libpcap: Update to 1.10.3

Prior to this MFC, the stable/13 libpcap was at version 1.9.1, which was
released over five years ago.  Several CVEs have been identified in that
version.  For a detailed list, see
https://www.tcpdump.org/public-cve-list.txt.

Reviewed by:	kp (pf changes)
Sponsored by:	The FreeBSD Foundation

(cherry picked from commit 6d1c946e916845d01062e146aad5395410da1e54)
(cherry picked from commit 0c59e0b4e5817f139ce28486085b2f196351c7a3)
(cherry picked from commit 512c553671bef26e93342d4ae1ec5f60d8ae112b)
(cherry picked from commit 6f9cba8f8b5efd16249633e52483ea351876b67b)
(cherry picked from commit 437f05885047c533cadf15b564729cfd0273d2fe)

Commit 437f05885047c533cadf15b564729cfd0273d2fe has been adapted to only
include the changes for the libpcap 1.10.3 update.

1 files changed, 239 insertions, 0 deletions

diff --git a/contrib/libpcap/sslutils.c b/contrib/libpcap/sslutils.c
new file mode 100644
index 000000000000..7274cc34c580
--- /dev/null
+++ b/contrib/libpcap/sslutils.c
@@ -0,0 +1,239 @@
+/*
+ * Copyright (c) 2002 - 2003
+ * NetGroup, Politecnico di Torino (Italy)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name of the Politecnico di Torino nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS 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 THE COPYRIGHT
+ * OWNER OR 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.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#ifdef HAVE_OPENSSL
+#include <stdlib.h>
+
+#include "portability.h"
+
+#include "sslutils.h"
+
+static const char *ssl_keyfile = "";   //!< file containing the private key in PEM format
+static const char *ssl_certfile = "";  //!< file containing the server's certificate in PEM format
+static const char *ssl_rootfile = "";  //!< file containing the list of CAs trusted by the client
+// TODO: a way to set ssl_rootfile from the command line, or an envvar?
+
+// TODO: lock?
+static SSL_CTX *ctx;
+
+void ssl_set_certfile(const char *certfile)
+{
+	ssl_certfile = certfile;
+}
+
+void ssl_set_keyfile(const char *keyfile)
+{
+	ssl_keyfile = keyfile;
+}
+
+int ssl_init_once(int is_server, int enable_compression, char *errbuf, size_t errbuflen)
+{
+	static int inited = 0;
+	if (inited) return 0;
+
+	SSL_library_init();
+	SSL_load_error_strings();
+	OpenSSL_add_ssl_algorithms();
+	if (enable_compression)
+		SSL_COMP_get_compression_methods();
+
+	SSL_METHOD const *meth =
+	    is_server ? SSLv23_server_method() : SSLv23_client_method();
+	ctx = SSL_CTX_new(meth);
+	if (! ctx)
+	{
+		snprintf(errbuf, errbuflen, "Cannot get a new SSL context: %s", ERR_error_string(ERR_get_error(), NULL));
+		goto die;
+	}
+
+	SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY);
+
+	if (is_server)
+	{
+		char const *certfile = ssl_certfile[0] ? ssl_certfile : "cert.pem";
+		if (1 != SSL_CTX_use_certificate_file(ctx, certfile, SSL_FILETYPE_PEM))
+		{
+			snprintf(errbuf, errbuflen, "Cannot read certificate file %s: %s", certfile, ERR_error_string(ERR_get_error(), NULL));
+			goto die;
+		}
+
+		char const *keyfile = ssl_keyfile[0] ? ssl_keyfile : "key.pem";
+		if (1 != SSL_CTX_use_PrivateKey_file(ctx, keyfile, SSL_FILETYPE_PEM))
+		{
+			snprintf(errbuf, errbuflen, "Cannot read private key file %s: %s", keyfile, ERR_error_string(ERR_get_error(), NULL));
