new auth

src/cmd/auth/factotum/conv.c

@@ -0,0 +1,254 @@
+#include "std.h"
+#include "dat.h"
+
+Conv *conv;
+
+ulong taggen = 1;
+
+Conv*
+convalloc(char *sysuser)
+{
+	Conv *c;
+
+	c = mallocz(sizeof(Conv), 1);
+	if(c == nil)
+		return nil;
+	c->ref = 1;
+	c->tag = taggen++;
+	c->next = conv;
+	c->sysuser = estrdup(sysuser);
+	c->state = "nascent";
+	c->rpcwait = chancreate(sizeof(void*), 0);
+	c->keywait = chancreate(sizeof(void*), 0);
+	strcpy(c->err, "protocol has not started");
+	conv = c;
+	convreset(c);
+	return c;
+}
+
+void
+convreset(Conv *c)
+{
+	if(c->ref != 1){
+		c->hangup = 1;
+		nbsendp(c->rpcwait, 0);
+		while(c->ref > 1)
+			yield();
+		c->hangup = 0;
+	}
+	c->state = "nascent";
+	c->err[0] = '\0';
+	freeattr(c->attr);
+	c->attr = nil;
+	c->proto = nil;
+	c->rpc.op = 0;
+	c->active = 0;
+	c->done = 0;
+	c->hangup = 0;
+}
+
+void
+convhangup(Conv *c)
+{
+	c->hangup = 1;
+	c->rpc.op = 0;
+	(*c->kickreply)(c);
+	nbsendp(c->rpcwait, 0);
+}
+
+void
+convclose(Conv *c)
+{
+	Conv *p;
+
+	if(c == nil)
+		return;
+
+	if(--c->ref > 0)
+		return;
+
+	if(c == conv){
+		conv = c->next;
+		goto free;
+	}
+	for(p=conv; p && p->next!=c; p=p->next)
+		;
+	if(p == nil){
+		print("cannot find conv in list\n");
+		return;
+	}
+	p->next = c->next;
+
+free:
+	c->next = nil;
+	free(c);
+}
+
+static Rpc*
+convgetrpc(Conv *c, int want)
+{
+	for(;;){
+		if(c->hangup){
+			werrstr("hangup");
+			return nil;
+		}
+		if(c->rpc.op == RpcUnknown){
+			recvp(c->rpcwait);
+			if(c->hangup){
+				werrstr("hangup");
+				return nil;
+			}
+			if(c->rpc.op == RpcUnknown)
+				continue;
+		}
+		if(want < 0 || c->rpc.op == want)
+			return &c->rpc;
+		rpcrespond(c, "phase in state '%s' want '%s'", c->state, rpcname[want]);
+	}
+	return nil;	/* not reached */
+}
+
+/* read until the done function tells us that's enough */
+int
+convreadfn(Conv *c, int (*done)(void*, int), char **ps)
+{
+	int n;
+	Rpc *r;
+	char *s;
+
+	for(;;){
+		r = convgetrpc(c, RpcWrite);
+		if(r == nil)
+			return -1;
+		n = (*done)(r->data, r->count);
+		if(n == r->count)
+			break;
+		rpcrespond(c, "toosmall %d", n);
+	}
+
+	s = emalloc(r->count+1);
+	memmove(s, r->data, r->count);
+	s[r->count] = 0;
+	*ps = s;
+	rpcrespond(c, "ok");
+	return r->count;
+}
+
+/*
+ * read until we get a non-zero write.  assumes remote side
+ * knows something about the protocol (is not auth_proxy).
+ * the remote side typically won't bother with the zero-length
+ * write to find out the length -- the loop is there only so the
+ * test program can call auth_proxy on both sides of a pipe
+ * to play a conversation.
+ */
+int
+convreadm(Conv *c, char **ps)
+{
+	char *s;
+	Rpc *r;
+
+	for(;;){
+		r = convgetrpc(c, RpcWrite);
+		if(r == nil)
+			return -1;
+		if(r->count > 0)
+			break;
+		rpcrespond(c, "toosmall %d", AuthRpcMax);
+	}
+	s = emalloc(r->count+1);
+	memmove(s, r->data, r->count);
+	s[r->count] = 0;
+	*ps = s;
+	rpcrespond(c, "ok");
+	return r->count;
+}
+
+/* read exactly count bytes */
+int
+convread(Conv *c, void *data, int count)
+{
+	Rpc *r;
+
+	for(;;){
+		r = convgetrpc(c, RpcWrite);
+		if(r == nil)
+			return -1;
+		if(r->count == count)
+			break;
+		if(r->count < count)
+			rpcrespond(c, "toosmall %d", count);
+		else
+			rpcrespond(c, "error too much data; want %d got %d", count, r->count);
+	}
+	memmove(data, r->data, count);
+	rpcrespond(c, "ok");
+	return 0;
+}
+
+/* write exactly count bytes */
+int
+convwrite(Conv *c, void *data, int count)
+{
+	Rpc *r;
+
+	for(;;){
+		r = convgetrpc(c, RpcRead);
+		if(r == nil)
+			return -1;
+		break;
+	}
+	rpcrespondn(c, "ok", data, count);
+	return 0;
+}
+
+/* print to the conversation */
+int
+convprint(Conv *c, char *fmt, ...)
+{
+	char *s;
+	va_list arg;
+	int ret;
+
+	va_start(arg, fmt);
+	s = vsmprint(fmt, arg);
+	va_end(arg);
+	if(s == nil)
+		return -1;
+	ret = convwrite(c, s, strlen(s));
+	free(s);
+	return ret;
+}
+
+/* ask for a key */
+int
+convneedkey(Conv *c, Attr *a)
+{
+	/*
+	 * Piggyback key requests in the usual RPC channel.
+	 * Wait for the next RPC and then send a key request
+	 * in response.  The keys get added out-of-band (via the
+	 * ctl file), so assume the key has been added when the
+	 * next request comes in.
+	 */
+	if(convgetrpc(c, -1) == nil)
+		return -1;
+	rpcrespond(c, "needkey %A", a);
+	if(convgetrpc(c, -1) == nil)
+		return -1;
+	return 0;
+}
+
+/* ask for a replacement for a bad key*/
+int
+convbadkey(Conv *c, Key *k, char *msg, Attr *a)
+{
+	if(convgetrpc(c, -1) == nil)
+		return -1;
+	rpcrespond(c, "badkey %A %N\n%s\n%A",
+		k->attr, k->privattr, msg, a);
+	if(convgetrpc(c, -1) == nil)
+		return -1;
+	return 0;
+}
+