ddnnsssseecc--kkeeyyggeenn generates keys for DNSSEC (Secure DNS), as defined in RFC 2535 and RFC 4034. It can also generate keys for use with TSIG (Transaction Signatures) as defined in RFC 2845, or TKEY (Transaction Key) as defined in RFC 2930.
The nnaammee of the key is specified on the command line. For DNSSEC keys, this must match the name of the zone for which the key is being generated.
-a _a_l_g_o_r_i_t_h_m
Selects the cryptographic algorithm. For DNSSEC keys, the value of
aallggoorriitthhmm
must be one of RSAMD5, RSASHA1, DSA, NSEC3RSASHA1, NSEC3DSA, RSASHA256 or RSASHA512. For TSIG/TKEY, the value must be DH (Diffie Hellman), HMAC-MD5, HMAC-SHA1, HMAC-SHA224, HMAC-SHA256, HMAC-SHA384, or HMAC-SHA512. These values are case insensitive.
If no algorithm is specified, then RSASHA1 will be used by default, unless the
--33
option is specified, in which case NSEC3RSASHA1 will be used instead. (If
--33
is used and an algorithm is specified, that algorithm will be checked for compatibility with NSEC3.)
Note 1: that for DNSSEC, RSASHA1 is a mandatory to implement algorithm, and DSA is recommended. For TSIG, HMAC-MD5 is mandatory.
Note 2: DH, HMAC-MD5, and HMAC-SHA1 through HMAC-SHA512 automatically set the -T KEY option.
-b _k_e_y_s_i_z_e
Specifies the number of bits in the key. The choice of key size depends on the algorithm used. RSA keys must be between 512 and 2048 bits. Diffie Hellman keys must be between 128 and 4096 bits. DSA keys must be between 512 and 1024 bits and an exact multiple of 64. HMAC keys must be between 1 and 512 bits.
The key size does not need to be specified if using a default algorithm. The default key size is 1024 bits for zone signing keys (ZSK's) and 2048 bits for key signing keys (KSK's, generated with
--ff KKSSKK). However, if an algorithm is explicitly specified with the
--aa, then there is no default key size, and the
--bb
must be used.
-n _n_a_m_e_t_y_p_e Specifies the owner type of the key. The value of nnaammeettyyppee must either be ZONE (for a DNSSEC zone key (KEY/DNSKEY)), HOST or ENTITY (for a key associated with a host (KEY)), USER (for a key associated with a user(KEY)) or OTHER (DNSKEY). These values are case insensitive. Defaults to ZONE for DNSKEY generation.
-3 Use an NSEC3-capable algorithm to generate a DNSSEC key. If this option is used and no algorithm is explicitly set on the command line, NSEC3RSASHA1 will be used by default. Note that RSASHA256 and RSASHA512 algorithms are NSEC3-capable.
-C Compatibility mode: generates an old-style key, without any metadata. By default, ddnnsssseecc--kkeeyyggeenn will include the key's creation date in the metadata stored with the private key, and other dates may be set there as well (publication date, activation date, etc). Keys that include this data may be incompatible with older versions of BIND; the --CC option suppresses them.
-c _c_l_a_s_s Indicates that the DNS record containing the key should have the specified class. If not specified, class IN is used.
-E _e_n_g_i_n_e Uses a crypto hardware (OpenSSL engine) for random number and, when supported, key generation. When compiled with PKCS#11 support it defaults to pkcs11; the empty name resets it to no engine.
-e If generating an RSAMD5/RSASHA1 key, use a large exponent.
-f _f_l_a_g Set the specified flag in the flag field of the KEY/DNSKEY record. The only recognized flags are KSK (Key Signing Key) and REVOKE.
-G Generate a key, but do not publish it or sign with it. This option is incompatible with -P and -A.
-g _g_e_n_e_r_a_t_o_r If generating a Diffie Hellman key, use this generator. Allowed values are 2 and 5. If no generator is specified, a known prime from RFC 2539 will be used if possible; otherwise the default is 2.
-h Prints a short summary of the options and arguments to ddnnsssseecc--kkeeyyggeenn.
-K _d_i_r_e_c_t_o_r_y Sets the directory in which the key files are to be written.
-k Deprecated in favor of -T KEY.
-p _p_r_o_t_o_c_o_l Sets the protocol value for the generated key. The protocol is a number between 0 and 255. The default is 3 (DNSSEC). Other possible values for this argument are listed in RFC 2535 and its successors.
-q Quiet mode: Suppresses unnecessary output, including progress indication. Without this option, when ddnnsssseecc--kkeeyyggeenn is run interactively to generate an RSA or DSA key pair, it will print a string of symbols to _s_t_d_e_r_r indicating the progress of the key generation. A '.' indicates that a random number has been found which passed an initial sieve test; '+' means a number has passed a single round of the Miller-Rabin primality test; a space means that the number has passed all the tests and is a satisfactory key.
-r _r_a_n_d_o_m_d_e_v Specifies the source of randomness. If the operating system does not provide a _/_d_e_v_/_r_a_n_d_o_m or equivalent device, the default source of randomness is keyboard input. _r_a_n_d_o_m_d_e_v specifies the name of a character device or file containing random data to be used instead of the default. The special value _k_e_y_b_o_a_r_d indicates that keyboard input should be used.
