/*
* Copyright 2004-2018 The OpenSSL Project Authors. All Rights Reserved.
* Copyright (c) 2004, EdelKey Project. 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
* https://www.openssl.org/source/license.html
*
* Originally written by Christophe Renou and Peter Sylvester,
* for the EdelKey project.
*/
#include <openssl/crypto.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#include "ssl_local.h"
#ifndef OPENSSL_NO_SRP
# include <openssl/srp.h>
int SSL_CTX_SRP_CTX_free(struct ssl_ctx_st *ctx)
{
if (ctx == NULL)
return 0;
OPENSSL_free(ctx->srp_ctx.login);
OPENSSL_free(ctx->srp_ctx.info);
BN_free(ctx->srp_ctx.N);
BN_free(ctx->srp_ctx.g);
BN_free(ctx->srp_ctx.s);
BN_free(ctx->srp_ctx.B);
BN_free(ctx->srp_ctx.A);
BN_free(ctx->srp_ctx.a);
BN_free(ctx->srp_ctx.b);
BN_free(ctx->srp_ctx.v);
memset(&ctx->srp_ctx, 0, sizeof(ctx->srp_ctx));
ctx->srp_ctx.strength = SRP_MINIMAL_N;
return 1;
}
int SSL_SRP_CTX_free(struct ssl_st *s)
{
if (s == NULL)
return 0;
OPENSSL_free(s->srp_ctx.login);
OPENSSL_free(s->srp_ctx.info);
BN_free(s->srp_ctx.N);
BN_free(s->srp_ctx.g);
BN_free(s->srp_ctx.s);
BN_free(s->srp_ctx.B);
BN_free(s->srp_ctx.A);
BN_free(s->srp_ctx.a);
BN_free(s->srp_ctx.b);
BN_free(s->srp_ctx.v);
memset(&s->srp_ctx, 0, sizeof(s->srp_ctx));
s->srp_ctx.strength = SRP_MINIMAL_N;
return 1;
}
int SSL_SRP_CTX_init(struct ssl_st *s)
{
SSL_CTX *ctx;
if ((s == NULL) || ((ctx = s->ctx) == NULL))
return 0;
memset(&s->srp_ctx, 0, sizeof(s->srp_ctx));
s->srp_ctx.SRP_cb_arg = ctx->srp_ctx.SRP_cb_arg;
/* set client Hello login callback */
s->srp_ctx.TLS_ext_srp_username_callback =
ctx->srp_ctx.TLS_ext_srp_username_callback;
/* set SRP N/g param callback for verification */
s->srp_ctx.SRP_verify_param_callback =
ctx->srp_ctx.SRP_verify_param_callback;
/* set SRP client passwd callback */
s->srp_ctx.SRP_give_srp_client_pwd_callback =
ctx->srp_ctx.SRP_give_srp_client_pwd_callback;
s->srp_ctx.strength = ctx->srp_ctx.strength;
if (((ctx->srp_ctx.N != NULL) &&
((s->srp_ctx.N = BN_dup(ctx->srp_ctx.N)) == NULL)) ||
((ctx->srp_ctx.g != NULL) &&
((s->srp_ctx.g = BN_dup(ctx->srp_ctx.g)) == NULL)) ||
((ctx->srp_ctx.s != NULL) &&
((s->srp_ctx.s = BN_dup(ctx->srp_ctx.s)) == NULL)) ||
((ctx->srp_ctx.B != NULL) &&
((s->srp_ctx.B = BN_dup(ctx->srp_ctx.B)) == NULL)) ||
((ctx->srp_ctx.A != NULL) &&
((s->srp_ctx.A = BN_dup(ctx->srp_ctx.A)) == NULL)) ||
((ctx->srp_ctx.a != NULL) &&
((s->srp_ctx.a = BN_dup(ctx->srp_ctx.a)) == NULL)) ||
((ctx->srp_ctx.v != NULL) &&
((s->srp_ctx.v = BN_dup(ctx->srp_ctx.v)) == NULL)) ||
((ctx->srp_ctx.b != NULL) &&
((s->srp_ctx.b = BN_dup(ctx->srp_ctx.b)) == NULL))) {
SSLerr(SSL_F_SSL_SRP_CTX_INIT, ERR_R_BN_LIB);
goto err;
}
if ((ctx->srp_ctx.login != NULL) &&
