The key, message, and signature come from Example 1.1 of:
ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip (pss-vect.txt)

(The algorithm DER was synthesized to match, and the signature enclosed in a BIT STRING).

It uses an RSA key with modulus length of 1024 bits, PSS padding,
SHA-1 as the digest, MGF1 with SHA-1, and salt length of 20.


$ openssl asn1parse -i < [PUBLIC KEY]
    0:d=0  hl=3 l= 159 cons: SEQUENCE          
    3:d=1  hl=2 l=  13 cons:  SEQUENCE          
    5:d=2  hl=2 l=   9 prim:   OBJECT            :rsaEncryption
   16:d=2  hl=2 l=   0 prim:   NULL              
   18:d=1  hl=3 l= 141 prim:  BIT STRING        
-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQClbkoOcBAXWJpRh9x+qEHRVvLsDjatUqRN/rH
mH3rZkdjFEFb/7bFitMDyg6EqiKOU3/Umq3KRy7MHzqv84LHf1c2VCAltWyuLbfXWce9jd8CSHL
I8Jwpw4lmOb/idGfEFrMLT8Ms18pKA4Thrb2TE7yLh4fINDOjP+yJJvZohNwIDAQAB
-----END PUBLIC KEY-----

$ openssl asn1parse -i < [ALGORITHM]
    0:d=0  hl=2 l=  13 cons: SEQUENCE          
    2:d=1  hl=2 l=   9 prim:  OBJECT            :rsassaPss
   13:d=1  hl=2 l=   0 cons:  SEQUENCE          
-----BEGIN ALGORITHM-----
MA0GCSqGSIb3DQEBCjAA
-----END ALGORITHM-----

-----BEGIN DATA-----
zch9oiPXht87ReC7vHITJtHuKvgGzDFUdcxvDZxm4bYjcdRc4jkuGskoRMMQEC8Vag2NUsH0xAu
jqmUJV4bLdpdXplY7qVj+0LzJhOi1F6PV9RWyO4pB50qoZ2k/kN+wYabobfqu5kRywA5fIJRXKc
vr538Gznjgj0CY+6QfnWGTwDF+i2DUtghKy0LSnjgIo7w3LYXjMRcPy/fMctC3HClmSLOk0Q9BY
pXQgHqmJcqydE/Z6o/SI8QlNwKYKL0WvgJUbxMP0uM7k20mduCK7RtzMYt1CgFn0A==
-----END DATA-----

$ openssl asn1parse -i < [SIGNATURE]
    0:d=0  hl=3 l= 129 prim: BIT STRING        
-----BEGIN SIGNATURE-----
A4GBAJB0MI+1mOlwGyKUOI5S+XH6rCtgpRRa8YXfUoe17SiH5Xzn/UTchjTkB8jg5DYLwibz7CJ
/nZ5UY46NMfUFEhXfbrucL5V5qndZijj5FLW5wb2DxOL584Kg0Ko1Qv/uZZhKYBvGnrKN6yfcoS
yCwtTD9mzVAPH/K5lNik4wy7M8
-----END SIGNATURE-----