int dtls1_accept(SSL *s) {
BUF_MEM *buf = NULL;
void (*cb)(const SSL *ssl, int type, int value) = NULL;
uint32_t alg_a;
int ret = -1;
int new_state, state, skip = 0;
assert(s->handshake_func == dtls1_accept);
assert(s->server);
assert(SSL_IS_DTLS(s));
ERR_clear_error();
ERR_clear_system_error();
if (s->info_callback != NULL) {
cb = s->info_callback;
} else if (s->ctx->info_callback != NULL) {
cb = s->ctx->info_callback;
}
s->in_handshake++;
for (;;) {
state = s->state;
switch (s->state) {
case SSL_ST_ACCEPT:
if (cb != NULL) {
cb(s, SSL_CB_HANDSHAKE_START, 1);
}
if (s->init_buf == NULL) {
buf = BUF_MEM_new();
if (buf == NULL || !BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
ret = -1;
goto end;
}
s->init_buf = buf;
buf = NULL;
}
s->init_num = 0;
if (!ssl_init_wbio_buffer(s, 1)) {
ret = -1;
goto end;
}
if (!ssl3_init_handshake_buffer(s)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
ret = -1;
goto end;
}
s->state = SSL3_ST_SR_CLNT_HELLO_A;
break;
case SSL3_ST_SR_CLNT_HELLO_A:
case SSL3_ST_SR_CLNT_HELLO_B:
case SSL3_ST_SR_CLNT_HELLO_C:
case SSL3_ST_SR_CLNT_HELLO_D:
s->shutdown = 0;
ret = ssl3_get_client_hello(s);
if (ret <= 0) {
goto end;
}
dtls1_stop_timer(s);
s->state = SSL3_ST_SW_SRVR_HELLO_A;
s->init_num = 0;
break;
case SSL3_ST_SW_SRVR_HELLO_A:
case SSL3_ST_SW_SRVR_HELLO_B:
dtls1_start_timer(s);
ret = ssl3_send_server_hello(s);
if (ret <= 0) {
goto end;
}
if (s->hit) {
if (s->tlsext_ticket_expected) {
s->state = SSL3_ST_SW_SESSION_TICKET_A;
} else {
s->state = SSL3_ST_SW_CHANGE_A;
}
} else {
s->state = SSL3_ST_SW_CERT_A;
}
s->init_num = 0;
break;
case SSL3_ST_SW_CERT_A:
case SSL3_ST_SW_CERT_B:
if (ssl_cipher_has_server_public_key(s->s3->tmp.new_cipher)) {
dtls1_start_timer(s);
ret = ssl3_send_server_certificate(s);
if (ret <= 0) {
goto end;
}
if (s->s3->tmp.certificate_status_expected) {
s->state = SSL3_ST_SW_CERT_STATUS_A;
} else {
s->state = SSL3_ST_SW_KEY_EXCH_A;
}
} else {
skip = 1;
s->state = SSL3_ST_SW_KEY_EXCH_A;
}
s->init_num = 0;
break;
case SSL3_ST_SW_CERT_STATUS_A:
case SSL3_ST_SW_CERT_STATUS_B:
ret = ssl3_send_certificate_status(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SW_KEY_EXCH_A;
s->init_num = 0;
break;
case SSL3_ST_SW_KEY_EXCH_A:
case SSL3_ST_SW_KEY_EXCH_B:
case SSL3_ST_SW_KEY_EXCH_C:
alg_a = s->s3->tmp.new_cipher->algorithm_auth;
/* Send a ServerKeyExchange message if:
* - The key exchange is ephemeral or anonymous
* Diffie-Hellman.
* - There is a PSK identity hint.
