+/* -*- Mode: C; c-file-style: "bsd" -*- */
+/*
+ * easy-tls.c -- generic TLS proxy.
+ * $Id: easy-tls.c,v 1.1 2001/09/17 19:06:57 bodo Exp $
+ */
+/*
+ (c) Copyright 1999 Bodo Moeller. All rights reserved.
+
+ This is free software; you can redistributed and/or modify it
+ unter the terms of either
+ - the GNU General Public License as published by the
+ Free Software Foundation, version 1, or (at your option)
+ any later version,
+ or
+ - the following license:
+*/
+/*
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that each of the following
+ * conditions is met:
+ *
+ * 1. Redistributions qualify as "freeware" or "Open Source Software" under
+ * one of the following terms:
+ *
+ * (a) Redistributions are made at no charge beyond the reasonable cost of
+ * materials and delivery.
+ *
+ * (b) Redistributions are accompanied by a copy of the Source Code
+ * or by an irrevocable offer to provide a copy of the Source Code
+ * for up to three years at the cost of materials and delivery.
+ * Such redistributions must allow further use, modification, and
+ * redistribution of the Source Code under substantially the same
+ * terms as this license.
+ *
+ * 2. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 3. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 4. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by Bodo Moeller."
+ * (If available, substitute umlauted o for oe.)
+ *
+ * 5. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by Bodo Moeller."
+ *
+ * THIS SOFTWARE IS PROVIDED BY BODO MOELLER ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BODO MOELLER OR
+ * HIS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+/*
+ * Attribution for OpenSSL library:
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com). This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ * This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)
+ */
+
+static char const rcsid[] =
+"$Id: easy-tls.c,v 1.1 2001/09/17 19:06:57 bodo Exp $";
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+
+#include <openssl/crypto.h>
+#include <openssl/dh.h>
+#include <openssl/dsa.h>
+#include <openssl/err.h>
+#include <openssl/evp.h>
+#include <openssl/opensslv.h>
+#include <openssl/pem.h>
+#include <openssl/rand.h>
+#ifndef NO_RSA
+ #include <openssl/rsa.h>
+#endif
+#include <openssl/ssl.h>
+#include <openssl/x509.h>
+#include <openssl/x509_vfy.h>
+
+#if OPENSSL_VERSION_NUMBER < 0x00904000L /* 0.9.4-dev */
+# error "This program needs OpenSSL 0.9.4 or later."
+#endif
+
+#include "easy-tls.h" /* include after <openssl/ssl.h> if both are needed */
+
+#if TLS_INFO_SIZE > PIPE_BUF
+# if PIPE_BUF < 512
+# error "PIPE_BUF < 512" /* non-POSIX */
+# endif
+# error "TLS_INFO_SIZE > PIPE_BUF"
+#endif
+
+/*****************************************************************************/
+
+#ifdef TLS_APP
+# include TLS_APP
+#endif
+
+/* Applications can define:
+ * TLS_APP_PROCESS_INIT -- void ...(int fd, int client_p, void *apparg)
+ * TLS_CUMULATE_ERRORS
+ * TLS_ERROR_BUFSIZ
+ * TLS_APP_ERRFLUSH -- void ...(int child_p, char *, size_t, void *apparg)
+ */
+
+#ifndef TLS_APP_PROCESS_INIT
+# define TLS_APP_PROCESS_INIT(fd, client_p, apparg) ((void) 0)
+#endif
+
+#ifndef TLS_ERROR_BUFSIZ
+# define TLS_ERROR_BUFSIZ (10*160)
+#endif
+#if TLS_ERROR_BUFSIZ < 2 /* {'\n',0} */
+# error "TLS_ERROR_BUFSIZE is too small."
+#endif
+
+#ifndef TLS_APP_ERRFLUSH
+# define TLS_APP_ERRFLUSH tls_app_errflush
+static void
+tls_app_errflush(int child_p, char *errbuf, size_t num, void *apparg)
+{
+ fputs(errbuf, stderr);
+}
+#endif
+
+/*****************************************************************************/
+
+#ifdef DEBUG_TLS
+# define DEBUG_MSG(x) fprintf(stderr," %s\n",x)
+# define DEBUG_MSG2(x,y) fprintf(stderr, " %s: %d\n",x,y)
+static int tls_loop_count = 0;
+static int tls_select_count = 0;
+#else
+# define DEBUG_MSG(x) (void)0
+# define DEBUG_MSG2(x,y) (void)0
+#endif
+
+static void tls_rand_seed_uniquely(void);
+static void tls_proxy(int clear_fd, int tls_fd, int info_fd, SSL_CTX *ctx, int client_p);
+static int tls_socket_nonblocking(int fd);
+
+static int tls_child_p = 0;
+static void *tls_child_apparg;
+
+
+struct tls_start_proxy_args
+tls_start_proxy_defaultargs(void)
+{
+ struct tls_start_proxy_args ret;
+
+ ret.fd = -1;
+ ret.client_p = -1;
+ ret.ctx = NULL;
+ ret.pid = NULL;
+ ret.infofd = NULL;
+
+ return ret;
+}
+
+/* Slice in TLS proxy process at fd.
