Re #1943: AES-GCM crypto support for SRTP

Special thanks to Alexander Traud for the patch.



git-svn-id: http://svn.pjsip.org/repos/pjproject/trunk@5412 74dad513-b988-da41-8d7b-12977e46ad98

7 files changed, 141 insertions, 26 deletions

diff --git a/aconfigure b/aconfigure
index 23c8386d..d82fc108 100755
--- a/aconfigure
+++ b/aconfigure
@@ -640,6 +640,7 @@ ac_no_opencore_amrnb
 libcrypto_present
 libssl_present
 openssl_h_present
+ac_ssl_has_aes_gcm
 ac_no_ssl
 ac_webrtc_ldflags
 ac_webrtc_cflags
@@ -7837,6 +7838,8 @@ if test "x$ac_cross_compile" != "x" -a "x$with_ssl" = "xno"; then
 fi
 
 
+ac_ssl_has_aes_gcm=0
+
 # Check whether --enable-ssl was given.
 if test "${enable_ssl+set}" = set; then :
   enableval=$enable_ssl;
@@ -7948,6 +7951,17 @@ fi
 		if test "x$openssl_h_present" = "x1" -a "x$libssl_present" = "x1" -a "x$libcrypto_present" = "x1"; then
 	        	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: OpenSSL library found, SSL support enabled" >&5
 $as_echo "OpenSSL library found, SSL support enabled" >&6; }
+
+			# Check if SRTP should be compiled with OpenSSL
+			# support, to enable cryptos such as AES GCM	AC_CHECK_LIB(crypto,EVP_aes_128_gcm,[ac_ssl_has_aes_gcm=1])
+			if test "x$ac_ssl_has_aes_gcm" = "x1"; then
+				{ $as_echo "$as_me:${as_lineno-$LINENO}: result: OpenSSL has AES GCM support, SRTP will use OpenSSl version" >&5
+$as_echo "OpenSSL has AES GCM support, SRTP will use OpenSSl version" >&6; }
+			else
+				{ $as_echo "$as_me:${as_lineno-$LINENO}: result: OpenSSL AES GCM support not found, SRTP will only support AES CM cryptos" >&5
+$as_echo "OpenSSL AES GCM support not found, SRTP will only support AES CM cryptos" >&6; }
+			fi
+
 			# PJSIP_HAS_TLS_TRANSPORT setting follows PJ_HAS_SSL_SOCK
 			#AC_DEFINE(PJSIP_HAS_TLS_TRANSPORT, 1)
 			$as_echo "#define PJ_HAS_SSL_SOCK 1" >>confdefs.h
diff --git a/aconfigure.ac b/aconfigure.ac
index 4ea4d498..795c6e4e 100644
--- a/aconfigure.ac
+++ b/aconfigure.ac
@@ -1575,6 +1575,7 @@ fi
 
 dnl # Include SSL support
 AC_SUBST(ac_no_ssl)
+AC_SUBST(ac_ssl_has_aes_gcm,0)
 AC_ARG_ENABLE(ssl,
 	      AS_HELP_STRING([--disable-ssl],
 			     [Exclude SSL support the build (default: autodetect)])
@@ -1600,6 +1601,15 @@ AC_ARG_ENABLE(ssl,
 		AC_CHECK_LIB(ssl,SSL_library_init,[libssl_present=1 && LIBS="-lssl $LIBS"])
 		if test "x$openssl_h_present" = "x1" -a "x$libssl_present" = "x1" -a "x$libcrypto_present" = "x1"; then
 	        	AC_MSG_RESULT([OpenSSL library found, SSL support enabled])
+			
+			# Check if SRTP should be compiled with OpenSSL
+			# support, to enable cryptos such as AES GCM	AC_CHECK_LIB(crypto,EVP_aes_128_gcm,[ac_ssl_has_aes_gcm=1])
+			if test "x$ac_ssl_has_aes_gcm" = "x1"; then
+				AC_MSG_RESULT([OpenSSL has AES GCM support, SRTP will use OpenSSl version])
+			else
+				AC_MSG_RESULT([OpenSSL AES GCM support not found, SRTP will only support AES CM cryptos])
+			fi
+
 			# PJSIP_HAS_TLS_TRANSPORT setting follows PJ_HAS_SSL_SOCK
 			#AC_DEFINE(PJSIP_HAS_TLS_TRANSPORT, 1)
 			AC_DEFINE(PJ_HAS_SSL_SOCK, 1)
diff --git a/pjmedia/include/pjmedia/config.h b/pjmedia/include/pjmedia/config.h
index cbcd08fb..a173af42 100644
--- a/pjmedia/include/pjmedia/config.h
+++ b/pjmedia/include/pjmedia/config.h
@@ -953,6 +953,61 @@
 
