Provided by: botan_2.12.1-2build1_amd64 
NAME
botan - Botan command line util
OUTLINE
The botan program is a command line tool for using a broad variety of functions of the Botan library in
the shell.
All commands follow the syntax botan <command> <command-options>.
If botan is run with an unknown command, or without any command, or with the --help option, all available
commands will be printed. If a particular command is run with the --help option (like botan <command>
--help) some information about the usage of the command is printed.
Starting in version 2.9, commands that take a passphrase (such as gen_bcrypt or pkcs8) will also accept
the literal - to mean ask for the passphrase on the terminal. If supported by the operating system, echo
will be disabled while reading the passphrase.
HASH FUNCTION
hash --algo=SHA-256 --buf-size=4096 --no-fsname files
Compute the algo digest over the data in any number of files. If no files are listed on the
command line, the input source defaults to standard input. Unless the --no-fsname option is given,
the filename is printed alongside the hash, in the style of tools such as sha256sum.
PASSWORD HASH
gen_bcrypt --work-factor=12 password
Calculate the bcrypt password digest of password. work-factor is an integer between 4 and 18. A
higher work-factor value results in a more expensive hash calculation.
check_bcrypt password hash
Checks if the bcrypt hash of the passed password equals the passed hash value.
HMAC
hmac --hash=SHA-256 --buf-size=4096 --no-fsname key files
Compute the HMAC tag with the cryptographic hash function hash using the key in file key over the
data in files. files defaults to STDIN. Unless the --no-fsname option is given, the filename is
printed alongside the HMAC value.
PUBLIC KEY CRYPTOGRAPHY
keygen --algo=RSA --params= --passphrase= --pbe= --pbe-millis=300 --der-out
Generate a PKCS #8 algo private key. If der-out is passed, the pair is BER encoded. Otherwise,
PEM encoding is used. To protect the PKCS #8 formatted key, it is recommended to encrypt it with a
provided passphrase. pbe is the name of the desired encryption algorithm, which uses pbe-millis
milliseconds to derive the encryption key from the passed passphrase. Algorithm specific
parameters, as the desired bit length of an RSA key, can be passed with params.
• For RSA params specifies the bit length of the RSA modulus. It defaults to 3072.
• For DH params specifies the DH parameters. It defaults to modp/ietf/2048.
• For DSA params specifies the DSA parameters. It defaults to dsa/botan/2048.
• For EC algorithms params specifies the elliptic curve. It defaults to secp256r1.
The default pbe algorithm is "PBES2(AES-256/CBC,SHA-256)".
With PBES2 scheme, you can select any CBC or GCM mode cipher which has an OID defined (such as
3DES, Camellia, SM4, Twofish or Serpent). However most other implementations support only AES or
3DES in CBC mode. You can also choose Scrypt instead of PBKDF2, by using "Scrypt" instead of the
name of a hash function, for example "PBES2(AES-256/CBC,Scrypt)"
pkcs8 --pass-in= --pub-out --der-out --pass-out= --pbe= --pbe-millis=300 key
Open a PKCS #8 formatted key at key. If key is encrypted, the passphrase must be passed as
pass-in. It is possible to (re)encrypt the read key with the passphrase passed as pass-out. The
parameters pbe-millis and pbe work similarly to keygen.
sign --der-format --passphrase= --hash=SHA-256 --emsa= key file
Sign the data in file using the PKCS #8 private key key. If key is encrypted, the used passphrase
must be passed as pass-in. emsa specifies the signature scheme and hash the cryptographic hash
function used in the scheme.
• For RSA signatures EMSA4 (RSA-PSS) is the default scheme.
• For ECDSA and DSA emsa defaults to EMSA1 (signing the hash directly)
For ECDSA and DSA, the option --der-format outputs the signature as an ASN.1 encoded blob. Some
other tools (including openssl) default to this format.
verify --der-format --hash=SHA-256 --emsa= pubkey file signature
Verify the authenticity of the data in file with the provided signature signature and the public
key pubkey. Similarly to the signing process, emsa specifies the signature scheme and hash the
cryptographic hash function used in the scheme.
gen_dl_group --pbits=1024 --qbits=0 --seed= --type=subgroup
Generate ANSI X9.42 encoded Diffie-Hellman group parameters.
