1.\" Copyright (c) 2020 Ryan Moeller <freqlabs@FreeBSD.org>
2.\"
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24.\" $FreeBSD$
25.\"
26.Dd September 29, 2022
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
41The function
42.Fn cap_getprotobyname
43is equivalent to
44.Xr getprotobyname 3
45except that the connection to the
46.Nm system.netdb
47service needs to be provided.
48.Sh EXAMPLES
49The following example first opens a capability to casper and then uses this
50capability to create the
51.Nm system.netdb
52casper service and uses it to look up a protocol by name.
53.Bd -literal
54cap_channel_t *capcas, *capnetdb;
55struct protoent *ent;
56
57/* Open capability to Casper. */
58capcas = cap_init();
59if (capcas == NULL)
60	err(1, "Unable to contact Casper");
61
62/* Enter capability mode sandbox. */
63if (caph_enter() < 0)
64	err(1, "Unable to enter capability mode");
65
66/* Use Casper capability to create capability to the system.netdb service. */
67capnetdb = cap_service_open(capcas, "system.netdb");
68if (capnetdb == NULL)
69	err(1, "Unable to open system.netdb service");
70
71/* Close Casper capability, we don't need it anymore. */
72cap_close(capcas);
73
74ent = cap_getprotobyname(capnetdb, "http");
75if (ent == NULL)
76       errx(1, "cap_getprotobyname failed to find http proto");
77.Ed
78.Sh SEE ALSO
79.Xr cap_enter 2 ,
80.Xr caph_enter 3 ,
81.Xr err 3 ,
82.Xr getprotobyname 3 ,
83.Xr capsicum 4 ,
84.Xr nv 9
85.Sh AUTHORS
86The
87.Nm cap_netdb
88service was implemented by
89.An Ryan Moeller Aq Mt freqlabs@FreeBSD.org .
90