/* Experimental SPF support.
Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004 - 2014
- License: GPL */
+ License: GPL
+ Copyright (c) The Exim Maintainers 2015 - 2018
+*/
/* Code for calling spf checks via libspf-alt. Called from acl.c. */
#include "exim.h"
-#ifdef EXPERIMENTAL_SPF
+#ifdef SUPPORT_SPF
/* must be kept in numeric order */
static spf_result_id spf_result_id_list[] = {
- { US"invalid", 0},
- { US"neutral", 1 },
- { US"pass", 2 },
- { US"fail", 3 },
- { US"softfail", 4 },
- { US"none", 5 },
- { US"err_temp", 6 }, /* Deprecated Apr 2014 */
- { US"err_perm", 7 }, /* Deprecated Apr 2014 */
- { US"temperror", 6 }, /* RFC 4408 defined */
- { US"permerror", 7 } /* RFC 4408 defined */
+ /* name value */
+ { US"invalid", 0},
+ { US"neutral", 1 },
+ { US"pass", 2 },
+ { US"fail", 3 },
+ { US"softfail", 4 },
+ { US"none", 5 },
+ { US"temperror", 6 }, /* RFC 4408 defined */
+ { US"permerror", 7 } /* RFC 4408 defined */
};
SPF_server_t *spf_server = NULL;
SPF_response_t *spf_response = NULL;
SPF_response_t *spf_response_2mx = NULL;
+
/* spf_init sets up a context that can be re-used for several
messages on the same SMTP connection (that come from the
- same host with the same HELO string) */
+ same host with the same HELO string)
-int spf_init(uschar *spf_helo_domain, uschar *spf_remote_addr) {
+Return: Boolean success */
- spf_server = SPF_server_new(SPF_DNS_CACHE, 0);
+BOOL
+spf_init(uschar *spf_helo_domain, uschar *spf_remote_addr)
+{
+spf_server = SPF_server_new(SPF_DNS_CACHE, 0);
- if ( spf_server == NULL ) {
- debug_printf("spf: SPF_server_new() failed.\n");
- return 0;
+if (!spf_server)
+ {
+ DEBUG(D_receive) debug_printf("spf: SPF_server_new() failed.\n");
+ return FALSE;
}
- if (SPF_server_set_rec_dom(spf_server, CS primary_hostname)) {
- debug_printf("spf: SPF_server_set_rec_dom(\"%s\") failed.\n", primary_hostname);
- spf_server = NULL;
- return 0;
+if (SPF_server_set_rec_dom(spf_server, CS primary_hostname))
+ {
+ DEBUG(D_receive) debug_printf("spf: SPF_server_set_rec_dom(\"%s\") failed.\n",
+ primary_hostname);
+ spf_server = NULL;
+ return FALSE;
}
- spf_request = SPF_request_new(spf_server);
-
- if (SPF_request_set_ipv4_str(spf_request, CS spf_remote_addr)
- && SPF_request_set_ipv6_str(spf_request, CS spf_remote_addr)) {
- debug_printf("spf: SPF_request_set_ipv4_str() and SPF_request_set_ipv6_str() failed [%s]\n", spf_remote_addr);
- spf_server = NULL;
- spf_request = NULL;
- return 0;
+spf_request = SPF_request_new(spf_server);
+
+if ( SPF_request_set_ipv4_str(spf_request, CS spf_remote_addr)
+ && SPF_request_set_ipv6_str(spf_request, CS spf_remote_addr)
+ )
+ {
+ DEBUG(D_receive)
+ debug_printf("spf: SPF_request_set_ipv4_str() and "
+ "SPF_request_set_ipv6_str() failed [%s]\n", spf_remote_addr);
+ spf_server = NULL;
+ spf_request = NULL;
+ return FALSE;
}
- if (SPF_request_set_helo_dom(spf_request, CS spf_helo_domain)) {
- debug_printf("spf: SPF_set_helo_dom(\"%s\") failed.\n", spf_helo_domain);
- spf_server = NULL;
- spf_request = NULL;
- return 0;
+if (SPF_request_set_helo_dom(spf_request, CS spf_helo_domain))
+ {
+ DEBUG(D_receive) debug_printf("spf: SPF_set_helo_dom(\"%s\") failed.\n",
+ spf_helo_domain);
+ spf_server = NULL;
+ spf_request = NULL;
+ return FALSE;
}
- return 1;
+return TRUE;
}
/* spf_process adds the envelope sender address to the existing
context (if any), retrieves the result, sets up expansion
- strings and evaluates the condition outcome. */
-
-int spf_process(uschar **listptr, uschar *spf_envelope_sender, int action) {
- int sep = 0;
- uschar *list = *listptr;
- uschar *spf_result_id;
- uschar spf_result_id_buffer[128];
- int rc = SPF_RESULT_PERMERROR;
-
- if (!(spf_server && spf_request)) {
- /* no global context, assume temp error and skip to evaluation */
- rc = SPF_RESULT_PERMERROR;
- goto SPF_EVALUATE;
- };
-
- if (SPF_request_set_env_from(spf_request, CS spf_envelope_sender)) {
- /* Invalid sender address. This should be a real rare occurence */
- rc = SPF_RESULT_PERMERROR;
- goto SPF_EVALUATE;
- }
+ strings and evaluates the condition outcome.
