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-rw-r--r--src/libgit2/transports/ssh.c915
1 files changed, 915 insertions, 0 deletions
diff --git a/src/libgit2/transports/ssh.c b/src/libgit2/transports/ssh.c
new file mode 100644
index 000000000..89f085230
--- /dev/null
+++ b/src/libgit2/transports/ssh.c
@@ -0,0 +1,915 @@
+/*
+ * 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 "ssh.h"
+
+#ifdef GIT_SSH
+#include <libssh2.h>
+#endif
+
+#include "runtime.h"
+#include "net.h"
+#include "netops.h"
+#include "smart.h"
+#include "streams/socket.h"
+
+#include "git2/credential.h"
+#include "git2/sys/credential.h"
+
+#ifdef GIT_SSH
+
+#define OWNING_SUBTRANSPORT(s) ((ssh_subtransport *)(s)->parent.subtransport)
+
+static const char cmd_uploadpack[] = "git-upload-pack";
+static const char cmd_receivepack[] = "git-receive-pack";
+
+typedef struct {
+ git_smart_subtransport_stream parent;
+ git_stream *io;
+ LIBSSH2_SESSION *session;
+ LIBSSH2_CHANNEL *channel;
+ const char *cmd;
+ git_net_url url;
+ unsigned sent_command : 1;
+} ssh_stream;
+
+typedef struct {
+ git_smart_subtransport parent;
+ transport_smart *owner;
+ ssh_stream *current_stream;
+ git_credential *cred;
+ char *cmd_uploadpack;
+ char *cmd_receivepack;
+} ssh_subtransport;
+
+static int list_auth_methods(int *out, LIBSSH2_SESSION *session, const char *username);
+
+static void ssh_error(LIBSSH2_SESSION *session, const char *errmsg)
+{
+ char *ssherr;
+ libssh2_session_last_error(session, &ssherr, NULL, 0);
+
+ git_error_set(GIT_ERROR_SSH, "%s: %s", errmsg, ssherr);
+}
+
+/*
+ * Create a git protocol request.
+ *
+ * For example: git-upload-pack '/libgit2/libgit2'
+ */
+static int gen_proto(git_str *request, const char *cmd, git_net_url *url)
+{
+ const char *repo;
+
+ repo = url->path;
+
+ if (repo && repo[0] == '/' && repo[1] == '~')
+ repo++;
+
+ if (!repo || !repo[0]) {
+ git_error_set(GIT_ERROR_NET, "malformed git protocol URL");
+ return -1;
+ }
+
+ git_str_puts(request, cmd);
+ git_str_puts(request, " '");
+ git_str_puts(request, repo);
+ git_str_puts(request, "'");
+
+ if (git_str_oom(request))
+ return -1;
+
+ return 0;
+}
+
+static int send_command(ssh_stream *s)
+{
+ int error;
+ git_str request = GIT_STR_INIT;
+
+ error = gen_proto(&request, s->cmd, &s->url);
+ if (error < 0)
+ goto cleanup;
+
+ error = libssh2_channel_exec(s->channel, request.ptr);
+ if (error < LIBSSH2_ERROR_NONE) {
+ ssh_error(s->session, "SSH could not execute request");
+ goto cleanup;
+ }
+
+ s->sent_command = 1;
+
+cleanup:
+ git_str_dispose(&request);
+ return error;
+}
+
+static int ssh_stream_read(
+ git_smart_subtransport_stream *stream,
+ char *buffer,
+ size_t buf_size,
+ size_t *bytes_read)
+{
+ int rc;
+ ssh_stream *s = GIT_CONTAINER_OF(stream, ssh_stream, parent);
+
+ *bytes_read = 0;
+
+ if (!s->sent_command && send_command(s) < 0)
+ return -1;
+
+ if ((rc = libssh2_channel_read(s->channel, buffer, buf_size)) < LIBSSH2_ERROR_NONE) {
+ ssh_error(s->session, "SSH could not read data");
+ return -1;
+ }
+
+ /*
+ * If we can't get anything out of stdout, it's typically a
+ * not-found error, so read from stderr and signal EOF on
+ * stderr.
