Merge pull request #2678 from libgit2/cmn/io-stream

Introduce stackable IO streams

include/git2/sys/stream.h

+/*
+ * 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.
+ */
+#ifndef INCLUDE_sys_git_stream_h__
+#define INCLUDE_sys_git_stream_h__
+
+#include "git2/common.h"
+#include "git2/types.h"
+
+GIT_BEGIN_DECL
+
+#define GIT_STREAM_VERSION 1
+
+/**
+ * Every stream must have this struct as its first element, so the
+ * API can talk to it. You'd define your stream as
+ *
+ *     struct my_stream {
+ *             git_stream parent;
+ *             ...
+ *     }
+ *
+ * and fill the functions
+ */
+typedef struct git_stream {
+	int version;
+
+	int encrypted;
+	int (*connect)(struct git_stream *);
+	int (*certificate)(git_cert **, struct git_stream *);
+	ssize_t (*read)(struct git_stream *, void *, size_t);
+	ssize_t (*write)(struct git_stream *, const char *, size_t, int);
+	int (*close)(struct git_stream *);
+	void (*free)(struct git_stream *);
+} git_stream;
+
+#endif

src/netops.h

@@ -9,6 +9,7 @@
 
 #include "posix.h"
 #include "common.h"
+#include "stream.h"
 
 #ifdef GIT_SSL
 # include <openssl/ssl.h>
@@ -32,7 +33,6 @@ typedef struct gitno_buffer {
 	char *data;
 	size_t len;
 	size_t offset;
-	gitno_socket *socket;
 	int (*recv)(struct gitno_buffer *buffer);
 	void *cb_data;
 } gitno_buffer;
@@ -56,18 +56,13 @@ enum {
  */
 int gitno__match_host(const char *pattern, const char *host);
 
-void gitno_buffer_setup(gitno_socket *t, gitno_buffer *buf, char *data, size_t len);
-void gitno_buffer_setup_callback(gitno_socket *t, gitno_buffer *buf, char *data, size_t len, int (*recv)(gitno_buffer *buf), void *cb_data);
+void gitno_buffer_setup_fromstream(git_stream *st, gitno_buffer *buf, char *data, size_t len);
+void gitno_buffer_setup_callback(gitno_buffer *buf, char *data, size_t len, int (*recv)(gitno_buffer *buf), void *cb_data);
 int gitno_recv(gitno_buffer *buf);
 
 void gitno_consume(gitno_buffer *buf, const char *ptr);
 void gitno_consume_n(gitno_buffer *buf, size_t cons);
 
-int gitno_connect(gitno_socket *socket, const char *host, const char *port, int flags);
-int gitno_send(gitno_socket *socket, const char *msg, size_t len, int flags);
-int gitno_close(gitno_socket *s);
-int gitno_select_in(gitno_buffer *buf, long int sec, long int usec);
-
 typedef struct gitno_connection_data {
 	char *host;
 	char *port;

