arpping() no longer blocks and address verification via arp is now performed
asynchronously in the main event loop.
This commit is contained in:
parent
a154f96538
commit
e37ed0e16b
115
ndhc/arpping.c
115
ndhc/arpping.c
@ -1,5 +1,5 @@
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/*
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/*
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* Shamelessly ripped off from busybox's udhcpc variant, which in turn was...
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* Derived from busybox's udhcpc variant, which in turn was...
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* Mostly stolen from: dhcpcd - DHCP client daemon
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* Mostly stolen from: dhcpcd - DHCP client daemon
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* by Yoichi Hariguchi <yoichi@fore.com>
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* by Yoichi Hariguchi <yoichi@fore.com>
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* Licensed under GPLv2, see file LICENSE in this source tree.
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* Licensed under GPLv2, see file LICENSE in this source tree.
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@ -9,59 +9,14 @@
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#include <sys/types.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/socket.h>
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#include <netinet/if_ether.h>
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#include <netinet/if_ether.h>
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#include <net/if_arp.h>
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#include <sys/time.h>
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#include <sys/time.h>
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#include <errno.h>
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#include <errno.h>
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#include <poll.h>
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#include "arpping.h"
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#include "dhcpd.h"
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#include "dhcpd.h"
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#include "log.h"
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#include "log.h"
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#include "strl.h"
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#include "strl.h"
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#include "io.h"
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#include "io.h"
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struct arpMsg {
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/* Ethernet header */
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uint8_t h_dest[6]; /* 00 destination ether addr */
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uint8_t h_source[6]; /* 06 source ether addr */
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uint16_t h_proto; /* 0c packet type ID field */
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/* ARP packet */
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uint16_t htype; /* 0e hardware type (must be ARPHRD_ETHER) */
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uint16_t ptype; /* 10 protocol type (must be ETH_P_IP) */
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uint8_t hlen; /* 12 hardware address length (must be 6) */
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uint8_t plen; /* 13 protocol address length (must be 4) */
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uint16_t operation; /* 14 ARP opcode */
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uint8_t sHaddr[6]; /* 16 sender's hardware address */
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uint8_t sInaddr[4]; /* 1c sender's IP address */
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uint8_t tHaddr[6]; /* 20 target's hardware address */
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uint8_t tInaddr[4]; /* 26 target's IP address */
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uint8_t pad[18]; /* 2a pad for min. ethernet payload (60 bytes) */
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};
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enum {
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ARP_MSG_SIZE = 0x2a
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};
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static int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout)
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{
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while (1) {
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int n = poll(ufds, nfds, timeout);
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if (n >= 0)
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return n;
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/* Make sure we inch towards completion */
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if (timeout > 0)
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timeout--;
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/* E.g. strace causes poll to return this */
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if (errno == EINTR)
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continue;
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/* Kernel is very low on memory. Retry. */
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/* I doubt many callers would handle this correctly! */
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if (errno == ENOMEM)
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continue;
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log_warning("poll error: %s", strerror(errno));
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return n;
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}
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}
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static unsigned long long curms()
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static unsigned long long curms()
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{
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{
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struct timeval tv;
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struct timeval tv;
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@ -69,27 +24,26 @@ static unsigned long long curms()
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return tv.tv_sec * 1000ULL + tv.tv_usec / 1000ULL;
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return tv.tv_sec * 1000ULL + tv.tv_usec / 1000ULL;
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}
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}
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/* Returns 1 if no reply received */
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/* Returns fd of the arp socket, or -1 on failure. */
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int arpping(uint32_t test_nip, const uint8_t *safe_mac, uint32_t from_ip,
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int arpping(uint32_t test_nip, const uint8_t *safe_mac, uint32_t from_ip,
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uint8_t *from_mac, const char *interface)
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uint8_t *from_mac, const char *interface)
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{
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{
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int timeout_ms;