+ */
+ if (rc == 0) {
+ if ((rc = libssh2_channel_read_stderr(s->channel, buffer, buf_size)) > 0) {
+ git_error_set(GIT_ERROR_SSH, "%*s", rc, buffer);
+ return GIT_EEOF;
+ } else if (rc < LIBSSH2_ERROR_NONE) {
+ ssh_error(s->session, "SSH could not read stderr");
+ return -1;
+ }
+ }
+
+
+ *bytes_read = rc;
+
+ return 0;
+}
+
+static int ssh_stream_write(
+ git_smart_subtransport_stream *stream,
+ const char *buffer,
+ size_t len)
+{
+ ssh_stream *s = GIT_CONTAINER_OF(stream, ssh_stream, parent);
+ size_t off = 0;
+ ssize_t ret = 0;
+
+ if (!s->sent_command && send_command(s) < 0)
+ return -1;
+
+ do {
+ ret = libssh2_channel_write(s->channel, buffer + off, len - off);
+ if (ret < 0)
+ break;
+
+ off += ret;
+
+ } while (off < len);
+
+ if (ret < 0) {
+ ssh_error(s->session, "SSH could not write data");
+ return -1;
+ }
+
+ return 0;
+}
+
+static void ssh_stream_free(git_smart_subtransport_stream *stream)
+{
+ ssh_stream *s = GIT_CONTAINER_OF(stream, ssh_stream, parent);
+ ssh_subtransport *t;
+
+ if (!stream)
+ return;
+
+ t = OWNING_SUBTRANSPORT(s);
+ t->current_stream = NULL;
+
+ if (s->channel) {
+ libssh2_channel_close(s->channel);
+ libssh2_channel_free(s->channel);
+ s->channel = NULL;
+ }
+
+ if (s->session) {
+ libssh2_session_disconnect(s->session, "closing transport");
+ libssh2_session_free(s->session);
+ s->session = NULL;
+ }
+
+ if (s->io) {
+ git_stream_close(s->io);
+ git_stream_free(s->io);
+ s->io = NULL;
+ }
+
+ git_net_url_dispose(&s->url);
+ git__free(s);
+}
+
+static int ssh_stream_alloc(
+ ssh_subtransport *t,
+ const char *cmd,
+ git_smart_subtransport_stream **stream)
+{
+ ssh_stream *s;
+
+ GIT_ASSERT_ARG(stream);
+
+ s = git__calloc(sizeof(ssh_stream), 1);
+ GIT_ERROR_CHECK_ALLOC(s);
+
+ s->parent.subtransport = &t->parent;
+ s->parent.read = ssh_stream_read;
+ s->parent.write = ssh_stream_write;
+ s->parent.free = ssh_stream_free;
+
+ s->cmd = cmd;
+
+ *stream = &s->parent;
+ return 0;
+}
+
+static int ssh_agent_auth(LIBSSH2_SESSION *session, git_credential_ssh_key *c) {
+ int rc = LIBSSH2_ERROR_NONE;
+
+ struct libssh2_agent_publickey *curr, *prev = NULL;
+
+ LIBSSH2_AGENT *agent = libssh2_agent_init(session);
+
+ if (agent == NULL)
+ return -1;
+
+ rc = libssh2_agent_connect(agent);
+
+ if (rc != LIBSSH2_ERROR_NONE)
+ goto shutdown;
+
+ rc = libssh2_agent_list_identities(agent);
+
+ if (rc != LIBSSH2_ERROR_NONE)
+ goto shutdown;
+
+ while (1) {
+ rc = libssh2_agent_get_identity(agent, &curr, prev);
+
+ if (rc < 0)
+ goto shutdown;
+
+ /* rc is set to 1 whenever the ssh agent ran out of keys to check.
+ * Set the error code to authentication failure rather than erroring
+ * out with an untranslatable error code.
