+++ /dev/null
-// Copyright (c) 1996-2022 by the citadel.org team
-//
-// This program is open source software. You can redistribute it and/or
-// modify it under the terms of the GNU General Public License, version 3.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU General Public License for more details.
-
-#include "sysdep.h"
-#ifdef HAVE_OPENSSL
-
-#include "webcit.h"
-#include "webserver.h"
-
-
-SSL_CTX *ssl_ctx; // Global SSL context
-char key_file[PATH_MAX] = "";
-char cert_file[PATH_MAX] = "";
-char *ssl_cipher_list = DEFAULT_SSL_CIPHER_LIST;
-
-pthread_key_t ThreadSSL; // Per-thread SSL context
-
-
-// Set the private key and certificate chain for the global SSL Context.
-// This is called during initialization, and can be called again later if the certificate changes.
-void bind_to_key_and_certificate(void) {
-
- SSL_CTX *old_ctx, *new_ctx;
-
- if (IsEmptyStr(key_file)) {
- snprintf(key_file, sizeof key_file, "%s/keys/citadel.key", ctdl_dir);
- }
- if (IsEmptyStr(cert_file)) {
- snprintf(cert_file, sizeof key_file, "%s/keys/citadel.cer", ctdl_dir);
- }
-
- if (!(new_ctx = SSL_CTX_new(SSLv23_server_method()))) {
- syslog(LOG_WARNING, "SSL_CTX_new failed: %s", ERR_reason_error_string(ERR_get_error()));
- return;
- }
-
- syslog(LOG_INFO, "Requesting cipher list: %s", ssl_cipher_list);
- if (!(SSL_CTX_set_cipher_list(new_ctx, ssl_cipher_list))) {
- syslog(LOG_WARNING, "SSL_CTX_set_cipher_list failed: %s", ERR_reason_error_string(ERR_get_error()));
- return;
- }
-
- syslog(LOG_DEBUG, "crypto: [re]installing key \"%s\" and certificate \"%s\"", key_file, cert_file);
-
- SSL_CTX_use_certificate_chain_file(new_ctx, cert_file);
- SSL_CTX_use_PrivateKey_file(new_ctx, key_file, SSL_FILETYPE_PEM);
-
- if ( !SSL_CTX_check_private_key(new_ctx) ) {
- syslog(LOG_WARNING, "crypto: cannot install certificate: %s", ERR_reason_error_string(ERR_get_error()));
- }
-
- old_ctx = ssl_ctx;
- ssl_ctx = new_ctx;
- sleep(1);
- SSL_CTX_free(old_ctx);
-}
-
-
-// initialize ssl engine, load certs and initialize openssl internals
-void init_ssl(void) {
-
- // Initialize the OpenSSL library
- SSL_load_error_strings();
- ERR_load_crypto_strings();
- OpenSSL_add_all_algorithms();
- SSL_library_init();
-
- // Now try to bind to the key and certificate.
- bind_to_key_and_certificate();
-}
-
-
-// Check the modification time of the key and certificate -- reload if either one changed
-void update_key_and_cert_if_needed(void) {
- static time_t previous_mtime = 0;
- struct stat keystat;
- struct stat certstat;
-
- if (stat(key_file, &keystat) != 0) {
- syslog(LOG_ERR, "%s: %s", key_file, strerror(errno));
- return;
- }
- if (stat(cert_file, &certstat) != 0) {
- syslog(LOG_ERR, "%s: %s", cert_file, strerror(errno));
- return;
- }
-
- if ((keystat.st_mtime + certstat.st_mtime) != previous_mtime) {
- bind_to_key_and_certificate();
- previous_mtime = keystat.st_mtime + certstat.st_mtime;
- }
-}
-
-
-// starts SSL/TLS encryption for the current session.
-int starttls(int sock) {
- SSL *newssl;
- int retval, bits, alg_bits;
-
- // Check the modification time of the key and certificate -- reload if they changed
- update_key_and_cert_if_needed();
-
- // SSL is a thread-specific thing, I think.
- pthread_setspecific(ThreadSSL, NULL);
-
- if (!ssl_ctx) {
- return(1);
- }
- if (!(newssl = SSL_new(ssl_ctx))) {
- syslog(LOG_WARNING, "SSL_new failed: %s", ERR_reason_error_string(ERR_get_error()));
- return(2);
- }
- if (!(SSL_set_fd(newssl, sock))) {
- syslog(LOG_WARNING, "SSL_set_fd failed: %s", ERR_reason_error_string(ERR_get_error()));
- SSL_free(newssl);
- return(3);
- }
- retval = SSL_accept(newssl);
- if (retval < 1) {
- // Can't notify the client of an error here; they will
- // discover the problem at the SSL layer and should
- // revert to unencrypted communications.
