X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=crypt.c;h=17026cc63525c5527f63fb95c27242dc272add23;hp=f33f769f6f035c18946c21fea064b37052802583;hb=0a0a3db1d4a541abe8442fd3cbfcae6636874d1b;hpb=f0e41e36c3f1a3a5bb6ff66d92d2814391d8f908

diff --git a/crypt.c b/crypt.c
index f33f769f..17026cc6 100644
--- a/crypt.c
+++ b/crypt.c
@@ -317,6 +317,30 @@ int sc_recv_bin_buffer(struct stream_cipher_context *scc, char *buf,
 	return ret;
 }
 
+void sc_crypt(struct stream_cipher *sc, struct iovec *src, struct iovec *dst)
+{
+	size_t len = src->iov_len, l1, l2;
+	RC4_KEY *key = &sc->key;
+
+	assert(len > 0);
+	assert(len < ((typeof(src->iov_len))-1) / 2);
+	l1 = ROUND_DOWN(len, RC4_ALIGN);
+	l2 = ROUND_UP(len, RC4_ALIGN);
+
+	*dst = (typeof(*dst)) {
+		/* Add one for the terminating zero byte. */
+		.iov_base = para_malloc(l2 + 1),
+		.iov_len = len
+	};
+	RC4(key, l1, src->iov_base, dst->iov_base);
+	if (len > l1) {
+		unsigned char remainder[RC4_ALIGN] = "";
+		memcpy(remainder, src->iov_base + l1, len - l1);
+		RC4(key, len - l1, remainder, dst->iov_base + l1);
+	}
+	((char *)dst->iov_base)[len] = '\0';
+}
+
 void hash_function(const char *data, unsigned long len, unsigned char *hash)
 {
 	SHA_CTX c;