+ * Return value:
+ * 0 ok (*pid is set to child's PID if pid != NULL),
+ * < 0 look at errno
+ * > 0 other error
+ * (return value encodes place of error)
+ *
+ */
+int
+tls_start_proxy(struct tls_start_proxy_args a, void *apparg)
+{
+ int fds[2] = {-1, -1};
+ int infofds[2] = {-1, -1};
+ int r, getfd, getfl;
+ int ret;
+
+ DEBUG_MSG2("tls_start_proxy fd", a.fd);
+ DEBUG_MSG2("tls_start_proxy client_p", a.client_p);
+
+ if (a.fd == -1 || a.client_p == -1 || a.ctx == NULL)
+ return 1;
+
+ if (a.pid != NULL) {
+ *a.pid = 0;
+ }
+ if (a.infofd != NULL) {
+ *a.infofd = -1;
+ }
+
+ r = socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
+ if (r == -1)
+ return -1;
+ if (a.fd >= FD_SETSIZE || fds[0] >= FD_SETSIZE) {
+ ret = 2;
+ goto err;
+ }
+ if (a.infofd != NULL) {
+ r = pipe(infofds);
+ if (r == -1) {
+ ret = -3;
+ goto err;
+ }
+ }
+
+ r = fork();
+ if (r == -1) {
+ ret = -4;
+ goto err;
+ }
+ if (r == 0) {
+ DEBUG_MSG("fork");
+ tls_child_p = 1;
+ tls_child_apparg = apparg;
+ close(fds[1]);
+ if (infofds[0] != -1)
+ close(infofds[0]);
+ TLS_APP_PROCESS_INIT(a.fd, a.client_p, apparg);
+ DEBUG_MSG("TLS_APP_PROCESS_INIT");
+ tls_proxy(fds[0], a.fd, infofds[1], a.ctx, a.client_p);
+ exit(0);
+ }
+ if (a.pid != NULL)
+ *a.pid = r;
+ if (infofds[1] != -1) {
+ close(infofds[1]);
+ infofds[1] = -1;
+ }
+ /* install fds[1] in place of fd: */
+ close(fds[0]);
+ fds[0] = -1;
+ getfd = fcntl(a.fd, F_GETFD);
+ getfl = fcntl(a.fd, F_GETFL);
+ r = dup2(fds[1], a.fd);
+ close(fds[1]);
+ fds[1] = -1;
+ if (r == -1) {
+ ret = -5;
+ goto err;
+ }
+ if (getfd != 1)
+ fcntl(a.fd, F_SETFD, getfd);
+ if (getfl & O_NONBLOCK)
+ (void)tls_socket_nonblocking(a.fd);
+ if (a.infofd != NULL)
+ *a.infofd = infofds[0];
+ return 0;
+
+ err:
+ if (fds[0] != -1)
+ close(fds[0]);
+ if (fds[1] != -1)
+ close(fds[1]);
+ if (infofds[0] != -1)
+ close(infofds[0]);
+ if (infofds[1] != -1)
+ close(infofds[1]);
+ return ret;
+}
+
+/*****************************************************************************/
+
+static char errbuf[TLS_ERROR_BUFSIZ];
+static size_t errbuf_i = 0;
+
+static void
+tls_errflush(void *apparg)
+{
+ if (errbuf_i == 0)
+ return;
+
+ assert(errbuf_i < sizeof errbuf);
+ assert(errbuf[errbuf_i] == 0);
+ if (errbuf_i == sizeof errbuf - 1) {
+ /* make sure we have a newline, even if string has been truncated */
+ errbuf[errbuf_i - 1] = '\n';
+ }
+
+ /* TLS_APP_ERRFLUSH may modify the string as needed,
+ * e.g. substitute other characters for \n for convenience */
+ TLS_APP_ERRFLUSH(tls_child_p, errbuf, errbuf_i, apparg);
+
+ errbuf_i = 0;
+}
+
+static void
+tls_errprintf(int flush, void *apparg, const char *fmt, ...)
+{
+ va_list args;
+ int r;
+
+ if (errbuf_i < sizeof errbuf - 1) {
+ size_t n;
+
+ va_start(args, fmt);
+ n = (sizeof errbuf) - errbuf_i;
+ r = vsnprintf(errbuf + errbuf_i, n, fmt, args);
+ if (r >= n)
+ r = n - 1;
+ if (r >= 0) {
+ errbuf_i += r;
+ } else {
+ errbuf_i = sizeof errbuf - 1;
+ errbuf[errbuf_i] = '\0';
+ }
+ assert(errbuf_i < sizeof errbuf);
+ assert(errbuf[errbuf_i] == 0);
+ }
+#ifndef TLS_CUMULATE_ERRORS
+ tls_errflush(apparg);
+#else
+ if (flush)
+ tls_errflush(apparg);
+#endif
+}
+
+/* app_prefix.. are for additional information provided by caller.
