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|
/* Copyright 2001,2002 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */
#include "or.h"
extern or_options_t options; /* command-line and config-file options */
static int or_handshake_op_send_keys(connection_t *conn);
static int or_handshake_op_finished_sending_keys(connection_t *conn);
static int or_handshake_client_process_auth(connection_t *conn);
static int or_handshake_client_send_auth(connection_t *conn);
static int or_handshake_server_process_auth(connection_t *conn);
static int or_handshake_server_process_nonce(connection_t *conn);
static void connection_or_set_open(connection_t *conn);
static void conn_or_init_crypto(connection_t *conn);
/*
*
* these two functions are the main ways 'in' to connection_or
*
*/
int connection_or_process_inbuf(connection_t *conn) {
assert(conn && conn->type == CONN_TYPE_OR);
if(conn->inbuf_reached_eof) {
/* eof reached, kill it. */
log_fn(LOG_DEBUG,"conn reached eof. Closing.");
return -1;
}
// log(LOG_DEBUG,"connection_or_process_inbuf(): state %d.",conn->state);
switch(conn->state) {
case OR_CONN_STATE_CLIENT_AUTH_WAIT:
return or_handshake_client_process_auth(conn);
case OR_CONN_STATE_SERVER_AUTH_WAIT:
return or_handshake_server_process_auth(conn);
case OR_CONN_STATE_SERVER_NONCE_WAIT:
return or_handshake_server_process_nonce(conn);
case OR_CONN_STATE_OPEN:
return connection_process_cell_from_inbuf(conn);
default:
log_fn(LOG_DEBUG,"called in state where I'm writing. Ignoring buf for now.");
}
return 0;
}
int connection_or_finished_flushing(connection_t *conn) {
int e, len=sizeof(e);
assert(conn && conn->type == CONN_TYPE_OR);
switch(conn->state) {
case OR_CONN_STATE_OP_SENDING_KEYS:
return or_handshake_op_finished_sending_keys(conn);
case OR_CONN_STATE_CLIENT_CONNECTING:
if (getsockopt(conn->s, SOL_SOCKET, SO_ERROR, &e, &len) < 0) { /* not yet */
if(errno != EINPROGRESS){
/* yuck. kill it. */
log_fn(LOG_DEBUG,"in-progress connect failed. Removing.");
return -1;
} else {
return 0; /* no change, see if next time is better */
}
}
/* the connect has finished. */
log_fn(LOG_DEBUG,"OR connection to router %s:%u established.",
conn->address,conn->port);
if(options.OnionRouter)
return or_handshake_client_send_auth(conn);
else
return or_handshake_op_send_keys(conn);
case OR_CONN_STATE_CLIENT_SENDING_AUTH:
log_fn(LOG_DEBUG,"client finished sending auth.");
conn->state = OR_CONN_STATE_CLIENT_AUTH_WAIT;
connection_watch_events(conn, POLLIN);
return 0;
case OR_CONN_STATE_CLIENT_SENDING_NONCE:
log_fn(LOG_DEBUG,"client finished sending nonce.");
conn_or_init_crypto(conn);
connection_or_set_open(conn);
return connection_process_inbuf(conn); /* in case there's anything waiting on it */
case OR_CONN_STATE_SERVER_SENDING_AUTH:
log_fn(LOG_DEBUG,"server finished sending auth.");
conn->state = OR_CONN_STATE_SERVER_NONCE_WAIT;
connection_watch_events(conn, POLLIN);
return 0;
case OR_CONN_STATE_OPEN:
/* FIXME down the road, we'll clear out circuits that are pending to close */
connection_stop_writing(conn);
return 0;
default:
log_fn(LOG_DEBUG,"BUG: called in unexpected state.");
return 0;
}
return 0;
}
/*********************/
connection_t *connection_or_connect(routerinfo_t *router) {
connection_t *conn;
struct sockaddr_in router_addr;
int s;
assert(router);
if(router_is_me(router->addr, router->or_port)) {
/* this is me! don't connect to me. */
log(LOG_DEBUG,"connection_or_connect(): This is me. Skipping.");
return NULL;
}
