Re: Masking the password entered by the user

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From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups	comp.lang.c
Subject	Re: Masking the password entered by the user
Date	Tue, 07 Feb 2017 19:39:17 +0000
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Alla _ <modelling.data@gmail.com> writes:

> char *user_pass()
> {
>     char *password = NULL;
>     if(!(password = buff_alloc()))

I'd initialise with the correct value.  Don't make setting things to
zero or NULL a knee-jerk reaction!

And I prefer to be positive:

  char *password = buff_alloc();
  if (password) {
     ... read in the characters ...
  }
  return password;

but there are two sides to this.

>         return NULL;
>     int c;
>     int i = 0;
>     
>     while( (c = getchar()) != EOF && (c != '\n' && c != '\r'))
>         password[i++] = c;

Buffer overflow.

>     if (c == '\n')
>         password[i] = '\0';

You always want to return a string so there should be nothing special
about \n.

>     return password;
> }

-- 
Ben.

Thread

Masking the password entered by the user Alla _ <modelling.data@gmail.com> - 2017-02-07 09:19 -0800
  Re: Masking the password entered by the user Keith Thompson <kst-u@mib.org> - 2017-02-07 09:34 -0800
  Re: Masking the password entered by the user "James R. Kuyper" <jameskuyper@verizon.net> - 2017-02-07 12:54 -0500
    Re: Masking the password entered by the user Alla _ <modelling.data@gmail.com> - 2017-02-07 10:21 -0800
      Re: Masking the password entered by the user Keith Thompson <kst-u@mib.org> - 2017-02-07 12:16 -0800
  Re: Masking the password entered by the user luser droog <luser.droog@gmail.com> - 2017-02-07 11:10 -0800
  Re: Masking the password entered by the user Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-07 19:39 +0000
    Re: Masking the password entered by the user Alla _ <modelling.data@gmail.com> - 2017-02-07 12:21 -0800

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