+ * If OpenSSL error queue is empty, print default_text ("???" if NULL).
+ */
+static char *
+tls_openssl_errors(const char *app_prefix_1, const char *app_prefix_2, const char *default_text, void *apparg)
+{
+ static char reasons[255];
+ size_t reasons_i;
+ unsigned long err;
+ const char *file;
+ int line;
+ const char *data;
+ int flags;
+ char *errstring;
+ int printed_something = 0;
+
+ reasons_i = 0;
+
+ assert(app_prefix_1 != NULL);
+ assert(app_prefix_2 != NULL);
+
+ if (default_text == NULL)
+ default_text = "???";
+
+ while ((err = ERR_get_error_line_data(&file,&line,&data,&flags)) != 0) {
+ if (reasons_i < sizeof reasons) {
+ size_t n;
+ int r;
+
+ n = (sizeof reasons) - reasons_i;
+ r = snprintf(reasons + reasons_i, n, "%s%s", (reasons_i > 0 ? ", " : ""), ERR_reason_error_string(err));
+ if (r >= n)
+ r = n - 1;
+ if (r >= 0) {
+ reasons_i += r;
+ } else {
+ reasons_i = sizeof reasons;
+ }
+ assert(reasons_i <= sizeof reasons);
+ }
+
+ errstring = ERR_error_string(err, NULL);
+ assert(errstring != NULL);
+ tls_errprintf(0, apparg, "OpenSSL error%s%s: %s:%s:%d:%s\n", app_prefix_1, app_prefix_2, errstring, file, line, (flags & ERR_TXT_STRING) ? data : "");
+ printed_something = 1;
+ }
+
+ if (!printed_something) {
+ assert(reasons_i == 0);
+ snprintf(reasons, sizeof reasons, "%s", default_text);
+ tls_errprintf(0, apparg, "OpenSSL error%s%s: %s\n", app_prefix_1, app_prefix_2, default_text);
+ }
+
+#ifdef TLS_CUMULATE_ERRORS
+ tls_errflush(apparg);
+#endif
+ assert(errbuf_i == 0);
+
+ return reasons;
+}
+
+/*****************************************************************************/
+
+static int tls_init_done = 0;
+
+static int
+tls_init(void *apparg)
+{
+ if (tls_init_done)
+ return 0;
+
+ SSL_load_error_strings();
+ if (!SSL_library_init() /* aka SSLeay_add_ssl_algorithms() */ ) {
+ tls_errprintf(1, apparg, "SSL_library_init failed.\n");
+ return -1;
+ }
+ tls_init_done = 1;
+ tls_rand_seed();
+ return 0;
+}
+
+/*****************************************************************************/
+
+static void
+tls_rand_seed_uniquely(void)
+{
+ struct {
+ pid_t pid;
+ time_t time;
+ void *stack;
+ } data;
+
+ data.pid = getpid();
+ data.time = time(NULL);
+ data.stack = (void *)&data;
+
+ RAND_seed((const void *)&data, sizeof data);
+}
+
+void
+tls_rand_seed(void)
+{
+ struct {
+ struct utsname uname;
+ int uname_1;
+ int uname_2;
+ uid_t uid;
+ uid_t euid;
+ gid_t gid;
+ gid_t egid;
+ } data;
+
+ data.uname_1 = uname(&data.uname);
+ data.uname_2 = errno; /* Let's hope that uname fails randomly :-) */
+
+ data.uid = getuid();
+ data.euid = geteuid();
+ data.gid = getgid();
+ data.egid = getegid();
+
+ RAND_seed((const void *)&data, sizeof data);
+ tls_rand_seed_uniquely();
+}
+
+static int tls_rand_seeded_p = 0;
+
+#define my_MIN_SEED_BYTES 256 /* struct stat can be larger than 128 */
+int
+tls_rand_seed_from_file(const char *filename, size_t n, void *apparg)
+{
+ /* Seed OpenSSL's random number generator from file.
+ Try to read n bytes if n > 0, whole file if n == 0. */
+
+ int r;
+
+ if (tls_init(apparg) == -1)
+ return -1;
+ tls_rand_seed();
+
+ r = RAND_load_file(filename, (n > 0 && n < LONG_MAX) ? (long)n : LONG_MAX);
+ /* r is the number of bytes filled into the random number generator,
+ * which are taken from "stat(filename, ...)" in addition to the
+ * file contents.