((s->srp_ctx.login = OPENSSL_strdup(ctx->srp_ctx.login)) == NULL)) {
SSLerr(SSL_F_SSL_SRP_CTX_INIT, ERR_R_INTERNAL_ERROR);
goto err;
}
if ((ctx->srp_ctx.info != NULL) &&
((s->srp_ctx.info = BUF_strdup(ctx->srp_ctx.info)) == NULL)) {
SSLerr(SSL_F_SSL_SRP_CTX_INIT, ERR_R_INTERNAL_ERROR);
goto err;
}
s->srp_ctx.srp_Mask = ctx->srp_ctx.srp_Mask;
return 1;
err:
OPENSSL_free(s->srp_ctx.login);
OPENSSL_free(s->srp_ctx.info);
BN_free(s->srp_ctx.N);
BN_free(s->srp_ctx.g);
BN_free(s->srp_ctx.s);
BN_free(s->srp_ctx.B);
BN_free(s->srp_ctx.A);
BN_free(s->srp_ctx.a);
BN_free(s->srp_ctx.b);
BN_free(s->srp_ctx.v);
memset(&s->srp_ctx, 0, sizeof(s->srp_ctx));
return 0;
}
int SSL_CTX_SRP_CTX_init(struct ssl_ctx_st *ctx)
{
if (ctx == NULL)
return 0;
memset(&ctx->srp_ctx, 0, sizeof(ctx->srp_ctx));
ctx->srp_ctx.strength = SRP_MINIMAL_N;
return 1;
}
/* server side */
int SSL_srp_server_param_with_username(SSL *s, int *ad)
{
unsigned char b[SSL_MAX_MASTER_KEY_LENGTH];
int al;
*ad = SSL_AD_UNKNOWN_PSK_IDENTITY;
if ((s->srp_ctx.TLS_ext_srp_username_callback != NULL) &&
((al =
s->srp_ctx.TLS_ext_srp_username_callback(s, ad,
s->srp_ctx.SRP_cb_arg)) !=
SSL_ERROR_NONE))
return al;
*ad = SSL_AD_INTERNAL_ERROR;
if ((s->srp_ctx.N == NULL) ||
(s->srp_ctx.g == NULL) ||
(s->srp_ctx.s == NULL) || (s->srp_ctx.v == NULL))
return SSL3_AL_FATAL;
if (RAND_priv_bytes(b, sizeof(b)) <= 0)
return SSL3_AL_FATAL;
s->srp_ctx.b = BN_bin2bn(b, sizeof(b), NULL);
OPENSSL_cleanse(b, sizeof(b));
/* Calculate: B = (kv + g^b) % N */
return ((s->srp_ctx.B =
SRP_Calc_B(s->srp_ctx.b, s->srp_ctx.N, s->srp_ctx.g,
s->srp_ctx.v)) !=
NULL) ? SSL_ERROR_NONE : SSL3_AL_FATAL;
}
/*
* If the server just has the raw password, make up a verifier entry on the
* fly
*/
int SSL_set_srp_server_param_pw(SSL *s, const char *user, const char *pass,
const char *grp)
{
SRP_gN *GN = SRP_get_default_gN(grp);
if (GN == NULL)
return -1;
s->srp_ctx.N = BN_dup(GN->N);
s->srp_ctx.g = BN_dup(GN->g);
BN_clear_free(s->srp_ctx.v);
s->srp_ctx.v = NULL;
BN_clear_free(s->srp_ctx.s);
s->srp_ctx.s = NULL;
if (!SRP_create_verifier_BN
(user, pass, &s->srp_ctx.s, &s->srp_ctx.v, GN->N, GN->g))
return -1;
return 1;
}
int SSL_set_srp_server_param(SSL *s, const BIGNUM *N, const BIGNUM *g,
BIGNUM *sa, BIGNUM *v, char *info)
{
if (N != NULL) {
if (s->srp_ctx.N != NULL) {
if (!BN_copy(s->srp_ctx.N, N)) {
BN_free(s->srp_ctx.N);
s->srp_ctx.N = NULL;
}
} else
s->srp_ctx.N = BN_dup(N);
}
if (g != NULL) {
if (s->srp_ctx.g != NULL) {
if (!BN_copy(s->srp_ctx.g, g)) {
BN_free(s->srp_ctx.g);
s->srp_ctx.g = NULL;
}
} else
s->srp_ctx.g = BN_dup(g);
}
if (sa != NULL) {
if (s->srp_ctx.s != NULL) {
if (!BN_copy(s->srp_ctx.s, sa)) {
BN_free(s->srp_ctx.s);
s->srp_ctx.s = NULL;
}
} else
s->srp_ctx.s = BN_dup(sa);
}
if (v != NULL) {
if (s->srp_ctx.v != NULL) {
if (!BN_copy(s->srp_ctx.v, v)) {
BN_free(s->srp_ctx.v);
s->srp_ctx.v = NULL;
}
} else
s->srp_ctx.v = BN_dup(v);
}
if (info != NULL) {
if (s->srp_ctx.info)
OPENSSL_free(s->srp_ctx.info);
if ((s->srp_ctx.info = BUF_strdup(info)) == NULL)
return -1;
}
if (!(s->srp_ctx.N) ||
!(s->srp_ctx.g) || !(s->srp_ctx.s) || !(s->srp_ctx.v))
return -1;
return 1;
}
int srp_generate_server_master_secret(SSL *s)
{
BIGNUM *K = NULL, *u = NULL;
int ret = -1, tmp_len = 0;
unsigned char *tmp = NULL;
if (!SRP_Verify_A_mod_N(s->srp_ctx.A, s->srp_ctx.N))
goto err;
if ((u = SRP_Calc_u(s->srp_ctx.A, s->srp_ctx.B, s->srp_ctx.N)) == NULL)
goto err;
if ((K = SRP_Calc_server_key(s->srp_ctx.A, s->srp_ctx.v, u, s->srp_ctx.b,
s->srp_ctx.N)) == NULL)
goto err;
tmp_len = BN_num_bytes(K);
if ((tmp = OPENSSL_malloc(tmp_len)) == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_SRP_GENERATE_SERVER_MASTER_SECRET, ERR_R_MALLOC_FAILURE);
goto err;
}
BN_bn2bin(K, tmp);
/* Calls SSLfatal() as required */
ret = ssl_generate_master_secret(s, tmp, tmp_len, 1);
err:
BN_clear_free(K);
BN_clear_free(u);
return ret;
}
/* client side */
int srp_generate_client_master_secret(SSL *s)
{
BIGNUM *x = NULL, *u = NULL, *K = NULL;
int ret = -1, tmp_len = 0;
char *passwd = NULL;
unsigned char *tmp = NULL;
/*
* Checks if b % n == 0
*/
if (SRP_Verify_B_mod_N(s->srp_ctx.B, s->srp_ctx.N) == 0
|| (u = SRP_Calc_u(s->srp_ctx.A, s->srp_ctx.B, s->srp_ctx.N))
== NULL
|| s->srp_ctx.SRP_give_srp_client_pwd_callback == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_SRP_GENERATE_CLIENT_MASTER_SECRET, ERR_R_INTERNAL_ERROR);
goto err;
}
if ((passwd = s->srp_ctx.SRP_give_srp_client_pwd_callback(s,
s->srp_ctx.SRP_cb_arg))
== NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_SRP_GENERATE_CLIENT_MASTER_SECRET,
SSL_R_CALLBACK_FAILED);
goto err;
}
if ((x = SRP_Calc_x(s->srp_ctx.s, s->srp_ctx.login, passwd)) == NULL
|| (K = SRP_Calc_client_key(s->srp_ctx.N, s->srp_ctx.B,
s->srp_ctx.g, x,
s->srp_ctx.a, u)) == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_SRP_GENERATE_CLIENT_MASTER_SECRET, ERR_R_INTERNAL_ERROR);
goto err;
}
tmp_len = BN_num_bytes(K);
if ((tmp = OPENSSL_malloc(tmp_len)) == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_SRP_GENERATE_CLIENT_MASTER_SECRET, ERR_R_MALLOC_FAILURE);
goto err;
}
BN_bn2bin(K, tmp);
/* Calls SSLfatal() as required */
ret = ssl_generate_master_secret(s, tmp, tmp_len, 1);
err:
BN_clear_free(K);
BN_clear_free(x);
if (passwd != NULL)
OPENSSL_clear_free(passwd, strlen(passwd));
BN_clear_free(u);
return ret;
}
int srp_verify_server_param(SSL *s)
{
SRP_CTX *srp = &s->srp_ctx;
/*
* Sanity check parameters: we can quickly check B % N == 0 by checking B
* != 0 since B < N
*/
