REQ(1) OpenSSL REQ(1) NNAAMMEE openssl-req, req - PKCS#10 certificate request and certificate generat- ing utility. SSYYNNOOPPSSIISS ooppeennssssll rreeqq [--iinnffoorrmm PPEEMM||DDEERR] [--oouuttffoorrmm PPEEMM||DDEERR] [--iinn ffiilleennaammee] [--ppaassssiinn aarrgg] [--oouutt ffiilleennaammee] [--ppaassssoouutt aarrgg] [--tteexxtt] [--ppuubbkkeeyy] [--nnoooouutt] [--vveerriiffyy] [--mmoodduulluuss] [--nneeww] [--rraanndd ffiillee((ss))] [--nneewwkkeeyy rrssaa::bbiittss] [--nneewwkkeeyy aallgg::ffiillee] [--nnooddeess] [--kkeeyy ffiilleennaammee] [--kkeeyyffoorrmm PPEEMM||DDEERR] [--kkeeyyoouutt ffiillee-- nnaammee] [--kkeeyyggeenn__eennggiinnee iidd] [--[[ddiiggeesstt]]] [--ccoonnffiigg ffiilleennaammee] [--mmuullttii-- vvaalluuee--rrddnn] [--xx550099] [--ddaayyss nn] [--sseett__sseerriiaall nn] [--aassnn11--kklluuddggee] [--nnoo--aassnn11--kklluuddggee] [--nneewwhhddrr] [--eexxtteennssiioonnss sseeccttiioonn] [--rreeqqeexxttss sseeccttiioonn] [--uuttff88] [--nnaammeeoopptt] [--rreeqqoopptt] [--ssuubbjjeecctt] [--ssuubbjj aarrgg] [--bbaattcchh] [--vveerrbboossee] [--eennggiinnee iidd] DDEESSCCRRIIPPTTIIOONN The rreeqq command primarily creates and processes certificate requests in PKCS#10 format. It can additionally create self signed certificates for use as root CAs for example. CCOOMMMMAANNDD OOPPTTIIOONNSS --iinnffoorrmm DDEERR||PPEEMM This specifies the input format. The DDEERR option uses an ASN1 DER encoded form compatible with the PKCS#10. The PPEEMM form is the default format: it consists of the DDEERR format base64 encoded with additional header and footer lines. --oouuttffoorrmm DDEERR||PPEEMM This specifies the output format, the options have the same meaning as the --iinnffoorrmm option. --iinn ffiilleennaammee This specifies the input filename to read a request from or stan- dard input if this option is not specified. A request is only read if the creation options (--nneeww and --nneewwkkeeyy) are not specified. --ppaassssiinn aarrgg the input file password source. For more information about the for- mat of aarrgg see the PPAASSSS PPHHRRAASSEE AARRGGUUMMEENNTTSS section in _o_p_e_n_s_s_l(1). --oouutt ffiilleennaammee This specifies the output filename to write to or standard output by default. --ppaassssoouutt aarrgg the output file password source. For more information about the format of aarrgg see the PPAASSSS PPHHRRAASSEE AARRGGUUMMEENNTTSS section in _o_p_e_n_s_s_l(1). --tteexxtt prints out the certificate request in text form. --ssuubbjjeecctt prints out the request subject (or certificate subject if --xx550099 is specified) --ppuubbkkeeyy outputs the public key. --nnoooouutt this option prevents output of the encoded version of the request. --mmoodduulluuss this option prints out the value of the modulus of the public key contained in the request. --vveerriiffyy verifies the signature on the request. --nneeww this option generates a new certificate request. It will prompt the user for the relevant field values. The actual fields prompted for and their maximum and minimum sizes are specified in the configura- tion file and any requested extensions. If the --kkeeyy option is not used it will generate a new RSA private key using information specified in the configuration file. --ssuubbjj aarrgg Replaces subject field of input request with specified data and outputs modified request. The arg must be formatted as _/_t_y_p_e_0_=_v_a_l_u_e_0_/_t_y_p_e_1_=_v_a_l_u_e_1_/_t_y_p_e_2_=_._._., characters may be escaped by \ (backslash), no spaces are skipped. --rraanndd ffiillee((ss)) a file or files containing random data used to seed the random num- ber generator, or an EGD socket (see _R_A_N_D___e_g_d(3)). Multiple files can be specified separated by a OS-dependent character. The sepa- rator is ;; for MS-Windows, ,, for OpenVMS, and :: for all others. --nneewwkkeeyy aarrgg this option creates a new certificate request and a new private key. The argument takes one of several forms. rrssaa::nnbbiittss, where nnbbiittss is the number of bits, generates an RSA key nnbbiittss in size. If nnbbiittss is omitted, i.e. --nneewwkkeeyy rrssaa specified, the default key size, specified in the configuration file is used. All other algorithms support the --nneewwkkeeyy aallgg::ffiillee form, where file may be an algorithm parameter file, created by the ggeennppkkeeyy --ggeenn-- ppaarraamm command or and X.509 certificate for a key with approriate algorithm. ppaarraamm::ffiillee generates a key using the parameter file or certificate ffiillee, the algorithm is determined by the