CAP_NETDB(3) FreeBSD Library Functions Manual CAP_NETDB(3)
NAME
cap_getprotobyname, - library for getting network proto entry in
capability mode
LIBRARY
library "libcap_netdb"
SYNOPSIS
#include <sys/nv.h>
#include <libcasper.h>
#include <casper/cap_netdb.h>
struct protoent *
cap_getprotobyname(const cap_channel_t *chan, const char *name);
DESCRIPTION
The function cap_getprotobyname() is equivalent to getprotobyname(3)
except that the connection to the system.netdb service needs to be
provided. It is reentrant but not thread-safe. That is, it may be
called from separate threads only with different cap_channel_t arguments
or with synchronization.
EXAMPLES
The following example first opens a capability to casper and then uses
this capability to create the system.netdb casper service and uses it to
look up a protocol by name.
cap_channel_t *capcas, *capnetdb;
struct protoent *ent;
/* Open capability to Casper. */
capcas = cap_init();
if (capcas == NULL)
err(1, "Unable to contact Casper");
/* Enter capability mode sandbox. */
if (caph_enter() < 0)
err(1, "Unable to enter capability mode");
/* Use Casper capability to create capability to the system.netdb service. */
capnetdb = cap_service_open(capcas, "system.netdb");
if (capnetdb == NULL)
err(1, "Unable to open system.netdb service");
/* Close Casper capability, we don't need it anymore. */
cap_close(capcas);
ent = cap_getprotobyname(capnetdb, "http");
if (ent == NULL)
errx(1, "cap_getprotobyname failed to find http proto");
SEE ALSO
cap_enter(2), caph_enter(3), err(3), getprotobyname(3), capsicum(4),
nv(9)
AUTHORS
The cap_netdb service was implemented by Ryan Moeller
<
[email protected]>.
FreeBSD 14.1-RELEASE-p8 December 6, 2023 FreeBSD 14.1-RELEASE-p8