1 .\" Automatically generated by Pod::Man 2.16 (Pod::Simple 3.05)
4 .\" ========================================================================
5 .de Sh \" Subsection heading
13 .de Sp \" Vertical space (when we can't use .PP)
17 .de Vb \" Begin verbatim text
22 .de Ve \" End verbatim text
26 .\" Set up some character translations and predefined strings. \*(-- will
27 .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
28 .\" double quote, and \*(R" will give a right double quote. \*(C+ will
29 .\" give a nicer C++. Capital omega is used to do unbreakable dashes and
30 .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
31 .\" nothing in troff, for use with C<>.
33 .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
37 . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
38 . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
51 .\" Escape single quotes in literal strings from groff's Unicode transform.
55 .\" If the F register is turned on, we'll generate index entries on stderr for
56 .\" titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and index
57 .\" entries marked with X<> in POD. Of course, you'll have to process the
58 .\" output yourself in some meaningful fashion.
61 . tm Index:\\$1\t\\n%\t"\\$2"
71 .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
72 .\" Fear. Run. Save yourself. No user-serviceable parts.
73 . \" fudge factors for nroff and troff
82 . ds #H ((1u-(\\\\n(.fu%2u))*.13m)
88 . \" simple accents for nroff and troff
98 . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
99 . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
100 . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
101 . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
102 . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
103 . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
105 . \" troff and (daisy-wheel) nroff accents
106 .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
107 .ds 8 \h'\*(#H'\(*b\h'-\*(#H'
108 .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
109 .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
110 .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
111 .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
112 .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
113 .ds ae a\h'-(\w'a'u*4/10)'e
114 .ds Ae A\h'-(\w'A'u*4/10)'E
115 . \" corrections for vroff
116 .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
117 .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
118 . \" for low resolution devices (crt and lpr)
119 .if \n(.H>23 .if \n(.V>19 \
132 .\" ========================================================================
134 .IX Title "BIO_f_cipher 3"
135 .TH BIO_f_cipher 3 "2010-02-27" "0.9.8m" "OpenSSL"
136 .\" For nroff, turn off justification. Always turn off hyphenation; it makes
137 .\" way too many mistakes in technical documents.
141 BIO_f_cipher, BIO_set_cipher, BIO_get_cipher_status, BIO_get_cipher_ctx \- cipher BIO filter
143 .IX Header "SYNOPSIS"
145 \& #include <openssl/bio.h>
146 \& #include <openssl/evp.h>
148 \& BIO_METHOD * BIO_f_cipher(void);
149 \& void BIO_set_cipher(BIO *b,const EVP_CIPHER *cipher,
150 \& unsigned char *key, unsigned char *iv, int enc);
151 \& int BIO_get_cipher_status(BIO *b)
152 \& int BIO_get_cipher_ctx(BIO *b, EVP_CIPHER_CTX **pctx)
155 .IX Header "DESCRIPTION"
156 \&\fIBIO_f_cipher()\fR returns the cipher \s-1BIO\s0 method. This is a filter
157 \&\s-1BIO\s0 that encrypts any data written through it, and decrypts any data
158 read from it. It is a \s-1BIO\s0 wrapper for the cipher routines
159 \&\fIEVP_CipherInit()\fR, \fIEVP_CipherUpdate()\fR and \fIEVP_CipherFinal()\fR.
161 Cipher BIOs do not support \fIBIO_gets()\fR or \fIBIO_puts()\fR.
163 \&\fIBIO_flush()\fR on an encryption \s-1BIO\s0 that is being written through is
164 used to signal that no more data is to be encrypted: this is used
165 to flush and possibly pad the final block through the \s-1BIO\s0.
167 \&\fIBIO_set_cipher()\fR sets the cipher of \s-1BIO\s0 \fBb\fR to \fBcipher\fR using key \fBkey\fR
168 and \s-1IV\s0 \fBiv\fR. \fBenc\fR should be set to 1 for encryption and zero for
171 When reading from an encryption \s-1BIO\s0 the final block is automatically
172 decrypted and checked when \s-1EOF\s0 is detected. \fIBIO_get_cipher_status()\fR
173 is a \fIBIO_ctrl()\fR macro which can be called to determine whether the
174 decryption operation was successful.
176 \&\fIBIO_get_cipher_ctx()\fR is a \fIBIO_ctrl()\fR macro which retrieves the internal
177 \&\s-1BIO\s0 cipher context. The retrieved context can be used in conjunction
178 with the standard cipher routines to set it up. This is useful when
179 \&\fIBIO_set_cipher()\fR is not flexible enough for the applications needs.
182 When encrypting \fIBIO_flush()\fR \fBmust\fR be called to flush the final block
183 through the \s-1BIO\s0. If it is not then the final block will fail a subsequent
186 When decrypting an error on the final block is signalled by a zero
187 return value from the read operation. A successful decrypt followed
188 by \s-1EOF\s0 will also return zero for the final read. \fIBIO_get_cipher_status()\fR
189 should be called to determine if the decrypt was successful.
191 As always, if \fIBIO_gets()\fR or \fIBIO_puts()\fR support is needed then it can
192 be achieved by preceding the cipher \s-1BIO\s0 with a buffering \s-1BIO\s0.
194 .IX Header "RETURN VALUES"
195 \&\fIBIO_f_cipher()\fR returns the cipher \s-1BIO\s0 method.
197 \&\fIBIO_set_cipher()\fR does not return a value.
199 \&\fIBIO_get_cipher_status()\fR returns 1 for a successful decrypt and 0
202 \&\fIBIO_get_cipher_ctx()\fR currently always returns 1.
204 .IX Header "EXAMPLES"
207 .IX Header "SEE ALSO"