"bf-cbc" Encryption Verification

Blowfish Cipher Tutorials - Herong's Tutorial Examples

∟OpenSSL "enc -bf-cbc" for Blowfish/CBC Encryption

∟"bf-cbc" Encryption Verification

A tutorial example is provided to verify OpenSSL 'enc -bf-cbc' command against the Blowfish CBC test vector published at www.schneier.com.

Okay, we have learned that OpenSSL "enc -bf-cbc" command can perform Blowfish encryption in CBC mode on multiple plaintext blocks. Now we needed to verify its output against existing Blowfish CBC test vectors.

When I search the Internet, I only see one published test vector for Blowfish in CBC mode at https://www.schneier.com/code/vectors.txt:

chaining mode test data
key[16]   = 0123456789ABCDEFF0E1D2C3B4A59687
iv[8]     = FEDCBA9876543210
data[29]  = "7654321 Now is the time for " (includes trailing '\0')
data[29]  = 37363534333231204E6F77206973207468652074696D6520666F722000
cbc cipher text
cipher[32]= 
   6B77B4D63006DEE605B156E27403979358DEB9E7154616D959F1652BD5FF92CC

Below is the my test to verify OpenSSL "enc -bf-cbc" cipher against the above test vector:

C:\herong>perl -e "binmode(STDOUT); print pack('H*', \
'37363534333231204E6F77206973207468652074696D6520666F722000000000')" \
   >> CBC-Test-Vector.txt

C:\herong>\local\gnuwin32\bin\openssl enc -bf-cbc -e \
   -K 0123456789ABCDEFF0E1D2C3B4A59687 -iv FEDCBA9876543210 \
   -in CBC-Test-Vector.txt -out cipher.txt -nopad -p
   
salt=0200000028263F01
key=0123456789ABCDEFF0E1D2C3B4A59687
iv =FEDCBA9876543210

C:\herong>perl -e "while (read(STDIN,$_,1)){print unpack('H*',$_);}" \
   < cipher.txt
   
6b77b4d63006dee605b156e27403979358deb9e7154616d959f1652bd5ff92cc

Congratulations! The ciphertext matches with what given in the test vector. Now we can confidently say that OpenSSL "enc -bf-cbc" command works correctly.