parameters. aallggnnaammee::ffiillee use algorithm aallggnnaammee and parameter file ffiillee: the two algorithms must match or an error occurs. aallggnnaammee just uses algorithm aallggnnaammee, and parameters, if neccessary should be specified via --ppkkeeyyoopptt parameter. ddssaa::ffiilleennaammee generates a DSA key using the parameters in the file ffiilleennaammee. eecc::ffiilleennaammee generates EC key (usable both with ECDSA or ECDH algorithms), ggoosstt22000011::ffiilleennaammee generates GOST R 34.10-2001 key (requires ccccggoosstt engine configured in the configuration file). If just ggoosstt22000011 is specified a parameter set should be specified by --ppkkeeyyoopptt ppaarraammsseett::XX --ppkkeeyyoopptt oopptt::vvaalluuee set the public key algorithm option oopptt to vvaalluuee. The precise set of options supported depends on the public key algorithm used and its implementation. See KKEEYY GGEENNEERRAATTIIOONN OOPPTTIIOONNSS in the ggeennppkkeeyy man- ual page for more details. --kkeeyy ffiilleennaammee This specifies the file to read the private key from. It also accepts PKCS#8 format private keys for PEM format files. --kkeeyyffoorrmm PPEEMM||DDEERR the format of the private key file specified in the --kkeeyy argument. PEM is the default. --kkeeyyoouutt ffiilleennaammee this gives the filename to write the newly created private key to. If this option is not specified then the filename present in the configuration file is used. --nnooddeess if this option is specified then if a private key is created it will not be encrypted. --[[ddiiggeesstt]] this specifies the message digest to sign the request with (such as --mmdd55, --sshhaa11). This overrides the digest algorithm specified in the configuration file. Some public key algorithms may override this choice. For instance, DSA signatures always use SHA1, GOST R 34.10 signatures always use GOST R 34.11-94 (--mmdd__ggoosstt9944). --ccoonnffiigg ffiilleennaammee this allows an alternative configuration file to be specified, this overrides the compile time filename or any specified in the OOPPEENNSSSSLL__CCOONNFF environment variable. --ssuubbjj aarrgg sets subject name for new request or supersedes the subject name when processing a request. The arg must be formatted as _/_t_y_p_e_0_=_v_a_l_u_e_0_/_t_y_p_e_1_=_v_a_l_u_e_1_/_t_y_p_e_2_=_._._., characters may be escaped by \ (backslash), no spaces are skipped. --mmuullttiivvaalluuee--rrddnn this option causes the -subj argument to be interpreted with full support for multivalued RDNs. Example: _/_D_C_=_o_r_g_/_D_C_=_O_p_e_n_S_S_L_/_D_C_=_u_s_e_r_s_/_U_I_D_=_1_2_3_4_5_6_+_C_N_=_J_o_h_n _D_o_e If -multi-rdn is not used then the UID value is _1_2_3_4_5_6_+_C_N_=_J_o_h_n _D_o_e. --xx550099 this option outputs a self signed certificate instead of a certifi- cate request. This is typically used to generate a test certificate or a self signed root CA. The extensions added to the certificate (if any) are specified in the configuration file. Unless specified using the sseett__sseerriiaall option, a large random number will be used for the serial number. If existing request is specified with the --iinn option, it is con- verted to the self signed certificate otherwise new request is cre- ated. --ddaayyss nn when the --xx550099 option is being used this specifies the number of days to certify the certificate for. The default is 30 days. --sseett__sseerriiaall nn serial number to use when outputting a self signed certificate. This may be specified as a decimal value or a hex value if preceded by 00xx. It is possible to use negative serial numbers but this is not recommended. --eexxtteennssiioonnss sseeccttiioonn --rreeqqeexxttss sseeccttiioonn these options specify alternative sections to include certificate extensions (if the --xx550099 option is present) or certificate request extensions. This allows several different sections to be used in the same configuration file to specify requests for a variety of purposes. --uuttff88 this option causes field values to be interpreted as UTF8 strings, by default they are interpreted as ASCII. This means that the field values, whether prompted from a terminal or obtained from a config- uration file, must be valid UTF8 strings. --nnaammeeoopptt ooppttiioonn option which determines how the subject or issuer names are dis- played. The ooppttiioonn argument can be a single option or multiple options separated by commas. Alternatively the --nnaammeeoopptt switch may be used more than once to set multiple options. See the _x_5_0_9(1) manual page for details. --rreeqqoopptt