*
* TODO(davidben): This logic is currently duplicated
* in s3_srvr.c. Fix this. In the meantime, keep them
* in sync. */
if (ssl_cipher_requires_server_key_exchange(s->s3->tmp.new_cipher) ||
((alg_a & SSL_aPSK) && s->psk_identity_hint)) {
dtls1_start_timer(s);
ret = ssl3_send_server_key_exchange(s);
if (ret <= 0) {
goto end;
}
} else {
skip = 1;
}
s->state = SSL3_ST_SW_CERT_REQ_A;
s->init_num = 0;
break;
case SSL3_ST_SW_CERT_REQ_A:
case SSL3_ST_SW_CERT_REQ_B:
if (s->s3->tmp.cert_request) {
dtls1_start_timer(s);
ret = ssl3_send_certificate_request(s);
if (ret <= 0) {
goto end;
}
} else {
skip = 1;
}
s->state = SSL3_ST_SW_SRVR_DONE_A;
s->init_num = 0;
break;
case SSL3_ST_SW_SRVR_DONE_A:
case SSL3_ST_SW_SRVR_DONE_B:
dtls1_start_timer(s);
ret = ssl3_send_server_done(s);
if (ret <= 0) {
goto end;
}
s->s3->tmp.next_state = SSL3_ST_SR_CERT_A;
s->state = SSL3_ST_SW_FLUSH;
s->init_num = 0;
break;
case SSL3_ST_SW_FLUSH:
s->rwstate = SSL_WRITING;
if (BIO_flush(s->wbio) <= 0) {
ret = -1;
goto end;
}
s->rwstate = SSL_NOTHING;
s->state = s->s3->tmp.next_state;
break;
case SSL3_ST_SR_CERT_A:
case SSL3_ST_SR_CERT_B:
if (s->s3->tmp.cert_request) {
ret = ssl3_get_client_certificate(s);
if (ret <= 0) {
goto end;
}
}
s->init_num = 0;
s->state = SSL3_ST_SR_KEY_EXCH_A;
break;
case SSL3_ST_SR_KEY_EXCH_A:
case SSL3_ST_SR_KEY_EXCH_B:
case SSL3_ST_SR_KEY_EXCH_C:
ret = ssl3_get_client_key_exchange(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SR_CERT_VRFY_A;
s->init_num = 0;
break;
case SSL3_ST_SR_CERT_VRFY_A:
case SSL3_ST_SR_CERT_VRFY_B:
ret = ssl3_get_cert_verify(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SR_CHANGE;
s->init_num = 0;
break;
case SSL3_ST_SR_CHANGE:
ret = s->method->ssl_read_change_cipher_spec(s);
if (ret <= 0) {
goto end;
}
if (!ssl3_do_change_cipher_spec(s)) {
ret = -1;
goto end;
}
s->state = SSL3_ST_SR_FINISHED_A;
break;
case SSL3_ST_SR_FINISHED_A:
case SSL3_ST_SR_FINISHED_B:
ret =
ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, SSL3_ST_SR_FINISHED_B);
if (ret <= 0) {
goto end;
}
dtls1_stop_timer(s);
if (s->hit) {
s->state = SSL_ST_OK;
} else if (s->tlsext_ticket_expected) {
s->state = SSL3_ST_SW_SESSION_TICKET_A;
} else {
s->state = SSL3_ST_SW_CHANGE_A;
}
s->init_num = 0;
break;
case SSL3_ST_SW_SESSION_TICKET_A:
case SSL3_ST_SW_SESSION_TICKET_B:
ret = ssl3_send_new_session_ticket(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SW_CHANGE_A;
s->init_num = 0;
break;
case SSL3_ST_SW_CHANGE_A:
case SSL3_ST_SW_CHANGE_B:
s->session->cipher = s->s3->tmp.new_cipher;
if (!s->enc_method->setup_key_block(s)) {
ret = -1;
goto end;
}
ret = dtls1_send_change_cipher_spec(s, SSL3_ST_SW_CHANGE_A,
SSL3_ST_SW_CHANGE_B);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SW_FINISHED_A;
s->init_num = 0;
if (!s->enc_method->change_cipher_state(
s, SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
ret = -1;
goto end;
}
break;
case SSL3_ST_SW_FINISHED_A:
case SSL3_ST_SW_FINISHED_B:
ret =
ssl3_send_finished(s, SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B,
s->enc_method->server_finished_label,
s->enc_method->server_finished_label_len);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_SW_FLUSH;
if (s->hit) {
s->s3->tmp.next_state = SSL3_ST_SR_CHANGE;
} else {
s->s3->tmp.next_state = SSL_ST_OK;
}
s->init_num = 0;
break;
case SSL_ST_OK:
ssl3_cleanup_key_block(s);
/* remove buffering on output */
ssl_free_wbio_buffer(s);
s->init_num = 0;
s->s3->initial_handshake_complete = 1;
ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
if (cb != NULL) {
cb(s, SSL_CB_HANDSHAKE_DONE, 1);
}
ret = 1;
/* done handshaking, next message is client hello */
s->d1->handshake_read_seq = 0;
/* next message is server hello */
s->d1->handshake_write_seq = 0;
s->d1->next_handshake_write_seq = 0;
goto end;
default:
OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE);
ret = -1;
goto end;
}
if (!s->s3->tmp.reuse_message && !skip) {
if (cb != NULL && s->state != state) {
new_state = s->state;
s->state = state;
cb(s, SSL_CB_ACCEPT_LOOP, 1);
s->state = new_state;
}
}
skip = 0;
}
end:
s->in_handshake--;
BUF_MEM_free(buf);
if (cb != NULL) {
cb(s, SSL_CB_ACCEPT_EXIT, ret);
}
return ret;
}
int dtls1_connect(SSL *s) {
BUF_MEM *buf = NULL;
void (*cb)(const SSL *ssl, int type, int value) = NULL;
int ret = -1;
int new_state, state, skip = 0;
assert(s->handshake_func == dtls1_connect);
assert(!s->server);
assert(SSL_IS_DTLS(s));
ERR_clear_error();
ERR_clear_system_error();
if (s->info_callback != NULL) {
cb = s->info_callback;
} else if (s->ctx->info_callback != NULL) {
cb = s->ctx->info_callback;
}
s->in_handshake++;
for (;;) {
state = s->state;
switch (s->state) {
case SSL_ST_CONNECT:
if (cb != NULL) {
cb(s, SSL_CB_HANDSHAKE_START, 1);
}
if (s->init_buf == NULL) {
buf = BUF_MEM_new();
if (buf == NULL ||
!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
ret = -1;
goto end;
}
s->init_buf = buf;
buf = NULL;
}
if (!ssl_init_wbio_buffer(s, 0)) {
ret = -1;
goto end;
}
/* don't push the buffering BIO quite yet */
s->state = SSL3_ST_CW_CLNT_HELLO_A;
s->init_num = 0;
s->d1->send_cookie = 0;
s->hit = 0;
break;
case SSL3_ST_CW_CLNT_HELLO_A:
case SSL3_ST_CW_CLNT_HELLO_B:
s->shutdown = 0;
dtls1_start_timer(s);
ret = ssl3_send_client_hello(s);
if (ret <= 0) {
goto end;
}
if (s->d1->send_cookie) {
s->state = SSL3_ST_CW_FLUSH;
s->s3->tmp.next_state = SSL3_ST_CR_SRVR_HELLO_A;
} else {
s->state = DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
}
s->init_num = 0;
/* turn on buffering for the next lot of output */
if (s->bbio != s->wbio) {
s->wbio = BIO_push(s->bbio, s->wbio);
}
break;
