SRP module documentation

Signed-off-by: Antoine Salon <asalon@vmware.com>

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7522)

8 files changed, 466 insertions, 10 deletions

diff --git a/crypto/srp/srp_lib.c b/crypto/srp/srp_lib.c
index b97d630d37..a9e244ea91 100644
--- a/crypto/srp/srp_lib.c
+++ b/crypto/srp/srp_lib.c
@@ -44,13 +44,13 @@ static BIGNUM *srp_Calc_xy(const BIGNUM *x, const BIGNUM *y, const BIGNUM *N)
 
 static BIGNUM *srp_Calc_k(const BIGNUM *N, const BIGNUM *g)
 {
-    /* k = SHA1(N | PAD(g)) -- tls-srp draft 8 */
+    /* k = SHA1(N | PAD(g)) -- tls-srp RFC 5054 */
     return srp_Calc_xy(N, g, N);
 }
 
 BIGNUM *SRP_Calc_u(const BIGNUM *A, const BIGNUM *B, const BIGNUM *N)
 {
-    /* k = SHA1(PAD(A) || PAD(B) ) -- tls-srp draft 8 */
+    /* u = SHA1(PAD(A) || PAD(B) ) -- tls-srp RFC 5054 */
     return srp_Calc_xy(A, B, N);
 }
 
@@ -254,13 +254,13 @@ static SRP_gN knowngN[] = {
 
 /*
  * Check if G and N are known parameters. The values have been generated
- * from the ietf-tls-srp draft version 8
+ * from the IETF RFC 5054
  */
 char *SRP_check_known_gN_param(const BIGNUM *g, const BIGNUM *N)
 {
     size_t i;
     if ((g == NULL) || (N == NULL))
-        return 0;
+        return NULL;
 
     for (i = 0; i < KNOWN_GN_NUMBER; i++) {
         if (BN_cmp(knowngN[i].g, g) == 0 && BN_cmp(knowngN[i].N, N) == 0)
diff --git a/crypto/srp/srp_vfy.c b/crypto/srp/srp_vfy.c
index 17b35c00f9..622fffbcd0 100644
--- a/crypto/srp/srp_vfy.c
+++ b/crypto/srp/srp_vfy.c
@@ -340,12 +340,13 @@ static SRP_gN *SRP_get_gN_by_id(const char *id, STACK_OF(SRP_gN) *gN_tab)
     int i;
 
     SRP_gN *gN;
-    if (gN_tab != NULL)
+    if (gN_tab != NULL) {
         for (i = 0; i < sk_SRP_gN_num(gN_tab); i++) {
             gN = sk_SRP_gN_value(gN_tab, i);
             if (gN && (id == NULL || strcmp(gN->id, id) == 0))
                 return gN;
         }
+    }
 
     return SRP_get_default_gN(id);
 }
@@ -374,9 +375,13 @@ static BIGNUM *SRP_gN_place_bn(STACK_OF(SRP_gN_cache) *gN_cache, char *ch)
 }
 
 /*
- * this function parses verifier file. Format is:
- * string(index):base64(N):base64(g):0
- * string(username):base64(v):base64(salt):int(index)
+ * This function parses the verifier file generated by the srp app.
+ * The format for each entry is:
+ * V base64(verifier) base64(salt) username gNid userinfo(optional)
+ * or
+ * I base64(N) base64(g)
+ * Note that base64 is the SRP variant of base64 encoding described
+ * in t_fromb64().
  */
 
 int SRP_VBASE_init(SRP_VBASE *vb, char *verifier_file)
@@ -605,7 +610,7 @@ char *SRP_create_verifier(const char *user, const char *pass, char **salt,
         g_bn = g_bn_alloc;
         defgNid = "*";
     } else {
-        SRP_gN *gN = SRP_get_gN_by_id(g, NULL);
+        SRP_gN *gN = SRP_get_default_gN(g);
         if (gN == NULL)
             goto err;
         N_bn = gN->N;
diff --git a/doc/man1/srp.pod b/doc/man1/srp.pod
index e858a22260..4977431029 100644
--- a/doc/man1/srp.pod
+++ b/doc/man1/srp.pod
@@ -25,7 +25,7 @@ B<openssl srp>
 