 
 /**
+ * Maximum number of SRTP cryptos.
+ *
+ * Default: 16
+ */
+#ifndef PJMEDIA_SRTP_MAX_CRYPTOS
+#   define PJMEDIA_SRTP_MAX_CRYPTOS		    16
+#endif
+
+
+/**
+ * Enable AES_CM_256 cryptos in SRTP.
+ * Default: enabled.
+ */
+#ifndef PJMEDIA_SRTP_HAS_AES_CM_256
+#   define PJMEDIA_SRTP_HAS_AES_CM_256	    	    1
+#endif
+
+
+/**
+ * Enable AES_CM_192 cryptos in SRTP
+ * Default: disabled.
+ */
+#ifndef PJMEDIA_SRTP_HAS_AES_CM_192
+#   define PJMEDIA_SRTP_HAS_AES_CM_192	    	    0
+#endif
+
+
+/**
+ * Enable AES_CM_128 cryptos in SRTP.
+ * Default: enabled.
+ */
+#ifndef PJMEDIA_SRTP_HAS_AES_CM_128
+#   define PJMEDIA_SRTP_HAS_AES_CM_128    	    1
+#endif
+
+
+/**
+ * Enable AES_GCM_256 cryptos in SRTP.
+ * Default: disabled.
+ */
+#ifndef PJMEDIA_SRTP_HAS_AES_GCM_256
+#   define PJMEDIA_SRTP_HAS_AES_GCM_256	    	    0
+#endif
+
+
+/**
+ * Enable AES_GCM_128 cryptos in SRTP.
+ * Default: disabled.
+ */
+#ifndef PJMEDIA_SRTP_HAS_AES_GCM_128
+#   define PJMEDIA_SRTP_HAS_AES_GCM_128    	    0
+#endif
+
+
+/**
  * Let the library handle libsrtp initialization and deinitialization.
  * Application may want to disable this and manually perform libsrtp
  * initialization and deinitialization when it needs to use libsrtp
diff --git a/pjmedia/include/pjmedia/transport_srtp.h b/pjmedia/include/pjmedia/transport_srtp.h
index 910ec1d0..fe5337ac 100644
--- a/pjmedia/include/pjmedia/transport_srtp.h
+++ b/pjmedia/include/pjmedia/transport_srtp.h
@@ -155,7 +155,7 @@ typedef struct pjmedia_srtp_setting
     /**
      * Specify individual crypto suite setting.
      */
-    pjmedia_srtp_crypto		crypto[8];
+    pjmedia_srtp_crypto		crypto[PJMEDIA_SRTP_MAX_CRYPTOS];
 
 } pjmedia_srtp_setting;
 
diff --git a/pjmedia/src/pjmedia/transport_srtp.c b/pjmedia/src/pjmedia/transport_srtp.c
index c262f070..304d0a6f 100644
--- a/pjmedia/src/pjmedia/transport_srtp.c
+++ b/pjmedia/src/pjmedia/transport_srtp.c
@@ -84,35 +84,56 @@ typedef struct crypto_suite
     sec_serv_t		 service;
 } crypto_suite;
 