case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A:
case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B:
ret = dtls1_get_hello_verify(s);
if (ret <= 0) {
goto end;
}
if (s->d1->send_cookie) {
/* start again, with a cookie */
dtls1_stop_timer(s);
s->state = SSL3_ST_CW_CLNT_HELLO_A;
} else {
s->state = SSL3_ST_CR_SRVR_HELLO_A;
}
s->init_num = 0;
break;
case SSL3_ST_CR_SRVR_HELLO_A:
case SSL3_ST_CR_SRVR_HELLO_B:
ret = ssl3_get_server_hello(s);
if (ret <= 0) {
goto end;
}
if (s->hit) {
s->state = SSL3_ST_CR_FINISHED_A;
if (s->tlsext_ticket_expected) {
/* receive renewed session ticket */
s->state = SSL3_ST_CR_SESSION_TICKET_A;
}
} else {
s->state = SSL3_ST_CR_CERT_A;
}
s->init_num = 0;
break;
case SSL3_ST_CR_CERT_A:
case SSL3_ST_CR_CERT_B:
if (ssl_cipher_has_server_public_key(s->s3->tmp.new_cipher)) {
ret = ssl3_get_server_certificate(s);
if (ret <= 0) {
goto end;
}
if (s->s3->tmp.certificate_status_expected) {
s->state = SSL3_ST_CR_CERT_STATUS_A;
} else {
s->state = SSL3_ST_VERIFY_SERVER_CERT;
}
} else {
skip = 1;
s->state = SSL3_ST_CR_KEY_EXCH_A;
}
s->init_num = 0;
break;
case SSL3_ST_VERIFY_SERVER_CERT:
ret = ssl3_verify_server_cert(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CR_KEY_EXCH_A;
s->init_num = 0;
break;
case SSL3_ST_CR_KEY_EXCH_A:
case SSL3_ST_CR_KEY_EXCH_B:
ret = ssl3_get_server_key_exchange(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CR_CERT_REQ_A;
s->init_num = 0;
break;
case SSL3_ST_CR_CERT_REQ_A:
case SSL3_ST_CR_CERT_REQ_B:
ret = ssl3_get_certificate_request(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CR_SRVR_DONE_A;
s->init_num = 0;
break;
case SSL3_ST_CR_SRVR_DONE_A:
case SSL3_ST_CR_SRVR_DONE_B:
ret = ssl3_get_server_done(s);
if (ret <= 0) {
goto end;
}
dtls1_stop_timer(s);
if (s->s3->tmp.cert_req) {
s->s3->tmp.next_state = SSL3_ST_CW_CERT_A;
} else {
s->s3->tmp.next_state = SSL3_ST_CW_KEY_EXCH_A;
}
s->init_num = 0;
s->state = s->s3->tmp.next_state;
break;
case SSL3_ST_CW_CERT_A:
case SSL3_ST_CW_CERT_B:
case SSL3_ST_CW_CERT_C:
case SSL3_ST_CW_CERT_D:
dtls1_start_timer(s);
ret = ssl3_send_client_certificate(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CW_KEY_EXCH_A;
s->init_num = 0;
break;
case SSL3_ST_CW_KEY_EXCH_A:
case SSL3_ST_CW_KEY_EXCH_B:
dtls1_start_timer(s);
ret = ssl3_send_client_key_exchange(s);
if (ret <= 0) {
goto end;
}
/* For TLS, cert_req is set to 2, so a cert chain
* of nothing is sent, but no verify packet is sent */
if (s->s3->tmp.cert_req == 1) {
s->state = SSL3_ST_CW_CERT_VRFY_A;
} else {
s->state = SSL3_ST_CW_CHANGE_A;
s->s3->change_cipher_spec = 0;
}
s->init_num = 0;
break;
case SSL3_ST_CW_CERT_VRFY_A:
case SSL3_ST_CW_CERT_VRFY_B:
case SSL3_ST_CW_CERT_VRFY_C:
dtls1_start_timer(s);
ret = ssl3_send_cert_verify(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CW_CHANGE_A;
