stream: Gather streams to src/streams

1 files changed, 657 insertions, 0 deletions

diff --git a/src/streams/openssl.c b/src/streams/openssl.c
new file mode 100644
index 000000000..550b4e10b
--- /dev/null
+++ b/src/streams/openssl.c
@@ -0,0 +1,657 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "streams/openssl.h"
+
+#ifdef GIT_OPENSSL
+
+#include <ctype.h>
+
+#include "global.h"
+#include "posix.h"
+#include "stream.h"
+#include "streams/socket.h"
+#include "netops.h"
+#include "git2/transport.h"
+#include "git2/sys/openssl.h"
+
+#ifdef GIT_CURL
+# include "streams/curl.h"
+#endif
+
+#ifndef GIT_WIN32
+# include <sys/types.h>
+# include <sys/socket.h>
+# include <netinet/in.h>
+#endif
+
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <openssl/x509v3.h>
+#include <openssl/bio.h>
+
+SSL_CTX *git__ssl_ctx;
+
+#define GIT_SSL_DEFAULT_CIPHERS "ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-DSS-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA:DHE-DSS-AES128-SHA256:DHE-DSS-AES256-SHA256:DHE-DSS-AES128-SHA:DHE-DSS-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA"
+
+#if defined(GIT_THREADS) && OPENSSL_VERSION_NUMBER < 0x10100000L
+
+static git_mutex *openssl_locks;
+
+static void openssl_locking_function(
+	int mode, int n, const char *file, int line)
+{
+	int lock;
+
+	GIT_UNUSED(file);
+	GIT_UNUSED(line);
+
+	lock = mode & CRYPTO_LOCK;
+
+	if (lock) {
+		git_mutex_lock(&openssl_locks[n]);
+	} else {
+		git_mutex_unlock(&openssl_locks[n]);
+	}
+}
+
+static void shutdown_ssl_locking(void)
+{
+	int num_locks, i;
+
+	num_locks = CRYPTO_num_locks();
+	CRYPTO_set_locking_callback(NULL);
+
+	for (i = 0; i < num_locks; ++i)
+		git_mutex_free(&openssl_locks[i]);
+	git__free(openssl_locks);
+}
+
+#endif /* GIT_THREADS && OPENSSL_VERSION_NUMBER < 0x10100000L */
+
+static BIO_METHOD *git_stream_bio_method;
+static int init_bio_method(void);
+
+/**
+ * This function aims to clean-up the SSL context which
+ * we allocated.
+ */
+static void shutdown_ssl(void)
+{
+	if (git_stream_bio_method) {
+		BIO_meth_free(git_stream_bio_method);
+		git_stream_bio_method = NULL;
+	}
+
+	if (git__ssl_ctx) {
+		SSL_CTX_free(git__ssl_ctx);
+		git__ssl_ctx = NULL;
+	}
+}
+
+int git_openssl_stream_global_init(void)
+{
+#ifdef GIT_OPENSSL
+	long ssl_opts = SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3;
+	const char *ciphers = git_libgit2__ssl_ciphers();
+
+	/* Older OpenSSL and MacOS OpenSSL doesn't have this */
+#ifdef SSL_OP_NO_COMPRESSION
+	ssl_opts |= SSL_OP_NO_COMPRESSION;
+#endif
+
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+	SSL_load_error_strings();
+	OpenSSL_add_ssl_algorithms();
+#else
+	OPENSSL_init_ssl(0, NULL);
+#endif
+
+	/*
+	 * Load SSLv{2,3} and TLSv1 so that we can talk with servers
+	 * which use the SSL hellos, which are often used for
+	 * compatibility. We then disable SSL so we only allow OpenSSL
+	 * to speak TLSv1 to perform the encryption itself.
