X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/812a604525eef4993d6ed165d455c8309ae72c36..fc6fb551537b5af8988576071ff6e1240cff269f:/src/src/tlscert-gnu.c

diff --git a/src/src/tlscert-gnu.c b/src/src/tlscert-gnu.c
index 085e05689..385fb8d42 100644
--- a/src/src/tlscert-gnu.c
+++ b/src/src/tlscert-gnu.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) Jeremy Harris 2014 */
+/* Copyright (c) Jeremy Harris 2014 - 2017 */
 
 /* This file provides TLS/SSL support for Exim using the GnuTLS library,
 one of the available supported implementations.  This file is #included into
@@ -26,12 +26,16 @@ tls_export_cert(uschar * buf, size_t buflen, void * cert)
 {
 size_t sz = buflen;
 void * reset_point = store_get(0);
-int fail = 0;
-uschar * cp;
+int fail;
+const uschar * cp;
 
-if (gnutls_x509_crt_export((gnutls_x509_crt_t)cert,
-    GNUTLS_X509_FMT_PEM, buf, &sz))
+if ((fail = gnutls_x509_crt_export((gnutls_x509_crt_t)cert,
+    GNUTLS_X509_FMT_PEM, buf, &sz)))
+  {
+  log_write(0, LOG_MAIN, "TLS error in certificate export: %s",
+    gnutls_strerror(fail));
   return 1;
+  }
 if ((cp = string_printing(buf)) != buf)
   {
   Ustrncpy(buf, cp, buflen);
@@ -47,16 +51,24 @@ tls_import_cert(const uschar * buf, void ** cert)
 {
 void * reset_point = store_get(0);
 gnutls_datum_t datum;
-gnutls_x509_crt_t crt;
+gnutls_x509_crt_t crt = *(gnutls_x509_crt_t *)cert;
 int fail = 0;
 
-gnutls_global_init();
+if (crt)
+  gnutls_x509_crt_deinit(crt);
+else
+  gnutls_global_init();
+
 gnutls_x509_crt_init(&crt);
 
 datum.data = string_unprinting(US buf);
 datum.size = Ustrlen(datum.data);
-if (gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM))
+if ((fail = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM)))
+  {
+  log_write(0, LOG_MAIN, "TLS error in certificate import: %s",
+    gnutls_strerror(fail));
   fail = 1;
+  }
 else
   *cert = (void *)crt;
 
@@ -65,15 +77,23 @@ return fail;
 }
 
 void
-tls_free_cert(void * cert)
+tls_free_cert(void ** cert)
 {
-gnutls_x509_crt_deinit((gnutls_x509_crt_t) cert);
-gnutls_global_deinit();
+gnutls_x509_crt_t crt = *(gnutls_x509_crt_t *)cert;
+if (crt)
+  {
+  gnutls_x509_crt_deinit(crt);
+  gnutls_global_deinit();
+  *cert = NULL;
+  }
 }
 
 /*****************************************************
 *  Certificate field extraction routines
 *****************************************************/
+
+/* First, some internal service functions */
+
 static uschar *
 g_err(const char * tag, const char * from, int gnutls_err)
 {
@@ -84,15 +104,36 @@ return NULL;
 
 
 static uschar *
-time_copy(time_t t)
+time_copy(time_t t, uschar * mod)
 {
-uschar * cp = store_get(32);
-struct tm * tp = gmtime(&t);
-size_t len = strftime(CS cp, 32, "%b %e %T %Y %Z", tp);
+uschar * cp;
+size_t len = 32;
+
+if (mod && Ustrcmp(mod, "int") == 0)
+  return string_sprintf("%u", (unsigned)t);
+
+cp = store_get(len);
+if (timestamps_utc)
+  {
+  uschar * tz = to_tz(US"GMT0");
+  len = strftime(CS cp, len, "%b %e %T %Y %Z", gmtime(&t));
+  restore_tz(tz);
+  }
+else
+  len = strftime(CS cp, len, "%b %e %T %Y %Z", localtime(&t));
 return len > 0 ? cp : NULL;
 }
 