+ */
+ assert(1 < my_MIN_SEED_BYTES);
+ /* We need to detect at least those cases when the file does not exist
+ * at all. With current versions of OpenSSL, this should do it: */
+ if (n == 0)
+ n = my_MIN_SEED_BYTES;
+ if (r < n) {
+ tls_errprintf(1, apparg, "rand_seed_from_file: could not read %d bytes from %s.\n", n, filename);
+ return -1;
+ } else {
+ tls_rand_seeded_p = 1;
+ return 0;
+ }
+}
+
+void
+tls_rand_seed_from_memory(const void *buf, size_t n)
+{
+ size_t i = 0;
+
+ while (i < n) {
+ size_t rest = n - i;
+ int chunk = rest < INT_MAX ? (int)rest : INT_MAX;
+ RAND_seed((const char *)buf + i, chunk);
+ i += chunk;
+ }
+ tls_rand_seeded_p = 1;
+}
+
+
+/*****************************************************************************/
+
+struct tls_x509_name_string {
+ char str[100];
+};
+
+static void
+tls_get_x509_subject_name_oneline(X509 *cert, struct tls_x509_name_string *namestring)
+{
+ X509_NAME *name;
+
+ if (cert == NULL) {
+ namestring->str[0] = '\0';
+ return;
+ }
+
+ name = X509_get_subject_name(cert); /* does not increment any reference counter */
+
+ assert(sizeof namestring->str >= 4); /* "?" or "...", plus 0 */
+
+ if (name == NULL) {
+ namestring->str[0] = '?';
+ namestring->str[1] = 0;
+ } else {
+ size_t len;
+
+ X509_NAME_oneline(name, namestring->str, sizeof namestring->str);
+ len = strlen(namestring->str);
+ assert(namestring->str[len] == 0);
+ assert(len < sizeof namestring->str);
+
+ if (len+1 == sizeof namestring->str) {
+ /* (Probably something was cut off.)
+ * Does not really work -- X509_NAME_oneline truncates after
+ * name components, we cannot tell from the result whether
+ * anything is missing. */
+
+ assert(namestring->str[len] == 0);
+ namestring->str[--len] = '.';
+ namestring->str[--len] = '.';
+ namestring->str[--len] = '.';
+ }
+ }
+}
+
+/*****************************************************************************/
+
+/* to hinder OpenSSL from asking for passphrases */
+static int
+no_passphrase_callback(char *buf, int num, int w, void *arg)
+{
+ return -1;
+}
+
+static int
+verify_dont_fail_cb(X509_STORE_CTX *c)
+{
+ int i;
+
+ i = X509_verify_cert(c); /* sets c->error */
+#if OPENSSL_VERSION_NUMBER >= 0x00905000L /* don't allow unverified
+ * certificates -- they could
+ * survive session reuse, but
+ * OpenSSL < 0.9.5-dev does not
+ * preserve their verify_result */
+ if (i == 0)
+ return 1;
+ else
+#endif
+ return i;
+}
+
+static DH *tls_dhe1024 = NULL; /* generating these takes a while, so do it just once */
+
+void
+tls_set_dhe1024(int i, void *apparg)
+{
+ DSA *dsaparams;
+ DH *dhparams;
+ const char *seed[] = { ";-) :-( :-) :-( ",
+ ";-) :-( :-) :-( ",
+ "Random String no. 12",
+ ";-) :-( :-) :-( ",
+ "hackers have even mo", /* from jargon file */
+ };
+ unsigned char seedbuf[20];
+
+ tls_init(apparg);
+ if (i >= 0) {
+ i %= sizeof seed / sizeof seed[0];
+ assert(strlen(seed[i]) == 20);
+ memcpy(seedbuf, seed[i], 20);
+ dsaparams = DSA_generate_parameters(1024, seedbuf, 20, NULL, NULL, 0, NULL);
+ } else {
+ /* random parameters (may take a while) */
+ dsaparams = DSA_generate_parameters(1024, NULL, 0, NULL, NULL, 0, NULL);
+ }
+
+ if (dsaparams == NULL) {
+ tls_openssl_errors("", "", NULL, apparg);
+ return;
+ }
+ dhparams = DSA_dup_DH(dsaparams);
+ DSA_free(dsaparams);
+ if (dhparams == NULL) {
+ tls_openssl_errors("", "", NULL, apparg);
+ return;
+ }
+ if (tls_dhe1024 != NULL)
+ DH_free(tls_dhe1024);
+ tls_dhe1024 = dhparams;
+}
+
+struct tls_create_ctx_args
+tls_create_ctx_defaultargs(void)
+{
+ struct tls_create_ctx_args ret;
+
+ ret.client_p = 0;
+ ret.certificate_file = NULL;
+ ret.key_file = NULL;
+ ret.ca_file = NULL;
+ ret.verify_depth = -1;
+ ret.fail_unless_verified = 0;
+ ret.export_p = 0;
+
+ return ret;