 =head1 DESCRIPTION
 
-The B<srp> command is user to maintain an SRP (secure remote password)
+The B<srp> command is used to maintain an SRP (secure remote password)
 file.
 At most one of the B<-add>, B<-modify>, B<-delete>, and B<-list> options
 can be specified.
diff --git a/doc/man3/SRP_VBASE_new.pod b/doc/man3/SRP_VBASE_new.pod
new file mode 100644
index 0000000000..b235e58710
--- /dev/null
+++ b/doc/man3/SRP_VBASE_new.pod
@@ -0,0 +1,91 @@
+=pod
+
+=head1 NAME
+
+SRP_VBASE_new,
+SRP_VBASE_free,
+SRP_user_pwd_free,
+SRP_VBASE_init,
+SRP_VBASE_get1_by_user,
+SRP_VBASE_get_by_user
+- Functions to create and manage a stack of SRP user verifier information
+
+=head1 SYNOPSIS
+
+ #include <openssl/srp.h>
+
+ SRP_VBASE *SRP_VBASE_new(char *seed_key);
+ void SRP_VBASE_free(SRP_VBASE *vb);
+ void SRP_user_pwd_free(SRP_user_pwd *user_pwd);
+
+ int SRP_VBASE_init(SRP_VBASE *vb, char *verifier_file);
+
+ SRP_user_pwd *SRP_VBASE_get1_by_user(SRP_VBASE *vb, char *username);
+ SRP_user_pwd *SRP_VBASE_get_by_user(SRP_VBASE *vb, char *username);
+
+=head1 DESCRIPTION
+
+The SRP_VBASE_new() function allocates a structure to store server side SRP
+verifier information. If B<seed_key> is not NULL a copy is stored and used to
+generate dummy parameters for users that are not found by SRP_VBASE_get1_by_user().
+This allows the server to hide the fact that it doesn't have a verifier for a
+particular username, as described in section 2.5.1.3 'Unknown SRP' of RFC 5054.
+The seed string should contain random NUL terminated binary data (therefore
+the random data should not contain NUL bytes!).
+
+The SRP_VBASE_free() function frees up the B<vb> structure.
+If B<vb> is NULL, nothing is done.
+
+The SRP_user_pwd_free() function frees up the B<user_pwd> structure.
+If B<user_pwd> is NULL, nothing is done.
+
+The SRP_VBASE_init() function parses the information in a verifier file and
+populates the B<vb> structure.
+The verifier file is a text file containing multiple entries, whose format is:
+flag base64(verifier) base64(salt) username gNid userinfo(optional)
+where the flag can be 'V' (valid) or 'R' (revoked).
+Note that the base64 encoding used here is non-standard so it is recommended
+to use L<srp(1)> to generate this file.
+
+The SRP_VBASE_get1_by_user() function returns the password info for the user
+whose username matches B<username>. It replaces the deprecated
+SRP_VBASE_get_by_user().
+If no matching user is found but a seed_key and default gN parameters have been
+set, dummy authentication information is generated from the seed_key, allowing
+the server to hide the fact that it doesn't have a verifier for a particular
+username. When using SRP as a TLS authentication mechanism, this will cause
+the handshake to proceed normally but the first client will be rejected with
+a "bad_record_mac" alert, as if the password was incorrect.
+If no matching user is found and the seed_key is not set, NULL is returned.
+Ownership of the returned pointer is released to the caller, it must be freed
+with SRP_user_pwd_free().
+
+=head1 RETURN VALUES
+
+SRP_VBASE_init() returns B<SRP_NO_ERROR> (0) on success and a positive value
+on failure.
+The error codes are B<SRP_ERR_OPEN_FILE> if the file could not be opened,
+B<SRP_ERR_VBASE_INCOMPLETE_FILE> if the file could not be parsed,
+B<SRP_ERR_MEMORY> on memory allocation failure and B<SRP_ERR_VBASE_BN_LIB>
+for invalid decoded parameter values.
+
+=head1 SEE ALSO
+
+L<srp(1)>,
+L<SRP_create_verifier(3)>,
+L<SSL_CTX_set_srp_password(3)>
+
+=head1 HISTORY
+
+These functions were first added to OpenSSL 1.0.1.
+
+=head1 COPYRIGHT
+
+Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut
diff --git a/doc/man3/SRP_create_verifier.pod b/doc/man3/SRP_create_verifier.pod
new file mode 100644
index 0000000000..9741c5c47c
--- /dev/null
+++ b/doc/man3/SRP_create_verifier.pod
@@ -0,0 +1,115 @@
+=pod
+
+=head1 NAME
+
+SRP_create_verifier,
+SRP_create_verifier_BN,
+SRP_check_known_gN_param,
+SRP_get_default_gN
+- SRP authentication primitives
+