/* this function should never be called if we're already connected to router, but */
/* check first to be sure */
conn = connection_exact_get_by_addr_port(router->addr,router->or_port);
if(conn)
return conn;
conn = connection_new(CONN_TYPE_OR);
if(!conn) {
return NULL;
}
/* set up conn so it's got all the data we need to remember */
conn->addr = router->addr;
conn->port = router->or_port;
conn->bandwidth = router->bandwidth;
conn->pkey = crypto_pk_dup_key(router->pkey);
conn->address = strdup(router->address);
s=socket(PF_INET,SOCK_STREAM,IPPROTO_TCP);
if (s < 0) {
log(LOG_ERR,"Error creating network socket.");
connection_free(conn);
return NULL;
}
fcntl(s, F_SETFL, O_NONBLOCK); /* set s to non-blocking */
memset((void *)&router_addr,0,sizeof(router_addr));
router_addr.sin_family = AF_INET;
router_addr.sin_port = htons(router->or_port);
router_addr.sin_addr.s_addr = htonl(router->addr);
log(LOG_DEBUG,"connection_or_connect() : Trying to connect to %s:%u.",router->address,router->or_port);
if(connect(s,(struct sockaddr *)&router_addr,sizeof(router_addr)) < 0){
if(errno != EINPROGRESS){
/* yuck. kill it. */
connection_free(conn);
return NULL;
} else {
/* it's in progress. set state appropriately and return. */
conn->s = s;
if(connection_add(conn) < 0) { /* no space, forget it */
connection_free(conn);
return NULL;
}
log(LOG_DEBUG,"connection_or_connect() : connect in progress.");
connection_watch_events(conn, POLLIN | POLLOUT); /* writable indicates finish, readable indicates broken link */
conn->state = OR_CONN_STATE_CLIENT_CONNECTING;
return conn;
}
}
/* it succeeded. we're connected. */
conn->s = s;
if(connection_add(conn) < 0) { /* no space, forget it */
connection_free(conn);
return NULL;
}
log(LOG_DEBUG,"connection_or_connect() : Connection to router %s:%u established.",
router->address, router->or_port);
if((options.OnionRouter && or_handshake_client_send_auth(conn) >= 0) ||
(!options.OnionRouter && or_handshake_op_send_keys(conn) >= 0))
return conn; /* success! */
/* failure */
connection_remove(conn);
connection_free(conn);
return NULL;
}
/* ********************************** */
int connection_or_create_listener(struct sockaddr_in *bindaddr) {
log(LOG_DEBUG,"connection_create_or_listener starting");
return connection_create_listener(bindaddr, CONN_TYPE_OR_LISTENER);
}
int connection_or_handle_listener_read(connection_t *conn) {
log(LOG_NOTICE,"OR: Received a connection request from a router. Attempting to authenticate.");
return connection_handle_listener_read(conn, CONN_TYPE_OR, OR_CONN_STATE_SERVER_AUTH_WAIT);
}
/* ***************** */
/* Helper functions to implement handshaking */
#define FLAGS_LEN 2
#define BANDWIDTH_LEN 4
#define KEY_LEN 16
#define ADDR_LEN 4
#define PORT_LEN 2
#define PKEY_LEN 128
static int
or_handshake_op_send_keys(connection_t *conn) {
unsigned char message[FLAGS_LEN + BANDWIDTH_LEN + KEY_LEN + KEY_LEN];
unsigned char cipher[PKEY_LEN];
int retval;
assert(conn && conn->type == CONN_TYPE_OR);
conn->bandwidth = DEFAULT_BANDWIDTH_OP;
/* generate random keys */
if(crypto_cipher_generate_key(conn->f_crypto) ||
crypto_cipher_generate_key(conn->b_crypto)) {
log(LOG_ERR,"Cannot generate a secure 3DES key.");
return -1;
}
log(LOG_DEBUG,"or_handshake_op_send_keys() : Generated 3DES keys.");
/* compose the message */
*(uint16_t *)(message) = htons(HANDSHAKE_AS_OP);
*(uint32_t *)(message+FLAGS_LEN) = htonl(conn->bandwidth);
memcpy((void *)(message+FLAGS_LEN+BANDWIDTH_LEN),
(void *)conn->f_crypto->key, 16);