• If type=subgroup is passed, the size of the prime subgroup q is sampled as a prime of qbits
length and p is pbits long. If qbits is not passed, its length is estimated from pbits as
described in RFC 3766.
• If type=strong is passed, p is sampled as a safe prime with length pbits and the prime
subgroup has size q with pbits-1 length.
• If type=dsa is used, p and q are generated by the algorithm specified in FIPS 186-4. If the
--seed parameter is used, it allows to select the seed value, instead of one being randomly
generated. If the seed does not in fact generate a valid DSA group, the command will fail.
dl_group_info --pem name
Print raw Diffie-Hellman parameters (p,g) of the standardized DH group name. If pem is set, the
X9.42 encoded group is printed.
ec_group_info --pem name
Print raw elliptic curve domain parameters of the standardized curve name. If pem is set, the
encoded domain is printed.
pk_encrypt --aead=AES-256/GCM rsa_pubkey datafile
Encrypts datafile using the specified AEAD algorithm, under a key protected by the specified RSA
public key.
pk_decrypt rsa_privkey datafile
Decrypts a file encrypted with pk_encrypt. If the key is encrypted using a password, it will be
prompted for on the terminal.
X.509
gen_pkcs10 key CN --country= --organization= --email= --key-pass= --hash=SHA-256 --emsa=
Generate a PKCS #10 certificate signing request (CSR) using the passed PKCS #8 private key key. If
the private key is encrypted, the decryption passphrase key-pass has to be passed.*emsa* specifies
the padding scheme to be used when calculating the signature.
• For RSA keys EMSA4 (RSA-PSS) is the default scheme.
• For ECDSA, DSA, ECGDSA, ECKCDSA and GOST-34.10 keys emsa defaults to EMSA1.
gen_self_signed key CN --country= --dns= --organization= --email= --key-pass= --ca --hash=SHA-256 --emsa=
Generate a self signed X.509 certificate using the PKCS #8 private key key. If the private key is
encrypted, the decryption passphrase key-pass has to be passed. If ca is passed, the certificate
is marked for certificate authority (CA) usage. emsa specifies the padding scheme to be used when
calculating the signature.
• For RSA keys EMSA4 (RSA-PSS) is the default scheme.
• For ECDSA, DSA, ECGDSA, ECKCDSA and GOST-34.10 keys emsa defaults to EMSA1.
sign_cert --ca-key-pass= --hash=SHA-256 --duration=365 --emsa= ca_cert ca_key pkcs10_req
Create a CA signed X.509 certificate from the information contained in the PKCS #10 CSR
pkcs10_req. The CA certificate is passed as ca_cert and the respective PKCS #8 private key as
ca_key. If the private key is encrypted, the decryption passphrase ca-key-pass has to be passed.
The created certificate has a validity period of duration days. emsa specifies the padding scheme
to be used when calculating the signature. emsa defaults to the padding scheme used in the CA
certificate.
ocsp_check subject issuer
Verify an X.509 certificate against the issuers OCSP responder. Pass the certificate to validate
as subject and the CA certificate as issuer.
cert_info --fingerprint --ber file
Parse X.509 PEM certificate and display data fields. If --fingerprint is used, the certificate's
fingerprint is also printed.
cert_verify subject *ca_certs
Verify if the provided X.509 certificate subject can be successfully validated. The list of
trusted CA certificates is passed with ca_certs, which is a list of one or more certificates.
TLS SERVER/CLIENT
tls_ciphers --policy=default --version=tls1.2
Prints the list of ciphersuites that will be offered under a particular policy/version. The policy
can be any of the the strings "default", "suiteb_128", "suiteb_192", "strict", or "all" to denote
built-in policies, or it can name a file from which a policy description will be read.
tls_client host --port=443 --print-certs --policy= --tls1.0 --tls1.1 --tls1.2 --session-db=
--session-db-pass= --next-protocols= --type=tcp
Implements a testing TLS client, which connects to host via TCP or UDP on port port. The TLS
version can be set with the flags tls1.0, tls1.1 and tls1.2 of which the lowest specified version
is automatically chosen. If none of the TLS version flags is set, the latest supported version is
chosen. The client honors the TLS policy defined in the policy file and prints all certificates in
the chain, if print-certs is passed. next-protocols is a comma separated list and specifies the
protocols to advertise with Application-Layer Protocol Negotiation (ALPN).
