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Ping: code cleanup

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This commit is contained in:
Michiel Broek 2002-05-04 17:54:33 +00:00
parent 841b2ec413
commit c4ded8d10b
1 changed files with 46 additions and 38 deletions
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84
mbtask/ping.c
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@ -54,6 +54,9 @@ struct in_addr paddr; /* Current ping address */
/*
* Internal prototypes
*/
static int icmp4_errcmp(char *, int, struct in_addr *, char *, int, int); static int icmp4_errcmp(char *, int, struct in_addr *, char *, int, int);
unsigned short get_rand16(void); unsigned short get_rand16(void);
int ping_send(struct in_addr); int ping_send(struct in_addr);
@ -99,6 +102,12 @@ int ping_receive(struct in_addr);
#define ICMP4_ECHO_LEN ICMP_BASEHDR_LEN #define ICMP4_ECHO_LEN ICMP_BASEHDR_LEN
short p_sequence = 0;
unsigned short id;
struct icmphdr icmpd;
struct sockaddr_in to;
/* /*
* Takes a packet as send out and a recieved ICMP packet and looks whether the ICMP packet is * Takes a packet as send out and a recieved ICMP packet and looks whether the ICMP packet is
@ -108,42 +117,41 @@ int ping_receive(struct in_addr);
* compared of the IP header). The RFC sais that we get at least 8 bytes of the offending packet. * compared of the IP header). The RFC sais that we get at least 8 bytes of the offending packet.
* We do not compare more, as this is all we need. * We do not compare more, as this is all we need.
*/ */
static int icmp4_errcmp(char *packet, int plen, struct in_addr *to, char *errmsg, int elen, int errtype) static int icmp4_errcmp(char *packet, int plen, struct in_addr *too, char *errmsg, int elen, int errtype)
{ {
struct iphdr iph; struct iphdr iph;
struct icmphdr icmph; struct icmphdr icmph;
struct iphdr eiph; struct iphdr eiph;
char *data; char *data;
/* XXX: lots of memcpy to avoid unaligned accesses on alpha */ /*
if (elen < sizeof(struct iphdr)) * lots of memcpy to avoid unaligned accesses on alpha
return 0; */
memcpy(&iph, errmsg, sizeof(iph)); if (elen < sizeof(struct iphdr))
if (iph.ip_p != IPPROTO_ICMP || elen < iph.ip_hl * 4 + ICMP_BASEHDR_LEN + sizeof(eiph)) return 0;
return 0;
memcpy(&icmph, errmsg + iph.ip_hl * 4, ICMP_BASEHDR_LEN); memcpy(&iph, errmsg, sizeof(iph));
memcpy(&eiph, errmsg + iph.ip_hl * 4 + ICMP_BASEHDR_LEN, sizeof(eiph)); if (iph.ip_p != IPPROTO_ICMP || elen < iph.ip_hl * 4 + ICMP_BASEHDR_LEN + sizeof(eiph))
if (elen < iph.ip_hl * 4 + ICMP_BASEHDR_LEN + eiph.ip_hl * 4 + 8) return 0;
return 0;
data = errmsg + iph.ip_hl * 4 + ICMP_BASEHDR_LEN + eiph.ip_hl * 4; memcpy(&icmph, errmsg + iph.ip_hl * 4, ICMP_BASEHDR_LEN);
return icmph.icmp_type == errtype && memcmp(&to->s_addr, &eiph.ip_daddr, sizeof(to->s_addr)) == 0 && memcpy(&eiph, errmsg + iph.ip_hl * 4 + ICMP_BASEHDR_LEN, sizeof(eiph));
memcmp(data, packet, plen < 8 ?plen:8) == 0; if (elen < iph.ip_hl * 4 + ICMP_BASEHDR_LEN + eiph.ip_hl * 4 + 8)
return 0;
data = errmsg + iph.ip_hl * 4 + ICMP_BASEHDR_LEN + eiph.ip_hl * 4;
return icmph.icmp_type == errtype && memcmp(&too->s_addr, &eiph.ip_daddr, sizeof(too->s_addr)) == 0 &&
memcmp(data, packet, plen < 8 ?plen:8) == 0;
} }
unsigned short get_rand16(void) unsigned short get_rand16(void)
{ {
return random()&0xffff; return random()&0xffff;
} }
short p_sequence = 0;
unsigned short id;
struct icmphdr icmpd;
struct sockaddr_in to;
/* /*
* IPv4/ICMPv4 ping. Called from ping (see below) * IPv4/ICMPv4 ping. Called from ping (see below)
@ -172,12 +180,14 @@ int ping_send(struct in_addr addr)
id = (unsigned short)get_rand16(); /* randomize a ping id */ id = (unsigned short)get_rand16(); /* randomize a ping id */
#ifdef __linux__ #ifdef __linux__
/* Fancy ICMP filering -- only on Linux (as far is I know) */ /*
* Fancy ICMP filering -- only on Linux (as far is I know)
/* In fact, there should be macros for treating icmp_filter, but I haven't found them in Linux 2.2.15. *
* So, set it manually and unportable ;-) */ * In fact, there should be macros for treating icmp_filter, but I haven't found them in Linux 2.2.15.