memcpy((void *)(message+FLAGS_LEN+BANDWIDTH_LEN+KEY_LEN),
(void *)conn->b_crypto->key, 16);
/* encrypt with RSA */
if(crypto_pk_public_encrypt(conn->pkey, message, sizeof(message), cipher, RSA_PKCS1_PADDING) < 0) {
log(LOG_ERR,"or_handshake_op_send_keys(): Public key encryption failed.");
return -1;
}
log(LOG_DEBUG,"or_handshake_op_send_keys() : Encrypted authentication message.");
/* send message */
if(connection_write_to_buf(cipher, PKEY_LEN, conn) < 0) {
log(LOG_DEBUG,"or_handshake_op_send_keys(): my outbuf is full. Oops.");
return -1;
}
retval = connection_flush_buf(conn);
if(retval < 0) {
log(LOG_DEBUG,"or_handshake_op_send_keys(): bad socket while flushing.");
return -1;
}
if(retval > 0) {
/* still stuff on the buffer. */
conn->state = OR_CONN_STATE_OP_SENDING_KEYS;
connection_watch_events(conn, POLLOUT | POLLIN);
return 0;
}
/* it finished sending */
log(LOG_DEBUG,"or_handshake_op_send_keys(): Finished sending authentication message.");
return or_handshake_op_finished_sending_keys(conn);
}
static int
or_handshake_op_finished_sending_keys(connection_t *conn) {
/* do crypto initialization, etc */
conn_or_init_crypto(conn);
connection_or_set_open(conn);
circuit_n_conn_open(conn); /* send the pending onion(s) */
return 0;
}
static int
or_handshake_client_send_auth(connection_t *conn) {
int retval;
char buf[FLAGS_LEN+ADDR_LEN+PORT_LEN+ADDR_LEN+
PORT_LEN+KEY_LEN+KEY_LEN+BANDWIDTH_LEN];
char cipher[PKEY_LEN];
struct sockaddr_in me; /* my router identity */
assert(conn);
if(learn_my_address(&me) < 0)
return -1;
/* generate random keys */
if(crypto_cipher_generate_key(conn->f_crypto) ||
crypto_cipher_generate_key(conn->b_crypto)) {
log(LOG_ERR,"Cannot generate a secure DES key.");
return -1;
}
log(LOG_DEBUG,"or_handshake_client_send_auth() : Generated DES keys.");
/* generate first message */
*(uint16_t*)buf = htons(HANDSHAKE_AS_OR);
*(uint32_t*)(buf+FLAGS_LEN) = me.sin_addr.s_addr; /* local address, network order */
*(uint16_t*)(buf+FLAGS_LEN+ADDR_LEN) = me.sin_port; /* local port, network order */
*(uint32_t*)(buf+FLAGS_LEN+ADDR_LEN+PORT_LEN) = htonl(conn->addr); /* remote address */
*(uint16_t*)(buf+FLAGS_LEN+ADDR_LEN+PORT_LEN+ADDR_LEN) = htons(conn->port); /* remote port */
memcpy(buf+FLAGS_LEN+ADDR_LEN+PORT_LEN+ADDR_LEN+PORT_LEN,
conn->f_crypto->key,16); /* keys */
memcpy(buf+FLAGS_LEN+ADDR_LEN+PORT_LEN+ADDR_LEN+PORT_LEN+KEY_LEN,
conn->b_crypto->key,16);
*(uint32_t *)(buf+FLAGS_LEN+ADDR_LEN+PORT_LEN+ADDR_LEN+PORT_LEN+
KEY_LEN+KEY_LEN) = htonl(conn->bandwidth); /* max link utilisation */
log(LOG_DEBUG,"or_handshake_client_send_auth() : Generated first authentication message.");
/* encrypt message */
retval = crypto_pk_public_encrypt(conn->pkey, buf, sizeof(buf), cipher,RSA_PKCS1_PADDING);
if (retval == -1) /* error */
{
log(LOG_ERR,"Public-key encryption failed during authentication to %s:%u.",conn->address,conn->port);
log(LOG_DEBUG,"or_handshake_client_send_auth() : Reason : %s.",crypto_perror());
return -1;
}
log(LOG_DEBUG,"or_handshake_client_send_auth() : Encrypted authentication message.");
/* send message */
if(connection_write_to_buf(cipher, PKEY_LEN, conn) < 0) {
log(LOG_DEBUG,"or_handshake_client_send_auth(): my outbuf is full. Oops.");
return -1;
}
retval = connection_flush_buf(conn);
if(retval < 0) {
log(LOG_DEBUG,"or_handshake_client_send_auth(): bad socket while flushing.");
return -1;
}
if(retval > 0) {
/* still stuff on the buffer. */
conn->state = OR_CONN_STATE_CLIENT_SENDING_AUTH;
connection_watch_events(conn, POLLOUT | POLLIN);