+=head1 SYNOPSIS
+
+ #include <openssl/srp.h>
+
+ char *SRP_create_verifier_BN(const char *user, const char *pass, BIGNUM **salt,
+                              BIGNUM **verifier, const BIGNUM *N, const BIGNUM *g);
+ char *SRP_create_verifier(const char *user, const char *pass, char **salt,
+                           char **verifier, const char *N, const char *g);
+
+ char *SRP_check_known_gN_param(const BIGNUM *g, const BIGNUM *N);
+ SRP_gN *SRP_get_default_gN(const char *id);
+
+=head1 DESCRIPTION
+
+The SRP_create_verifier_BN() function creates an SRP password verifier from
+the supplied parameters as defined in section 2.4 of RFC 5054.
+On successful exit B<*verifier> will point to a newly allocated BIGNUM containing
+the verifier and (if a salt was not provided) B<*salt> will be populated with a
+newly allocated BIGNUM containing a random salt. If B<*salt> is not NULL then
+the provided salt is used instead.
+The caller is responsible for freeing the allocated B<*salt> and B<*verifier>
+BIGNUMS (use L<BN_free(3)>).
+
+The SRP_create_verifier() function is similar to SRP_create_verifier_BN() but
+all numeric parameters are in a non-standard base64 encoding originally designed
+for compatibility with libsrp. This is mainly present for historical compatibility
+and its use is discouraged.
+It is possible to pass NULL as B<N> and an SRP group id as B<g> instead to
+load the appropriate gN values (see SRP_get_default_gN()).
+If both B<N> and B<g> are NULL the 8192-bit SRP group parameters are used.
+The caller is responsible for freeing the allocated *salt and *verifier char*
+(use L<OPENSSL_free(3)>).
+
+The SRP_check_known_gN_param() function checks that B<g> and B<N> are valid
+SRP group parameters from RFC 5054 appendix A.
+
+The SRP_get_default_gN() function returns the gN parameters for the RFC 5054 B<id>
+SRP group size.
+The known ids are "1024", "1536", "2048", "3072", "4096", "6144" and "8192".
+
+=head1 RETURN VALUES
+
+SRP_create_verifier_BN() returns 1 on success and 0 on failure.
+
+SRP_create_verifier() returns NULL on failure and a non-NULL value on success:
+"*" if B<N> is not NULL, the selected group id otherwise. This value should
+not be freed.
+
+SRP_check_known_gN_param() returns the text representation of the group id
+(ie. the prime bit size) or NULL if the arguments are not valid SRP group parameters.
+This value should not be freed.
+
+SRP_get_default_gN() returns NULL if B<id> is not a valid group size,
+or the 8192-bit group parameters if B<id> is NULL.
+
+=head1 EXAMPLES
+
+Generate and store a 8192 bit password verifier (error handling
+omitted for clarity):
+
+ #include <openssl/bn.h>
+ #include <openssl/srp.h>
+
+ const char *username = "username";
+ const char *password = "password";
+
+ SRP_VBASE *srpData = SRP_VBASE_new(NULL);
+
+ SRP_user_pwd *pwd = (SRP_user_pwd*) OPENSSL_malloc(sizeof(SRP_user_pwd));
+ SRP_gN *gN = SRP_get_default_gN("8192");
+
+ BIGNUM *salt = NULL, *verifier = NULL;
+ SRP_create_verifier_BN(username, password, &salt, &verifier, gN->N, gN->g);
+
+ // TODO: replace with SRP_user_pwd_new()
+ pwd->id = OPENSSL_strdup(username);
+ pwd->g = gN->g;
+ pwd->N = gN->N;
+ pwd->s = salt;
+ pwd->v = verifier;
+ pwd->info = NULL;
+
+ sk_SRP_user_pwd_push(srpData->users_pwd, pwd);
+
+=head1 SEE ALSO
+
+L<srp(1)>,
+L<BN_new(3)>,
+L<OPENSSL_malloc(3)>,
+L<SRP_VBASE_new(3)>
+
+=head1 HISTORY
+
+These functions were first added to OpenSSL 1.0.1.
+
+=head1 COPYRIGHT
+
+Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut
diff --git a/doc/man3/SSL_CTX_add_extra_chain_cert.pod b/doc/man3/SSL_CTX_add_extra_chain_cert.pod
index 6e429c31bd..b8f11b3a2d 100644
--- a/doc/man3/SSL_CTX_add_extra_chain_cert.pod
+++ b/doc/man3/SSL_CTX_add_extra_chain_cert.pod
@@ -26,9 +26,11 @@ after another.
 SSL_CTX_get_extra_chain_certs() retrieves the extra chain certificates
 associated with B<ctx>, or the chain associated with the current certificate
 of B<ctx> if the extra chain is empty.
+The returned stack should not be freed by the caller.
 
