1 =pod 2 3 =begin comment 4 {- join("\n", @autowarntext) -} 5 6 =end comment 7 8 =head1 NAME 9 10 openssl-ec - EC key processing 11 12 =head1 SYNOPSIS 13 14 B<openssl> B<ec> 15 [B<-help>] 16 [B<-inform> B<DER>|B<PEM>|B<P12>|B<ENGINE>] 17 [B<-outform> B<DER>|B<PEM>] 18 [B<-in> I<filename>|I<uri>] 19 [B<-passin> I<arg>] 20 [B<-out> I<filename>] 21 [B<-passout> I<arg>] 22 [B<-des>] 23 [B<-des3>] 24 [B<-idea>] 25 [B<-text>] 26 [B<-noout>] 27 [B<-param_out>] 28 [B<-pubin>] 29 [B<-pubout>] 30 [B<-conv_form> I<arg>] 31 [B<-param_enc> I<arg>] 32 [B<-no_public>] 33 [B<-check>] 34 {- $OpenSSL::safe::opt_engine_synopsis -}{- $OpenSSL::safe::opt_provider_synopsis -} 35 36 =head1 DESCRIPTION 37 38 The L<openssl-ec(1)> command processes EC keys. They can be converted between 39 various forms and their components printed out. B<Note> OpenSSL uses the 40 private key format specified in 'SEC 1: Elliptic Curve Cryptography' 41 (http://www.secg.org/). To convert an OpenSSL EC private key into the 42 PKCS#8 private key format use the L<openssl-pkcs8(1)> command. 43 44 =head1 OPTIONS 45 46 =over 4 47 48 =item B<-help> 49 50 Print out a usage message. 51 52 =item B<-inform> B<DER>|B<PEM>|B<P12>|B<ENGINE> 53 54 The key input format; unspecified by default. 55 See L<openssl-format-options(1)> for details. 56 57 =item B<-outform> B<DER>|B<PEM> 58 59 The key output format; the default is B<PEM>. 60 See L<openssl-format-options(1)> for details. 61 62 Private keys are an SEC1 private key or PKCS#8 format. 63 Public keys are a B<SubjectPublicKeyInfo> as specified in IETF RFC 3280. 64 65 =item B<-in> I<filename>|I<uri> 66 67 This specifies the input to read a key from or standard input if this 68 option is not specified. If the key is encrypted a pass phrase will be 69 prompted for. 70 71 =item B<-out> I<filename> 72 73 This specifies the output filename to write a key to or standard output by 74 is not specified. If any encryption options are set then a pass phrase will be 75 prompted for. The output filename should B<not> be the same as the input 76 filename. 77 78 =item B<-passin> I<arg>, B<-passout> I<arg> 79 80 The password source for the input and output file. 81 For more information about the format of B<arg> 82 see L<openssl-passphrase-options(1)>. 83 84 =item B<-des>|B<-des3>|B<-idea> 85 86 These options encrypt the private key with the DES, triple DES, IDEA or 87 any other cipher supported by OpenSSL before outputting it. A pass phrase is 88 prompted for. 89 If none of these options is specified the key is written in plain text. This 90 means that using this command to read in an encrypted key with no 91 encryption option can be used to remove the pass phrase from a key, or by 92 setting the encryption options it can be use to add or change the pass phrase. 93 These options can only be used with PEM format output files. 94 95 =item B<-text> 96 97 Prints out the public, private key components and parameters. 98 99 =item B<-noout> 100 101 This option prevents output of the encoded version of the key. 102 103 =item B<-param_out> 104 105 Print the elliptic curve parameters. 106 107 =item B<-pubin> 108 109 By default, a private key is read from the input file. With this option a 110 public key is read instead. 111 112 =item B<-pubout> 113 114 By default a private key is output. With this option a public 115 key will be output instead. This option is automatically set if the input is 116 a public key. 117 118 =item B<-conv_form> I<arg> 119 120 This specifies how the points on the elliptic curve are converted 121 into octet strings. Possible values are: B<compressed>, B<uncompressed> (the 122 default value) and B<hybrid>. For more information regarding 123 the point conversion forms please read the X9.62 standard. 124 B<Note> Due to patent issues the B<compressed> option is disabled 125 by default for binary curves and can be enabled by defining 126 the preprocessor macro B<OPENSSL_EC_BIN_PT_COMP> at compile time. 127 128 =item B<-param_enc> I<arg> 129 130 This specifies how the elliptic curve parameters are encoded. 131 Possible value are: B<named_curve>, i.e. the ec parameters are 132 specified by an OID, or B<explicit> where the ec parameters are 133 explicitly given (see RFC 3279 for the definition of the 134 EC parameters structures). The default value is B<named_curve>. 135 B<Note> the B<implicitlyCA> alternative, as specified in RFC 3279, 136 is currently not implemented in OpenSSL. 137 138 =item B<-no_public> 139 140 This option omits the public key components from the private key output. 141 142 =item B<-check> 143 144 This option checks the consistency of an EC private or public key. 145 146 {- $OpenSSL::safe::opt_engine_item -} 147 148 {- $OpenSSL::safe::opt_provider_item -} 149 150 =back 151 152 The L<openssl-pkey(1)> command is capable of performing all the operations 153 this command can, as well as supporting other public key types. 154 155 =head1 EXAMPLES 156 157 The documentation for the L<openssl-pkey(1)> command contains examples 158 equivalent to the ones listed here. 159 160 To encrypt a private key using triple DES: 161 162 openssl ec -in key.pem -des3 -out keyout.pem 163 164 To convert a private key from PEM to DER format: 165 166 openssl ec -in key.pem -outform DER -out keyout.der 167 168 To print out the components of a private key to standard output: 169 170 openssl ec -in key.pem -text -noout 171 172 To just output the public part of a private key: 173 174 openssl ec -in key.pem -pubout -out pubkey.pem 175 176 To change the parameters encoding to B<explicit>: 177 178 openssl ec -in key.pem -param_enc explicit -out keyout.pem 179 180 To change the point conversion form to B<compressed>: 181 182 openssl ec -in key.pem -conv_form compressed -out keyout.pem 183 184 =head1 SEE ALSO 185 186 L<openssl(1)>, 187 L<openssl-pkey(1)>, 188 L<openssl-ecparam(1)>, 189 L<openssl-dsa(1)>, 190 L<openssl-rsa(1)> 191 192 =head1 HISTORY 193 194 The B<-engine> option was deprecated in OpenSSL 3.0. 195 196 The B<-conv_form> and B<-no_public> options are no longer supported 197 with keys loaded from an engine in OpenSSL 3.0. 198 199 =head1 COPYRIGHT 200 201 Copyright 2003-2022 The OpenSSL Project Authors. All Rights Reserved. 202 203 Licensed under the Apache License 2.0 (the "License"). You may not use 204 this file except in compliance with the License. You can obtain a copy 205 in the file LICENSE in the source distribution or at 206 L<https://www.openssl.org/source/license.html>. 207 208 =cut 209
Indexes created Sat Apr 25 00:22:52 UTC 2026