+
 /**/
+/* Now the extractors, called from expand.c
+Arguments:
+  cert		The certificate
+  mod		Optional modifiers for the operator
+
+Return:
+  Allocated string with extracted value
+*/
 
 uschar *
 tls_cert_issuer(void * cert, uschar * mod)
@@ -101,12 +142,12 @@ uschar * cp = NULL;
 int ret;
 size_t siz = 0;
 
-if ((ret = gnutls_x509_crt_get_issuer_dn(cert, cp, &siz))
+if ((ret = gnutls_x509_crt_get_issuer_dn(cert, CS cp, &siz))
     != GNUTLS_E_SHORT_MEMORY_BUFFER)
   return g_err("gi0", __FUNCTION__, ret);
 
 cp = store_get(siz);
-if ((ret = gnutls_x509_crt_get_issuer_dn(cert, cp, &siz)) < 0)
+if ((ret = gnutls_x509_crt_get_issuer_dn(cert, CS cp, &siz)) < 0)
   return g_err("gi1", __FUNCTION__, ret);
 
 return mod ? tls_field_from_dn(cp, mod) : cp;
@@ -116,14 +157,16 @@ uschar *
 tls_cert_not_after(void * cert, uschar * mod)
 {
 return time_copy(
-  gnutls_x509_crt_get_expiration_time((gnutls_x509_crt_t)cert));
+  gnutls_x509_crt_get_expiration_time((gnutls_x509_crt_t)cert),
+  mod);
 }
 
 uschar *
 tls_cert_not_before(void * cert, uschar * mod)
 {
 return time_copy(
-  gnutls_x509_crt_get_activation_time((gnutls_x509_crt_t)cert));
+  gnutls_x509_crt_get_activation_time((gnutls_x509_crt_t)cert),
+  mod);
 }
 
 uschar *
@@ -133,12 +176,14 @@ uschar bin[50], txt[150];
 size_t sz = sizeof(bin);
 uschar * sp;
 uschar * dp;
+int ret;
 
-if (gnutls_x509_crt_get_serial((gnutls_x509_crt_t)cert,
-    bin, &sz) || sz > sizeof(bin))
-  return NULL;
-for(dp = txt, sp = bin; sz; dp += 2, sp++, sz--)
-  sprintf(dp, "%.2x", *sp);
+if ((ret = gnutls_x509_crt_get_serial((gnutls_x509_crt_t)cert,
+    bin, &sz)))
+  return g_err("gs0", __FUNCTION__, ret);
+
+for(dp = txt, sp = bin; sz; sz--)
+  dp += sprintf(CS dp, "%.2x", *sp++);
 for(sp = txt; sp[0]=='0' && sp[1]; ) sp++;	/* leading zeroes */
 return string_copy(sp);
 }
@@ -146,22 +191,22 @@ return string_copy(sp);
 uschar *
 tls_cert_signature(void * cert, uschar * mod)
 {
-uschar * cp1;
+uschar * cp1 = NULL;
 uschar * cp2;
 uschar * cp3;
 size_t len = 0;
 int ret;
 
-if ((ret = gnutls_x509_crt_get_signature((gnutls_x509_crt_t)cert, cp1, &len))
+if ((ret = gnutls_x509_crt_get_signature((gnutls_x509_crt_t)cert, CS cp1, &len))
     != GNUTLS_E_SHORT_MEMORY_BUFFER)
   return g_err("gs0", __FUNCTION__, ret);
 
 cp1 = store_get(len*4+1);
-if (gnutls_x509_crt_get_signature((gnutls_x509_crt_t)cert, cp1, &len) != 0)
+if (gnutls_x509_crt_get_signature((gnutls_x509_crt_t)cert, CS cp1, &len) != 0)
   return g_err("gs1", __FUNCTION__, ret);
 
