How to OpenSSL decrypt smime.p7m
- by tntu
I have received an email that has no content, just a file called smime.p7m attached.
I was looking into the OpenSSL and it's smime module but I cannot figure out exactly how.
I must be doing something wrong.
I extracted the certificate chain form the p7m file.
# openssl pkcs7 -inform DER -in smime.p7m -out pkcs7.pem
# openssl pkcs7 -in pkcs7.pem -print_certs -out certs.pem
Then I tried to decrypt:
# openssl smime -decrypt -in smime.p7m -signer certs.pem -out smime.eml
No recipient certificate or key specified
And also with my server's SSL cert:
# openssl smime -decrypt -in smime.p7m -recip server.nopass.key.crt.ca.pem -out smime.eml
Error reading S/MIME message
140078540371784:error:0D0D40D1:asn1 encoding routines:SMIME_read_ASN1:no content type:asn_mime.c:447:
Can anyone shed some light on what steps I need to take to extract the email?