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XCVII. OpenSSL Functions
This module uses the functions of OpenSSL for generation and verification
of signatures and for sealing (encrypting) and opening (decrypting)
data. OpenSSL offers many features that this module currently doesn't
support. Some of these may be added in the future.
In order to use the OpenSSL functions you need to install the OpenSSL package.
PHP between versions 4.0.5 and 4.3.1 will work with OpenSSL >= 0.9.5.
Other versions (PHP <=4.0.4pl1 and >= 4.3.2) require OpenSSL >=
0.9.6.
警告 |
You are strongly encouraged to use the most recent OpenSSL version,
otherwise your web server could be vulnerable to attack.
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To use PHP's OpenSSL support you must also compile PHP --with-openssl[=DIR].
Note to Win32 Users:
In order to enable this module on a Windows environment, you must copy
libeay32.dll from the DLL folder of the PHP/Win32 binary
package to the SYSTEM32 folder of your windows machine. (Ex:
C:\WINNT\SYSTEM32
or C:\WINDOWS\SYSTEM32)
Additionally, if you are planning to use the key generation and certificate
signing functions, you will need to install a valid openssl.cnf
on your system. As of PHP 4.3.0, we include a sample
configuration file in the openssl
folder of our win32 binary distribution. If you are using PHP 4.2.0 or
later and are missing the file, you can obtain it from
the OpenSSL home page or by
downloading the PHP 4.3.0 release and using the configuration file from
there.
Note to Win32 Users:
PHP will search for the openssl.cnf using the
following logic:
the OPENSSL_CONF environmental variable, if
set, will be used as the path (including filename) of the configuration
file.
the SSLEAY_CONF environmental variable, if
set, will be used as the path (including filename) of the configuration
file.
The file openssl.cnf will be assumed to be
found in the default certificate area, as configured at the time that
the openssl DLL was compiled. This is usually means that the default
filename is c:\usr\local\ssl\openssl.cnf.
In your installation, you need to decide whether to install the
configuration file at c:\usr\local\ssl\openssl.cnf or
whether to install it someplace else and use environmental variables
(possibly on a per-virtual-host basis) to locate the configuration file.
Note that it is possible to override the default path from the script using
the configargs of the functions that require a
configuration file.
本扩展模块在 php.ini 中未定义任何配置选项。
Quite a few of the openssl functions require a key or a certificate
parameter. PHP 4.0.5 and earlier have to use a key or certificate
resource returned by one of the openssl_get_xxx functions.
Later versions may use one of the following methods:
Certificates
An X.509 resource returned from
openssl_x509_read()
A string having the format
file://path/to/cert.pem; the named file must
contain a PEM encoded certificate
A string containing the content of a certificate, PEM encoded
Public/Private Keys
A key resource returned from
openssl_get_publickey() or
openssl_get_privatekey()
For public keys only: an X.509 resource A string having the format
file://path/to/file.pem - the named file must
contain a PEM encoded certificate/private key (it may contain both)
A string containing the content of a certificate/key, PEM encoded
For private keys, you may also use the syntax
array($key, $passphrase) where $key represents a
key specified using the file:// or textual content notation above, and
$passphrase represents a string containing the passphrase for that
private key
When calling a function that will verify a signature/certificate, the
cainfo parameter is an array containing file and
directory names that specify the locations of trusted CA files. If a
directory is specified, then it must be a correctly formed hashed
directory as the openssl command would use.
以下常量由本扩展模块定义,因此只有在本扩展模块被编译到
PHP 中,或者在运行时被动态加载后才有效。
The S/MIME functions make use of flags which are specified using a
bitfield which can include one or more of the following values:
表格 1. PKCS7 CONSTANTS Constant | Description |
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PKCS7_TEXT | Adds text/plain content type headers to encrypted/signed
message. If decrypting or verifying, it strips those headers from
the output - if the decrypted or verified message is not of MIME type
text/plain then an error will occur. | PKCS7_BINARY | Normally the input message is converted to "canonical" format
which is effectively using CR and LF as end of line: as required by
the S/MIME specification. When this options is present, no
translation occurs. This is useful when handling binary data which
may not be in MIME format. | PKCS7_NOINTERN | When verifying a message, certificates (if
any) included in the message are normally searched for the
signing certificate. With this option only the
certificates specified in the extracerts
parameter of openssl_pkcs7_verify() are
used. The supplied certificates can still be used as
untrusted CAs however.
