Wildcard DNS – subdomain profile

A wildcard DNS record is a record in a DNS zone that will match requests for non-existent domain names. A wildcard DNS record is specified by  “*” as the left most label of a domain name, e.g. *.example.com.

DNS zone Entry

example.com. 86400	IN	SOA	example.com. hostmaster.example.com.
	IN	NS	ns1.example.com.
	IN	NS	ns2.example.com.
	IN	MX	10      mail.example.com.
	IN	A	192.168.1.1
mail		A	192.168.1.1
ns1		A	192.168.1.1
ns2		A	10.0.0.2
*.example.com.		A	192.168.1.1

.htaccess file:
<IfModule mod_rewrite.c>

RewriteCond %{HTTP_HOST} !^www\.example\.com
RewriteCond %{HTTP_HOST} ([^.]+)\.example\.com
RewriteRule ^$ profile.php?uid=%1

</IfModule>

Now if you want sandeepverma.example.com it will redirect to profile.php with uid=sandeepverma

Find Apache Document Root

solution: Find Apache Document Root

# grep -i 'DocumentRoot' httpd.conf

# find / -name httpd.conf
or
# locate httpd.conf

(if file here /etc/httpd/conf/httpd.conf)

# grep -i 'DocumentRoot' /etc/httpd/conf/httpd.conf

Protect file uploads via PHP

Check server-side MIME type of uploaded files

The PHP form variable $_FILES['file']['type'] does not return correct mime type, so we have to use some php functions like…….
> finfo_file()
> getimagesize()
> exif_imagetype()

if(version_compare(substr(PHP_VERSION,0,1),5) == -1)
{
$san	= finfo_open(FILEINFO_MIME);
$mime	= finfo_file($san,$FileName);
$tmpvar = explode(";", $mime);
finfo_close($san);
if($mime == "image/jpeg")
{
echo "this is jpeg";
}
else
{
echo "this is not jpeg";
}
}

One can use getID3 [http://getid3.sourceforge.net/] classes to get mime type other than images….

Don’t upload to a web accessible directory

Protect your directory to execute perticular file type by putting a .htacces file in directory

AddType text/plain .php .js .cgi

more help here:

http://www.askapache.com/htaccess/mod_rewrite-tips-and-tricks.html

domain htaccess

RewriteEngine on

RewriteCond %{HTTP_HOST} !^www\.mydomain\.com
RewriteCond %{HTTP_HOST} ([^.]+)\.mydomain\.com
RewriteRule ^(.*)$ index.php?blogger=%1

RewriteEngine on

RewriteCond %{HTTP_HOST} ^sub.domain.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.sub.domain.com$ [OR]
RewriteCond %{HTTP_HOST} ^domain.(.*)
RewriteRule ^(.*)$ http://www.domain.com/sub/$1 [R=301,L]

RewriteEngine on

# If no-www domain requested, externally redirect to www domain
rewritecond %{http_host} ^mysite\.net
RewriteRule (.*) http://www.mysite.net/$1 [R=301,L]

# If www+subdomain domain requested, externally redirect to subdomain without “www”
rewritecond %{http_host} ^www\.([^.]+)\.mysite\.net
RewriteRule (.*) http://%1.mysite.net/$1 [R=301,L]

# If subdomain+www domain requested, externally redirect to subdomain without “www”
rewritecond %{http_host} ^([^.]+)\.www\.mysite\.net
RewriteRule (.*) http://%1.mysite.net/$1 [R=301,L]

# If www domain requested, rewrite html page requests to profile.php with query string
rewritecond %{REQUEST_URI}!^/profile\.php
rewritecond %{http_host} ^www\.mysite.net
RewriteRule ^([^.]+)\.html /profile.php?page=$1 [L]

# If subdomain requested, rewrite subdomain and html page requests to profile.php with query string
rewritecond %{REQUEST_URI}!^/profile\.php
rewritecond %{http_host}!^www\.mysite\.net
rewritecond %{http_host} ^([^.]+)\.mysite\.net
RewriteRule ^([^.]+)\.html /profile.php?user=%1&page=$1 [L]

# If www domain requested, rewrite home page requests to profile.php with query string page = “home”
rewritecond %{REQUEST_URI}!^/profile\.php
rewritecond %{http_host} ^www\.mysite.net
RewriteRule ^$ /profile.php?page=home [L]

# If subdomain requested, rewrite home page requests to profile.php with query string user=subdomain & page=”home”
rewritecond %{REQUEST_URI}!^/profile\.php
rewritecond %{http_host}!^www\.mysite\.net
rewritecond %{http_host} ^([^.]+)\.mysite\.net
RewriteRule ^$ /profile.php?user=%1&page=home [L]

# If non-www domain requested, externally redirect to www domain
rewritecond %{http_host} ^mysite\.net
RewriteRule (.*) http://www.mysite.net/$1 [R=301,L]

# If www+subdomain or subdomain+www domain requested, externally redirect to subdomain without “www”
rewritecond %{http_host} ^www\.([^.]+)\.mysite\.net [OR]
rewritecond %{http_host} ^([^.]+)\.www\.mysite\.net
RewriteRule (.*) http://%1.mysite.net/$1 [R=301,L]

# if home page requested, rewrite to ‘home.html’ and pass through to following rules
RewriteRule ^$ /home.html

# If www domain requested, rewrite html page requests to profile.php with query string
rewritecond %{http_host} ^www\.mysite.net
RewriteRule ^([^.]+)\.html$ /profile.php?page=$1 [L]

# If subdomain requested, rewrite subdomain and html page requests to profile.php with query string
rewritecond %{http_host} !^www\.mysite\.net
rewritecond %{http_host} ^([^.]+)\.mysite\.net
RewriteRule ^([^.]+)\.html$ /profile.php?user=%1&page=$1 [L]