-for(cp3 = cp2 = cp1+len; cp1 < cp2; cp3 += 3, cp1++)
-  sprintf(cp3, "%.2x ", *cp1);
+for(cp3 = cp2 = cp1+len; cp1 < cp2; cp1++)
+  cp3 += sprintf(CS cp3, "%.2x ", *cp1);
 cp3[-1]= '\0';
 
 return cp2;
@@ -172,7 +217,7 @@ tls_cert_signature_algorithm(void * cert, uschar * mod)
 {
 gnutls_sign_algorithm_t algo =
   gnutls_x509_crt_get_signature_algorithm((gnutls_x509_crt_t)cert);
-return algo < 0 ? NULL : string_copy(gnutls_sign_get_name(algo));
+return algo < 0 ? NULL : string_copy(US gnutls_sign_get_name(algo));
 }
 
 uschar *
@@ -182,12 +227,12 @@ uschar * cp = NULL;
 int ret;
 size_t siz = 0;
 
-if ((ret = gnutls_x509_crt_get_dn(cert, cp, &siz))
+if ((ret = gnutls_x509_crt_get_dn(cert, CS cp, &siz))
     != GNUTLS_E_SHORT_MEMORY_BUFFER)
   return g_err("gs0", __FUNCTION__, ret);
 
 cp = store_get(siz);
-if ((ret = gnutls_x509_crt_get_dn(cert, cp, &siz)) < 0)
+if ((ret = gnutls_x509_crt_get_dn(cert, CS cp, &siz)) < 0)
   return g_err("gs1", __FUNCTION__, ret);
 
 return mod ? tls_field_from_dn(cp, mod) : cp;
@@ -210,22 +255,22 @@ unsigned int crit;
 int ret;
 
 ret = gnutls_x509_crt_get_extension_by_oid ((gnutls_x509_crt_t)cert,
-  oid, idx, cp1, &siz, &crit);
+  oid, idx, CS cp1, &siz, &crit);
 if (ret != GNUTLS_E_SHORT_MEMORY_BUFFER)
   return g_err("ge0", __FUNCTION__, ret);
 
 cp1 = store_get(siz*4 + 1);
 
 ret = gnutls_x509_crt_get_extension_by_oid ((gnutls_x509_crt_t)cert,
-  oid, idx, cp1, &siz, &crit);
+  oid, idx, CS cp1, &siz, &crit);
 if (ret < 0)
   return g_err("ge1", __FUNCTION__, ret);
 
 /* binary data, DER encoded */
 
 /* just dump for now */
-for(cp3 = cp2 = cp1+siz; cp1 < cp2; cp3 += 3, cp1++)
-  sprintf(cp3, "%.2x ", *cp1);
+for(cp3 = cp2 = cp1+siz; cp1 < cp2; cp1++)
+  cp3 += sprintf(CS cp3, "%.2x ", *cp1);
 cp3[-1]= '\0';
 
 return cp2;
@@ -234,7 +279,7 @@ return cp2;
 uschar *
 tls_cert_subject_altname(void * cert, uschar * mod)
 {
-uschar * list = NULL;
+gstring * list = NULL;
 int index;
 size_t siz;
 int ret;
@@ -259,10 +304,10 @@ for(index = 0;; index++)
   {
   siz = 0;
   switch(ret = gnutls_x509_crt_get_subject_alt_name(
-    (gnutls_x509_crt_t)cert, index, NULL, &siz, NULL))
+      (gnutls_x509_crt_t)cert, index, NULL, &siz, NULL))
     {
     case GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE:
-      return list;	/* no more elements; normal exit */
+      return string_from_gstring(list);	/* no more elements; normal exit */
 
     case GNUTLS_E_SHORT_MEMORY_BUFFER:
       break;
@@ -277,16 +322,17 @@ for(index = 0;; index++)
     return g_err("gs1", __FUNCTION__, ret);
   ele[siz] = '\0';
 
