--- /dev/null
+/* Tunala ("Tunneler with a New Zealand accent")
+ *
+ * Written by Geoff Thorpe, but endorsed/supported by noone. Please use this is
+ * if it's useful or informative to you, but it's only here as a scratchpad for
+ * ideas about how you might (or might not) program with OpenSSL. If you deploy
+ * this is in a mission-critical environment, and have not read, understood,
+ * audited, and modified this code to your satisfaction, and the result is that
+ * all hell breaks loose and you are looking for a new employer, then it proves
+ * nothing except perhaps that Darwinism is alive and well. Let's just say, *I*
+ * don't use this in a mission-critical environment, so it would be stupid for
+ * anyone to assume that it is solid and/or tested enough when even its author
+ * doesn't place that much trust in it. You have been warned.
+ *
+ * With thanks to Cryptographic Appliances, Inc.
+ */
+
+#ifndef _TUNALA_H
+#define _TUNALA_H
+
+/* pull in autoconf fluff */
+#ifndef NO_CONFIG_H
+#include "config.h"
+#else
+/* We don't have autoconf, we have to set all of these unless a tweaked Makefile
+ * tells us not to ... */
+/* headers */
+#ifndef NO_HAVE_SELECT
+#define HAVE_SELECT
+#endif
+#ifndef NO_HAVE_SOCKET
+#define HAVE_SOCKET
+#endif
+#ifndef NO_HAVE_UNISTD_H
+#define HAVE_UNISTD_H
+#endif
+#ifndef NO_HAVE_FCNTL_H
+#define HAVE_FCNTL_H
+#endif
+#ifndef NO_HAVE_LIMITS_H
+#define HAVE_LIMITS_H
+#endif
+/* features */
+#ifndef NO_HAVE_STRSTR
+#define HAVE_STRSTR
+#endif
+#ifndef NO_HAVE_STRTOUL
+#define HAVE_STRTOUL
+#endif
+#endif
+
+#if !defined(HAVE_SELECT) || !defined(HAVE_SOCKET)
+#error "can't build without some network basics like select() and socket()"
+#endif
+
+#include <stdlib.h>
+#ifndef NO_SYSTEM_H
+#include <string.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#include <netdb.h>
+#include <signal.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#endif /* !defined(NO_SYSTEM_H) */
+
+#ifndef NO_OPENSSL
+#include <openssl/err.h>
+#include <openssl/engine.h>
+#include <openssl/ssl.h>
+#endif /* !defined(NO_OPENSSL) */
+
+#ifndef OPENSSL_NO_BUFFER
+/* This is the generic "buffer" type that is used when feeding the
+ * state-machine. It's basically a FIFO with respect to the "adddata" &
+ * "takedata" type functions that operate on it. */
+#define MAX_DATA_SIZE 16384
+typedef struct _buffer_t {
+ unsigned char data[MAX_DATA_SIZE];
+ unsigned int used;
+ /* Statistical values - counts the total number of bytes read in and
+ * read out (respectively) since "buffer_init()" */
+ unsigned long total_in, total_out;
+} buffer_t;
+
+/* Initialise a buffer structure before use */
+void buffer_init(buffer_t *buf);
+/* Cleanup a buffer structure - presently not needed, but if buffer_t is
+ * converted to using dynamic allocation, this would be required - so should be
+ * called to protect against an explosion of memory leaks later if the change is
+ * made. */
+void buffer_close(buffer_t *buf);
+
+/* Basic functions to manipulate buffers */
+
+unsigned int buffer_used(buffer_t *buf); /* How much data in the buffer */
+unsigned int buffer_unused(buffer_t *buf); /* How much space in the buffer */
+int buffer_full(buffer_t *buf); /* Boolean, is it full? */
+int buffer_notfull(buffer_t *buf); /* Boolean, is it not full? */
+int buffer_empty(buffer_t *buf); /* Boolean, is it empty? */
+int buffer_notempty(buffer_t *buf); /* Boolean, is it not empty? */
+unsigned long buffer_total_in(buffer_t *buf); /* Total bytes written to buffer */
+unsigned long buffer_total_out(buffer_t *buf); /* Total bytes read from buffer */
+
+#if 0 /* Currently used only within buffer.c - better to expose only
+ * higher-level functions anyway */
+/* Add data to the tail of the buffer, returns the amount that was actually
+ * added (so, you need to check if return value is less than size) */
+unsigned int buffer_adddata(buffer_t *buf, const unsigned char *ptr,
+ unsigned int size);
+
+/* Take data from the front of the buffer (and scroll the rest forward). If
+ * "ptr" is NULL, this just removes data off the front of the buffer. Return