+
+Return: OK/FAIL */
+
+int
+spf_process(const uschar **listptr, uschar *spf_envelope_sender, int action)
+{
+int sep = 0;
+const uschar *list = *listptr;
+uschar *spf_result_id;
+int rc = SPF_RESULT_PERMERROR;
+
+if (!(spf_server && spf_request))
+ /* no global context, assume temp error and skip to evaluation */
+ rc = SPF_RESULT_PERMERROR;
+else if (SPF_request_set_env_from(spf_request, CS spf_envelope_sender))
+ /* Invalid sender address. This should be a real rare occurrence */
+ rc = SPF_RESULT_PERMERROR;
+
+else
+ {
/* get SPF result */
if (action == SPF_PROCESS_FALLBACK)
+ {
SPF_request_query_fallback(spf_request, &spf_response, CS spf_guess);
+ spf_result_guessed = TRUE;
+ }
else
SPF_request_query_mailfrom(spf_request, &spf_response);
/* set up expansion items */
- spf_header_comment = (uschar *)SPF_response_get_header_comment(spf_response);
- spf_received = (uschar *)SPF_response_get_received_spf(spf_response);
- spf_result = (uschar *)SPF_strresult(SPF_response_result(spf_response));
- spf_smtp_comment = (uschar *)SPF_response_get_smtp_comment(spf_response);
+ spf_header_comment = US SPF_response_get_header_comment(spf_response);
+ spf_received = US SPF_response_get_received_spf(spf_response);
+ spf_result = US SPF_strresult(SPF_response_result(spf_response));
+ spf_smtp_comment = US SPF_response_get_smtp_comment(spf_response);
rc = SPF_response_result(spf_response);
+ }
+
+/* We got a result. Now see if we should return OK or FAIL for it */
+DEBUG(D_acl) debug_printf("SPF result is %s (%d)\n", SPF_strresult(rc), rc);
+
+if (action == SPF_PROCESS_GUESS && (!strcmp (SPF_strresult(rc), "none")))
+ return spf_process(listptr, spf_envelope_sender, SPF_PROCESS_FALLBACK);
+
+while ((spf_result_id = string_nextinlist(&list, &sep, NULL, 0)))
+ {
+ BOOL negate, result;
- /* We got a result. Now see if we should return OK or FAIL for it */
- SPF_EVALUATE:
- debug_printf("SPF result is %s (%d)\n", SPF_strresult(rc), rc);
-
- if (action == SPF_PROCESS_GUESS && (!strcmp (SPF_strresult(rc), "none")))
- return spf_process(listptr, spf_envelope_sender, SPF_PROCESS_FALLBACK);
-
- while ((spf_result_id = string_nextinlist(&list, &sep,
- spf_result_id_buffer,
- sizeof(spf_result_id_buffer))) != NULL) {
- int negate = 0;
- int result = 0;
-
- /* Check for negation */
- if (spf_result_id[0] == '!') {
- negate = 1;
- spf_result_id++;
- };
-
- /* Check the result identifier */
- result = Ustrcmp(spf_result_id, spf_result_id_list[rc].name);
- if (!negate && result==0) return OK;
- if (negate && result!=0) return OK;
- };
-
- /* no match */
- return FAIL;
+ if ((negate = spf_result_id[0] == '!'))
+ spf_result_id++;
+
+ result = Ustrcmp(spf_result_id, spf_result_id_list[rc].name) == 0;
+ if (negate != result) return OK;
+ }
+
+/* no match */
+return FAIL;
+}
+
+
+
+gstring *
+authres_spf(gstring * g)
+{
+uschar * s;
+if (!spf_result) return g;
+
+g = string_append(g, 2, US";\n\tspf=", spf_result);
+if (spf_result_guessed)
+ g = string_cat(g, US" (best guess record for domain)");
+
+s = expand_string(US"$sender_address_domain");
+return s && *s
+ ? string_append(g, 2, US" smtp.mailfrom=", s)
+ : string_cat(g, US" smtp.mailfrom=<>");
}
+
#endif