1SSL_CTX_SET0_CA_LIST(3) OpenSSL SSL_CTX_SET0_CA_LIST(3)
2
6 SSL_CTX_set_client_CA_list, SSL_set_client_CA_list,
7 SSL_get_client_CA_list, SSL_CTX_get_client_CA_list,
8 SSL_CTX_add_client_CA, SSL_add_client_CA, SSL_set0_CA_list,
9 SSL_CTX_set0_CA_list, SSL_get0_CA_list, SSL_CTX_get0_CA_list,
10 SSL_add1_to_CA_list, SSL_CTX_add1_to_CA_list, SSL_get0_peer_CA_list -
11 get or set CA list
12
14 #include <openssl/ssl.h>
15 void SSL_CTX_set_client_CA_list(SSL_CTX *ctx, STACK_OF(X509_NAME) *list);
17 void SSL_set_client_CA_list(SSL *s, STACK_OF(X509_NAME) *list);
18 STACK_OF(X509_NAME) *SSL_get_client_CA_list(const SSL *s);
19 STACK_OF(X509_NAME) *SSL_CTX_get_client_CA_list(const SSL_CTX *ctx);
20 int SSL_CTX_add_client_CA(SSL_CTX *ctx, X509 *cacert);
21 int SSL_add_client_CA(SSL *ssl, X509 *cacert);
22 void SSL_CTX_set0_CA_list(SSL_CTX *ctx, STACK_OF(X509_NAME) *name_list);
24 void SSL_set0_CA_list(SSL *s, STACK_OF(X509_NAME) *name_list);
25 const STACK_OF(X509_NAME) *SSL_CTX_get0_CA_list(const SSL_CTX *ctx);
26 const STACK_OF(X509_NAME) *SSL_get0_CA_list(const SSL *s);
27 int SSL_CTX_add1_to_CA_list(SSL_CTX *ctx, const X509 *x);
28 int SSL_add1_to_CA_list(SSL *ssl, const X509 *x);
29 const STACK_OF(X509_NAME) *SSL_get0_peer_CA_list(const SSL *s);
31
33 The functions described here set and manage the list of CA names that
34 are sent between two communicating peers.
35 For TLS versions 1.2 and earlier the list of CA names is only sent from
37 the server to the client when requesting a client certificate. So any
38 list of CA names set is never sent from client to server and the list
39 of CA names retrieved by SSL_get0_peer_CA_list() is always NULL.
40 For TLS 1.3 the list of CA names is sent using the
42 certificate_authorities extension and may be sent by a client (in the
43 ClientHello message) or by a server (when requesting a certificate).
44 In most cases it is not necessary to set CA names on the client side.
46 The list of CA names that are acceptable to the client will be sent in
47 plaintext to the server. This has privacy implications and may also
48 have performance implications if the list is large. This optional
49 capability was introduced as part of TLSv1.3 and therefore setting CA
50 names on the client side will have no impact if that protocol version
51 has been disabled. Most servers do not need this and so this should be
52 avoided unless required.
53 The "client CA list" functions below only have an effect when called on
55 the server side.
56 SSL_CTX_set_client_CA_list() sets the list of CAs sent to the client
58 when requesting a client certificate for ctx. Ownership of list is
59 transferred to ctx and it should not be freed by the caller.
60 SSL_set_client_CA_list() sets the list of CAs sent to the client when
62 requesting a client certificate for the chosen ssl, overriding the
63 setting valid for ssl's SSL_CTX object. Ownership of list is
64 transferred to s and it should not be freed by the caller.
65 SSL_CTX_get_client_CA_list() returns the list of client CAs explicitly
67 set for ctx using SSL_CTX_set_client_CA_list(). The returned list
68 should not be freed by the caller.
69 SSL_get_client_CA_list() returns the list of client CAs explicitly set
71 for ssl using SSL_set_client_CA_list() or ssl's SSL_CTX object with
72 SSL_CTX_set_client_CA_list(), when in server mode. In client mode,
73 SSL_get_client_CA_list returns the list of client CAs sent from the
74 server, if any. The returned list should not be freed by the caller.
75 SSL_CTX_add_client_CA() adds the CA name extracted from cacert to the
77 list of CAs sent to the client when requesting a client certificate for
78 ctx.
79 SSL_add_client_CA() adds the CA name extracted from cacert to the list
81 of CAs sent to the client when requesting a client certificate for the
82 chosen ssl, overriding the setting valid for ssl's SSL_CTX object.
