Enabling SSL on Ubuntu and the problem thereafter.
Recently I had to test our product on secured site, so I tried to install SSL on localhost. The config file for SSL site has been installed in /etc/apache2/sites-available. So I simply had to enable it and modify it. I first issued this to enable the SSL module:
sudo a2enmod ssl
And then I enabled the SSL config by:
sudo a2ensite default-ssl
After the above command is issued, a symlink to /etc/apache2/sites-available/default-ssl will be created and called /etc/apache2/sites-enabled/default-ssl. I edited it and uncommented the following lines:
SSLEngine on
SSLCertificateFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.nc.crt
SSLCertificateKeyFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.nc.key
The certificate (.crt file) and the key (.key file) are snakeoil, so to say, I created them using OpenSSL. The commands I used to create them are the following:
openssl genrsa -des3 -out linuxdev8.nc.key 1024
openssl req -new -key linuxdev8.nc.key -x509 -out linuxdev8.nc.crt
After that, I restarted Apache, at which point I was asked to input the key phrase:
sudo /etc/init.d/apache2 restart
And lo and behold, I can now connect to http://127.0.0.1 and https://127.0.0.1
The problem happens after Ubuntu is restarted. Apache refuses to start, and throws up the following error message instead:
Starting httpd: (98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs!
I googled for 3 days and tried all of the solutions I found, but my problem persisted. I have no clue what went wrong! I'm not a wizard when it comes to Apache directives but I guess there's something wrong somewhere in the config file. What I found to be a pseudo-solution was this:
Before restarting Ubuntu, disable the SSL site first by issuing this:
sudo a2dissite default-ssl
And then proceed to restarting Ubuntu. After computer is restarted, re-enable the SSL site and restart Apache:
sudo a2ensite default-ssl
sudo /etc/init.d/apache2 restart
That's it :)
BTW in case you wanna know my config files, the following are my /etc/apache2/ports.conf, /etc/apache2/sites-available/default, and /etc/apache2/sites-available/default-ssl, in that order:
NameVirtualHost *:80
Listen 80
# SSL name based virtual hosts are not yet supported, therefore no
# NameVirtualHost statement here
Listen 443
ServerAdmin webmaster@localhost
DocumentRoot /var/www
Options FollowSymLinks
AllowOverride None
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
ErrorLog /var/log/apache2/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /var/log/apache2/access.log combined
Alias /doc/ "/usr/share/doc/"
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
ServerAdmin webmaster@localhost
DocumentRoot /var/www
Options FollowSymLinks
AllowOverride None
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
ErrorLog /var/log/apache2/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /var/log/apache2/ssl_access.log combined
Alias /doc/ "/usr/share/doc/"
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
# SSL Engine Switch:
# Enable/Disable SSL for this virtual host.
SSLEngine on
# A self-signed (snakeoil) certificate can be created by installing
# the ssl-cert package. See
# /usr/share/doc/apache2.2-common/README.Debian.gz for more info.
# If both key and certificate are stored in the same file, only the
# SSLCertificateFile directive is needed.
SSLCertificateFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.isa.nc.crt
SSLCertificateKeyFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.isa.nc.key