+ */
+ if (rc == 1) {
+ rc = LIBSSH2_ERROR_AUTHENTICATION_FAILED;
+ goto shutdown;
+ }
+
+ rc = libssh2_agent_userauth(agent, c->username, curr);
+
+ if (rc == 0)
+ break;
+
+ prev = curr;
+ }
+
+shutdown:
+
+ if (rc != LIBSSH2_ERROR_NONE)
+ ssh_error(session, "error authenticating");
+
+ libssh2_agent_disconnect(agent);
+ libssh2_agent_free(agent);
+
+ return rc;
+}
+
+static int _git_ssh_authenticate_session(
+ LIBSSH2_SESSION *session,
+ git_credential *cred)
+{
+ int rc;
+
+ do {
+ git_error_clear();
+ switch (cred->credtype) {
+ case GIT_CREDENTIAL_USERPASS_PLAINTEXT: {
+ git_credential_userpass_plaintext *c = (git_credential_userpass_plaintext *)cred;
+ rc = libssh2_userauth_password(session, c->username, c->password);
+ break;
+ }
+ case GIT_CREDENTIAL_SSH_KEY: {
+ git_credential_ssh_key *c = (git_credential_ssh_key *)cred;
+
+ if (c->privatekey)
+ rc = libssh2_userauth_publickey_fromfile(
+ session, c->username, c->publickey,
+ c->privatekey, c->passphrase);
+ else
+ rc = ssh_agent_auth(session, c);
+
+ break;
+ }
+ case GIT_CREDENTIAL_SSH_CUSTOM: {
+ git_credential_ssh_custom *c = (git_credential_ssh_custom *)cred;
+
+ rc = libssh2_userauth_publickey(
+ session, c->username, (const unsigned char *)c->publickey,
+ c->publickey_len, c->sign_callback, &c->payload);
+ break;
+ }
+ case GIT_CREDENTIAL_SSH_INTERACTIVE: {
+ void **abstract = libssh2_session_abstract(session);
+ git_credential_ssh_interactive *c = (git_credential_ssh_interactive *)cred;
+
+ /* ideally, we should be able to set this by calling
+ * libssh2_session_init_ex() instead of libssh2_session_init().
+ * libssh2's API is inconsistent here i.e. libssh2_userauth_publickey()
+ * allows you to pass the `abstract` as part of the call, whereas
+ * libssh2_userauth_keyboard_interactive() does not!
+ *
+ * The only way to set the `abstract` pointer is by calling
+ * libssh2_session_abstract(), which will replace the existing
+ * pointer as is done below. This is safe for now (at time of writing),
+ * but may not be valid in future.
+ */
+ *abstract = c->payload;
+
+ rc = libssh2_userauth_keyboard_interactive(
+ session, c->username, c->prompt_callback);
+ break;
+ }
+#ifdef GIT_SSH_MEMORY_CREDENTIALS
+ case GIT_CREDENTIAL_SSH_MEMORY: {
+ git_credential_ssh_key *c = (git_credential_ssh_key *)cred;
+
+ GIT_ASSERT(c->username);
+ GIT_ASSERT(c->privatekey);
+
+ rc = libssh2_userauth_publickey_frommemory(
+ session,
+ c->username,
+ strlen(c->username),
+ c->publickey,
+ c->publickey ? strlen(c->publickey) : 0,
+ c->privatekey,
+ strlen(c->privatekey),
+ c->passphrase);
+ break;
+ }
+#endif
+ default:
+ rc = LIBSSH2_ERROR_AUTHENTICATION_FAILED;
+ }
+ } while (LIBSSH2_ERROR_EAGAIN == rc || LIBSSH2_ERROR_TIMEOUT == rc);
+
+ if (rc == LIBSSH2_ERROR_PASSWORD_EXPIRED ||
+ rc == LIBSSH2_ERROR_AUTHENTICATION_FAILED ||
+ rc == LIBSSH2_ERROR_PUBLICKEY_UNVERIFIED)
+ return GIT_EAUTH;
+
+ if (rc != LIBSSH2_ERROR_NONE) {
+ if (!git_error_last())
+ ssh_error(session, "Failed to authenticate SSH session");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int request_creds(git_credential **out, ssh_subtransport *t, const char *user, int auth_methods)