-S _k_e_y Create a new key which is an explicit successor to an existing key. The name, algorithm, size, and type of the key will be set to match the existing key. The activation date of the new key will be set to the inactivation date of the existing one. The publication date will be set to the activation date minus the prepublication interval, which defaults to 30 days.
-s _s_t_r_e_n_g_t_h Specifies the strength value of the key. The strength is a number between 0 and 15, and currently has no defined purpose in DNSSEC.
-T _r_r_t_y_p_e Specifies the resource record type to use for the key. rrrrttyyppee must be either DNSKEY or KEY. The default is DNSKEY when using a DNSSEC algorithm, but it can be overridden to KEY for use with SIG(0). Using any TSIG algorithm (HMAC-* or DH) forces this option to KEY.
-t _t_y_p_e Indicates the use of the key. ttyyppee must be one of AUTHCONF, NOAUTHCONF, NOAUTH, or NOCONF. The default is AUTHCONF. AUTH refers to the ability to authenticate data, and CONF the ability to encrypt data.
-v _l_e_v_e_l Sets the debugging level.
Dates can be expressed in the format YYYYMMDD or YYYYMMDDHHMMSS. If the argument begins with a '+' or '-', it is interpreted as an offset from the present time. For convenience, if such an offset is followed by one of the suffixes 'y', 'mo', 'w', 'd', 'h', or 'mi', then the offset is computed in years (defined as 365 24-hour days, ignoring leap years), months (defined as 30 24-hour days), weeks, days, hours, or minutes, respectively. Without a suffix, the offset is computed in seconds.
-P _d_a_t_e_/_o_f_f_s_e_t Sets the date on which a key is to be published to the zone. After that date, the key will be included in the zone but will not be used to sign it. If not set, and if the -G option has not been used, the default is "now".
-A _d_a_t_e_/_o_f_f_s_e_t Sets the date on which the key is to be activated. After that date, the key will be included in the zone and used to sign it. If not set, and if the -G option has not been used, the default is "now".
-R _d_a_t_e_/_o_f_f_s_e_t Sets the date on which the key is to be revoked. After that date, the key will be flagged as revoked. It will be included in the zone and will be used to sign it.
-I _d_a_t_e_/_o_f_f_s_e_t Sets the date on which the key is to be retired. After that date, the key will still be included in the zone, but it will not be used to sign it.
-D _d_a_t_e_/_o_f_f_s_e_t Sets the date on which the key is to be deleted. After that date, the key will no longer be included in the zone. (It may remain in the key repository, however.)
-i _i_n_t_e_r_v_a_l
Sets the prepublication interval for a key. If set, then the publication and activation dates must be separated by at least this much time. If the activation date is specified but the publication date isn't, then the publication date will default to this much time before the activation date; conversely, if the publication date is specified but activation date isn't, then activation will be set to this much time after publication.
If the key is being created as an explicit successor to another key, then the default prepublication interval is 30 days; otherwise it is zero.
As with date offsets, if the argument is followed by one of the suffixes 'y', 'mo', 'w', 'd', 'h', or 'mi', then the interval is measured in years, months, weeks, days, hours, or minutes, respectively. Without a suffix, the interval is measured in seconds.
When ddnnsssseecc--kkeeyyggeenn completes successfully, it prints a string of the form _K_n_n_n_n_._+_a_a_a_+_i_i_i_i_i to the standard output. This is an identification string for the key it has generated.
ddnnsssseecc--kkeeyyggeenn creates two files, with names based on the printed string. _K_n_n_n_n_._+_a_a_a_+_i_i_i_i_i_._k_e_y contains the public key, and _K_n_n_n_n_._+_a_a_a_+_i_i_i_i_i_._p_r_i_v_a_t_e contains the private key.
The _._k_e_y file contains a DNS KEY record that can be inserted into a zone file (directly or with a $INCLUDE statement).
The _._p_r_i_v_a_t_e file contains algorithm-specific fields. For obvious security reasons, this file does not have general read permission.
Both _._k_e_y and _._p_r_i_v_a_t_e files are generated for symmetric encryption algorithms such as HMAC-MD5, even though the public and private key are equivalent.
To generate a 768-bit DSA key for the domain eexxaammppllee..ccoomm, the following command would be issued:
ddnnsssseecc--kkeeyyggeenn --aa DDSSAA --bb 776688 --nn ZZOONNEE eexxaammppllee..ccoomm
The command would print a string of the form:
KKeexxaammppllee..ccoomm..++000033++2266116600
In this example, ddnnsssseecc--kkeeyyggeenn creates the files _K_e_x_a_m_p_l_e_._c_o_m_._+_0_0_3_+_2_6_1_6_0_._k_e_y and _K_e_x_a_m_p_l_e_._c_o_m_._+_0_0_3_+_2_6_1_6_0_._p_r_i_v_a_t_e.
ddnnsssseecc--ssiiggnnzzoonnee(8), BIND 9 Administrator Reference Manual, RFC 2539, RFC 2845, RFC 4034.
Internet Systems Consortium