+	 */
+	git__ssl_ctx = SSL_CTX_new(SSLv23_method());
+	SSL_CTX_set_options(git__ssl_ctx, ssl_opts);
+	SSL_CTX_set_mode(git__ssl_ctx, SSL_MODE_AUTO_RETRY);
+	SSL_CTX_set_verify(git__ssl_ctx, SSL_VERIFY_NONE, NULL);
+	if (!SSL_CTX_set_default_verify_paths(git__ssl_ctx)) {
+		SSL_CTX_free(git__ssl_ctx);
+		git__ssl_ctx = NULL;
+		return -1;
+	}
+
+	if (!ciphers) {
+		ciphers = GIT_SSL_DEFAULT_CIPHERS;
+	}
+
+	if(!SSL_CTX_set_cipher_list(git__ssl_ctx, ciphers)) {
+		SSL_CTX_free(git__ssl_ctx);
+		git__ssl_ctx = NULL;
+		return -1;
+	}
+
+	if (init_bio_method() < 0) {
+		SSL_CTX_free(git__ssl_ctx);
+		git__ssl_ctx = NULL;
+		return -1;
+	}
+
+#endif
+
+	git__on_shutdown(shutdown_ssl);
+
+	return 0;
+}
+
+int git_openssl_set_locking(void)
+{
+#if defined(GIT_THREADS) && OPENSSL_VERSION_NUMBER < 0x10100000L
+	int num_locks, i;
+
+	num_locks = CRYPTO_num_locks();
+	openssl_locks = git__calloc(num_locks, sizeof(git_mutex));
+	GITERR_CHECK_ALLOC(openssl_locks);
+
+	for (i = 0; i < num_locks; i++) {
+		if (git_mutex_init(&openssl_locks[i]) != 0) {
+			giterr_set(GITERR_SSL, "failed to initialize openssl locks");
+			return -1;
+		}
+	}
+
+	CRYPTO_set_locking_callback(openssl_locking_function);
+	git__on_shutdown(shutdown_ssl_locking);
+	return 0;
+#elif OPENSSL_VERSION_NUMBER >= 0x10100000L
+	return 0;
+#else
+	giterr_set(GITERR_THREAD, "libgit2 was not built with threads");
+	return -1;
+#endif
+}
+
+
+static int bio_create(BIO *b)
+{
+	BIO_set_init(b, 1);
+	BIO_set_data(b, NULL);
+
+	return 1;
+}
+
+static int bio_destroy(BIO *b)
+{
+	if (!b)
+		return 0;
+
+	BIO_set_data(b, NULL);
+
+	return 1;
+}
+
+static int bio_read(BIO *b, char *buf, int len)
+{
+	git_stream *io = (git_stream *) BIO_get_data(b);
+
+	return (int) git_stream_read(io, buf, len);
+}
+
+static int bio_write(BIO *b, const char *buf, int len)
+{
+	git_stream *io = (git_stream *) BIO_get_data(b);
+
+	return (int) git_stream_write(io, buf, len, 0);
+}
+
+static long bio_ctrl(BIO *b, int cmd, long num, void *ptr)
+{
+	GIT_UNUSED(b);
+	GIT_UNUSED(num);
+	GIT_UNUSED(ptr);
+
+	if (cmd == BIO_CTRL_FLUSH)
+		return 1;
+
+	return 0;
+}
+
+static int bio_gets(BIO *b, char *buf, int len)
+{
+	GIT_UNUSED(b);
+	GIT_UNUSED(buf);
+	GIT_UNUSED(len);
+	return -1;
+}
+
+static int bio_puts(BIO *b, const char *str)
+{
+	return bio_write(b, str, strlen(str));
+}
+
+static int init_bio_method(void)
+{
+	/* Set up the BIO_METHOD we use for wrapping our own stream implementations */
+	git_stream_bio_method = BIO_meth_new(BIO_TYPE_SOURCE_SINK | BIO_get_new_index(), "git_stream");
+	GITERR_CHECK_ALLOC(git_stream_bio_method);
+
+	BIO_meth_set_write(git_stream_bio_method, bio_write);
+	BIO_meth_set_read(git_stream_bio_method, bio_read);
+	BIO_meth_set_puts(git_stream_bio_method, bio_puts);
+	BIO_meth_set_gets(git_stream_bio_method, bio_gets);
+	BIO_meth_set_ctrl(git_stream_bio_method, bio_ctrl);
+	BIO_meth_set_create(git_stream_bio_method, bio_create);
+	BIO_meth_set_destroy(git_stream_bio_method, bio_destroy);
+
+	return 0;
+}
+
+static int ssl_set_error(SSL *ssl, int error)
