From a8c1c7040aabdb78f9bec21ba16be8f262de1444 Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Fri, 8 Jul 2016 09:42:07 +0100 Subject: [PATCH] Split out DHE CKE construction into a separate function Continuing previous commit to break up the tls_construct_client_key_exchange() function. This splits out the DHE code. Reviewed-by: Richard Levitte --- ssl/statem/statem_clnt.c | 74 ++++++++++++++++++++++------------------ 1 file changed, 41 insertions(+), 33 deletions(-) diff --git a/ssl/statem/statem_clnt.c b/ssl/statem/statem_clnt.c index c2ecd68e0a..b297ca1140 100644 --- a/ssl/statem/statem_clnt.c +++ b/ssl/statem/statem_clnt.c @@ -2187,6 +2187,45 @@ static int tls_construct_cke_rsa(SSL *s, unsigned char **p, int *len, int *al) #endif } +static int tls_construct_cke_dhe(SSL *s, unsigned char **p, int *len, int *al) +{ +#ifndef OPENSSL_NO_DH + DH *dh_clnt = NULL; + const BIGNUM *pub_key; + EVP_PKEY *ckey = NULL, *skey = NULL; + + skey = s->s3->peer_tmp; + if (skey == NULL) { + SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, + ERR_R_INTERNAL_ERROR); + return 0; + } + ckey = ssl_generate_pkey(skey, NID_undef); + dh_clnt = EVP_PKEY_get0_DH(ckey); + + if (dh_clnt == NULL || ssl_derive(s, ckey, skey) == 0) { + SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, + ERR_R_INTERNAL_ERROR); + EVP_PKEY_free(ckey); + return 0; + } + + /* send off the data */ + DH_get0_key(dh_clnt, &pub_key, NULL); + *len = BN_num_bytes(pub_key); + s2n(*len, *p); + BN_bn2bin(pub_key, *p); + *len += 2; + EVP_PKEY_free(ckey); + + return 1; +#else + SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR); + *al = SSL_AD_INTERNAL_ERROR; + return 0; +#endif +} + int tls_construct_client_key_exchange(SSL *s) { unsigned char *p; @@ -2210,41 +2249,10 @@ int tls_construct_client_key_exchange(SSL *s) } else if (alg_k & (SSL_kRSA | SSL_kRSAPSK)) { if (!tls_construct_cke_rsa(s, &p, &n, &al)) goto err; - } -#ifndef OPENSSL_NO_DH - else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) { - DH *dh_clnt = NULL; - const BIGNUM *pub_key; - EVP_PKEY *ckey = NULL, *skey = NULL; - - skey = s->s3->peer_tmp; - if (skey == NULL) { - SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, - ERR_R_INTERNAL_ERROR); - goto err; - } - ckey = ssl_generate_pkey(skey, NID_undef); - dh_clnt = EVP_PKEY_get0_DH(ckey); - - if (dh_clnt == NULL || ssl_derive(s, ckey, skey) == 0) { - SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_KEY_EXCHANGE, - ERR_R_INTERNAL_ERROR); - EVP_PKEY_free(ckey); + } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) { + if (!tls_construct_cke_dhe(s, &p, &n, &al)) goto err; - } - - - /* send off the data */ - DH_get0_key(dh_clnt, &pub_key, NULL); - n = BN_num_bytes(pub_key); - s2n(n, p); - BN_bn2bin(pub_key, p); - n += 2; - EVP_PKEY_free(ckey); - ckey = NULL; } -#endif - #ifndef OPENSSL_NO_EC else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) { unsigned char *encodedPoint = NULL; -- 2.25.1