 SSL_CTX_get_extra_chain_certs_only() retrieves the extra chain certificates
 associated with B<ctx>.
+The returned stack should not be freed by the caller.
 
 SSL_CTX_clear_extra_chain_certs() clears all extra chain certificates
 associated with B<ctx>.
diff --git a/doc/man3/SSL_CTX_set_srp_password.pod b/doc/man3/SSL_CTX_set_srp_password.pod
new file mode 100644
index 0000000000..6f33230aaa
--- /dev/null
+++ b/doc/man3/SSL_CTX_set_srp_password.pod
@@ -0,0 +1,216 @@
+=pod
+
+=head1 NAME
+
+SSL_CTX_set_srp_username,
+SSL_CTX_set_srp_password,
+SSL_CTX_set_srp_strength,
+SSL_CTX_set_srp_cb_arg,
+SSL_CTX_set_srp_username_callback,
+SSL_CTX_set_srp_client_pwd_callback,
+SSL_CTX_set_srp_verify_param_callback,
+SSL_set_srp_server_param,
+SSL_set_srp_server_param_pw,
+SSL_get_srp_g,
+SSL_get_srp_N,
+SSL_get_srp_username,
+SSL_get_srp_userinfo
+- SRP control operations
+
+=head1 SYNOPSIS
+
+ #include <openssl/ssl.h>
+
+ int SSL_CTX_set_srp_username(SSL_CTX *ctx, char *name);
+ int SSL_CTX_set_srp_password(SSL_CTX *ctx, char *password);
+ int SSL_CTX_set_srp_strength(SSL_CTX *ctx, int strength);
+ int SSL_CTX_set_srp_cb_arg(SSL_CTX *ctx, void *arg);
+ int SSL_CTX_set_srp_username_callback(SSL_CTX *ctx,
+                                       int (*cb) (SSL *s, int *ad, void *arg));
+ int SSL_CTX_set_srp_client_pwd_callback(SSL_CTX *ctx,
+                                         char *(*cb) (SSL *s, void *arg));
+ int SSL_CTX_set_srp_verify_param_callback(SSL_CTX *ctx,
+                                           int (*cb) (SSL *s, void *arg));
+
+ int SSL_set_srp_server_param(SSL *s, const BIGNUM *N, const BIGNUM *g,
+                              BIGNUM *sa, BIGNUM *v, char *info);
+ int SSL_set_srp_server_param_pw(SSL *s, const char *user, const char *pass,
+                                 const char *grp);
+
+ BIGNUM *SSL_get_srp_g(SSL *s);
+ BIGNUM *SSL_get_srp_N(SSL *s);
+
+ char *SSL_get_srp_username(SSL *s);
+ char *SSL_get_srp_userinfo(SSL *s);
+
+=head1 DESCRIPTION
+
+These functions provide access to SRP (Secure Remote Password) parameters,
+an alternate authentication mechanism for TLS. SRP allows the use of user names
+and passwords over unencrypted channels without revealing the password to an
+eavesdropper. SRP also supplies a shared secret at the end of the authentication
+sequence that can be used to generate encryption keys.
+
+The SRP protocol, version 3 is specified in RFC 2945. SRP version 6 is described
+in RFC 5054 with applications to TLS authentication.
+
+The SSL_CTX_set_srp_username() function sets the SRP username for B<ctx>. This
+should be called on the client prior to creating a connection to the server.
+The length of B<name> must be shorter or equal to 255 characters.
+
+The SSL_CTX_set_srp_password() function sets the SRP password for B<ctx>. This
+may be called on the client prior to creating a connection to the server.
+This overrides the effect of SSL_CTX_set_srp_client_pwd_callback().
