From 8b8772eed154a4a7c0124fd0591cbcb50d801399 Mon Sep 17 00:00:00 2001
From: Thomas Bernard <miniupnp@free.fr>
Date: Fri, 28 Sep 2012 11:12:50 +0200
Subject: [PATCH] miniupnpd: Support Expect: 100-continue for POST HTTP
 requests

---
 miniupnpd/Changelog.txt |  1 +
 miniupnpd/upnphttp.c    | 67 +++++++++++++++++++++++++++++++++++++++++
 miniupnpd/upnphttp.h    |  7 +++++
 3 files changed, 75 insertions(+)

diff --git a/miniupnpd/Changelog.txt b/miniupnpd/Changelog.txt
index 38cf786..28792b9 100644
--- a/miniupnpd/Changelog.txt
+++ b/miniupnpd/Changelog.txt
@@ -7,6 +7,7 @@ $Id: Changelog.txt,v 1.309 2012/09/27 16:01:10 nanard Exp $
   SetDefaultConnectionService() checks its argumnents in UPNP_STRICT mode
   Support for Accept-Language/Content-Language HTTP headers
   Content-Type is now text/xml; charset="utf-8" to conform with UDA v1.1
+  Support Expect: 100-continue for POST HTTP requests
 
 2012/09/20:
   Cleaning code in ipfw (Jardel Weyrich)
diff --git a/miniupnpd/upnphttp.c b/miniupnpd/upnphttp.c
index 119ed46..248e325 100644
--- a/miniupnpd/upnphttp.c
+++ b/miniupnpd/upnphttp.c
@@ -129,6 +129,19 @@ ParseHttpHeaders(struct upnphttp * h)
 				memcpy(h->accept_language, p, n);
 				h->accept_language[n] = '\0';
 			}
+			else if(strncasecmp(line, "expect", 6) == 0)
+			{
+				p = colon;
+				n = 0;
+				while(*p == ':' || *p == ' ' || *p == '\t')
+					p++;
+				while(p[n]>=' ')
+					n++;
+				if(strncasecmp(p, "100-continue", 12) == 0) {
+					h->respflags |= FLAG_CONTINUE;
+					syslog(LOG_DEBUG, "\"Expect: 100-Continue\" header detected");
+				}
+			}
 #ifdef ENABLE_EVENTS
 			else if(strncasecmp(line, "Callback", 8)==0)
 			{
@@ -281,6 +294,7 @@ ProcessHTTPPOST_upnphttp(struct upnphttp * h)
 {
 	if((h->req_buflen - h->req_contentoff) >= h->req_contentlen)
 	{
+		/* the request body is received */
 		if(h->req_soapActionOff > 0)
 		{
 			/* we can process the request */
@@ -301,6 +315,20 @@ ProcessHTTPPOST_upnphttp(struct upnphttp * h)
 			SendRespAndClose_upnphttp(h);
 		}
 	}
+	else if(h->respflags & FLAG_CONTINUE)
+	{
+		/* Sending the 100 Continue response */
+		if(!h->res_buf) {
+			h->res_buf = malloc(256);
+			h->res_buf_alloclen = 256;
+		}
+		h->res_buflen = snprintf(h->res_buf, h->res_buf_alloclen,
+		                         "%s 100 Continue\r\n\r\n", h->HttpVer);
+		h->res_sent = 0;
+		h->state = ESendingContinue;
+		if(SendResp_upnphttp(h))
+			h->state = EWaitingForHttpContent;
+	}
 	else
 	{
 		/* waiting for remaining data */
@@ -645,6 +673,10 @@ Process_upnphttp(struct upnphttp * h)
 			}
 		}
 		break;
+	case ESendingContinue:
+		if(SendResp_upnphttp(h))
+			h->state = EWaitingForHttpContent;
+		break;
 	case ESendingAndClosing:
 		SendRespAndClose_upnphttp(h);
 		break;
@@ -772,6 +804,41 @@ BuildResp_upnphttp(struct upnphttp * h,
 	BuildResp2_upnphttp(h, 200, "OK", body, bodylen);
 }
 
+int
+SendResp_upnphttp(struct upnphttp * h)
+{
+	ssize_t n;
+
+	while (h->res_sent < h->res_buflen)
+	{
+		n = send(h->socket, h->res_buf + h->res_sent,
+		         h->res_buflen - h->res_sent, 0);
+		if(n<0)
+		{
+			if(errno == EINTR)
+				continue;	/* try again immediatly */
+			if(errno == EAGAIN || errno == EWOULDBLOCK)
+			{
+				/* try again later */
+				return 0;
+			}
+			syslog(LOG_ERR, "send(res_buf): %m");
+			break; /* avoid infinite loop */
+		}
+		else if(n == 0)
+		{
+			syslog(LOG_ERR, "send(res_buf): %d bytes sent (out of %d)",
+							h->res_sent, h->res_buflen);
+			break;
+		}
+		else
+		{
+			h->res_sent += n;
+		}
+	}
+	return 1;	/* finished */
+}
+
 void
 SendRespAndClose_upnphttp(struct upnphttp * h)
 {
diff --git a/miniupnpd/upnphttp.h b/miniupnpd/upnphttp.h
index bb08ecc..434aa31 100644
--- a/miniupnpd/upnphttp.h
+++ b/miniupnpd/upnphttp.h
@@ -34,6 +34,7 @@
 enum httpStates {
 	EWaitingForHttpRequest = 0,
 	EWaitingForHttpContent,
+	ESendingContinue,
 	ESendingAndClosing,
 	EToDelete = 100
 };
@@ -86,6 +87,9 @@ struct upnphttp {
 /* Include the "SID:" header in response */
 #define FLAG_SID		0x02
 
+/* If set, the POST request included a "Expect: 100-continue" header */
+#define FLAG_CONTINUE	0x40
+
 /* If set, the Content-Type is set to text/xml, otherwise it is text/xml */
 #define FLAG_HTML		0x80
 
@@ -131,6 +135,9 @@ BuildResp2_upnphttp(struct upnphttp * h, int respcode,
                     const char * respmsg,
                     const char * body, int bodylen);
 
+int
+SendResp_upnphttp(struct upnphttp *);
+
 /* SendRespAndClose_upnphttp() */
 void
 SendRespAndClose_upnphttp(struct upnphttp *);