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int arpfd;
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struct pollfd pfd[1];
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int rv = 1; /* "no reply received" yet */
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int opt = 1;
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int opt = 1;
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struct sockaddr addr; /* for interface name */
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struct sockaddr addr; /* for interface name */
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struct arpMsg arp;
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struct arpMsg arp;
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pfd[0].fd = socket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP));
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arpfd = socket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP));
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if (pfd[0].fd == -1) {
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if (arpfd == -1) {
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log_warning("arpping: failed to create socket: %s", strerror(errno));
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log_warning("arpping: failed to create socket: %s", strerror(errno));
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return -1;
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return -1;
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}
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}
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if (setsockopt(pfd[0].fd, SOL_SOCKET, SO_BROADCAST,
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if (setsockopt(arpfd, SOL_SOCKET, SO_BROADCAST,
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&opt, sizeof opt) == -1) {
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&opt, sizeof opt) == -1) {
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log_warning("arpping: failed to set broadcast: %s", strerror(errno));
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log_warning("arpping: failed to set broadcast: %s", strerror(errno));
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goto ret;
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close(arpfd);
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return -1;
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}
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}
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/* send arp request */
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/* send arp request */
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@ -103,58 +57,17 @@ int arpping(uint32_t test_nip, const uint8_t *safe_mac, uint32_t from_ip,
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arp.plen = 4; /* protocol address length */
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arp.plen = 4; /* protocol address length */
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arp.operation = htons(ARPOP_REQUEST); /* ARP op code */
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arp.operation = htons(ARPOP_REQUEST); /* ARP op code */
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memcpy(arp.sHaddr, from_mac, 6); /* source hardware address */
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memcpy(arp.sHaddr, from_mac, 6); /* source hardware address */
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memcpy(arp.sInaddr, &from_ip, sizeof from_ip); /* source IP address */
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memcpy(arp.sInaddr, &from_ip, sizeof from_ip); /* source IP address */
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/* tHaddr is zero-filled */ /* target hardware address */
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/* tHaddr is zero-filled */ /* target hardware address */
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memcpy(arp.tInaddr, &test_nip, sizeof test_nip);/* target IP address */
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memcpy(arp.tInaddr, &test_nip, sizeof test_nip);/* target IP address */
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memset(&addr, 0, sizeof addr);
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memset(&addr, 0, sizeof addr);
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strlcpy(addr.sa_data, interface, sizeof addr.sa_data);
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strlcpy(addr.sa_data, interface, sizeof addr.sa_data);
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if (safe_sendto(pfd[0].fd, (const char *)&arp, sizeof arp,
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if (safe_sendto(arpfd, (const char *)&arp, sizeof arp,
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0, &addr, sizeof addr) < 0) {
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0, &addr, sizeof addr) < 0) {
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log_error("arpping: sendto failed: %s", strerror(errno));
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log_error("arpping: sendto failed: %s", strerror(errno));
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goto ret;
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close(arpfd);
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return -1;
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}
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}
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return arpfd;
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/* wait for arp reply, and check it */
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timeout_ms = 2000;
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do {
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typedef uint32_t aliased_uint32_t __attribute__((__may_alias__));
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int r;
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unsigned long long prevTime = curms();
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pfd[0].events = POLLIN;
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r = safe_poll(pfd, 1, timeout_ms);
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if (r < 0)
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break;
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if (r) {
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r = safe_read(pfd[0].fd, (char *)&arp, sizeof arp);
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if (r < 0)
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break;
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//log3("sHaddr %02x:%02x:%02x:%02x:%02x:%02x",
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//arp.sHaddr[0], arp.sHaddr[1], arp.sHaddr[2],
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//arp.sHaddr[3], arp.sHaddr[4], arp.sHaddr[5]);
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if (r >= ARP_MSG_SIZE
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&& arp.operation == htons(ARPOP_REPLY)
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/* don't check it: Linux doesn't return proper tHaddr (fixed in 2.6.24?) */
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/* && memcmp(arp.tHaddr, from_mac, 6) == 0 */
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&& *(aliased_uint32_t*)arp.sInaddr == test_nip
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) {
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/* if ARP source MAC matches safe_mac
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* (which is client's MAC), then it's not a conflict
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* (client simply already has this IP and replies to ARPs!)