-/* Crypto suites as defined on RFC 4568 */
+/* https://www.iana.org/assignments/sdp-security-descriptions/sdp-security-descriptions.xhtml */
 static crypto_suite crypto_suites[] = {
     /* plain RTP/RTCP (no cipher & no auth) */
     {"NULL", NULL_CIPHER, 0, NULL_AUTH, 0, 0, 0, sec_serv_none},
-
+#if defined(PJMEDIA_SRTP_HAS_AES_GCM_256) && \
+    (PJMEDIA_SRTP_HAS_AES_GCM_256 != 0)
+    /* cipher AES_GCM, NULL auth, auth tag len = 16 octets */
+    {"AEAD_AES_256_GCM", AES_256_GCM, AES_256_GCM_KEYSIZE_WSALT,
+	NULL_AUTH, 0, 16, 16, sec_serv_conf_and_auth},
+    /* cipher AES_GCM, NULL auth, auth tag len = 8 octets */
+    {"AEAD_AES_256_GCM_8", AES_256_GCM, AES_256_GCM_KEYSIZE_WSALT,
+	NULL_AUTH, 0, 8, 8, sec_serv_conf_and_auth},
+#endif
+#if defined(PJMEDIA_SRTP_HAS_AES_CM_256) && \
+    (PJMEDIA_SRTP_HAS_AES_CM_256 != 0)
     /* cipher AES_CM_256, auth HMAC_SHA1, auth tag len = 10 octets */
     {"AES_256_CM_HMAC_SHA1_80", AES_ICM, 46, HMAC_SHA1, 20, 10, 10,
 	sec_serv_conf_and_auth},
-
     /* cipher AES_CM_256, auth HMAC_SHA1, auth tag len = 10 octets */
     {"AES_256_CM_HMAC_SHA1_32", AES_ICM, 46, HMAC_SHA1, 20, 4, 10,
-        sec_serv_conf_and_auth},
-
-    /* cipher AES_192_CM, auth HMAC_SHA1, auth tag len = 10 octets */
-    //{"AES_192_CM_HMAC_SHA1_80", AES_ICM, 38, HMAC_SHA1, 20, 10, 10,
-	//sec_serv_conf_and_auth},
-
-    /* cipher AES_192_CM, auth HMAC_SHA1, auth tag len = 4 octets */
-    //{"AES_192_CM_HMAC_SHA1_32", AES_ICM, 38, HMAC_SHA1, 20, 4, 10,
-	//sec_serv_conf_and_auth},
-
-    /* cipher AES_CM, auth HMAC_SHA1, auth tag len = 10 octets */
-    {"AES_CM_128_HMAC_SHA1_80", AES_128_ICM, 30, HMAC_SHA1, 20, 10, 10,
 	sec_serv_conf_and_auth},
-
-    /* cipher AES_CM, auth HMAC_SHA1, auth tag len = 4 octets */
-    {"AES_CM_128_HMAC_SHA1_32", AES_128_ICM, 30, HMAC_SHA1, 20, 4, 10,
+#endif
+#if defined(PJMEDIA_SRTP_HAS_AES_CM_192) && \
+    (PJMEDIA_SRTP_HAS_AES_CM_192 != 0)
+    /* cipher AES_CM_192, auth HMAC_SHA1, auth tag len = 10 octets */
+    {"AES_192_CM_HMAC_SHA1_80", AES_ICM, 38, HMAC_SHA1, 20, 10, 10,
 	sec_serv_conf_and_auth},
-
+    /* cipher AES_CM_192, auth HMAC_SHA1, auth tag len = 4 octets */
+    {"AES_192_CM_HMAC_SHA1_32", AES_ICM, 38, HMAC_SHA1, 20, 4, 10,
+	sec_serv_conf_and_auth},
+#endif
+#if defined(PJMEDIA_SRTP_HAS_AES_GCM_128) && \
+    (PJMEDIA_SRTP_HAS_AES_GCM_128 != 0)
+    /* cipher AES_GCM, NULL auth, auth tag len = 16 octets */
+    {"AEAD_AES_128_GCM", AES_128_GCM, AES_128_GCM_KEYSIZE_WSALT,
+	NULL_AUTH, 0, 16, 16, sec_serv_conf_and_auth},
+
+    /* cipher AES_GCM, NULL auth, auth tag len = 8 octets */
+    {"AEAD_AES_128_GCM_8", AES_128_GCM, AES_128_GCM_KEYSIZE_WSALT,
+	NULL_AUTH, 0, 8, 8, sec_serv_conf_and_auth},
+#endif
+#if defined(PJMEDIA_SRTP_HAS_AES_CM_128) && \
+    (PJMEDIA_SRTP_HAS_AES_CM_128 != 0)
+    /* cipher AES_CM_128, auth HMAC_SHA1, auth tag len = 10 octets */
+    {"AES_CM_128_HMAC_SHA1_80", AES_ICM, 30, HMAC_SHA1, 20, 10, 10,
+	sec_serv_conf_and_auth},
+    /* cipher AES_CM_128, auth HMAC_SHA1, auth tag len = 4 octets */
+    {"AES_CM_128_HMAC_SHA1_32", AES_ICM, 30, HMAC_SHA1, 20, 4, 10,
+	sec_serv_conf_and_auth},
+#endif
     /*
      * F8_128_HMAC_SHA1_8 not supported by libsrtp?
      * {"F8_128_HMAC_SHA1_8", NULL_CIPHER, 0, NULL_AUTH, 0, 0, 0, sec_serv_none}
diff --git a/third_party/build/os-auto.mak.in b/third_party/build/os-auto.mak.in
index ef261f65..66653fa1 100644
--- a/third_party/build/os-auto.mak.in
+++ b/third_party/build/os-auto.mak.in
@@ -35,6 +35,22 @@ ifeq (@ac_external_srtp@,1)
 # External SRTP
 else
 DIRS += srtp
+
+ifeq (@ac_ssl_has_aes_gcm@,0)
+CIPHERS_SRC = crypto/cipher/aes.o crypto/cipher/aes_icm.o       \
+              crypto/cipher/aes_cbc.o
+HASHES_SRC  = crypto/hash/sha1.o crypto/hash/hmac.o 		\
+	      # crypto/hash/tmmhv2.o
+RNG_SRC     = crypto/rng/rand_source.o crypto/rng/prng.o 	\
+	      crypto/rng/ctr_prng.o
+else
+CIPHERS_SRC = crypto/cipher/aes_icm_ossl.o crypto/cipher/aes_gcm_ossl.o
+HASHES_SRC  = crypto/hash/hmac_ossl.o
+RNG_SRC     = crypto/rng/rand_source_ossl.o
+SRTP_OTHER_CFLAGS = -DOPENSSL
+endif
+
+
 endif
 