+
+The SSL_CTX_set_srp_strength() function sets the SRP strength for B<ctx>. This
+is the minimal length of the SRP prime in bits. If not specified 1024 is used.
+If not satisfied by the server key exchange the connection will be rejected.
+
+The SSL_CTX_set_srp_cb_arg() function sets an extra parameter that will
+be passed to all following callbacks as B<arg>.
+
+The SSL_CTX_set_srp_username_callback() function sets the server side callback
+that is invoked when an SRP username is found in a ClientHello.
+The callback parameters are the SSL connection B<s>, a writable error flag B<ad>
+and the extra argument B<arg> set by SSL_CTX_set_srp_cb_arg().
+This callback should setup the server for the key exchange by calling
+SSL_set_srp_server_param() with the appropriate parameters for the received
+username. The username can be obtained by calling SSL_get_srp_username().
+See L<SRP_VBASE_init(3)> to parse the verifier file created by L<srp(1)> or
+L<SRP_create_verifier(3)> to generate it.
+The callback should return B<SSL_ERROR_NONE> to proceed with the server key exchange,
+B<SSL3_AL_FATAL> for a fatal error or any value < 0 for a retryable error.
+In the event of a B<SSL3_AL_FATAL> the alert flag given by B<*al> will be sent
+back. By default this will be B<SSL_AD_UNKOWN_PSK_IDENTITY>.
+
+The SSL_CTX_set_srp_client_pwd_callback() function sets the client password
+callback on the client.
+The callback parameters are the SSL connection B<s> and the extra argument B<arg>
+set by SSL_CTX_set_srp_cb_arg().
+The callback will be called as part of the generation of the client secrets.
+It should return the client password in text form or NULL to abort the connection.
+The resulting memory will be freed by the library as part of the callback resolution.
+This overrides the effect of SSL_CTX_set_srp_password().
+
+The SSL_CTX_set_srp_verify_param_callback() sets the SRP gN parameter verification
+callback on the client. This allows the client to perform custom verification when
+receiving the server SRP proposed parameters.
+The callback parameters are the SSL connection B<s> and the extra argument B<arg>
+set by SSL_CTX_set_srp_cb_arg().
+The callback should return a positive value to accept the server parameters.
+Returning 0 or a negative value will abort the connection. The server parameters
+can be obtained by calling SSL_get_srp_N() and SSL_get_srp_g().
+Sanity checks are already performed by the library after the handshake
+(B % N non zero, check against the strength parameter) and are not necessary.
+If no callback is set the g and N parameters will be checked against
+known RFC 5054 values.
+
+The SSL_set_srp_server_param() function sets all SRP parameters for
+the connection B<s>. B<N> and B<g> are the SRP group parameters, B<sa> is the
+user salt, B<v> the password verifier and B<info> is the optional user info.
+