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*/
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if (!safe_mac || memcmp(safe_mac, arp.sHaddr, 6) != 0)
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rv = 0;
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break;
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}
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}
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timeout_ms -= (int)(curms() - prevTime);
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} while (timeout_ms > 0);
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ret:
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close(pfd[0].fd);
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log_line("%srp reply received for this address", rv ? "No a" : "A");
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return rv;
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}
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}
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@ -1,8 +1,33 @@
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#ifndef ARPPING_H_
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#ifndef ARPPING_H_
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#define ARPPING_H_
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#define ARPPING_H_
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#include <stdint.h>
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#include <net/if_arp.h>
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struct arpMsg {
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/* Ethernet header */
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uint8_t h_dest[6]; /* 00 destination ether addr */
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uint8_t h_source[6]; /* 06 source ether addr */
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uint16_t h_proto; /* 0c packet type ID field */
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/* ARP packet */
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uint16_t htype; /* 0e hardware type (must be ARPHRD_ETHER) */
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uint16_t ptype; /* 10 protocol type (must be ETH_P_IP) */
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uint8_t hlen; /* 12 hardware address length (must be 6) */
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uint8_t plen; /* 13 protocol address length (must be 4) */
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uint16_t operation; /* 14 ARP opcode */
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uint8_t sHaddr[6]; /* 16 sender's hardware address */
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uint8_t sInaddr[4]; /* 1c sender's IP address */
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uint8_t tHaddr[6]; /* 20 target's hardware address */
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uint8_t tInaddr[4]; /* 26 target's IP address */
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uint8_t pad[18]; /* 2a pad for min. ethernet payload (60 bytes) */
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};
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enum {
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ARP_MSG_SIZE = 0x2a
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};
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int arpping(uint32_t test_nip, const uint8_t *safe_mac, uint32_t from_ip,
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int arpping(uint32_t test_nip, const uint8_t *safe_mac, uint32_t from_ip,
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uint8_t *from_mac, const char *interface);
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uint8_t *from_mac, const char *interface);
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#endif /* ARPPING_H_ */
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#endif /* ARPPING_H_ */
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@ -7,6 +7,7 @@ enum {
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BOUND,
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BOUND,
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RENEWING,
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RENEWING,
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REBINDING,
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REBINDING,
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ARP_CHECK,
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INIT_REBOOT,
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INIT_REBOOT,
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RENEW_REQUESTED,
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RENEW_REQUESTED,
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RELEASED
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RELEASED
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196
ndhc/ndhc.c
196
ndhc/ndhc.c
@ -56,19 +56,20 @@
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#include "strl.h"
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#include "strl.h"
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#include "pidfile.h"
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#include "pidfile.h"
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#include "malloc.h"
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#include "malloc.h"
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#include "io.h"
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#define VERSION "1.0"
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#define VERSION "1.0"
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#define NUMPACKETS 3 /* number of packets to send before delay */
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#define NUMPACKETS 3 /* number of packets to send before delay */
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#define RETRY_DELAY 30 /* time in seconds to delay after sending NUMPACKETS */
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#define RETRY_DELAY 30 /* time in seconds to delay after sending NUMPACKETS */
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static int epollfd, signalFd;
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static int epollfd, signalFd, arpFd = -1;
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static struct epoll_event events[3];
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static struct epoll_event events[3];
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static char pidfile[MAX_PATH_LENGTH] = PID_FILE_DEFAULT;
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static char pidfile[MAX_PATH_LENGTH] = PID_FILE_DEFAULT;
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static uint32_t requested_ip, server_addr, timeout;
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static uint32_t requested_ip, server_addr, timeout;
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static uint32_t lease, t1, t2, xid, start;
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static uint32_t lease, t1, t2, xid, start;
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static int state, packet_num, listenFd, listen_mode;
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static int dhcp_state, arp_prev_dhcp_state, packet_num, listenFd, listen_mode;
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enum {
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enum {
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LISTEN_NONE,
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LISTEN_NONE,
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@ -167,19 +168,26 @@ static void change_listen_mode(int new_mode)
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static void perform_renew(void)
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static void perform_renew(void)
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{
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{
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log_line("Performing a DHCP renew...");
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log_line("Performing a DHCP renew...");
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switch (state) {
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retry:
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switch (dhcp_state) {
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case BOUND:
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case BOUND:
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change_listen_mode(LISTEN_KERNEL);
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change_listen_mode(LISTEN_KERNEL);
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case ARP_CHECK:
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// Cancel arp ping in progress and treat as previous state.