+{
+ int error, no_callback = 0;
+ git_credential *cred = NULL;
+
+ if (!t->owner->connect_opts.callbacks.credentials) {
+ no_callback = 1;
+ } else {
+ error = t->owner->connect_opts.callbacks.credentials(
+ &cred,
+ t->owner->url,
+ user,
+ auth_methods,
+ t->owner->connect_opts.callbacks.payload);
+
+ if (error == GIT_PASSTHROUGH) {
+ no_callback = 1;
+ } else if (error < 0) {
+ return error;
+ } else if (!cred) {
+ git_error_set(GIT_ERROR_SSH, "callback failed to initialize SSH credentials");
+ return -1;
+ }
+ }
+
+ if (no_callback) {
+ git_error_set(GIT_ERROR_SSH, "authentication required but no callback set");
+ return GIT_EAUTH;
+ }
+
+ if (!(cred->credtype & auth_methods)) {
+ cred->free(cred);
+ git_error_set(GIT_ERROR_SSH, "authentication callback returned unsupported credentials type");
+ return GIT_EAUTH;
+ }
+
+ *out = cred;
+
+ return 0;
+}
+
+static int _git_ssh_session_create(
+ LIBSSH2_SESSION **session,
+ git_stream *io)
+{
+ int rc = 0;
+ LIBSSH2_SESSION *s;
+ git_socket_stream *socket = GIT_CONTAINER_OF(io, git_socket_stream, parent);
+
+ GIT_ASSERT_ARG(session);
+
+ s = libssh2_session_init();
+ if (!s) {
+ git_error_set(GIT_ERROR_NET, "failed to initialize SSH session");
+ return -1;
+ }
+
+ do {
+ rc = libssh2_session_handshake(s, socket->s);
+ } while (LIBSSH2_ERROR_EAGAIN == rc || LIBSSH2_ERROR_TIMEOUT == rc);
+
+ if (rc != LIBSSH2_ERROR_NONE) {
+ ssh_error(s, "failed to start SSH session");
+ libssh2_session_free(s);
+ return -1;
+ }
+
+ libssh2_session_set_blocking(s, 1);
+
+ *session = s;
+
+ return 0;
+}
+
+#define SSH_DEFAULT_PORT "22"
+
+static int _git_ssh_setup_conn(
+ ssh_subtransport *t,
+ const char *url,
+ const char *cmd,
+ git_smart_subtransport_stream **stream)
+{
+ int auth_methods, error = 0;
+ ssh_stream *s;
+ git_credential *cred = NULL;
+ LIBSSH2_SESSION *session=NULL;
+ LIBSSH2_CHANNEL *channel=NULL;
+
+ t->current_stream = NULL;
+
+ *stream = NULL;
+ if (ssh_stream_alloc(t, cmd, stream) < 0)
+ return -1;
+
+ s = (ssh_stream *)*stream;
+ s->session = NULL;
+ s->channel = NULL;
+
+ if (git_net_str_is_url(url))
+ error = git_net_url_parse(&s->url, url);
+ else
+ error = git_net_url_parse_scp(&s->url, url);
+
+ if (error < 0)
+ goto done;
+
+ if ((error = git_socket_stream_new(&s->io, s->url.host, s->url.port)) < 0 ||
+ (error = git_stream_connect(s->io)) < 0)
+ goto done;
+
+ if ((error = _git_ssh_session_create(&session, s->io)) < 0)
+ goto done;
+
+ if (t->owner->connect_opts.callbacks.certificate_check != NULL) {
+ git_cert_hostkey cert = {{ 0 }}, *cert_ptr;
+ const char *key;
+ size_t cert_len;
+ int cert_type;
+
+ cert.parent.cert_type = GIT_CERT_HOSTKEY_LIBSSH2;
+
+ key = libssh2_session_hostkey(session, &cert_len, &cert_type);
+ if (key != NULL) {
+ cert.type |= GIT_CERT_SSH_RAW;
+ cert.hostkey = key;
+ cert.hostkey_len = cert_len;
+ switch (cert_type) {
+ case LIBSSH2_HOSTKEY_TYPE_RSA:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_RSA;
+ break;
+ case LIBSSH2_HOSTKEY_TYPE_DSS:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_DSS;