+{
+	int err;
+	unsigned long e;
+
+	err = SSL_get_error(ssl, error);
+
+	assert(err != SSL_ERROR_WANT_READ);
+	assert(err != SSL_ERROR_WANT_WRITE);
+
+	switch (err) {
+	case SSL_ERROR_WANT_CONNECT:
+	case SSL_ERROR_WANT_ACCEPT:
+		giterr_set(GITERR_NET, "SSL error: connection failure");
+		break;
+	case SSL_ERROR_WANT_X509_LOOKUP:
+		giterr_set(GITERR_NET, "SSL error: x509 error");
+		break;
+	case SSL_ERROR_SYSCALL:
+		e = ERR_get_error();
+		if (e > 0) {
+			giterr_set(GITERR_NET, "SSL error: %s",
+					ERR_error_string(e, NULL));
+			break;
+		} else if (error < 0) {
+			giterr_set(GITERR_OS, "SSL error: syscall failure");
+			break;
+		}
+		giterr_set(GITERR_NET, "SSL error: received early EOF");
+		return GIT_EEOF;
+		break;
+	case SSL_ERROR_SSL:
+		e = ERR_get_error();
+		giterr_set(GITERR_NET, "SSL error: %s",
+				ERR_error_string(e, NULL));
+		break;
+	case SSL_ERROR_NONE:
+	case SSL_ERROR_ZERO_RETURN:
+	default:
+		giterr_set(GITERR_NET, "SSL error: unknown error");
+		break;
+	}
+	return -1;
+}
+
+static int ssl_teardown(SSL *ssl)
+{
+	int ret;
+
+	ret = SSL_shutdown(ssl);
+	if (ret < 0)
+		ret = ssl_set_error(ssl, ret);
+	else
+		ret = 0;
+
+	return ret;
+}
+
+static int check_host_name(const char *name, const char *host)
+{
+	if (!strcasecmp(name, host))
+		return 0;
+
+	if (gitno__match_host(name, host) < 0)
+		return -1;
+
+	return 0;
+}
+
+static int verify_server_cert(SSL *ssl, const char *host)
+{
+	X509 *cert;
+	X509_NAME *peer_name;
+	ASN1_STRING *str;
+	unsigned char *peer_cn = NULL;
+	int matched = -1, type = GEN_DNS;
+	GENERAL_NAMES *alts;
+	struct in6_addr addr6;
+	struct in_addr addr4;
+	void *addr;
+	int i = -1,j;
+
+	if (SSL_get_verify_result(ssl) != X509_V_OK) {
+		giterr_set(GITERR_SSL, "the SSL certificate is invalid");
+		return GIT_ECERTIFICATE;
+	}
+
+	/* Try to parse the host as an IP address to see if it is */
+	if (p_inet_pton(AF_INET, host, &addr4)) {
+		type = GEN_IPADD;
+		addr = &addr4;
+	} else {
+		if(p_inet_pton(AF_INET6, host, &addr6)) {
+			type = GEN_IPADD;
+			addr = &addr6;
+		}
+	}
+
+
+	cert = SSL_get_peer_certificate(ssl);
+	if (!cert) {
+		giterr_set(GITERR_SSL, "the server did not provide a certificate");
+		return -1;
+	}
+
+	/* Check the alternative names */
+	alts = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
+	if (alts) {
+		int num;
+
+		num = sk_GENERAL_NAME_num(alts);
+		for (i = 0; i < num && matched != 1; i++) {
+			const GENERAL_NAME *gn = sk_GENERAL_NAME_value(alts, i);
+			const char *name = (char *) ASN1_STRING_get0_data(gn->d.ia5);
+			size_t namelen = (size_t) ASN1_STRING_length(gn->d.ia5);
+
+			/* Skip any names of a type we're not looking for */
+			if (gn->type != type)
+				continue;
+
+			if (type == GEN_DNS) {
+				/* If it contains embedded NULs, don't even try */
+				if (memchr(name, '\0', namelen))
+					continue;
+
+				if (check_host_name(name, host) < 0)
+					matched = 0;
+				else
+					matched = 1;
+			} else if (type == GEN_IPADD) {