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epoll_del(arpFd);
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arpFd = -1;
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dhcp_state = arp_prev_dhcp_state;
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goto retry;
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case RENEWING:
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case RENEWING:
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case REBINDING:
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case REBINDING:
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state = RENEW_REQUESTED;
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dhcp_state = RENEW_REQUESTED;
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break;
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break;
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case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
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case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
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run_script(NULL, SCRIPT_DECONFIG);
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run_script(NULL, SCRIPT_DECONFIG);
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case REQUESTING:
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case REQUESTING:
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case RELEASED:
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case RELEASED:
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change_listen_mode(LISTEN_RAW);
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change_listen_mode(LISTEN_RAW);
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state = INIT_SELECTING;
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dhcp_state = INIT_SELECTING;
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break;
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break;
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case INIT_SELECTING:
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case INIT_SELECTING:
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break;
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break;
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@ -199,7 +207,8 @@ static void perform_release(void)
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struct in_addr temp_saddr, temp_raddr;
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struct in_addr temp_saddr, temp_raddr;
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/* send release packet */
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/* send release packet */
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if (state == BOUND || state == RENEWING || state == REBINDING) {
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if (dhcp_state == BOUND || dhcp_state == RENEWING ||
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dhcp_state == REBINDING || dhcp_state == ARP_CHECK) {
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temp_saddr.s_addr = server_addr;
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temp_saddr.s_addr = server_addr;
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temp_raddr.s_addr = requested_ip;
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temp_raddr.s_addr = requested_ip;
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log_line("Unicasting a release of %s to %s.",
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log_line("Unicasting a release of %s to %s.",
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@ -209,8 +218,12 @@ static void perform_release(void)
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}
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}
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log_line("Entering released state.");
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log_line("Entering released state.");
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if (dhcp_state == ARP_CHECK) {
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epoll_del(arpFd);
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arpFd = -1;
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}
