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.
 */

/* The implementation is based on:
 * chacha-ref.c version 20080118
 * Public domain from D. J. Bernstein
 */

#include "tomcrypt.h"

#ifdef LTC_CHACHA

/**
  Set IV + counter data to the ChaCha state
  @param st      The ChaCha20 state
  @param iv      The IV data to add
  @param ivlen   The length of the IV (must be 8)
  @param counter 64bit (unsigned) initial counter value
  @return CRYPT_OK on success
 */
int chacha_ivctr64(chacha_state *st, const unsigned char *iv, unsigned long ivlen, ulong64 counter)
{
   LTC_ARGCHK(st != NULL);
   LTC_ARGCHK(iv != NULL);
   /* 64bit IV + 64bit counter */
   LTC_ARGCHK(ivlen == 8);

   st->input[12] = (ulong32)(counter & 0xFFFFFFFF);
   st->input[13] = (ulong32)(counter >> 32);
   LOAD32L(st->input[14], iv + 0);
   LOAD32L(st->input[15], iv + 4);
   st->ksleft = 0;
   st->ivlen = ivlen;
   return CRYPT_OK;
}

#endif

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