contact_ops.c

用来作为linux中SIP SERVER,完成VOIP网络电话中服务器的功能

	else			/* we do not have  <> */
	{
		start = q_memchr (string, ':', uri.len);
		if (start == NULL)
			return -5;
		if (start - pos < 3)
			return -6;
		start = start - 3;
		end = string + uri.len;
	}
	memset(format,0,sizeof(struct uri_format));
	format->first = start - string + 4;	/*sip: */
	format->second = end - string;
	/* --------------------------testing ------------------------------- */
	/* sip:gva@pass@10.0.0.1;;transport=udp>;expires=2 INCORECT BEHAVIOR OF parse_uri,myfunction works good */
	foo = parse_uri (start, end - start, &sipUri);
	if (foo != 0)
	{
		LOG(L_ERR,"ERROR: encode2format: parse_uri failed on [%.*s].Code %d \n",uri.len,uri.s,foo);
#ifdef DEBUG
		fprintf (stdout, "PARSING uri with parse uri not ok %d\n", foo);
#endif
		return foo-10;
	}

	
	format->username = sipUri.user;
	format->password = sipUri.passwd;
	format->ip = sipUri.host;
	format->port = sipUri.port;
	format->protocol = sipUri.transport_val;
	
#ifdef DEBUG	
	fprintf (stdout, "transport=[%.*s] transportval=[%.*s]\n", sipUri.transport.len,sipUri.transport.s,sipUri.transport_val.len,sipUri.transport_val.s);
	fprintf(stdout,"First %d,second %d\n",format->first,format->second);
	#endif
	
	return 0;

}


int
encode_uri (str uri, char *encoding_prefix, char *public_ip,char separator, str * result)
{
	struct uri_format format;
	char *pos;
	int foo,res;

	
	result->s = NULL;
	result->len = 0;
	if (uri.len <= 1)
		return -1;	/* no contact or an invalid one */
	if (public_ip == NULL) 
		{
			LOG(L_ERR,"ERROR: encode_uri: Invalid NULL value for public_ip parameter\n");
			return -2;
		}
#ifdef DEBUG
	fprintf (stdout, "Primit cerere de encodare a [%.*s] cu %s-%s\n", uri.len,uri.s, encoding_prefix, public_ip);
#endif
	fflush (stdout);
	foo = encode2format (uri, &format);
	if (foo < 0)
		{
		LOG(L_ERR,"ERROR: encode_uri: Unable to encode Contact URI [%.*s].Return code %d\n",uri.len,uri.s,foo);
		return foo - 20;
		}
#ifdef DEBUG
	fprintf(stdout,"user=%.*s ip=%.*s port=%.*s protocol=%.*s\n",format.username.len,format.username.s,format.ip.len,format.ip.s,
	     format.port.len,format.port.s,format.protocol.len,format.protocol.s);   
#endif

	/* a complete uri would be sip:username@ip:port;transport=protocol goes to
	 * sip:enc_pref*username*ip*port*protocol@public_ip
	 */

	foo = 1;		/*strlen(separator); */
	result->len = format.first + uri.len - format.second +	//ar trebui sa sterg 1
		strlen (encoding_prefix) + foo +
		format.username.len + foo +
		format.password.len + foo +
		format.ip.len + foo + format.port.len + foo +
		format.protocol.len + 1 + strlen (public_ip);
	/* adding one comes from @ */
	result->s = pkg_malloc (result->len);
	pos = result->s;
	if (pos == NULL)
		{
#ifdef DEBUG
			fprintf (stdout, "Unable to alloc result [%d] end=%d\n",result->len, format.second);
#endif
			LOG(L_ERR,"ERROR: encode_uri:Unable to alloc memory\n");
			return -3;
		}
#ifdef DEBUG
	fprintf (stdout, "[pass=%d][Allocated %d bytes][first=%d][lengthsec=%d]\nAdding [%d] ->%.*s\n",format.password.len,result->len,format.first,uri.len-format.second,format.first, format.first,uri.s);fflush (stdout);
#endif
	 	
	res = snprintf(pos,result->len,"%.*s%s%c%.*s%c%.*s%c%.*s%c%.*s%c%.*s@",format.first,uri.s,encoding_prefix,separator,
	format.username.len,format.username.s,separator,format.password.len,format.password.s,
	separator,format.ip.len,format.ip.s,separator,format.port.len,format.port.s,separator,format.protocol.len,format.protocol.s);