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change_listen_mode(LISTEN_NONE);
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change_listen_mode(LISTEN_NONE);
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state = RELEASED;
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dhcp_state = RELEASED;
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timeout = 0x7fffffff;
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timeout = 0x7fffffff;
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}
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}
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@ -229,12 +242,63 @@ static void background(void)
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write_pid(pidfile);
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write_pid(pidfile);
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}
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}
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static struct arpMsg arpreply;
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static int arpreply_offset;
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static struct dhcpMessage arp_dhcp_packet;
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static void arp_failed(void)
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{
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log_line("Offered address is in use: declining.");
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epoll_del(arpFd);
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arpFd = -1;
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send_decline(xid, server_addr, arp_dhcp_packet.yiaddr);
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if (arp_prev_dhcp_state != REQUESTING)
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run_script(NULL, SCRIPT_DECONFIG);
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dhcp_state = INIT_SELECTING;
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requested_ip = 0;
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timeout = time(0);
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packet_num = 0;
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change_listen_mode(LISTEN_RAW);
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}
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static void arp_success(void)
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{
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struct in_addr temp_addr;
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epoll_del(arpFd);
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arpFd = -1;
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/* enter bound state */
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t1 = lease >> 1;
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/* little fixed point for n * .875 */
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t2 = (lease * 0x7) >> 3;
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temp_addr.s_addr = arp_dhcp_packet.yiaddr;
|
||||||
|
log_line("Lease of %s obtained, lease time %ld.",
|
||||||
|
inet_ntoa(temp_addr), lease);
|
||||||
|
start = time(0);
|
||||||
|
timeout = t1 + start;
|
||||||
|
requested_ip = arp_dhcp_packet.yiaddr;
|
||||||
|
run_script(&arp_dhcp_packet,
|
||||||
|
((arp_prev_dhcp_state == RENEWING ||
|
||||||
|
arp_prev_dhcp_state == REBINDING)
|
||||||
|
? SCRIPT_RENEW : SCRIPT_BOUND));
|
||||||
|
|
||||||
|
dhcp_state = BOUND;
|
||||||
|
change_listen_mode(LISTEN_NONE);
|
||||||
|
if (client_config.quit_after_lease)
|
||||||
|
exit(EXIT_SUCCESS);
|
||||||
|
if (!client_config.foreground)
|
||||||
|
background();
|
||||||
|
}
|
||||||
|
|
||||||
/* Handle select timeout dropping to zero */
|
/* Handle select timeout dropping to zero */
|
||||||
static void handle_timeout(void)
|
static void handle_timeout(void)
|
||||||
{
|
{
|
||||||
time_t now = time(0);
|
time_t now = time(0);
|
||||||
|
|
||||||
switch (state) {
|
switch (dhcp_state) {
|
||||||
case INIT_SELECTING:
|
case INIT_SELECTING:
|
||||||
if (packet_num < NUMPACKETS) {
|
if (packet_num < NUMPACKETS) {
|
||||||
if (packet_num == 0)
|
if (packet_num == 0)
|
||||||
@ -261,7 +325,7 @@ static void handle_timeout(void)
|
|||||||
case REQUESTING:
