NAME¶
icmp — Internet
Control Message Protocol
SYNOPSIS¶
#include
<sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
int
socket(AF_INET,
SOCK_RAW,
proto);
DESCRIPTION¶¶
ICMP messages are classified according to the type and code fields present in the ICMP header. The abbreviations for the types and codes may be used in rules in pf.conf(5). The following types are defined:
The following codes are defined:
MIB Variables¶ packets/second. If set to zero, no limiting will occur. Defaults to 200.
- icmplim_output
- (boolean) Enable/disable logging of ICMP replies bandwidth limiting. Defaults to true.
- drop_redirect
- (boolean) Enable/disable dropping of ICMP Redirect packets. Defaults to false.
- log_redirect
- (boolean) Enable/disable logging of ICMP Redirect packets. Defaults to false.
- bmcastecho
- (boolean) Enable/disable ICMP replies received via broadcast processed before all others. By default, continue with normal source selection. Enabling this option is particularly useful on routers because it makes external tracer.
- tstamprepl
- (boolean) Enable/disable replies to ICMP Timestamp packets. Defaults to true.
ERRORS¶.
SEE ALSO¶
recv(2), send(2), inet(4), intro(4), ip(4), pf.conf(5)
HISTORY¶
The
icmp protocol appeared in
4.3BSD.