	if ((res < 0 )||(res>result->len)) 
		{
			LOG(L_ERR,"ERROR: encode_uri: Unable to construct new uri.\n");
			if (result->s != NULL) pkg_free(result->s);
			return -4;
		}
#ifdef DEBUG
	fprintf(stdout,"res= %d\npos=%s\n",res,pos);
#endif
	pos = pos + res ;/* overwriting the \0 from snprintf */
	memcpy (pos, public_ip, strlen (public_ip));
	pos = pos + strlen (public_ip);
	memcpy (pos, uri.s + format.second, uri.len - format.second);

#ifdef DEBUG	
	fprintf (stdout, "Adding2 [%d] ->%.*s\n", uri.len - format.second,uri.len - format.second, uri.s + format.second);
	fprintf (stdout, "NEW NEW uri is->[%.*s]\n", result->len, result->s);
#endif

	/* Because called parse_uri format contains pointers to the inside of msg,must not deallocate */

	return 0;
}


int
decode2format (str uri, char separator, struct uri_format *format)
{
	char *start, *end, *pos,*lastpos;
	str tmp;
	enum {EX_PREFIX=0,EX_USER,EX_PASS,EX_IP,EX_PORT,EX_PROT,EX_FINAL} state;

	//memset (format, 0, sizeof ((struct uri_format)));

	if (uri.s == NULL)
		{
		LOG(L_ERR,"ERROR: decode2format: Invalid parameter uri.It is NULL\n");
		return -1;
		}
	/* sip:enc_pref*username*password*ip*port*protocol@public_ip */
	
	start = q_memchr (uri.s, ':', uri.len);
	if (start == NULL)
	{
		LOG(L_ERR,"ERROR: decode2format: Invalid SIP uri.Missing :\n");
		return -2;
	}			/* invalid uri */
	start = start + 1;	/* jumping over sip: ATENTIE LA BUFFER OVERFLOW DACA E DOAR sip: */
	format->first = start - uri.s;
	
	/* start */

	end = q_memchr(start,'@',uri.len-(start-uri.s));
	if (end == NULL) 
		{
		LOG(L_ERR,"ERROR: decode2format: Invalid SIP uri.Missing @\n");
		return -3;/* no host address found */
		}

#ifdef DEBUG
		fprintf (stdout, "Decoding %.*s\n",end-start,start);
#endif
	
	state = EX_PREFIX;
	lastpos = start;
	
	for (pos = start;pos<end;pos++)
		{
			if (*pos == separator)
				{
					/* we copy between lastpos and pos */
					tmp.len = pos - lastpos;
					if (tmp.len>0) tmp.s = lastpos;
						else tmp.s = NULL;
					switch (state)
						{
							case EX_PREFIX: state = EX_USER;break;
							case EX_USER:format->username = tmp;state = EX_PASS;break;
							case EX_PASS:format->password = tmp;state = EX_IP;break;
							case EX_IP:format->ip = tmp;state = EX_PORT;break;
							case EX_PORT:format->port = tmp;state = EX_PROT;break;
							default:
								{
								/* this should not happen, we should find @ not separator */
								return -4;
								break;
								}
						}
						
					lastpos = pos+1;
				
				}
			else
			if (((*pos) == '>')||(*pos == ';'))
				{
				/* invalid chars inside username part */
				return -5;
				}
		}
		
		
	/* we must be in state EX_PROT and protocol is between lastpos and end@ */
	if (state != EX_PROT) return -6;
	format->protocol.len = end - lastpos;
	if (format->protocol.len>0) format->protocol.s = lastpos;
		else format->protocol.s = NULL;
	/* I should check perhaps that 	after @ there is something */
		
#ifdef DEBUG
		fprintf (stdout, "username=%.*s\n", format->username.len,format->username.s);
		fprintf (stdout, "password=%.*s\n", format->password.len,format->password.s);
		fprintf (stdout, "ip=%.*s\n", format->ip.len, format->ip.s);
		fprintf (stdout, "port=%.*s\n", format->port.len,format->port.s);
		fprintf (stdout, "protocol=%.*s\n", format->protocol.len,format->protocol.s);
#endif

