openssl: use Genode specific RAND backend

The backend merely provides simpler access to '/dev/random' because
on Genode the common random device checks are unnecessary.

Fixes #1236.

repos/libports/lib/mk/libcrypto.mk

@@ -6,7 +6,8 @@ SHARED_LIB = yes
 LIBS += libc
 
 CC_OPT += -DDSO_DLFCN -DHAVE_DLFCN_H -Wa,--noexecstack -DL_ENDIAN -DTERMIOS \
-          -DOPENSSL_NO_ASM
+          -DOPENSSL_NO_ASM -DGETPID_IS_MEANINGLESS
+CC_OPT += -DRAND_GENODE
 
 #
 # crypto base source

repos/libports/ports/openssl.hash

@@ -1 +1 @@
-50bfa7824abc38d4d1eecbc80d8433639c0cb731
+7b4517a076012f43036912dcc693fb6b035ddf3c

repos/libports/ports/openssl.port

@@ -37,3 +37,6 @@ src/lib/openssl/x86_64/rc4_md5.s:
 	$(VERBOSE)mkdir -p $(dir $@)
 	$(VERBOSE)perl src/lib/openssl/crypto/rc4/asm/rc4-md5-x86_64.pl \
 		src/lib/openssl/crypto/perlasm/x86as.pl > $@
+
+PATCHES := src/lib/openssl/rand_unix_c.patch
+PATCH_OPT := -p1 -d src/lib/openssl

repos/libports/src/lib/openssl/rand_unix_c.patch

@@ -0,0 +1,29 @@
+diff --git a/crypto/rand/rand_unix.c b/crypto/rand/rand_unix.c
+index e3a6557..27b26e4 100644
+--- a/crypto/rand/rand_unix.c
++++ b/crypto/rand/rand_unix.c
+@@ -233,6 +233,24 @@ int RAND_poll(void)
+ 
+ 	return 1;
+ }
++#elif defined RAND_GENODE
++int RAND_poll(void)
++{
++	unsigned char buf[ENTROPY_NEEDED];
++
++	int fd = open("/dev/random", O_RDONLY);
++	if (fd == -1) {
++		perror("open");
++		return 0;
++	}
++
++	read(fd, buf, sizeof(buf)); /* XXX check read */
++
++	RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
++	memset(buf, 0, sizeof(buf)); /* XXX make explicit */
++
++	return 1;
++}
+ #else /* !defined(__OpenBSD__) */
+ int RAND_poll(void)
+ {