# Server Certificate Chain:
# Point SSLCertificateChainFile at a file containing the
# concatenation of PEM encoded CA certificates which form the
# certificate chain for the server certificate. Alternatively
# the referenced file can be the same as SSLCertificateFile
# when the CA certificates are directly appended to the server
# certificate for convinience.
#SSLCertificateChainFile /etc/apache2/ssl.crt/server-ca.crt
# Certificate Authority (CA):
# Set the CA certificate verification path where to find CA
# certificates for client authentication or alternatively one
# huge file containing all of them (file must be PEM encoded)
# Note: Inside SSLCACertificatePath you need hash symlinks
# to point to the certificate files. Use the provided
# Makefile to update the hash symlinks after changes.
#SSLCACertificatePath /etc/ssl/certs/
#SSLCACertificateFile /etc/apache2/ssl.crt/ca-bundle.crt
# Certificate Revocation Lists (CRL):
# Set the CA revocation path where to find CA CRLs for client
# authentication or alternatively one huge file containing all
# of them (file must be PEM encoded)
# Note: Inside SSLCARevocationPath you need hash symlinks
# to point to the certificate files. Use the provided
# Makefile to update the hash symlinks after changes.
#SSLCARevocationPath /etc/apache2/ssl.crl/
#SSLCARevocationFile /etc/apache2/ssl.crl/ca-bundle.crl
# Client Authentication (Type):
# Client certificate verification type and depth. Types are
# none, optional, require and optional_no_ca. Depth is a
# number which specifies how deeply to verify the certificate
# issuer chain before deciding the certificate is not valid.
#SSLVerifyClient require
#SSLVerifyDepth 10
# Access Control:
# With SSLRequire you can do per-directory access control based
# on arbitrary complex boolean expressions containing server
# variable checks and other lookup directives. The syntax is a
# mixture between C and Perl. See the mod_ssl documentation
# for more details.
#
#SSLRequire ( %{SSL_CIPHER} !~ m/^(EXP|NULL)/ \
# and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \
# and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"} \
# and %{TIME_WDAY} >= 1 and %{TIME_WDAY} <= 5 \
# and %{TIME_HOUR} >= 8 and %{TIME_HOUR} <= 20 ) \
# or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/
#
# SSL Engine Options:
# Set various options for the SSL engine.
# o FakeBasicAuth:
# Translate the client X.509 into a Basic Authorisation. This means that
# the standard Auth/DBMAuth methods can be used for access control. The
# user name is the `one line' version of the client's X.509 certificate.
# Note that no password is obtained from the user. Every entry in the user
# file needs this password: `xxj31ZMTZzkVA'.
# o ExportCertData:
# This exports two additional environment variables: SSL_CLIENT_CERT and
# SSL_SERVER_CERT. These contain the PEM-encoded certificates of the
# server (always existing) and the client (only existing when client
# authentication is used). This can be used to import the certificates
# into CGI scripts.
# o StdEnvVars:
# This exports the standard SSL/TLS related `SSL_*' environment variables.
# Per default this exportation is switched off for performance reasons,
# because the extraction step is an expensive operation and is usually
# useless for serving static content. So one usually enables the
# exportation for CGI and SSI requests only.
# o StrictRequire:
# This denies access when "SSLRequireSSL" or "SSLRequire" applied even
# under a "Satisfy any" situation, i.e. when it applies access is denied
# and no other module can change it.
# o OptRenegotiate:
# This enables optimized SSL connection renegotiation handling when SSL
# directives are used in per-directory context.
#SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire
SSLOptions +StdEnvVars
SSLOptions +StdEnvVars