 ifeq (@ac_pjmedia_resample@,libresample)
diff --git a/third_party/build/srtp/Makefile b/third_party/build/srtp/Makefile
index 7ef0f259..58d4fc58 100644
--- a/third_party/build/srtp/Makefile
+++ b/third_party/build/srtp/Makefile
@@ -1,5 +1,6 @@
 include ../../../build.mak
 include ../../../build/common.mak
+include ../os-$(OS_NAME).mak
 
 export LIBDIR := ../../lib
 
@@ -28,11 +29,9 @@ export _LDFLAGS := $(CC_LDFLAGS) $(OS_LDFLAGS) $(M_LDFLAGS) $(HOST_LDFLAGS) \
 
 # libcrypt.a (the crypto engine) 
 ciphers = crypto/cipher/cipher.o crypto/cipher/null_cipher.o      \
-          crypto/cipher/aes.o crypto/cipher/aes_icm.o             \
-          crypto/cipher/aes_cbc.o
+          $(CIPHERS_SRC)
 
-hashes  = crypto/hash/null_auth.o crypto/hash/sha1.o \
-          crypto/hash/hmac.o crypto/hash/auth.o # crypto/hash/tmmhv2.o 
+hashes  = crypto/hash/null_auth.o crypto/hash/auth.o $(HASHES_SRC)
 
 replay  = crypto/replay/rdb.o crypto/replay/rdbx.o               \
           crypto/replay/ut_sim.o 
@@ -41,7 +40,7 @@ math    = crypto/math/datatypes.o crypto/math/stat.o
 
 ust     = crypto/ust/ust.o 
 
-rng     = crypto/rng/rand_source.o crypto/rng/prng.o crypto/rng/ctr_prng.o
+rng     = $(RNG_SRC)
 
 err     = pjlib/srtp_err.o
 
@@ -54,7 +53,7 @@ cryptobj =  $(ciphers) $(hashes) $(math) $(stat) $(kernel) $(replay)
 
 export SRTP_SRCDIR = ../../srtp
 export SRTP_OBJS = $(cryptobj) $(srtpobj)
-export SRTP_CFLAGS = -DHAVE_CONFIG_H $(_CFLAGS)
+export SRTP_CFLAGS = -DHAVE_CONFIG_H $(_CFLAGS) $(SRTP_OTHER_CFLAGS)
 export SRTP_LDFLAGS = $(PJLIB_LDLIB) $(_LDFLAGS)