3.\"
4.\" Standard preamble:
5.\" ======================================================================
6.de Sh \" Subsection heading
7.br
8.if t .Sp
9.ne 5
10.PP
11\fB\\$1\fR
12.PP
13..
14.de Sp \" Vertical space (when we can't use .PP)
15.if t .sp .5v
16.if n .sp
17..
18.de Ip \" List item
19.br
20.ie \\n(.$>=3 .ne \\$3
21.el .ne 3
22.IP "\\$1" \\$2
23..
24.de Vb \" Begin verbatim text
25.ft CW
26.nf
27.ne \\$1
28..
29.de Ve \" End verbatim text
30.ft R
31
32.fi
33..
34.\" Set up some character translations and predefined strings. \*(-- will
35.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
36.\" double quote, and \*(R" will give a right double quote. | will give a
37.\" real vertical bar. \*(C+ will give a nicer C++. Capital omega is used
38.\" to do unbreakable dashes and therefore won't be available. \*(C` and
39.\" \*(C' expand to `' in nroff, nothing in troff, for use with C<>
40.tr \(*W-|\(bv\*(Tr
41.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
42.ie n \{\
43. ds -- \(*W-
44. ds PI pi
45. if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
46. if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
47. ds L" ""
48. ds R" ""
49. ds C` ""
50. ds C' ""
51'br\}
52.el\{\
53. ds -- \|\(em\|
54. ds PI \(*p
55. ds L" ``
56. ds R" ''
57'br\}
58.\"
59.\" If the F register is turned on, we'll generate index entries on stderr
60.\" for titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and
61.\" index entries marked with X<> in POD. Of course, you'll have to process
62.\" the output yourself in some meaningful fashion.
63.if \nF \{\
64. de IX
65. tm Index:\\$1\t\\n%\t"\\$2"
66..
67. nr % 0
68. rr F
69.\}
70.\"
71.\" For nroff, turn off justification. Always turn off hyphenation; it
72.\" makes way too many mistakes in technical documents.
73.hy 0
74.if n .na
75.\"
76.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
77.\" Fear. Run. Save yourself. No user-serviceable parts.
78.bd B 3
79. \" fudge factors for nroff and troff
80.if n \{\
81. ds #H 0
82. ds #V .8m
83. ds #F .3m
84. ds #[ \f1
85. ds #] \fP
86.\}
87.if t \{\
88. ds #H ((1u-(\\\\n(.fu%2u))*.13m)
89. ds #V .6m
90. ds #F 0
91. ds #[ \&
92. ds #] \&
93.\}
94. \" simple accents for nroff and troff
95.if n \{\
96. ds ' \&
97. ds ` \&
98. ds ^ \&
99. ds , \&
100. ds ~ ~
101. ds /
102.\}
103.if t \{\
104. ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
105. ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
106. ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
107. ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
108. ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
109. ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
110.\}
111. \" troff and (daisy-wheel) nroff accents
112.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
113.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
114.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
115.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
116.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
117.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
118.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
119.ds ae a\h'-(\w'a'u*4/10)'e
120.ds Ae A\h'-(\w'A'u*4/10)'E
121. \" corrections for vroff
122.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
123.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
124. \" for low resolution devices (crt and lpr)
125.if \n(.H>23 .if \n(.V>19 \
126\{\
127. ds : e
128. ds 8 ss
129. ds o a
130. ds d- d\h'-1'\(ga
131. ds D- D\h'-1'\(hy
132. ds th \o'bp'
133. ds Th \o'LP'
134. ds ae ae
135. ds Ae AE
136.\}
137.rm #[ #] #H #V #F C
138.\" ======================================================================
139.\"
140.IX Title "BIO_f_md 3"
| 3.\"
4.\" Standard preamble:
5.\" ======================================================================
6.de Sh \" Subsection heading
7.br
8.if t .Sp
9.ne 5
10.PP
11\fB\\$1\fR
12.PP
13..
14.de Sp \" Vertical space (when we can't use .PP)
15.if t .sp .5v
16.if n .sp
17..
18.de Ip \" List item
19.br
20.ie \\n(.$>=3 .ne \\$3
21.el .ne 3
22.IP "\\$1" \\$2
23..
24.de Vb \" Begin verbatim text
25.ft CW
26.nf
27.ne \\$1
28..
29.de Ve \" End verbatim text
30.ft R
31
32.fi
33..
34.\" Set up some character translations and predefined strings. \*(-- will
35.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
36.\" double quote, and \*(R" will give a right double quote. | will give a
37.\" real vertical bar. \*(C+ will give a nicer C++. Capital omega is used
38.\" to do unbreakable dashes and therefore won't be available. \*(C` and
39.\" \*(C' expand to `' in nroff, nothing in troff, for use with C<>
40.tr \(*W-|\(bv\*(Tr
41.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
42.ie n \{\
43. ds -- \(*W-
44. ds PI pi
45. if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
46. if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
47. ds L" ""
48. ds R" ""
49. ds C` ""
50. ds C' ""
51'br\}
52.el\{\
53. ds -- \|\(em\|
54. ds PI \(*p
55. ds L" ``
56. ds R" ''
57'br\}
58.\"
59.\" If the F register is turned on, we'll generate index entries on stderr
60.\" for titles (.TH), headers (.SH), subsections (.Sh), items (.Ip), and
61.\" index entries marked with X<> in POD. Of course, you'll have to process
62.\" the output yourself in some meaningful fashion.
63.if \nF \{\
64. de IX
65. tm Index:\\$1\t\\n%\t"\\$2"
66..
67. nr % 0
68. rr F
69.\}
70.\"
71.\" For nroff, turn off justification. Always turn off hyphenation; it
72.\" makes way too many mistakes in technical documents.
73.hy 0
74.if n .na
75.\"
76.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
77.\" Fear. Run. Save yourself. No user-serviceable parts.
78.bd B 3
79. \" fudge factors for nroff and troff
80.if n \{\
81. ds #H 0
82. ds #V .8m
83. ds #F .3m
84. ds #[ \f1
85. ds #] \fP
86.\}
87.if t \{\
88. ds #H ((1u-(\\\\n(.fu%2u))*.13m)
89. ds #V .6m
90. ds #F 0
91. ds #[ \&
92. ds #] \&
93.\}
94. \" simple accents for nroff and troff
95.if n \{\
96. ds ' \&
97. ds ` \&
98. ds ^ \&
99. ds , \&
100. ds ~ ~
101. ds /
102.\}
103.if t \{\
104. ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
105. ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
106. ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
107. ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
108. ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
109. ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
110.\}
111. \" troff and (daisy-wheel) nroff accents
112.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
113.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
114.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
115.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
116.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
117.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
118.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
119.ds ae a\h'-(\w'a'u*4/10)'e
120.ds Ae A\h'-(\w'A'u*4/10)'E
121. \" corrections for vroff
122.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
123.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
124. \" for low resolution devices (crt and lpr)
125.if \n(.H>23 .if \n(.V>19 \
126\{\
127. ds : e
128. ds 8 ss
129. ds o a
130. ds d- d\h'-1'\(ga
131. ds D- D\h'-1'\(hy
132. ds th \o'bp'
133. ds Th \o'LP'
134. ds ae ae
135. ds Ae AE
136.\}
137.rm #[ #] #H #V #F C
138.\" ======================================================================
139.\"
140.IX Title "BIO_f_md 3"
|
142.UC
143.SH "NAME"
144BIO_f_md, BIO_set_md, BIO_get_md, BIO_get_md_ctx \- message digest \s-1BIO\s0 filter
145.SH "SYNOPSIS"
146.IX Header "SYNOPSIS"
147.Vb 2
148\& #include <openssl/bio.h>
149\& #include <openssl/evp.h>
150.Ve
151.Vb 4
152\& BIO_METHOD * BIO_f_md(void);
153\& int BIO_set_md(BIO *b,EVP_MD *md);
154\& int BIO_get_md(BIO *b,EVP_MD **mdp);
155\& int BIO_get_md_ctx(BIO *b,EVP_MD_CTX **mdcp);
156.Ve
157.SH "DESCRIPTION"
158.IX Header "DESCRIPTION"
159\&\fIBIO_f_md()\fR returns the message digest \s-1BIO\s0 method. This is a filter
160\&\s-1BIO\s0 that digests any data passed through it, it is a \s-1BIO\s0 wrapper
161for the digest routines \fIEVP_DigestInit()\fR, \fIEVP_DigestUpdate()\fR
162and \fIEVP_DigestFinal()\fR.
163.PP
164Any data written or read through a digest \s-1BIO\s0 using \fIBIO_read()\fR and
165\&\fIBIO_write()\fR is digested.
166.PP
167\&\fIBIO_gets()\fR, if its \fBsize\fR parameter is large enough finishes the
168digest calculation and returns the digest value. \fIBIO_puts()\fR is
169not supported.
170.PP
171\&\fIBIO_reset()\fR reinitialises a digest \s-1BIO\s0.
172.PP
173\&\fIBIO_set_md()\fR sets the message digest of \s-1BIO\s0 \fBb\fR to \fBmd\fR: this
174must be called to initialize a digest \s-1BIO\s0 before any data is
175passed through it. It is a \fIBIO_ctrl()\fR macro.
176.PP
177\&\fIBIO_get_md()\fR places the a pointer to the digest BIOs digest method
178in \fBmdp\fR, it is a \fIBIO_ctrl()\fR macro.
179.PP
180\&\fIBIO_get_md_ctx()\fR returns the digest BIOs context into \fBmdcp\fR.
181.SH "NOTES"
182.IX Header "NOTES"
183The context returned by \fIBIO_get_md_ctx()\fR can be used in calls
184to \fIEVP_DigestFinal()\fR and also the signature routines \fIEVP_SignFinal()\fR
185and \fIEVP_VerifyFinal()\fR.
186.PP
187The context returned by \fIBIO_get_md_ctx()\fR is an internal context
188structure. Changes made to this context will affect the digest
189\&\s-1BIO\s0 itself and the context pointer will become invalid when the digest
190\&\s-1BIO\s0 is freed.
191.PP
192After the digest has been retrieved from a digest \s-1BIO\s0 it must be
193reinitialized by calling \fIBIO_reset()\fR, or \fIBIO_set_md()\fR before any more
194data is passed through it.
195.PP
196If an application needs to call \fIBIO_gets()\fR or \fIBIO_puts()\fR through
197a chain containing digest BIOs then this can be done by prepending
198a buffering \s-1BIO\s0.
199.SH "RETURN VALUES"
200.IX Header "RETURN VALUES"
201\&\fIBIO_f_md()\fR returns the digest \s-1BIO\s0 method.
202.PP
203\&\fIBIO_set_md()\fR, \fIBIO_get_md()\fR and \fIBIO_md_ctx()\fR return 1 for success and
2040 for failure.
205.SH "EXAMPLES"
206.IX Header "EXAMPLES"
207The following example creates a \s-1BIO\s0 chain containing an \s-1SHA1\s0 and \s-1MD5\s0
208digest \s-1BIO\s0 and passes the string \*(L"Hello World\*(R" through it. Error
209checking has been omitted for clarity.
210.PP
211.Vb 14
212\& BIO *bio, *mdtmp;
213\& char message[] = "Hello World";
214\& bio = BIO_new(BIO_s_null());
215\& mdtmp = BIO_new(BIO_f_md());
216\& BIO_set_md(mdtmp, EVP_sha1());
217\& /* For BIO_push() we want to append the sink BIO and keep a note of
218\& * the start of the chain.
219\& */
220\& bio = BIO_push(mdtmp, bio);
221\& mdtmp = BIO_new(BIO_f_md());
222\& BIO_set_md(mdtmp, EVP_md5());
223\& bio = BIO_push(mdtmp, bio);
224\& /* Note: mdtmp can now be discarded */
225\& BIO_write(bio, message, strlen(message));
226.Ve
227The next example digests data by reading through a chain instead:
228.PP
229.Vb 14
230\& BIO *bio, *mdtmp;
231\& char buf[1024];
232\& int rdlen;
233\& bio = BIO_new_file(file, "rb");
234\& mdtmp = BIO_new(BIO_f_md());
235\& BIO_set_md(mdtmp, EVP_sha1());
236\& bio = BIO_push(mdtmp, bio);
237\& mdtmp = BIO_new(BIO_f_md());
238\& BIO_set_md(mdtmp, EVP_md5());
239\& bio = BIO_push(mdtmp, bio);
240\& do {
241\& rdlen = BIO_read(bio, buf, sizeof(buf));
242\& /* Might want to do something with the data here */
243\& } while(rdlen > 0);
244.Ve
245This next example retrieves the message digests from a \s-1BIO\s0 chain and
246outputs them. This could be used with the examples above.
247.PP
248.Vb 16
249\& BIO *mdtmp;
250\& unsigned char mdbuf[EVP_MAX_MD_SIZE];
251\& int mdlen;
252\& int i;
253\& mdtmp = bio; /* Assume bio has previously been set up */
254\& do {
255\& EVP_MD *md;
256\& mdtmp = BIO_find_type(mdtmp, BIO_TYPE_MD);
257\& if(!mdtmp) break;
258\& BIO_get_md(mdtmp, &md);
259\& printf("%s digest", OBJ_nid2sn(EVP_MD_type(md)));
260\& mdlen = BIO_gets(mdtmp, mdbuf, EVP_MAX_MD_SIZE);
261\& for(i = 0; i < mdlen; i++) printf(":%02X", mdbuf[i]);
262\& printf("\en");
263\& mdtmp = BIO_next(mdtmp);
264\& } while(mdtmp);
265.Ve
266.Vb 1
267\& BIO_free_all(bio);
268.Ve
269.SH "BUGS"
270.IX Header "BUGS"
271The lack of support for \fIBIO_puts()\fR and the non standard behaviour of
272\&\fIBIO_gets()\fR could be regarded as anomalous. It could be argued that \fIBIO_gets()\fR
273and \fIBIO_puts()\fR should be passed to the next \s-1BIO\s0 in the chain and digest
274the data passed through and that digests should be retrieved using a
275separate \fIBIO_ctrl()\fR call.
276.SH "SEE ALSO"
277.IX Header "SEE ALSO"
278\&\s-1TBA\s0
| 142.UC
143.SH "NAME"
144BIO_f_md, BIO_set_md, BIO_get_md, BIO_get_md_ctx \- message digest \s-1BIO\s0 filter
145.SH "SYNOPSIS"
146.IX Header "SYNOPSIS"
147.Vb 2
148\& #include <openssl/bio.h>
149\& #include <openssl/evp.h>
150.Ve
151.Vb 4
152\& BIO_METHOD * BIO_f_md(void);
153\& int BIO_set_md(BIO *b,EVP_MD *md);
154\& int BIO_get_md(BIO *b,EVP_MD **mdp);
155\& int BIO_get_md_ctx(BIO *b,EVP_MD_CTX **mdcp);
156.Ve
157.SH "DESCRIPTION"
158.IX Header "DESCRIPTION"
159\&\fIBIO_f_md()\fR returns the message digest \s-1BIO\s0 method. This is a filter
160\&\s-1BIO\s0 that digests any data passed through it, it is a \s-1BIO\s0 wrapper
161for the digest routines \fIEVP_DigestInit()\fR, \fIEVP_DigestUpdate()\fR
162and \fIEVP_DigestFinal()\fR.
163.PP
164Any data written or read through a digest \s-1BIO\s0 using \fIBIO_read()\fR and
165\&\fIBIO_write()\fR is digested.
166.PP
167\&\fIBIO_gets()\fR, if its \fBsize\fR parameter is large enough finishes the
168digest calculation and returns the digest value. \fIBIO_puts()\fR is
169not supported.
170.PP
171\&\fIBIO_reset()\fR reinitialises a digest \s-1BIO\s0.
172.PP
173\&\fIBIO_set_md()\fR sets the message digest of \s-1BIO\s0 \fBb\fR to \fBmd\fR: this
174must be called to initialize a digest \s-1BIO\s0 before any data is
175passed through it. It is a \fIBIO_ctrl()\fR macro.
176.PP
177\&\fIBIO_get_md()\fR places the a pointer to the digest BIOs digest method
178in \fBmdp\fR, it is a \fIBIO_ctrl()\fR macro.
179.PP
180\&\fIBIO_get_md_ctx()\fR returns the digest BIOs context into \fBmdcp\fR.
181.SH "NOTES"
182.IX Header "NOTES"
183The context returned by \fIBIO_get_md_ctx()\fR can be used in calls
184to \fIEVP_DigestFinal()\fR and also the signature routines \fIEVP_SignFinal()\fR
185and \fIEVP_VerifyFinal()\fR.
186.PP
187The context returned by \fIBIO_get_md_ctx()\fR is an internal context
188structure. Changes made to this context will affect the digest
189\&\s-1BIO\s0 itself and the context pointer will become invalid when the digest
190\&\s-1BIO\s0 is freed.
191.PP
192After the digest has been retrieved from a digest \s-1BIO\s0 it must be
193reinitialized by calling \fIBIO_reset()\fR, or \fIBIO_set_md()\fR before any more
194data is passed through it.
195.PP
196If an application needs to call \fIBIO_gets()\fR or \fIBIO_puts()\fR through
197a chain containing digest BIOs then this can be done by prepending
198a buffering \s-1BIO\s0.
199.SH "RETURN VALUES"
200.IX Header "RETURN VALUES"
201\&\fIBIO_f_md()\fR returns the digest \s-1BIO\s0 method.
202.PP
203\&\fIBIO_set_md()\fR, \fIBIO_get_md()\fR and \fIBIO_md_ctx()\fR return 1 for success and
2040 for failure.
205.SH "EXAMPLES"
206.IX Header "EXAMPLES"
207The following example creates a \s-1BIO\s0 chain containing an \s-1SHA1\s0 and \s-1MD5\s0
208digest \s-1BIO\s0 and passes the string \*(L"Hello World\*(R" through it. Error
209checking has been omitted for clarity.
210.PP
211.Vb 14
212\& BIO *bio, *mdtmp;
213\& char message[] = "Hello World";
214\& bio = BIO_new(BIO_s_null());
215\& mdtmp = BIO_new(BIO_f_md());
216\& BIO_set_md(mdtmp, EVP_sha1());
217\& /* For BIO_push() we want to append the sink BIO and keep a note of
218\& * the start of the chain.
219\& */
220\& bio = BIO_push(mdtmp, bio);
221\& mdtmp = BIO_new(BIO_f_md());
222\& BIO_set_md(mdtmp, EVP_md5());
223\& bio = BIO_push(mdtmp, bio);
224\& /* Note: mdtmp can now be discarded */
225\& BIO_write(bio, message, strlen(message));
226.Ve
227The next example digests data by reading through a chain instead:
228.PP
229.Vb 14
230\& BIO *bio, *mdtmp;
231\& char buf[1024];
232\& int rdlen;
233\& bio = BIO_new_file(file, "rb");
234\& mdtmp = BIO_new(BIO_f_md());
235\& BIO_set_md(mdtmp, EVP_sha1());
236\& bio = BIO_push(mdtmp, bio);
237\& mdtmp = BIO_new(BIO_f_md());
238\& BIO_set_md(mdtmp, EVP_md5());
239\& bio = BIO_push(mdtmp, bio);
240\& do {
241\& rdlen = BIO_read(bio, buf, sizeof(buf));
242\& /* Might want to do something with the data here */
243\& } while(rdlen > 0);
244.Ve
245This next example retrieves the message digests from a \s-1BIO\s0 chain and
246outputs them. This could be used with the examples above.
247.PP
248.Vb 16
249\& BIO *mdtmp;
250\& unsigned char mdbuf[EVP_MAX_MD_SIZE];
251\& int mdlen;
252\& int i;
253\& mdtmp = bio; /* Assume bio has previously been set up */
254\& do {
255\& EVP_MD *md;
256\& mdtmp = BIO_find_type(mdtmp, BIO_TYPE_MD);
257\& if(!mdtmp) break;
258\& BIO_get_md(mdtmp, &md);
259\& printf("%s digest", OBJ_nid2sn(EVP_MD_type(md)));
260\& mdlen = BIO_gets(mdtmp, mdbuf, EVP_MAX_MD_SIZE);
261\& for(i = 0; i < mdlen; i++) printf(":%02X", mdbuf[i]);
262\& printf("\en");
263\& mdtmp = BIO_next(mdtmp);
264\& } while(mdtmp);
265.Ve
266.Vb 1
267\& BIO_free_all(bio);
268.Ve
269.SH "BUGS"
270.IX Header "BUGS"
271The lack of support for \fIBIO_puts()\fR and the non standard behaviour of
272\&\fIBIO_gets()\fR could be regarded as anomalous. It could be argued that \fIBIO_gets()\fR
273and \fIBIO_puts()\fR should be passed to the next \s-1BIO\s0 in the chain and digest
274the data passed through and that digests should be retrieved using a
275separate \fIBIO_ctrl()\fR call.
276.SH "SEE ALSO"
277.IX Header "SEE ALSO"
278\&\s-1TBA\s0
|