Commit 4a01c59f authored by Matt Caswell's avatar Matt Caswell
Browse files

Harmonise setting the header and closing construction 



Ensure all message types work the same way including CCS so that the state
machine doesn't need to know about special cases. Put all the special logic
into ssl_set_handshake_header() and ssl_close_construct_packet().

Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
parent 5923ad4b

ssl/s3_lib.c

+4 −0
Original line number Diff line number Diff line
@@ -2779,6 +2779,10 @@ const SSL_CIPHER *ssl3_get_cipher(unsigned int u) 


int ssl3_set_handshake_header(SSL *s, WPACKET *pkt, int htype)

{

    /* No header in the event of a CCS */

    if (htype == SSL3_MT_CHANGE_CIPHER_SPEC)

        return 1;



    /* Set the content type and 3 bytes for the message len */

    if (!WPACKET_put_bytes_u8(pkt, htype)

            || !WPACKET_start_sub_packet_u24(pkt))

ssl/ssl_locl.h

+5 −5
Original line number Diff line number Diff line
@@ -1586,7 +1586,7 @@ typedef struct ssl3_enc_method { 
    /* Set the handshake header */

    int (*set_handshake_header) (SSL *s, WPACKET *pkt, int type);

    /* Close construction of the handshake message */

    int (*close_construct_packet) (SSL *s, WPACKET *pkt);

    int (*close_construct_packet) (SSL *s, WPACKET *pkt, int htype);

    /* Write out handshake message */

    int (*do_write) (SSL *s);

} SSL3_ENC_METHOD;
@@ -1596,8 +1596,8 @@ typedef struct ssl3_enc_method { 
        (((unsigned char *)s->init_buf->data) + s->method->ssl3_enc->hhlen)

# define ssl_set_handshake_header(s, pkt, htype) \

        s->method->ssl3_enc->set_handshake_header((s), (pkt), (htype))

# define ssl_close_construct_packet(s, pkt) \

        s->method->ssl3_enc->close_construct_packet((s), (pkt))

# define ssl_close_construct_packet(s, pkt, htype) \

        s->method->ssl3_enc->close_construct_packet((s), (pkt), (htype))

# define ssl_do_write(s)  s->method->ssl3_enc->do_write(s)



/* Values for enc_flags */
@@ -1901,9 +1901,9 @@ __owur int ssl3_do_change_cipher_spec(SSL *ssl); 
__owur long ssl3_default_timeout(void);



__owur int ssl3_set_handshake_header(SSL *s, WPACKET *pkt, int htype);

__owur int tls_close_construct_packet(SSL *s, WPACKET *pkt);

__owur int tls_close_construct_packet(SSL *s, WPACKET *pkt, int htype);

__owur int dtls1_set_handshake_header(SSL *s, WPACKET *pkt, int htype);

__owur int dtls1_close_construct_packet(SSL *s, WPACKET *pkt);

__owur int dtls1_close_construct_packet(SSL *s, WPACKET *pkt, int htype);

__owur int ssl3_handshake_write(SSL *s);



__owur int ssl_allow_compression(SSL *s);

ssl/statem/statem_clnt.c

+52 −52
Original line number Diff line number Diff line
@@ -516,18 +516,19 @@ int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt) 
    int (*confunc) (SSL *s, WPACKET *pkt) = NULL;

    int ret = 1, mt;



    if (st->hand_state == TLS_ST_CW_CHANGE) {

        /* Special case becase it is a different content type */

        if (SSL_IS_DTLS(s))

            return dtls_construct_change_cipher_spec(s, pkt);



        return tls_construct_change_cipher_spec(s, pkt);

    } else {

    switch (st->hand_state) {

    default:

        /* Shouldn't happen */

        return 0;



    case TLS_ST_CW_CHANGE:

        if (SSL_IS_DTLS(s))

            confunc = dtls_construct_change_cipher_spec;

        else

            confunc = tls_construct_change_cipher_spec;

        mt = SSL3_MT_CHANGE_CIPHER_SPEC;

        break;



    case TLS_ST_CW_CLNT_HELLO:

        confunc = tls_construct_client_hello;

        mt = SSL3_MT_CLIENT_HELLO;
@@ -574,12 +575,11 @@ int ossl_statem_client_construct_message(SSL *s, WPACKET *pkt) 
    else

        ret = confunc(s, pkt);



        if (!ret || !ssl_close_construct_packet(s, pkt)) {

    if (!ret || !ssl_close_construct_packet(s, pkt, mt)) {

        SSLerr(SSL_F_OSSL_STATEM_CLIENT_CONSTRUCT_MESSAGE,

               ERR_R_INTERNAL_ERROR);

        return 0;