return 0;
}
/* it finished sending */
log(LOG_DEBUG,"or_handshake_client_send_auth(): Finished sending authentication message.");
conn->state = OR_CONN_STATE_CLIENT_AUTH_WAIT;
connection_watch_events(conn, POLLIN);
return 0;
}
static int
or_handshake_client_process_auth(connection_t *conn) {
char buf[128]; /* only 56 of this is expected to be used */
char cipher[128];
uint32_t bandwidth;
int retval;
struct sockaddr_in me; /* my router identity */
assert(conn);
if(learn_my_address(&me) < 0)
return -1;
if(conn->inbuf_datalen < 128) /* entire response available? */
return 0; /* not yet */
if(connection_fetch_from_buf(cipher,128,conn) < 0) {
return -1;
}
log(LOG_DEBUG,"or_handshake_client_process_auth() : Received auth.");
/* decrypt response */
retval = crypto_pk_private_decrypt(get_privatekey(), cipher, 128, buf, RSA_PKCS1_PADDING);
if (retval == -1)
{
log(LOG_ERR,"Public-key decryption failed during authentication to %s:%u.",
conn->address,conn->port);
log(LOG_DEBUG,"or_handshake_client_process_auth() : Reason : %s.",
crypto_perror());
return -1;
}
else if (retval != 56)
{
log(LOG_ERR,"client_process_auth: incorrect response from router %s:%u.",
conn->address,conn->port);
return -1;
}
log(LOG_DEBUG,"or_handshake_client_process_auth() : Decrypted response.");
/* check validity */
if ( (*(uint32_t*)buf != me.sin_addr.s_addr) || /* local address, network order */
(*(uint16_t*)(buf+4) != me.sin_port) || /* local port, network order */
(ntohl(*(uint32_t*)(buf+6)) != conn->addr) || /* remote address */
(ntohs(*(uint16_t*)(buf+10)) != conn->port) ) { /* remote port */
log(LOG_ERR,"client_process_auth: Router %s:%u: bad address info.", conn->address,conn->port);
return -1;
}
if ( (memcmp(conn->f_crypto->key, buf+12, 16)) || /* keys */
(memcmp(conn->b_crypto->key, buf+28, 16)) ) {
log(LOG_ERR,"client_process_auth: Router %s:%u: bad key info.",conn->address,conn->port);
return -1;
}
log(LOG_DEBUG,"or_handshake_client_process_auth() : Response valid.");
/* update link info */
bandwidth = ntohl(*(uint32_t *)(buf+44));
if (conn->bandwidth > bandwidth)
conn->bandwidth = bandwidth;
/* reply is just local addr/port, remote addr/port, nonce */
memcpy(buf+12, buf+48, 8);
/* encrypt reply */
retval = crypto_pk_public_encrypt(conn->pkey, buf, 20, cipher,RSA_PKCS1_PADDING);
if (retval == -1) /* error */
{
log(LOG_ERR,"Public-key encryption failed during authentication to %s:%u.",conn->address,conn->port);
log(LOG_DEBUG,"or_handshake_client_process_auth() : Reason : %s.",crypto_perror());
return -1;
}
/* send the message */
if(connection_write_to_buf(cipher, 128, conn) < 0) {
log(LOG_DEBUG,"or_handshake_client_process_auth(): my outbuf is full. Oops.");
return -1;
}
retval = connection_flush_buf(conn);
if(retval < 0) {
log(LOG_DEBUG,"or_handshake_client_process_auth(): bad socket while flushing.");
return -1;
}
if(retval > 0) {
/* still stuff on the buffer. */
conn->state = OR_CONN_STATE_CLIENT_SENDING_NONCE;
connection_watch_events(conn, POLLOUT | POLLIN);
/* return(connection_process_inbuf(conn)); process the rest of the inbuf */
return 0;
}
/* it finished sending */
log(LOG_DEBUG,"or_handshake_client_process_auth(): Finished sending nonce.");
conn_or_init_crypto(conn);
connection_or_set_open(conn);
return connection_process_inbuf(conn); /* process the rest of the inbuf */
}
/*
*
* auth handshake, as performed by OR *receiving* the connection
*
*/
static int
or_handshake_server_process_auth(connection_t *conn) {
int retval;
