fix some gcc warnings (#73) * tweak string size fix gcc8 warnings ``` svr-agentfwd.c: In function 'bindagent': svr-agentfwd.c:254:53: warning: '%s' directive output may be truncated writing up to 107 bytes into a region of size between 0 and 107 [-Wformat-truncation=] snprintf(addr.sun_path, sizeof(addr.sun_path), "%s/%s", path, sockfile); ^~ ~~~~~~~~ svr-agentfwd.c:254:2: note: 'snprintf' output between 2 and 216 bytes into a destination of size 108 snprintf(addr.sun_path, sizeof(addr.sun_path), "%s/%s", path, sockfile); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ``` * cleanup signed/unsigned comparison fix gcc8 warnings ``` scp.c: In function 'do_local_cmd': scp.c:132:17: warning: comparison of integer expressions of different signedness: 'u_int' {aka 'unsigned int'} and 'int' [-Wsign-compare] for (i = 0; i < a->num; i++) ^ scpmisc.c: In function 'addargs': scpmisc.c:161:25: warning: comparison of integer expressions of different signedness: 'int' and 'u_int' {aka 'unsigned int'} [-Wsign-compare] } else if (args->num+2 >= nalloc) ^~ scpmisc.c: In function 'replacearg': scpmisc.c:183:12: warning: comparison of integer expressions of different signedness: 'u_int' {aka 'unsigned int'} and 'int' [-Wsign-compare] if (which >= args->num) ^~ scpmisc.c: In function 'freeargs': scpmisc.c:196:17: warning: comparison of integer expressions of different signedness: 'u_int' {aka 'unsigned int'} and 'int' [-Wsign-compare] for (i = 0; i < args->num; i++) ^ ``` see https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/misc.h.diff?r1=1.16&r2=1.17

/* 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"

#ifdef LTC_MDH

/**
  Check DH public key (INTERNAL ONLY, not part of public API)
  @param key    The key you wish to test
  @return CRYPT_OK if successful
*/
int dh_check_pubkey(dh_key *key)
{
   void *p_minus1;
   ltc_mp_digit digit;
   int i, digit_count, bits_set = 0, err;

   LTC_ARGCHK(key != NULL);

   if ((err = mp_init(&p_minus1)) != CRYPT_OK) {
      return err;
   }

   /* avoid: y <= 1 OR y >= p-1 */
   if ((err = mp_sub_d(key->prime, 1, p_minus1)) != CRYPT_OK) {
      goto error;
   }
   if (mp_cmp(key->y, p_minus1) != LTC_MP_LT || mp_cmp_d(key->y, 1) != LTC_MP_GT) {
      err = CRYPT_INVALID_ARG;
      goto error;
   }

   /* public key must have more than one bit set */
   digit_count = mp_get_digit_count(key->y);
   for (i = 0; i < digit_count && bits_set < 2; i++) {
      digit = mp_get_digit(key->y, i);
      while (digit > 0) {
         if (digit & 1) bits_set++;
         digit >>= 1;
      }
   }
   if (bits_set > 1) {
      err = CRYPT_OK;
   }
   else {
      err = CRYPT_INVALID_ARG;
   }

error:
   mp_clear(p_minus1);
   return err;
}

#endif /* LTC_MDH */

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