+The SSL_set_srp_server_param_pw() function sets all SRP parameters for the
+connection B<s> by generating a random salt and a password verifier.
+B<user> is the username, B<pass> the password and B<grp> the SRP group paramters
+identifier for L<SRP_get_default_gN(3)>.
+
+The SSL_get_srp_g() function returns the SRP group generator for B<s>, or from
+the underlying SSL_CTX if it is NULL.
+
+The SSL_get_srp_N() function returns the SRP prime for B<s>, or from
+the underlying SSL_CTX if it is NULL.
+
+The SSL_get_srp_username() function returns the SRP username for B<s>, or from
+the underlying SSL_CTX if it is NULL.
+
+The SSL_get_srp_userinfo() function returns the SRP user info for B<s>, or from
+the underlying SSL_CTX if it is NULL.
+
+=head1 RETURN VALUES
+
+All SSL_CTX_set_* functions return 1 on success and 0 on failure.
+
+SSL_set_srp_server_param() returns 1 on success and -1 on failure.
+
+The SSL_get_SRP_* functions return a pointer to the requested data, the memory
+is owned by the library and should not be freed by the caller.
+
+=head1 EXAMPLES
+
+Setup SRP parameters on the client:
+
+ #include <openssl/ssl.h>
+
+ const char *username = "username";
+ const char *password = "password";
+
+ SSL_CTX *ctx = SSL_CTX_new(TLS_client_method());
+ if (!ctx)
+     /* Error */
+ if (!SSL_CTX_set_srp_username(ctx, username))
+     /* Error */
+ if (!SSL_CTX_set_srp_password(ctx, password))
+     /* Error */
+
+Setup SRP server with verifier file:
+
+ #include <openssl/srp.h>
+ #include <openssl/ssl.h>
+
+ const char *srpvfile = "password.srpv";
+
+ int srpServerCallback(SSL *s, int *ad, void *arg)
+ {
+     SRP_VBASE *srpData = (SRP_VBASE*) arg;
+     char *username = SSL_get_srp_username(s);
+
+     SRP_user_pwd *user_pwd = SRP_VBASE_get1_by_user(srpData, username);
+     if (!user_pwd)
+         /* Error */
+         return SSL3_AL_FATAL;
+
+     if (SSL_set_srp_server_param(s, user_pwd->N, user_pwd->g,
+         user_pwd->s, user_pwd->v, user_pwd->info) < 0)
+         /* Error */
+
+     SRP_user_pwd_free(user_pwd);
+     return SSL_ERROR_NONE;
+ }
+
+ SSL_CTX *ctx = SSL_CTX_new(TLS_server_method());
+ if (!ctx)
+     /* Error */
+
+ /*
+  * seedKey should contain a NUL terminated sequence
+  * of random non NUL bytes
+  */
+ const char *seedKey;
+
+ SRP_VBASE *srpData = SRP_VBASE_new(seedKey);
+ if (SRP_VBASE_init(srpData, (char*) srpvfile) != SRP_NO_ERROR)
+    /* Error */
+
+ SSL_CTX_set_srp_cb_arg(ctx, srpData);
+ SSL_CTX_set_srp_username_callback(ctx, srpServerCallback);
+
+=head1 SEE ALSO
+
+L<srp(1)>,
+L<SRP_VBASE_new(3)>,
+L<SRP_create_verifier(3)>
+
+=head1 HISTORY
+
+These functions were first added to OpenSSL 1.0.1.
+
+=head1 COPYRIGHT
+
+Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut
diff --git a/doc/man7/ssl.pod b/doc/man7/ssl.pod
index 1695f7ea19..60b1834f98 100644
--- a/doc/man7/ssl.pod
+++ b/doc/man7/ssl.pod
@@ -375,6 +375,20 @@ Use the file path to locate trusted CA certificates.
 
