1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
=pod
=head1 NAME
pkeyutl - public key algorithm utility
=head1 SYNOPSIS
B<openssl> B<pkeyutl>
[B<-in file>]
[B<-out file>]
[B<-sigfile file>]
[B<-inkey file>]
[B<-keyform PEM|DER>]
[B<-passin arg>]
[B<-peerkey file>]
[B<-peerform PEM|DER>]
[B<-pubin>]
[B<-certin>]
[B<-rev>]
[B<-sign>]
[B<-verify>]
[B<-verifyrecover>]
[B<-encrypt>]
[B<-decrypt>]
[B<-derive>]
[B<-pkeyopt opt:value>]
[B<-hexdump>]
[B<-asn1parse>]
[B<-engine id>]
=head1 DESCRIPTION
The B<pkeyutl> command can be used to perform public key operations using
any supported algorithm.
=head1 COMMAND OPTIONS
=over 4
=item B<-in filename>
This specifies the input filename to read data from or standard input
if this option is not specified.
=item B<-out filename>
specifies the output filename to write to or standard output by
default.
=item B<-inkey file>
the input key file, by default it should be a private key.
=item B<-keyform PEM|DER>
the key format PEM, DER or ENGINE.
=item B<-passin arg>
the input key password source. For more information about the format of B<arg>
see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
=item B<-peerkey file>
the peer key file, used by key derivation (agreement) operations.
=item B<-peerform PEM|DER>
the peer key format PEM, DER or ENGINE.
=item B<-engine id>
specifying an engine (by its unique B<id> string) will cause B<pkeyutl>
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.
=item B<-pubin>
the input file is a public key.
=item B<-certin>
the input is a certificate containing a public key.
=item B<-rev>
reverse the order of the input buffer. This is useful for some libraries
(such as CryptoAPI) which represent the buffer in little endian format.
=item B<-sign>
sign the input data and output the signed result. This requires
a private key.
=item B<-verify>
verify the input data against the signature file and indicate if the
verification succeeded or failed.
=item B<-verifyrecover>
verify the input data and output the recovered data.
=item B<-encrypt>
encrypt the input data using a public key.
=item B<-decrypt>
decrypt the input data using a private key.
=item B<-derive>
derive a shared secret using the peer key.
=item B<-hexdump>
hex dump the output data.
=item B<-asn1parse>
asn1parse the output data, this is useful when combined with the
B<-verifyrecover> option when an ASN1 structure is signed.
=back
=head1 NOTES
The operations and options supported vary according to the key algorithm
and its implementation. The OpenSSL operations and options are indicated below.
Unless otherwise mentioned all algorithms support the B<digest:alg> option
which specifies the digest in use for sign, verify and verifyrecover operations.
The value B<alg> should represent a digest name as used in the
EVP_get_digestbyname() function for example B<sha1>.
=head1 RSA ALGORITHM
The RSA algorithm supports encrypt, decrypt, sign, verify and verifyrecover
operations in general. Some padding modes only support some of these
operations however.
=over 4
=item -B<rsa_padding_mode:mode>
This sets the RSA padding mode. Acceptable values for B<mode> are B<pkcs1> for
PKCS#1 padding, B<sslv23> for SSLv23 padding, B<none> for no padding, B<oaep>
for B<OAEP> mode, B<x931> for X9.31 mode and B<pss> for PSS.
In PKCS#1 padding if the message digest is not set then the supplied data is
signed or verified directly instead of using a B<DigestInfo> structure. If a
digest is set then the a B<DigestInfo> structure is used and its the length
must correspond to the digest type.
For B<oeap> mode only encryption and decryption is supported.
For B<x931> if the digest type is set it is used to format the block data
otherwise the first byte is used to specify the X9.31 digest ID. Sign,
verify and verifyrecover are can be performed in this mode.
For B<pss> mode only sign and verify are supported and the digest type must be
specified.
=item B<rsa_pss_saltlen:len>
For B<pss> mode only this option specifies the salt length. Two special values
are supported: -1 sets the salt length to the digest length. When signing -2
sets the salt length to the maximum permissible value. When verifying -2 causes
the salt length to be automatically determined based on the B<PSS> block
structure.
=back
=head1 DSA ALGORITHM
The DSA algorithm supports signing and verification operations only. Currently
there are no additional options other than B<digest>. Only the SHA1
digest can be used and this digest is assumed by default.
=head1 DH ALGORITHM
The DH algorithm only supports the derivation operation and no additional
options.
=head1 EC ALGORITHM
The EC algorithm supports sign, verify and derive operations. The sign and
verify operations use ECDSA and derive uses ECDH. Currently there are no
additional options other than B<digest>. Only the SHA1 digest can be used and
this digest is assumed by default.
=head1 EXAMPLES
Sign some data using a private key:
openssl pkeyutl -sign -in file -inkey key.pem -out sig
Recover the signed data (e.g. if an RSA key is used):
openssl pkeyutl -verifyrecover -in sig -inkey key.pem
Verify the signature (e.g. a DSA key):
openssl pkeyutl -verify -in file -sigfile sig -inkey key.pem
Sign data using a message digest value (this is currently only valid for RSA):
openssl pkeyutl -sign -in file -inkey key.pem -out sig -pkeyopt digest:sha256
Derive a shared secret value:
openssl pkeyutl -derive -inkey key.pem -peerkey pubkey.pem -out secret
=head1 SEE ALSO
L<genpkey(1)|genpkey(1)>, L<pkey(1)|pkey(1)>, L<rsautl(1)|rsautl(1)>
L<dgst(1)|dgst(1)>, L<rsa(1)|rsa(1)>, L<genrsa(1)|genrsa(1)>
|
