6fd7445615ceb95a86087bbcceb1640dc860bfeb
[exim.git] / src / src / spf.c
1 /* $Cambridge: exim/src/src/spf.c,v 1.4 2005/05/24 08:15:02 tom Exp $ */
2
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
6
7 /* Experimental SPF support.
8 Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004
9 License: GPL */
10
11 /* Code for calling spf checks via libspf-alt. Called from acl.c. */
12
13 #include "exim.h"
14 #ifdef EXPERIMENTAL_SPF
15
16 SPF_server_t *spf_server = NULL;
17 SPF_request_t *spf_request = NULL;
18 SPF_response_t *spf_response = NULL;
19 SPF_response_t *spf_response_2mx = NULL;
20
21 /* spf_init sets up a context that can be re-used for several
22 messages on the same SMTP connection (that come from the
23 same host with the same HELO string) */
24
25 int spf_init(uschar *spf_helo_domain, uschar *spf_remote_addr) {
26 uschar *p;
27
28 spf_server = SPF_server_new(SPF_DNS_CACHE, 1);
29
30 if ( spf_server == NULL ) {
31 debug_printf("spf: SPF_server_new() failed.\n");
32 return 0;
33 }
34
35 spf_request = SPF_request_new(spf_server);
36
37 if (SPF_request_set_ipv4_str(spf_request, spf_remote_addr)) {
38 debug_printf("spf: SPF_request_set_ipv4_str() failed.\n");
39 spf_server = NULL;
40 spf_request = NULL;
41 return 0;
42 }
43
44 if (SPF_request_set_helo_dom(spf_request, spf_helo_domain)) {
45 debug_printf("spf: SPF_set_helo_dom() failed.\n");
46 spf_server = NULL;
47 spf_request = NULL;
48 return 0;
49 }
50
51 return 1;
52 }
53
54
55 /* spf_process adds the envelope sender address to the existing
56 context (if any), retrieves the result, sets up expansion
57 strings and evaluates the condition outcome. */
58
59 int spf_process(uschar **listptr, uschar *spf_envelope_sender) {
60 int sep = 0;
61 uschar *list = *listptr;
62 uschar *spf_result_id;
63 uschar spf_result_id_buffer[128];
64 int rc = SPF_RESULT_PERMERROR;
65
66 if (!(spf_server && spf_request)) {
67 /* no global context, assume temp error and skip to evaluation */
68 rc = SPF_RESULT_PERMERROR;
69 goto SPF_EVALUATE;
70 };
71
72 if (SPF_request_set_env_from(spf_request, spf_envelope_sender)) {
73 /* Invalid sender address. This should be a real rare occurence */
74 rc = SPF_RESULT_PERMERROR;
75 goto SPF_EVALUATE;
76 }
77
78 /* get SPF result */
79 SPF_request_query_mailfrom(spf_request, &spf_response);
80
81 /* set up expansion items */
82 spf_header_comment = (uschar *)SPF_response_get_header_comment(spf_response);
83 spf_received = (uschar *)SPF_response_get_received_spf(spf_response);
84 spf_result = (uschar *)SPF_strresult(SPF_response_result(spf_response));
85 spf_smtp_comment = (uschar *)SPF_response_get_smtp_comment(spf_response);
86
87 rc = SPF_response_result(spf_response);
88
89 /* We got a result. Now see if we should return OK or FAIL for it */
90 SPF_EVALUATE:
91 debug_printf("SPF result is %s (%d)\n", SPF_strresult(rc), rc);
92 while ((spf_result_id = string_nextinlist(&list, &sep,
93 spf_result_id_buffer,
94 sizeof(spf_result_id_buffer))) != NULL) {
95 int negate = 0;
96 int result = 0;
97
98 /* Check for negation */
99 if (spf_result_id[0] == '!') {
100 negate = 1;
101 spf_result_id++;
102 };
103
104 /* Check the result identifier */
105 result = Ustrcmp(spf_result_id, spf_result_id_list[rc].name);
106 if (!negate && result==0) return OK;
107 if (negate && result!=0) return OK;
108 };
109
110 /* no match */
111 return FAIL;
112 }
113
114 #endif
115