+}
+
+SSL_CTX *
+tls_create_ctx(struct tls_create_ctx_args a, void *apparg)
+{
+ int r;
+ static long context_num = 0;
+ SSL_CTX *ret;
+ const char *err_pref_1 = "", *err_pref_2 = "";
+
+ if (tls_init(apparg) == -1)
+ return NULL;
+
+ ret = SSL_CTX_new((a.client_p? SSLv23_client_method:SSLv23_server_method)());
+
+ if (ret == NULL)
+ goto err;
+
+ SSL_CTX_set_default_passwd_cb(ret, no_passphrase_callback);
+ SSL_CTX_set_mode(ret, SSL_MODE_ENABLE_PARTIAL_WRITE);
+
+ if ((a.certificate_file != NULL) || (a.key_file != NULL)) {
+ if (a.key_file == NULL) {
+ tls_errprintf(1, apparg, "Need a key file.\n");
+ goto err_return;
+ }
+ if (a.certificate_file == NULL) {
+ tls_errprintf(1, apparg, "Need a certificate chain file.\n");
+ goto err_return;
+ }
+
+ if (!SSL_CTX_use_PrivateKey_file(ret, a.key_file, SSL_FILETYPE_PEM))
+ goto err;
+ if (!tls_rand_seeded_p) {
+ /* particularly paranoid people may not like this --
+ * so provide your own random seeding before calling this */
+ if (tls_rand_seed_from_file(a.key_file, 0, apparg) == -1)
+ goto err_return;
+ }
+ if (!SSL_CTX_use_certificate_chain_file(ret, a.certificate_file))
+ goto err;
+ if (!SSL_CTX_check_private_key(ret)) {
+ tls_errprintf(1, apparg, "Private key \"%s\" does not match certificate \"%s\".\n", a.key_file, a.certificate_file);
+ goto err_peek;
+ }
+ }
+
+ if ((a.ca_file != NULL) || (a.verify_depth > 0)) {
+ context_num++;
+ r = SSL_CTX_set_session_id_context(ret, (const void *)&context_num, (unsigned int)sizeof context_num);
+ if (!r)
+ goto err;
+
+ SSL_CTX_set_verify(ret, SSL_VERIFY_PEER | (a.fail_unless_verified ? SSL_VERIFY_FAIL_IF_NO_PEER_CERT : 0), 0);
+ if (!a.fail_unless_verified)
+ SSL_CTX_set_cert_verify_callback(ret, verify_dont_fail_cb, NULL);
+
+ if (a.verify_depth > 0)
+ SSL_CTX_set_verify_depth(ret, a.verify_depth);
+
+ if (a.ca_file != NULL) {
+ r = SSL_CTX_load_verify_locations(ret, a.ca_file, NULL /* no CA-directory */); /* does not report failure if file does not exist ... */
+ if (!r) {
+ err_pref_1 = " while processing certificate file ";
+ err_pref_2 = a.ca_file;
+ goto err;
+ }
+
+ if (!a.client_p) {
+ /* SSL_load_client_CA_file is a misnomer, it just creates a list of CNs. */
+ SSL_CTX_set_client_CA_list(ret, SSL_load_client_CA_file(a.ca_file));
+ /* SSL_CTX_set_client_CA_list does not have a return value;
+ * it does not really need one, but make sure
+ * (we really test if SSL_load_client_CA_file worked) */
+ if (SSL_CTX_get_client_CA_list(ret) == NULL) {
+ tls_errprintf(1, apparg, "Could not set client CA list from \"%s\".\n", a.ca_file);
+ goto err_peek;
+ }
+ }
+ }
+ }
+
+ if (!a.client_p) {
+ if (tls_dhe1024 == NULL) {
+ int i;
+
+ RAND_bytes((unsigned char *) &i, sizeof i);
+ /* make sure that i is non-negative -- pick one of the provided
+ * seeds */
+ if (i < 0)
+ i = -i;
+ if (i < 0)
+ i = 0;
+ tls_set_dhe1024(i, apparg);
+ if (tls_dhe1024 == NULL)
+ goto err_return;
+ }
+
+ if (!SSL_CTX_set_tmp_dh(ret, tls_dhe1024))
+ goto err;
+
+ /* avoid small subgroup attacks: */
+ SSL_CTX_set_options(ret, SSL_OP_SINGLE_DH_USE);
+ }
+
+#ifndef NO_RSA
+ if (!a.client_p && a.export_p) {
+ RSA *tmpkey;
+
+ tmpkey = RSA_generate_key(512, RSA_F4, 0, NULL);
+ if (tmpkey == NULL)
+ goto err;
+ if (!SSL_CTX_set_tmp_rsa(ret, tmpkey)) {
+ RSA_free(tmpkey);
+ goto err;
+ }
+ RSA_free(tmpkey); /* SSL_CTX_set_tmp_rsa uses a duplicate. */
+ }
+#endif
+
+ return ret;
+
+ err_peek:
+ if (!ERR_peek_error())
+ goto err_return;
+ err:
+ tls_openssl_errors(err_pref_1, err_pref_2, NULL, apparg);
+ err_return:
+ if (ret != NULL)
+ SSL_CTX_free(ret);
+ return NULL;
+}
+
+
+/*****************************************************************************/
+
+static int
+tls_socket_nonblocking(int fd)
+{
+ int v, r;