char buf[128]; /* 50 of this is expected to be used for OR, 38 for OP */
char cipher[128];
unsigned char iv[16];
uint32_t addr;
uint16_t port;
uint32_t bandwidth;
routerinfo_t *router;
assert(conn);
log(LOG_DEBUG,"or_handshake_server_process_auth() entered.");
if(conn->inbuf_datalen < 128) /* entire response available? */
return 0; /* not yet */
if(connection_fetch_from_buf(cipher,128,conn) < 0) {
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_auth() : Received auth.");
/* decrypt response */
retval = crypto_pk_private_decrypt(get_privatekey(), cipher, 128, buf, RSA_PKCS1_PADDING);
if (retval == -1) {
log(LOG_ERR,"or_handshake_server_process_auth: Public-key decryption failed.");
log(LOG_DEBUG,"or_handshake_server_process_auth() : Reason : %s.",
crypto_perror());
return -1;
}
if (retval == 50) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): Decrypted OR-style auth message.");
if(ntohs(*(uint16_t*)buf) != HANDSHAKE_AS_OR) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): ...but wasn't labelled OR. Dropping.");
return -1;
}
/* identify the router */
addr = ntohl(*(uint32_t*)(buf+2)); /* save the IP address */
port = ntohs(*(uint16_t*)(buf+6)); /* save the port */
router = router_get_by_addr_port(addr,port);
if (!router) {
log(LOG_DEBUG,"or_handshake_server_process_auth() : unknown router '%s:%d'. Will drop.", conn->address, port);
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_auth() : Router identified as %s:%u.",
router->address,router->or_port);
if(connection_exact_get_by_addr_port(addr,port)) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): That router is already connected. Dropping.");
return -1;
}
/* save keys */
crypto_cipher_set_key(conn->b_crypto,buf+14);
crypto_cipher_set_key(conn->f_crypto,buf+30);
/* update link info */
bandwidth = ntohl(*(uint32_t *)(buf+46));
conn->bandwidth = router->bandwidth;
if (conn->bandwidth > bandwidth)
conn->bandwidth = bandwidth;
/* copy all relevant info to conn */
conn->addr = router->addr, conn->port = router->or_port;
conn->pkey = crypto_pk_dup_key(router->pkey);
conn->address = strdup(router->address);
/* generate a nonce */
retval = crypto_rand(8, conn->nonce);
if (retval) { /* error */
log(LOG_ERR,"Cannot generate a nonce.");
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_auth(): Nonce generated.");
memmove(buf, buf+2, 44);
*(uint32_t *)(buf+44) = htonl(conn->bandwidth); /* send max link utilisation */
memcpy(buf+48,conn->nonce,8); /* append the nonce to the end of the message */
/* encrypt message */
retval = crypto_pk_public_encrypt(conn->pkey, buf, 56, cipher,RSA_PKCS1_PADDING);
if (retval == -1) { /* error */
log(LOG_ERR,"Public-key encryption failed during authentication to %s:%u.",conn->address,conn->port);
log(LOG_DEBUG,"or_handshake_server_process_auth() : Reason : %s.",crypto_perror());
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_auth() : Reply encrypted.");
/* send message */
if(connection_write_to_buf(cipher, 128, conn) < 0) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): my outbuf is full. Oops.");
return -1;
}
retval = connection_flush_buf(conn);
if(retval < 0) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): bad socket while flushing.");
return -1;
}
if(retval > 0) {
/* still stuff on the buffer. */
conn->state = OR_CONN_STATE_SERVER_SENDING_AUTH;
connection_watch_events(conn, POLLOUT | POLLIN);
return 0;
}
/* it finished sending */
log(LOG_DEBUG,"or_handshake_server_process_auth(): Finished sending auth.");
