1 /*************************************************
2 *     Exim - an Internet mail transport agent    *
3 *************************************************/
4 
5 /* Exim - SPF lookup module using libspf2
6    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7 
8 Copyright (c) 2005 Chris Webb, Arachsys Internet Services Ltd
9 
10 This program is free software; you can redistribute it and/or
11 modify it under the terms of the GNU General Public License
12 as published by the Free Software Foundation; either version 2
13 of the License, or (at your option) any later version.
14 
15 Copyright (c) The Exim Maintainers 2020
16 */
17 
18 #include "../exim.h"
19 
20 #ifndef SUPPORT_SPF
21 static void dummy(int x);
dummy2(int x)22 static void dummy2(int x) { dummy(x-1); }
dummy(int x)23 static void dummy(int x) { dummy2(x-1); }
24 #else
25 
26 #include "lf_functions.h"
27 #if !defined(HAVE_NS_TYPE) && defined(NS_INADDRSZ)
28 # define HAVE_NS_TYPE
29 #endif
30 #include <spf2/spf.h>
31 #include <spf2/spf_dns_resolv.h>
32 #include <spf2/spf_dns_cache.h>
33 
34 extern SPF_dns_server_t * SPF_dns_exim_new(int);
35 
36 
37 static void *
spf_open(const uschar * filename,uschar ** errmsg)38 spf_open(const uschar * filename, uschar ** errmsg)
39 {
40 SPF_dns_server_t * dc;
41 SPF_server_t *spf_server = NULL;
42 int debug = 0;
43 
44 DEBUG(D_lookup) debug = 1;
45 
46 if ((dc = SPF_dns_exim_new(debug)))
47   if ((dc = SPF_dns_cache_new(dc, NULL, debug, 8)))
48     spf_server = SPF_server_new_dns(dc, debug);
49 
50 if (!spf_server)
51   {
52   *errmsg = US"SPF_dns_exim_nnew() failed";
53   return NULL;
54   }
55 return (void *) spf_server;
56 }
57 
58 
59 static void
spf_close(void * handle)60 spf_close(void *handle)
61 {
62 SPF_server_t *spf_server = handle;
63 if (spf_server) SPF_server_free(spf_server);
64 }
65 
66 static int
spf_find(void * handle,const uschar * filename,const uschar * keystring,int key_len,uschar ** result,uschar ** errmsg,uint * do_cache,const uschar * opts)67 spf_find(void * handle, const uschar * filename, const uschar * keystring,
68   int key_len, uschar ** result, uschar ** errmsg, uint * do_cache,
69   const uschar * opts)
70 {
71 SPF_server_t *spf_server = handle;
72 SPF_request_t *spf_request;
73 SPF_response_t *spf_response = NULL;
74 
75 if (!(spf_request = SPF_request_new(spf_server)))
76   {
77   *errmsg = US"SPF_request_new() failed";
78   return FAIL;
79   }
80 
81 #if HAVE_IPV6
82 switch (string_is_ip_address(filename, NULL))
83 #else
84 switch (4)
85 #endif
86   {
87   case 4:
88     if (!SPF_request_set_ipv4_str(spf_request, CS filename))
89       break;
90     *errmsg = string_sprintf("invalid IPv4 address '%s'", filename);
91     return FAIL;
92 #if HAVE_IPV6
93 
94   case 6:
95     if (!SPF_request_set_ipv6_str(spf_request, CS filename))
96       break;
97     *errmsg = string_sprintf("invalid IPv6 address '%s'", filename);
98     return FAIL;
99 
100   default:
101     *errmsg = string_sprintf("invalid IP address '%s'", filename);
102     return FAIL;
103 #endif
104   }
105 
106 if (SPF_request_set_env_from(spf_request, CS keystring))
107     {
108   *errmsg = string_sprintf("invalid envelope from address '%s'", keystring);
109   return FAIL;
110 }
111 
112 SPF_request_query_mailfrom(spf_request, &spf_response);
113 *result = string_copy(US SPF_strresult(SPF_response_result(spf_response)));
114 
115 DEBUG(D_lookup) spf_response_debug(spf_response);
116 
117 SPF_response_free(spf_response);
118 SPF_request_free(spf_request);
119 return OK;
120 }
121 
122 
123 /*************************************************
124 *         Version reporting entry point          *
125 *************************************************/
126 
127 /* See local README for interface description. */
128 
129 #include "../version.h"
130 
131 void
spf_version_report(FILE * f)132 spf_version_report(FILE *f)
133 {
134 #ifdef DYNLOOKUP
135 fprintf(f, "Library version: SPF: Exim version %s\n", EXIM_VERSION_STR);
136 #endif
137 }
138 
139 
140 static lookup_info _lookup_info = {
141   .name = US"spf",			/* lookup name */
142   .type = 0,				/* not absfile, not query style */
143   .open = spf_open,			/* open function */
144   .check = NULL,			/* no check function */
145   .find = spf_find,			/* find function */
146   .close = spf_close,			/* close function */
147   .tidy = NULL,				/* no tidy function */
148   .quote = NULL,			/* no quoting function */
149   .version_report = spf_version_report             /* version reporting */
150 };
151 
152 #ifdef DYNLOOKUP
153 #define spf_lookup_module_info _lookup_module_info
154 #endif
155 
156 static lookup_info *_lookup_list[] = { &_lookup_info };
157 lookup_module_info spf_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
158 
159 #endif /* SUPPORT_SPF */
160