-  if (match != -1 && match != ret)
+  if (  match != -1 && match != ret	/* wrong type of SAN */
+     || Ustrlen(ele) != siz)		/* contains a NUL */
     continue;
   switch (ret)
     {
     case GNUTLS_SAN_DNSNAME:    tag = US"DNS";  break;
-    case GNUTLS_SAN_URI:        tag = US"URI";  break; 
+    case GNUTLS_SAN_URI:        tag = US"URI";  break;
     case GNUTLS_SAN_RFC822NAME: tag = US"MAIL"; break;
     default: continue;        /* ignore unrecognised types */
     }
-  list = string_append_listele(list, sep, 
+  list = string_append_listele(list, sep,
           match == -1 ? string_sprintf("%s=%s", tag, ele) : ele);
   }
 /*NOTREACHED*/
@@ -300,7 +346,7 @@ gnutls_datum_t uri;
 int ret;
 uschar sep = '\n';
 int index;
-uschar * list = NULL;
+gstring * list = NULL;
 
 if (mod)
   if (*mod == '>' && *++mod) sep = *mod++;
@@ -311,18 +357,17 @@ for(index = 0;; index++)
 	  index, GNUTLS_IA_OCSP_URI, &uri, NULL);
 
   if (ret == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
-    return list;
+    return string_from_gstring(list);
   if (ret < 0)
     return g_err("gai", __FUNCTION__, ret);
 
-  list = string_append_listele(list, sep,
-	    string_copyn(uri.data, uri.size));
+  list = string_append_listele_n(list, sep, uri.data, uri.size);
   }
 /*NOTREACHED*/
 
 #else
 
-expand_string_message = 
+expand_string_message =
   string_sprintf("%s: OCSP support with GnuTLS requires version 3.0.0\n",
     __FUNCTION__);
 return NULL;
@@ -337,7 +382,7 @@ int ret;
 size_t siz;
 uschar sep = '\n';
 int index;
-uschar * list = NULL;
+gstring * list = NULL;
 uschar * ele;
 
 if (mod)
@@ -350,20 +395,19 @@ for(index = 0;; index++)
     (gnutls_x509_crt_t)cert, index, NULL, &siz, NULL, NULL))
     {
     case GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE:
-      return list;
+      return string_from_gstring(list);
     case GNUTLS_E_SHORT_MEMORY_BUFFER:
       break;
     default:
       return g_err("gc0", __FUNCTION__, ret);
     }
 
-  ele = store_get(siz+1);
+  ele = store_get(siz);
   if ((ret = gnutls_x509_crt_get_crl_dist_points(
       (gnutls_x509_crt_t)cert, index, ele, &siz, NULL, NULL)) < 0)
     return g_err("gc1", __FUNCTION__, ret);
 
-  ele[siz] = '\0';
-  list = string_append_listele(list, sep, ele);
+  list = string_append_listele_n(list, sep, ele, siz);
   }
 /*NOTREACHED*/
 }
@@ -372,6 +416,28 @@ for(index = 0;; index++)
 /*****************************************************
 *  Certificate operator routines
 *****************************************************/
+uschar *
+tls_cert_der_b64(void * cert)
+{
+size_t len = 0;
+uschar * cp = NULL;
+int fail;
+
+if (  (fail = gnutls_x509_crt_export((gnutls_x509_crt_t)cert,
+	GNUTLS_X509_FMT_DER, cp, &len)) != GNUTLS_E_SHORT_MEMORY_BUFFER
+   || !(cp = store_get((int)len))
+   || (fail = gnutls_x509_crt_export((gnutls_x509_crt_t)cert,
+        GNUTLS_X509_FMT_DER, cp, &len))
+   )
+  {
+  log_write(0, LOG_MAIN, "TLS error in certificate export: %s",
+    gnutls_strerror(fail));
+  return NULL;
+  }
+return b64encode(cp, (int)len);
+}
+
+
 static uschar *
 fingerprint(gnutls_x509_crt_t cert, gnutls_digest_algorithm_t algo)
 {
@@ -389,8 +455,8 @@ cp = store_get(siz*3+1);
 if ((ret = gnutls_x509_crt_get_fingerprint(cert, algo, cp, &siz)) < 0)
   return g_err("gf1", __FUNCTION__, ret);
 
-for (cp3 = cp2 = cp+siz; cp < cp2; cp++, cp3+=2)
-  sprintf(cp3, "%02X",*cp);
+for (cp3 = cp2 = cp+siz; cp < cp2; cp++)
+  cp3 += sprintf(CS cp3, "%02X", *cp);
 return cp2;
 }