common: Add an easy to use DER builder.

* common/tlv-builder.c: New.
* common/tlv.c: Remove stuff only used by GnuPG 1.
(put_tlv_to_membuf, get_tlv_length): Move to ...
* common/tlv-builder.c: here.
* common/tlv.h (tlv_builder_t): New.
--

Such code should actually go into libksba and we will eventually do
that.  However, for now it is easier to keep it here.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 2 insertions, 111 deletions

diff --git a/common/tlv.c b/common/tlv.c
index 86e954a19..947464bf7 100644
--- a/common/tlv.c
+++ b/common/tlv.c
@@ -32,21 +32,13 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <assert.h>
-
-#if GNUPG_MAJOR_VERSION == 1
-#define GPG_ERR_EOF               (-1)
-#define GPG_ERR_BAD_BER           (1)  /*G10ERR_GENERAL*/
-#define GPG_ERR_INV_SEXP          (45) /*G10ERR_INV_ARG*/
-typedef int gpg_error_t;
-#define gpg_make_err(x,n) (n)
-#else
 #include <gpg-error.h>
-#endif
+
 
 #include "util.h"
 #include "tlv.h"
 
+
 static const unsigned char *
 do_find_tlv (const unsigned char *buffer, size_t length,
              int tag, size_t *nbytes, int nestlevel)
@@ -157,107 +149,6 @@ find_tlv_unchecked (const unsigned char *buffer, size_t length,
 }
 
 
-/* Write TAG of CLASS to MEMBUF.  CONSTRUCTED is a flag telling
- * whether the value is constructed.  LENGTH gives the length of the
- * value, if it is 0 undefinite length is assumed.  LENGTH is ignored
- * for the NULL tag.  TAG must be less that 0x1f.  */
-void
-put_tlv_to_membuf (membuf_t *membuf, int class, int tag,
-                   int constructed, size_t length)
-{
-  unsigned char buf[20];
-  int buflen = 0;
-  int i;
-
-  if (tag < 0x1f)
-    {
-      *buf = (class << 6) | tag;
-      if (constructed)
-        *buf |= 0x20;
-      buflen++;
-    }
-  else
-    BUG ();
-
-  if (!tag && !class)
-    buf[buflen++] = 0; /* end tag */
-  else if (tag == TAG_NULL && !class)
-    buf[buflen++] = 0; /* NULL tag */
-  else if (!length)
-    buf[buflen++] = 0x80; /* indefinite length */
-  else if (length < 128)
-    buf[buflen++] = length;
-  else
-    {
-      /* If we know the sizeof a size_t we could support larger
-       * objects - however this is pretty ridiculous */
-      i = (length <= 0xff ? 1:
-           length <= 0xffff ? 2:
-           length <= 0xffffff ? 3: 4);
-
-      buf[buflen++] = (0x80 | i);
-      if (i > 3)
-        buf[buflen++] = length >> 24;
-      if (i > 2)
-        buf[buflen++] = length >> 16;
-      if (i > 1)
-        buf[buflen++] = length >> 8;
-      buf[buflen++] = length;
-    }
-
-  put_membuf (membuf, buf, buflen);
-}
-
-
-/* Return the length of the to be constructed TLV.  CONSTRUCTED is a
- * flag telling whether the value is constructed.  LENGTH gives the
- * length of the value, if it is 0 undefinite length is assumed.
- * LENGTH is ignored for the NULL tag.  TAG must be less that 0x1f.  */
-size_t
-get_tlv_length (int class, int tag, int constructed, size_t length)
-{
-  size_t buflen = 0;
-  int i;
-
-  (void)constructed;  /* Not used, but passed for uniformity of such calls.  */
-
-  if (tag < 0x1f)
-    {
-      buflen++;
-    }
-  else
-    {
-      buflen++; /* assume one and let the actual write function bail out */
-    }
-
-  if (!tag && !class)
-    buflen++; /* end tag */
-  else if (tag == TAG_NULL && !class)
-    buflen++; /* NULL tag */
-  else if (!length)
-    buflen++; /* indefinite length */
-  else if (length < 128)
-    buflen++;
-  else
-    {
-      i = (length <= 0xff ? 1:
-           length <= 0xffff ? 2:
-           length <= 0xffffff ? 3: 4);
-
-      buflen++;
-      if (i > 3)
-        buflen++;
-      if (i > 2)
-        buflen++;
-      if (i > 1)
-        buflen++;
-      buflen++;
-    }
-
-  return buflen + length;
-}
-
-
 /* ASN.1 BER parser: Parse BUFFER of length SIZE and return the tag
    and the length part from the TLV triplet.  Update BUFFER and SIZE
    on success. */