# SSL Protocol Adjustments:
# The safe and default but still SSL/TLS standard compliant shutdown
# approach is that mod_ssl sends the close notify alert but doesn't wait for
# the close notify alert from client. When you need a different shutdown
# approach you can use one of the following variables:
# o ssl-unclean-shutdown:
# This forces an unclean shutdown when the connection is closed, i.e. no
# SSL close notify alert is send or allowed to received. This violates
# the SSL/TLS standard but is needed for some brain-dead browsers. Use
# this when you receive I/O errors because of the standard approach where
# mod_ssl sends the close notify alert.
# o ssl-accurate-shutdown:
# This forces an accurate shutdown when the connection is closed, i.e. a
# SSL close notify alert is send and mod_ssl waits for the close notify
# alert of the client. This is 100% SSL/TLS standard compliant, but in
# practice often causes hanging connections with brain-dead browsers. Use
# this only for browsers where you know that their SSL implementation
# works correctly.
# Notice: Most problems of broken clients are also related to the HTTP
# keep-alive facility, so you usually additionally want to disable
# keep-alive for those clients, too. Use variable "nokeepalive" for this.
# Similarly, one has to force some clients to use HTTP/1.0 to workaround
# their broken HTTP/1.1 implementation. Use variables "downgrade-1.0" and
# "force-response-1.0" for this.
BrowserMatch ".*MSIE.*" \
nokeepalive ssl-unclean-shutdown \
downgrade-1.0 force-response-1.0
sudo a2enmod ssl
And then I enabled the SSL config by:
sudo a2ensite default-ssl
After the above command is issued, a symlink to /etc/apache2/sites-available/default-ssl will be created and called /etc/apache2/sites-enabled/default-ssl. I edited it and uncommented the following lines:
SSLEngine on
SSLCertificateFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.nc.crt
SSLCertificateKeyFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.nc.key
The certificate (.crt file) and the key (.key file) are snakeoil, so to say, I created them using OpenSSL. The commands I used to create them are the following:
openssl genrsa -des3 -out linuxdev8.nc.key 1024
openssl req -new -key linuxdev8.nc.key -x509 -out linuxdev8.nc.crt
After that, I restarted Apache, at which point I was asked to input the key phrase:
sudo /etc/init.d/apache2 restart
And lo and behold, I can now connect to http://127.0.0.1 and https://127.0.0.1
The problem happens after Ubuntu is restarted. Apache refuses to start, and throws up the following error message instead:
Starting httpd: (98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs!
I googled for 3 days and tried all of the solutions I found, but my problem persisted. I have no clue what went wrong! I'm not a wizard when it comes to Apache directives but I guess there's something wrong somewhere in the config file. What I found to be a pseudo-solution was this:
Before restarting Ubuntu, disable the SSL site first by issuing this:
sudo a2dissite default-ssl
And then proceed to restarting Ubuntu. After computer is restarted, re-enable the SSL site and restart Apache:
sudo a2ensite default-ssl
sudo /etc/init.d/apache2 restart
That's it :)
BTW in case you wanna know my config files, the following are my /etc/apache2/ports.conf, /etc/apache2/sites-available/default, and /etc/apache2/sites-available/default-ssl, in that order:
NameVirtualHost *:80
Listen 80
# SSL name based virtual hosts are not yet supported, therefore no
# NameVirtualHost statement here
Listen 443
ServerAdmin webmaster@localhost
DocumentRoot /var/www
Options FollowSymLinks
AllowOverride None
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
ErrorLog /var/log/apache2/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /var/log/apache2/access.log combined
Alias /doc/ "/usr/share/doc/"
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
ServerAdmin webmaster@localhost
DocumentRoot /var/www
Options FollowSymLinks
AllowOverride None
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
ErrorLog /var/log/apache2/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /var/log/apache2/ssl_access.log combined
Alias /doc/ "/usr/share/doc/"
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
# SSL Engine Switch:
# Enable/Disable SSL for this virtual host.
SSLEngine on
# A self-signed (snakeoil) certificate can be created by installing
# the ssl-cert package. See
# /usr/share/doc/apache2.2-common/README.Debian.gz for more info.
# If both key and certificate are stored in the same file, only the
# SSLCertificateFile directive is needed.
SSLCertificateFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.isa.nc.crt
SSLCertificateKeyFile /home/ISA.REALOBJECTS/firman/Documents/ssl/linuxdev8.isa.nc.key
