1.\" Copyright (c) 2020 Ryan Moeller <freqlabs@FreeBSD.org>
2.\"
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24.\" $FreeBSD$
25.\"
26.Dd May 12, 2020
27.Dt CAP_NETDB 3
28.Os
29.Sh NAME
30.Nm cap_getprotobyname ,
31.Nd "library for getting network proto entry in capability mode"
32.Sh LIBRARY
33.Lb libcap_netdb
34.Sh SYNOPSIS
35.In sys/nv.h
36.In libcasper.h
37.In casper/cap_netdb.h
38.Ft "struct protoent *"
39.Fn cap_getprotobyname "const cap_channel_t *chan" "const char *name"
40.Sh DESCRIPTION
41.Bf -symbolic
42The function
43.Fn cap_getprotobyname
44is equivalent to
45.Xr getprotobyname 3
46except that the connection to the
47.Nm system.netdb
48service needs to be provided.
49.Sh EXAMPLES
50The following example first opens a capability to casper and then uses this
51capability to create the
52.Nm system.netdb
53casper service and uses it to look up a protocol by name.
54.Bd -literal
55cap_channel_t *capcas, *capnetdb;
56struct protoent *ent;
57
58/* Open capability to Casper. */
59capcas = cap_init();
60if (capcas == NULL)
61	err(1, "Unable to contact Casper");
62
63/* Enter capability mode sandbox. */
64if (caph_enter() < 0)
65	err(1, "Unable to enter capability mode");
66
67/* Use Casper capability to create capability to the system.netdb service. */
68capnetdb = cap_service_open(capcas, "system.netdb");
69if (capnetdb == NULL)
70	err(1, "Unable to open system.netdb service");
71
72/* Close Casper capability, we don't need it anymore. */
73cap_close(capcas);
74
75ent = cap_getprotobyname(capnetdb, "http");
76if (ent == NULL)
77       errx(1, "cap_getprotobyname failed to find http proto");
78.Ed
79.Sh SEE ALSO
80.Xr cap_enter 2 ,
81.Xr caph_enter 3 ,
82.Xr err 3 ,
83.Xr getprotobyname 3 ,
84.Xr capsicum 4 ,
85.Xr nv 9
86.Sh AUTHORS
87The
88.Nm cap_netdb
89service was implemented by
90.An Ryan Moeller Aq Mt freqlabs@FreeBSD.org .
91