|
case REQUESTING:
|
||||||
if (packet_num < NUMPACKETS) {
|
if (packet_num < NUMPACKETS) {
|
||||||
/* send request packet */
|
/* send request packet */
|
||||||
if (state == RENEW_REQUESTED)
|
if (dhcp_state == RENEW_REQUESTED)
|
||||||
/* unicast */
|
/* unicast */
|
||||||
send_renew(xid, server_addr, requested_ip);
|
send_renew(xid, server_addr, requested_ip);
|
||||||
else
|
else
|
||||||
@ -271,9 +335,9 @@ static void handle_timeout(void)
|
|||||||
packet_num++;
|
packet_num++;
|
||||||
} else {
|
} else {
|
||||||
/* timed out, go back to init state */
|
/* timed out, go back to init state */
|
||||||
if (state == RENEW_REQUESTED)
|
if (dhcp_state == RENEW_REQUESTED)
|
||||||
run_script(NULL, SCRIPT_DECONFIG);
|
run_script(NULL, SCRIPT_DECONFIG);
|
||||||
state = INIT_SELECTING;
|
dhcp_state = INIT_SELECTING;
|
||||||
timeout = now;
|
timeout = now;
|
||||||
packet_num = 0;
|
packet_num = 0;
|
||||||
change_listen_mode(LISTEN_RAW);
|
change_listen_mode(LISTEN_RAW);
|
||||||
@ -281,7 +345,7 @@ static void handle_timeout(void)
|
|||||||
break;
|
break;
|
||||||
case BOUND:
|
case BOUND:
|
||||||
/* Lease is starting to run out, time to enter renewing state */
|
/* Lease is starting to run out, time to enter renewing state */
|
||||||
state = RENEWING;
|
dhcp_state = RENEWING;
|
||||||
change_listen_mode(LISTEN_KERNEL);
|
change_listen_mode(LISTEN_KERNEL);
|
||||||
log_line("Entering renew state.");
|
log_line("Entering renew state.");
|
||||||
/* fall right through */
|
/* fall right through */
|
||||||
@ -289,7 +353,7 @@ static void handle_timeout(void)
|
|||||||
/* Either set a new T1, or enter REBINDING state */
|
/* Either set a new T1, or enter REBINDING state */
|
||||||
if ((t2 - t1) <= (lease / 14400 + 1)) {
|
if ((t2 - t1) <= (lease / 14400 + 1)) {
|
||||||
/* timed out, enter rebinding state */
|
/* timed out, enter rebinding state */
|
||||||
state = REBINDING;
|
dhcp_state = REBINDING;
|
||||||
timeout = now + (t2 - t1);
|
timeout = now + (t2 - t1);
|
||||||
log_line("Entering rebinding state.");
|
log_line("Entering rebinding state.");
|
||||||
} else {
|
} else {
|
||||||
@ -304,7 +368,7 @@ static void handle_timeout(void)
|
|||||||
/* Either set a new T2, or enter INIT state */
|
/* Either set a new T2, or enter INIT state */
|
||||||
if ((lease - t2) <= (lease / 14400 + 1)) {
|
if ((lease - t2) <= (lease / 14400 + 1)) {
|
||||||
/* timed out, enter init state */
|
/* timed out, enter init state */
|
||||||
state = INIT_SELECTING;
|
dhcp_state = INIT_SELECTING;
|
||||||
log_line("Lease lost, entering init state.");
|
log_line("Lease lost, entering init state.");
|
||||||
run_script(NULL, SCRIPT_DECONFIG);
|
run_script(NULL, SCRIPT_DECONFIG);
|
||||||
timeout = now;
|
timeout = now;
|
||||||
@ -322,6 +386,45 @@ static void handle_timeout(void)
|
|||||||
/* yah, I know, *you* say it would never happen */
|
/* yah, I know, *you* say it would never happen */
|
||||||
timeout = 0x7fffffff;
|
timeout = 0x7fffffff;
|
||||||
break;
|
break;
|
||||||
|
case ARP_CHECK:
|
||||||
|
arp_failed();
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
typedef uint32_t aliased_uint32_t __attribute__((__may_alias__));
|
||||||
|
static void handle_arp_response(void)
|
||||||
|
{
|
||||||
|
if (arpreply_offset < sizeof arpreply) {
|
||||||
|
int r = safe_read(arpFd, (char *)&arpreply + arpreply_offset,
|
||||||
|
sizeof arpreply - arpreply_offset);
|
||||||
|
if (r < 0) {
|
||||||
|
arp_failed();
|
||||||
|
return;
|
||||||
|
} else
|
||||||
|
arpreply_offset += r;
|
||||||
|
}
|
||||||
|
|
||||||
|
//log3("sHaddr %02x:%02x:%02x:%02x:%02x:%02x",
|
||||||
|
//arp.sHaddr[0], arp.sHaddr[1], arp.sHaddr[2],
|
||||||
|
//arp.sHaddr[3], arp.sHaddr[4], arp.sHaddr[5]);
|
||||||
|
|
||||||
|
if (arpreply_offset >= ARP_MSG_SIZE) {
|
||||||
|
if (arpreply.operation == htons(ARPOP_REPLY)
|
||||||
|
/* don't check: Linux returns invalid tHaddr (fixed in 2.6.24?) */
|
||||||
|
/* && memcmp(arp.tHaddr, from_mac, 6) == 0 */
|
||||||
|
&& *(aliased_uint32_t*)arpreply.sInaddr == arp_dhcp_packet.yiaddr)
|
||||||
|
{
|
||||||
|
/* if ARP source MAC matches safe_mac
|
||||||
|
* (which is client's MAC), then it's not a conflict
|
||||||
|
* (client simply already has this IP and replies to ARPs!)