# Server Certificate Chain:
# Point SSLCertificateChainFile at a file containing the
# concatenation of PEM encoded CA certificates which form the
# certificate chain for the server certificate. Alternatively
# the referenced file can be the same as SSLCertificateFile
# when the CA certificates are directly appended to the server
# certificate for convinience.
#SSLCertificateChainFile /etc/apache2/ssl.crt/server-ca.crt
# Certificate Authority (CA):
# Set the CA certificate verification path where to find CA
# certificates for client authentication or alternatively one
# huge file containing all of them (file must be PEM encoded)
# Note: Inside SSLCACertificatePath you need hash symlinks
# to point to the certificate files. Use the provided
# Makefile to update the hash symlinks after changes.
#SSLCACertificatePath /etc/ssl/certs/
#SSLCACertificateFile /etc/apache2/ssl.crt/ca-bundle.crt
# Certificate Revocation Lists (CRL):
# Set the CA revocation path where to find CA CRLs for client
# authentication or alternatively one huge file containing all
# of them (file must be PEM encoded)
# Note: Inside SSLCARevocationPath you need hash symlinks
# to point to the certificate files. Use the provided
# Makefile to update the hash symlinks after changes.
#SSLCARevocationPath /etc/apache2/ssl.crl/
#SSLCARevocationFile /etc/apache2/ssl.crl/ca-bundle.crl
# Client Authentication (Type):
# Client certificate verification type and depth. Types are
# none, optional, require and optional_no_ca. Depth is a
# number which specifies how deeply to verify the certificate
# issuer chain before deciding the certificate is not valid.
#SSLVerifyClient require
#SSLVerifyDepth 10
# Access Control:
# With SSLRequire you can do per-directory access control based
# on arbitrary complex boolean expressions containing server
# variable checks and other lookup directives. The syntax is a
# mixture between C and Perl. See the mod_ssl documentation
# for more details.
#
#SSLRequire ( %{SSL_CIPHER} !~ m/^(EXP|NULL)/ \
# and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd." \
# and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"} \
# and %{TIME_WDAY} >= 1 and %{TIME_WDAY} <= 5 \
# and %{TIME_HOUR} >= 8 and %{TIME_HOUR} <= 20 ) \
# or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/
#
# SSL Engine Options:
# Set various options for the SSL engine.
# o FakeBasicAuth:
# Translate the client X.509 into a Basic Authorisation. This means that
# the standard Auth/DBMAuth methods can be used for access control. The
# user name is the `one line' version of the client's X.509 certificate.
# Note that no password is obtained from the user. Every entry in the user
# file needs this password: `xxj31ZMTZzkVA'.
# o ExportCertData:
# This exports two additional environment variables: SSL_CLIENT_CERT and
# SSL_SERVER_CERT. These contain the PEM-encoded certificates of the
# server (always existing) and the client (only existing when client
# authentication is used). This can be used to import the certificates
# into CGI scripts.
# o StdEnvVars:
# This exports the standard SSL/TLS related `SSL_*' environment variables.
# Per default this exportation is switched off for performance reasons,
# because the extraction step is an expensive operation and is usually
# useless for serving static content. So one usually enables the
# exportation for CGI and SSI requests only.
# o StrictRequire:
# This denies access when "SSLRequireSSL" or "SSLRequire" applied even
# under a "Satisfy any" situation, i.e. when it applies access is denied
# and no other module can change it.
# o OptRenegotiate:
# This enables optimized SSL connection renegotiation handling when SSL
# directives are used in per-directory context.
#SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire
SSLOptions +StdEnvVars
SSLOptions +StdEnvVars
# SSL Protocol Adjustments:
# The safe and default but still SSL/TLS standard compliant shutdown
# approach is that mod_ssl sends the close notify alert but doesn't wait for
# the close notify alert from client. When you need a different shutdown
# approach you can use one of the following variables:
# o ssl-unclean-shutdown:
# This forces an unclean shutdown when the connection is closed, i.e. no
# SSL close notify alert is send or allowed to received. This violates
# the SSL/TLS standard but is needed for some brain-dead browsers. Use
# this when you receive I/O errors because of the standard approach where
# mod_ssl sends the close notify alert.
# o ssl-accurate-shutdown:
# This forces an accurate shutdown when the connection is closed, i.e. a
# SSL close notify alert is send and mod_ssl waits for the close notify
# alert of the client. This is 100% SSL/TLS standard compliant, but in
# practice often causes hanging connections with brain-dead browsers. Use
# this only for browsers where you know that their SSL implementation
# works correctly.
# Notice: Most problems of broken clients are also related to the HTTP
# keep-alive facility, so you usually additionally want to disable
# keep-alive for those clients, too. Use variable "nokeepalive" for this.
# Similarly, one has to force some clients to use HTTP/1.0 to workaround
# their broken HTTP/1.1 implementation. Use variables "downgrade-1.0" and
# "force-response-1.0" for this.
BrowserMatch ".*MSIE.*" \
nokeepalive ssl-unclean-shutdown \
downgrade-1.0 force-response-1.0