layed out initial structures. began work on registration procedure.

1 files changed, 211 insertions, 0 deletions

diff --git a/sip.c b/sip.c
new file mode 100644
index 0000000..267c49a
--- /dev/null
+++ b/sip.c
@@ -0,0 +1,211 @@
+#include <u.h>
+#include <libc.h>
+#include <bio.h>
+#include <draw.h>
+#include "dat.h"
+#include "fns.h"
+
+static char sipversion[] = "SIP/2.0";
+static char *methodstrtab[] = {
+ [REGISTER]	"REGISTER",
+ [INVITE]	"INVITE",
+ [ACK]		"ACK",
+ [BYE]		"BYE",
+ [CANCEL]	"CANCEL",
+ [OPTIONS]	"OPTIONS",
+ [NOTIFY]	"NOTIFY",
+ [SUBSCRIBE]	"SUBSCRIBE",
+ [INFO]		"INFO",
+ [MESSAGE]	"MESSAGE",
+ [UPDATE]	"UPDATE",
+ [REFER]	"REFER",
+};
+
+static char registerhdr0[] = "REGISTER sip:%s %s\r\n"
+	"Via: %s/UDP %s:%s;branch=z9hG4bK703d971c0c737b8e;rport\r\n"
+	"Contact: <sip:%s-0x82a66a010@%s:%s>;expires=3849\r\n"
+	"Max-Forwards: 70\r\n"
+	"To: <sip:%s@%s>\r\n"
+	"From: <sip:%s@%s>;tag=4a5a693256d38cbc\r\n"
+	"Call-ID: 2cee372fc4be4e45\r\n"
+	"CSeq: 16021 REGISTER\r\n"
+	"User-Agent: catphone (plan9front)\r\n"
+	"Allow: INVITE,ACK,BYE,CANCEL,OPTIONS,NOTIFY,SUBSCRIBE,INFO,MESSAGE,UPDATE,REFER\r\n"
+	"Content-Length: 0\r\n"
+	"\r\n";
+static char registerhdr[] = "REGISTER sip:10.0.0.104 SIP/2.0\r\n"
+	"Via: SIP/2.0/UDP 10.0.1.9:54022;branch=z9hG4bKdf800c31b9a88ffb;rport\r\n"
+	"Contact: <sip:sam-0x82a66a010@10.0.1.9:54022>;expires=3849\r\n"
+	"Max-Forwards: 70\r\n"
+	"Authorization: Digest username=\"sam\", realm=\"asterisk\", nonce=\"0d39ab10\", uri=\"sip:10.0.0.104\", response=\"a12e05b52604b5226763ce577d5c240b\", algorithm=MD5\r\n"
+	"To: <sip:sam@10.0.0.104>\r\n"
+	"From: <sip:sam@10.0.0.104>;tag=4a5a693256d38cbc\r\n"
+	"Call-ID: 2cee372fc4be4e45\r\n"
+	"CSeq: 16022 REGISTER\r\n"
+	"User-Agent: catphone (plan9front)\r\n"
+	"Allow: INVITE,ACK,BYE,CANCEL,OPTIONS,NOTIFY,SUBSCRIBE,INFO,MESSAGE,UPDATE,REFER\r\n"
+	"Content-Length: 0\r\n"
+	"\r\n";
+
+static char *
+getmethodstr(SipMethod m)
+{
+	return methodstrtab[m];
+}
+
+static uint
+hash(char *s)
+{
+	uint h;
+
+	h = 0x811c9dc5;
+	while(*s != 0)
+		h = (h^(uchar)*s++) * 0x1000193;
+	return h % 13;
+}
+
+void
+addheader(Hdrtab *ht, char *name, char *value)
+{
+	Hdr *h, *newh;
+	uint key;
+
+	key = hash(name);
+	newh = emalloc(sizeof(Hdr));
+	newh->name = strdup(name);
+	newh->value = strdup(value);
+	newh->next = nil;
+
+	h = ht->headers[key];
+	if(h == nil){
+		ht->headers[key] = newh;
+		return;
+	}
+	while(h->next != nil)
+		h = h->next;
+	h->next = newh;
+}
+
+Hdr *
+getheader(Hdrtab *ht, char *name)
+{
+	Hdr *h;
+	uint key;
+
+	key = hash(name);
+	for(h = ht->headers[key]; h != nil; h = h->next)
+		if(cistrcmp(h->name, name) == 0)
+			return h;
+	return nil;
+}
+
+void
+delheader(Hdrtab *ht, char *name)
+{
+	Hdr **h, *nh;
+	uint key;
+
+	key = hash(name);
+	h = &ht->headers[key];
+	while(*h != nil){
+		nh = (*h)->next;
+		if(cistrcmp((*h)->name, name) == 0){
+			free((*h)->name);
+			free((*h)->value);
+			free(*h);
+		}
+		*h = nh;
+	}
+}
+
+void
+delheaders(Hdrtab *ht)
+{
+	Hdr *h, *nh;
+	int i;
+
+	for(i = 0; i < nelem(ht->headers); i++)
+		for(h = ht->headers[i]; h != nil; h = nh){
+			nh = h->next;
+			free(h->name);
+			free(h->value);
+			free(h);
+		}
+}
+
+/* rfc3261 § 10 - Registrations */
+static int
+sip_register(Sip *s, char *user, char *pass)
+{
+	Biobuf *bin, *bout;
+	char *line, *p, *kv[2];
+	int n;
+
+	if((bin = Bfdopen(s->fd, OREAD)) == nil)
+		sysfatal("Bfdopen: %r");
+	if((bout = Bfdopen(s->fd, OWRITE)) == nil)
+		sysfatal("Bfdopen: %r");
+
+	/* present yourself */
+	Bprint(bout, registerhdr0, s->nci->rsys, sipversion,
+		sipversion, s->nci->lsys, s->nci->lserv,
+		user, s->nci->lsys, s->nci->lserv,
+		user, s->nci->rsys,
+		user, s->nci->rsys);
+	Bflush(bout);
+
+	/* wait for the challenge */
+	while((line = Brdline(bin, '\n')) != nil){
+		if(strncmp(line, "\r\n", 2) == 0)
+			break;
+
+		p = strchr(line, '\r');
+		*p++ = 0, *p = 0;
+		if(debug)
+			fprint(2, "%s\n", line);
+
+		if(strstr(line, ":") == nil)
+			continue;
+
+		gettokens(line, kv, nelem(kv), ": ");
+		if(debug)
+			fprint(2, "got key=%s value=%s\n", kv[0], kv[1]);
+	}
+
+	/* respond to the challenge */
+
+	/* get the OK */
+
+	Bterm(bin);
+	Bterm(bout);
+
+	return 0;
+}
+
+Sip *
+mksip(int fd)
+{
+	Sip *s;
+
+	s = emalloc(sizeof(Sip));
+	memset(s, 0, sizeof *s);
+	s->version = 2;
+	s->nci = getnetconninfo(nil, fd);
+	if(s->nci == nil){
+		werrstr("couldn't getnetconninfo");
+		free(s);
+		return nil;
+	}
+	s->fd = fd;
+	s->reg = sip_register;
+
+	return s;
+}
+
+void
+rmsip(Sip *s)
+{
+	close(s->fd);
+	freenetconninfo(s->nci);
+	free(s);
+}