1 files changed, 60 insertions, 8 deletions

diff --git a/linden/indra/llmessage/llblowfishcipher.cpp b/linden/indra/llmessage/llblowfishcipher.cpp
index f24d103..3eebfad 100644
--- a/linden/indra/llmessage/llblowfishcipher.cpp
+++ b/linden/indra/llmessage/llblowfishcipher.cpp
@@ -73,13 +73,13 @@ U32 LLBlowfishCipher::encrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
     unsigned char initial_vector[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
         EVP_EncryptInit_ex(&context, NULL, NULL, mSecret, initial_vector);
 
-    int blocksize = EVP_CIPHER_CTX_block_size(&context);
-    int keylen = EVP_CIPHER_CTX_key_length(&context);
-    int iv_length = EVP_CIPHER_CTX_iv_length(&context);
-    lldebugs << "LLBlowfishCipher blocksize " << blocksize
-                << " keylen " << keylen
-                << " iv_len " << iv_length
-                << llendl;
+//    int blocksize = EVP_CIPHER_CTX_block_size(&context);
+//    int keylen = EVP_CIPHER_CTX_key_length(&context);
+//    int iv_length = EVP_CIPHER_CTX_iv_length(&context);
+//    lldebugs << "LLBlowfishCipher blocksize " << blocksize
+//              << " keylen " << keylen
+//              << " iv_len " << iv_length
+//              << llendl;
 
         int output_len = 0;
         int temp_len = 0;
@@ -113,7 +113,59 @@ ERROR:
 // virtual
 U32 LLBlowfishCipher::decrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
 {
-        llerrs << "LLBlowfishCipher decrypt unsupported" << llendl;
+        if (!src || !src_len || !dst || !dst_len) return 0;
+        if (src_len > dst_len) return 0;
+
+        // OpenSSL uses "cipher contexts" to hold encryption parameters.
+    EVP_CIPHER_CTX context;
+    EVP_CIPHER_CTX_init(&context);
+
+        // We want a blowfish cyclic block chain cipher, but need to set 
+        // the key length before we pass in a key, so call EncryptInit 
+        // first with NULLs.
+        EVP_DecryptInit_ex(&context, EVP_bf_cbc(), NULL, NULL, NULL);
+        EVP_CIPHER_CTX_set_key_length(&context, (int)mSecretSize);
+        
+        // Complete initialization.  Per EVP_EncryptInit man page, the
+        // cipher pointer must be NULL.  Apparently initial_vector must
+        // be 8 bytes for blowfish, as this is the block size.
+    unsigned char initial_vector[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+        EVP_DecryptInit_ex(&context, NULL, NULL, mSecret, initial_vector);
+
+//    int blocksize = EVP_CIPHER_CTX_block_size(&context);
+//    int keylen = EVP_CIPHER_CTX_key_length(&context);
+//    int iv_length = EVP_CIPHER_CTX_iv_length(&context);
+//    lldebugs << "LLBlowfishCipher blocksize " << blocksize
+//              << " keylen " << keylen
+//              << " iv_len " << iv_length
+//              << llendl;
+
+        int output_len = 0;
+        int temp_len = 0;
+        if (!EVP_DecryptUpdate(&context,
+                        dst,
+                        &output_len,
+                        src,
+                        src_len))
+        {
+                llwarns << "LLBlowfishCipher::decrypt EVP_DecryptUpdate failure" << llendl;
+                goto ERROR;
+        }
+
+        // There may be some final data left to decrypt if the input is
+        // not an exact multiple of the block size.
+        if (!EVP_DecryptFinal_ex(&context, (unsigned char*)(dst + output_len), &temp_len))
+        {
+                llwarns << "LLBlowfishCipher::decrypt EVP_DecryptFinal failure" << llendl;
+                goto ERROR;
+        }
+        output_len += temp_len;
+
+        EVP_CIPHER_CTX_cleanup(&context);
+        return output_len;
+
+ERROR:
+        EVP_CIPHER_CTX_cleanup(&context);
         return 0;
 }