xref: /freebsd/lib/libcasper/services/cap_netdb/cap_netdb.c (revision 7ef62cebc2f965b0f640263e179276928885e33d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020 Ryan Moeller <freqlabs@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/dnv.h>
32 #include <sys/nv.h>
33 #include <netinet/in.h>
34 
35 #include <assert.h>
36 #include <errno.h>
37 #include <netdb.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 
42 #include <libcasper.h>
43 #include <libcasper_service.h>
44 
45 #include "cap_netdb.h"
46 
47 static struct protoent *
48 protoent_unpack(nvlist_t *nvl)
49 {
50 	struct protoent *pp;
51 	char **aliases;
52 	size_t n;
53 
54 	pp = malloc(sizeof(*pp));
55 	if (pp == NULL) {
56 		nvlist_destroy(nvl);
57 		return (NULL);
58 	}
59 
60 	pp->p_name = nvlist_take_string(nvl, "name");
61 
62 	aliases = nvlist_take_string_array(nvl, "aliases", &n);
63 	pp->p_aliases = realloc(aliases, sizeof(char *) * (n + 1));
64 	if (pp->p_aliases == NULL) {
65 		while (n-- > 0)
66 			free(aliases[n]);
67 		free(aliases);
68 		free(pp->p_name);
69 		free(pp);
70 		nvlist_destroy(nvl);
71 		return (NULL);
72 	}
73 	pp->p_aliases[n] = NULL;
74 
75 	pp->p_proto = (int)nvlist_take_number(nvl, "proto");
76 
77 	nvlist_destroy(nvl);
78 	return (pp);
79 }
80 
81 struct protoent *
82 cap_getprotobyname(cap_channel_t *chan, const char *name)
83 {
84 	nvlist_t *nvl;
85 
86 	nvl = nvlist_create(0);
87 	nvlist_add_string(nvl, "cmd", "getprotobyname");
88 	nvlist_add_string(nvl, "name", name);
89 	nvl = cap_xfer_nvlist(chan, nvl);
90 	if (nvl == NULL)
91 		return (NULL);
92 	if (dnvlist_get_number(nvl, "error", 0) != 0) {
93 		nvlist_destroy(nvl);
94 		return (NULL);
95 	}
96 	return (protoent_unpack(nvl));
97 }
98 
99 static void
100 protoent_pack(const struct protoent *pp, nvlist_t *nvl)
101 {
102 	int n = 0;
103 
104 	nvlist_add_string(nvl, "name", pp->p_name);
105 
106 	while (pp->p_aliases[n] != NULL)
107 		++n;
108 	nvlist_add_string_array(nvl, "aliases",
109 	    (const char * const *)pp->p_aliases, n);
110 
111 	nvlist_add_number(nvl, "proto", (uint64_t)pp->p_proto);
112 }
113 
114 static int
115 netdb_getprotobyname(const nvlist_t *limits __unused, const nvlist_t *nvlin,
116     nvlist_t *nvlout)
117 {
118 	const char *name;
119 	struct protoent *pp;
120 
121 	name = dnvlist_get_string(nvlin, "name", NULL);
122 	if (name == NULL)
123 		return (EDOOFUS);
124 
125 	pp = getprotobyname(name);
126 	if (pp == NULL)
127 		return (EINVAL);
128 
129 	protoent_pack(pp, nvlout);
130 	return (0);
131 }
132 
133 static int
134 netdb_limit(const nvlist_t *oldlimits __unused,
135     const nvlist_t *newlimits __unused)
136 {
137 
138 	return (0);
139 }
140 
141 static int
142 netdb_command(const char *cmd, const nvlist_t *limits, nvlist_t *nvlin,
143     nvlist_t *nvlout)
144 {
145 	int error;
146 
147 	if (strcmp(cmd, "getprotobyname") == 0)
148 		error = netdb_getprotobyname(limits, nvlin, nvlout);
149 	else
150 		error = NO_RECOVERY;
151 
152 	return (error);
153 }
154 
155 CREATE_SERVICE("system.netdb", netdb_limit, netdb_command, 0);
156