+				/* Here name isn't so much a name but a binary representation of the IP */
+				matched = !!memcmp(name, addr, namelen);
+			}
+		}
+	}
+	GENERAL_NAMES_free(alts);
+
+	if (matched == 0)
+		goto cert_fail_name;
+
+	if (matched == 1)
+		return 0;
+
+	/* If no alternative names are available, check the common name */
+	peer_name = X509_get_subject_name(cert);
+	if (peer_name == NULL)
+		goto on_error;
+
+	if (peer_name) {
+		/* Get the index of the last CN entry */
+		while ((j = X509_NAME_get_index_by_NID(peer_name, NID_commonName, i)) >= 0)
+			i = j;
+	}
+
+	if (i < 0)
+		goto on_error;
+
+	str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(peer_name, i));
+	if (str == NULL)
+		goto on_error;
+
+	/* Work around a bug in OpenSSL whereby ASN1_STRING_to_UTF8 fails if it's already in utf-8 */
+	if (ASN1_STRING_type(str) == V_ASN1_UTF8STRING) {
+		int size = ASN1_STRING_length(str);
+
+		if (size > 0) {
+			peer_cn = OPENSSL_malloc(size + 1);
+			GITERR_CHECK_ALLOC(peer_cn);
+			memcpy(peer_cn, ASN1_STRING_get0_data(str), size);
+			peer_cn[size] = '\0';
+		} else {
+			goto cert_fail_name;
+		}
+	} else {
+		int size = ASN1_STRING_to_UTF8(&peer_cn, str);
+		GITERR_CHECK_ALLOC(peer_cn);
+		if (memchr(peer_cn, '\0', size))
+			goto cert_fail_name;
+	}
+
+	if (check_host_name((char *)peer_cn, host) < 0)
+		goto cert_fail_name;
+
+	OPENSSL_free(peer_cn);
+
+	return 0;
+
+on_error:
+	OPENSSL_free(peer_cn);
+	return ssl_set_error(ssl, 0);
+
+cert_fail_name:
+	OPENSSL_free(peer_cn);
+	giterr_set(GITERR_SSL, "hostname does not match certificate");
+	return GIT_ECERTIFICATE;
+}
+
+typedef struct {
+	git_stream parent;
+	git_stream *io;
+	bool connected;
+	char *host;
+	SSL *ssl;
+	git_cert_x509 cert_info;
+} openssl_stream;
+
+int openssl_close(git_stream *stream);
+
+int openssl_connect(git_stream *stream)
+{
+	int ret;
+	BIO *bio;
+	openssl_stream *st = (openssl_stream *) stream;
+
+	if ((ret = git_stream_connect(st->io)) < 0)
+		return ret;
+
+	st->connected = true;
+
+	bio = BIO_new(git_stream_bio_method);
+	GITERR_CHECK_ALLOC(bio);
+
+	BIO_set_data(bio, st->io);
+	SSL_set_bio(st->ssl, bio, bio);
+
+	/* specify the host in case SNI is needed */
+#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
+	SSL_set_tlsext_host_name(st->ssl, st->host);
+#endif
+
+	if ((ret = SSL_connect(st->ssl)) <= 0)
+		return ssl_set_error(st->ssl, ret);
+
+	return verify_server_cert(st->ssl, st->host);
+}
+
+int openssl_certificate(git_cert **out, git_stream *stream)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int len;
+	X509 *cert = SSL_get_peer_certificate(st->ssl);
+	unsigned char *guard, *encoded_cert;
+
+	/* Retrieve the length of the certificate first */
+	len = i2d_X509(cert, NULL);
+	if (len < 0) {
+		giterr_set(GITERR_NET, "failed to retrieve certificate information");
+		return -1;
+	}
+
+	encoded_cert = git__malloc(len);
+	GITERR_CHECK_ALLOC(encoded_cert);
+	/* i2d_X509 makes 'guard' point to just after the data */
+	guard = encoded_cert;
+
+	len = i2d_X509(cert, &guard);
+	if (len < 0) {
+		git__free(encoded_cert);