conn->state = OR_CONN_STATE_SERVER_NONCE_WAIT;
connection_watch_events(conn, POLLIN);
return 0;
}
if(retval == 38) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): Decrypted OP-style auth message.");
if(ntohs(*(uint16_t*)buf) != HANDSHAKE_AS_OP) {
log(LOG_DEBUG,"or_handshake_server_process_auth(): ...but wasn't labelled OP. Dropping.");
return -1;
}
conn->bandwidth = ntohl(*((uint32_t *)(buf+2)));
log(LOG_DEBUG,"or_handshake_server_process_auth(): Bandwidth %d requested.",conn->bandwidth);
crypto_cipher_set_key(conn->b_crypto, buf+6);
crypto_cipher_set_key(conn->f_crypto, buf+22);
memset(iv, 0, 16);
crypto_cipher_set_iv(conn->b_crypto, iv);
crypto_cipher_set_iv(conn->f_crypto, iv);
crypto_cipher_encrypt_init_cipher(conn->b_crypto);
crypto_cipher_decrypt_init_cipher(conn->f_crypto);
conn->state = OR_CONN_STATE_OPEN;
connection_init_timeval(conn);
connection_watch_events(conn, POLLIN);
return connection_process_inbuf(conn); /* in case they sent some cells along with the keys */
}
log(LOG_ERR,"or_handshake_server_process_auth(): received an incorrect authentication request.");
return -1;
}
static int
or_handshake_server_process_nonce(connection_t *conn) {
char buf[128];
char cipher[128];
int retval;
struct sockaddr_in me; /* my router identity */
assert(conn);
if(learn_my_address(&me) < 0)
return -1;
if(conn->inbuf_datalen < 128) /* entire response available? */
return 0; /* not yet */
if(connection_fetch_from_buf(cipher,128,conn) < 0) {
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_nonce() : Received auth.");
/* decrypt response */
retval = crypto_pk_private_decrypt(get_privatekey(), cipher, 128, buf,RSA_PKCS1_PADDING);
if (retval == -1)
{
log(LOG_ERR,"Public-key decryption failed during authentication to %s:%u.",
conn->address,conn->port);
log(LOG_DEBUG,"or_handshake_server_process_nonce() : Reason : %s.",
crypto_perror());
return -1;
}
else if (retval != 20)
{
log(LOG_ERR,"server_process_nonce: incorrect response from router %s:%u.",
conn->address,conn->port);
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_nonce() : Response decrypted.");
/* check validity */
if ((ntohl(*(uint32_t*)buf) != conn->addr) || /* remote address */
(ntohs(*(uint16_t*)(buf+4)) != conn->port) || /* remote port */
(*(uint32_t*)(buf+6) != me.sin_addr.s_addr) || /* local address, network order */
(*(uint16_t*)(buf+10) != me.sin_port) || /* local port, network order */
(memcmp(conn->nonce,buf+12,8))) /* nonce */
{
log(LOG_ERR,"server_process_nonce: Router %s:%u gave bad response.",conn->address,conn->port);
return -1;
}
log(LOG_DEBUG,"or_handshake_server_process_nonce() : Response valid. Authentication complete.");
conn_or_init_crypto(conn);
connection_or_set_open(conn);
return connection_process_inbuf(conn); /* process the rest of the inbuf */
}
/*********************/
static void
connection_or_set_open(connection_t *conn) {
conn->state = OR_CONN_STATE_OPEN;
directory_set_dirty();
connection_init_timeval(conn);
connection_watch_events(conn, POLLIN);
}
static void
conn_or_init_crypto(connection_t *conn) {
//int x;
unsigned char iv[16];
assert(conn);
memset((void *)iv, 0, 16);
crypto_cipher_set_iv(conn->f_crypto, iv);
crypto_cipher_set_iv(conn->b_crypto, iv);
crypto_cipher_encrypt_init_cipher(conn->f_crypto);
crypto_cipher_decrypt_init_cipher(conn->b_crypto);
/* always encrypt with f, always decrypt with b */
}
/*
Local Variables:
mode:c
indent-tabs-mode:nil
c-basic-offset:2
End:
*/
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