    }

    }

    return 1;

}

ssl/statem/statem_dtls.c

+30 −42
Original line number Diff line number Diff line
@@ -874,41 +874,16 @@ static int dtls_get_reassembled_message(SSL *s, long *len) 
 */

int dtls_construct_change_cipher_spec(SSL *s, WPACKET *pkt)

{

    if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) {

        SSLerr(SSL_F_DTLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);

        goto err;

    }



    s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;

    s->init_num = DTLS1_CCS_HEADER_LENGTH;



    if (s->version == DTLS1_BAD_VER) {

        s->d1->next_handshake_write_seq++;



        if (!WPACKET_put_bytes_u16(pkt, s->d1->handshake_write_seq)) {

            SSLerr(SSL_F_DTLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);

            goto err;

        }



        s->init_num += 2;

            ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);

        }



    s->init_off = 0;



    dtls1_set_message_header_int(s, SSL3_MT_CCS, 0,

                                 s->d1->handshake_write_seq, 0, 0);



    /* buffer the message to handle re-xmits */

    if (!dtls1_buffer_message(s, 1)) {

        SSLerr(SSL_F_DTLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);

        goto err    ;

    }



    return 1;



 err:

    ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);

    return 0;

}



#ifndef OPENSSL_NO_SCTP
@@ -1206,35 +1181,48 @@ int dtls1_set_handshake_header(SSL *s, WPACKET *pkt, int htype) 
{

    unsigned char *header;



    if (htype == SSL3_MT_CHANGE_CIPHER_SPEC) {

        s->d1->handshake_write_seq = s->d1->next_handshake_write_seq;

        dtls1_set_message_header_int(s, SSL3_MT_CCS, 0,

                                     s->d1->handshake_write_seq, 0, 0);

        if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS))

            return 0;

    } else {

        dtls1_set_message_header(s, htype, 0, 0, 0);



        /*

     * We allocate space at the start for the message header. This gets filled

     * in later

         * We allocate space at the start for the message header. This gets

         * filled in later

         */

        if (!WPACKET_allocate_bytes(pkt, DTLS1_HM_HEADER_LENGTH, &header)

                || !WPACKET_start_sub_packet(pkt))

            return 0;

    }



    return 1;

}



int dtls1_close_construct_packet(SSL *s, WPACKET *pkt)

int dtls1_close_construct_packet(SSL *s, WPACKET *pkt, int htype)

{

    size_t msglen;



    if (!WPACKET_close(pkt)

    if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt))

            || !WPACKET_get_length(pkt, &msglen)

            || msglen > INT_MAX)

        return 0;



    if (htype != SSL3_MT_CHANGE_CIPHER_SPEC) {

        s->d1->w_msg_hdr.msg_len = msglen - DTLS1_HM_HEADER_LENGTH;

        s->d1->w_msg_hdr.frag_len = msglen - DTLS1_HM_HEADER_LENGTH;

    }

    s->init_num = (int)msglen;

    s->init_off = 0;



    if (htype != DTLS1_MT_HELLO_VERIFY_REQUEST) {

        /* Buffer the message to handle re-xmits */

    if (!dtls1_buffer_message(s, 0))

        if (!dtls1_buffer_message(s, htype == SSL3_MT_CHANGE_CIPHER_SPEC

                                     ? 1 : 0))

            return 0;

    }



    return 1;

}

ssl/statem/statem_lib.c

+2 −5
Original line number Diff line number Diff line
@@ -57,11 +57,11 @@ int ssl3_do_write(SSL *s, int type) 
    return (0);

}



int tls_close_construct_packet(SSL *s, WPACKET *pkt)

int tls_close_construct_packet(SSL *s, WPACKET *pkt, int htype)

{

    size_t msglen;



    if (!WPACKET_close(pkt)

    if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt))

            || !WPACKET_get_length(pkt, &msglen)

            || msglen > INT_MAX)

        return 0;
@@ -260,9 +260,6 @@ int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt) 
        return 0;

    }



    s->init_num = 1;

    s->init_off = 0;



    return 1;

}