Provided by: botan_3.7.1+dfsg-2_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.
Most arguments that take a path to a file will also accept the literal - to mean the file content should
be read from STDIN instead.
All options for the command line are displayed in the summary line, and in the help output. All options
are, as the name suggests, optional, and the default values are shown. For example hash file prints the
SHA-256 of the file encoded as hex, while hash --format=base64 --algo=SHA-384 file prints the base64
encoded SHA-384 hash of the same file.
HASH FUNCTION
hash --algo=SHA-256 --buf-size=4096 --no-fsname --format=hex *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_argon2 --mem=65536 --p=1 --t=1 password
Calculate the Argon2 password digest of password. mem is the amount of memory to use in Kb, p the
parallelization parameter and t the number of iterations to use.
check_argon2 password hash
Checks if the Argon2 hash of the passed password equals the passed hash value.
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.
pbkdf_tune --algo=Scrypt --max-mem=256 --output-len=32 --check *times
Tunes the PBKDF algorithm specified with --algo= for the given times.
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.
ENCRYPTION
cipher --buf-size=4096 --decrypt --cipher= --key= --nonce= --ad=
Encrypt a given file with the specified cipher, eg "AES-256/GCM". If --decrypt is provided the file
is decrypted instead.
PUBLIC KEY CRYPTOGRAPHY
keygen --algo=RSA --params= --passphrase= --cipher= --pbkdf= --pbkdf-ms=300 --provider= --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.
If a passphrase is used, cipher specifies the name of the desired encryption algorithm (such as
"AES-256/CBC", or leave empty to use a default), and pbkdf can be used to specify the password
hashing mechanism (either a hash such as "SHA-256" to select PBKDF2, or "Scrypt").
The cipher mode must have an object identifier defined, this allows use of ciphers such as AES,
Twofish, Serpent, and SM4. Ciphers in CBC, GCM, and SIV modes are supported. However most other
implementations support only AES or 3DES in CBC mode.
If encryption is used, the parameter pbkdf-ms controls how long the password hashing function will
run 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.
pkcs8 --pass-in= --pub-out --der-out --pass-out= --cipher= --pbkdf= --pbkdf-ms=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 cipher,
pbkdf, and pbkdf-ms work similarly to keygen.
sign --der-format --passphrase= --hash=SHA-256 --padding= --provider= key file
Sign the data in file using the PKCS #8 private key key and cryptographic hash hash. If key is
encrypted, the used passphrase must be passed as pass-in.
The padding option can be used to control padding for algorithms that have divergent methods; this
mostly applies to RSA. For RSA, if the option is not specified PSS signatures are used. You can select
generating a PKCS #1 v1.5 formatted signature instead by providing --padding=PKCS1v15.
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. This option does not make sense for other algorithms
such as RSA.
The signature is formatted for your screen using base64.
verify --der-format --hash=SHA-256 --padding= 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, padding specifies the padding scheme and hash the
cryptographic hash function to use.
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.
fingerprint --no-fsname --algo=SHA-256 *keys
Calculate the public key fingerprint of the keys.
pk_workfactor --type=rsa bits
Provide an estimate of the strength of a public key based on it's size. --type= can be "rsa",
"dl" or "dl_exp".
X.509
gen_pkcs10 key CN --country= --organization= --ca --path-limit=1 --email= --dns= --ext-ku= --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= --path-limit=1 --days=365 --key-pass=
--ca --hash=SHA-256 --emsa= --der
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 --timeout=3000 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 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.
trust_roots --dn --dn-only --display
List the certificates in the system trust store.