 =item void B<SSL_CTX_set_session_cache_mode>(SSL_CTX *ctx, int mode);
 
+=item int B<SSL_CTX_set_srp_cb_arg>(SSL_CTX *ctx, void *arg);
+
+=item int B<SSL_CTX_set_srp_client_pwd_callback>(SSL_CTX *ctx, char *(*cb)(SSL *ssl, void *arg));
+
+=item int B<SSL_CTX_set_srp_password>(SSL_CTX *ctx, char *password);
+
+=item int B<SSL_CTX_set_srp_strength>(SSL_CTX *ctx, int strength);
+
+=item int B<SSL_CTX_set_srp_username>(SSL_CTX *ctx, char *name);
+
+=item int B<SSL_CTX_set_srp_username_callback>(SSL_CTX *ctx, int (*cb)(SSL *ssl, int *ad, void *arg));
+
+=item int B<SSL_CTX_set_srp_verify_param_callback>(SSL_CTX *ctx, int (*cb)(SSL *ssl, void *arg));
+
 =item int B<SSL_CTX_set_ssl_version>(SSL_CTX *ctx, const SSL_METHOD *meth);
 
 =item void B<SSL_CTX_set_timeout>(SSL_CTX *ctx, long t);
@@ -582,6 +596,14 @@ fresh handle for each connection.
 
 =item int B<SSL_get_shutdown>(const SSL *ssl);
 
+=item BIGNUM *B<SSL_get_srp_g>(SSL *ssl);
+
+=item BIGNUM *B<SSL_get_srp_N>(SSL *ssl);
+
+=item char *B<SSL_get_srp_userinfo>(SSL *ssl);
+
+=item char *B<SSL_get_srp_username>(SSL *ssl);
+
 =item const SSL_METHOD *B<SSL_get_ssl_method>(SSL *ssl);
 
 =item int B<SSL_get_state>(const SSL *ssl);
@@ -674,6 +696,10 @@ fresh handle for each connection.
 
 =item void B<SSL_set_shutdown>(SSL *ssl, int mode);
 
+=item int B<SSL_set_srp_server_param>(SSL *ssl, const BIGNUM *N, const BIGNUM *g, BIGNUM *sa, BIGNUM *v, char *info);
+
+=item int B<SSL_set_srp_server_param_pw>(SSL *ssl, const char *user, const char *pass, const char *grp);
+
 =item int B<SSL_set_ssl_method>(SSL *ssl, const SSL_METHOD *meth);
 
 =item void B<SSL_set_time>(SSL *ssl, long t);
@@ -790,6 +816,7 @@ L<SSL_CTX_set_read_ahead(3)>,
 L<SSL_CTX_set_security_level(3)>,
 L<SSL_CTX_set_session_cache_mode(3)>,
 L<SSL_CTX_set_session_id_context(3)>,
+L<SSL_CTX_set_srp_password(3)>,
 L<SSL_CTX_set_ssl_version(3)>,
 L<SSL_CTX_set_timeout(3)>,
 L<SSL_CTX_set_tmp_dh_callback(3)>,