From 63ff32752e9a15e7f0d03b7f86ac52bd4ee15fff Mon Sep 17 00:00:00 2001 From: Peter Wu Date: Thu, 26 Sep 2013 23:05:37 +0200 Subject: [PATCH] Add support for 128-bit keys in RC2 This patch adds support for decrypting (and encrypting) using 128-bit keys using the RC2 algorithm. Signed-off-by: Peter Wu --- Hi, First of all a disclaimer, I am not a cryptographer but a computer science student. The purpose of this patch is to allow Wireshark to decrypt TLS packets using the TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 cipher suite (all cipher suites are supported, except RC2[1]). doc/gcrypt.texi was deliberately not updated as the help text might need other notes like "this algorithm should not be used as it is insecure" besides "Both 40-bit and 128-bit keys are supported". I leave updating this document up to you. Regards, Peter [1]: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=9144 --- cipher/cipher.c | 2 ++ cipher/rfc2268.c | 13 +++++++++++++ src/cipher.h | 1 + 3 files changed, 16 insertions(+) diff --git a/cipher/cipher.c b/cipher/cipher.c index 6ddd58b..3b271d6 100644 --- a/cipher/cipher.c +++ b/cipher/cipher.c @@ -87,6 +87,8 @@ static struct cipher_table_entry #if USE_RFC2268 { &_gcry_cipher_spec_rfc2268_40, &dummy_extra_spec, GCRY_CIPHER_RFC2268_40 }, + { &_gcry_cipher_spec_rfc2268_128, + &dummy_extra_spec, GCRY_CIPHER_RFC2268_128 }, #endif #if USE_SEED { &_gcry_cipher_spec_seed, diff --git a/cipher/rfc2268.c b/cipher/rfc2268.c index 130be9b..da0b9f4 100644 --- a/cipher/rfc2268.c +++ b/cipher/rfc2268.c @@ -351,8 +351,21 @@ static gcry_cipher_oid_spec_t oids_rfc2268_40[] = { NULL } }; +static gcry_cipher_oid_spec_t oids_rfc2268_128[] = + { + /* pbeWithSHAAnd128BitRC2_CBC */ + { "1.2.840.113549.1.12.1.5", GCRY_CIPHER_MODE_CBC }, + { NULL } + }; + gcry_cipher_spec_t _gcry_cipher_spec_rfc2268_40 = { "RFC2268_40", NULL, oids_rfc2268_40, RFC2268_BLOCKSIZE, 40, sizeof(RFC2268_context), do_setkey, encrypt_block, decrypt_block }; + +gcry_cipher_spec_t _gcry_cipher_spec_rfc2268_128 = { + "RFC2268_128", NULL, oids_rfc2268_128, + RFC2268_BLOCKSIZE, 128, sizeof(RFC2268_context), + do_setkey, encrypt_block, decrypt_block +}; diff --git a/src/cipher.h b/src/cipher.h index 7791083..516154f 100644 --- a/src/cipher.h +++ b/src/cipher.h @@ -193,6 +193,7 @@ extern gcry_cipher_spec_t _gcry_cipher_spec_serpent128; extern gcry_cipher_spec_t _gcry_cipher_spec_serpent192; extern gcry_cipher_spec_t _gcry_cipher_spec_serpent256; extern gcry_cipher_spec_t _gcry_cipher_spec_rfc2268_40; +extern gcry_cipher_spec_t _gcry_cipher_spec_rfc2268_128; extern gcry_cipher_spec_t _gcry_cipher_spec_seed; extern gcry_cipher_spec_t _gcry_cipher_spec_camellia128; extern gcry_cipher_spec_t _gcry_cipher_spec_camellia192; -- 1.8.4