LDAP: Check for errors of TLS initialisation

[exim.git] / src / src / lookups / ldap.c

diff --git a/src/src/lookups/ldap.c b/src/src/lookups/ldap.c
index c41b9212806762d8a77807fb5d19bdce2c26fd4f..5c1ea0b569f22fd9630a08490c11ee777c18ae93 100644 (file)
--- a/src/src/lookups/ldap.c
+++ b/src/src/lookups/ldap.c
@@ -1,10 +1,8 @@
-/* $Cambridge: exim/src/src/lookups/ldap.c,v 1.9 2005/02/17 11:58:27 ph10 Exp $ */
-

 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2005 */
+/* Copyright (c) University of Cambridge 1995 - 2009 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Many thanks to Stuart Lynne for contributing the original code for this
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Many thanks to Stuart Lynne for contributing the original code for this


@@ -15,23 +13,14 @@ researching how to handle the different kinds of error. */
 
 #include "../exim.h"
 #include "lf_functions.h"
 
 #include "../exim.h"
 #include "lf_functions.h"

-#include "ldap.h"
-

 
 

-/* We can't just compile this code and allow the library mechanism to omit the
-functions if they are not wanted, because we need to have the LDAP headers
-available for compiling. Therefore, compile these functions only if LOOKUP_LDAP
-is defined. However, some compilers don't like compiling empty modules, so keep
-them happy with a dummy when skipping the rest. Make it reference itself to
-stop picky compilers complaining that it is unused, and put in a dummy argument
-to stop even pickier compilers complaining about infinite loops. */

 
 

-#ifndef LOOKUP_LDAP
-static void dummy(int x) { dummy(x-1); }
-#else
+/* Include LDAP headers. The code below uses some "old" LDAP interfaces that
+are deprecated in OpenLDAP. I don't know their status in other LDAP
+implementations. LDAP_DEPRECATED causes their prototypes to be defined in
+ldap.h. */

 
 

-
-/* Include LDAP headers */
+#define LDAP_DEPRECATED 1

 
 #include <lber.h>
 #include <ldap.h>
 
 #include <lber.h>
 #include <ldap.h>


@@ -132,6 +121,7 @@ Arguments:
   tcplimit      max time for network activity, e.g. connect, or 0 for OS default
   deference     the dereference option, which is one of
                   LDAP_DEREF_{NEVER,SEARCHING,FINDING,ALWAYS}
   tcplimit      max time for network activity, e.g. connect, or 0 for OS default
   deference     the dereference option, which is one of
                   LDAP_DEREF_{NEVER,SEARCHING,FINDING,ALWAYS}

+  referrals     the referral option, which is LDAP_OPT_ON or LDAP_OPT_OFF

 
 Returns:        OK or FAIL or DEFER
                 FAIL is given only if a lookup was performed successfully, but
 
 Returns:        OK or FAIL or DEFER
                 FAIL is given only if a lookup was performed successfully, but


@@ -141,7 +131,7 @@ Returns:        OK or FAIL or DEFER
 static int
 perform_ldap_search(uschar *ldap_url, uschar *server, int s_port, int search_type,
   uschar **res, uschar **errmsg, BOOL *defer_break, uschar *user, uschar *password,
 static int
 perform_ldap_search(uschar *ldap_url, uschar *server, int s_port, int search_type,
   uschar **res, uschar **errmsg, BOOL *defer_break, uschar *user, uschar *password,

-  int sizelimit, int timelimit, int tcplimit, int dereference)
+  int sizelimit, int timelimit, int tcplimit, int dereference, void *referrals)

 {
 LDAPURLDesc     *ludp = NULL;
 LDAPMessage     *result = NULL;
 {
 LDAPURLDesc     *ludp = NULL;
 LDAPMessage     *result = NULL;


