostname and `mynetwork.com' for " - "domain name, for a machine called `mybox.mynetwork.com' on the Internet.", - questions, &answers, 32, questions_auto, NULL); - if (results == RETURN_OK) - { - dhcp_hostname = answers[0]; - if ((boulet = strchr(dhcp_hostname, '.')) != NULL) - boulet[0] = '\0'; - dhcp_domain = answers[1]; - - if (*dhcp_hostname && *dhcp_domain) { - /* if we have both, then create client id from them */ - client_id_str = malloc(1 + strlen(dhcp_hostname) + 1 + strlen(dhcp_domain) + 1); - client_id_str[0] = '\0'; - sprintf(client_id_str+1, "%s.%s", dhcp_hostname, dhcp_domain); - } - } - } - - if (initial_setup_interface(intf->device, s) != 0) { - close(s); - return RETURN_ERROR; - } - - if (prepare_request(&breq, s, intf->device) != 0) { - close(s); - return RETURN_ERROR; - } - - messageType = DHCP_TYPE_DISCOVER; - add_vendor_code(&breq, DHCP_OPTION_TYPE, 1, &messageType); - - /* add pieces needed to have DDNS/DHCP IP selection based on requested name */ - if (dhcp_hostname && *dhcp_hostname) { /* pick client id form based on absence or presence of domain name */ - if (*dhcp_domain) /* alternate style <hostname>.<domainname> */ - add_vendor_code(&breq, DHCP_OPTION_CLIENT_IDENTIFIER, strlen(client_id_str+1)+1, client_id_str); - else { /* usual style (aka windows / dhcpcd) */ - /* but put MAC in form required for client identifier first */ - client_id_hwaddr = malloc(IFHWADDRLEN+2); - client_id_hwaddr[0] = 1; /* set flag for ethernet */ - memcpy(client_id_hwaddr+1, gen_hwaddr, IFHWADDRLEN); - add_vendor_code(&breq, DHCP_OPTION_CLIENT_IDENTIFIER, IFHWADDRLEN+1, client_id_hwaddr); - } - /* this is the one that the dhcp server really wants for DDNS updates */ - add_vendor_code(&breq, BOOTP_OPTION_HOSTNAME, strlen(dhcp_hostname), dhcp_hostname); - log_message("DHCP: telling server to use name = %s", dhcp_hostname); - } - - memset(&client_addr.sin_addr, 0, sizeof(&client_addr.sin_addr)); - client_addr.sin_family = AF_INET; - client_addr.sin_port = htons(BOOTP_CLIENT_PORT); /* bootp client */ - - if (bind(s, (struct sockaddr *) &client_addr, sizeof(client_addr))) { - log_perror("bind"); - return RETURN_ERROR; - } - - broadcast_addr.sin_family = AF_INET; - broadcast_addr.sin_port = htons(BOOTP_SERVER_PORT); /* bootp server */ - memset(&broadcast_addr.sin_addr, 0xff, sizeof(broadcast_addr.sin_addr)); /* broadcast */ - - log_message("DHCP: sending DISCOVER"); - - wait_message("Sending DHCP request..."); - i = handle_transaction(s, &breq, &bresp, &broadcast_addr, DHCP_TYPE_OFFER); - remove_wait_message(); - - if (i != 0) { - stg1_error_message("No DHCP reply received."); - close(s); - return RETURN_ERROR; - } - - server_addr.sin_family = AF_INET; - server_addr.sin_port = htons(BOOTP_SERVER_PORT); /* bootp server */ - if (get_vendor_code(&bresp, DHCP_OPTION_SERVER, &server_addr.sin_addr)) { - close(s); - log_message("DHCPOFFER didn't include server address"); - return RETURN_ERROR; - } - - init_vendor_codes(&breq); - messageType = DHCP_TYPE_REQUEST; - add_vendor_code(&breq, DHCP_OPTION_TYPE, 1, &messageType); - add_vendor_code(&breq, DHCP_OPTION_SERVER, 4, &server_addr.sin_addr); - add_vendor_code(&breq, DHCP_OPTION_REQADDR, 4, &bresp.yiaddr); - - /* if used the first time, then have to use it again */ - if (dhcp_hostname && *dhcp_hostname) { /* add pieces needed to have DDNS/DHCP IP selection based on requested name */ - if (dhcp_domain && *dhcp_domain) /* alternate style */ - add_vendor_code(&breq, DHCP_OPTION_CLIENT_IDENTIFIER, strlen(client_id_str+1)+1, client_id_str); - else /* usual style (aka windows / dhcpcd) */ - add_vendor_code(&breq, DHCP_OPTION_CLIENT_IDENTIFIER, IFHWADDRLEN+1, client_id_hwaddr); - /* this is the one that the dhcp server really wants for DDNS updates */ - add_vendor_code(&breq, BOOTP_OPTION_HOSTNAME, strlen(dhcp_hostname), dhcp_hostname); - } - - aShort = ntohs(sizeof(struct bootp_request)); - add_vendor_code(&breq, DHCP_OPTION_MAXSIZE, 2, &aShort); - - num_options = 0; - requested_options[num_options++] = BOOTP_OPTION_NETMASK; - requested_options[num_options++] = BOOTP_OPTION_GATEWAY; - requested_options[num_options++] = BOOTP_OPTION_DNS; - requested_options[num_options++] = BOOTP_OPTION_DOMAIN; - requested_options[num_options++] = BOOTP_OPTION_BROADCAST; - add_vendor_code(&breq, DHCP_OPTION_OPTIONREQ, num_options, requested_options); - - /* request a lease of 1 hour */ - i = htonl(60 * 60); - add_vendor_code(&breq, DHCP_OPTION_LEASE, 4, &i); - - log_message("DHCP: sending REQUEST"); - - i = handle_transaction(s, &breq, &bresp, &broadcast_addr, DHCP_TYPE_ACK); - - if (i != 0) { - close(s); - return RETURN_ERROR; - } - - if (get_vendor_code(&bresp, DHCP_OPTION_LEASE, &lease)) { - log_message("failed to get lease time\n"); - return RETURN_ERROR; - } - lease = ntohl(lease); - - close(s); - - intf->netmask.s_addr = 0; - intf->broadcast.s_addr = 0; - intf->network.s_addr = 0; - - parse_reply(&bresp, intf); - - return RETURN_OK; -} |