Commit ff74aeb1 authored by Matt Caswell's avatar Matt Caswell
Browse files

Split out ECDHE from tls_process_key_exchange() 



Continuing from the previous commit. Refactor tls_process_key_exchange() to
split out into a separate function the ECDHE aspects.

Reviewed-by: default avatarRichard Levitte <levitte@openssl.org>
parent e01a610d

ssl/statem/statem_clnt.c

+86 −76
Original line number Diff line number Diff line
@@ -1489,48 +1489,9 @@ static int tls_process_ske_dhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey, int *al) 
#endif

}



MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)

static int tls_process_ske_ecdhe(SSL *s, PACKET *pkt, EVP_PKEY **pkey, int *al)

{

    EVP_MD_CTX *md_ctx;

    int al = -1;

    long alg_k, alg_a;

    EVP_PKEY *pkey = NULL;

    PACKET save_param_start, signature;



    md_ctx = EVP_MD_CTX_new();

    if (md_ctx == NULL) {

        al = SSL_AD_INTERNAL_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_MALLOC_FAILURE);

        goto f_err;

    }



    alg_k = s->s3->tmp.new_cipher->algorithm_mkey;



    save_param_start = *pkt;



#if !defined(OPENSSL_NO_EC) || !defined(OPENSSL_NO_DH)

    EVP_PKEY_free(s->s3->peer_tmp);

    s->s3->peer_tmp = NULL;

#endif



    alg_a = s->s3->tmp.new_cipher->algorithm_auth;



    if (alg_k & SSL_PSK) {

        if (!tls_process_ske_psk_preamble(s, pkt, &al))

            goto err;

    }



    /* Nothing else to do for plain PSK or RSAPSK */

    if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {

    } else if (alg_k & SSL_kSRP) {

        if (!tls_process_ske_srp(s, pkt, &pkey, &al))

            goto err;

    } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {

        if (!tls_process_ske_dhe(s, pkt, &pkey, &al))

            goto err;

    }

#ifndef OPENSSL_NO_EC

    else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {

    PACKET encoded_pt;

    const unsigned char *ecparams;

    int curve_nid;
@@ -1542,24 +1503,26 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt) 
     * ECParameters in this case is just three bytes.

     */

    if (!PACKET_get_bytes(pkt, &ecparams, 3)) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_LENGTH_TOO_SHORT);

            goto f_err;

        return 0;

    }

    /*

     * Check curve is one of our preferences, if not server has sent an

     * invalid curve. ECParameters is 3 bytes.

     */

    if (!tls1_check_curve(s, ecparams, 3)) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_WRONG_CURVE);

            goto f_err;

        return 0;

    }



    curve_nid = tls1_ec_curve_id2nid(*(ecparams + 2));

    if (curve_nid  == 0) {

            al = SSL_AD_INTERNAL_ERROR;

        *al = SSL_AD_INTERNAL_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE,

               SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);

            goto f_err;

        return 0;

    }



    /* Set up EVP_PKEY with named curve as parameters */
@@ -1568,24 +1531,26 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt) 
        || EVP_PKEY_paramgen_init(pctx) <= 0

        || EVP_PKEY_CTX_set_ec_paramgen_curve_nid(pctx, curve_nid) <= 0

        || EVP_PKEY_paramgen(pctx, &s->s3->peer_tmp) <= 0) {

            al = SSL_AD_INTERNAL_ERROR;

        *al = SSL_AD_INTERNAL_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_EVP_LIB);

        EVP_PKEY_CTX_free(pctx);

            goto f_err;

        return 0;

    }

    EVP_PKEY_CTX_free(pctx);

    pctx = NULL;



    if (!PACKET_get_length_prefixed_1(pkt, &encoded_pt)) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_LENGTH_MISMATCH);

            goto f_err;

        return 0;

    }



    if (EC_KEY_oct2key(EVP_PKEY_get0_EC_KEY(s->s3->peer_tmp),

                       PACKET_data(&encoded_pt),

                       PACKET_remaining(&encoded_pt), NULL) == 0) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_BAD_ECPOINT);

            goto f_err;

        return 0;

    }



    /*
@@ -1593,22 +1558,67 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt) 
     * ECParameters in the server key exchange message. We do support RSA

     * and ECDSA.

     */

        if (0) ;

# ifndef OPENSSL_NO_RSA

        else if (alg_a & SSL_aRSA)

            pkey = X509_get0_pubkey(s->session->peer);

    if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aECDSA)

        *pkey = X509_get0_pubkey(s->session->peer);

    else if (s->s3->tmp.new_cipher->algorithm_auth & SSL_aRSA)

        *pkey = X509_get0_pubkey(s->session->peer);

    /* else anonymous ECDH, so no certificate or pkey. */



    return 1;

#else

    SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);

    *al = SSL_AD_INTERNAL_ERROR;

    return 0;

#endif

# ifndef OPENSSL_NO_EC

        else if (alg_a & SSL_aECDSA)

            pkey = X509_get0_pubkey(s->session->peer);

}



MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)

{

    EVP_MD_CTX *md_ctx;

    int al = -1;

    long alg_k, alg_a;

    EVP_PKEY *pkey = NULL;

    PACKET save_param_start, signature;



    md_ctx = EVP_MD_CTX_new();

    if (md_ctx == NULL) {

        al = SSL_AD_INTERNAL_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_MALLOC_FAILURE);

        goto f_err;

    }



    alg_k = s->s3->tmp.new_cipher->algorithm_mkey;



    save_param_start = *pkt;



#if !defined(OPENSSL_NO_EC) || !defined(OPENSSL_NO_DH)

    EVP_PKEY_free(s->s3->peer_tmp);

    s->s3->peer_tmp = NULL;

#endif

        /* else anonymous ECDH, so no certificate or pkey. */



    alg_a = s->s3->tmp.new_cipher->algorithm_auth;



    if (alg_k & SSL_PSK) {

        if (!tls_process_ske_psk_preamble(s, pkt, &al))

            goto err;

    }



    /* Nothing else to do for plain PSK or RSAPSK */

    if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {

    } else if (alg_k & SSL_kSRP) {

        if (!tls_process_ske_srp(s, pkt, &pkey, &al))

            goto err;

    } else if (alg_k & (SSL_kDHE | SSL_kDHEPSK)) {

        if (!tls_process_ske_dhe(s, pkt, &pkey, &al))

            goto err;

    } else if (alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) {

        if (!tls_process_ske_ecdhe(s, pkt, &pkey, &al))

            goto err;

    } else if (alg_k) {

        al = SSL_AD_UNEXPECTED_MESSAGE;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_UNEXPECTED_MESSAGE);

        goto f_err;

    }

#endif                          /* !OPENSSL_NO_EC */



    /* if it was signed, check the signature */

    if (pkey != NULL) {