view libtomcrypt/src/pk/asn1/der/printable_string/der_decode_printable_string.c @ 1902:4a6725ac957c

Revert "Don't include sk keys at all in KEX list" This reverts git commit f972813ecdc7bb981d25b5a63638bd158f1c8e72. The sk algorithms need to remain in the sigalgs list so that they are included in the server-sig-algs ext-info message sent by the server. RFC8308 for server-sig-algs requires that all algorithms are listed (though OpenSSH client 8.4p1 tested doesn't require that)
author Matt Johnston <matt@ucc.asn.au>
date Thu, 24 Mar 2022 13:42:08 +0800
parents 6dba84798cd5
children
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/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 */
#include "tomcrypt.h"

/**
  @file der_decode_printable_string.c
  ASN.1 DER, encode a printable STRING, Tom St Denis
*/


#ifdef LTC_DER

/**
  Store a printable STRING
  @param in      The DER encoded printable STRING
  @param inlen   The size of the DER printable STRING
  @param out     [out] The array of octets stored (one per char)
  @param outlen  [in/out] The number of octets stored
  @return CRYPT_OK if successful
*/
int der_decode_printable_string(const unsigned char *in, unsigned long inlen,
                                unsigned char *out, unsigned long *outlen)
{
   unsigned long x, y, len;
   int           t;

   LTC_ARGCHK(in     != NULL);
   LTC_ARGCHK(out    != NULL);
   LTC_ARGCHK(outlen != NULL);

   /* must have header at least */
   if (inlen < 2) {
      return CRYPT_INVALID_PACKET;
   }

   /* check for 0x13 */
   if ((in[0] & 0x1F) != 0x13) {
      return CRYPT_INVALID_PACKET;
   }
   x = 1;

   /* decode the length */
   if (in[x] & 0x80) {
      /* valid # of bytes in length are 1,2,3 */
      y = in[x] & 0x7F;
      if ((y == 0) || (y > 3) || ((x + y) > inlen)) {
         return CRYPT_INVALID_PACKET;
      }

      /* read the length in */
      len = 0;
      ++x;
      while (y--) {
         len = (len << 8) | in[x++];
      }
   } else {
      len = in[x++] & 0x7F;
   }

   /* is it too long? */
   if (len > *outlen) {
      *outlen = len;
      return CRYPT_BUFFER_OVERFLOW;
   }

   if (len + x > inlen) {
      return CRYPT_INVALID_PACKET;
   }

   /* read the data */
   for (y = 0; y < len; y++) {
       t = der_printable_value_decode(in[x++]);
       if (t == -1) {
           return CRYPT_INVALID_ARG;
       }
       out[y] = t;
   }

   *outlen = y;

   return CRYPT_OK;
}

#endif

/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */