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
|
.\" Automatically generated by Pod::Man 2.25 (Pod::Simple 3.28)
.\"
.\" 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" ''
'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.
.ie \nF \{\
. de IX
. tm Index:\\$1\t\\n%\t"\\$2"
..
. nr % 0
. rr F
.\}
.el \{\
. de IX
..
.\}
.\"
.\" 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 "SSL_CTX_set_max_cert_list 3"
.TH SSL_CTX_set_max_cert_list 3 "2014-01-06" "1.0.1f" "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"
SSL_CTX_set_max_cert_list, SSL_CTX_get_max_cert_list, SSL_set_max_cert_list, SSL_get_max_cert_list, \- manipulate allowed for the peer's certificate chain
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 1
\& #include <openssl/ssl.h>
\&
\& long SSL_CTX_set_max_cert_list(SSL_CTX *ctx, long size);
\& long SSL_CTX_get_max_cert_list(SSL_CTX *ctx);
\&
\& long SSL_set_max_cert_list(SSL *ssl, long size);
\& long SSL_get_max_cert_list(SSL *ctx);
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\fISSL_CTX_set_max_cert_list()\fR sets the maximum size allowed for the peer's
certificate chain for all \s-1SSL\s0 objects created from \fBctx\fR to be <size> bytes.
The \s-1SSL\s0 objects inherit the setting valid for \fBctx\fR at the time
\&\fISSL_new\fR\|(3) is being called.
.PP
\&\fISSL_CTX_get_max_cert_list()\fR returns the currently set maximum size for \fBctx\fR.
.PP
\&\fISSL_set_max_cert_list()\fR sets the maximum size allowed for the peer's
certificate chain for \fBssl\fR to be <size> bytes. This setting stays valid
until a new value is set.
.PP
\&\fISSL_get_max_cert_list()\fR returns the currently set maximum size for \fBssl\fR.
.SH "NOTES"
.IX Header "NOTES"
During the handshake process, the peer may send a certificate chain.
The \s-1TLS/SSL\s0 standard does not give any maximum size of the certificate chain.
The OpenSSL library handles incoming data by a dynamically allocated buffer.
In order to prevent this buffer from growing without bounds due to data
received from a faulty or malicious peer, a maximum size for the certificate
chain is set.
.PP
The default value for the maximum certificate chain size is 100kB (30kB
on the 16bit \s-1DOS\s0 platform). This should be sufficient for usual certificate
chains (OpenSSL's default maximum chain length is 10, see
\&\fISSL_CTX_set_verify\fR\|(3), and certificates
without special extensions have a typical size of 1\-2kB).
.PP
For special applications it can be necessary to extend the maximum certificate
chain size allowed to be sent by the peer, see e.g. the work on
\&\*(L"Internet X.509 Public Key Infrastructure Proxy Certificate Profile\*(R"
and \*(L"\s-1TLS\s0 Delegation Protocol\*(R" at http://www.ietf.org/ and
http://www.globus.org/ .
.PP
Under normal conditions it should never be necessary to set a value smaller
than the default, as the buffer is handled dynamically and only uses the
memory actually required by the data sent by the peer.
.PP
If the maximum certificate chain size allowed is exceeded, the handshake will
fail with a \s-1SSL_R_EXCESSIVE_MESSAGE_SIZE\s0 error.
.SH "RETURN VALUES"
.IX Header "RETURN VALUES"
\&\fISSL_CTX_set_max_cert_list()\fR and \fISSL_set_max_cert_list()\fR return the previously
set value.
.PP
\&\fISSL_CTX_get_max_cert_list()\fR and \fISSL_get_max_cert_list()\fR return the currently
set value.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fIssl\fR\|(3), \fISSL_new\fR\|(3),
\&\fISSL_CTX_set_verify\fR\|(3)
.SH "HISTORY"
.IX Header "HISTORY"
SSL*_set/\fIget_max_cert_list()\fR have been introduced in OpenSSL 0.9.7.
|