customise the output format used with --tteexxtt. The ooppttiioonn argument can be a single option or multiple options separated by commas. See discission of the --cceerrttoopptt parameter in the xx550099 command. --aassnn11--kklluuddggee by default the rreeqq command outputs certificate requests containing no attributes in the correct PKCS#10 format. However certain CAs will only accept requests containing no attributes in an invalid form: this option produces this invalid format. More precisely the AAttttrriibbuutteess in a PKCS#10 certificate request are defined as a SSEETT OOFF AAttttrriibbuuttee. They are nnoott OOPPTTIIOONNAALL so if no attributes are present then they should be encoded as an empty SSEETT OOFF. The invalid form does not include the empty SSEETT OOFF whereas the correct form does. It should be noted that very few CAs still require the use of this option. --nnoo--aassnn11--kklluuddggee Reverses effect of --aassnn11--kklluuddggee --nneewwhhddrr Adds the word NNEEWW to the PEM file header and footer lines on the outputted request. Some software (Netscape certificate server) and some CAs need this. --bbaattcchh non-interactive mode. --vveerrbboossee print extra details about the operations being performed. --eennggiinnee iidd specifying an engine (by its unique iidd string) will cause rreeqq to attempt to obtain a functional reference to the specified engine, thus initialising it if needed. The engine will then be set as the default for all available algorithms. --kkeeyyggeenn__eennggiinnee iidd specifies an engine (by its unique iidd string) which would be used for key generation operations. CCOONNFFIIGGUURRAATTIIOONN FFIILLEE FFOORRMMAATT The configuration options are specified in the rreeqq section of the con- figuration file. As with all configuration files if no value is speci- fied in the specific section (i.e. rreeqq) then the initial unnamed or ddeeffaauulltt section is searched too. The options available are described in detail below. iinnppuutt__ppaasssswwoorrdd oouuttppuutt__ppaasssswwoorrdd The passwords for the input private key file (if present) and the output private key file (if one will be created). The command line options ppaassssiinn and ppaassssoouutt override the configuration file values. ddeeffaauulltt__bbiittss Specifies the default key size in bits. This option is used in conjunction with the --nneeww option to generate a new key. It can be overridden by specifying an explicit key size in the --nneewwkkeeyy option. The smallest accepted key size is 512 bits. If no key size is specified then 2048 bits is used. ddeeffaauulltt__kkeeyyffiillee This is the default filename to write a private key to. If not specified the key is written to standard output. This can be over- ridden by the --kkeeyyoouutt option. ooiidd__ffiillee This specifies a file containing additional OOBBJJEECCTT IIDDEENNTTIIFFIIEERRSS. Each line of the file should consist of the numerical form of the object identifier followed by white space then the short name fol- lowed by white space and finally the long name. ooiidd__sseeccttiioonn This specifies a section in the configuration file containing extra object identifiers. Each line should consist of the short name of the object identifier followed by == and the numerical form. The short and long names are the same when this option is used. RRAANNDDFFIILLEE This specifies a filename in which random number seed information is placed and read from, or an EGD socket (see _R_A_N_D___e_g_d(3)). It is used for private key generation. eennccrryypptt__kkeeyy If this is set to nnoo then if a private key is generated it is nnoott encrypted. This is equivalent to the --nnooddeess command line option. For compatibility eennccrryypptt__rrssaa__kkeeyy is an equivalent option. ddeeffaauulltt__mmdd This option specifies the digest algorithm to use. Possible values include mmdd55 sshhaa11 mmddcc22. This option can be overridden on the command line. ssttrriinngg__mmaasskk This option masks out the use of certain string types in certain fields. Most users will not need to change this option. It can be set to several values ddeeffaauulltt which is also the default option uses PrintableStrings, T61Strings and BMPStrings if the ppkkiixx value is used then only PrintableStrings and BMPStrings will be used. This follows the PKIX recommendation in RFC2459. If the uuttff88oonnllyy option is used then only UTF8Strings will be used: this is the PKIX recommendation in RFC2459 after 2003. Finally the nnoommbbssttrr option just uses PrintableStrings and