Fixed StreamID and Smoother name swapping for big endian machines (#644)

* Fixed big-endian swapping for little-endian transport
Haivision · Apr 29, 2019 · 7c19251 · 7c19251
1 parent c05ca7d
commit 7c19251
Show file tree

Hide file tree

Showing 2 changed files with 149 additions and 12 deletions.
diff --git a/srtcore/core.cpp b/srtcore/core.cpp
@@ -1778,6 +1778,8 @@ bool CUDT::createSrtHandshake(ref_t<CPacket> r_pkt, ref_t<CHandShake> r_hs,
 
         memset(p+offset, 0, aligned_bytesize);
         memcpy(p+offset, m_sStreamName.data(), m_sStreamName.size());
+        // Preswap to little endian (in place due to possible padding zeros)
+        HtoILA((uint32_t*)(p+offset), (uint32_t*)(p+offset), wordsize);
 
         ra_size = wordsize;
         *pcmdspec = HS_CMDSPEC_CMD::wrap(SRT_CMD_SID) | HS_CMDSPEC_SIZE::wrap(ra_size);
@@ -1805,7 +1807,10 @@ bool CUDT::createSrtHandshake(ref_t<CPacket> r_pkt, ref_t<CHandShake> r_hs,
         size_t aligned_bytesize = wordsize*4;
 
         memset(p+offset, 0, aligned_bytesize);
+
         memcpy(p+offset, sm.data(), sm.size());
+        // Preswap to little endian (in place due to possible padding zeros)
+        HtoILA((uint32_t*)(p+offset), (uint32_t*)(p+offset), wordsize);
 
         ra_size = wordsize;
         *pcmdspec = HS_CMDSPEC_CMD::wrap(SRT_CMD_SMOOTHER) | HS_CMDSPEC_SIZE::wrap(ra_size);
@@ -2622,6 +2627,10 @@ bool CUDT::interpretSrtHandshake(const CHandShake& hs, const CPacket& hspkt, uin
                 char target[MAX_SID_LENGTH+1];
                 memset(target, 0, MAX_SID_LENGTH+1);
                 memcpy(target, begin+1, bytelen);
+
+                // Un-swap on big endian machines
+                ItoHLA((uint32_t*)target, (uint32_t*)target, bytelen/sizeof(uint32_t));
+
                 m_sStreamName = target;
                 HLOGC(mglog.Debug, log << "CONNECTOR'S REQUESTED SID [" << m_sStreamName << "] (bytelen=" << bytelen << " blocklen=" << blocklen << ")");
             }
@@ -2638,6 +2647,9 @@ bool CUDT::interpretSrtHandshake(const CHandShake& hs, const CPacket& hspkt, uin
                 char target[MAX_SID_LENGTH+1];
                 memset(target, 0, MAX_SID_LENGTH+1);
                 memcpy(target, begin+1, bytelen);
+                // Un-swap on big endian machines
+                ItoHLA((uint32_t*)target, (uint32_t*)target, bytelen/sizeof(uint32_t));
+
                 string sm = target;
 
                 // As the smoother has been declared by the peer,

diff --git a/srtcore/utilities.h b/srtcore/utilities.h
@@ -76,6 +76,143 @@ written by
 
