@@ -41,4 +41,6 @@ Low priority:

 - the same for FreeBSD and Slackware

-

+- jku: branch hash computation over canonical values

+- jku: loop checking

+- jku: try CRC as opposed to MD5

@@ -23,3 +23,5 @@ Things we have omitted for now:

 To improve:

 - too many memcpies

 - faster syncing

+

+Double-check: revire the T-state-machine

@@ -21,7 +21,9 @@ struct timer;

 #define sh_malloc( size )     malloc(size)

 #define sh_free( ptr )           free(ptr)

+/* defined in msg_parser.h

 #define get_cseq( p_msg)    ((struct cseq_body*)p_msg->cseq->parsed)

+*/

 /* always use a power of 2 for hash table size */

@@ -127,9 +127,6 @@ struct sip_msg* sip_msg_cloner( struct sip_msg *org_msg )

     /* repl_add_rm ( struct lump* ) -> have to be changed!!!!!!!  */

     new_msg->repl_add_rm  = 0;

-    /* append branch parameter */

-    new_msg->add_to_branch.s = (char *) sh_malloc( org_msg->add_to_branch.len );

-    memcpy( new_msg->add_to_branch.s, org_msg->add_to_branch.s, org_msg->add_to_branch.len );

 }

@@ -1,14 +1,12 @@

 #include "t_funcs.h"

 #include "../../dprint.h"

+#include "../../config.h"

 struct cell         *T;

 unsigned int     global_msg_id;

 struct s_table*  hash_table;

-

-

-

 int tm_startup()

 {

    /* building the hash table*/

@@ -802,6 +800,24 @@ int t_cancel_branch(unsigned int branch)

 }

+/* copy a header field to an output buffer if space allows */

+int copy_hf( char **dst, struct hdr_field* hf, char *bumper )

+{

+   int n;

+   n=hf->body.len+2+hf->name.len+CRLF_LEN;

+   if (*dst+n >= bumper ) return -1;

+   memcpy(*dst, hf->name.s, hf->name.len );

+   *dst+= hf->name.len ;

+   **dst = ':'; (*dst)++;

+   **dst = ' '; (*dst)++;

+   memcpy(*dst, hf->body.s, hf->body.len);

+   *dst+= hf->body.len;

+   memcpy( *dst, CRLF, CRLF_LEN );

+   *dst+=CRLF_LEN;

+   return 0;

+}

+  

+

 /* Builds an ACK request based on an INVITE request. ACK is send

@@ -812,106 +828,104 @@ int t_build_and_send_ACK( struct cell *Trans, unsigned int branch)

     struct sip_msg* p_msg = T->inbound_request;

     struct via_body *via;

     struct hdr_field *hdr;

-   char *ack_buf, *p;

+    char *ack_buf=NULL, *p;

     unsigned int len;

+    int n;

+

+   /* enough place for first line and Via ? */

+   if ( 4 + p_msg->first_line.u.request.uri.len + 1 + p_msg->first_line.u.request.version.len +

+	CRLF_LEN + MY_VIA_LEN + names_len[0] + 1 + port_no_str_len + MY_BRANCH_LEN  < MAX_ACK_LEN ) {

+		LOG( L_ERR, "ERROR: t_build_and_send_ACK: no place for FL/Via\n");

+		goto error;

+   }

-   ack_buf = (char *)malloc( 1024 * 10 );

+   ack_buf = (char *)malloc( MAX_ACK_LEN );

    p = ack_buf;

    /* first line */

    memcpy( p , "ACK " , 4);

    p += 4;

+

    memcpy( p , p_msg->first_line.u.request.uri.s , p_msg->first_line.u.request.uri.len );

-   p += p_msg->first_line.u.request.uri.len+1;

-   *(p++)=' ';

+   p += p_msg->first_line.u.request.uri.len;

+

+   *(p++) = ' ';

+

    memcpy( p , p_msg->first_line.u.request.version.s , p_msg->first_line.u.request.version.len );

    p += p_msg->first_line.u.request.version.len;

-   *(p++) = '\n';

+

+   memcpy( p, CRLF, CRLF_LEN );

+   p+=CRLF_LEN;

    /* insert our via */

-   memcpy( p , "Via: SIP/2.0/UDP " , 17);

-   p += 17;

+   memcpy( p , MY_VIA , MY_VIA_LEN );

+   p += MY_VIA_LEN;

+

    memcpy( p , names[0] , names_len[0] );

    p += names_len[0];

+

    *(p++) = ':';

+

    memcpy( p , port_no_str , port_no_str_len );

    p += port_no_str_len;

-   /* VIA (first we have to find the header) */

-   for( hdr=p_msg->headers ; hdr ; hdr=hdr->next  )

-      if ( hdr->type==HDR_VIA || hdr->type==HDR_FROM || hdr->type==HDR_CALLID )

-      {

-         len = (hdr->body.s+hdr->body.len) - hdr->name.s;

-         memcpy( p , p_msg->orig+(hdr->name.s-p_msg->buf) , len );

-         p += len;

-         *(p++) = '\n';