T61Strings: certain software has problems with BMPStrings and UTF8Strings: in particular Net- scape. rreeqq__eexxtteennssiioonnss this specifies the configuration file section containing a list of extensions to add to the certificate request. It can be overridden by the --rreeqqeexxttss command line switch. See the _x_5_0_9_v_3___c_o_n_f_i_g(5) man- ual page for details of the extension section format. xx550099__eexxtteennssiioonnss this specifies the configuration file section containing a list of extensions to add to certificate generated when the --xx550099 switch is used. It can be overridden by the --eexxtteennssiioonnss command line switch. pprroommpptt if set to the value nnoo this disables prompting of certificate fields and just takes values from the config file directly. It also changes the expected format of the ddiissttiinngguuiisshheedd__nnaammee and aattttrriibbuutteess sections. uuttff88 if set to the value yyeess then field values to be interpreted as UTF8 strings, by default they are interpreted as ASCII. This means that the field values, whether prompted from a terminal or obtained from a configuration file, must be valid UTF8 strings. aattttrriibbuutteess this specifies the section containing any request attributes: its format is the same as ddiissttiinngguuiisshheedd__nnaammee. Typically these may con- tain the challengePassword or unstructuredName types. They are cur- rently ignored by OpenSSL's request signing utilities but some CAs might want them. ddiissttiinngguuiisshheedd__nnaammee This specifies the section containing the distinguished name fields to prompt for when generating a certificate or certificate request. The format is described in the next section. DDIISSTTIINNGGUUIISSHHEEDD NNAAMMEE AANNDD AATTTTRRIIBBUUTTEE SSEECCTTIIOONN FFOORRMMAATT There are two separate formats for the distinguished name and attribute sections. If the pprroommpptt option is set to nnoo then these sections just consist of field names and values: for example, CN=My Name OU=My Organization emailAddress=someone@somewhere.org This allows external programs (e.g. GUI based) to generate a template file with all the field names and values and just pass it to rreeqq. An example of this kind of configuration file is contained in the EEXXAAMMPPLLEESS section. Alternatively if the pprroommpptt option is absent or not set to nnoo then the file contains field prompting information. It consists of lines of the form: fieldName="prompt" fieldName_default="default field value" fieldName_min= 2 fieldName_max= 4 "fieldName" is the field name being used, for example commonName (or CN). The "prompt" string is used to ask the user to enter the relevant details. If the user enters nothing then the default value is used if no default value is present then the field is omitted. A field can still be omitted if a default value is present if the user just enters the '.' character. The number of characters entered must be between the fieldName_min and fieldName_max limits: there may be additional restrictions based on the field being used (for example countryName can only ever be two charac- ters long and must fit in a PrintableString). Some fields (such as organizationName) can be used more than once in a DN. This presents a problem because configuration files will not recog- nize the same name occurring twice. To avoid this problem if the field- Name contains some characters followed by a full stop they will be ignored. So for example a second organizationName can be input by call- ing it "1.organizationName". The actual permitted field names are any object identifier short or long names. These are compiled into OpenSSL and include the usual val- ues such as commonName, countryName, localityName, organizationName, organizationalUnitName, stateOrProvinceName. Additionally emailAddress is include as well as name, surname, givenName initials and dnQuali- fier. Additional object identifiers can be defined with the ooiidd__ffiillee or ooiidd__sseeccttiioonn options in the configuration file. Any additional fields will be treated as though they were a DirectoryString. EEXXAAMMPPLLEESS Examine and verify certificate request: openssl req -in req.pem -text -verify -noout Create a private key and then generate a certificate request from it: openssl genrsa -out key.pem 2048 openssl req -new -key key.pem -out req.pem The same but just using req: openssl req -newkey rsa:2048 -keyout key.pem -out req.pem Generate a self signed root certificate: openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem Example of a file