1=pod 2 3=head1 NAME 4 5SSL_CTX_set0_chain, SSL_CTX_set1_chain, SSL_CTX_add0_chain_cert, 6SSL_CTX_add1_chain_cert, SSL_CTX_get0_chain_certs, SSL_CTX_clear_chain_certs, 7SSL_set0_chain, SSL_set1_chain, SSL_add0_chain_cert, SSL_add1_chain_cert, 8SSL_get0_chain_certs, SSL_clear_chain_certs, SSL_CTX_build_cert_chain, 9SSL_build_cert_chain, SSL_CTX_select_current_cert, 10SSL_select_current_cert, SSL_CTX_set_current_cert, SSL_set_current_cert - extra 11chain certificate processing 12 13=head1 SYNOPSIS 14 15 #include <openssl/ssl.h> 16 17 int SSL_CTX_set0_chain(SSL_CTX *ctx, STACK_OF(X509) *sk); 18 int SSL_CTX_set1_chain(SSL_CTX *ctx, STACK_OF(X509) *sk); 19 int SSL_CTX_add0_chain_cert(SSL_CTX *ctx, X509 *x509); 20 int SSL_CTX_add1_chain_cert(SSL_CTX *ctx, X509 *x509); 21 int SSL_CTX_get0_chain_certs(SSL_CTX *ctx, STACK_OF(X509) **sk); 22 int SSL_CTX_clear_chain_certs(SSL_CTX *ctx); 23 24 int SSL_set0_chain(SSL *ssl, STACK_OF(X509) *sk); 25 int SSL_set1_chain(SSL *ssl, STACK_OF(X509) *sk); 26 int SSL_add0_chain_cert(SSL *ssl, X509 *x509); 27 int SSL_add1_chain_cert(SSL *ssl, X509 *x509); 28 int SSL_get0_chain_certs(SSL *ssl, STACK_OF(X509) **sk); 29 int SSL_clear_chain_certs(SSL *ssl); 30 31 int SSL_CTX_build_cert_chain(SSL_CTX *ctx, flags); 32 int SSL_build_cert_chain(SSL *ssl, flags); 33 34 int SSL_CTX_select_current_cert(SSL_CTX *ctx, X509 *x509); 35 int SSL_select_current_cert(SSL *ssl, X509 *x509); 36 int SSL_CTX_set_current_cert(SSL_CTX *ctx, long op); 37 int SSL_set_current_cert(SSL *ssl, long op); 38 39=head1 DESCRIPTION 40 41SSL_CTX_set0_chain() and SSL_CTX_set1_chain() set the certificate chain 42associated with the current certificate of B<ctx> to B<sk>. 43 44SSL_CTX_add0_chain_cert() and SSL_CTX_add1_chain_cert() append the single 45certificate B<x509> to the chain associated with the current certificate of 46B<ctx>. 47 48SSL_CTX_get0_chain_certs() retrieves the chain associated with the current 49certificate of B<ctx>. 50 51SSL_CTX_clear_chain_certs() clears any existing chain associated with the 52current certificate of B<ctx>. (This is implemented by calling 53SSL_CTX_set0_chain() with B<sk> set to B<NULL>). 54 55SSL_CTX_build_cert_chain() builds the certificate chain for B<ctx> normally 56this uses the chain store or the verify store if the chain store is not set. 57If the function is successful the built chain will replace any existing chain. 58The B<flags> parameter can be set to B<SSL_BUILD_CHAIN_FLAG_UNTRUSTED> to use 59existing chain certificates as untrusted CAs, B<SSL_BUILD_CHAIN_FLAG_NO_ROOT> 60to omit the root CA from the built chain, B<SSL_BUILD_CHAIN_FLAG_CHECK> to 61use all existing chain certificates only to build the chain (effectively 62sanity checking and rearranging them if necessary), the flag 63B<SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR> ignores any errors during verification: 64if flag B<SSL_BUILD_CHAIN_FLAG_CLEAR_ERROR> is also set verification errors 65are cleared from the error queue. 66 67Each of these functions operates on the I<current> end entity 68(i.e. server or client) certificate. This is the last certificate loaded or 69selected on the corresponding B<ctx> structure. 70 71SSL_CTX_select_current_cert() selects B<x509> as the current end entity 72certificate, but only if B<x509> has already been loaded into B<ctx> using a 73function such as SSL_CTX_use_certificate(). 74 75SSL_set0_chain(), SSL_set1_chain(), SSL_add0_chain_cert(), 76SSL_add1_chain_cert(), SSL_get0_chain_certs(), SSL_clear_chain_certs(), 77SSL_build_cert_chain(), SSL_select_current_cert() and SSL_set_current_cert() 78are similar except they apply to SSL structure B<ssl>. 