|
||||||
|
*/
|
||||||
|
/* if (memcmp(safe_mac, arp.sHaddr, 6) == 0) */
|
||||||
|
arp_success();
|
||||||
|
} else {
|
||||||
|
memset(&arpreply, 0, sizeof arpreply);
|
||||||
|
arpreply_offset = 0;
|
||||||
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
@ -329,7 +432,6 @@ static void handle_packet(void)
|
|||||||
{
|
{
|
||||||
unsigned char *temp = NULL, *message = NULL;
|
unsigned char *temp = NULL, *message = NULL;
|
||||||
int len;
|
int len;
|
||||||
struct in_addr temp_addr;
|
|
||||||
struct dhcpMessage packet;
|
struct dhcpMessage packet;
|
||||||
|
|
||||||
if (listen_mode == LISTEN_KERNEL)
|
if (listen_mode == LISTEN_KERNEL)
|
||||||
@ -359,7 +461,7 @@ static void handle_packet(void)
|
|||||||
}
|
}
|
||||||
|
|
||||||
time_t now = time(0);
|
time_t now = time(0);
|
||||||
switch (state) {
|
switch (dhcp_state) {
|
||||||
case INIT_SELECTING:
|
case INIT_SELECTING:
|
||||||
/* Must be a DHCPOFFER to one of our xid's */
|
/* Must be a DHCPOFFER to one of our xid's */
|
||||||
if (*message == DHCPOFFER) {
|
if (*message == DHCPOFFER) {
|
||||||
@ -370,7 +472,7 @@ static void handle_packet(void)
|
|||||||
requested_ip = packet.yiaddr;
|
requested_ip = packet.yiaddr;
|
||||||
|
|
||||||
/* enter requesting state */
|
/* enter requesting state */
|
||||||
state = REQUESTING;
|
dhcp_state = REQUESTING;
|
||||||
timeout = now;
|
timeout = now;
|
||||||
packet_num = 0;
|
packet_num = 0;
|
||||||
} else {
|
} else {
|
||||||
@ -378,6 +480,11 @@ static void handle_packet(void)
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
break;
|
break;
|
||||||
|
case ARP_CHECK:
|
||||||
|
/* We ignore dhcp packets for now. This state will
|
||||||
|
* be changed by the callback for arp ping.
|
||||||
|
*/
|
||||||
|
break;
|
||||||
case RENEW_REQUESTED:
|
case RENEW_REQUESTED:
|
||||||
case REQUESTING:
|
case REQUESTING:
|
||||||
case RENEWING:
|
case RENEWING:
|
||||||
@ -396,54 +503,29 @@ static void handle_packet(void)
|
|||||||
lease = RETRY_DELAY;
|
lease = RETRY_DELAY;
|
||||||
}
|
}
|
||||||
|
|
||||||
if (!arpping(packet.yiaddr, NULL, 0, client_config.arp,
|
arp_prev_dhcp_state = dhcp_state;
|
||||||
client_config.interface)) {
|
dhcp_state = ARP_CHECK;
|
||||||
log_line("Offered address is in use: declining.");
|
memcpy(&arp_dhcp_packet, &packet, sizeof packet);
|
||||||
send_decline(xid, server_addr, packet.yiaddr);
|
arpFd = arpping(arp_dhcp_packet.yiaddr, NULL, 0,
|
||||||
|
client_config.arp, client_config.interface);
|
||||||
if (state != REQUESTING)
|
epoll_add(arpFd);
|
||||||
run_script(NULL, SCRIPT_DECONFIG);
|
timeout = now + 2;
|
||||||
state = INIT_SELECTING;
|
memset(&arpreply, 0, sizeof arpreply);
|
||||||
requested_ip = 0;
|
arpreply_offset = 0;
|
||||||
timeout = now;
|
// Can transition to BOUND or INIT_SELECTING.