+
+ v = fcntl(fd, F_GETFL, 0);
+ if (v == -1) {
+ if (errno == EINVAL)
+ return 0; /* already shut down -- ignore */
+ return -1;
+ }
+ r = fcntl(fd, F_SETFL, v | O_NONBLOCK);
+ if (r == -1) {
+ if (errno == EINVAL)
+ return 0; /* already shut down -- ignore */
+ return -1;
+ }
+ return 0;
+}
+
+static int
+max(int a, int b)
+{
+ return a > b ? a : b;
+}
+
+static void
+tls_sockets_select(int read_select_1, int read_select_2, int write_select_1, int write_select_2, int seconds /* timeout, -1 means no timeout */)
+{
+ int maxfd, n;
+ fd_set reads, writes;
+ struct timeval timeout;
+ struct timeval *timeout_p;
+
+ assert(read_select_1 >= -1 && read_select_2 >= -1 && write_select_1 >= -1 && write_select_2 >= -1);
+ assert(read_select_1 < FD_SETSIZE && read_select_2 < FD_SETSIZE -1 && write_select_1 < FD_SETSIZE -1 && write_select_2 < FD_SETSIZE -1);
+
+ maxfd = max(max(read_select_1, read_select_2), max(write_select_1, write_select_2));
+ assert(maxfd >= 0);
+
+ FD_ZERO(&reads);
+ FD_ZERO(&writes);
+
+ for(n = 0; n < 4; ++n) {
+ int i = n % 2;
+ int w = n >= 2;
+ /* loop over all (i, w) in {0,1}x{0,1} */
+ int fd;
+
+ if (i == 0 && w == 0)
+ fd = read_select_1;
+ else if (i == 1 && w == 0)
+ fd = read_select_2;
+ else if (i == 0 && w == 1)
+ fd = write_select_1;
+ else {
+ assert(i == 1 && w == 1);
+ fd = write_select_2;
+ }
+
+ if (fd >= 0) {
+ if (w == 0)
+ FD_SET(fd, &reads);
+ else /* w == 1 */
+ FD_SET(fd, &writes);
+ }
+ }
+
+ if (seconds >= 0) {
+ timeout.tv_sec = seconds;
+ timeout.tv_usec = 0;
+ timeout_p = &timeout;
+ } else
+ timeout_p = NULL;
+
+ DEBUG_MSG2("select no.", ++tls_select_count);
+ select(maxfd + 1, &reads, &writes, (fd_set *) NULL, timeout_p);
+ DEBUG_MSG("cont.");
+}
+
+/*****************************************************************************/
+
+#define TUNNELBUFSIZE (16*1024)
+struct tunnelbuf {
+ char buf[TUNNELBUFSIZE];
+ size_t len;
+ size_t offset;
+};
+
+static int tls_connect_attempt(SSL *, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref);
+
+static int tls_accept_attempt(SSL *, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref);
+
+static int tls_write_attempt(SSL *, struct tunnelbuf *, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref);
+
+static int tls_read_attempt(SSL *, struct tunnelbuf *, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref);
+
+static int write_attempt(int fd, struct tunnelbuf *, int *select, int *closed, int *progress);
+
+static int read_attempt(int fd, struct tunnelbuf *, int *select, int *closed, int *progress);
+
+static void write_info(SSL *ssl, int *info_fd)
+{
+ if (*info_fd != -1) {
+ long v;
+ int v_ok;
+ struct tls_x509_name_string peer;
+ char infobuf[TLS_INFO_SIZE];
+ int r;
+
+ DEBUG_MSG("write_info");
+ v = SSL_get_verify_result(ssl);
+ v_ok = (v == X509_V_OK) ? 'A' : 'E'; /* Auth./Error */
+ {
+ X509 *peercert;
+
+ peercert = SSL_get_peer_certificate(ssl);
+ tls_get_x509_subject_name_oneline(peercert, &peer);
+ if (peercert != NULL)
+ X509_free(peercert);
+ }
+ if (peer.str[0] == '\0')
+ v_ok = '0'; /* no cert at all */
+ else
+ if (strchr(peer.str, '\n')) {
+ /* should not happen, but make sure */
+ *strchr(peer.str, '\n') = '\0';
+ }
+ r = snprintf(infobuf, sizeof infobuf, "%c:%s\n%s\n", v_ok, X509_verify_cert_error_string(v), peer.str);
+ DEBUG_MSG2("snprintf", r);
+ if (r == -1 || r >= sizeof infobuf)
+ r = sizeof infobuf - 1;
+ write(*info_fd, infobuf, r);
+ close (*info_fd);
+ *info_fd = -1;
+ }
+}
+
+
+/* tls_proxy expects that all fds are closed after return */
+static void
+tls_proxy(int clear_fd, int tls_fd, int info_fd, SSL_CTX *ctx, int client_p)
+{
+ struct tunnelbuf clear_to_tls, tls_to_clear;
+ SSL *ssl;
+ BIO *rbio, *wbio;
+ int closed, in_handshake;