src/openssl_stream.c

+/*
+ * 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.
+ */
+
+#ifdef GIT_SSL
+
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <openssl/x509v3.h>
+
+#include <ctype.h>
+
+#include "global.h"
+#include "posix.h"
+#include "stream.h"
+#include "socket_stream.h"
+#include "netops.h"
+#include "git2/transport.h"
+
+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\n");
+		break;
+	case SSL_ERROR_WANT_X509_LOOKUP:
+		giterr_set(GITERR_NET, "SSL error: x509 error\n");
+		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");
+		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;
+
+	SSL_free(ssl);
+	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_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_data(str), size);
+			peer_cn[size] = '\0';
+		}
+	} 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_socket_stream *socket;
+	SSL *ssl;
+	git_cert_x509 cert_info;
+} openssl_stream;
+
+int openssl_close(git_stream *stream);
+
+int openssl_connect(git_stream *stream)
+{
+	int ret;
+	openssl_stream *st = (openssl_stream *) stream;
+
+	if ((ret = git_stream_connect((git_stream *)st->socket)) < 0)
+		return ret;
+
+	if ((ret = SSL_set_fd(st->ssl, st->socket->s)) <= 0) {
+		openssl_close((git_stream *) st);
+		return ssl_set_error(st->ssl, ret);
+	}
+
+	if ((ret = SSL_connect(st->ssl)) <= 0)
+		return ssl_set_error(st->ssl, ret);
+
+	return verify_server_cert(st->ssl, st->socket->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.cert_type = GIT_CERT_X509;
+	st->cert_info.data = encoded_cert;
+	st->cert_info.len = len;
+
+	*out = (git_cert *)&st->cert_info;
+	return 0;
+}
+
+ssize_t openssl_write(git_stream *stream, const char *data, size_t len, int flags)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+	size_t off = 0;
+
+	GIT_UNUSED(flags);
+
+	while (off < len) {
+		ret = SSL_write(st->ssl, data + off, len - off);
+		if (ret <= 0 && ret != SSL_ERROR_WANT_WRITE)
+			return ssl_set_error(st->ssl, ret);
+
+		off += ret;
+	}	
+
+	return off;
+}
+
+ssize_t openssl_read(git_stream *stream, void *data, size_t len)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+
+	do {
+		ret = SSL_read(st->ssl, data, len);
+	} while (SSL_get_error(st->ssl, ret) == SSL_ERROR_WANT_READ);
+
+	if (ret < 0) {
+		ssl_set_error(st->ssl, ret);
+		return -1;
+	}
+
+	return ret;
+}
+
+int openssl_close(git_stream *stream)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+	int ret;
+
+	if ((ret = ssl_teardown(st->ssl)) < 0)
+		return -1;
+
+	return git_stream_close((git_stream *)st->socket);
+}
+
+void openssl_free(git_stream *stream)
+{
+	openssl_stream *st = (openssl_stream *) stream;
+
+	git__free(st->cert_info.data);
+	git_stream_free((git_stream *) st->socket);
+	git__free(st);
+}
+
+int git_openssl_stream_new(git_stream **out, const char *host, const char *port)
+{
+	openssl_stream *st;
+
+	st = git__calloc(1, sizeof(openssl_stream));
+	GITERR_CHECK_ALLOC(st);
+
+	if (git_socket_stream_new((git_stream **) &st->socket, host, port))
+		return -1;
+
+	st->ssl = SSL_new(git__ssl_ctx);
+	if (st->ssl == NULL) {
+		giterr_set(GITERR_SSL, "failed to create ssl object");
+		return -1;
+	}
+
+	st->parent.version = GIT_STREAM_VERSION;
+	st->parent.encrypted = 1;
+	st->parent.connect = openssl_connect;
+	st->parent.certificate = openssl_certificate;
+	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;
+}
+
+#else
+
+#include "stream.h"
+
+int git_openssl_stream_new(git_stream **out, const char *host, const char *port)
+{
+	giterr_set(GITERR_SSL, "openssl is not supported in this version");
+	return -1;
+}
+
+#endif

src/openssl_stream.h

+/*
+ * 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.
+ */
+#ifndef INCLUDE_openssl_stream_h__
+#define INCLUDE_openssl_stream_h__
+
+#include "git2/sys/stream.h"
+
+extern int git_openssl_stream_new(git_stream **out, const char *host, const char *port);
+
+#endif