+			goto die;
+		}
+	}
+	else
+	{
+		if (ssl_rootfile[0])
+		{
+			if (! SSL_CTX_load_verify_locations(ctx, ssl_rootfile, 0))
+			{
+				snprintf(errbuf, errbuflen, "Cannot read CA list from %s", ssl_rootfile);
+				goto die;
+			}
+		}
+		else
+		{
+			SSL_CTX_set_verify(ctx, SSL_VERIFY_NONE, NULL);
+		}
+	}
+
+#if 0
+	if (! RAND_load_file(RANDOM, 1024*1024))
+	{
+		snprintf(errbuf, errbuflen, "Cannot init random");
+		goto die;
+	}
+
+	if (is_server)
+	{
+		SSL_CTX_set_session_id_context(ctx, (void *)&s_server_session_id_context, sizeof(s_server_session_id_context));
+	}
+#endif
+
+	inited = 1;
+	return 0;
+
+die:
+	return -1;
+}
+
+SSL *ssl_promotion(int is_server, SOCKET s, char *errbuf, size_t errbuflen)
+{
+	if (ssl_init_once(is_server, 1, errbuf, errbuflen) < 0) {
+		return NULL;
+	}
+
+	SSL *ssl = SSL_new(ctx); // TODO: also a DTLS context
+	SSL_set_fd(ssl, (int)s);
+
+	if (is_server) {
+		if (SSL_accept(ssl) <= 0) {
+			snprintf(errbuf, errbuflen, "SSL_accept(): %s",
+					ERR_error_string(ERR_get_error(), NULL));
+			return NULL;
+		}
+	} else {
+		if (SSL_connect(ssl) <= 0) {
+			snprintf(errbuf, errbuflen, "SSL_connect(): %s",
+					ERR_error_string(ERR_get_error(), NULL));
+			return NULL;
+		}
+	}
+
+	return ssl;
+}
+
+// Finish using an SSL handle; shut down the connection and free the
+// handle.
+void ssl_finish(SSL *ssl)
+{
+	//
+	// We won't be using this again, so we can just send the
+	// shutdown alert and free up the handle, and have our
+	// caller close the socket.
+	//
+	// XXX - presumably, if the connection is shut down on
+	// our side, either our peer won't have a problem sending
+	// their shutdown alert or will not treat such a problem
+	// as an error.  If this causes errors to be reported,
+	// fix that as appropriate.
+	//
+	SSL_shutdown(ssl);
+	SSL_free(ssl);
+}
+
+// Same return value as sock_send:
+// 0 on OK, -1 on error but closed connection (-2).
+int ssl_send(SSL *ssl, char const *buffer, int size, char *errbuf, size_t errbuflen)
+{
+	int status = SSL_write(ssl, buffer, size);
+	if (status > 0)
+	{
+		// "SSL_write() will only return with success, when the complete contents (...) has been written."
+		return 0;
+	}
+	else
+	{
+		int ssl_err = SSL_get_error(ssl, status); // TODO: does it pop the error?
+		if (ssl_err == SSL_ERROR_ZERO_RETURN)
+		{
+			return -2;
+		}
+		else if (ssl_err == SSL_ERROR_SYSCALL)
+		{
+#ifndef _WIN32
+			if (errno == ECONNRESET || errno == EPIPE) return -2;
+#endif
+		}
+		snprintf(errbuf, errbuflen, "SSL_write(): %s",
+		    ERR_error_string(ERR_get_error(), NULL));
+		return -1;
+	}
+}
+
+// Returns the number of bytes read, or -1 on syserror, or -2 on SSL error.
+int ssl_recv(SSL *ssl, char *buffer, int size, char *errbuf, size_t errbuflen)
+{
+	int status = SSL_read(ssl, buffer, size);
+	if (status <= 0)
+	{
+		int ssl_err = SSL_get_error(ssl, status);
+		if (ssl_err == SSL_ERROR_ZERO_RETURN)
+		{
+			return 0;
+		}
+		else if (ssl_err == SSL_ERROR_SYSCALL)
+		{
+			return -1;
+		}
+		else
+		{
+			// Should not happen
+			snprintf(errbuf, errbuflen, "SSL_read(): %s",
+			    ERR_error_string(ERR_get_error(), NULL));
+			return -2;
+		}
+	}
+	else
+	{
+		return status;
+	}
+}
+
+#endif // HAVE_OPENSSL