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Fix htonl on 64-bit values #1

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Merged
troglobit merged 2 commits into from
Dec 4, 2025
Merged

Fix htonl on 64-bit values #1

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a787d4f
Fix htonl on 64-bit values
marek22k Dec 4, 2025
f465974
Refactor: Extract packet encoding functions
marek22k Dec 4, 2025
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59 changes: 50 additions & 9 deletions mping.c
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Original file line number Diff line number Diff line change
Expand Up @@ -48,6 +48,14 @@
#define dbg(fmt,args...) do { if (debug) printf(fmt "\n", ##args); } while (0)
#define sig(s,c) do { struct sigaction a = {.sa_handler=c};sigaction(s,&a,0); } while(0)

#if __BIG_ENDIAN__
# define htonll(x) (x)
# define ntohll(x) (x)
#else
# define htonll(x) (((uint64_t)htonl((x) & 0xFFFFFFFF) << 32) | htonl((x) >> 32))
# define ntohll(x) (((uint64_t)ntohl((x) & 0xFFFFFFFF) << 32) | ntohl((x) >> 32))
#endif

#define MC_GROUP_DEFAULT "225.1.2.3"
#define MC_GROUP_INET6 "ff2e::42"
#define MC_PORT_DEFAULT 4321
Expand Down Expand Up @@ -369,6 +377,36 @@ char *ifdefault(char *iface, size_t len)
return ifany(iface, len);
}

static void hton_packet(struct mping *packet)
{
packet->seq_no = htonl(packet->seq_no);

if (sizeof(packet->tv.tv_sec) == 8)
packet->tv.tv_sec = htonll(packet->tv.tv_sec);
else
packet->tv.tv_sec = htonl(packet->tv.tv_sec);

if (sizeof(packet->tv.tv_usec) == 8)
packet->tv.tv_usec = htonll(packet->tv.tv_usec);
else
packet->tv.tv_usec = htonl(packet->tv.tv_usec);
}

static void ntoh_packet(struct mping *packet)
{
packet->seq_no = ntohl(packet->seq_no);

if (sizeof(packet->tv.tv_sec) == 8)
packet->tv.tv_sec = ntohll(packet->tv.tv_sec);
else
packet->tv.tv_sec = ntohl(packet->tv.tv_sec);

if (sizeof(packet->tv.tv_usec) == 8)
packet->tv.tv_usec = ntohll(packet->tv.tv_usec);
else
packet->tv.tv_usec = ntohl(packet->tv.tv_usec);
}

/* Find IP address of default outbound LAN interface */
int ifinfo(char *iface, inet_addr_t *addr, int family)
{
Expand Down Expand Up @@ -526,10 +564,10 @@ void send_mping(int signo)
packet->ttl = arg_ttl;
packet->src_host = myaddr;
packet->dest_host = mcaddr;
packet->seq_no = htonl(seqno);
packet->seq_no = seqno;
packet->pid = pid;
packet->tv.tv_sec = htonl(packet->tv.tv_sec);
packet->tv.tv_usec = htonl(packet->tv.tv_usec);

ntoh_packet(packet);

send_packet(packet, sizeof(struct mping) + arg_payload);
seqno++;
Expand All @@ -547,9 +585,8 @@ int process_mping(char *packet, int len, unsigned char type)
}

rcvd_pkt = (struct mping *)packet;
rcvd_pkt->seq_no = ntohl(rcvd_pkt->seq_no);
rcvd_pkt->tv.tv_sec = ntohl(rcvd_pkt->tv.tv_sec);
rcvd_pkt->tv.tv_usec = ntohl(rcvd_pkt->tv.tv_usec);

ntoh_packet(rcvd_pkt);

if (strcmp(rcvd_pkt->version, VERSION)) {
dbg("Discarding packet: version mismatch (%s)", rcvd_pkt->version);
Expand Down Expand Up @@ -654,9 +691,8 @@ void receiver_listen_loop(void)
rcvd_pkt->type = RECEIVER;
rcvd_pkt->src_host = myaddr;
rcvd_pkt->dest_host = rcvd_pkt->src_host;
rcvd_pkt->seq_no = htonl(rcvd_pkt->seq_no);
rcvd_pkt->tv.tv_sec = htonl(rcvd_pkt->tv.tv_sec);
rcvd_pkt->tv.tv_usec = htonl(rcvd_pkt->tv.tv_usec);

hton_packet(rcvd_pkt);

/* send reply immediately */
send_packet(rcvd_pkt, len);
Expand Down Expand Up @@ -798,6 +834,11 @@ int main(int argc, char **argv)
if (ifindex <= 0)
exit(1);

if (debug) {
struct mping packet;
printf("tv_sec/tv_usec size: %zu/%zu\n", sizeof(packet.tv.tv_sec), sizeof(packet.tv.tv_usec));
}

init_socket(mcaddr.ss_family, ifindex);
myaddr = addr;

Expand Down