src/socket_stream.c

+/*
+ * 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 "common.h"
+#include "posix.h"
+#include "netops.h"
+#include "stream.h"
+#include "socket_stream.h"
+
+#ifndef _WIN32
+#	include <sys/types.h>
+#	include <sys/socket.h>
+#	include <sys/select.h>
+#	include <sys/time.h>
+#	include <netdb.h>
+#	include <netinet/in.h>
+#       include <arpa/inet.h>
+#else
+#	include <winsock2.h>
+#	include <ws2tcpip.h>
+#	ifdef _MSC_VER
+#		pragma comment(lib, "ws2_32")
+#	endif
+#endif
+
+#ifdef GIT_WIN32
+static void net_set_error(const char *str)
+{
+	int error = WSAGetLastError();
+	char * win32_error = git_win32_get_error_message(error);
+
+	if (win32_error) {
+		giterr_set(GITERR_NET, "%s: %s", str, win32_error);
+		git__free(win32_error);
+	} else {
+		giterr_set(GITERR_NET, str);
+	}
+}
+#else
+static void net_set_error(const char *str)
+{
+	giterr_set(GITERR_NET, "%s: %s", str, strerror(errno));
+}
+#endif
+
+static int close_socket(GIT_SOCKET s)
+{
+	if (s == INVALID_SOCKET)
+		return 0;
+
+#ifdef GIT_WIN32
+	if (SOCKET_ERROR == closesocket(s))
+		return -1;
+
+	if (0 != WSACleanup()) {
+		giterr_set(GITERR_OS, "Winsock cleanup failed");
+		return -1;
+	}
+
+	return 0;
+#else
+	return close(s);
+#endif
+
+}
+
+int socket_connect(git_stream *stream)
+{
+	struct addrinfo *info = NULL, *p;
+	struct addrinfo hints;
+	git_socket_stream *st = (git_socket_stream *) stream;
+	GIT_SOCKET s = INVALID_SOCKET;
+	int ret;
+
+#ifdef GIT_WIN32
+	/* on win32, the WSA context needs to be initialized
+	 * before any socket calls can be performed */
+	WSADATA wsd;
+
+	if (WSAStartup(MAKEWORD(2,2), &wsd) != 0) {
+		giterr_set(GITERR_OS, "Winsock init failed");
+		return -1;
+	}
+
+	if (LOBYTE(wsd.wVersion) != 2 || HIBYTE(wsd.wVersion) != 2) {
+		WSACleanup();
+		giterr_set(GITERR_OS, "Winsock init failed");
+		return -1;
+	}
+#endif
+
+	memset(&hints, 0x0, sizeof(struct addrinfo));
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_family = AF_UNSPEC;
+
+	if ((ret = p_getaddrinfo(st->host, st->port, &hints, &info)) != 0) {
+		giterr_set(GITERR_NET,
+			   "Failed to resolve address for %s: %s", st->host, p_gai_strerror(ret));
+		return -1;
+	}
+
+	for (p = info; p != NULL; p = p->ai_next) {
+		s = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
+
+		if (s == INVALID_SOCKET) {
+			net_set_error("error creating socket");
+			break;
+		}
+
+		if (connect(s, p->ai_addr, (socklen_t)p->ai_addrlen) == 0)
+			break;
+
+		/* If we can't connect, try the next one */
+		close_socket(s);
+		s = INVALID_SOCKET;
+	}
+
+	/* Oops, we couldn't connect to any address */
+	if (s == INVALID_SOCKET && p == NULL) {
+		giterr_set(GITERR_OS, "Failed to connect to %s", st->host);
+		p_freeaddrinfo(info);
+		return -1;
+	}
+
+	st->s = s;
+	p_freeaddrinfo(info);
+	return 0;
+}
+
+ssize_t socket_write(git_stream *stream, const char *data, size_t len, int flags)
+{
+	ssize_t ret;
+	size_t off = 0;
+	git_socket_stream *st = (git_socket_stream *) stream;
+
+	while (off < len) {
+		errno = 0;
+		ret = p_send(st->s, data + off, len - off, flags);
+		if (ret < 0) {
+			net_set_error("Error sending data");
+			return -1;
+		}
+
+		off += ret;
+	}
+
+	return off;
+}
+
+ssize_t socket_read(git_stream *stream, void *data, size_t len)
+{
+	ssize_t ret;
+	git_socket_stream *st = (git_socket_stream *) stream;
+
+	if ((ret = p_recv(st->s, data, len, 0)) < 0)
+		net_set_error("Error receiving socket data");
+
+	return ret;
+}
+
+int socket_close(git_stream *stream)
+{
+	git_socket_stream *st = (git_socket_stream *) stream;
+	int error;
+
+	error = close_socket(st->s);
+	st->s = INVALID_SOCKET;
+
+	return error;
+}
+
+void socket_free(git_stream *stream)
+{
+	git_socket_stream *st = (git_socket_stream *) stream;
+
+	git__free(st->host);
+	git__free(st->port);
+	git__free(st);
+}
+
+int git_socket_stream_new(git_stream **out, const char *host, const char *port)
+{
+	git_socket_stream *st;
+
+	assert(out && host);
+
+	st = git__calloc(1, sizeof(git_socket_stream));
+	GITERR_CHECK_ALLOC(st);
+
+	st->host = git__strdup(host);
+	GITERR_CHECK_ALLOC(st->host);
+
+	if (port) {
+		st->port = git__strdup(port);
+		GITERR_CHECK_ALLOC(st->port);
+	}
+
+	st->parent.version = GIT_STREAM_VERSION;
+	st->parent.connect = socket_connect;
+	st->parent.write = socket_write;
+	st->parent.read = socket_read;
+	st->parent.close = socket_close;
+	st->parent.free = socket_free;
+	st->s = INVALID_SOCKET;
+
+	*out = (git_stream *) st;
+	return 0;
+}

src/socket_stream.h

+/*
+ * 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.
+ */
+#ifndef INCLUDE_socket_stream_h__
+#define INCLUDE_socket_stream_h__
+
+#include "netops.h"
+
+typedef struct {
+	git_stream parent;
+	char *host;
+	char *port;
+	GIT_SOCKET s;
+} git_socket_stream;
+
+extern int git_socket_stream_new(git_stream **out, const char *host, const char *port);
+
+#endif

