diff --git a/src/crypto/axtls_sha1.c b/src/crypto/axtls_sha1.c
new file mode 100644
index 00000000..17c08797
--- /dev/null
+++ b/src/crypto/axtls_sha1.c
@@ -0,0 +1,26 @@
+#include "crypto/axtls/crypto.h"
+#include <gpxe/crypto.h>
+#include <gpxe/sha1.h>
+
+static void sha1_init ( void *ctx ) {
+	SHA1Init ( ctx );
+}
+
+static void sha1_update ( void *ctx, const void *data, void *dst __unused,
+			  size_t len ) {
+	SHA1Update ( ctx, data, len );
+}
+
+static void sha1_final ( void *ctx, void *out ) {
+	SHA1Final ( ctx, out );
+}
+
+struct crypto_algorithm sha1_algorithm = {
+	.name		= "sha1",
+	.ctxsize	= sizeof ( SHA1_CTX ),
+	.blocksize	= 64,
+	.digestsize	= SHA1_SIZE,
+	.init		= sha1_init,
+	.encode		= sha1_update,
+	.final		= sha1_final,
+};
diff --git a/src/include/gpxe/sha1.h b/src/include/gpxe/sha1.h
new file mode 100644
index 00000000..1425d54c
--- /dev/null
+++ b/src/include/gpxe/sha1.h
@@ -0,0 +1,8 @@
+#ifndef _GPXE_SHA1_H
+#define _GPXE_SHA1_H
+
+struct crypto_algorithm;
+
+extern struct crypto_algorithm sha1_algorithm;
+
+#endif /* _GPXE_SHA1_H */