Adding upstream version 4.92.upstream/4.92upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 532 insertions, 0 deletions

diff --git a/src/tlscert-openssl.c b/src/tlscert-openssl.c
new file mode 100644
index 0000000..7e0128e
--- /dev/null
+++ b/src/tlscert-openssl.c
@@ -0,0 +1,532 @@
+/*************************************************
+*     Exim - an Internet mail transport agent    *
+*************************************************/
+
+/* Copyright (c) Jeremy Harris 2014 - 2018 */
+
+/* This module provides TLS (aka SSL) support for Exim using the OpenSSL
+library. It is #included into the tls.c file when that library is used.
+*/
+
+
+/* Heading stuff */
+
+#include <openssl/lhash.h>
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <openssl/rand.h>
+#include <openssl/x509v3.h>
+
+#if OPENSSL_VERSION_NUMBER >= 0x10100000L
+# define EXIM_HAVE_ASN1_MACROS
+#endif
+
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+# define ASN1_STRING_get0_data ASN1_STRING_data
+#endif
+
+/*****************************************************
+*  Export/import a certificate, binary/printable
+*****************************************************/
+int
+tls_export_cert(uschar * buf, size_t buflen, void * cert)
+{
+BIO * bp = BIO_new(BIO_s_mem());
+int fail;
+
+if ((fail = PEM_write_bio_X509(bp, (X509 *)cert) ? 0 : 1))
+  log_write(0, LOG_MAIN, "TLS error in certificate export: %s",
+    ERR_error_string(ERR_get_error(), NULL));
+else
+  {
+  char * cp = CS buf;
+  int n;
+  buflen -= 2;
+  for(;;)
+    {
+    if ((n = BIO_gets(bp, cp, (int)buflen)) <= 0) break;
+    cp += n+1;
+    buflen -= n+1;
+    cp[-2] = '\\'; cp[-1] = 'n'; /* newline->"\n" */
+    }				 /* compat with string_printing() */
+  *cp = '\0';
+  }
+
+BIO_free(bp);
+return fail;
+}
+
+int
+tls_import_cert(const uschar * buf, void ** cert)
+{
+void * reset_point = store_get(0);
+const uschar * cp = string_unprinting(US buf);
+BIO * bp;
+X509 * x = *(X509 **)cert;
+int fail = 0;
+
+if (x) X509_free(x);
+
+bp = BIO_new_mem_buf(US cp, -1);
+if (!(x = PEM_read_bio_X509(bp, NULL, 0, NULL)))
+  {
+  log_write(0, LOG_MAIN, "TLS error in certificate import: %s",
+    ERR_error_string(ERR_get_error(), NULL));
+  fail = 1;
+  }
+else
+  *cert = (void *)x;
+BIO_free(bp);
+store_reset(reset_point);
+return fail;
+}
+
+void
+tls_free_cert(void ** cert)
+{
+X509 * x = *(X509 **)cert;
+if (x)
+  {
+  X509_free(x);
+  *cert = NULL;
+  }
+}
+
+
+/*****************************************************
+*  Certificate field extraction routines
+*****************************************************/
+
+/* First, some internal service functions */
+
+static uschar *
+badalloc(void)
+{
+expand_string_message = US"allocation failure";
+return NULL;
+}
+
+static uschar *
+bio_string_copy(BIO * bp, int len)
+{
+uschar * cp = US"";
+len = len > 0 ? (int) BIO_get_mem_data(bp, &cp) : 0;
+cp = string_copyn(cp, len);
+BIO_free(bp);
+return cp;
+}
+
+static uschar *
+asn1_time_copy(const ASN1_TIME * asntime, uschar * mod)
+{
+uschar * s = NULL;
+BIO * bp = BIO_new(BIO_s_mem());
+int len;
+
+if (!bp)
+  return badalloc();
+len = ASN1_TIME_print(bp, asntime);
+len = len > 0 ? (int) BIO_get_mem_data(bp, CSS &s) : 0;
+
+if (mod && Ustrcmp(mod, "raw") == 0)		/* native ASN */
+  s = string_copyn(s, len);
+else
+  {
+  struct tm tm;
+  struct tm * tm_p = &tm;
+  BOOL mod_tz = TRUE;
+  uschar * tz = to_tz(US"GMT0");    /* need to call strptime with baseline TZ */
+
+  /* Parse OpenSSL ASN1_TIME_print output.  A shame there seems to
+  be no other interface for the times.
