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/**
* ss.c
* Standard structure processing.
*
* Matej Pfajfar <mp292@cam.ac.uk>
*/
/*
* Changes :
* $Log$
* Revision 1.1 2002/06/26 22:45:50 arma
* Initial revision
*
* Revision 1.1 2002/04/02 14:28:01 badbytes
* Final finishes.
*
*/
#include <malloc.h>
#include <unistd.h>
#include "../common/log.h"
#include "../common/version.h"
#include "../common/utils.h"
#include "ss.h"
/* read the standard structure, check if it's acceptable and send an appropriate error code
* Returns :
* -1 processing error
* 0 OK
* 1 no error, but standard structure rejected
*/
int process_ss(int s, struct timeval *conn_toutp, ss_t **ssp, char **addrp, int *addrlenp, char **portp, int *portlenp)
{
int retval = 0;
int len = 0; /* number of bytes read */
ss_t *ss; /* standard structure */
char errcode = SS_ERROR_SUCCESS; /* error code which we send back to the client */
char inbuf;
char *addr = NULL; /* destination address */
int addrlen = 0;
char *port = NULL; /* destination port */
int portlen = 0;
char *tmp = NULL; /* temporary storage */
if ((!ssp) || (!addrp) || (!addrlenp) || (!portp) || (!portlenp)) /* invalid parameters */
return -1;
/* allocate memory for SS */
ss = malloc(sizeof(ss_t));
if (!ss)
{
log(LOG_ERR,"Error allocating memory.");
return -1;
}
log(LOG_DEBUG,"Allocated memory for ss.");
len = 0;
while (len < sizeof(ss_t)) /* need to make sure the entire ss is read */
{
retval = read_tout(s,(char *)ss+len,sizeof(ss_t)-len,0, conn_toutp);
if (retval <= 0)
{
free(ss);
log(LOG_ERR,"Could not receive standard structure.");
return -1;
}
len +=retval;
}
if ((ss->version == 0) || (ss->version != VERSION)) /* unsupported version */
{
log(LOG_DEBUG,"Unsupported version.");
free(ss);
errcode = SS_ERROR_VERSION_UNSUPPORTED;
write_tout(s,&errcode,1,conn_toutp);
return -1;
}
if (ss->addr_fmt != SS_ADDR_FMT_ASCII_HOST_PORT) /* unrecognized address format */
{
log(LOG_DEBUG,"Unrecognized address format.");
free(ss);
errcode = SS_ERROR_ADDR_FMT_UNSUPPORTED;
write_tout(s,&errcode,1,conn_toutp);
return -1;
}
/* allocate memory for the destination address - 512 bytes maximum */
addrlen=512;
addr = malloc(addrlen);
if (!addr)
{
free(ss);
log(LOG_ERR,"Error allocating memory.");
return -1;
}
/* now read the destination address */
len = 0;
do /* need to keep going until the entire string is read in */
{
if (len == addrlen) /* we've run out of space, abort */
{
free(ss);
free(addr);
log(LOG_ERR,"Client tried to send address > 512 characters.");
errcode = SS_ERROR_INVALID_ADDRESS;
write_tout(s,&errcode,1,conn_toutp);
return -1;
}
retval = read_tout(s,(void *)&inbuf, 1, 0, conn_toutp);
if (retval <= 0)
{
free(ss);
free(addr);
log(LOG_ERR,"Error receiving destination address.");
return -1;
}
*(addr+len) = inbuf;
len++;
} while (inbuf != 0);
/* allocate memory for the destination port - 6 bytes maximum */
portlen = 6;
port = malloc(portlen);
if (!port)
{
free(ss);
log(LOG_ERR,"Error allocating memory.");
free(addr);
return -1;
}
/* now read the destination port */
len = 0;
do /* keep going until the entire string is read in */
{
if (len == portlen) /* no more space, abort */
{
free(ss);
free(addr);
free(port);
log(LOG_ERR,"Client tried to send port > 6 characters.");
errcode = SS_ERROR_INVALID_PORT;
write_tout(s,&errcode,1,conn_toutp);
return -1;
}
retval = read_tout(s,(void *)&inbuf, 1, 0, conn_toutp);
if (retval <= 0)
{
free(ss);
free(addr);
free(port);
log(LOG_ERR,"Error receiving destination port.");
return -1;
}
*(port+len)=inbuf;
len++;
} while (inbuf != 0);
/* send a success error code back to the client */
errcode = SS_ERROR_SUCCESS;
write_tout(s,&errcode,1,conn_toutp);
/* done, now save */
addrlen = strlen(addr)+1;
tmp = addr;
addr = realloc(addr,addrlen);
/* if realloc() fails, we just ignore it and use the previously allocated memory, although this may be wasteful */
if (!addr)
addr=tmp; /* restore previous state */
else
addr[addrlen-1]=0;
portlen = strlen(port)+1;
tmp=port;
port = realloc(port,portlen);
if (!port)
port=tmp;
else
port[portlen-1]=0;
*ssp = ss;
*addrp = addr;
*addrlenp = addrlen;
*portp = port;
*portlenp = portlen;
return 0;
}
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