SSL_CIPHER_get_name, SSL_CIPHER_get_bits, SSL_CIPHER_get_version, SSL_CIPHER_description — get SSL_CIPHER properties
char *SSL_CIPHER_get_name(SSL_CIPHER *cipher);
*cipher, int *alg_bits);
char *SSL_CIPHER_description(SSL_CIPHER *cipher,
char *buf, int size);
SSL_CIPHER_get_name() returns a pointer to the name of cipher.
If the argument is the NULL pointer, a pointer to the constant value
"NONE" is returned.
SSL_CIPHER_get_bits() returns the number of secret bits used
for cipher. If alg_bits is not NULL, it contains the number of bits
processed by the chosen algorithm. If cipher is NULL, 0 is returned.
SSL_CIPHER_get_version() returns the protocol version for
cipher, currently "SSLv2", "SSLv3", or "TLSv1". If cipher is NULL,
"(NONE)" is returned.
SSL_CIPHER_description() returns a textual description of
the cipher used into the buffer buf of length len provided. len
must be at least 128 bytes, otherwise a pointer to the the string
"Buffer too small" is returned. If buf is NULL, a buffer of 128
bytes is allocated using OPENSSL_malloc(). If the allocation fails,
a pointer to the string "OPENSSL_malloc Error" is returned.
The number of bits processed can be different from the secret
bits. An export cipher like e.g. EXP-RC4-MD5 has only 40 secret
bits. The algorithm does use the full 128 bits (which would be returned
for alg_bits), of which however 88bits are fixed. The search space
is hence only 40 bits.
The string returned by SSL_CIPHER_description() in case of
success consists of cleartext information separated by one or more
blanks in the following sequence:
Textual representation of the cipher name.
Protocol version: SSLv2, SSLv3. The TLSv1 ciphers are flagged
Key exchange method: RSA (for export ciphers as RSA(512) or
RSA(1024)), DH (for export ciphers as DH(512) or DH(1024)), DH/RSA,
Authentication method: RSA, DSS, DH, None. None is the representation
of anonymous ciphers.
Enc=<symmetric encryption method>
Encryption method with number of secret bits: DES(40), DES(56),
3DES(168), RC4(40), RC4(56), RC4(64), RC4(128), RC2(40), RC2(56),
RC2(128), IDEA(128), Fortezza, None.
Mac=<message authentication code>
Message digest: MD5, SHA1.
If the cipher is flagged exportable with respect to old US
crypto regulations, the word "export" is printed.
Some examples for the output of SSL_CIPHER_description():
EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1
EDH-DSS-DES-CBC3-SHA SSLv3 Kx=DH Au=DSS Enc=3DES(168) Mac=SHA1
RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5
EXP-RC4-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export
If SSL_CIPHER_description() is called with cipher being NULL,
the library crashes.
If SSL_CIPHER_description() cannot handle a built-in cipher,
the according description of the cipher property is unknown. This
case should not occur.
ssl(3), SSL_get_current_cipher(3), SSL_get_ciphers(3), ciphers(1)