src/liboping.c: Replace sizeof(struct icmphdr) with ICMP_MINLEN.

The definitions of struct icmphdr differ between platforms, while
ICMP_MINLEN is always 8, which is what we need here.

diff --git a/src/liboping.c b/src/liboping.c
index 396f489..f3c850e 100644 (file)
--- a/src/liboping.c
+++ b/src/liboping.c
@@ -298,12 +298,12 @@ static pinghost_t *ping_receive_ipv4 (pingobj_t *obj, char *buffer,
        buffer     += ip_hdr_len;
        buffer_len -= ip_hdr_len;
 
-       if (buffer_len < sizeof (struct icmphdr))
+       if (buffer_len < ICMP_MINLEN)
                return (NULL);
 
        icmp_hdr = (struct icmp *) buffer;
-       buffer     += sizeof (struct icmphdr);
-       buffer_len -= sizeof (struct icmphdr);
+       buffer     += ICMP_MINLEN;
+       buffer_len -= ICMP_MINLEN;
 
        if (icmp_hdr->icmp_type != ICMP_ECHOREPLY)
        {
@@ -314,7 +314,7 @@ static pinghost_t *ping_receive_ipv4 (pingobj_t *obj, char *buffer,
        recv_checksum = icmp_hdr->icmp_cksum;
        icmp_hdr->icmp_cksum = 0;
        calc_checksum = ping_icmp4_checksum ((char *) icmp_hdr,
-                       sizeof (struct icmphdr) + buffer_len);
+                       ICMP_MINLEN + buffer_len);
 
        if (recv_checksum != calc_checksum)
        {
@@ -392,12 +392,12 @@ static pinghost_t *ping_receive_ipv6 (pingobj_t *obj, char *buffer,
 
        pinghost_t *ptr;
 
-       if (buffer_len < sizeof (struct icmp6_hdr))
+       if (buffer_len < ICMP_MINLEN)
                return (NULL);
 
        icmp_hdr = (struct icmp6_hdr *) buffer;
-       buffer     += sizeof (struct icmp);
-       buffer_len -= sizeof (struct icmp);
+       buffer     += ICMP_MINLEN;
+       buffer_len -= ICMP_MINLEN;
 
        if (icmp_hdr->icmp6_type != ICMP6_ECHO_REPLY)
        {
@@ -825,7 +825,7 @@ static int ping_send_one_ipv4 (pingobj_t *obj, pinghost_t *ph)
 
        memset (buf, '\0', sizeof (buf));
        icmp4 = (struct icmp *) buf;
-       data  = buf + sizeof (struct icmphdr);
+       data  = buf + ICMP_MINLEN;
 
        icmp4->icmp_type  = ICMP_ECHO;
        icmp4->icmp_code  = 0;
@@ -833,11 +833,11 @@ static int ping_send_one_ipv4 (pingobj_t *obj, pinghost_t *ph)
        icmp4->icmp_id    = htons (ph->ident);
        icmp4->icmp_seq   = htons (ph->sequence);
 
-       buflen = sizeof(buf) - sizeof (struct icmphdr);
+       buflen = sizeof(buf) - ICMP_MINLEN;
        strncpy (data, ph->data, buflen);
        datalen = strlen (data);
 
-       buflen = datalen + sizeof (struct icmphdr);
+       buflen = datalen + ICMP_MINLEN;
 
        icmp4->icmp_cksum = ping_icmp4_checksum (buf, buflen);
 
@@ -880,11 +880,11 @@ static int ping_send_one_ipv6 (pingobj_t *obj, pinghost_t *ph)
        icmp6->icmp6_id    = htons (ph->ident);
        icmp6->icmp6_seq   = htons (ph->sequence);
 
-       buflen = 4096 - sizeof (struct icmp6_hdr);
+       buflen = 4096 - ICMP_MINLEN;
        strncpy (data, ph->data, buflen);
        datalen = strlen (data);
 
-       buflen = datalen + sizeof (struct icmp6_hdr);
+       buflen = datalen + ICMP_MINLEN;
 
        dprintf ("Sending ICMPv6 package with ID 0x%04x\n", ph->ident);