tls_server cert key --port=443 --type=tcp --policy=
Implements a testing TLS server, which allows TLS clients to connect. Binds to either TCP or UDP
on port port. The server uses the certificate cert and the respective PKCS #8 private key key. The
server honors the TLS policy defined in the policy file.
tls_http_server cert key --port=443 --policy= --session-db --session-db-pass=
Only available if Boost.Asio support was enabled. Provides a simple HTTP server which replies to
all requests with an informational text output. The server honors the TLS policy defined in the
policy file.
tls_proxy listen_port target_host target_port server_cert server_key
Only available if Boost.Asio support was enabled. Listens on a port and forwards all connects to a
target server specified at target_host and target_port.
NUMBER THEORY
is_prime --prob=56 n
Test if the integer n is composite or prime with a Miller-Rabin primality test with (prob+2)/2
iterations.
factor n
Factor the integer n using a combination of trial division by small primes, and Pollard's Rho
algorithm. It can in reasonable time factor integers up to 110 bits or so.
gen_prime --count=1 bits
Samples count primes with a length of bits bits.
PSK DATABASE
The PSK database commands are only available if sqlite3 support was compiled in.
psk_set db db_key name psk
Using the PSK database named db and encrypting under the (hex) key db_key, save the provided psk
(also hex) under name:
$ botan psk_set psk.db deadba55 bunny f00fee
psk_get db db_key name
Get back a value saved with psk_set:
$ botan psk_get psk.db deadba55 bunny
f00fee
psk_list db db_key
List all values saved to the database under the given key:
$ botan psk_list psk.db deadba55
bunny
SECRET SHARING
Split a file into several shares.
tss_split M N data_file --id= --share-prefix=share --share-suffix=tss --hash=SHA-256
Split a file into N pieces any M of which suffices to recover the original input. The ID allows
specifying a unique key ID which may be up to 16 bytes long, this ensures that shares can be
uniquely matched. If not specified a random 16 byte value is used. A checksum can be appended to
the data to help verify correct recovery, this can be disabled using --hash=None.
tss_recover *shares
Recover some data split by tss_split. If insufficient number of shares are provided an error is
printed.
DATA ENCODING/DECODING
base64_dec file
Encode file to Base64.
base64_enc file
Decode Base64 encoded file.
hex_dec file
Encode file to Hex.
hex_enc file
Decode Hex encoded file.
MISCELLANEOUS COMMANDS
version --full
Print the version number. If option --full is provided, additional details are printed.
config info_type
Prints build information, useful for applications which want to build against the library. The
info_type argument can be any of prefix, cflags, ldflags, or libs. This is similar to information
provided by the pkg-config tool.
cpuid List available processor flags (aes_ni, SIMD extensions, ...).
asn1print file
Decode and print file with ASN.1 Basic Encoding Rules (BER).
http_get url
Retrieve resource from the passed http url.
speed --msec=500 --provider= --buf-size=1024 algos
Measures the speed of the passed algos. If no algos are passed all available speed tests are
executed. msec (in milliseconds) sets the period of measurement for each algorithm. The buf-size
option allows testing the same algorithm on one or more input sizes, for example speed
--buf-size=136,1500 AES-128/GCM tests the performance of GCM for small and large packet sizes.
rng --system --rdrand bytes
Sample bytes random bytes from the specified random number generator. If system is set, the system
RNG is used. If system is unset and rdrand is set, the hardware RDRAND instruction is used if
available. If both are unset, HMAC_DRBG is used.
cc_encrypt CC passphrase --tweak=
Encrypt the passed valid credit card number CC using FPE encryption and the passphrase passphrase.
The key is derived from the passphrase using PBKDF2 with SHA256. Due to the nature of FPE, the
ciphertext is also a credit card number with a valid checksum. tweak is public and parameterizes
the encryption function.
cc_decrypt CC passphrase --tweak=
Decrypt the passed valid ciphertext CC using FPE decryption with the passphrase passphrase and the
tweak tweak.
BOTAN(1)