+ break;
+
+#ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_256
+ case LIBSSH2_HOSTKEY_TYPE_ECDSA_256:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_KEY_ECDSA_256;
+ break;
+ case LIBSSH2_HOSTKEY_TYPE_ECDSA_384:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_KEY_ECDSA_384;
+ break;
+ case LIBSSH2_KNOWNHOST_KEY_ECDSA_521:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_KEY_ECDSA_521;
+ break;
+#endif
+
+#ifdef LIBSSH2_HOSTKEY_TYPE_ED25519
+ case LIBSSH2_HOSTKEY_TYPE_ED25519:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_KEY_ED25519;
+ break;
+#endif
+ default:
+ cert.raw_type = GIT_CERT_SSH_RAW_TYPE_UNKNOWN;
+ }
+ }
+
+#ifdef LIBSSH2_HOSTKEY_HASH_SHA256
+ key = libssh2_hostkey_hash(session, LIBSSH2_HOSTKEY_HASH_SHA256);
+ if (key != NULL) {
+ cert.type |= GIT_CERT_SSH_SHA256;
+ memcpy(&cert.hash_sha256, key, 32);
+ }
+#endif
+
+ key = libssh2_hostkey_hash(session, LIBSSH2_HOSTKEY_HASH_SHA1);
+ if (key != NULL) {
+ cert.type |= GIT_CERT_SSH_SHA1;
+ memcpy(&cert.hash_sha1, key, 20);
+ }
+
+ key = libssh2_hostkey_hash(session, LIBSSH2_HOSTKEY_HASH_MD5);
+ if (key != NULL) {
+ cert.type |= GIT_CERT_SSH_MD5;
+ memcpy(&cert.hash_md5, key, 16);
+ }
+
+ if (cert.type == 0) {
+ git_error_set(GIT_ERROR_SSH, "unable to get the host key");
+ error = -1;
+ goto done;
+ }
+
+ /* We don't currently trust any hostkeys */
+ git_error_clear();
+
+ cert_ptr = &cert;
+
+ error = t->owner->connect_opts.callbacks.certificate_check(
+ (git_cert *)cert_ptr,
+ 0,
+ s->url.host,
+ t->owner->connect_opts.callbacks.payload);
+
+ if (error < 0 && error != GIT_PASSTHROUGH) {
+ if (!git_error_last())
+ git_error_set(GIT_ERROR_NET, "user cancelled hostkey check");
+
+ goto done;
+ }
+ }
+
+ /* we need the username to ask for auth methods */
+ if (!s->url.username) {
+ if ((error = request_creds(&cred, t, NULL, GIT_CREDENTIAL_USERNAME)) < 0)
+ goto done;
+
+ s->url.username = git__strdup(((git_credential_username *) cred)->username);
+ cred->free(cred);
+ cred = NULL;
+ if (!s->url.username)
+ goto done;
+ } else if (s->url.username && s->url.password) {
+ if ((error = git_credential_userpass_plaintext_new(&cred, s->url.username, s->url.password)) < 0)
+ goto done;
+ }
+
+ if ((error = list_auth_methods(&auth_methods, session, s->url.username)) < 0)
+ goto done;
+
+ error = GIT_EAUTH;
+ /* if we already have something to try */
+ if (cred && auth_methods & cred->credtype)
+ error = _git_ssh_authenticate_session(session, cred);
+
+ while (error == GIT_EAUTH) {
+ if (cred) {
+ cred->free(cred);
+ cred = NULL;
+ }
+
+ if ((error = request_creds(&cred, t, s->url.username, auth_methods)) < 0)
+ goto done;
+
+ if (strcmp(s->url.username, git_credential_get_username(cred))) {
+ git_error_set(GIT_ERROR_SSH, "username does not match previous request");
+ error = -1;
+ goto done;
+ }
+
+ error = _git_ssh_authenticate_session(session, cred);
+
+ if (error == GIT_EAUTH) {
+ /* refresh auth methods */
+ if ((error = list_auth_methods(&auth_methods, session, s->url.username)) < 0)
+ goto done;
+ else
+ error = GIT_EAUTH;
+ }
+ }
+
+ if (error < 0)