+ * value is the amount actually removed (can be less than size if the buffer has
+ * too little data). */
+unsigned int buffer_takedata(buffer_t *buf, unsigned char *ptr,
+ unsigned int size);
+
+/* Flushes as much data as possible out of the "from" buffer into the "to"
+ * buffer. Return value is the amount moved. The amount moved can be restricted
+ * to a maximum by specifying "cap" - setting it to -1 means no limit. */
+unsigned int buffer_tobuffer(buffer_t *to, buffer_t *from, int cap);
+#endif
+
+#ifndef NO_IP
+/* Read or write between a file-descriptor and a buffer */
+int buffer_from_fd(buffer_t *buf, int fd);
+int buffer_to_fd(buffer_t *buf, int fd);
+#endif /* !defined(NO_IP) */
+
+#ifndef NO_OPENSSL
+/* Read or write between an SSL or BIO and a buffer */
+void buffer_from_SSL(buffer_t *buf, SSL *ssl);
+void buffer_to_SSL(buffer_t *buf, SSL *ssl);
+void buffer_from_BIO(buffer_t *buf, BIO *bio);
+void buffer_to_BIO(buffer_t *buf, BIO *bio);
+
+/* Callbacks */
+void cb_ssl_info(const SSL *s, int where, int ret);
+void cb_ssl_info_set_output(FILE *fp); /* Called if output should be sent too */
+int cb_ssl_verify(int ok, X509_STORE_CTX *ctx);
+void cb_ssl_verify_set_output(FILE *fp);
+void cb_ssl_verify_set_depth(unsigned int verify_depth);
+void cb_ssl_verify_set_level(unsigned int level);
+RSA *cb_generate_tmp_rsa(SSL *s, int is_export, int keylength);
+#endif /* !defined(NO_OPENSSL) */
+#endif /* !defined(OPENSSL_NO_BUFFER) */
+
+#ifndef NO_TUNALA
+#ifdef OPENSSL_NO_BUFFER
+#error "TUNALA section of tunala.h requires BUFFER support"
+#endif
+typedef struct _state_machine_t {
+ SSL *ssl;
+ BIO *bio_intossl;
+ BIO *bio_fromssl;
+ buffer_t clean_in, clean_out;
+ buffer_t dirty_in, dirty_out;
+} state_machine_t;
+typedef enum {
+ SM_CLEAN_IN, SM_CLEAN_OUT,
+ SM_DIRTY_IN, SM_DIRTY_OUT
+} sm_buffer_t;
+void state_machine_init(state_machine_t *machine);
+void state_machine_close(state_machine_t *machine);
+buffer_t *state_machine_get_buffer(state_machine_t *machine, sm_buffer_t type);
+SSL *state_machine_get_SSL(state_machine_t *machine);
+int state_machine_set_SSL(state_machine_t *machine, SSL *ssl, int is_server);
+/* Performs the data-IO loop and returns zero if the machine should close */
+int state_machine_churn(state_machine_t *machine);
+/* Is used to handle closing conditions - namely when one side of the tunnel has
+ * closed but the other should finish flushing. */
+int state_machine_close_clean(state_machine_t *machine);
+int state_machine_close_dirty(state_machine_t *machine);
+#endif /* !defined(NO_TUNALA) */
+
+#ifndef NO_IP
+/* Initialise anything related to the networking. This includes blocking pesky
+ * SIGPIPE signals. */
+int ip_initialise(void);
+/* ip is the 4-byte ip address (eg. 127.0.0.1 is {0x7F,0x00,0x00,0x01}), port is
+ * the port to listen on (host byte order), and the return value is the
+ * file-descriptor or -1 on error. */
+int ip_create_listener_split(const char *ip, unsigned short port);
+/* Same semantics as above. */
+int ip_create_connection_split(const char *ip, unsigned short port);
+/* Converts a string into the ip/port before calling the above */
+int ip_create_listener(const char *address);
+int ip_create_connection(const char *address);
+/* Just does a string conversion on its own. NB: If accept_all_ip is non-zero,
+ * then the address string could be just a port. Ie. it's suitable for a
+ * listening address but not a connecting address. */
+int ip_parse_address(const char *address, const char **parsed_ip,
+ unsigned short *port, int accept_all_ip);
+/* Accepts an incoming connection through the listener. Assumes selects and
+ * what-not have deemed it an appropriate thing to do. */
+int ip_accept_connection(int listen_fd);
+#endif /* !defined(NO_IP) */
+
+/* These functions wrap up things that can be portability hassles. */
+int int_strtoul(const char *str, unsigned long *val);
+#ifdef HAVE_STRSTR
+#define int_strstr strstr
+#else
+char *int_strstr(const char *haystack, const char *needle);
+#endif
+
+#endif /* !defined(_TUNALA_H) */
projects / cassiopeia.git / blobdiff