+  */
+
+  /*XXX %Z might be glibc-specific?  Solaris has it, at least*/
+  /*XXX should we switch to POSIX locale for this? */
+  tm.tm_isdst = 0;
+  if (!len || !strptime(CCS s, "%b %e %T %Y %Z", &tm))
+    expand_string_message = US"failed time conversion";
+
+  else
+    {
+    time_t t = mktime(&tm);	/* make the tm self-consistent */
+
+    if (mod && Ustrcmp(mod, "int") == 0)	/* seconds since epoch */
+      s = string_sprintf(TIME_T_FMT, t);
+
+    else
+      {
+      if (!f.timestamps_utc)	/* decoded string in local TZ */
+	{				/* shift to local TZ */
+	restore_tz(tz);
+	mod_tz = FALSE;
+	tm_p = localtime(&t);
+	}
+      /* "utc" is default, and rfc5280 says cert times should be Zulu */
+
+      /* convert to string in our format */
+      len = 32;
+      s = store_get(len);
+      strftime(CS s, (size_t)len, "%b %e %T %Y %z", tm_p);
+      }
+    }
+
+  if (mod_tz)
+    restore_tz(tz);
+  }
+BIO_free(bp);
+return s;
+}
+
+static uschar *
+x509_name_copy(X509_NAME * name)
+{
+BIO * bp = BIO_new(BIO_s_mem());
+int len_good;
+
+if (!bp) return badalloc();
+
+len_good =
+  X509_NAME_print_ex(bp, name, 0, XN_FLAG_RFC2253) >= 0
+  ? 1 : 0;
+return bio_string_copy(bp, len_good);
+}
+
+/**/
+/* 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)
+{
+uschar * cp = x509_name_copy(X509_get_issuer_name((X509 *)cert));
+return mod ? tls_field_from_dn(cp, mod) : cp;
+}
+
+uschar *
+tls_cert_not_before(void * cert, uschar * mod)
+{
+return asn1_time_copy(X509_get_notBefore((X509 *)cert), mod);
+}
+
+uschar *
+tls_cert_not_after(void * cert, uschar * mod)
+{
+return asn1_time_copy(X509_get_notAfter((X509 *)cert), mod);
+}
+
+uschar *
+tls_cert_serial_number(void * cert, uschar * mod)
+{
+uschar txt[256];
+BIO * bp = BIO_new(BIO_s_mem());
+int len;
+
+if (!bp) return badalloc();
+
+len = i2a_ASN1_INTEGER(bp, X509_get_serialNumber((X509 *)cert));
+if (len < sizeof(txt))
+  BIO_read(bp, txt, len);
+else
+  len = 0;
+BIO_free(bp);
+return string_copynlc(txt, len);	/* lowercase */
+}
+
+uschar *
+tls_cert_signature(void * cert, uschar * mod)
+{
+uschar * cp = NULL;
+BIO * bp = BIO_new(BIO_s_mem());
+
+if (!bp) return badalloc();
+
+if (X509_print_ex(bp, (X509 *)cert, 0,
+  X509_FLAG_NO_HEADER | X509_FLAG_NO_VERSION | X509_FLAG_NO_SERIAL |
+  X509_FLAG_NO_SIGNAME | X509_FLAG_NO_ISSUER | X509_FLAG_NO_VALIDITY |
+  X509_FLAG_NO_SUBJECT | X509_FLAG_NO_PUBKEY | X509_FLAG_NO_EXTENSIONS |
+  /* X509_FLAG_NO_SIGDUMP is the missing one */
+  X509_FLAG_NO_AUX) == 1)
+  {
+  long len = BIO_get_mem_data(bp, &cp);
+
+  /* Strip leading "Signature Algorithm" line */
+  while (*cp && *cp != '\n') { cp++; len--; }
+
+  cp = string_copyn(cp+1, len-1);
+  }
+BIO_free(bp);
+return cp;
+}
+
+uschar *
+tls_cert_signature_algorithm(void * cert, uschar * mod)
+{
+uschar * cp = NULL;
+BIO * bp = BIO_new(BIO_s_mem());
+
+if (!bp) return badalloc();
+
+if (X509_print_ex(bp, (X509 *)cert, 0,
+  X509_FLAG_NO_HEADER | X509_FLAG_NO_VERSION | X509_FLAG_NO_SERIAL |
+  /* X509_FLAG_NO_SIGNAME is the missing one */
+  X509_FLAG_NO_ISSUER | X509_FLAG_NO_VALIDITY |