- long errval;
- const char *ssl_error_reason = NULL;
-
- errval = SSL_get_error(newssl, retval);
- ssl_error_reason = ERR_reason_error_string(ERR_get_error());
- if (ssl_error_reason == NULL) {
- syslog(LOG_WARNING, "first SSL_accept failed: errval=%ld, retval=%d %s", errval, retval, strerror(errval));
- }
- else {
- syslog(LOG_WARNING, "first SSL_accept failed: %s", ssl_error_reason);
- }
- }
- else {
- syslog(LOG_INFO, "SSL_accept success");
- }
- BIO_set_close(SSL_get_rbio(newssl), BIO_NOCLOSE);
- bits = SSL_CIPHER_get_bits(SSL_get_current_cipher(newssl), &alg_bits);
- syslog(LOG_INFO, "SSL/TLS using %s on %s (%d of %d bits)",
- SSL_CIPHER_get_name(SSL_get_current_cipher(newssl)),
- SSL_CIPHER_get_version(SSL_get_current_cipher(newssl)),
- bits, alg_bits);
-
- pthread_setspecific(ThreadSSL, newssl);
- syslog(LOG_INFO, "SSL started");
- return(0);
-}
-
-
-// shuts down the TLS connection
-//
-// WARNING: This may make your session vulnerable to a known plaintext
-// attack in the current implmentation.
-void endtls(void) {
-
- if (THREADSSL == NULL) {
- return;
- }
-
- syslog(LOG_INFO, "Ending SSL/TLS");
- SSL_shutdown(THREADSSL);
- SSL_get_SSL_CTX(THREADSSL);
- SSL_free(THREADSSL);
- pthread_setspecific(ThreadSSL, NULL);
-}
-
-
-// Send binary data to the client encrypted.
-int client_write_ssl(const StrBuf *Buf) {
- const char *buf;
- int retval;
- int nremain;
- long nbytes;
- char junk[1];
-
- if (THREADSSL == NULL) return -1;
-
- nbytes = nremain = StrLength(Buf);
- buf = ChrPtr(Buf);
-
- while (nremain > 0) {
- if (SSL_want_write(THREADSSL)) {
- if ((SSL_read(THREADSSL, junk, 0)) < 1) {
- syslog(LOG_WARNING, "SSL_read in client_write: %s", ERR_reason_error_string(ERR_get_error()));
- }
- }
- retval = SSL_write(THREADSSL, &buf[nbytes - nremain], nremain);
- if (retval < 1) {
- long errval;
-
- errval = SSL_get_error(THREADSSL, retval);
- if (errval == SSL_ERROR_WANT_READ || errval == SSL_ERROR_WANT_WRITE) {
- sleeeeeeeeeep(1);
- continue;
- }
- syslog(LOG_WARNING, "SSL_write: %s", ERR_reason_error_string(ERR_get_error()));
- if (retval == -1) {
- syslog(LOG_WARNING, "errno is %d\n", errno);
- }
- endtls();
- return -1;
- }
- nremain -= retval;
- }
- return 0;
-}
-
-
-// read data from the encrypted layer.
-int client_read_sslbuffer(StrBuf *buf, int timeout) {
- char sbuf[16384]; // OpenSSL communicates in 16k blocks, so let's speak its native tongue.
- int rlen;
- char junk[1];
- SSL *pssl = THREADSSL;
-
- if (pssl == NULL) return(-1);
-
- while (1) {
- if (SSL_want_read(pssl)) {
- if ((SSL_write(pssl, junk, 0)) < 1) {
- syslog(LOG_WARNING, "SSL_write in client_read");
- }
- }
- rlen = SSL_read(pssl, sbuf, sizeof(sbuf));
- if (rlen < 1) {
- long errval;
-
- errval = SSL_get_error(pssl, rlen);
- if (errval == SSL_ERROR_WANT_READ || errval == SSL_ERROR_WANT_WRITE) {
- sleeeeeeeeeep(1);
- continue;
- }
- syslog(LOG_WARNING, "SSL_read in client_read: %s", ERR_reason_error_string(ERR_get_error()));
- endtls();
- return (-1);
- }
- StrBufAppendBufPlain(buf, sbuf, rlen, 0);
- return rlen;
- }
- return (0);
-}
-
-#endif /* HAVE_OPENSSL */
projects / citadel.git / blobdiff