merge -r62831:64079 branches/maintenance to release

1 files changed, 193 insertions, 0 deletions

diff --git a/indra/newview/llsrv.cpp b/indra/newview/llsrv.cpp
new file mode 100644
index 0000000000..cd05d9c107
--- /dev/null
+++ b/indra/newview/llsrv.cpp
@@ -0,0 +1,193 @@
+/** 
+ * @file llsrv.cpp
+ * @brief Wrapper for DNS SRV record lookups
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+#include "llviewerprecompiledheaders.h"
+
+#include "llsrv.h"
+
+using namespace std;
+
+#if LL_WINDOWS
+
+#undef UNICODE
+#include <winsock2.h>
+#include <windns.h>
+
+vector<LLSRVRecord> LLSRV::query(const string& name)
+{
+	vector<LLSRVRecord> recs;
+	DNS_RECORD *rec;
+	DNS_STATUS status;
+
+	status = DnsQuery(name.c_str(), DNS_TYPE_SRV, DNS_QUERY_STANDARD, NULL, &rec, NULL);
+	if (!status)
+	{
+		for (DNS_RECORD *cur = rec; cur != NULL; cur = cur->pNext)
+		{
+			if (cur->wType != DNS_TYPE_SRV)
+			{
+				continue;
+			}
+			recs.push_back(LLSRVRecord(cur->Data.Srv.wPriority,
+									   cur->Data.Srv.wWeight,
+									   cur->Data.Srv.pNameTarget,
+									   cur->Data.Srv.wPort));
+		}
+		DnsRecordListFree(rec, DnsFreeRecordListDeep);
+	}
+
+	return recs;
+}
+
+#else // !LL_WINDOWS
+
+#include <netinet/in.h>
+#include <arpa/nameser.h>
+#include <arpa/nameser_compat.h>
+#include <resolv.h>
+
+#include <netdb.h>
+
+vector<LLSRVRecord> LLSRV::query(const string& queryName)
+{
+	unsigned char response[16384];
+	vector<LLSRVRecord> recs;
+	char name[1024];
+	int len;
+	
+	len = res_query(queryName.c_str(), ns_c_in, ns_t_srv, response,
+					sizeof(response));
+
+	if (len == -1)
+	{
+		llinfos << "Query failed for " << queryName << llendl;
+		return recs;
+	}
+	else if (len > (int) sizeof(response))
+	{
+		llinfos << "Response too big for " << queryName
+				<< " (capacity " << sizeof(response)
+				<< ", response " << len << ")" << llendl;
+		return recs;
+	}
+
+    // We "should" be using libresolv's ns_initparse and ns_parserr to
+    // parse the result of our query.  However, libresolv isn't
+    // packaged correctly on Linux (as of BIND 9), so neither of these
+    // functions is available without statically linking against
+    // libresolv.  Ugh!  So we parse the response ourselves.
+
+	const unsigned char *pos = response + sizeof(HEADER);
+	const unsigned char *end = response + len;
+	const HEADER *hdr = (const HEADER *) response;
+
+	// Skip over the query embedded in the response.
+
+	for (int q = ntohs(hdr->qdcount); q > 0; --q)
+	{
+		len = dn_expand(response, end, pos, name, sizeof(name));
+
+		if (len == -1)
+		{
+			llinfos << "Could not expand queried name in RR response" << llendl;
+			return recs;
+		}
+		
+		pos += len + NS_QFIXEDSZ;
+	}
+	
+	for (int a = ntohs(hdr->ancount); a > 0; --a)
+	{
+		static const ns_rr *rr;
+
+		len = dn_expand(response, end, pos, name, sizeof(name) - 1);
+		if (len == -1)
+		{
+			llinfos << "Could not expand response name in RR response" << llendl;
+			return recs;
+		}
+
+		// Skip over the resource name and headers we don't care about.
+
+		pos += len + sizeof(rr->type) + sizeof(rr->rr_class) +
+			sizeof(rr->ttl) + sizeof(rr->rdlength);
+		
+		U16 prio;
+		U16 weight;
+		U16 port;
+
+		NS_GET16(prio, pos);
+		NS_GET16(weight, pos);
+		NS_GET16(port, pos);
+		
+		len = dn_expand(response, end, pos, name, sizeof(name) - 1);
+
+		if (len == -1)
+		{
+			llinfos << "Could not expand name in RR response" << llendl;
+			return recs;
+		}
+
+		recs.push_back(LLSRVRecord(prio, weight, name, port));
+	}
+
+	// There are likely to be more records in the response, but we
+	// don't care about those, at least for now.
+
+	return recs;
+}
+
+#endif // LL_WINDOWS
+
+vector<string> LLSRV::rewriteURI(const string& uriStr)
+{
+	LLURI uri(uriStr);
+	const string& scheme = uri.scheme();
+	llinfos << "Rewriting " << uriStr << llendl;
+	string serviceName("_" + scheme + "._tcp." + uri.hostName());
+	llinfos << "Querying for " << serviceName << llendl;
+	vector<LLSRVRecord> srvs(LLSRV::query(serviceName));
+	vector<string> rewritten;
+
+	if (srvs.empty())
+	{
+		llinfos << "No query results; using " << uriStr << llendl;
+		rewritten.push_back(uriStr);
+	}
+	else
+	{
+		vector<LLSRVRecord>::const_iterator iter;
+		size_t maxSrvs = 3;
+		size_t i;
+
+		llinfos << "Got " << srvs.size() << " results" << llendl;
+		if (srvs.size() > maxSrvs)
+		{
+			llinfos << "Clamping to " << maxSrvs << llendl;
+		}
+
+		for (iter = srvs.begin(), i = 0;
+			 iter != srvs.end() && i < maxSrvs; ++iter, ++i)
+		{
+			LLURI newUri(scheme,
+						 uri.userName(),
+						 uri.password(),
+						 iter->target(),
+						 uri.defaultPort() ? iter->port() : uri.hostPort(),
+						 uri.escapedPath(),
+						 uri.escapedQuery());
+			string newUriStr(newUri.asString());
+
+			llinfos << "Rewrite[" << i << "] " << newUriStr << llendl;
+
+			rewritten.push_back(newUriStr);
+		}
+	}
+
+	return rewritten;
+}