+		giterr_set(GITERR_NET, "failed to retrieve certificate information");
+		return -1;
+	}
+
+	st->cert_info.parent.cert_type = GIT_CERT_X509;
+	st->cert_info.data = encoded_cert;
+	st->cert_info.len = len;
+
+	*out = &st->cert_info.parent;
+
+	return 0;
+}
+
+static int openssl_set_proxy(git_stream *stream, const git_proxy_options *proxy_opts)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+
+	return git_stream_set_proxy(st->io, proxy_opts);
+}
+
+ssize_t openssl_write(git_stream *stream, const char *data, size_t len, int flags)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+
+	GIT_UNUSED(flags);
+
+	if ((ret = SSL_write(st->ssl, data, len)) <= 0) {
+		return ssl_set_error(st->ssl, ret);
+	}
+
+	return ret;
+}
+
+ssize_t openssl_read(git_stream *stream, void *data, size_t len)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+
+	if ((ret = SSL_read(st->ssl, data, len)) <= 0)
+		return ssl_set_error(st->ssl, ret);
+
+	return ret;
+}
+
+int openssl_close(git_stream *stream)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+
+	if (st->connected && (ret = ssl_teardown(st->ssl)) < 0)
+		return -1;
+
+	st->connected = false;
+
+	return git_stream_close(st->io);
+}
+
+void openssl_free(git_stream *stream)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+
+	SSL_free(st->ssl);
+	git__free(st->host);
+	git__free(st->cert_info.data);
+	git_stream_free(st->io);
+	git__free(st);
+}
+
+int git_openssl_stream_new(git_stream **out, const char *host, const char *port)
+{
+	int error;
+	openssl_stream *st;
+
+	st = git__calloc(1, sizeof(openssl_stream));
+	GITERR_CHECK_ALLOC(st);
+
+	st->io = NULL;
+#ifdef GIT_CURL
+	error = git_curl_stream_new(&st->io, host, port);
+#else
+	error = git_socket_stream_new(&st->io, host, port);
+#endif
+
+	if (error < 0)
+		goto out_err;
+
+	st->ssl = SSL_new(git__ssl_ctx);
+	if (st->ssl == NULL) {
+		giterr_set(GITERR_SSL, "failed to create ssl object");
+		error = -1;
+		goto out_err;
+	}
+
+	st->host = git__strdup(host);
+	GITERR_CHECK_ALLOC(st->host);
+
+	st->parent.version = GIT_STREAM_VERSION;
+	st->parent.encrypted = 1;
+	st->parent.proxy_support = git_stream_supports_proxy(st->io);
+	st->parent.connect = openssl_connect;
+	st->parent.certificate = openssl_certificate;
+	st->parent.set_proxy = openssl_set_proxy;
+	st->parent.read = openssl_read;
+	st->parent.write = openssl_write;
+	st->parent.close = openssl_close;
+	st->parent.free = openssl_free;
+
+	*out = (git_stream *) st;
+	return 0;
+
+out_err:
+	git_stream_free(st->io);
+	git__free(st);
+
+	return error;
+}
+
+#else
+
+#include "stream.h"
+#include "git2/sys/openssl.h"
+
+int git_openssl_stream_global_init(void)
+{
+	return 0;
+}
+
+int git_openssl_set_locking(void)
+{
+	giterr_set(GITERR_SSL, "libgit2 was not built with OpenSSL support");
+	return -1;
+}
+
+int git_openssl_stream_new(git_stream **out, const char *host, const char *port)
+{
+	GIT_UNUSED(out);
+	GIT_UNUSED(host);
+	GIT_UNUSED(port);
+
+	giterr_set(GITERR_SSL, "openssl is not supported in this version");
+	return -1;
+}
+
+#endif