curl/lib/curl_gethostname.c
Daniel Stenberg 344a177aac
lib: remove the final strncpy() calls
wolfssl: use strcpy() as the target buffer is > 40 bytes

gethostname: return failure if the buffer is too small instead

Closes #14830
2024-09-09 13:47:38 +02:00

94 lines
2.6 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curl_setup.h"
#include "curl_gethostname.h"
/*
* Curl_gethostname() is a wrapper around gethostname() which allows
* overriding the hostname that the function would normally return.
* This capability is used by the test suite to verify exact matching
* of NTLM authentication, which exercises libcurl's MD4 and DES code
* as well as by the SMTP module when a hostname is not provided.
*
* For libcurl debug enabled builds hostname overriding takes place
* when environment variable CURL_GETHOSTNAME is set, using the value
* held by the variable to override returned hostname.
*
* Note: The function always returns the un-qualified hostname rather
* than being provider dependent.
*/
int Curl_gethostname(char * const name, GETHOSTNAME_TYPE_ARG2 namelen)
{
#ifndef HAVE_GETHOSTNAME
/* Allow compilation and return failure when unavailable */
(void) name;
(void) namelen;
return -1;
#else
int err;
char *dot;
#ifdef DEBUGBUILD
/* Override hostname when environment variable CURL_GETHOSTNAME is set */
const char *force_hostname = getenv("CURL_GETHOSTNAME");
if(force_hostname) {
if(strlen(force_hostname) < (size_t)namelen)
strcpy(name, force_hostname);
else
return 1; /* can't do it */
err = 0;
}
else {
name[0] = '\0';
err = gethostname(name, namelen);
}
#else /* DEBUGBUILD */
name[0] = '\0';
err = gethostname(name, namelen);
#endif
name[namelen - 1] = '\0';
if(err)
return err;
/* Truncate domain, leave only machine name */
dot = strchr(name, '.');
if(dot)
*dot = '\0';
return 0;
#endif
}