s->init_num = 0;
s->s3->change_cipher_spec = 0;
break;
case SSL3_ST_CW_CHANGE_A:
case SSL3_ST_CW_CHANGE_B:
if (!s->hit) {
dtls1_start_timer(s);
}
ret = dtls1_send_change_cipher_spec(s, SSL3_ST_CW_CHANGE_A,
SSL3_ST_CW_CHANGE_B);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CW_FINISHED_A;
s->init_num = 0;
s->session->cipher = s->s3->tmp.new_cipher;
if (!s->enc_method->setup_key_block(s) ||
!s->enc_method->change_cipher_state(
s, SSL3_CHANGE_CIPHER_CLIENT_WRITE)) {
ret = -1;
goto end;
}
break;
case SSL3_ST_CW_FINISHED_A:
case SSL3_ST_CW_FINISHED_B:
if (!s->hit) {
dtls1_start_timer(s);
}
ret =
ssl3_send_finished(s, SSL3_ST_CW_FINISHED_A, SSL3_ST_CW_FINISHED_B,
s->enc_method->client_finished_label,
s->enc_method->client_finished_label_len);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CW_FLUSH;
if (s->hit) {
s->s3->tmp.next_state = SSL_ST_OK;
} else {
/* Allow NewSessionTicket if ticket expected */
if (s->tlsext_ticket_expected) {
s->s3->tmp.next_state = SSL3_ST_CR_SESSION_TICKET_A;
} else {
s->s3->tmp.next_state = SSL3_ST_CR_FINISHED_A;
}
}
s->init_num = 0;
break;
case SSL3_ST_CR_SESSION_TICKET_A:
case SSL3_ST_CR_SESSION_TICKET_B:
ret = ssl3_get_new_session_ticket(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_CR_FINISHED_A;
s->init_num = 0;
break;
case SSL3_ST_CR_CERT_STATUS_A:
case SSL3_ST_CR_CERT_STATUS_B:
ret = ssl3_get_cert_status(s);
if (ret <= 0) {
goto end;
}
s->state = SSL3_ST_VERIFY_SERVER_CERT;
s->init_num = 0;
break;
case SSL3_ST_CR_FINISHED_A:
case SSL3_ST_CR_FINISHED_B:
s->d1->change_cipher_spec_ok = 1;
ret =
ssl3_get_finished(s, SSL3_ST_CR_FINISHED_A, SSL3_ST_CR_FINISHED_B);
if (ret <= 0) {
goto end;
}
dtls1_stop_timer(s);
if (s->hit) {
s->state = SSL3_ST_CW_CHANGE_A;
} else {
s->state = SSL_ST_OK;
}
s->init_num = 0;
break;
case SSL3_ST_CW_FLUSH:
s->rwstate = SSL_WRITING;
if (BIO_flush(s->wbio) <= 0) {
ret = -1;
goto end;
}
s->rwstate = SSL_NOTHING;
s->state = s->s3->tmp.next_state;
break;
case SSL_ST_OK:
/* clean a few things up */
ssl3_cleanup_key_block(s);
/* Remove write buffering now. */
ssl_free_wbio_buffer(s);
s->init_num = 0;
s->s3->initial_handshake_complete = 1;
ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
ret = 1;
if (cb != NULL) {
cb(s, SSL_CB_HANDSHAKE_DONE, 1);
}
/* done with handshaking */
s->d1->handshake_read_seq = 0;
s->d1->next_handshake_write_seq = 0;
goto end;
default:
OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE);
ret = -1;
goto end;
}
/* did we do anything? */
if (!s->s3->tmp.reuse_message && !skip) {
if ((cb != NULL) && (s->state != state)) {
new_state = s->state;
s->state = state;
cb(s, SSL_CB_CONNECT_LOOP, 1);
s->state = new_state;
}
}
skip = 0;
}
end:
s->in_handshake--;
BUF_MEM_free(buf);
if (cb != NULL) {
cb(s, SSL_CB_CONNECT_EXIT, ret);
}
return ret;
}