src/stream.h

+/*
+ * 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.
+ */
+#ifndef INCLUDE_stream_h__
+#define INCLUDE_stream_h__
+
+#include "common.h"
+#include "git2/sys/stream.h"
+
+GIT_INLINE(int) git_stream_connect(git_stream *st)
+{
+	return st->connect(st);
+}
+
+GIT_INLINE(int) git_stream_certificate(git_cert **out, git_stream *st)
+{
+	if (!st->encrypted) {
+		giterr_set(GITERR_INVALID, "an unencrypted stream does not have a certificate");
+		return -1;
+	}
+
+	return st->certificate(out, st);
+}
+
+GIT_INLINE(ssize_t) git_stream_read(git_stream *st, void *data, size_t len)
+{
+	return st->read(st, data, len);
+}
+
+GIT_INLINE(ssize_t) git_stream_write(git_stream *st, const char *data, size_t len, int flags)
+{
+	return st->write(st, data, len, flags);
+}
+
+GIT_INLINE(int) git_stream_close(git_stream *st)
+{
+	return st->close(st);
+}
+
+GIT_INLINE(void) git_stream_free(git_stream *st)
+{
+	st->free(st);
+}
+
+#endif

src/transports/git.c

@@ -9,6 +9,8 @@
 #include "buffer.h"
 #include "netops.h"
 #include "git2/sys/transport.h"
+#include "stream.h"
+#include "socket_stream.h"
 
 #define OWNING_SUBTRANSPORT(s) ((git_subtransport *)(s)->parent.subtransport)
 
@@ -18,16 +20,16 @@ static const char cmd_receivepack[] = "git-receive-pack";
 
 typedef struct {
 	git_smart_subtransport_stream parent;
-	gitno_socket socket;
+	git_stream *io;
 	const char *cmd;
 	char *url;
 	unsigned sent_command : 1;
-} git_stream;
+} git_proto_stream;
 
 typedef struct {
 	git_smart_subtransport parent;
 	git_transport *owner;
-	git_stream *current_stream;
+	git_proto_stream *current_stream;
 } git_subtransport;
 
 /*
@@ -67,7 +69,7 @@ static int gen_proto(git_buf *request, const char *cmd, const char *url)
 	return 0;
 }
 
-static int send_command(git_stream *s)
+static int send_command(git_proto_stream *s)
 {
 	int error;
 	git_buf request = GIT_BUF_INIT;
@@ -76,10 +78,7 @@ static int send_command(git_stream *s)
 	if (error < 0)
 		goto cleanup;
 
-	/* It looks like negative values are errors here, and positive values
-	 * are the number of bytes sent. */
-	error = gitno_send(&s->socket, request.ptr, request.size, 0);
-
+	error = git_stream_write(s->io, request.ptr, request.size, 0);
 	if (error >= 0)
 		s->sent_command = 1;
 
@@ -88,14 +87,14 @@ cleanup:
 	return error;
 }
 
-static int git_stream_read(
+static int git_proto_stream_read(
 	git_smart_subtransport_stream *stream,
 	char *buffer,
 	size_t buf_size,
 	size_t *bytes_read)
 {
 	int error;
-	git_stream *s = (git_stream *)stream;
+	git_proto_stream *s = (git_proto_stream *)stream;
 	gitno_buffer buf;
 
 	*bytes_read = 0;
@@ -103,7 +102,7 @@ static int git_stream_read(
 	if (!s->sent_command && (error = send_command(s)) < 0)
 		return error;
 
-	gitno_buffer_setup(&s->socket, &buf, buffer, buf_size);
+	gitno_buffer_setup_fromstream(s->io, &buf, buffer, buf_size);
 
 	if ((error = gitno_recv(&buf)) < 0)
 		return error;
@@ -113,23 +112,23 @@ static int git_stream_read(
 	return 0;
 }
 
-static int git_stream_write(
+static int git_proto_stream_write(
 	git_smart_subtransport_stream *stream,
 	const char *buffer,
 	size_t len)
 {
 	int error;
-	git_stream *s = (git_stream *)stream;
+	git_proto_stream *s = (git_proto_stream *)stream;
 
 	if (!s->sent_command && (error = send_command(s)) < 0)
 		return error;
 
-	return gitno_send(&s->socket, buffer, len, 0);
+	return git_stream_write(s->io, buffer, len, 0);
 }
 
-static void git_stream_free(git_smart_subtransport_stream *stream)
+static void git_proto_stream_free(git_smart_subtransport_stream *stream)
 {
-	git_stream *s = (git_stream *)stream;
+	git_proto_stream *s = (git_proto_stream *)stream;
 	git_subtransport *t = OWNING_SUBTRANSPORT(s);
 	int ret;
 