79 80SSL_CTX_set_current_cert() changes the current certificate to a value based 81on the B<op> argument. Currently B<op> can be B<SSL_CERT_SET_FIRST> to use 82the first valid certificate or B<SSL_CERT_SET_NEXT> to set the next valid 83certificate after the current certificate. These two operations can be 84used to iterate over all certificates in an B<SSL_CTX> structure. 85 86SSL_set_current_cert() also supports the option B<SSL_CERT_SET_SERVER>. 87If B<ssl> is a server and has sent a certificate to a connected client 88this option sets that certificate to the current certificate and returns 1. 89If the negotiated cipher suite is anonymous (and thus no certificate will 90be sent) 2 is returned and the current certificate is unchanged. If B<ssl> 91is not a server or a certificate has not been sent 0 is returned and 92the current certificate is unchanged. 93 94All these functions are implemented as macros. Those containing a B<1> 95increment the reference count of the supplied certificate or chain so it must 96be freed at some point after the operation. Those containing a B<0> do 97not increment reference counts and the supplied certificate or chain 98B<MUST NOT> be freed after the operation. 99 100=head1 NOTES 101 102The chains associate with an SSL_CTX structure are copied to any SSL 103structures when SSL_new() is called. SSL structures will not be affected 104by any chains subsequently changed in the parent SSL_CTX. 105 106One chain can be set for each key type supported by a server. So, for example, 107an RSA and a DSA certificate can (and often will) have different chains. 108 109The functions SSL_CTX_build_cert_chain() and SSL_build_cert_chain() can 110be used to check application configuration and to ensure any necessary 111subordinate CAs are sent in the correct order. Misconfigured applications 112sending incorrect certificate chains often cause problems with peers. 113 114For example an application can add any set of certificates using 115SSL_CTX_use_certificate_chain_file() then call SSL_CTX_build_cert_chain() 116with the option B<SSL_BUILD_CHAIN_FLAG_CHECK> to check and reorder them. 117 118Applications can issue non fatal warnings when checking chains by setting 119the flag B<SSL_BUILD_CHAIN_FLAG_IGNORE_ERRORS> and checking the return 120value. 121 122Calling SSL_CTX_build_cert_chain() or SSL_build_cert_chain() is more 123efficient than the automatic chain building as it is only performed once. 124Automatic chain building is performed on each new session. 125 126If any certificates are added using these functions no certificates added 127using SSL_CTX_add_extra_chain_cert() will be used. 128 129=head1 RETURN VALUES 130 131SSL_set_current_cert() with B<SSL_CERT_SET_SERVER> return 1 for success, 2 if 132no server certificate is used because the cipher suites is anonymous and 0 133for failure. 134 135SSL_CTX_build_cert_chain() and SSL_build_cert_chain() return 1 for success 136and 0 for failure. If the flag B<SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR> and 137a verification error occurs then 2 is returned. 138 139All other functions return 1 for success and 0 for failure. 140 141=head1 SEE ALSO 142 143L<SSL_CTX_add_extra_chain_cert(3)> 144 145=head1 HISTORY 146 147These functions were added in OpenSSL 1.0.2. 148 149=head1 COPYRIGHT 150 151Copyright 2013-2016 The OpenSSL Project Authors. All Rights Reserved. 152 153Licensed under the OpenSSL license (the "License"). You may not use 154this file except in compliance with the License. You can obtain a copy 155in the file LICENSE in the source distribution or at 156L<https://www.openssl.org/source/license.html>. 157 158=cut 159