+ const char *err_pref_1 = "", *err_pref_2 = "";
+ const char *err_def = NULL;
+
+ assert(clear_fd != -1);
+ assert(tls_fd != -1);
+ assert(clear_fd < FD_SETSIZE);
+ assert(tls_fd < FD_SETSIZE);
+ /* info_fd may be -1 */
+ assert(ctx != NULL);
+
+ tls_rand_seed_uniquely();
+
+ tls_socket_nonblocking(clear_fd);
+ DEBUG_MSG2("clear_fd", clear_fd);
+ tls_socket_nonblocking(tls_fd);
+ DEBUG_MSG2("tls_fd", tls_fd);
+
+ ssl = SSL_new(ctx);
+ if (ssl == NULL)
+ goto err;
+ DEBUG_MSG("SSL_new");
+ if (!SSL_set_fd(ssl, tls_fd))
+ goto err;
+ rbio = SSL_get_rbio(ssl);
+ wbio = SSL_get_wbio(ssl); /* should be the same, but who cares */
+ assert(rbio != NULL);
+ assert(wbio != NULL);
+ if (client_p)
+ SSL_set_connect_state(ssl);
+ else
+ SSL_set_accept_state(ssl);
+
+ closed = 0;
+ in_handshake = 1;
+ tls_to_clear.len = 0;
+ tls_to_clear.offset = 0;
+ clear_to_tls.len = 0;
+ clear_to_tls.offset = 0;
+
+ err_def = "I/O error";
+
+ /* loop finishes as soon as we detect that one side closed;
+ * when all (program and OS) buffers have enough space,
+ * the data from the last succesful read in each direction is transferred
+ * before close */
+ do {
+ int clear_read_select = 0, clear_write_select = 0,
+ tls_read_select = 0, tls_write_select = 0,
+ progress = 0;
+ int r;
+ unsigned long num_read = BIO_number_read(rbio),
+ num_written = BIO_number_written(wbio);
+
+ DEBUG_MSG2("loop iteration", ++tls_loop_count);
+
+ if (in_handshake) {
+ DEBUG_MSG("in_handshake");
+ if (client_p)
+ r = tls_connect_attempt(ssl, &tls_write_select, &tls_read_select, &closed, &progress, &err_pref_1);
+ else
+ r = tls_accept_attempt(ssl, &tls_write_select, &tls_read_select, &closed, &progress, &err_pref_1);
+ if (r != 0) {
+ write_info(ssl, &info_fd);
+ goto err;
+ }
+ if (closed)
+ goto err_return;
+ if (!SSL_in_init(ssl)) {
+ in_handshake = 0;
+ write_info(ssl, &info_fd);
+ }
+ }
+
+ if (clear_to_tls.len != 0 && !in_handshake) {
+ assert(!closed);
+
+ r = tls_write_attempt(ssl, &clear_to_tls, &tls_write_select, &tls_read_select, &closed, &progress, &err_pref_1);
+ if (r != 0)
+ goto err;
+ if (closed) {
+ assert(progress);
+ tls_to_clear.offset = 0;
+ tls_to_clear.len = 0;
+ }
+ }
+
+ if (tls_to_clear.len != 0) {
+ assert(!closed);
+
+ r = write_attempt(clear_fd, &tls_to_clear, &clear_write_select, &closed, &progress);
+ if (r != 0)
+ goto err_return;
+ if (closed) {
+ assert(progress);
+ clear_to_tls.offset = 0;
+ clear_to_tls.len = 0;
+ }
+ }
+
+ if (!closed) {
+ if (clear_to_tls.offset + clear_to_tls.len < sizeof clear_to_tls.buf) {
+ r = read_attempt(clear_fd, &clear_to_tls, &clear_read_select, &closed, &progress);
+ if (r != 0)
+ goto err_return;
+ if (closed) {
+ r = SSL_shutdown(ssl);
+ DEBUG_MSG2("SSL_shutdown", r);
+ }
+ }
+ }
+
+ if (!closed && !in_handshake) {
+ if (tls_to_clear.offset + tls_to_clear.len < sizeof tls_to_clear.buf) {
+ r = tls_read_attempt(ssl, &tls_to_clear, &tls_write_select, &tls_read_select, &closed, &progress, &err_pref_1);
+ if (r != 0)
+ goto err;
+ if (closed) {
+ r = SSL_shutdown(ssl);
+ DEBUG_MSG2("SSL_shutdown", r);
+ }
+ }
+ }
+
+ if (!progress) {
+ DEBUG_MSG("!progress?");
+ if (num_read != BIO_number_read(rbio) || num_written != BIO_number_written(wbio))
+ progress = 1;
+
+ if (!progress) {
+ DEBUG_MSG("!progress");
+ assert(clear_read_select || tls_read_select || clear_write_select || tls_write_select);
+ tls_sockets_select(clear_read_select ? clear_fd : -1, tls_read_select ? tls_fd : -1, clear_write_select ? clear_fd : -1, tls_write_select ? tls_fd : -1, -1);
+ }
+ }
+ } while (!closed);
+ return;
+
+ err:
+ tls_openssl_errors(err_pref_1, err_pref_2, err_def, tls_child_apparg);
+ err_return:
+ return;
+}
+
+
+static int