	/* looking for the end of public ip */
	start = end;/*we are now at @ */
	for(pos = start;pos<uri.s+uri.len;pos++)
		{
			if ((*pos == ';')||(*pos == '>'))
				{
				/* found end */
				format->second = pos - uri.s;
				return 0;
				}
		}
	/* if we are here we did not find > or ; */
	format->second = uri.len;
	return 0;	
	
}


int
decode_uri (str uri, char separator, str * result)
{
	char *pos;
	struct uri_format format;
	int foo;

	result->s = NULL;
	result->len = 0;

	if ((uri.len <= 0) || (uri.s == NULL))
		{
		LOG(L_ERR,"ERROR: decode_uri: Invalid value for uri\n");
		return -1;
		}

	foo = decode2format (uri, separator, &format);
	if (foo < 0)
		{
		LOG(L_ERR,"ERROR: decode_uri: Error decoding Contact uri .Error code %d\n",foo);
		return foo - 20;
		}
	/* sanity check */
	if (format.ip.len <= 0)
		{
			LOG(L_ERR,"ERROR: decode_uri: Unable to decode host address \n");
			return -2;/* should I quit or ignore ? */
		}			

	if ((format.password.len > 0) && (format.username.len <= 0))
		{
			LOG(L_ERR,"ERROR: decode_uri: Password decoded but no username available\n");
			return -3;
		}
		
	/* a complete uri would be sip:username:password@ip:port;transport=protocol goes to
	 * sip:enc_pref#username#password#ip#port#protocol@public_ip
	 */
	result->len = format.first + (uri.len - format.second);	/* not NULL terminated */
	if (format.username.len > 0) result->len += format.username.len + 1;	//: or @
	if (format.password.len > 0) result->len += format.password.len + 1;	//@
		
	/* if (format.ip.len > 0) */	     result->len += format.ip.len;
		
	if (format.port.len > 0)     result->len += 1 + format.port.len;	//:
	if (format.protocol.len > 0) result->len += 1 + 10 + format.protocol.len;	//;transport=
#ifdef DEBUG
	fprintf (stdout, "Result size is %d.Original Uri size is %d\n",result->len, uri.len);
#endif
	
	/* adding one comes from * */
	result->s = pkg_malloc (result->len);
	if (result->s == NULL)
		{
			LOG(L_ERR,"ERROR: decode_contact: Unable to allocate memory\n");
			return -4;
		}
	pos = result->s;
#ifdef DEBUG
	fprintf (stdout, "Adding [%d] ->%.*s\n", format.first, format.first,uri.s);fflush (stdout);
#endif
	memcpy (pos, uri.s, format.first);	/* till sip: */
	pos = pos + format.first;
	
	if (format.username.len > 0)
	{
		memcpy (pos, format.username.s, format.username.len);
		pos = pos + format.username.len;
		if (format.password.len > 0)
			memcpy (pos, ":", 1);
		else
			memcpy (pos, "@", 1);
		pos = pos + 1;
	}
	if (format.password.len > 0)
	{
		memcpy (pos, format.password.s, format.password.len);
		pos = pos + format.password.len;
		memcpy (pos, "@", 1);
		pos = pos + 1;
	}
	/* if (format.ip.len > 0) */

		memcpy (pos, format.ip.s, format.ip.len);
		pos = pos + format.ip.len;
	
	if (format.port.len > 0)
	{
		memcpy (pos, ":", 1);
		pos = pos + 1;
		memcpy (pos, format.port.s, format.port.len);
		pos = pos + format.port.len;
	}
	if (format.protocol.len > 0)
	{
		memcpy (pos, ";transport=", 11);
		pos = pos + 11;
		memcpy (pos, format.protocol.s, format.protocol.len);
		pos = pos + format.protocol.len;
	}

#ifdef DEBUG
	fprintf (stdout, "Adding2 [%d] ->%.*s\n", uri.len - format.second,uri.len - format.second, uri.s + format.second);fflush (stdout);
#endif

	memcpy (pos, uri.s + format.second, uri.len - format.second);	/* till end: */

#ifdef DEBUG
	fprintf (stdout, "New decoded uri is->[%.*s]\n", result->len,result->s);
#endif

	return 0;
}