@@ -439,6 +429,60 @@ if (lcp == NULL)
     }
   #endif  /* LDAP_OPT_X_TLS */
 
     }
   #endif  /* LDAP_OPT_X_TLS */
 

+  #ifdef LDAP_OPT_X_TLS_CACERTFILE
+  if (eldap_ca_cert_file != NULL)
+    {
+    ldap_set_option(ld, LDAP_OPT_X_TLS_CACERTFILE, eldap_ca_cert_file);
+    }
+  #endif
+  #ifdef LDAP_OPT_X_TLS_CACERTDIR
+  if (eldap_ca_cert_dir != NULL)
+    {
+    ldap_set_option(ld, LDAP_OPT_X_TLS_CACERTDIR, eldap_ca_cert_dir);
+    }
+  #endif
+  #ifdef LDAP_OPT_X_TLS_CERTFILE
+  if (eldap_cert_file != NULL)
+    {
+    ldap_set_option(ld, LDAP_OPT_X_TLS_CERTFILE, eldap_cert_file);
+    }
+  #endif
+  #ifdef LDAP_OPT_X_TLS_KEYFILE
+  if (eldap_cert_key != NULL)
+    {
+    ldap_set_option(ld, LDAP_OPT_X_TLS_KEYFILE, eldap_cert_key);
+    }
+  #endif
+  #ifdef LDAP_OPT_X_TLS_CIPHER_SUITE
+  if (eldap_cipher_suite != NULL)
+    {
+    ldap_set_option(ld, LDAP_OPT_X_TLS_CIPHER_SUITE, eldap_cipher_suite);
+    }
+  #endif
+  #ifdef LDAP_OPT_X_TLS_REQUIRE_CERT
+  if (eldap_require_cert != NULL)
+    {
+    int cert_option = LDAP_OPT_X_TLS_NEVER;
+    if (Ustrcmp(eldap_require_cert, "hard") == 0)
+      {
+      cert_option = LDAP_OPT_X_TLS_HARD;
+      }
+    else if (Ustrcmp(eldap_require_cert, "demand") == 0)
+      {
+      cert_option = LDAP_OPT_X_TLS_DEMAND;
+      }
+    else if (Ustrcmp(eldap_require_cert, "allow") == 0)
+      {
+      cert_option = LDAP_OPT_X_TLS_ALLOW;
+      }
+    else if (Ustrcmp(eldap_require_cert, "try") == 0)
+      {
+      cert_option = LDAP_OPT_X_TLS_TRY;
+      }
+    ldap_set_option(ld, LDAP_OPT_X_TLS_REQUIRE_CERT, &cert_option);
+    }
+  #endif
+

   /* Now add this connection to the chain of cached connections */
 
   lcp = store_get(sizeof(LDAP_CONNECTION));
   /* Now add this connection to the chain of cached connections */
 
   lcp = store_get(sizeof(LDAP_CONNECTION));


@@ -475,6 +519,18 @@ if (!lcp->bound ||
   {
   DEBUG(D_lookup) debug_printf("%sbinding with user=%s password=%s\n",
     (lcp->bound)? "re-" : "", user, password);
   {
   DEBUG(D_lookup) debug_printf("%sbinding with user=%s password=%s\n",
     (lcp->bound)? "re-" : "", user, password);

+#ifdef LDAP_OPT_X_TLS
+  /* The Oracle LDAP libraries (LDAP_LIB_TYPE=SOLARIS) don't support this: */
+  if (eldap_start_tls)
+    {
+        if ( (rc = ldap_start_tls_s(lcp->ld, NULL, NULL)) != LDAP_SUCCESS) {
+            *errmsg = string_sprintf("failed to initiate TLS processing on an "
+                "LDAP session to server %s%s - ldap_start_tls_s() returned %d:"
+                " %s", host, porttext, rc, ldap_err2string(rc));
+            goto RETURN_ERROR;
+        }
+    }
+#endif

   if ((msgid = ldap_bind(lcp->ld, CS user, CS password, LDAP_AUTH_SIMPLE))
        == -1)
     {
   if ((msgid = ldap_bind(lcp->ld, CS user, CS password, LDAP_AUTH_SIMPLE))
        == -1)
     {


@@ -551,6 +607,14 @@ an LDAP library without LDAP_OPT_DEREF. */
 ldap_set_option(lcp->ld, LDAP_OPT_DEREF, (void *)&dereference);
 #endif
 
 ldap_set_option(lcp->ld, LDAP_OPT_DEREF, (void *)&dereference);
 #endif
 

+/* Similarly for the referral setting; should the library follow referrals that
+the LDAP server returns? The conditional is just in case someone uses a library
+without it. */
+
+#if defined(LDAP_OPT_REFERRALS)
+ldap_set_option(lcp->ld, LDAP_OPT_REFERRALS, referrals);
+#endif
+

