diff options
Diffstat (limited to 'demos/tunala/sm.c')
-rw-r--r-- | demos/tunala/sm.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/demos/tunala/sm.c b/demos/tunala/sm.c new file mode 100644 index 0000000..25359e6 --- /dev/null +++ b/demos/tunala/sm.c @@ -0,0 +1,151 @@ +#include "tunala.h" + +#ifndef NO_TUNALA + +void state_machine_init(state_machine_t *machine) +{ + machine->ssl = NULL; + machine->bio_intossl = machine->bio_fromssl = NULL; + buffer_init(&machine->clean_in); + buffer_init(&machine->clean_out); + buffer_init(&machine->dirty_in); + buffer_init(&machine->dirty_out); +} + +void state_machine_close(state_machine_t *machine) +{ + if(machine->ssl) + SSL_free(machine->ssl); +/* SSL_free seems to decrement the reference counts already so doing this goes + * kaboom. */ +#if 0 + if(machine->bio_intossl) + BIO_free(machine->bio_intossl); + if(machine->bio_fromssl) + BIO_free(machine->bio_fromssl); +#endif + buffer_close(&machine->clean_in); + buffer_close(&machine->clean_out); + buffer_close(&machine->dirty_in); + buffer_close(&machine->dirty_out); + state_machine_init(machine); +} + +buffer_t *state_machine_get_buffer(state_machine_t *machine, sm_buffer_t type) +{ + switch(type) { + case SM_CLEAN_IN: + return &machine->clean_in; + case SM_CLEAN_OUT: + return &machine->clean_out; + case SM_DIRTY_IN: + return &machine->dirty_in; + case SM_DIRTY_OUT: + return &machine->dirty_out; + default: + break; + } + /* Should never get here */ + abort(); + return NULL; +} + +SSL *state_machine_get_SSL(state_machine_t *machine) +{ + return machine->ssl; +} + +int state_machine_set_SSL(state_machine_t *machine, SSL *ssl, int is_server) +{ + if(machine->ssl) + /* Shouldn't ever be set twice */ + abort(); + machine->ssl = ssl; + /* Create the BIOs to handle the dirty side of the SSL */ + if((machine->bio_intossl = BIO_new(BIO_s_mem())) == NULL) + abort(); + if((machine->bio_fromssl = BIO_new(BIO_s_mem())) == NULL) + abort(); + /* Hook up the BIOs on the dirty side of the SSL */ + SSL_set_bio(machine->ssl, machine->bio_intossl, machine->bio_fromssl); + if(is_server) + SSL_set_accept_state(machine->ssl); + else + SSL_set_connect_state(machine->ssl); + /* If we're the first one to generate traffic - do it now otherwise we + * go into the next select empty-handed and our peer will not send data + * but will similarly wait for us. */ + return state_machine_churn(machine); +} + +/* Performs the data-IO loop and returns zero if the machine should close */ +int state_machine_churn(state_machine_t *machine) +{ + unsigned int loop; + if(machine->ssl == NULL) { + if(buffer_empty(&machine->clean_out)) + /* Time to close this state-machine altogether */ + return 0; + else + /* Still buffered data on the clean side to go out */ + return 1; + } + /* Do this loop twice to cover any dependencies about which precise + * order of reads and writes is required. */ + for(loop = 0; loop < 2; loop++) { + buffer_to_SSL(&machine->clean_in, machine->ssl); + buffer_to_BIO(&machine->dirty_in, machine->bio_intossl); + buffer_from_SSL(&machine->clean_out, machine->ssl); + buffer_from_BIO(&machine->dirty_out, machine->bio_fromssl); + } + /* We close on the SSL side if the info callback noticed some problems + * or an SSL shutdown was underway and shutdown traffic had all been + * sent. */ + if(SSL_get_app_data(machine->ssl) || (SSL_get_shutdown(machine->ssl) && + buffer_empty(&machine->dirty_out))) { + /* Great, we can seal off the dirty side completely */ + if(!state_machine_close_dirty(machine)) + return 0; + } + /* Either the SSL is alive and well, or the closing process still has + * outgoing data waiting to be sent */ + return 1; +} + +/* Called when the clean side of the SSL has lost its connection */ +int state_machine_close_clean(state_machine_t *machine) +{ + /* Well, first thing to do is null out the clean-side buffers - they're + * no use any more. */ + buffer_close(&machine->clean_in); + buffer_close(&machine->clean_out); + /* And start an SSL shutdown */ + if(machine->ssl) + SSL_shutdown(machine->ssl); + /* This is an "event", so flush the SSL of any generated traffic */ + state_machine_churn(machine); + if(buffer_empty(&machine->dirty_in) && + buffer_empty(&machine->dirty_out)) + return 0; + return 1; +} + +/* Called when the dirty side of the SSL has lost its connection. This is pretty + * terminal as all that can be left to do is send any buffered output on the + * clean side - after that, we're done. */ +int state_machine_close_dirty(state_machine_t *machine) +{ + buffer_close(&machine->dirty_in); + buffer_close(&machine->dirty_out); + buffer_close(&machine->clean_in); + if(machine->ssl) + SSL_free(machine->ssl); + machine->ssl = NULL; + machine->bio_intossl = machine->bio_fromssl = NULL; + if(buffer_empty(&machine->clean_out)) + return 0; + return 1; +} + +#endif /* !defined(NO_TUNALA) */ + |