if (BN_ucmp(srp->g, srp->N) >= 0 || BN_ucmp(srp->B, srp->N) >= 0
|| BN_is_zero(srp->B)) {
SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SRP_VERIFY_SERVER_PARAM,
SSL_R_BAD_DATA);
return 0;
}
if (BN_num_bits(srp->N) < srp->strength) {
SSLfatal(s, SSL_AD_INSUFFICIENT_SECURITY, SSL_F_SRP_VERIFY_SERVER_PARAM,
SSL_R_INSUFFICIENT_SECURITY);
return 0;
}
if (srp->SRP_verify_param_callback) {
if (srp->SRP_verify_param_callback(s, srp->SRP_cb_arg) <= 0) {
SSLfatal(s, SSL_AD_INSUFFICIENT_SECURITY,
SSL_F_SRP_VERIFY_SERVER_PARAM,
SSL_R_CALLBACK_FAILED);
return 0;
}
} else if (!SRP_check_known_gN_param(srp->g, srp->N)) {
SSLfatal(s, SSL_AD_INSUFFICIENT_SECURITY, SSL_F_SRP_VERIFY_SERVER_PARAM,
SSL_R_INSUFFICIENT_SECURITY);
return 0;
}
return 1;
}
int SRP_Calc_A_param(SSL *s)
{
unsigned char rnd[SSL_MAX_MASTER_KEY_LENGTH];
if (RAND_priv_bytes(rnd, sizeof(rnd)) <= 0)
return 0;
s->srp_ctx.a = BN_bin2bn(rnd, sizeof(rnd), s->srp_ctx.a);
OPENSSL_cleanse(rnd, sizeof(rnd));
if (!(s->srp_ctx.A = SRP_Calc_A(s->srp_ctx.a, s->srp_ctx.N, s->srp_ctx.g)))
return 0;
return 1;
}
BIGNUM *SSL_get_srp_g(SSL *s)
{
if (s->srp_ctx.g != NULL)
return s->srp_ctx.g;
return s->ctx->srp_ctx.g;
}
BIGNUM *SSL_get_srp_N(SSL *s)
{
if (s->srp_ctx.N != NULL)
return s->srp_ctx.N;
return s->ctx->srp_ctx.N;
}
char *SSL_get_srp_username(SSL *s)
{
if (s->srp_ctx.login != NULL)
return s->srp_ctx.login;
return s->ctx->srp_ctx.login;
}
char *SSL_get_srp_userinfo(SSL *s)
{
if (s->srp_ctx.info != NULL)
return s->srp_ctx.info;
return s->ctx->srp_ctx.info;
}
# define tls1_ctx_ctrl ssl3_ctx_ctrl
# define tls1_ctx_callback_ctrl ssl3_ctx_callback_ctrl
int SSL_CTX_set_srp_username(SSL_CTX *ctx, char *name)
{
return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_USERNAME, 0, name);
}
int SSL_CTX_set_srp_password(SSL_CTX *ctx, char *password)
{
return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_PASSWORD, 0, password);
}
int SSL_CTX_set_srp_strength(SSL_CTX *ctx, int strength)
{
return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_STRENGTH, strength,
NULL);
}
int SSL_CTX_set_srp_verify_param_callback(SSL_CTX *ctx,
int (*cb) (SSL *, void *))
{
return tls1_ctx_callback_ctrl(ctx, SSL_CTRL_SET_SRP_VERIFY_PARAM_CB,
(void (*)(void))cb);
}
int SSL_CTX_set_srp_cb_arg(SSL_CTX *ctx, void *arg)
{
return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_SRP_ARG, 0, arg);
}
int SSL_CTX_set_srp_username_callback(SSL_CTX *ctx,
int (*cb) (SSL *, int *, void *))
{
return tls1_ctx_callback_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_USERNAME_CB,
(void (*)(void))cb);
}
int SSL_CTX_set_srp_client_pwd_callback(SSL_CTX *ctx,
char *(*cb) (SSL *, void *))
{
return tls1_ctx_callback_ctrl(ctx, SSL_CTRL_SET_SRP_GIVE_CLIENT_PWD_CB,
(void (*)(void))cb);
}
#endif