+/* Extracts an SSH-marshalled string from the start of *data. If
+ * successful (*datalen is not too small), advances data/datalen past
+ * the string and returns a pointer to the string itself and its
+ * length in *stringlen. Otherwise does nothing and returns NULL.
+ *
+ * Like strchr, this function can discard const from its parameter.
+ * Treat it as if it was a family of two functions, one returning a
+ * non-const string given a non-const pointer, and one taking and
+ * returning const. */
+void *get_ssh_string(int *datalen, const void **data, int *stringlen);
+/* Extracts an SSH uint32, similarly. Returns TRUE on success, and
+ * leaves the extracted value in *ret. */
+int get_ssh_uint32(int *datalen, const void **data, unsigned *ret);
+/* Given a not-necessarily-zero-terminated string in (length,data)
+ * form, check if it equals an ordinary C zero-terminated string. */
+int match_ssh_id(int stringlen, const void *string, const char *id);
+
+char *buildinfo(const char *newline);
+