PKCS7_sign
LCRYPTO_USED(PKCS7_sign);
LCRYPTO_ALIAS(PKCS7_sign);
PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
p7 = PKCS7_sign(cert, pkey, certs, bio_content, 0);
p7 = PKCS7_sign(NULL, NULL, NULL, bio_content, flags);
p7 = PKCS7_sign(NULL, NULL, other, in,