| PKCS7_NOVERIFY | Do not verify the signers certificate of a signed
message. | PKCS7_NOCHAIN | Do not chain verification of signers certificates: that is
don't use the certificates in the signed message as untrusted CAs.
| PKCS7_NOCERTS | When signing a message the signer's certificate is normally
included - with this option it is excluded. This will reduce the
size of the signed message but the verifier must have a copy of the
signers certificate available locally (passed using the
extracerts to
openssl_pkcs7_verify() for example).
| PKCS7_NOATTR | Normally when a message is signed, a set of attributes are
included which include the signing time and the supported symmetric
algorithms. With this option they are not included.
| PKCS7_DETACHED | When signing a message, use cleartext signing with the MIME
type multipart/signed. This is the default
if you do not specify any flags to
openssl_pkcs7_sign().
If you turn this option off, the message will be signed using
opaque signing, which is more resistant to translation by mail relays
but cannot be read by mail agents that do not support S/MIME. | PKCS7_NOSIGS | Don't try and verify the signatures on a message |
注: These constants were added in 4.0.6.
peter dot mescalchin @ geemail dot com
16-May-2006 04:34
For w32 users to enable OpenSSL support. As well as copying "libeay32.dll" to the windows system32 folder you also need to copy "ssleay32.dll". The documentation above should probably be updated to note this.
This requirement was documented at the libcurl pages:
http://curl.haxx.se/libcurl/php/install.html#windows
php ~at~ wwwcrm dot komm
17-Nov-2005 12:47
If you want to use PHP for public / private key encryption jobs without needing to know the ins and outs of the Open SSL extension, the following may be of interest:
http://www.karenandalex.com/php_stuff/_class_OpenSSL.phps
This class was unavailable for a long while (server problems) but is now back up. Apologies to those who clicked through and got a 404
I hope it is useful to you...
Alex
beckman at purplecow dot com
09-Nov-2005 04:07
FreeBSD Ports tree php5-openssl uses openssl-0.9.8a. This is a problem, as if you install these two ports and attempt to open an HTTPS URL within PHP, it will fail with this error from openssl_error_string(): error:140A90A1:SSL routines:func(169):reason(161) which is SSL_R_LIBRARY_HAS_NO_CIPHERS or "library has no ciphers"
This is because the openssl library now requires you to load your ciphers manually -- all ciphers are not automatically loaded for you.
I don't believe the php5-openssl module has been updated to do this before opening an SSL connection (as of 5.0.5).
Using openssl-0.9.7i seems to work; symlinking libcrypto.so.3 to libcrypto.so.4 prevents the php5-openssl port from trying to install openssl-0.9.8a. So install openssl-stable (0.9.7i) from ports first, symlink 2nd, then install php5-openssl 3rd, and you should be OK.
matt at NOSPAMopenflowsPLEASE dot org
09-Nov-2005 02:42
The openssl functions were disabled in Debian release 3.0 (woody), but as of release 3.1 (sarge) they're available again.
greensweater
31-Aug-2005 07:21
Sorry, the code in my previous note doesn't work... the last line should read:
$csr = openssl_csr_new(array('commonName'=>'MyCSR'),$pkey,$config);
greensweater
31-Aug-2005 12:54
"You need to have a valid openssl.cnf installed for this function to operate correctly" includes most openssl functions. You can force php to find your openssl.cnf file as follows:
$config = array('config'=>'/path/to/openssl.cnf');
$pkey = openssl_pkey_new($config);
$csr = openssl_csr_new('MyCSR',$pkey,$config);
skippy zuavra net
20-Oct-2004 08:38
In case you're wondering what's a "correctly hashed" directory for the use with cainfo: it's simply a directory which contains CA public certificates in PEM/X.509 format. You can get such certificates either from the CA's website (they advertise it in visible places) or from your browser. In Explorer for instance you can click on the little yellow padlock, go to the CA entry and export it.
The only trick with the directory is that file names must be in the form "hash.#". The "hash" part is the 8-digit hex hash of the certificate, while the # part is a number which serves to differentiate certificates which give the same hash (yes, it can happen with certificates coming from the same CA). Usually # is 0, but you also can use 1, 2 and so on when having more certs with the same hash.
In order to obtain the hash of a certificate you can use the openssl command line utility like this:
openssl x509 -hash -in certfile.cer | head -1
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