+  X509_FLAG_NO_SUBJECT | X509_FLAG_NO_PUBKEY | X509_FLAG_NO_EXTENSIONS |
+  X509_FLAG_NO_SIGDUMP | X509_FLAG_NO_AUX) == 1)
+  {
+  long len = BIO_get_mem_data(bp, &cp);
+
+  /* Strip leading "    Signature Algorithm: " and trailing newline */
+  while (*cp && *cp != ':') { cp++; len--; }
+  do { cp++; len--; } while (*cp && *cp == ' ');
+  if (cp[len-1] == '\n') len--;
+
+  cp = string_copyn(cp, len);
+  }
+BIO_free(bp);
+return cp;
+}
+
+uschar *
+tls_cert_subject(void * cert, uschar * mod)
+{
+uschar * cp = x509_name_copy(X509_get_subject_name((X509 *)cert));
+return mod ? tls_field_from_dn(cp, mod) : cp;
+}
+
+uschar *
+tls_cert_version(void * cert, uschar * mod)
+{
+return string_sprintf("%ld", X509_get_version((X509 *)cert));
+}
+
+uschar *
+tls_cert_ext_by_oid(void * cert, uschar * oid, int idx)
+{
+int nid = OBJ_create(CS oid, "", "");
+int nidx = X509_get_ext_by_NID((X509 *)cert, nid, idx);
+X509_EXTENSION * ex = X509_get_ext((X509 *)cert, nidx);
+ASN1_OCTET_STRING * adata = X509_EXTENSION_get_data(ex);
+BIO * bp = BIO_new(BIO_s_mem());
+long len;
+uschar * cp1;
+uschar * cp2;
+uschar * cp3;
+
+if (!bp) return badalloc();
+
+#ifdef EXIM_HAVE_ASN1_MACROS
+ASN1_STRING_print(bp, adata);
+#else
+M_ASN1_OCTET_STRING_print(bp, adata);
+#endif
+
+/* binary data, DER encoded */
+/* just dump for now */
+len = BIO_get_mem_data(bp, &cp1);
+cp3 = cp2 = store_get(len*3+1);
+
+while(len)
+  {
+  cp2 += sprintf(CS cp2, "%.2x ", *cp1++);
+  len--;
+  }
+cp2[-1] = '\0';
+
+return cp3;
+}
+
+uschar *
+tls_cert_subject_altname(void * cert, uschar * mod)
+{
+gstring * list = NULL;
+STACK_OF(GENERAL_NAME) * san = (STACK_OF(GENERAL_NAME) *)
+  X509_get_ext_d2i((X509 *)cert, NID_subject_alt_name, NULL, NULL);
+uschar osep = '\n';
+uschar * tag = US"";
+uschar * ele;
+int match = -1;
+int len;
+
+if (!san) return NULL;
+
+while (mod && *mod)
+  {
+  if (*mod == '>' && *++mod) osep = *mod++;
+  else if (Ustrncmp(mod,"dns",3)==0) { match = GEN_DNS; mod += 3; }
+  else if (Ustrncmp(mod,"uri",3)==0) { match = GEN_URI; mod += 3; }
+  else if (Ustrncmp(mod,"mail",4)==0) { match = GEN_EMAIL; mod += 4; }
+  else mod++;
+
+  if (*mod == ',') mod++;
+  }
+
+while (sk_GENERAL_NAME_num(san) > 0)
+  {
+  GENERAL_NAME * namePart = sk_GENERAL_NAME_pop(san);
+  if (match != -1 && match != namePart->type)
+    continue;
+  switch (namePart->type)
+    {
+    case GEN_DNS:
+      tag = US"DNS";
+      ele = US ASN1_STRING_get0_data(namePart->d.dNSName);
+      len = ASN1_STRING_length(namePart->d.dNSName);
+      break;
+    case GEN_URI:
+      tag = US"URI";
+      ele = US ASN1_STRING_get0_data(namePart->d.uniformResourceIdentifier);
+      len = ASN1_STRING_length(namePart->d.uniformResourceIdentifier);
+      break;
+    case GEN_EMAIL:
+      tag = US"MAIL";
+      ele = US ASN1_STRING_get0_data(namePart->d.rfc822Name);
+      len = ASN1_STRING_length(namePart->d.rfc822Name);
+      break;
+    default:
+      continue;	/* ignore unrecognised types */
+    }
+  if (ele[len])	/* not nul-terminated */
+    ele = string_copyn(ele, len);
+
+  if (Ustrlen(ele) == len)	/* ignore any with embedded nul */
