From 8bc3352bee3f743c2b8f9fd9c743fca60706336c Mon Sep 17 00:00:00 2001 From: schwarze <> Date: Mon, 5 Sep 2016 10:43:42 +0000 Subject: remove CMS manuals; beck@ agress with the general idea --- src/lib/libcrypto/man/CMS_decrypt.3 | 127 ------------------------------------ 1 file changed, 127 deletions(-) delete mode 100644 src/lib/libcrypto/man/CMS_decrypt.3 (limited to 'src/lib/libcrypto/man/CMS_decrypt.3') diff --git a/src/lib/libcrypto/man/CMS_decrypt.3 b/src/lib/libcrypto/man/CMS_decrypt.3 deleted file mode 100644 index 3a34f10783..0000000000 --- a/src/lib/libcrypto/man/CMS_decrypt.3 +++ /dev/null @@ -1,127 +0,0 @@ -.Dd $Mdocdate: November 11 2015 $ -.Dt CMS_DECRYPT 3 -.Os -.Sh NAME -.Nm CMS_decrypt -.Nd decrypt content from a CMS envelopedData structure -.Sh SYNOPSIS -.In openssl/cms.h -.Ft int -.Fo CMS_decrypt -.Fa "CMS_ContentInfo *cms" -.Fa "EVP_PKEY *pkey" -.Fa "X509 *cert" -.Fa "BIO *dcont" -.Fa "BIO *out" -.Fa "unsigned int flags" -.Fc -.Sh DESCRIPTION -.Fn CMS_decrypt -extracts and decrypts the content from a CMS EnvelopedData structure. -.Fa pkey -is the private key of the recipient, -.Fa cert -is the recipient's certificate, -.Fa out -is a -.Vt BIO -to write the content to and -.Fa flags -is an optional set of flags. -.Pp -The -.Fa dcont -parameter is used in the rare case where the encrypted content is -detached. -It will normally be set to -.Dv NULL . -.Sh NOTES -.Xr OpenSSL_add_all_algorithms 3 -(or equivalent) should be called before using this function or errors -about unknown algorithms will occur. -.Pp -Although the recipients certificate is not needed to decrypt the data it -is needed to locate the appropriate (of possible several) recipients in -the CMS structure. -.Pp -If -.Fa cert -is set to -.Dv NULL , -all possible recipients are tried. -This case however is problematic. -To thwart the MMA attack (Bleichenbacher's attack on PKCS #1 v1.5 RSA -padding) all recipients are tried whether they succeed or not. -If no recipient succeeds then a random symmetric key is used to decrypt -the content: this will typically output garbage and may (but is not -guaranteed to) ultimately return a padding error only. -If -.Fn CMS_decrypt -just returned an error when all recipient encrypted keys failed to -decrypt an attacker could use this in a timing attack. -If the special flag -.Dv CMS_DEBUG_DECRYPT -is set then the above behaviour is modified and an error -.Em is -returned if no recipient encrypted key can be decrypted -.Em without -generating a random content encryption key. -Applications should use this flag with -.Sy extreme caution -especially in automated gateways as it can leave them open to attack. -.Pp -It is possible to determine the correct recipient key by other means -(for example looking them up in a database) and setting them in the CMS -structure in advance using the CMS utility functions such as -.Xr CMS_set1_pkey 3 . -In this case both -.Fa cert -and -.Fa pkey -should be set to -.Dv NULL . -.Pp -To process KEKRecipientInfo types -.Xr CMS_set1_key 3 -or -.Xr CMS_RecipientInfo_set0_key 3 -and -.Xr CMS_ReceipientInfo_decrypt 3 -should be called before -.Fn CMS_decrypt -and -.Fa cert -and -.Fa pkey -set to -.Dv NULL . -.Pp -The following flags can be passed in the -.Fa flags -parameter: -.Pp -If the -.Dv CMS_TEXT -flag is set MIME headers for type -.Sy text/plain -are deleted from the content. -If the content is not of type -.Sy text/plain -then an error is returned. -.Sh RETURN VALUES -.Fn CMS_decrypt -returns either 1 for success or 0 for failure. -The error can be obtained from -.Xr ERR_get_error 3 . -.Sh BUGS -The lack of single pass processing and the need to hold all data in -memory as mentioned in -.Xr CMS_verify 3 -also applies to -.Fn CMS_decrypt . -.Sh SEE ALSO -.Xr CMS_encrypt 3 , -.Xr ERR_get_error 3 -.Sh HISTORY -.Fn CMS_decrypt -was added to OpenSSL 0.9.8. -- cgit v1.2.3-55-g6feb