@@ -137,33 +136,31 @@ static void git_stream_free(git_smart_subtransport_stream *stream)
 
 	t->current_stream = NULL;
 
-	if (s->socket.socket) {
-		ret = gitno_close(&s->socket);
-		assert(!ret);
-	}
-
+	git_stream_free(s->io);
 	git__free(s->url);
 	git__free(s);
 }
 
-static int git_stream_alloc(
+static int git_proto_stream_alloc(
 	git_subtransport *t,
 	const char *url,
 	const char *cmd,
+	const char *host,
+	const char *port,
 	git_smart_subtransport_stream **stream)
 {
-	git_stream *s;
+	git_proto_stream *s;
 
 	if (!stream)
 		return -1;
 
-	s = git__calloc(sizeof(git_stream), 1);
+	s = git__calloc(sizeof(git_proto_stream), 1);
 	GITERR_CHECK_ALLOC(s);
 
 	s->parent.subtransport = &t->parent;
-	s->parent.read = git_stream_read;
-	s->parent.write = git_stream_write;
-	s->parent.free = git_stream_free;
+	s->parent.read = git_proto_stream_read;
+	s->parent.write = git_proto_stream_write;
+	s->parent.free = git_proto_stream_free;
 
 	s->cmd = cmd;
 	s->url = git__strdup(url);
@@ -173,6 +170,11 @@ static int git_stream_alloc(
 		return -1;
 	}
 
+	if ((git_socket_stream_new(&s->io, host, port)) < 0)
+		return -1;
+
+	GITERR_CHECK_VERSION(s->io, GIT_STREAM_VERSION, "git_stream");
+
 	*stream = &s->parent;
 	return 0;
 }
@@ -184,7 +186,7 @@ static int _git_uploadpack_ls(
 {
 	char *host=NULL, *port=NULL, *path=NULL, *user=NULL, *pass=NULL;
 	const char *stream_url = url;
-	git_stream *s;
+	git_proto_stream *s;
 	int error;
 
 	*stream = NULL;
@@ -192,26 +194,32 @@ static int _git_uploadpack_ls(
 	if (!git__prefixcmp(url, prefix_git))
 		stream_url += strlen(prefix_git);
 
-	if ((error = git_stream_alloc(t, stream_url, cmd_uploadpack, stream)) < 0)
+	if ((error = gitno_extract_url_parts(&host, &port, &path, &user, &pass, url, GIT_DEFAULT_PORT)) < 0)
 		return error;
 
-	s = (git_stream *)*stream;
+	error = git_proto_stream_alloc(t, stream_url, cmd_uploadpack, host, port, stream);
 
-	if (!(error = gitno_extract_url_parts(
-			&host, &port, &path, &user, &pass, url, GIT_DEFAULT_PORT))) {
+	git__free(host);
+	git__free(port);
+	git__free(path);
+	git__free(user);
+	git__free(pass);
 
-		if (!(error = gitno_connect(&s->socket, host, port, 0)))
-			t->current_stream = s;
 
-		git__free(host);
-		git__free(port);
-		git__free(path);
-		git__free(user);
-		git__free(pass);
-	} else if (*stream)
-		git_stream_free(*stream);
+	if (error < 0) {
+		git_proto_stream_free(*stream);
+		return error;
+	}
 
-	return error;
+	s = (git_proto_stream *) *stream;
+	if ((error = git_stream_connect(s->io)) < 0) {
+		git_proto_stream_free(*stream);
+		return error;
+	}
+
+	t->current_stream = s;
+
+	return 0;
 }
 
 static int _git_uploadpack(
@@ -237,31 +245,37 @@ static int _git_receivepack_ls(
 {
 	char *host=NULL, *port=NULL, *path=NULL, *user=NULL, *pass=NULL;
 	const char *stream_url = url;
-	git_stream *s;
+	git_proto_stream *s;
 	int error;
 
 	*stream = NULL;
 	if (!git__prefixcmp(url, prefix_git))
 		stream_url += strlen(prefix_git);
 
-	if (git_stream_alloc(t, stream_url, cmd_receivepack, stream) < 0)
-		return -1;
+	if ((error = gitno_extract_url_parts(&host, &port, &path, &user, &pass, url, GIT_DEFAULT_PORT)) < 0)
+		return error;
+
+	error = git_proto_stream_alloc(t, stream_url, cmd_receivepack, host, port, stream);
+
+	git__free(host);
+	git__free(port);
+	git__free(path);
+	git__free(user);
+	git__free(pass);
 
-	s = (git_stream *)*stream;
+	if (error < 0) {
+		git_proto_stream_free(*stream);
+		return error;
+	}
+
+	s = (git_proto_stream *) *stream;
 