/* This filter lets ECHO_REPLY (0), DEST_UNREACH(3) and TIME_EXCEEDED(11) pass. */ * So, set it manually and unportable ;-)
/* !(0000 1000 0000 1001) = 0xff ff f7 f6 */ * This filter lets ECHO_REPLY (0), DEST_UNREACH(3) and TIME_EXCEEDED(11) pass.
* !(0000 1000 0000 1001) = 0xff ff f7 f6
*/
f.data=0xfffff7f6; f.data=0xfffff7f6;
if (setsockopt(ping_isocket, SOL_RAW, ICMP_FILTER, &f, sizeof(f)) == -1) { if (setsockopt(ping_isocket, SOL_RAW, ICMP_FILTER, &f, sizeof(f)) == -1) {
if (icmp_errs < ICMP_MAX_ERRS) if (icmp_errs < ICMP_MAX_ERRS)
@ -261,7 +271,6 @@ int ping_receive(struct in_addr addr)
memcpy(&icmpp, ((unsigned long int *)buf)+iph.ip_hl, sizeof(icmpp)); memcpy(&icmpp, ((unsigned long int *)buf)+iph.ip_hl, sizeof(icmpp));
if (iph.ip_saddr == addr.s_addr && icmpp.icmp_type == ICMP_ECHOREPLY && if (iph.ip_saddr == addr.s_addr && icmpp.icmp_type == ICMP_ECHOREPLY &&
ntohs(icmpp.icmp_id) == id && ntohs(icmpp.icmp_seq) == p_sequence) { ntohs(icmpp.icmp_id) == id && ntohs(icmpp.icmp_seq) == p_sequence) {
// tasklog('-', "ping: valid reply received, id %d, sequence %d", ntohs(icmpp.icmp_id), ntohs(icmpp.icmp_seq));
return 0; return 0;
} else { } else {
/* No regular echo reply. Maybe an error? */ /* No regular echo reply. Maybe an error? */
@ -292,7 +301,7 @@ int ping_receive(struct in_addr addr)
void check_ping(void) void check_ping(void)
{ {
int rc; int rc = 0;
/* /*
* If the previous pingstat is still P_SENT, then we now consider it a timeout. * If the previous pingstat is still P_SENT, then we now consider it a timeout.
@ -301,13 +310,12 @@ void check_ping(void)
pingresult[pingnr] = FALSE; pingresult[pingnr] = FALSE;
icmp_errs++; icmp_errs++;
if (icmp_errs < ICMP_MAX_ERRS) if (icmp_errs < ICMP_MAX_ERRS)
tasklog('p', "ping %s seq=%d timeout", pingaddress, p_sequence); tasklog('p', "ping: %s seq=%d timeout", pingaddress, p_sequence);
} }
/* /*
* Check internet connection with ICMP ping * Check internet connection with ICMP ping
*/ */
rc = 0;
if (pingnr == 1) { if (pingnr == 1) {
pingnr = 2; pingnr = 2;
if (strlen(TCFG.isp_ping2)) { if (strlen(TCFG.isp_ping2)) {
@ -328,7 +336,7 @@ void check_ping(void)
rc = ping_send(paddr); rc = ping_send(paddr);
if (rc) { if (rc) {
if (icmp_errs++ < ICMP_MAX_ERRS) if (icmp_errs++ < ICMP_MAX_ERRS)
tasklog('?', "ping send %s rc=%d", pingaddress, rc); tasklog('?', "ping: to %s rc=%d", pingaddress, rc);
pingstate = P_FAIL; pingstate = P_FAIL;
pingresult[pingnr] = FALSE; pingresult[pingnr] = FALSE;
} else { } else {
@ -382,8 +390,8 @@ void state_ping(void)
pingstate = P_OK; pingstate = P_OK;
pingresult[pingnr] = TRUE; pingresult[pingnr] = TRUE;
} else { } else {
// if (rc != -6) if (rc != -6)
tasklog('p', "ping recv %s id=%d rc=%d", pingaddress, id, rc); tasklog('p', "ping: recv %s id=%d rc=%d", pingaddress, id, rc);
} }
break; break;
} }