When are trying to decrypt a PGP file we are facing the below issue.
gpg: protection algorithm 1 (IDEA) is not supported
gpg: encrypted with 1024-bit RSA key, created 2005-02-04
gpg: public key decryption failed: Invalid cipher algorithm
gpg: decryption failed: No secret key
The patents on IDEA was one of the major reasons to write GnuPG and thus to
avoid IDEA. Meanwhile the IDEA patent expired and Libgcrypt supports it. Thus
if you update to a decent version of Libgcrypt this works for you. Libgcrypt
must be >= 1.6.0. You may also use GnuPG 1.4.14 which also includes IDEA.
Hi Werner,
Thnaks very much for the support.
The version we are using is as below
gpg --version
gpg (GnuPG) 2.0.14
libgcrypt 1.4.5
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Home: ~/.gnupg
Supported algorithms:
Pubkey: RSA, ELG, DSA
Cipher: 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH, CAMELLIA128,
CAMELLIA192, CAMELLIA256
Hash: MD5, SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2
If we update our libgcrypt 1.4.5 to 1.6.0 will it work for us to decrypt the
PGP file which is encrypted with idea algorithm
That is a very old gnupg version - You better update GnuPG to 2.0.27 and
Libgcrypt to 1.6.3.