summaryrefslogtreecommitdiffstats
path: root/secure/lib/libcrypto/man/RSA_public_encrypt.3
blob: 693be67e90bebc0b91313492950085d66efcd2f1 (plain)
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
.\" Automatically generated by Pod::Man 2.28 (Pod::Simple 3.30)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" Set up some character translations and predefined strings.  \*(-- will
.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
.\" nothing in troff, for use with C<>.
.tr \(*W-
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.ie n \{\
.    ds -- \(*W-
.    ds PI pi
.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
.    ds L" ""
.    ds R" ""
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds -- \|\(em\|
.    ds PI \(*p
.    ds L" ``
.    ds R" ''
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is turned on, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{
.    if \nF \{
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\"
.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
.\" Fear.  Run.  Save yourself.  No user-serviceable parts.
.    \" fudge factors for nroff and troff
.if n \{\
.    ds #H 0
.    ds #V .8m
.    ds #F .3m
.    ds #[ \f1
.    ds #] \fP
.\}
.if t \{\
.    ds #H ((1u-(\\\\n(.fu%2u))*.13m)
.    ds #V .6m
.    ds #F 0
.    ds #[ \&
.    ds #] \&
.\}
.    \" simple accents for nroff and troff
.if n \{\
.    ds ' \&
.    ds ` \&
.    ds ^ \&
.    ds , \&
.    ds ~ ~
.    ds /
.\}
.if t \{\
.    ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
.    ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
.    ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
.    ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
.    ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
.    ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
.\}
.    \" troff and (daisy-wheel) nroff accents
.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
.ds ae a\h'-(\w'a'u*4/10)'e
.ds Ae A\h'-(\w'A'u*4/10)'E
.    \" corrections for vroff
.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
.    \" for low resolution devices (crt and lpr)
.if \n(.H>23 .if \n(.V>19 \
\{\
.    ds : e
.    ds 8 ss
.    ds o a
.    ds d- d\h'-1'\(ga
.    ds D- D\h'-1'\(hy
.    ds th \o'bp'
.    ds Th \o'LP'
.    ds ae ae
.    ds Ae AE
.\}
.rm #[ #] #H #V #F C
.\" ========================================================================
.\"
.IX Title "RSA_public_encrypt 3"
.TH RSA_public_encrypt 3 "2016-05-03" "1.0.2h" "OpenSSL"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
RSA_public_encrypt, RSA_private_decrypt \- RSA public key cryptography
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/rsa.h>
\&
\& int RSA_public_encrypt(int flen, unsigned char *from,
\&    unsigned char *to, RSA *rsa, int padding);
\&
\& int RSA_private_decrypt(int flen, unsigned char *from,
\&     unsigned char *to, RSA *rsa, int padding);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fIRSA_public_encrypt()\fR encrypts the \fBflen\fR bytes at \fBfrom\fR (usually a
session key) using the public key \fBrsa\fR and stores the ciphertext in
\&\fBto\fR. \fBto\fR must point to RSA_size(\fBrsa\fR) bytes of memory.
.PP
\&\fBpadding\fR denotes one of the following modes:
.IP "\s-1RSA_PKCS1_PADDING\s0" 4
.IX Item "RSA_PKCS1_PADDING"
\&\s-1PKCS\s0 #1 v1.5 padding. This currently is the most widely used mode.
.IP "\s-1RSA_PKCS1_OAEP_PADDING\s0" 4
.IX Item "RSA_PKCS1_OAEP_PADDING"
EME-OAEP as defined in \s-1PKCS\s0 #1 v2.0 with \s-1SHA\-1, MGF1\s0 and an empty
encoding parameter. This mode is recommended for all new applications.
.IP "\s-1RSA_SSLV23_PADDING\s0" 4
.IX Item "RSA_SSLV23_PADDING"
\&\s-1PKCS\s0 #1 v1.5 padding with an SSL-specific modification that denotes
that the server is \s-1SSL3\s0 capable.
.IP "\s-1RSA_NO_PADDING\s0" 4
.IX Item "RSA_NO_PADDING"
Raw \s-1RSA\s0 encryption. This mode should \fIonly\fR be used to implement
cryptographically sound padding modes in the application code.
Encrypting user data directly with \s-1RSA\s0 is insecure.
.PP
\&\fBflen\fR must be less than RSA_size(\fBrsa\fR) \- 11 for the \s-1PKCS\s0 #1 v1.5
based padding modes, less than RSA_size(\fBrsa\fR) \- 41 for
\&\s-1RSA_PKCS1_OAEP_PADDING\s0 and exactly RSA_size(\fBrsa\fR) for \s-1RSA_NO_PADDING.\s0
The random number generator must be seeded prior to calling
\&\fIRSA_public_encrypt()\fR.
.PP
\&\fIRSA_private_decrypt()\fR decrypts the \fBflen\fR bytes at \fBfrom\fR using the
private key \fBrsa\fR and stores the plaintext in \fBto\fR. \fBto\fR must point
to a memory section large enough to hold the decrypted data (which is
smaller than RSA_size(\fBrsa\fR)). \fBpadding\fR is the padding mode that
was used to encrypt the data.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fIRSA_public_encrypt()\fR returns the size of the encrypted data (i.e.,
RSA_size(\fBrsa\fR)). \fIRSA_private_decrypt()\fR returns the size of the
recovered plaintext.
.PP
On error, \-1 is returned; the error codes can be
obtained by \fIERR_get_error\fR\|(3).
.SH "CONFORMING TO"
.IX Header "CONFORMING TO"
\&\s-1SSL, PKCS\s0 #1 v2.0
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fIERR_get_error\fR\|(3), \fIrand\fR\|(3), \fIrsa\fR\|(3),
\&\fIRSA_size\fR\|(3)
.SH "HISTORY"
.IX Header "HISTORY"
The \fBpadding\fR argument was added in SSLeay 0.8. \s-1RSA_NO_PADDING\s0 is
available since SSLeay 0.9.0, \s-1OAEP\s0 was added in OpenSSL 0.9.2b.
OpenPOWER on IntegriCloud