Folded cell.? into src/or

svn:r64
This commit is contained in:
Roger Dingledine 2002-07-19 18:48:28 +00:00
parent fc0e2a34ec
commit 5c0edf6d54
4 changed files with 115 additions and 25 deletions

View File

@ -4,24 +4,97 @@
#include "or.h"
int check_sane_cell(cell_t *cell) {
static cell_t *new_create_cell(uint16_t aci, unsigned char length, unsigned char *buf)
{
cell_t *c = NULL;
int retval;
assert(cell);
#if 0 /* actually, the aci is 0 for padding cells */
if(cell->aci == 0) {
log(LOG_DEBUG,"check_sane_cell(): Cell has aci=0. Dropping.");
return -1;
}
#endif
#if 0 /* actually, the length is sometimes encrypted. so it's ok. */
if(cell->length > 120) {
log(LOG_DEBUG,"check_sane_cell(): Cell claims to have payload length %d. Dropping.",cell->length);
return -1;
}
#endif
return 0; /* looks good */
if ((aci) && (buf) && (length <= CELL_PAYLOAD_SIZE)) /* valid parameters */
{
c = (cell_t *)malloc(sizeof(cell_t));
if (!c) /* malloc() error */
return NULL;
c->command = CELL_CREATE;
c->aci = aci;
c->length = length;
c->seq = 0;
memcpy((void *)c->payload, (void *)buf, length);
retval = RAND_pseudo_bytes((unsigned char *)(c->payload+length),CELL_PAYLOAD_SIZE-length);
if (retval == -1) /* RAND_pseudo_bytes() error */
{
free((void *)c);
return NULL;
} /* RAND_pseudo_bytes() error */
return c;
} /* valid parameters */
else /* invalid parameters */
return NULL;
}
int pack_create(uint16_t aci, unsigned char *onion, uint32_t onionlen, unsigned char **cellbuf, unsigned int *cellbuflen)
{
cell_t *c;
unsigned char *buf;
unsigned int buflen;
unsigned int cells;
unsigned int dataleft;
unsigned int i;
assert(aci && onion && onionlen && cellbuf && cellbuflen);
/* copy the onion into a buffer, prepend with onion length */
buflen = onionlen+4;
buf = (unsigned char *)malloc(buflen);
if (!buf) /* malloc() error */
return -1;
log(LOG_DEBUG,"pack_create() : Setting onion length to %u.",onionlen);
*(uint32_t*)buf = htonl(onionlen);
memcpy((void *)(buf+4),(void *)onion,onionlen);
/* calculate number of cells required */
if (buflen%CELL_PAYLOAD_SIZE == 0)
cells = buflen/CELL_PAYLOAD_SIZE;
else
cells = buflen/CELL_PAYLOAD_SIZE+1;
/* allocate memory for the cells */
*cellbuflen = cells * sizeof(cell_t);
*cellbuf = malloc(*cellbuflen);
if (!*cellbuf) /* malloc() error */
return -1;
log(LOG_DEBUG,"pack_create() : Allocated memory for %u cells.",cells);
/* create cells one by one */
dataleft = buflen;
for(i=0; i<cells; i++)
{
log(LOG_DEBUG,"pack_create() : Packing %u bytes of data.",dataleft);
if (dataleft >= CELL_PAYLOAD_SIZE)
{
c = new_create_cell(aci,CELL_PAYLOAD_SIZE,buf+i*CELL_PAYLOAD_SIZE);
dataleft -= CELL_PAYLOAD_SIZE;
}
else
c = new_create_cell(aci,dataleft,buf+i*CELL_PAYLOAD_SIZE);
if (!c) /* cell creation failed */
{
free((void *)*cellbuf);
return -1;
} /* cell creation failed */
log(LOG_DEBUG,"pack_create() : new_create_cell succeeded; copying the cell into output buffer");
/* cell has been created, now copy into buffer */
memcpy((void *)(*cellbuf+i*sizeof(cell_t)),(void *)c,sizeof(cell_t));
free((void *)c);
}
free(buf);
return 0;
}

View File

@ -6,9 +6,6 @@
void command_process_cell(cell_t *cell, connection_t *conn) {
if(check_sane_cell(cell) < 0)
return;
switch(cell->command) {
case CELL_PADDING:
/* do nothing */

View File

@ -621,14 +621,14 @@ int connection_consider_sending_sendme(connection_t *conn) {
if(circ->n_conn == conn) { /* we're at an exit */
if(circ->p_receive_window < RECEIVE_WINDOW_START-RECEIVE_WINDOW_INCREMENT) {
log(LOG_DEBUG,"connection_consider_sending_sendme(): Queueing sendme back.");
log(LOG_DEBUG,"connection_consider_sending_sendme(): Outbuf %d, Queueing sendme back.", conn->outbuf_flushlen);
circ->p_receive_window += RECEIVE_WINDOW_INCREMENT;
sendme.aci = circ->p_aci;
return connection_write_cell_to_buf(&sendme, circ->p_conn); /* (clobbers sendme) */
}
} else { /* we're at an AP */
if(circ->n_receive_window < RECEIVE_WINDOW_START-RECEIVE_WINDOW_INCREMENT) {
log(LOG_DEBUG,"connection_consider_sending_sendme(): Queueing sendme forward.");
log(LOG_DEBUG,"connection_consider_sending_sendme(): Outbuf %d, Queueing sendme forward.", conn->outbuf_flushlen);
circ->n_receive_window += RECEIVE_WINDOW_INCREMENT;
sendme.aci = circ->n_aci;
return connection_write_cell_to_buf(&sendme, circ->n_conn); /* (clobbers sendme) */

View File

@ -29,7 +29,6 @@
#include <openssl/evp.h>
#include <openssl/rand.h>
#include "../common/cell.h"
#include "../common/config.h"
#include "../common/key.h"
#include "../common/log.h"
@ -115,8 +114,29 @@
#define RECEIVE_WINDOW_START 100
#define RECEIVE_WINDOW_INCREMENT 10
/* cell commands */
#define CELL_PADDING 0
#define CELL_CREATE 1
#define CELL_DATA 2
#define CELL_DESTROY 3
#define CELL_ACK 4
#define CELL_NACK 5
#define CELL_SENDME 6
#define CELL_PAYLOAD_SIZE 120
typedef uint16_t aci_t;
/* cell definition */
typedef struct
{
aci_t aci; /* Anonymous Connection Identifier */
unsigned char command;
unsigned char length; /* of payload if data cell, else value of sendme */
uint32_t seq; /* sequence number */
unsigned char payload[120];
} cell_t;
typedef struct
{
@ -342,7 +362,7 @@ int fetch_from_buf(char *string, size_t string_len,
/********************************* cell.c ***************************/
int check_sane_cell(cell_t *cell);
int pack_create(uint16_t aci, unsigned char *onion, uint32_t onionlen, unsigned char **cellbuf, unsigned int *cellbuflen);
/********************************* circuit.c ***************************/