-      }

-      else if ( hdr->type==HDR_CSEQ )

-      {

-         len = (get_cseq(p_msg)->number.s+get_cseq(p_msg)->number.len) - hdr->name.s;

-         memcpy( p , p_msg->orig+(hdr->name.s-p_msg->buf) , len );

-         p += len;

-         memcpy( p , " ACK\n" , 5);

-         p += 5;

-      }

-      if ( hdr->type==HDR_TO )

-      {

-         len = (T->outbound_response[branch]->to->body.s+T->outbound_response[branch]->to->body.len) - T->outbound_response[branch]->to->name.s;

-         memcpy( p , T->outbound_response[branch]->orig+(T->outbound_response[branch]->to->name.s-T->outbound_response[branch]->buf) , len );

-         p += len;

-         *(p++) = '\n';

-      }

+   memcpy( p, MY_BRANCH, MY_BRANCH_LEN );

+   p+=MY_BRANCH_LEN;

+

+   n=snprintf( p, ack_buf + MAX_ACK_LEN - p, 

+                 ".%h.%h.%h%s",

+                 Trans->hash_index, Trans->label, branch, CRLF );

+   if (n==-1) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: not enough memory for branch\n");

+	goto error;

+   }

+   p+=n;

+

+   if (!check_transaction_quadruple( p_msg )) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: can't generate a HBH ACK if key HFs in INVITE missing\n");

+	goto error;

+   }

+

+   /* To */

+   if (copy_hf( &p, p_msg->to , ack_buf + MAX_ACK_LEN )==-1) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: no place for To\n");

+	goto error;

+   }

+   /* From */

+   if (copy_hf( &p, p_msg->from, ack_buf + MAX_ACK_LEN )==-1) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: no place for From\n");

+	goto error;

+   }

+   /* CallId */

+   if (copy_hf( &p, p_msg->callid, ack_buf + MAX_ACK_LEN )==-1) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: no place for callid\n");

+	goto error;

+   }

+   /* CSeq, EoH */

+   n=snprintf( p, ack_buf + MAX_ACK_LEN - p, 

+                 "Cseq: %*s ACK%s%s", get_cseq(p_msg)->number.len, 

+		get_cseq(p_msg)->number.s, CRLF, CRLF );

+   if (n==-1) {

+	LOG(L_ERR, "ERROR: t_build_and_send_ACK: no enough memory for Cseq\n");

+	goto error;

+   }

+   p+=n;

-   /* end of message*/

-   *(p++) = '\n';

    /* sends the ACK message to the same destination as the INVITE */

    udp_send( ack_buf, p-ack_buf, (struct sockaddr*)&(T->outbound_request[branch]->to) , sizeof(struct sockaddr_in) );

    /* free mem*/

-   free( ack_buf );

-

+   if (ack_buf) free( ack_buf );

    return 0;

-}

-

-

-

-/* append appropriate branch labels for fast reply-transaction matching

-   to outgoing requests

-*/

-int add_branch_label( struct cell *trans, struct sip_msg *p_msg, int branch )

-{

-	char *c;

-

-

-	/* check size now */

-/*

-	if (p_msg->add_to_branch.len+ .... > MAX_BRANCH_PARAM_LEN ) {

-		LOG(L_ERR, "ERROR: add_branch_label: too small branch buffer\n");

-		return -1;

-	}

-*/

-

-	/* check if there already was something else -- if not, allocate */

-

-/*

- = (char*)sh_malloc( MAX_BRANCH_PARAM_LEN );

-

-

-

-	trans->label;

-	trans->hash_index;

-	p_msg->add_to_branch;

-	branch;

-*/

+error:

+   	if (ack_buf) free( ack_buf );

+	return -1;

 }

-

-

-

 /*---------------------------------TIMEOUT HANDLERS--------------------------------------*/

@@ -976,6 +990,20 @@ void delete_handler( void *attr)

        add_to_tail_of_timer_list( hash_table, &(p_cell->dele_tl), DELETE_LIST, DEL_TIME_OUT );

 }

+/* append appropriate branch labels for fast reply-transaction matching

+   to outgoing requests

+*/

+int add_branch_label( struct cell *trans, struct sip_msg *p_msg, int branch )

+{

+	char *c;

+	short n;

-

-

+	n=snprintf( p_msg->add_to_branch_s+p_msg->add_to_branch_len, 

+		  MAX_BRANCH_PARAM_LEN - p_msg->add_to_branch_len,

+		 ".%h.%h.%h",

+		 trans->hash_index, trans->label, branch );

+	if (n==-1) {

+		LOG(L_ERR, "ERROR: add_branch_label: too small branch buffer\n");

+		return -1;

+	} else return 0;

+}

@@ -21,8 +21,12 @@ struct cell;

 #define sh_malloc( size )     malloc(size)

 #define sh_free( ptr )           free(ptr)

+/* already defined in msg_parser.h

 #define get_cseq( p_msg)    ((struct cseq_body*)p_msg->cseq->parsed)

+*/

+/* maximumum length of localy generated acknowledgement */

+#define MAX_ACK_LEN 1024

 int tm_startup();

@@ -670,6 +670,12 @@ error:

 /* parse the headers and adds them to msg->headers and msg->to, from etc.