pointed to by the ooiidd__ffiillee option: 1.2.3.4 shortName A longer Name 1.2.3.6 otherName Other longer Name Example of a section pointed to by ooiidd__sseeccttiioonn making use of variable expansion: testoid1=1.2.3.5 testoid2=${testoid1}.6 Sample configuration file prompting for field values: [ req ] default_bits = 2048 default_keyfile = privkey.pem distinguished_name = req_distinguished_name attributes = req_attributes x509_extensions = v3_ca dirstring_type = nobmp [ req_distinguished_name ] countryName = Country Name (2 letter code) countryName_default = AU countryName_min = 2 countryName_max = 2 localityName = Locality Name (eg, city) organizationalUnitName = Organizational Unit Name (eg, section) commonName = Common Name (eg, YOUR name) commonName_max = 64 emailAddress = Email Address emailAddress_max = 40 [ req_attributes ] challengePassword = A challenge password challengePassword_min = 4 challengePassword_max = 20 [ v3_ca ] subjectKeyIdentifier=hash authorityKeyIdentifier=keyid:always,issuer:always basicConstraints = CA:true Sample configuration containing all field values: RANDFILE = $ENV::HOME/.rnd [ req ] default_bits = 2048 default_keyfile = keyfile.pem distinguished_name = req_distinguished_name attributes = req_attributes prompt = no output_password = mypass [ req_distinguished_name ] C = GB ST = Test State or Province L = Test Locality O = Organization Name OU = Organizational Unit Name CN = Common Name emailAddress = test@email.address [ req_attributes ] challengePassword = A challenge password NNOOTTEESS The header and footer lines in the PPEEMM format are normally: -----BEGIN CERTIFICATE REQUEST----- -----END CERTIFICATE REQUEST----- some software (some versions of Netscape certificate server) instead needs: -----BEGIN NEW CERTIFICATE REQUEST----- -----END NEW CERTIFICATE REQUEST----- which is produced with the --nneewwhhddrr option but is otherwise compatible. Either form is accepted transparently on input. The certificate requests generated by XXeennrroollll with MSIE have extensions added. It includes the kkeeyyUUssaaggee extension which determines the type of key (signature only or general purpose) and any additional OIDs entered by the script in an extendedKeyUsage extension. DDIIAAGGNNOOSSTTIICCSS The following messages are frequently asked about: Using configuration from /some/path/openssl.cnf Unable to load config info This is followed some time later by... unable to find 'distinguished_name' in config problems making Certificate Request The first error message is the clue: it can't find the configuration file! Certain operations (like examining a certificate request) don't need a configuration file so its use isn't enforced. Generation of cer- tificates or requests however does need a configuration file. This could be regarded as a bug. Another puzzling message is this: Attributes: a0:00 this is displayed when no attributes are present and the request includes the correct empty SSEETT OOFF structure (the DER encoding of which is 0xa0 0x00). If you just see: Attributes: then the SSEETT OOFF is missing and the encoding is technically invalid (but it is tolerated). See the description of the command line option --aassnn11--kklluuddggee for more information. EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS The variable OOPPEENNSSSSLL__CCOONNFF if defined allows an alternative configura- tion file location to be specified, it will be overridden by the --ccoonn-- ffiigg command line switch if it is present. For compatibility reasons the SSSSLLEEAAYY__CCOONNFF environment variable serves the same purpose but its use is discouraged. BBUUGGSS OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour. This can cause problems if you need characters that aren't available in PrintableStrings and you don't want to or can't use BMPStrings. As a consequence of the T61String handling the only correct way to rep- resent accented characters in OpenSSL is to use a BMPString: unfortu- nately Netscape currently chokes on these. If you have to use accented characters with Netscape and MSIE then you currently need to use the invalid T61String form. The current prompting is not very friendly. It doesn't allow you to confirm what you've just entered. Other things like extensions in cer- tificate requests are statically defined in the configuration file. Some of these: like an email address in subjectAltName should be input by the user. SSEEEE AALLSSOO _x_5_0_9(1), _c_a(1), _g_e_n_r_s_a(1), _g_e_n_d_s_a(1), _c_o_n_f_i_g(5), _x_5_0_9_v_3___c_o_n_f_i_g(5) 1.0.2u 2019-12-20 REQ(1)