xref: /freebsd/contrib/sendmail/libmilter/sm_gethost.c (revision 2fb4f839f3fc72ce2bab12f9ba4760f97f73e97f)
1 /*
2  *  Copyright (c) 1999-2001, 2004, 2010, 2013 Proofpoint, Inc. and its suppliers.
3  *	All rights reserved.
4  *
5  * By using this file, you agree to the terms and conditions set
6  * forth in the LICENSE file which can be found at the top level of
7  * the sendmail distribution.
8  *
9  */
10 
11 #include <sm/gen.h>
12 SM_RCSID("@(#)$Id: sm_gethost.c,v 8.32 2013-11-22 20:51:36 ca Exp $")
13 
14 #include <sendmail.h>
15 #if NETINET || NETINET6
16 # include <arpa/inet.h>
17 #endif
18 #include "libmilter.h"
19 
20 /*
21 **  MI_GETHOSTBY{NAME,ADDR} -- compatibility routines for gethostbyXXX
22 **
23 **	Some operating systems have weird problems with the gethostbyXXX
24 **	routines.  For example, Solaris versions at least through 2.3
25 **	don't properly deliver a canonical h_name field.  This tries to
26 **	work around these problems.
27 **
28 **	Support IPv6 as well as IPv4.
29 */
30 
31 #if NETINET6 && NEEDSGETIPNODE
32 
33 static struct hostent *sm_getipnodebyname __P((const char *, int, int, int *));
34 
35 # ifndef AI_ADDRCONFIG
36 #  define AI_ADDRCONFIG	0	/* dummy */
37 # endif
38 # ifndef AI_ALL
39 #  define AI_ALL	0	/* dummy */
40 # endif
41 # ifndef AI_DEFAULT
42 #  define AI_DEFAULT	0	/* dummy */
43 # endif
44 
45 static struct hostent *
sm_getipnodebyname(name,family,flags,err)46 sm_getipnodebyname(name, family, flags, err)
47 	const char *name;
48 	int family;
49 	int flags;
50 	int *err;
51 {
52 	struct hostent *h;
53 # if HAS_GETHOSTBYNAME2
54 
55 	h = gethostbyname2(name, family);
56 	if (h == NULL)
57 		*err = h_errno;
58 	return h;
59 
60 # else /* HAS_GETHOSTBYNAME2 */
61 #  ifdef RES_USE_INET6
62 	bool resv6 = true;
63 
64 	if (family == AF_INET6)
65 	{
66 		/* From RFC2133, section 6.1 */
67 		resv6 = bitset(RES_USE_INET6, _res.options);
68 		_res.options |= RES_USE_INET6;
69 	}
70 #  endif /* RES_USE_INET6 */
71 	SM_SET_H_ERRNO(0);
72 	h = gethostbyname(name);
73 #  ifdef RES_USE_INET6
74 	if (!resv6)
75 		_res.options &= ~RES_USE_INET6;
76 #  endif
77 
78 	/* the function is supposed to return only the requested family */
79 	if (h != NULL && h->h_addrtype != family)
80 	{
81 #  if NETINET6
82 		freehostent(h);
83 #  endif
84 		h = NULL;
85 		*err = NO_DATA;
86 	}
87 	else
88 		*err = h_errno;
89 	return h;
90 # endif /* HAS_GETHOSTBYNAME2 */
91 }
92 
93 void
freehostent(h)94 freehostent(h)
95 	struct hostent *h;
96 {
97 	/*
98 	**  Stub routine -- if they don't have getipnodeby*(),
99 	**  they probably don't have the free routine either.
100 	*/
101 
102 	return;
103 }
104 #else /* NEEDSGETIPNODE && NETINET6 */
105 #define sm_getipnodebyname getipnodebyname
106 #endif /* NEEDSGETIPNODE && NETINET6 */
107 
108 struct hostent *
mi_gethostbyname(name,family)109 mi_gethostbyname(name, family)
110 	char *name;
111 	int family;
112 {
113 	struct hostent *h = NULL;
114 #if (SOLARIS > 10000 && SOLARIS < 20400) || (defined(SOLARIS) && SOLARIS < 204) || (defined(sony_news) && defined(__svr4))
115 # if SOLARIS == 20300 || SOLARIS == 203
116 	static struct hostent hp;
117 	static char buf[1000];
118 	extern struct hostent *_switch_gethostbyname_r();
119 
120 	h = _switch_gethostbyname_r(name, &hp, buf, sizeof(buf), &h_errno);
121 # else /* SOLARIS == 20300 || SOLARIS == 203 */
122 	extern struct hostent *__switch_gethostbyname();
123 
124 	h = __switch_gethostbyname(name);
125 # endif /* SOLARIS == 20300 || SOLARIS == 203 */
126 #else /* (SOLARIS > 10000 && SOLARIS < 20400) || (defined(SOLARIS) && SOLARIS < 204) || (defined(sony_news) && defined(__svr4)) */
127 # if NETINET6
128 #  ifndef SM_IPNODEBYNAME_FLAGS
129     /* For IPv4-mapped addresses, use: AI_DEFAULT|AI_ALL */
130 #   define SM_IPNODEBYNAME_FLAGS	AI_ADDRCONFIG
131 #  endif
132 
133 	int flags = SM_IPNODEBYNAME_FLAGS;
134 	int err;
135 # endif /* NETINET6 */
136 
137 # if NETINET6
138 #  if ADDRCONFIG_IS_BROKEN
139 	flags &= ~AI_ADDRCONFIG;
140 #  endif
141 	h = sm_getipnodebyname(name, family, flags, &err);
142 	SM_SET_H_ERRNO(err);
143 # else /* NETINET6 */
144 	h = gethostbyname(name);
145 # endif /* NETINET6 */
146 
147 #endif /* (SOLARIS > 10000 && SOLARIS < 20400) || (defined(SOLARIS) && SOLARIS < 204) || (defined(sony_news) && defined(__svr4)) */
148 
149 	/* the function is supposed to return only the requested family */
150 	if (h != NULL && h->h_addrtype != family)
151 	{
152 #if NETINET6
153 		freehostent(h);
154 #endif
155 		h = NULL;
156 		SM_SET_H_ERRNO(NO_DATA);
157 	}
158 	return h;
159 }
160 
161 #if NETINET6
162 /*
163 **  MI_INET_PTON -- convert printed form to network address.
164 **
165 **	Wrapper for inet_pton() which handles IPv6: labels.
166 **
167 **	Parameters:
168 **		family -- address family
169 **		src -- string
170 **		dst -- destination address structure
171 **
172 **	Returns:
173 **		1 if the address was valid
174 **		0 if the address wasn't parsable
175 **		-1 if error
176 */
177 
178 int
mi_inet_pton(family,src,dst)179 mi_inet_pton(family, src, dst)
180 	int family;
181 	const char *src;
182 	void *dst;
183 {
184 	if (family == AF_INET6 &&
185 	    strncasecmp(src, "IPv6:", 5) == 0)
186 		src += 5;
187 	return inet_pton(family, src, dst);
188 }
189 #endif /* NETINET6 */
190