|
||||||
packet_num = 0;
|
|
||||||
change_listen_mode(LISTEN_RAW);
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* enter bound state */
|
|
||||||
t1 = lease >> 1;
|
|
||||||
|
|
||||||
/* little fixed point for n * .875 */
|
|
||||||
t2 = (lease * 0x7) >> 3;
|
|
||||||
temp_addr.s_addr = packet.yiaddr;
|
|
||||||
log_line("Lease of %s obtained, lease time %ld.",
|
|
||||||
inet_ntoa(temp_addr), lease);
|
|
||||||
start = now;
|
|
||||||
timeout = t1 + start;
|
|
||||||
requested_ip = packet.yiaddr;
|
|
||||||
run_script(&packet,
|
|
||||||
((state == RENEWING || state == REBINDING)
|
|
||||||
? SCRIPT_RENEW : SCRIPT_BOUND));
|
|
||||||
|
|
||||||
state = BOUND;
|
|
||||||
change_listen_mode(LISTEN_NONE);
|
|
||||||
if (client_config.quit_after_lease)
|
|
||||||
exit(EXIT_SUCCESS);
|
|
||||||
if (!client_config.foreground)
|
|
||||||
background();
|
|
||||||
|
|
||||||
} else if (*message == DHCPNAK) {
|
} else if (*message == DHCPNAK) {
|
||||||
/* return to init state */
|
/* return to init state */
|
||||||
log_line("Received DHCP NAK.");
|
log_line("Received DHCP NAK.");
|
||||||
run_script(&packet, SCRIPT_NAK);
|
run_script(&packet, SCRIPT_NAK);
|
||||||
if (state != REQUESTING)
|
if (dhcp_state != REQUESTING)
|
||||||
run_script(NULL, SCRIPT_DECONFIG);
|
run_script(NULL, SCRIPT_DECONFIG);
|
||||||
state = INIT_SELECTING;
|
dhcp_state = INIT_SELECTING;
|
||||||
timeout = now;
|
timeout = now;
|
||||||
requested_ip = 0;
|
requested_ip = 0;
|
||||||
packet_num = 0;
|
packet_num = 0;
|
||||||
change_listen_mode(LISTEN_RAW);
|
change_listen_mode(LISTEN_RAW);
|
||||||
|
// XXX: this isn't rfc compliant: should be exp backoff
|
||||||
sleep(3); /* avoid excessive network traffic */
|
sleep(3); /* avoid excessive network traffic */
|
||||||
}
|
}
|
||||||
break;
|
break;
|
||||||
@ -528,6 +610,8 @@ static void do_work(void)
|
|||||||
signal_dispatch();
|
signal_dispatch();
|
||||||
else if (fd == listenFd)
|
else if (fd == listenFd)
|
||||||
handle_packet();
|
handle_packet();
|
||||||
|
else if (fd == arpFd)
|
||||||
|
handle_arp_response();
|
||||||
else
|
else
|
||||||
suicide("epoll_wait: unknown fd");
|
suicide("epoll_wait: unknown fd");
|
||||||
}
|
}
|
||||||
@ -669,7 +753,7 @@ int main(int argc, char **argv)
|
|||||||
"cap_net_bind_service,cap_net_broadcast,cap_net_raw=ep");
|
"cap_net_bind_service,cap_net_broadcast,cap_net_raw=ep");
|
||||||
drop_root(uid, gid);
|
drop_root(uid, gid);
|
||||||
|
|
||||||
state = INIT_SELECTING;
|
dhcp_state = INIT_SELECTING;
|
||||||
run_script(NULL, SCRIPT_DECONFIG);
|
run_script(NULL, SCRIPT_DECONFIG);
|
||||||
|
|
||||||
do_work();
|
do_work();
|
||||||
|
Loading…
Reference in New Issue
Block a user