+    list = string_append_listele(list, osep,
+	  match == -1 ? string_sprintf("%s=%s", tag, ele) : ele);
+  }
+
+sk_GENERAL_NAME_free(san);
+return string_from_gstring(list);
+}
+
+uschar *
+tls_cert_ocsp_uri(void * cert, uschar * mod)
+{
+STACK_OF(ACCESS_DESCRIPTION) * ads = (STACK_OF(ACCESS_DESCRIPTION) *)
+  X509_get_ext_d2i((X509 *)cert, NID_info_access, NULL, NULL);
+int adsnum = sk_ACCESS_DESCRIPTION_num(ads);
+int i;
+uschar sep = '\n';
+gstring * list = NULL;
+
+if (mod)
+  if (*mod == '>' && *++mod) sep = *mod++;
+
+for (i = 0; i < adsnum; i++)
+  {
+  ACCESS_DESCRIPTION * ad = sk_ACCESS_DESCRIPTION_value(ads, i);
+
+  if (ad && OBJ_obj2nid(ad->method) == NID_ad_OCSP)
+    list = string_append_listele_n(list, sep,
+      US ASN1_STRING_get0_data(ad->location->d.ia5),
+      ASN1_STRING_length(ad->location->d.ia5));
+  }
+sk_ACCESS_DESCRIPTION_free(ads);
+return string_from_gstring(list);
+}
+
+uschar *
+tls_cert_crl_uri(void * cert, uschar * mod)
+{
+STACK_OF(DIST_POINT) * dps = (STACK_OF(DIST_POINT) *)
+  X509_get_ext_d2i((X509 *)cert,  NID_crl_distribution_points,
+    NULL, NULL);
+DIST_POINT * dp;
+int dpsnum = sk_DIST_POINT_num(dps);
+int i;
+uschar sep = '\n';
+gstring * list = NULL;
+
+if (mod)
+  if (*mod == '>' && *++mod) sep = *mod++;
+
+if (dps) for (i = 0; i < dpsnum; i++)
+  if ((dp = sk_DIST_POINT_value(dps, i)))
+    {
+    STACK_OF(GENERAL_NAME) * names = dp->distpoint->name.fullname;
+    GENERAL_NAME * np;
+    int nnum = sk_GENERAL_NAME_num(names);
+    int j;
+
+    for (j = 0; j < nnum; j++)
+      if (  (np = sk_GENERAL_NAME_value(names, j))
+	 && np->type == GEN_URI
+	 )
+	list = string_append_listele_n(list, sep,
+	  US ASN1_STRING_get0_data(np->d.uniformResourceIdentifier),
+	  ASN1_STRING_length(np->d.uniformResourceIdentifier));
+    }
+sk_DIST_POINT_free(dps);
+return string_from_gstring(list);
+}
+
+
+
+/*****************************************************
+*  Certificate operator routines
+*****************************************************/
+uschar *
+tls_cert_der_b64(void * cert)
+{
+BIO * bp = BIO_new(BIO_s_mem());
+uschar * cp = NULL;
+
+if (!i2d_X509_bio(bp, (X509 *)cert))
+  log_write(0, LOG_MAIN, "TLS error in certificate export: %s",
+    ERR_error_string(ERR_get_error(), NULL));
+else
+  {
+  long len = BIO_get_mem_data(bp, &cp);
+  cp = b64encode(cp, (int)len);
+  }
+
+BIO_free(bp);
+return cp;
+}
+
+
+static uschar *
+fingerprint(X509 * cert, const EVP_MD * fdig)
+{
+int j;
+unsigned int n;
+uschar md[EVP_MAX_MD_SIZE];
+uschar * cp;
+
+if (!X509_digest(cert,fdig,md,&n))
+  {
+  expand_string_message = US"tls_cert_fprt: out of mem\n";
+  return NULL;
+  }
+cp = store_get(n*2+1);
+for (j = 0; j < (int)n; j++) sprintf(CS cp+2*j, "%02X", md[j]);
+return(cp);
+}
+
+uschar *
+tls_cert_fprt_md5(void * cert)
+{
+return fingerprint((X509 *)cert, EVP_md5());
+}
+
+uschar *
+tls_cert_fprt_sha1(void * cert)
+{
+return fingerprint((X509 *)cert, EVP_sha1());
+}
+
+uschar *
+tls_cert_fprt_sha256(void * cert)
+{
+return fingerprint((X509 *)cert, EVP_sha256());
+}
+
+
+/* vi: aw ai sw=2
+*/
+/* End of tlscert-openssl.c */