TLS SERVER/CLIENT
The --policy= argument of the TLS commands specifies the TLS policy to use. The policy can be any of the
strings "default", "suiteb_128", "suiteb_192", "bsi", "strict", or "all" to denote built-in policies, or
it can name a file from which a policy description will be read.
tls_ciphers --policy=default --version=tls1.2
Prints the list of ciphersuites that will be offered under a particular policy/version.
tls_client host --port=443 --print-certs --policy=default --tls1.0 --tls1.1 --tls1.2
--skip-system-cert-store --trusted-cas= --session-db= --session-db-pass= --next-protocols= --type=tcp
--client-cert= --client-cert-key=
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 specified with policy 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). Pass a path to a
client certificate PEM and unencrypted PKCS8 encoded private key if client authentication is
required.
tls_server cert key --port=443 --type=tcp --policy=default --dump-traces= --max-clients=0 --socket-id=0
Implements a testing TLS server, which allows TLS clients to connect and which echos any data that
is sent to it. 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 specified with policy.
socket-id is only available on FreeBSD and sets the so_user_cookie value of the used socket.
tls_http_server cert key --port=443 --policy=default --threads=0 --max-clients=0 --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 specified with
policy.
tls_proxy listen_port target_host target_port server_cert server_key--policy=default --threads=0
--max-clients=0 --session-db= --session-db-pass=
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.
tls_client_hello --hex input
Parse and print a TLS client hello message.
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.
mod_inverse n mod
Calculates a modular inverse.
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
base32_dec file
Decode file to Base32.
base32_enc file
Encode Base32 encoded file.
base58_enc --check file
Encode file to Base58. If --check is provided Base58Check is used.
base58_dec --check file
Decode Base58 encoded file. If --check is provided Base58Check is used.
base64_dec file
Decode file to Base64.
base64_enc file
Encode Base64 encoded file.
hex_dec file
Decode file to Hex.
hex_enc file
Encode Hex encoded file.
FORWARD ERROR CORRECTION
fec_encode --suffix=fec --prefix= --output-dir= k n input
Split a given input file into n shares where k shares are required to recreate the original file.
The output shares a written to files with the file extension specified in --suffix and either the
original file name or the one specified in --prefix. The output directory is either equal to the
input file's directory or the one specified in --output-dir.
fec_decode *shares
If given enough shares, this will output the original input file's content to stdout. Otherwise an
error is printed on stderr.
fec_info share
Given a single share this will print information about the share. For instance: FEC share 4/4
with 3 needed for recovery
MISCELLANEOUS COMMANDS
version --full
Print the version number. If option --full is provided, additional details are printed.
has_command cmd
Test if the command cmd is available.
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, ...).
cpu_clock --test-duration=500
Estimate the speed of the CPU cycle counter.
asn1print --skip-context-specific --print-limit=4096 --bin-limit=2048 --max-depth=64 --pem file`
Decode and print file with ASN.1 Basic Encoding Rules (BER). If flag --pem is used, or the
filename ends in .pem, then PEM encoding is assumed. Otherwise the input is assumed to be binary
DER/BER.
http_get --redirects=1 --timeout=3000 url
Retrieve resource from the passed http url.
speed --msec=500 --format=default --ecc-groups= --provider= --buf-size=1024 --clear-cpuid=
--cpu-clock-speed=0 --cpu-clock-ratio=1.0 *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.
format can be "default", "table" or "json".
timing_test test_type --test-data-file= --test-data-dir=src/tests/data/timing --warmup-runs=1000
--measurement-runs=10000
Run various timing side channel tests.
rng --format=hex --system --rdrand --auto --entropy --drbg --drbg-seed= *bytes
Sample bytes random bytes from the specified random number generator. If system is set, the system
RNG is used. If rdrand is set, the hardware RDRAND instruction is used. If auto is set,
AutoSeeded_RNG is used, seeded with the system RNG if available or the global entropy source
otherwise. If entropy is set, AutoSeeded_RNG is used, seeded with the global entropy source. If
drbg is set, HMAC_DRBG is used seeded with drbg-seed.
entropy --truncate-at=128 source
Sample a raw entropy source.
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.
roughtime_check --raw-time chain-file
Parse and validate a Roughtime chain file.
roughtime --raw-time --chain-file=roughtime-chain --max-chain-size=128 --check-local-clock=60 --host=
--pubkey= --servers-file=
Retrieve time from a Roughtime server and store it in a chain file.
uuid Generate and print a random UUID.
compress --type=gzip --level=6 --buf-size=8192 file
Compress a given file.
decompress --buf-size=8192 file
Decompress a given compressed archive.
BOTAN(1)