-	if (!(error = gitno_extract_url_parts(&host, &port, &path, &user, &pass, url, GIT_DEFAULT_PORT))) {
-		if (!(error = gitno_connect(&s->socket, host, port, 0)))
-			t->current_stream = s;
+	if ((error = git_stream_connect(s->io)) < 0)
+		return error;
 
-		git__free(host);
-		git__free(port);
-		git__free(path);
-		git__free(user);
-		git__free(pass);
-	} else if (*stream)
-		git_stream_free(*stream);
+	t->current_stream = s;
 
-	return error;
+	return 0;
 }
 
 static int _git_receivepack(

src/transports/http.c

@@ -13,16 +13,14 @@
 #include "smart.h"
 #include "auth.h"
 #include "auth_negotiate.h"
+#include "openssl_stream.h"
+#include "socket_stream.h"
 
 git_http_auth_scheme auth_schemes[] = {
 	{ GIT_AUTHTYPE_NEGOTIATE, "Negotiate", GIT_CREDTYPE_DEFAULT, git_http_auth_negotiate },
 	{ GIT_AUTHTYPE_BASIC, "Basic", GIT_CREDTYPE_USERPASS_PLAINTEXT, git_http_auth_basic },
 };
 
-#ifdef GIT_SSL
-# include <openssl/x509v3.h>
-#endif
-
 static const char *upload_pack_service = "upload-pack";
 static const char *upload_pack_ls_service_url = "/info/refs?service=git-upload-pack";
 static const char *upload_pack_service_url = "/git-upload-pack";
@@ -62,7 +60,7 @@ typedef struct {
 typedef struct {
 	git_smart_subtransport parent;
 	transport_smart *owner;
-	gitno_socket socket;
+	git_stream *io;
 	gitno_connection_data connection_data;
 	bool connected;
 
@@ -474,7 +472,7 @@ static int on_body_fill_buffer(http_parser *parser, const char *str, size_t len)
 static void clear_parser_state(http_subtransport *t)
 {
 	http_parser_init(&t->parser, HTTP_RESPONSE);
-	gitno_buffer_setup(&t->socket,
+	gitno_buffer_setup_fromstream(t->io,
 		&t->parse_buffer,
 		t->parse_buffer_data,
 		sizeof(t->parse_buffer_data));
@@ -498,7 +496,7 @@ static void clear_parser_state(http_subtransport *t)
 	git_vector_free_deep(&t->www_authenticate);
 }
 
-static int write_chunk(gitno_socket *socket, const char *buffer, size_t len)
+static int write_chunk(git_stream *io, const char *buffer, size_t len)
 {
 	git_buf buf = GIT_BUF_INIT;
 
@@ -508,7 +506,7 @@ static int write_chunk(gitno_socket *socket, const char *buffer, size_t len)
 	if (git_buf_oom(&buf))
 		return -1;
 
-	if (gitno_send(socket, buf.ptr, buf.size, 0) < 0) {
+	if (git_stream_write(io, buf.ptr, buf.size, 0) < 0) {
 		git_buf_free(&buf);
 		return -1;
 	}
@@ -516,11 +514,11 @@ static int write_chunk(gitno_socket *socket, const char *buffer, size_t len)
 	git_buf_free(&buf);
 
 	/* Chunk body */
-	if (len > 0 && gitno_send(socket, buffer, len, 0) < 0)
+	if (len > 0 && git_stream_write(io, buffer, len, 0) < 0)
 		return -1;
 
 	/* Chunk footer */
-	if (gitno_send(socket, "\r\n", 2, 0) < 0)
+	if (git_stream_write(io, "\r\n", 2, 0) < 0)
 		return -1;
 
 	return 0;
@@ -528,64 +526,43 @@ static int write_chunk(gitno_socket *socket, const char *buffer, size_t len)
 
 static int http_connect(http_subtransport *t)
 {
-	int flags = 0, error;
+	int error;
 
 	if (t->connected &&
 		http_should_keep_alive(&t->parser) &&
 		t->parse_finished)
 		return 0;
 
-	if (t->socket.socket)
-		gitno_close(&t->socket);
+	if (t->io) {
+		git_stream_close(t->io);
+		git_stream_free(t->io);
+		t->io = NULL;
+	}
 
 	if (t->connection_data.use_ssl) {
-		int tflags;
+		error = git_openssl_stream_new(&t->io, t->connection_data.host, t->connection_data.port);
+	} else {
+		error = git_socket_stream_new(&t->io,  t->connection_data.host, t->connection_data.port);
+	}
 
