1 .\" Automatically generated by Pod::Man 2.25 (Pod::Simple 3.19)
4 .\" ========================================================================
5 .de Sp \" Vertical space (when we can't use .PP)
9 .de Vb \" Begin verbatim text
14 .de Ve \" End verbatim text
18 .\" Set up some character translations and predefined strings. \*(-- will
19 .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
20 .\" double quote, and \*(R" will give a right double quote. \*(C+ will
21 .\" give a nicer C++. Capital omega is used to do unbreakable dashes and
22 .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
23 .\" nothing in troff, for use with C<>.
25 .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
29 . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
30 . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
43 .\" Escape single quotes in literal strings from groff's Unicode transform.
47 .\" If the F register is turned on, we'll generate index entries on stderr for
48 .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
49 .\" entries marked with X<> in POD. Of course, you'll have to process the
50 .\" output yourself in some meaningful fashion.
53 . tm Index:\\$1\t\\n%\t"\\$2"
63 .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
64 .\" Fear. Run. Save yourself. No user-serviceable parts.
65 . \" fudge factors for nroff and troff
74 . ds #H ((1u-(\\\\n(.fu%2u))*.13m)
80 . \" simple accents for nroff and troff
90 . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
91 . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
92 . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
93 . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
94 . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
95 . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
97 . \" troff and (daisy-wheel) nroff accents
98 .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
99 .ds 8 \h'\*(#H'\(*b\h'-\*(#H'
100 .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
101 .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
102 .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
103 .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
104 .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
105 .ds ae a\h'-(\w'a'u*4/10)'e
106 .ds Ae A\h'-(\w'A'u*4/10)'E
107 . \" corrections for vroff
108 .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
109 .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
110 . \" for low resolution devices (crt and lpr)
111 .if \n(.H>23 .if \n(.V>19 \
124 .\" ========================================================================
126 .IX Title "BIO_f_cipher 3"
127 .TH BIO_f_cipher 3 "2012-01-04" "1.0.0f" "OpenSSL"
128 .\" For nroff, turn off justification. Always turn off hyphenation; it makes
129 .\" way too many mistakes in technical documents.
133 BIO_f_cipher, BIO_set_cipher, BIO_get_cipher_status, BIO_get_cipher_ctx \- cipher BIO filter
135 .IX Header "SYNOPSIS"
137 \& #include <openssl/bio.h>
138 \& #include <openssl/evp.h>
140 \& BIO_METHOD * BIO_f_cipher(void);
141 \& void BIO_set_cipher(BIO *b,const EVP_CIPHER *cipher,
142 \& unsigned char *key, unsigned char *iv, int enc);
143 \& int BIO_get_cipher_status(BIO *b)
144 \& int BIO_get_cipher_ctx(BIO *b, EVP_CIPHER_CTX **pctx)
147 .IX Header "DESCRIPTION"
148 \&\fIBIO_f_cipher()\fR returns the cipher \s-1BIO\s0 method. This is a filter
149 \&\s-1BIO\s0 that encrypts any data written through it, and decrypts any data
150 read from it. It is a \s-1BIO\s0 wrapper for the cipher routines
151 \&\fIEVP_CipherInit()\fR, \fIEVP_CipherUpdate()\fR and \fIEVP_CipherFinal()\fR.
153 Cipher BIOs do not support \fIBIO_gets()\fR or \fIBIO_puts()\fR.
155 \&\fIBIO_flush()\fR on an encryption \s-1BIO\s0 that is being written through is
156 used to signal that no more data is to be encrypted: this is used
157 to flush and possibly pad the final block through the \s-1BIO\s0.
159 \&\fIBIO_set_cipher()\fR sets the cipher of \s-1BIO\s0 \fBb\fR to \fBcipher\fR using key \fBkey\fR
160 and \s-1IV\s0 \fBiv\fR. \fBenc\fR should be set to 1 for encryption and zero for
163 When reading from an encryption \s-1BIO\s0 the final block is automatically
164 decrypted and checked when \s-1EOF\s0 is detected. \fIBIO_get_cipher_status()\fR
165 is a \fIBIO_ctrl()\fR macro which can be called to determine whether the
166 decryption operation was successful.
168 \&\fIBIO_get_cipher_ctx()\fR is a \fIBIO_ctrl()\fR macro which retrieves the internal
169 \&\s-1BIO\s0 cipher context. The retrieved context can be used in conjunction
170 with the standard cipher routines to set it up. This is useful when
171 \&\fIBIO_set_cipher()\fR is not flexible enough for the applications needs.
174 When encrypting \fIBIO_flush()\fR \fBmust\fR be called to flush the final block
175 through the \s-1BIO\s0. If it is not then the final block will fail a subsequent
178 When decrypting an error on the final block is signalled by a zero
179 return value from the read operation. A successful decrypt followed
180 by \s-1EOF\s0 will also return zero for the final read. \fIBIO_get_cipher_status()\fR
181 should be called to determine if the decrypt was successful.
183 As always, if \fIBIO_gets()\fR or \fIBIO_puts()\fR support is needed then it can
184 be achieved by preceding the cipher \s-1BIO\s0 with a buffering \s-1BIO\s0.
186 .IX Header "RETURN VALUES"
187 \&\fIBIO_f_cipher()\fR returns the cipher \s-1BIO\s0 method.
189 \&\fIBIO_set_cipher()\fR does not return a value.
191 \&\fIBIO_get_cipher_status()\fR returns 1 for a successful decrypt and 0
194 \&\fIBIO_get_cipher_ctx()\fR currently always returns 1.
196 .IX Header "EXAMPLES"
199 .IX Header "SEE ALSO"