Document RC4_ALIGN.

[paraslash.git] / crypt.c

diff --git a/crypt.c b/crypt.c
index 99804470783c04e3758e8800f87f083c4e54f623..8e1814dd3d82e5fd1d50301402faea6b0d9a9934 100644 (file)
--- a/crypt.c
+++ b/crypt.c
@@ -7,13 +7,13 @@
 /** \file crypt.c Openssl-based encryption/decryption routines. */
 
 #include <regex.h>
-#include <dirent.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <openssl/rand.h>
 #include <openssl/err.h>
 #include <openssl/rc4.h>
 #include <openssl/pem.h>
+#include <openssl/sha.h>
 
 #include "para.h"
 #include "error.h"
@@ -219,7 +219,6 @@ int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf,
        return ret < 0? -E_ENCRYPT : ret;
 }
 
-#define RC4_ALIGN 8
 struct stream_cipher {
        RC4_KEY key;
 };
@@ -249,6 +248,13 @@ void sc_free(struct stream_cipher *sc)
        free(sc);
 }
 
+/**
+ * The RC4() implementation of openssl apparently reads and writes data in
+ * blocks of 8 bytes. So we have to make sure our buffer sizes are a multiple
+ * of this.
+ */
+#define RC4_ALIGN 8
+
 /**
  * Encrypt and send a buffer.
  *
@@ -364,3 +370,22 @@ int sc_recv_buffer(struct stream_cipher_context *scc, char *buf, size_t size)
                *buf = '\0';
        return n;
 }
+
+/**
+ * Compute the hash of the given input data.
+ *
+ * \param data Pointer to the data to compute the hash value from.
+ * \param len The length of \a data in bytes.
+ * \param hash Result pointer.
+ *
+ * \a hash must point to an area at least \p HASH_SIZE bytes large.
+ *
+ * \sa sha(3), openssl(1).
+ * */
+void hash_function(const char *data, unsigned long len, unsigned char *hash)
+{
+       SHA_CTX c;
+       SHA1_Init(&c);
+       SHA1_Update(&c, data, len);
+       SHA1_Final(hash, &c);
+}