83 SSL_get0_peer_CA_list() retrieves the list of CA names (if any) the
85 peer has sent. This can be called on either the server or the client
86 side. The returned list should not be freed by the caller.
87 The "generic CA list" functions below are very similar to the "client
89 CA list" functions except that they have an effect on both the server
90 and client sides. The lists of CA names managed are separate - so you
91 cannot (for example) set CA names using the "client CA list" functions
92 and then get them using the "generic CA list" functions. Where a mix of
93 the two types of functions has been used on the server side then the
94 "client CA list" functions take precedence. Typically, on the server
95 side, the "client CA list " functions should be used in preference. As
96 noted above in most cases it is not necessary to set CA names on the
97 client side.
98 SSL_CTX_set0_CA_list() sets the list of CAs to be sent to the peer to
100 name_list. Ownership of name_list is transferred to ctx and it should
101 not be freed by the caller.
102 SSL_set0_CA_list() sets the list of CAs to be sent to the peer to
104 name_list overriding any list set in the parent SSL_CTX of s. Ownership
105 of name_list is transferred to s and it should not be freed by the
106 caller.
107 SSL_CTX_get0_CA_list() retrieves any previously set list of CAs set for
109 ctx. The returned list should not be freed by the caller.
110 SSL_get0_CA_list() retrieves any previously set list of CAs set for s
112 or if none are set the list from the parent SSL_CTX is retrieved. The
113 returned list should not be freed by the caller.
114 SSL_CTX_add1_to_CA_list() appends the CA subject name extracted from x
116 to the list of CAs sent to peer for ctx.
117 SSL_add1_to_CA_list() appends the CA subject name extracted from x to
119 the list of CAs sent to the peer for s, overriding the setting in the
120 parent SSL_CTX.
121
123 When a TLS/SSL server requests a client certificate (see
124 SSL_CTX_set_verify(3)), it sends a list of CAs, for which it will
125 accept certificates, to the client.
126 This list must explicitly be set using SSL_CTX_set_client_CA_list() or
128 SSL_CTX_set0_CA_list() for ctx and SSL_set_client_CA_list() or
129 SSL_set0_CA_list() for the specific ssl. The list specified overrides
130 the previous setting. The CAs listed do not become trusted (list only
131 contains the names, not the complete certificates); use
132 SSL_CTX_load_verify_locations(3) to additionally load them for
133 verification.
134 If the list of acceptable CAs is compiled in a file, the
136 SSL_load_client_CA_file(3) function can be used to help to import the
137 necessary data.
138 SSL_CTX_add_client_CA(), SSL_CTX_add1_to_CA_list(), SSL_add_client_CA()
140 and SSL_add1_to_CA_list() can be used to add additional items the list
141 of CAs. If no list was specified before using
142 SSL_CTX_set_client_CA_list(), SSL_CTX_set0_CA_list(),
143 SSL_set_client_CA_list() or SSL_set0_CA_list(), a new CA list for ctx
144 or ssl (as appropriate) is opened.
145
147 SSL_CTX_set_client_CA_list(), SSL_set_client_CA_list(),
148 SSL_CTX_set_client_CA_list(), SSL_set_client_CA_list(),
149 SSL_CTX_set0_CA_list() and SSL_set0_CA_list() do not return a value.
150 SSL_CTX_get_client_CA_list(), SSL_get_client_CA_list(),
152 SSL_CTX_get0_CA_list() and SSL_get0_CA_list() return a stack of CA
153 names or NULL is no CA names are set.
154 SSL_CTX_add_client_CA(),SSL_add_client_CA(), SSL_CTX_add1_to_CA_list()
156 and SSL_add1_to_CA_list() return 1 for success and 0 for failure.
157 SSL_get0_peer_CA_list() returns a stack of CA names sent by the peer or
159 NULL or an empty stack if no list was sent.
160
162 Scan all certificates in CAfile and list them as acceptable CAs:
163 SSL_CTX_set_client_CA_list(ctx, SSL_load_client_CA_file(CAfile));
165
167 ssl(7), SSL_load_client_CA_file(3), SSL_CTX_load_verify_locations(3)
168
170 Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
171 Licensed under the OpenSSL license (the "License"). You may not use
173 this file except in compliance with the License. You can obtain a copy
174 in the file LICENSE in the source distribution or at
175 <https://www.openssl.org/source/license.html>.
1761.1.1q 2022-07-07 SSL_CTX_SET0_CA_LIST(3)