-		if (t->owner->parent.read_flags(&t->owner->parent, &tflags) < 0)
-			return -1;
+	if (error < 0)
+		return error;
 
-		flags |= GITNO_CONNECT_SSL;
-	}
+	GITERR_CHECK_VERSION(t->io, GIT_STREAM_VERSION, "git_stream");
 
-	error = gitno_connect(&t->socket, t->connection_data.host, t->connection_data.port, flags);
+	error = git_stream_connect(t->io);
 
 #ifdef GIT_SSL
 	if ((!error || error == GIT_ECERTIFICATE) && t->owner->certificate_check_cb != NULL) {
-                X509 *cert = SSL_get_peer_certificate(t->socket.ssl.ssl);
-		git_cert_x509 cert_info, *cert_info_ptr;
-                int len, is_valid;
-		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;
-		}
-
+		git_cert *cert;
+		int is_valid;
 
-		encoded_cert = git__malloc(len);
-		GITERR_CHECK_ALLOC(encoded_cert);
-		/* i2d_X509 makes 'copy' 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;
-		}
+		if ((error = git_stream_certificate(&cert, t->io)) < 0)
+			return error;
 
 		giterr_clear();
 		is_valid = error != GIT_ECERTIFICATE;
-		cert_info.cert_type = GIT_CERT_X509;
-		cert_info.data = encoded_cert;
-		cert_info.len = len;
-
-		cert_info_ptr = &cert_info;
-
-		error = t->owner->certificate_check_cb((git_cert *) cert_info_ptr, is_valid, t->connection_data.host, t->owner->message_cb_payload);
-		git__free(encoded_cert);
+		error = t->owner->certificate_check_cb(cert, is_valid, t->connection_data.host, t->owner->message_cb_payload);
 
 		if (error < 0) {
 			if (!giterr_last())
@@ -626,7 +603,7 @@ replay:
 		if (gen_request(&request, s, 0) < 0)
 			return -1;
 
-		if (gitno_send(&t->socket, request.ptr, request.size, 0) < 0) {
+		if (git_stream_write(t->io, request.ptr, request.size, 0) < 0) {
 			git_buf_free(&request);
 			return -1;
 		}
@@ -642,13 +619,13 @@ replay:
 
 			/* Flush, if necessary */
 			if (s->chunk_buffer_len > 0 &&
-				write_chunk(&t->socket, s->chunk_buffer, s->chunk_buffer_len) < 0)
+				write_chunk(t->io, s->chunk_buffer, s->chunk_buffer_len) < 0)
 				return -1;
 
 			s->chunk_buffer_len = 0;
 
 			/* Write the final chunk. */
-			if (gitno_send(&t->socket, "0\r\n\r\n", 5, 0) < 0)
+			if (git_stream_write(t->io, "0\r\n\r\n", 5, 0) < 0)
 				return -1;
 		}
 
@@ -743,7 +720,7 @@ static int http_stream_write_chunked(
 		if (gen_request(&request, s, 0) < 0)
 			return -1;
 
-		if (gitno_send(&t->socket, request.ptr, request.size, 0) < 0) {
+		if (git_stream_write(t->io, request.ptr, request.size, 0) < 0) {
 			git_buf_free(&request);
 			return -1;
 		}
@@ -756,14 +733,14 @@ static int http_stream_write_chunked(
 	if (len > CHUNK_SIZE) {
 		/* Flush, if necessary */
 		if (s->chunk_buffer_len > 0) {
-			if (write_chunk(&t->socket, s->chunk_buffer, s->chunk_buffer_len) < 0)
+			if (write_chunk(t->io, s->chunk_buffer, s->chunk_buffer_len) < 0)
 				return -1;
 
 			s->chunk_buffer_len = 0;
 		}
 
 		/* Write chunk directly */
-		if (write_chunk(&t->socket, buffer, len) < 0)
+		if (write_chunk(t->io, buffer, len) < 0)
 			return -1;
 	}
 	else {
@@ -780,7 +757,7 @@ static int http_stream_write_chunked(
 
 		/* Is the buffer full? If so, then flush */
 		if (CHUNK_SIZE == s->chunk_buffer_len) {
-			if (write_chunk(&t->socket, s->chunk_buffer, s->chunk_buffer_len) < 0)
+			if (write_chunk(t->io, s->chunk_buffer, s->chunk_buffer_len) < 0)
 				return -1;
 
 			s->chunk_buffer_len = 0;
@@ -816,10 +793,10 @@ static int http_stream_write_single(
 	if (gen_request(&request, s, len) < 0)
 		return -1;
 