 // -------------- UTILITIES ------------------------
 
+// --- ENDIAN ---
+// Copied from: https://gist.github.com/panzi/6856583
+// License: Public Domain.
+
+#if (defined(_WIN16) || defined(_WIN32) || defined(_WIN64)) && !defined(__WINDOWS__)
+
+#	define __WINDOWS__
+
+#endif
+
+#if defined(__linux__) || defined(__CYGWIN__)
+
+#	include <endian.h>
+
+#elif defined(__APPLE__)
+
+#	include <libkern/OSByteOrder.h>
+
+#	define htobe16(x) OSSwapHostToBigInt16(x)
+#	define htole16(x) OSSwapHostToLittleInt16(x)
+#	define be16toh(x) OSSwapBigToHostInt16(x)
+#	define le16toh(x) OSSwapLittleToHostInt16(x)
+
+#	define htobe32(x) OSSwapHostToBigInt32(x)
+#	define htole32(x) OSSwapHostToLittleInt32(x)
+#	define be32toh(x) OSSwapBigToHostInt32(x)
+#	define le32toh(x) OSSwapLittleToHostInt32(x)
+
+#	define htobe64(x) OSSwapHostToBigInt64(x)
+#	define htole64(x) OSSwapHostToLittleInt64(x)
+#	define be64toh(x) OSSwapBigToHostInt64(x)
+#	define le64toh(x) OSSwapLittleToHostInt64(x)
+
+#	define __BYTE_ORDER    BYTE_ORDER
+#	define __BIG_ENDIAN    BIG_ENDIAN
+#	define __LITTLE_ENDIAN LITTLE_ENDIAN
+#	define __PDP_ENDIAN    PDP_ENDIAN
+
+#elif defined(__OpenBSD__)
+
+#	include <sys/endian.h>
+
+#elif defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
+
+#	include <sys/endian.h>
+
+#	define be16toh(x) betoh16(x)
+#	define le16toh(x) letoh16(x)
+
+#	define be32toh(x) betoh32(x)
+#	define le32toh(x) letoh32(x)
+
+#	define be64toh(x) betoh64(x)
+#	define le64toh(x) letoh64(x)
+
+#elif defined(__WINDOWS__)
+
+#	include <winsock2.h>
+
+#	if BYTE_ORDER == LITTLE_ENDIAN
+
+#		define htobe16(x) htons(x)
+#		define htole16(x) (x)
+#		define be16toh(x) ntohs(x)
+#		define le16toh(x) (x)
+
+#		define htobe32(x) htonl(x)
+#		define htole32(x) (x)
+#		define be32toh(x) ntohl(x)
+#		define le32toh(x) (x)
+
+#		define htobe64(x) htonll(x)
+#		define htole64(x) (x)
+#		define be64toh(x) ntohll(x)
+#		define le64toh(x) (x)
+
+#	elif BYTE_ORDER == BIG_ENDIAN
+
+		/* that would be xbox 360 */
+#		define htobe16(x) (x)
+#		define htole16(x) __builtin_bswap16(x)
+#		define be16toh(x) (x)
+#		define le16toh(x) __builtin_bswap16(x)
+
+#		define htobe32(x) (x)
+#		define htole32(x) __builtin_bswap32(x)
+#		define be32toh(x) (x)
+#		define le32toh(x) __builtin_bswap32(x)
+
+#		define htobe64(x) (x)
+#		define htole64(x) __builtin_bswap64(x)
+#		define be64toh(x) (x)
+#		define le64toh(x) __builtin_bswap64(x)
+
+#	else
+
+#		error byte order not supported
+
+#	endif
+
+#	define __BYTE_ORDER    BYTE_ORDER
+#	define __BIG_ENDIAN    BIG_ENDIAN
+#	define __LITTLE_ENDIAN LITTLE_ENDIAN
+#	define __PDP_ENDIAN    PDP_ENDIAN
+
+#else
+
+#	error Endian: platform not supported
+
+#endif
+
+// Hardware <--> Network (big endian) convention
+inline void HtoNLA(uint32_t* dst, const uint32_t* src, size_t size)
+{
+    for (size_t i = 0; i < size; ++ i)
+        dst[i] = htonl(src[i]);
+}
+
+inline void NtoHLA(uint32_t* dst, const uint32_t* src, size_t size)
+{
+    for (size_t i = 0; i < size; ++ i)
+        dst[i] = ntohl(src[i]);
+}
+
+// Hardware <--> Intel (little endian) convention
+inline void HtoILA(uint32_t* dst, const uint32_t* src, size_t size)
+{
+    for (size_t i = 0; i < size; ++ i)
+        dst[i] = htole32(src[i]);
+}
+
+inline void ItoHLA(uint32_t* dst, const uint32_t* src, size_t size)
+{
+    for (size_t i = 0; i < size; ++ i)
+        dst[i] = le32toh(src[i]);
+}
+
 // Bit numbering utility.
 //
 // This is something that allows you to turn 32-bit integers into bit fields.
@@ -233,18 +370,6 @@ inline bool IsSet(int32_t bitset, int32_t flagset)
     return (bitset & flagset) == flagset;
 }
 
-inline void HtoNLA(uint32_t* dst, const uint32_t* src, size_t size)
-{
-    for (size_t i = 0; i < size; ++ i)
-        dst[i] = htonl(src[i]);
-}
-
-inline void NtoHLA(uint32_t* dst, const uint32_t* src, size_t size)
-{
-    for (size_t i = 0; i < size; ++ i)
-        dst[i] = ntohl(src[i]);
-}
-
 // Homecooked version of ref_t. It's a copy of std::reference_wrapper
 // voided of unwanted properties and renamed to ref_t.