+ goto done;
+
+ channel = libssh2_channel_open_session(session);
+ if (!channel) {
+ error = -1;
+ ssh_error(session, "Failed to open SSH channel");
+ goto done;
+ }
+
+ libssh2_channel_set_blocking(channel, 1);
+
+ s->session = session;
+ s->channel = channel;
+
+ t->current_stream = s;
+
+done:
+ if (error < 0) {
+ ssh_stream_free(*stream);
+
+ if (session)
+ libssh2_session_free(session);
+ }
+
+ if (cred)
+ cred->free(cred);
+
+ return error;
+}
+
+static int ssh_uploadpack_ls(
+ ssh_subtransport *t,
+ const char *url,
+ git_smart_subtransport_stream **stream)
+{
+ const char *cmd = t->cmd_uploadpack ? t->cmd_uploadpack : cmd_uploadpack;
+
+ return _git_ssh_setup_conn(t, url, cmd, stream);
+}
+
+static int ssh_uploadpack(
+ ssh_subtransport *t,
+ const char *url,
+ git_smart_subtransport_stream **stream)
+{
+ GIT_UNUSED(url);
+
+ if (t->current_stream) {
+ *stream = &t->current_stream->parent;
+ return 0;
+ }
+
+ git_error_set(GIT_ERROR_NET, "must call UPLOADPACK_LS before UPLOADPACK");
+ return -1;
+}
+
+static int ssh_receivepack_ls(
+ ssh_subtransport *t,
+ const char *url,
+ git_smart_subtransport_stream **stream)
+{
+ const char *cmd = t->cmd_receivepack ? t->cmd_receivepack : cmd_receivepack;
+
+
+ return _git_ssh_setup_conn(t, url, cmd, stream);
+}
+
+static int ssh_receivepack(
+ ssh_subtransport *t,
+ const char *url,
+ git_smart_subtransport_stream **stream)
+{
+ GIT_UNUSED(url);
+
+ if (t->current_stream) {
+ *stream = &t->current_stream->parent;
+ return 0;
+ }
+
+ git_error_set(GIT_ERROR_NET, "must call RECEIVEPACK_LS before RECEIVEPACK");
+ return -1;
+}
+
+static int _ssh_action(
+ git_smart_subtransport_stream **stream,
+ git_smart_subtransport *subtransport,
+ const char *url,
+ git_smart_service_t action)
+{
+ ssh_subtransport *t = GIT_CONTAINER_OF(subtransport, ssh_subtransport, parent);
+
+ switch (action) {
+ case GIT_SERVICE_UPLOADPACK_LS:
+ return ssh_uploadpack_ls(t, url, stream);
+
+ case GIT_SERVICE_UPLOADPACK:
+ return ssh_uploadpack(t, url, stream);
+
+ case GIT_SERVICE_RECEIVEPACK_LS:
+ return ssh_receivepack_ls(t, url, stream);
+
+ case GIT_SERVICE_RECEIVEPACK:
+ return ssh_receivepack(t, url, stream);
+ }
+
+ *stream = NULL;
+ return -1;
+}
+
+static int _ssh_close(git_smart_subtransport *subtransport)
+{
+ ssh_subtransport *t = GIT_CONTAINER_OF(subtransport, ssh_subtransport, parent);
+
+ GIT_ASSERT(!t->current_stream);
+
+ GIT_UNUSED(t);
+
+ return 0;
+}
+
+static void _ssh_free(git_smart_subtransport *subtransport)
+{
+ ssh_subtransport *t = GIT_CONTAINER_OF(subtransport, ssh_subtransport, parent);
+
+ git__free(t->cmd_uploadpack);
+ git__free(t->cmd_receivepack);
+ git__free(t);
+}
+
+#define SSH_AUTH_PUBLICKEY "publickey"
+#define SSH_AUTH_PASSWORD "password"
+#define SSH_AUTH_KEYBOARD_INTERACTIVE "keyboard-interactive"
+
+static int list_auth_methods(int *out, LIBSSH2_SESSION *session, const char *username)
+{
+ const char *list, *ptr;
+
+ *out = 0;
+
+ list = libssh2_userauth_list(session, username, strlen(username));
+
+ /* either error, or the remote accepts NONE auth, which is bizarre, let's punt */