-	if (gitno_send(&t->socket, request.ptr, request.size, 0) < 0)
+	if (git_stream_write(t->io, request.ptr, request.size, 0) < 0)
 		goto on_error;
 
-	if (len && gitno_send(&t->socket, buffer, len, 0) < 0)
+	if (len && git_stream_write(t->io, buffer, len, 0) < 0)
 		goto on_error;
 
 	git_buf_free(&request);
@@ -986,9 +963,10 @@ static int http_close(git_smart_subtransport *subtransport)
 
 	clear_parser_state(t);
 
-	if (t->socket.socket) {
-		gitno_close(&t->socket);
-		memset(&t->socket, 0x0, sizeof(gitno_socket));
+	if (t->io) {
+		git_stream_close(t->io);
+		git_stream_free(t->io);
+		t->io = NULL;
 	}
 
 	if (t->cred) {

src/transports/smart.c

@@ -158,7 +158,7 @@ static int git_smart__connect(
 	/* Save off the current stream (i.e. socket) that we are working with */
 	t->current_stream = stream;
 
-	gitno_buffer_setup_callback(NULL, &t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
+	gitno_buffer_setup_callback(&t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
 
 	/* 2 flushes for RPC; 1 for stateful */
 	if ((error = git_smart__store_refs(t, t->rpc ? 2 : 1)) < 0)
@@ -252,7 +252,7 @@ int git_smart__negotiation_step(git_transport *transport, void *data, size_t len
 	if ((error = stream->write(stream, (const char *)data, len)) < 0)
 		return error;
 
-	gitno_buffer_setup_callback(NULL, &t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
+	gitno_buffer_setup_callback(&t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
 
 	return 0;
 }
@@ -278,7 +278,7 @@ int git_smart__get_push_stream(transport_smart *t, git_smart_subtransport_stream
 	/* Save off the current stream (i.e. socket) that we are working with */
 	t->current_stream = *stream;
 
-	gitno_buffer_setup_callback(NULL, &t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
+	gitno_buffer_setup_callback(&t->buffer, t->buffer_data, sizeof(t->buffer_data), git_smart__recv_cb, t);
 
 	return 0;
 }

src/transports/ssh.c

@@ -14,6 +14,7 @@
 #include "netops.h"
 #include "smart.h"
 #include "cred.h"
+#include "socket_stream.h"
 
 #ifdef GIT_SSH
 
@@ -25,7 +26,7 @@ static const char cmd_receivepack[] = "git-receive-pack";
 
 typedef struct {
 	git_smart_subtransport_stream parent;
-	gitno_socket socket;
+	git_stream *io;
 	LIBSSH2_SESSION *session;
 	LIBSSH2_CHANNEL *channel;
 	const char *cmd;
@@ -183,9 +184,10 @@ static void ssh_stream_free(git_smart_subtransport_stream *stream)
 		s->session = NULL;
 	}
 
-	if (s->socket.socket) {
-		(void)gitno_close(&s->socket);
-		/* can't do anything here with error return value */
+	if (s->io) {
+		git_stream_close(s->io);
+		git_stream_free(s->io);
+		s->io = NULL;
 	}
 
 	git__free(s->url);
@@ -413,10 +415,11 @@ static int request_creds(git_cred **out, ssh_subtransport *t, const char *user,
 
 static int _git_ssh_session_create(
 	LIBSSH2_SESSION** session,
-	gitno_socket socket)
+	git_stream *io)
 {
 	int rc = 0;
 	LIBSSH2_SESSION* s;
+	git_socket_stream *socket = (git_socket_stream *) io;
 
 	assert(session);
 
@@ -427,7 +430,7 @@ static int _git_ssh_session_create(
 	}
 
 	do {
-		rc = libssh2_session_startup(s, socket.socket);
+		rc = libssh2_session_startup(s, socket->s);
 	} while (LIBSSH2_ERROR_EAGAIN == rc || LIBSSH2_ERROR_TIMEOUT == rc);
 
 	if (rc != LIBSSH2_ERROR_NONE) {
@@ -477,10 +480,11 @@ static int _git_ssh_setup_conn(
 		GITERR_CHECK_ALLOC(port);
 	}
 
-	if ((error = gitno_connect(&s->socket, host, port, 0)) < 0)
+	if ((error = git_socket_stream_new(&s->io, host, port)) < 0 ||
+	    (error = git_stream_connect(s->io)) < 0)
 		goto done;
 
-	if ((error = _git_ssh_session_create(&session, s->socket)) < 0)
+	if ((error = _git_ssh_session_create(&session, s->io)) < 0)
 		goto done;
 
 	if (t->owner->certificate_check_cb != NULL) {