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576b1d3c41
According to RFC 5321 the argument to HELO "contains the fully-qualified domain name of the SMTP client" or its IP address if no FQDN is available. BusyBox sendmail uses the NIS domain name instead which, in many cases, is likely to be the default "(none)". [vda: yes, I checked my machine and its uts.domainname was indeed "(none)"] Using the host name is more likely to satisfy the intent of the RFC while allowing the otherwise unused safe_getdomainname function to be removed. Signed-off-by: Ron Yorston <rmy@tigress.co.uk> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
53 lines
1.8 KiB
C
53 lines
1.8 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* Safe gethostname implementation for busybox
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*
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* Copyright (C) 2008 Tito Ragusa <farmatito@tiscali.it>
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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/*
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* SUSv2 guarantees that "Host names are limited to 255 bytes"
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* POSIX.1-2001 guarantees that "Host names (not including the terminating
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* null byte) are limited to HOST_NAME_MAX bytes" (64 bytes on my box).
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*
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* RFC1123 says:
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*
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* The syntax of a legal Internet host name was specified in RFC-952
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* [DNS:4]. One aspect of host name syntax is hereby changed: the
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* restriction on the first character is relaxed to allow either a
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* letter or a digit. Host software MUST support this more liberal
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* syntax.
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*
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* Host software MUST handle host names of up to 63 characters and
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* SHOULD handle host names of up to 255 characters.
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*/
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#include "libbb.h"
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#include <sys/utsname.h>
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/*
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* On success return the current malloced and NUL terminated hostname.
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* On error return malloced and NUL terminated string "?".
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* This is an illegal first character for a hostname.
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* The returned malloced string must be freed by the caller.
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*/
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char* FAST_FUNC safe_gethostname(void)
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{
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struct utsname uts;
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/* The length of the arrays in a struct utsname is unspecified;
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* the fields are terminated by a null byte.
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* Note that there is no standard that says that the hostname
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* set by sethostname(2) is the same string as the nodename field of the
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* struct returned by uname (indeed, some systems allow a 256-byte host-
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* name and an 8-byte nodename), but this is true on Linux. The same holds
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* for setdomainname(2) and the domainname field.
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*/
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/* Uname can fail only if you pass a bad pointer to it. */
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uname(&uts);
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return xstrndup(!uts.nodename[0] ? "?" : uts.nodename, sizeof(uts.nodename));
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}
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