  * It stops when all the headers requested in flags were parsed, on error

  * (bad header) or end of headers */

+/* note: it continues where it previously stopped and goes ahead until

+   end is encountered or desired HFs are found; if you call it twice

+   for the same HF which is present only once, it will fail the second

+   time; if you want to use a dumbie convenience function which will

+   give you the header you are interested in, look at check_transaction_quadruple

+*/

 int parse_headers(struct sip_msg* msg, int flags)

 {

 	struct hdr_field* hf;

@@ -942,4 +948,16 @@ void free_sip_msg(struct sip_msg* msg)

 }

+/* make sure all HFs needed for transaction identification have been

+   parsed; return 0 if those HFs can't be found

+*/

+int check_transaction_quadruple( struct sip_msg* msg )

+{

+   return 

+   ( (msg->from || (parse_headers( msg, HDR_FROM)!=-1 && msg->from)) &&

+   (msg->to|| (parse_headers( msg, HDR_TO)!=-1 && msg->to)) &&

+   (msg->callid|| (parse_headers( msg, HDR_CALLID)!=-1 && msg->callid)) &&

+   (msg->cseq|| (parse_headers( msg, HDR_CSEQ)!=-1 && msg->cseq)) ) ? 1 : 0;

+

+}

@@ -29,6 +29,9 @@

 #define HDR_ROUTE        256

 #define HDR_OTHER       65536 /*unknown header type*/

+/* maximum length of values appended to Via-branch parameter */

+#define	MAX_BRANCH_PARAM_LEN	32

+

 /* via param types

  * WARNING: keep in sync w/ FIN_*, GEN_PARAM and PARAM_ERROR from via_parse.c*/

 enum{

@@ -37,6 +40,9 @@ enum{

 		PARAM_ERROR

 };

+/* casting macro for accessing CSEQ body */

+#define get_cseq( p_msg)    ((struct cseq_body*)p_msg->cseq->parsed)

+

 #define INVITE_LEN	6

@@ -169,6 +175,9 @@ struct sip_msg{

 	struct lump* repl_add_rm; /* only for localy generated replies !!!*/

 	str add_to_branch; /* whatever whoever want to append to branch comes here */

+	char add_to_branch_s[MAX_BRANCH_PARAM_LEN];

+	short add_to_branch_len;

+

 };

@@ -213,5 +222,7 @@ void clean_hdr_field(struct hdr_field* hf);

 void free_hdr_field_lst(struct hdr_field* hf);

 void free_sip_msg(struct sip_msg* msg);

+int check_transaction_quadruple( struct sip_msg* msg );

+

 #endif

@@ -164,11 +164,7 @@ char * build_req_buf_from_sip_req(struct sip_msg* msg, unsigned int *returned_le

 		/* loop checks ? */

 		if (loop_checks) {

-			if (	(msg->from || (parse_headers( msg, HDR_FROM)!=-1 && msg->from)) &&

-				(msg->to|| (parse_headers( msg, HDR_TO)!=-1 && msg->to)) &&

-				(msg->callid|| (parse_headers( msg, HDR_CALLID)!=-1 && msg->callid)) &&

-				(msg->cseq|| (parse_headers( msg, HDR_CSEQ)!=-1 && msg->cseq)) ) {

-

+			if (check_transaction_quadruple( msg )) {

 				str src[5];

 				int r;

@@ -176,7 +172,7 @@ char * build_req_buf_from_sip_req(struct sip_msg* msg, unsigned int *returned_le

 				src[1]= msg->to->body; 

 				src[2]= msg->callid->body; 

 				src[3]= msg->first_line.u.request.uri; 

-				src[4]= ((struct cseq_body *)(msg->cseq->parsed))->number;

+				src[4]= get_cseq( msg )->number;

 				MDStringArray ( line_buf+via_len-1, src, 5 );

 				DBG("DEBUG: build_req_buf_from_sip_req: branch loop detection: %s, %s, %s, %s, %s -> %s32\n",

@@ -184,6 +180,7 @@ char * build_req_buf_from_sip_req(struct sip_msg* msg, unsigned int *returned_le

 					msg->first_line.u.request.uri.s,

 					((struct cseq_body *)(msg->cseq->parsed))->number.s,

 					line_buf+via_len-1 );

+				DBG("WARNING: build_req_buf_from_sip_req: branch computation NOT over canonical values\n");

 				via_len+=MD5_LEN - 1;

 			} else DBG("DEBUG: build_req_buf_from_sip_req: required HFs for loop checking missing\n");

@@ -64,6 +64,11 @@ int receive_msg(char* buf, unsigned int len, unsigned long src_ip)

 			goto error;

 		}

 		/* check if neccesarry to add receive?->moved to forward_req */

+

+		/* loop checks */

+		if (loop_checks) {

+			DBG("WARNING: receive_msg: Placeholder for loop check. NOT implemented yet.\n");

+		}

 		/* exec routing script */

 		DBG("preparing to run routing scripts...\n");