 /* Start the search on the server. */
 
 DEBUG(D_lookup) debug_printf("Start search\n");
 /* Start the search on the server. */
 
 DEBUG(D_lookup) debug_printf("Start search\n");


@@ -666,10 +730,10 @@ while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
             DEBUG(D_lookup) debug_printf("LDAP attr loop %s:%s\n", attr, value);
 
             if (values != firstval)
             DEBUG(D_lookup) debug_printf("LDAP attr loop %s:%s\n", attr, value);
 
             if (values != firstval)

-              data = string_cat(data, &size, &ptr, US", ", 2);
+              data = string_cat(data, &size, &ptr, US",", 1);

 
             /* For multiple attributes, the data is in quotes. We must escape
 
             /* For multiple attributes, the data is in quotes. We must escape

-            internal quotes, backslashes, newlines. */
+            internal quotes, backslashes, newlines, and must double commas. */

 
             if (attr_count != 1)
               {
 
             if (attr_count != 1)
               {


@@ -678,6 +742,8 @@ while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
                 {
                 if (value[j] == '\n')
                   data = string_cat(data, &size, &ptr, US"\\n", 2);
                 {
                 if (value[j] == '\n')
                   data = string_cat(data, &size, &ptr, US"\\n", 2);

+                else if (value[j] == ',')
+                  data = string_cat(data, &size, &ptr, US",,", 2);

                 else
                   {
                   if (value[j] == '\"' || value[j] == '\\')
                 else
                   {
                   if (value[j] == '\"' || value[j] == '\\')


@@ -687,9 +753,20 @@ while ((rc = ldap_result(lcp->ld, msgid, 0, timeoutptr, &result)) ==
                 }
               }
 
                 }
               }
 

-            /* For single attributes, copy the value verbatim */
+            /* For single attributes, just double commas */
+
+           else
+             {
+             int j;
+             for (j = 0; j < len; j++)
+               {
+               if (value[j] == ',')
+                 data = string_cat(data, &size, &ptr, US",,", 2);
+               else
+                 data = string_cat(data, &size, &ptr, value+j, 1);
+               }
+             }

 
 

-            else data = string_cat(data, &size, &ptr, value, len);

 
             /* Move on to the next value */
 
 
             /* Move on to the next value */
 


@@ -839,18 +916,27 @@ We need to parse the message to find out exactly what's happened. */
   (1) If we get LDAP_SIZELIMIT_EXCEEDED, just carry on, to return the
       truncated result list.
 
   (1) If we get LDAP_SIZELIMIT_EXCEEDED, just carry on, to return the
       truncated result list.
 

-  (2) The range of errors defined by LDAP_NAME_ERROR generally mean "that
+  (2) If we get LDAP_RES_SEARCH_REFERENCE, also just carry on. This was a
+      submitted patch that is reported to "do the right thing" with Solaris
+      LDAP libraries. (The problem it addresses apparently does not occur with
+      Open LDAP.)
+
+  (3) The range of errors defined by LDAP_NAME_ERROR generally mean "that

       object does not, or cannot, exist in the database". For those cases we
       fail the lookup.
 
       object does not, or cannot, exist in the database". For those cases we
       fail the lookup.
 

-  (3) All other non-successes here are treated as some kind of problem with
+  (4) All other non-successes here are treated as some kind of problem with

       the lookup, so return DEFER (which is the default in error_yield).
 */
 
 DEBUG(D_lookup) debug_printf("ldap_parse_result yielded %d: %s\n",
   rc, ldap_err2string(rc));
 
       the lookup, so return DEFER (which is the default in error_yield).
 */
 
 DEBUG(D_lookup) debug_printf("ldap_parse_result yielded %d: %s\n",
   rc, ldap_err2string(rc));
 

-if (rc != LDAP_SUCCESS && rc != LDAP_SIZELIMIT_EXCEEDED)
+if (rc != LDAP_SUCCESS && rc != LDAP_SIZELIMIT_EXCEEDED
+    #ifdef LDAP_RES_SEARCH_REFERENCE
+    && rc != LDAP_RES_SEARCH_REFERENCE
+    #endif
+    )

   {
   *errmsg = string_sprintf("LDAP search failed - error %d: %s%s%s%s%s",
     rc,
   {
   *errmsg = string_sprintf("LDAP search failed - error %d: %s%s%s%s%s",
     rc,