+ if (list == NULL && !libssh2_userauth_authenticated(session)) {
+ ssh_error(session, "Failed to retrieve list of SSH authentication methods");
+ return GIT_EAUTH;
+ }
+
+ ptr = list;
+ while (ptr) {
+ if (*ptr == ',')
+ ptr++;
+
+ if (!git__prefixcmp(ptr, SSH_AUTH_PUBLICKEY)) {
+ *out |= GIT_CREDENTIAL_SSH_KEY;
+ *out |= GIT_CREDENTIAL_SSH_CUSTOM;
+#ifdef GIT_SSH_MEMORY_CREDENTIALS
+ *out |= GIT_CREDENTIAL_SSH_MEMORY;
+#endif
+ ptr += strlen(SSH_AUTH_PUBLICKEY);
+ continue;
+ }
+
+ if (!git__prefixcmp(ptr, SSH_AUTH_PASSWORD)) {
+ *out |= GIT_CREDENTIAL_USERPASS_PLAINTEXT;
+ ptr += strlen(SSH_AUTH_PASSWORD);
+ continue;
+ }
+
+ if (!git__prefixcmp(ptr, SSH_AUTH_KEYBOARD_INTERACTIVE)) {
+ *out |= GIT_CREDENTIAL_SSH_INTERACTIVE;
+ ptr += strlen(SSH_AUTH_KEYBOARD_INTERACTIVE);
+ continue;
+ }
+
+ /* Skip it if we don't know it */
+ ptr = strchr(ptr, ',');
+ }
+
+ return 0;
+}
+#endif
+
+int git_smart_subtransport_ssh(
+ git_smart_subtransport **out, git_transport *owner, void *param)
+{
+#ifdef GIT_SSH
+ ssh_subtransport *t;
+
+ GIT_ASSERT_ARG(out);
+
+ GIT_UNUSED(param);
+
+ t = git__calloc(sizeof(ssh_subtransport), 1);
+ GIT_ERROR_CHECK_ALLOC(t);
+
+ t->owner = (transport_smart *)owner;
+ t->parent.action = _ssh_action;
+ t->parent.close = _ssh_close;
+ t->parent.free = _ssh_free;
+
+ *out = (git_smart_subtransport *) t;
+ return 0;
+#else
+ GIT_UNUSED(owner);
+ GIT_UNUSED(param);
+
+ GIT_ASSERT_ARG(out);
+ *out = NULL;
+
+ git_error_set(GIT_ERROR_INVALID, "cannot create SSH transport. Library was built without SSH support");
+ return -1;
+#endif
+}
+
+int git_transport_ssh_with_paths(git_transport **out, git_remote *owner, void *payload)
+{
+#ifdef GIT_SSH
+ git_strarray *paths = (git_strarray *) payload;
+ git_transport *transport;
+ transport_smart *smart;
+ ssh_subtransport *t;
+ int error;
+ git_smart_subtransport_definition ssh_definition = {
+ git_smart_subtransport_ssh,
+ 0, /* no RPC */
+ NULL,
+ };
+
+ if (paths->count != 2) {
+ git_error_set(GIT_ERROR_SSH, "invalid ssh paths, must be two strings");
+ return GIT_EINVALIDSPEC;
+ }
+
+ if ((error = git_transport_smart(&transport, owner, &ssh_definition)) < 0)
+ return error;
+
+ smart = (transport_smart *) transport;
+ t = (ssh_subtransport *) smart->wrapped;
+
+ t->cmd_uploadpack = git__strdup(paths->strings[0]);
+ GIT_ERROR_CHECK_ALLOC(t->cmd_uploadpack);
+ t->cmd_receivepack = git__strdup(paths->strings[1]);
+ GIT_ERROR_CHECK_ALLOC(t->cmd_receivepack);
+
+ *out = transport;
+ return 0;
+#else
+ GIT_UNUSED(owner);
+ GIT_UNUSED(payload);
+
+ GIT_ASSERT_ARG(out);
+ *out = NULL;
+
+ git_error_set(GIT_ERROR_INVALID, "cannot create SSH transport. Library was built without SSH support");
+ return -1;
+#endif
+}
+
+#ifdef GIT_SSH
+static void shutdown_ssh(void)
+{
+ libssh2_exit();
+}
+#endif
+
+int git_transport_ssh_global_init(void)
+{
+#ifdef GIT_SSH
+ if (libssh2_init(0) < 0) {
+ git_error_set(GIT_ERROR_SSH, "unable to initialize libssh2");
+ return -1;
+ }
+
+ return git_runtime_shutdown_register(shutdown_ssh);
+
+#else
+
+ /* Nothing to initialize */
+ return 0;
+
+#endif
+}