Commit 25c6c10c authored by Matt Caswell's avatar Matt Caswell
Browse files

Split out SRP from tls_process_key_exchange() 



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

Reviewed-by: default avatarRichard Levitte <levitte@openssl.org>
parent 7dc1c647

ssl/statem/statem_clnt.c

+51 −36
Original line number Diff line number Diff line
@@ -1344,6 +1344,55 @@ static int tls_process_ske_psk_preamble(SSL *s, PACKET *pkt, int *al) 
#endif

}



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

{

#ifndef OPENSSL_NO_SRP

    PACKET prime, generator, salt, server_pub;



    if (!PACKET_get_length_prefixed_2(pkt, &prime)

        || !PACKET_get_length_prefixed_2(pkt, &generator)

        || !PACKET_get_length_prefixed_1(pkt, &salt)

        || !PACKET_get_length_prefixed_2(pkt, &server_pub)) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_LENGTH_MISMATCH);

        return 0;

    }



    if ((s->srp_ctx.N =

         BN_bin2bn(PACKET_data(&prime),

                   PACKET_remaining(&prime), NULL)) == NULL

        || (s->srp_ctx.g =

            BN_bin2bn(PACKET_data(&generator),

                      PACKET_remaining(&generator), NULL)) == NULL

        || (s->srp_ctx.s =

            BN_bin2bn(PACKET_data(&salt),

                      PACKET_remaining(&salt), NULL)) == NULL

        || (s->srp_ctx.B =

            BN_bin2bn(PACKET_data(&server_pub),

                      PACKET_remaining(&server_pub), NULL)) == NULL) {

        *al = SSL_AD_INTERNAL_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_BN_LIB);

        return 0;

    }



    if (!srp_verify_server_param(s, al)) {

        *al = SSL_AD_DECODE_ERROR;

        SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_BAD_SRP_PARAMETERS);

        return 0;

    }



    /* We must check if there is a certificate */

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

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



    return 1;

#else

    SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_INTERNAL_ERROR);

    *al = SSL_AD_INTERNAL_ERROR;

    return 0;

#endif

}



MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt)

{

    EVP_MD_CTX *md_ctx;
@@ -1377,44 +1426,10 @@ MSG_PROCESS_RETURN tls_process_key_exchange(SSL *s, PACKET *pkt) 


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

    if (alg_k & (SSL_kPSK | SSL_kRSAPSK)) {

    }

#ifndef OPENSSL_NO_SRP

    else if (alg_k & SSL_kSRP) {

        PACKET prime, generator, salt, server_pub;

        if (!PACKET_get_length_prefixed_2(pkt, &prime)

            || !PACKET_get_length_prefixed_2(pkt, &generator)

            || !PACKET_get_length_prefixed_1(pkt, &salt)

            || !PACKET_get_length_prefixed_2(pkt, &server_pub)) {

            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_LENGTH_MISMATCH);

            goto f_err;

        }



        if ((s->srp_ctx.N =

             BN_bin2bn(PACKET_data(&prime),

                       PACKET_remaining(&prime), NULL)) == NULL

            || (s->srp_ctx.g =

                BN_bin2bn(PACKET_data(&generator),

                          PACKET_remaining(&generator), NULL)) == NULL

            || (s->srp_ctx.s =

                BN_bin2bn(PACKET_data(&salt),

                          PACKET_remaining(&salt), NULL)) == NULL

            || (s->srp_ctx.B =

                BN_bin2bn(PACKET_data(&server_pub),

                          PACKET_remaining(&server_pub), NULL)) == NULL) {

            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, ERR_R_BN_LIB);

    } else if (alg_k & SSL_kSRP) {

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

            goto err;

    }



        if (!srp_verify_server_param(s, &al)) {

            SSLerr(SSL_F_TLS_PROCESS_KEY_EXCHANGE, SSL_R_BAD_SRP_PARAMETERS);

            goto f_err;

        }



/* We must check if there is a certificate */

        if (alg_a & (SSL_aRSA|SSL_aDSS))

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

    }

#endif                          /* !OPENSSL_NO_SRP */

#ifndef OPENSSL_NO_DH

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

        PACKET prime, generator, pub_key;