@@ -972,8 +1058,9 @@ BOOL defer_break = FALSE;
 int timelimit = LDAP_NO_LIMIT;
 int sizelimit = LDAP_NO_LIMIT;
 int tcplimit = 0;
 int timelimit = LDAP_NO_LIMIT;
 int sizelimit = LDAP_NO_LIMIT;
 int tcplimit = 0;

-int dereference = LDAP_DEREF_NEVER;

 int sep = 0;
 int sep = 0;

+int dereference = LDAP_DEREF_NEVER;
+void* referrals = LDAP_OPT_ON;

 uschar *url = ldap_url;
 uschar *p;
 uschar *user = NULL;
 uschar *url = ldap_url;
 uschar *p;
 uschar *user = NULL;


@@ -1027,7 +1114,29 @@ while (strncmpic(url, US"ldap", 4) != 0)
         DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
         return DEFER;
         }
         DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
         return DEFER;
         }

+      #endif

 
 

+      #ifdef LDAP_OPT_REFERRALS
+      else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
+        {
+        if (strcmpic(value, US"follow") == 0) referrals = LDAP_OPT_ON;
+        else if (strcmpic(value, US"nofollow") == 0) referrals = LDAP_OPT_OFF;
+        else
+          {
+          *errmsg = string_sprintf("LDAP option REFERRALS is not \"follow\" "
+            "or \"nofollow\"");
+          DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
+          return DEFER;
+          }
+        }
+      #else
+      else if (strncmpic(name, US"REFERRALS=", namelen) == 0)
+        {
+        *errmsg = string_sprintf("LDAP_OP_REFERRALS not defined in this LDAP "
+          "library - cannot use \"referrals\"");
+        DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
+        return DEFER;
+        }

       #endif
 
       else
       #endif
 
       else


@@ -1076,8 +1185,8 @@ if (user != NULL)
 
 DEBUG(D_lookup)
   debug_printf("LDAP parameters: user=%s pass=%s size=%d time=%d connect=%d "
 
 DEBUG(D_lookup)
   debug_printf("LDAP parameters: user=%s pass=%s size=%d time=%d connect=%d "

-    "dereference=%d\n", user, password, sizelimit, timelimit, tcplimit,
-    dereference);
+    "dereference=%d referrals=%s\n", user, password, sizelimit, timelimit,
+    tcplimit, dereference, (referrals == LDAP_OPT_ON)? "on" : "off");

 
 /* If the request is just to check authentication, some credentials must
 be given. The password must not be empty because LDAP binds with an empty
 
 /* If the request is just to check authentication, some credentials must
 be given. The password must not be empty because LDAP binds with an empty


@@ -1114,7 +1223,8 @@ if (Ustrncmp(p, "://", 3) != 0)
 if (eldap_default_servers == NULL || p[3] != '/')
   {
   return perform_ldap_search(url, NULL, 0, search_type, res, errmsg,
 if (eldap_default_servers == NULL || p[3] != '/')
   {
   return perform_ldap_search(url, NULL, 0, search_type, res, errmsg,

-    &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference);
+    &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
+    referrals);

   }
 
 /* Loop through the default servers until OK or FAIL */
   }
 
 /* Loop through the default servers until OK or FAIL */


@@ -1131,7 +1241,8 @@ while ((server = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
     port = Uatoi(colon+1);
     }
   rc = perform_ldap_search(url, server, port, search_type, res, errmsg,
     port = Uatoi(colon+1);
     }
   rc = perform_ldap_search(url, server, port, search_type, res, errmsg,

-    &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference);
+    &defer_break, user, password, sizelimit, timelimit, tcplimit, dereference,
+    referrals);

   if (rc != DEFER || defer_break) return rc;
   }
 
   if (rc != DEFER || defer_break) return rc;
   }
 


@@ -1148,7 +1259,7 @@ return DEFER;
 are handled by a common function, with a flag to differentiate between them.
 The handle and filename arguments are not used. */
 
 are handled by a common function, with a flag to differentiate between them.
 The handle and filename arguments are not used. */
 

-int
+static int

 eldap_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {
 eldap_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {


@@ -1157,7 +1268,7 @@ do_cache = do_cache;
 return(control_ldap_search(ldap_url, SEARCH_LDAP_SINGLE, result, errmsg));
 }
 
 return(control_ldap_search(ldap_url, SEARCH_LDAP_SINGLE, result, errmsg));
 }
 

-int
+static int

 eldapm_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {
 eldapm_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {


@@ -1166,7 +1277,7 @@ do_cache = do_cache;
 return(control_ldap_search(ldap_url, SEARCH_LDAP_MULTIPLE, result, errmsg));
 }
 
 return(control_ldap_search(ldap_url, SEARCH_LDAP_MULTIPLE, result, errmsg));
 }
 

-int
+static int

 eldapdn_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {
 eldapdn_find(void *handle, uschar *filename, uschar *ldap_url, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {


@@ -1192,7 +1303,7 @@ return(control_ldap_search(ldap_url, SEARCH_LDAP_AUTH, result, errmsg));
 
 /* See local README for interface description. */
 
 
 /* See local README for interface description. */
 

-void *
+static void *

 eldap_open(uschar *filename, uschar **errmsg)
 {
 return (void *)(1);    /* Just return something non-null */
 eldap_open(uschar *filename, uschar **errmsg)
 {
 return (void *)(1);    /* Just return something non-null */


@@ -1207,7 +1318,7 @@ return (void *)(1);    /* Just return something non-null */
 /* See local README for interface description.
 Make sure that eldap_dn does not refer to reclaimed or worse, freed store */
 
 /* See local README for interface description.
 Make sure that eldap_dn does not refer to reclaimed or worse, freed store */
 

-void
+static void

 eldap_tidy(void)
 {
 LDAP_CONNECTION *lcp = NULL;
 eldap_tidy(void)
 {
 LDAP_CONNECTION *lcp = NULL;


@@ -1303,7 +1414,7 @@ quote_ldap_dn, respectively. */
 
 
 
 
 
 

-uschar *
+static uschar *

 eldap_quote(uschar *s, uschar *opt)
 {
 register int c;
 eldap_quote(uschar *s, uschar *opt)
 {
 register int c;


@@ -1422,6 +1533,66 @@ else
 return quoted;
 }
 
 return quoted;
 }
 

-#endif  /* LOOKUP_LDAP */
+
+
+/*************************************************
+*         Version reporting entry point          *
+*************************************************/
+
+/* See local README for interface description. */
+
+#include "../version.h"
+
+void
+ldap_version_report(FILE *f)
+{
+#ifdef DYNLOOKUP
+fprintf(f, "Library version: LDAP: Exim version %s\n", EXIM_VERSION_STR);
+#endif
+}
+
+
+static lookup_info ldap_lookup_info = {
+  US"ldap",                      /* lookup name */
+  lookup_querystyle,             /* query-style lookup */
+  eldap_open,                    /* open function */
+  NULL,                          /* check function */
+  eldap_find,                    /* find function */
+  NULL,                          /* no close function */
+  eldap_tidy,                    /* tidy function */
+  eldap_quote,                   /* quoting function */
+  ldap_version_report            /* version reporting */
+};
+
+static lookup_info ldapdn_lookup_info = {
+  US"ldapdn",                     /* lookup name */
+  lookup_querystyle,             /* query-style lookup */
+  eldap_open,       /* sic */    /* open function */
+  NULL,                          /* check function */
+  eldapdn_find,                  /* find function */
+  NULL,                          /* no close function */
+  eldap_tidy,       /* sic */    /* tidy function */
+  eldap_quote,      /* sic */    /* quoting function */
+  NULL                           /* no version reporting (redundant) */
+};
+
+static lookup_info ldapm_lookup_info = {
+  US"ldapm",                     /* lookup name */
+  lookup_querystyle,             /* query-style lookup */
+  eldap_open,       /* sic */    /* open function */
+  NULL,                          /* check function */
+  eldapm_find,                   /* find function */
+  NULL,                          /* no close function */
+  eldap_tidy,       /* sic */    /* tidy function */
+  eldap_quote,      /* sic */    /* quoting function */
+  NULL                           /* no version reporting (redundant) */
+};
+
+#ifdef DYNLOOKUP
+#define ldap_lookup_module_info _lookup_module_info
+#endif
+
+static lookup_info *_lookup_list[] = { &ldap_lookup_info, &ldapdn_lookup_info, &ldapm_lookup_info };
+lookup_module_info ldap_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };

 
 /* End of lookups/ldap.c */
 
 /* End of lookups/ldap.c */