As someone already mentioned in the previous comment it didn't work for me until I passed in that hidden sixth argument and also explicitly add the mime header into the $in_filename contents. (I am using PHP5)
$data = file_get_contents($in_filename);
file_put_contents($in_filename, "MIME-Version: 1.0\nContent-Disposition: attachment; filename=\"smime.p7m\"\nContent-Type: app
lication/x-pkcs7-mime; name=\"smime.p7m\"\nContent-Transfer-Encoding: base64\n\n$data");
openssl_pkcs7_verify("$in_filename",
$flag,
"$out_filename.cert",
array($path_to_cert),
$path_to_cert,
$out_filename));
openssl_pkcs7_verify
Description
mixed openssl_pkcs7_verify ( string filename, int flags [, string outfilename [, array cainfo [, string extracerts]]] )openssl_pkcs7_verify() reads the S/MIME message contained in the filename specified by filename and examines the digital signature. It returns TRUE if the signature is verified, FALSE if it is not correct (the message has been tampered with, or the signing certificate is invalid), or -1 on error.
flags can be used to affect how the signature is verified - see PKCS7 constants for more information.
If the outfilename is specified, it should be a string holding the name of a file into which the certificates of the persons that signed the messages will be stored in PEM format.
If the cainfo is specified, it should hold information about the trusted CA certificates to use in the verification process - see certificate verification for more information about this parameter.
If the extracerts is specified, it is the filename of a file containing a bunch of certificates to use as untrusted CAs.
add a note
User Contributed Notes
hema
30-Sep-2006 05:39
30-Sep-2006 05:39
14-Feb-2006 08:59
There is a hidden sixth argument: string pointing to a file where the contents of the signed message should be saved.
It is very important for verifying signed and encrypted messages from MS Outlook which uses opaque signing. After decrypting of message you will get another MIME envelope like this:
MIME-Version: 1.0
Content-Disposition: attachment; filename="smime.p7m"
Content-Type: application/x-pkcs7-mime; smime-type=signed-data; name="smime.p7m"
Content-Transfer-Encoding: base64
MIIM/QYJ...
Even if you use base64_decode() you will not get decrypted message but PKCS #7 object.
BTW: How to create opaque signed message like from MS Outlook? Switch off PKCS7_DETACHED flag (the last 0 does it):
openssl_pkcs7_sign(
"full_path_to_message_file",
"full_path_where_to_store_signed_message_file",
"file://full_path_to_my_public_certificate.pem",
array("file://full_path_to_my_private_key.pem", "password"),
array(),
0
);