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authorDenis Vlasenko2007-07-03 15:47:50 +0000
committerDenis Vlasenko2007-07-03 15:47:50 +0000
commit42b3dea9bfb8ac595c71089ee23012f44dd43eb2 (patch)
treeb7b86d06a574d2af72bc79536d399905b5619959 /networking/udhcp/arpping.c
parent54e19da86d5496ec5f5787b85a2b6342be1d63d4 (diff)
downloadbusybox-42b3dea9bfb8ac595c71089ee23012f44dd43eb2.zip
busybox-42b3dea9bfb8ac595c71089ee23012f44dd43eb2.tar.gz
udhcp: many small fixes:
* arpping(): smaller and even probably fixed * lots of variables/params converted: ulong -> uint32_t * uptime() nuked in favor of monotonic_sec() * udhcp_get_packet(): only one "bad vendor", simplify function old new delta reservedIp 36 35 -1 udhcpc_main 2462 2460 -2 addStaticLease 64 62 -2 static.broken_vendors 16 - -16 uptime 19 - -19 udhcpd_main 1273 1238 -35 udhcp_get_packet 223 184 -39 .rodata 144162 144106 -56 arpping 690 609 -81 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 0/7 up/down: 0/-251) Total: -251 bytes text data bss dec hex filename 734241 3028 14400 751669 b7835 busybox_old 734005 3028 14400 751433 b7749 busybox_unstripped
Diffstat (limited to 'networking/udhcp/arpping.c')
-rw-r--r--networking/udhcp/arpping.c121
1 files changed, 58 insertions, 63 deletions
diff --git a/networking/udhcp/arpping.c b/networking/udhcp/arpping.c
index 615a911..4ac52c6 100644
--- a/networking/udhcp/arpping.c
+++ b/networking/udhcp/arpping.c
@@ -15,44 +15,36 @@
struct arpMsg {
/* Ethernet header */
- uint8_t h_dest[6]; /* destination ether addr */
- uint8_t h_source[6]; /* source ether addr */
- uint16_t h_proto; /* packet type ID field */
+ uint8_t h_dest[6]; /* 00 destination ether addr */
+ uint8_t h_source[6]; /* 06 source ether addr */
+ uint16_t h_proto; /* 0c packet type ID field */
/* ARP packet */
- uint16_t htype; /* hardware type (must be ARPHRD_ETHER) */
- uint16_t ptype; /* protocol type (must be ETH_P_IP) */
- uint8_t hlen; /* hardware address length (must be 6) */
- uint8_t plen; /* protocol address length (must be 4) */
- uint16_t operation; /* ARP opcode */
- uint8_t sHaddr[6]; /* sender's hardware address */
- uint8_t sInaddr[4]; /* sender's IP address */
- uint8_t tHaddr[6]; /* target's hardware address */
- uint8_t tInaddr[4]; /* target's IP address */
- uint8_t pad[18]; /* pad for min. Ethernet payload (60 bytes) */
+ uint16_t htype; /* 0e hardware type (must be ARPHRD_ETHER) */
+ uint16_t ptype; /* 10 protocol type (must be ETH_P_IP) */
+ uint8_t hlen; /* 12 hardware address length (must be 6) */
+ uint8_t plen; /* 13 protocol address length (must be 4) */
+ uint16_t operation; /* 14 ARP opcode */
+ uint8_t sHaddr[6]; /* 16 sender's hardware address */
+ uint8_t sInaddr[4]; /* 1c sender's IP address */
+ uint8_t tHaddr[6]; /* 20 target's hardware address */
+ uint8_t tInaddr[4]; /* 26 target's IP address */
+ uint8_t pad[18]; /* 2a pad for min. ethernet payload (60 bytes) */
} ATTRIBUTE_PACKED;
-/* args: yiaddr - what IP to ping
- * ip - our ip
- * mac - our arp address
- * interface - interface to use
- * retn: 1 addr free
- * 0 addr used
- * -1 error
- */
-/* FIXME: match response against chaddr */
-int arpping(uint32_t yiaddr, uint32_t ip, uint8_t *mac, char *interface)
-{
- int timeout = 2;
- int s; /* socket */
- int rv = 1; /* return value */
- struct sockaddr addr; /* for interface name */
- struct arpMsg arp;
- fd_set fdset;
- struct timeval tm;
- time_t prevTime;