+tls_get_error(SSL *ssl, int r, int *write_select, int *read_select, int *closed, int *progress)
+{
+ int err = SSL_get_error(ssl, r);
+
+ if (err == SSL_ERROR_NONE) {
+ assert(r > 0);
+ *progress = 1;
+ return 0;
+ }
+
+ assert(r <= 0);
+
+ switch (err) {
+ case SSL_ERROR_ZERO_RETURN:
+ assert(r == 0);
+ *closed = 1;
+ *progress = 1;
+ return 0;
+
+ case SSL_ERROR_WANT_WRITE:
+ *write_select = 1;
+ return 0;
+
+ case SSL_ERROR_WANT_READ:
+ *read_select = 1;
+ return 0;
+ }
+
+ return -1;
+}
+
+static int
+tls_connect_attempt(SSL *ssl, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref)
+{
+ int n, r;
+
+ DEBUG_MSG("tls_connect_attempt");
+ n = SSL_connect(ssl);
+ DEBUG_MSG2("SSL_connect",n);
+ r = tls_get_error(ssl, n, write_select, read_select, closed, progress);
+ if (r == -1)
+ *err_pref = " during SSL_connect";
+ return r;
+}
+
+static int
+tls_accept_attempt(SSL *ssl, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref)
+{
+ int n, r;
+
+ DEBUG_MSG("tls_accept_attempt");
+ n = SSL_accept(ssl);
+ DEBUG_MSG2("SSL_accept",n);
+ r = tls_get_error(ssl, n, write_select, read_select, closed, progress);
+ if (r == -1)
+ *err_pref = " during SSL_accept";
+ return r;
+}
+
+static int
+tls_write_attempt(SSL *ssl, struct tunnelbuf *buf, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref)
+{
+ int n, r;
+
+ DEBUG_MSG("tls_write_attempt");
+ n = SSL_write(ssl, buf->buf + buf->offset, buf->len);
+ DEBUG_MSG2("SSL_write",n);
+ r = tls_get_error(ssl, n, write_select, read_select, closed, progress);
+ if (n > 0) {
+ buf->len -= n;
+ assert(buf->len >= 0);
+ if (buf->len == 0)
+ buf->offset = 0;
+ else
+ buf->offset += n;
+ }
+ if (r == -1)
+ *err_pref = " during SSL_write";
+ return r;
+}
+
+static int
+tls_read_attempt(SSL *ssl, struct tunnelbuf *buf, int *write_select, int *read_select, int *closed, int *progress, const char **err_pref)
+{
+ int n, r;
+ size_t total;
+
+ DEBUG_MSG("tls_read_attempt");
+ total = buf->offset + buf->len;
+ assert(total < sizeof buf->buf);
+ n = SSL_read(ssl, buf->buf + total, (sizeof buf->buf) - total);
+ DEBUG_MSG2("SSL_read",n);
+ r = tls_get_error(ssl, n, write_select, read_select, closed, progress);
+ if (n > 0) {
+ buf->len += n;
+ assert(buf->offset + buf->len <= sizeof buf->buf);
+ }
+ if (r == -1)
+ *err_pref = " during SSL_read";
+ return r;
+}
+
+static int
+get_error(int r, int *select, int *closed, int *progress)
+{
+ if (r >= 0) {
+ *progress = 1;
+ if (r == 0)
+ *closed = 1;
+ return 0;
+ } else {
+ assert(r == -1);
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ *select = 1;
+ return 0;
+ } else if (errno == EPIPE) {
+ *progress = 1;
+ *closed = 1;
+ return 0;
+ } else
+ return -1;
+ }
+}
+
+static int write_attempt(int fd, struct tunnelbuf *buf, int *select, int *closed, int *progress)
+{
+ int n, r;
+
+ DEBUG_MSG("write_attempt");
+ n = write(fd, buf->buf + buf->offset, buf->len);
+ DEBUG_MSG2("write",n);
+ r = get_error(n, select, closed, progress);
+ if (n > 0) {
+ buf->len -= n;
+ assert(buf->len >= 0);
+ if (buf->len == 0)
+ buf->offset = 0;
+ else
+ buf->offset += n;
+ }
+ if (r == -1)
+ tls_errprintf(1, tls_child_apparg, "write error: %s\n", strerror(errno));
+ return r;
+}
+
+static int
+read_attempt(int fd, struct tunnelbuf *buf, int *select, int *closed, int *progress)
+{
+ int n, r;
+ size_t total;
+
+ DEBUG_MSG("read_attempt");
+ total = buf->offset + buf->len;
+ assert(total < sizeof buf->buf);
+ n = read(fd, buf->buf + total, (sizeof buf->buf) - total);
+ DEBUG_MSG2("read",n);
+ r = get_error(n, select, closed, progress);
+ if (n > 0) {
+ buf->len += n;
+ assert(buf->offset + buf->len <= sizeof buf->buf);
+ }
+ if (r == -1)
+ tls_errprintf(1, tls_child_apparg, "read error: %s\n", strerror(errno));
+ return r;
+}
projects / openssl.git / commitdiff