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. 110 With this option a public key is read instead. 111 If the input contains no public key but a private key, its public part is used. 112 113 =item B<-pubout> 114 115 By default a private key is output. With this option a public 116 key will be output instead. This option is automatically set if the input is 117 a public key. 118 119 =item B<-conv_form> I<arg> 120 121 This specifies how the points on the elliptic curve are converted 122 into octet strings. Possible values are: B<compressed>, B<uncompressed> (the 123 default value) and B<hybrid>. For more information regarding 124 the point conversion forms please read the X9.62 standard. 125 B<Note> Due to patent issues the B<compressed> option is disabled 126 by default for binary curves and can be enabled by defining 127 the preprocessor macro B<OPENSSL_EC_BIN_PT_COMP> at compile time. 128 129 =item B<-param_enc> I<arg> 130 131 This specifies how the elliptic curve parameters are encoded. 132 Possible value are: B<named_curve>, i.e. the ec parameters are 133 specified by an OID, or B<explicit> where the ec parameters are 134 explicitly given (see RFC 3279 for the definition of the 135 EC parameters structures). The default value is B<named_curve>. 136 B<Note> the B<implicitlyCA> alternative, as specified in RFC 3279, 137 is currently not implemented in OpenSSL. 138 139 =item B<-no_public> 140 141 This option omits the public key components from the private key output. 142 143 =item B<-check> 144 145 This option checks the consistency of an EC private or public key. 146 147 {- $OpenSSL::safe::opt_engine_item -} 148 149 {- $OpenSSL::safe::opt_provider_item -} 150 151 =back 152 153 The L<openssl-pkey(1)> command is capable of performing all the operations 154 this command can, as well as supporting other public key types. 155 156 =head1 EXAMPLES 157 158 The documentation for the L<openssl-pkey(1)> command contains examples 159 equivalent to the ones listed here. 160 161 To encrypt a private key using triple DES: 162 163 openssl ec -in key.pem -des3 -out keyout.pem 164 165 To convert a private key from PEM to DER format: 166 167 openssl ec -in key.pem -outform DER -out keyout.der 168 169 To print out the components of a private key to standard output: 170 171 openssl ec -in key.pem -text -noout 172 173 To just output the public part of a private key: 174 175 openssl ec -in key.pem -pubout -out pubkey.pem 176 177 To change the parameters encoding to B<explicit>: 178 179 openssl ec -in key.pem -param_enc explicit -out keyout.pem 180 181 To change the point conversion form to B<compressed>: 182 183 openssl ec -in key.pem -conv_form compressed -out keyout.pem 184 185 =head1 SEE ALSO 186 187 L<openssl(1)>, 188 L<openssl-pkey(1)>, 189 L<openssl-ecparam(1)>, 190 L<openssl-dsa(1)>, 191 L<openssl-rsa(1)> 192 193 =head1 HISTORY 194 195 The B<-engine> option was deprecated in OpenSSL 3.0. 196 197 The B<-conv_form> and B<-no_public> options are no longer supported 198 with keys loaded from an engine in OpenSSL 3.0. 199 200 =head1 COPYRIGHT 201 202 Copyright 2003-2023 The OpenSSL Project Authors. All Rights Reserved. 203 204 Licensed under the Apache License 2.0 (the "License"). You may not use 205 this file except in compliance with the License. You can obtain a copy 206 in the file LICENSE in the source distribution or at 207 L<https://www.openssl.org/source/license.html>. 208 209 =cut 210
Indexes created Sat Feb 28 05:31:39 UTC 2026