+void
+exim_sha_update(hctx * h, const uschar * data, int len)
+{
+gnutls_hash(h->sha, data, len);
+}
+
+
+void
+exim_sha_finish(hctx * h, blob * b)
+{
+b->data = store_get(b->len = h->hashlen);
+gnutls_hash_output(h->sha, b->data);
+}
+
+
+
+#elif defined(SHA_GCRYPT)
+/******************************************************************************/
+
+BOOL
+exim_sha_init(hctx * h, hashmethod m)
+{
+switch (h->method = m)
+ {
+ case HASH_SHA1: h->hashlen = 20; gcry_md_open(&h->sha, GCRY_MD_SHA1, 0); break;
+ case HASH_SHA256: h->hashlen = 32; gcry_md_open(&h->sha, GCRY_MD_SHA256, 0); break;
+ default: h->hashlen = 0; return FALSE;
+ }
+return TRUE;
+}
+
+
+void
+exim_sha_update(hctx * h, const uschar * data, int len)
+{
+gcry_md_write(h->sha, data, len);
+}
+
+
+void
+exim_sha_finish(hctx * h, blob * b)
+{
+b->data = store_get(b->len = h->hashlen);
+memcpy(b->data, gcry_md_read(h->sha, 0), h->hashlen);
+}
+
+
+
+
+#elif defined(SHA_POLARSSL)
+/******************************************************************************/
+
+BOOL
+exim_sha_init(hctx * h, hashmethod m)
+{
+switch (h->method = m)
+ {
+ case HASH_SHA1: h->hashlen = 20; sha1_starts(&h->u.sha1); break;
+ case HASH_SHA256: h->hashlen = 32; sha2_starts(&h->u.sha2, 0); break;
+ default: h->hashlen = 0; return FALSE;
+ }
+return TRUE;
+}
+
+
+void
+exim_sha_update(hctx * h, const uschar * data, int len)
+{
+switch (h->method)
+ {
+ case HASH_SHA1: sha1_update(h->u.sha1, US data, len); break;
+ case HASH_SHA256: sha2_update(h->u.sha2, US data, len); break;
+ }
+}
+
+
+void
+exim_sha_finish(hctx * h, blob * b)
+{
+b->data = store_get(b->len = h->hashlen);
+switch (h->method)
+ {
+ case HASH_SHA1: sha1_finish(h->u.sha1, b->data); break;
+ case HASH_SHA256: sha2_finish(h->u.sha2, b->data); break;
+ }
+}
+
+
+
+
+#elif defined(SHA_NATIVE)
+/******************************************************************************/
+/* Only sha-1 supported */