X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/d5b80e59458182b2d557a929a18cb8c70cd56b68..a85c067ba6c6940512cf57ec213277a370d87e70:/src/src/rfc2047.c

diff --git a/src/src/rfc2047.c b/src/src/rfc2047.c
index 041a18858..af8993695 100644
--- a/src/src/rfc2047.c
+++ b/src/src/rfc2047.c
@@ -2,8 +2,10 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) The Exim Maintainers 2020 - 2022 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
 /* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-only */
 
 /* This file contains a function for decoding message header lines that may
 contain encoded "words" according to the rules described in
@@ -46,7 +48,7 @@ rfc2047_qpdecode(uschar *string, uschar **ptrptr)
 int len = 0;
 uschar *ptr;
 
-ptr = *ptrptr = store_get(Ustrlen(string) + 1);  /* No longer than this */
+ptr = *ptrptr = store_get(Ustrlen(string) + 1, string);  /* No longer than this */
 
 while (*string != 0)
   {
@@ -185,13 +187,13 @@ Returns:         the decoded, converted string, or NULL on error; if there are
 */
 
 uschar *
-rfc2047_decode2(uschar *string, BOOL lencheck, uschar *target, int zeroval,
-  int *lenptr, int *sizeptr, uschar **error)
+rfc2047_decode2(uschar *string, BOOL lencheck, const uschar *target,
+  int zeroval, int *lenptr, int *sizeptr, uschar **error)
 {
-int ptr = 0;
 int size = Ustrlen(string);
 size_t dlen;
-uschar *dptr, *yield;
+uschar *dptr;
+gstring *yield;
 uschar *mimeword, *q1, *q2, *endword;
 
 *error = NULL;
@@ -208,7 +210,10 @@ building the result as we go. The result may be longer than the input if it is
 translated into a multibyte code such as UTF-8. That's why we use the dynamic
 string building code. */
 
-yield = store_get(++size);
+yield = store_get(sizeof(gstring) + ++size, string);
+yield->size = size;
+yield->ptr = 0;
+yield->s = US(yield + 1);
 
 while (mimeword)
   {
@@ -218,7 +223,8 @@ while (mimeword)
   #endif
 
   if (mimeword != string)
-    yield = string_catn(yield, &size, &ptr, string, mimeword - string);
+    yield = string_catn(yield, string, mimeword - string);
+/*XXX that might have to convert an untainted string to a tainted one */
 
   /* Do a charset translation if required. This is supported only on hosts
   that have the iconv() function. Translation errors set error, but carry on,
@@ -229,17 +235,11 @@ while (mimeword)
 
   #if HAVE_ICONV
   *q1 = 0;
-  if (target != NULL && strcmpic(target, mimeword+2) != 0)
-    {
-    icd = iconv_open(CS target, CS(mimeword+2));
-
-    if (icd == (iconv_t)(-1))
-      {
+  if (target && strcmpic(target, mimeword+2) != 0)
+    if ((icd = iconv_open(CS target, CS(mimeword+2))) == (iconv_t)-1)
       *error = string_sprintf("iconv_open(\"%s\", \"%s\") failed: %s%s",
         target, mimeword+2, strerror(errno),
         (errno == EINVAL)? " (maybe unsupported conversion)" : "");
-      }
-    }
   *q1 = '?';
   #endif
 
@@ -297,15 +297,12 @@ while (mimeword)
     /* Deal with zero values; convert them if requested. */
 
     if (zeroval != 0)
-      {
-      int i;
-      for (i = 0; i < tlen; i++)
+      for (int i = 0; i < tlen; i++)
         if (tptr[i] == 0) tptr[i] = zeroval;
-      }
 
     /* Add the new string onto the result */
 
-    yield = string_catn(yield, &size, &ptr, tptr, tlen);
+    yield = string_catn(yield, tptr, tlen);
     }
 
   #if HAVE_ICONV
@@ -328,11 +325,11 @@ while (mimeword)
 /* Copy the remaining characters of the string, zero-terminate it, and return
 the length as well if requested. */
 
-yield = string_cat(yield, &size, &ptr, string);
-yield[ptr] = 0;
-if (lenptr) *lenptr = ptr;
-if (sizeptr) *sizeptr = size;
-return yield;
+yield = string_cat(yield, string);
+
+if (lenptr) *lenptr = yield->ptr;
+if (sizeptr) *sizeptr = yield->size;
+return string_from_gstring(yield);
 }
 
 
@@ -340,7 +337,7 @@ return yield;
 argument. */
 
 uschar *
-rfc2047_decode(uschar *string, BOOL lencheck, uschar *target, int zeroval,
+rfc2047_decode(uschar *string, BOOL lencheck, const uschar *target, int zeroval,
   int *lenptr, uschar **error)
 {
 return rfc2047_decode2(string, lencheck, target, zeroval, lenptr, NULL, error);