+/* Returns 1 if no reply received */
+int arpping(uint32_t test_ip, uint32_t from_ip, uint8_t *from_mac, const char *interface)
+{
+ int timeout = 2;
+ int s; /* socket */
+ int rv = 1; /* "no reply received" yet */
+ struct sockaddr addr; /* for interface name */
+ struct arpMsg arp;
+ fd_set fdset;
+ struct timeval tm;
+ unsigned prevTime;
s = socket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP));
if (s == -1) {
@@ -62,55 +54,58 @@ int arpping(uint32_t yiaddr, uint32_t ip, uint8_t *mac, char *interface)
if (setsockopt_broadcast(s) == -1) {
bb_perror_msg("cannot setsocketopt on raw socket");
- close(s);
- return -1;
+ goto ret;
}
/* send arp request */
memset(&arp, 0, sizeof(arp));
- memcpy(arp.h_dest, MAC_BCAST_ADDR, 6); /* MAC DA */
- memcpy(arp.h_source, mac, 6); /* MAC SA */
- arp.h_proto = htons(ETH_P_ARP); /* protocol type (Ethernet) */
- arp.htype = htons(ARPHRD_ETHER); /* hardware type */
- arp.ptype = htons(ETH_P_IP); /* protocol type (ARP message) */
- arp.hlen = 6; /* hardware address length */
- arp.plen = 4; /* protocol address length */
- arp.operation = htons(ARPOP_REQUEST); /* ARP op code */
- memcpy(arp.sInaddr, &ip, sizeof(ip)); /* source IP address */
- memcpy(arp.sHaddr, mac, 6); /* source hardware address */
- memcpy(arp.tInaddr, &yiaddr, sizeof(yiaddr)); /* target IP address */
+ memset(arp.h_dest, 0xff, 6); /* MAC DA */
+ memcpy(arp.h_source, from_mac, 6); /* MAC SA */
+ arp.h_proto = htons(ETH_P_ARP); /* protocol type (Ethernet) */
+ arp.htype = htons(ARPHRD_ETHER); /* hardware type */
+ arp.ptype = htons(ETH_P_IP); /* protocol type (ARP message) */
+ arp.hlen = 6; /* hardware address length */
+ arp.plen = 4; /* protocol address length */
+ arp.operation = htons(ARPOP_REQUEST); /* ARP op code */
+ memcpy(arp.sHaddr, from_mac, 6); /* source hardware address */
+ memcpy(arp.sInaddr, &from_ip, sizeof(from_ip)); /* source IP address */
+ /* tHaddr */ /* target hardware address */
+ memcpy(arp.tInaddr, &test_ip, sizeof(test_ip)); /* target IP address */
memset(&addr, 0, sizeof(addr));
- strcpy(addr.sa_data, interface);
+ safe_strncpy(addr.sa_data, interface, sizeof(addr.sa_data));
if (sendto(s, &arp, sizeof(arp), 0, &addr, sizeof(addr)) < 0)
- rv = 0;
+ goto ret;
- /* wait arp reply, and check it */
- tm.tv_usec = 0;
- prevTime = uptime();
- while (timeout > 0) {
+ /* wait for arp reply, and check it */
+ do {
+ int r;
+ prevTime = monotonic_sec();
FD_ZERO(&fdset);
FD_SET(s, &fdset);
tm.tv_sec = timeout;
- if (select(s + 1, &fdset, (fd_set *) NULL, (fd_set *) NULL, &tm) < 0) {
+ tm.tv_usec = 0;
+ r = select(s + 1, &fdset, NULL, NULL, &tm);
+ if (r < 0) {
bb_perror_msg("error on ARPING request");
if (errno != EINTR)
- rv = 0;
- } else if (FD_ISSET(s, &fdset)) {
+ break;
+ } else if (r) {
if (recv(s, &arp, sizeof(arp), 0) < 0)
- rv = 0;
- if (arp.operation == htons(ARPOP_REPLY) &&
- memcmp(arp.tHaddr, mac, 6) == 0 &&
- *((uint32_t *) arp.sInaddr) == yiaddr) {
- DEBUG("Valid arp reply received for this address");
+ break;
+ if (arp.operation == htons(ARPOP_REPLY)
+ && memcmp(arp.tHaddr, from_mac, 6) == 0
+ && *((uint32_t *) arp.sInaddr) == test_ip
+ ) {
rv = 0;
break;
}
}
- timeout -= uptime() - prevTime;
- prevTime = uptime();
- }
+ timeout -= monotonic_sec() - prevTime;
+ } while (timeout > 0);
+
+ ret:
close(s);
- DEBUG("%salid arp replies for this address", rv ? "No v" : "V");
+ DEBUG("%srp reply received for this address", rv ? "No a" : "A");
return rv;
}