diff options
Diffstat (limited to 'src/libgit2/transports/ssh.c')
| -rw-r--r-- | src/libgit2/transports/ssh.c | 1110 |
1 files changed, 18 insertions, 1092 deletions
diff --git a/src/libgit2/transports/ssh.c b/src/libgit2/transports/ssh.c index 5500ea100..bef0b1440 100644 --- a/src/libgit2/transports/ssh.c +++ b/src/libgit2/transports/ssh.c @@ -5,1086 +5,38 @@ * a Linking Exception. For full terms see the included COPYING file. */ -#include "ssh.h" +#include "ssh_libssh2.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 "sysdir.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) { - rc = LIBSSH2_ERROR_AUTHENTICATION_FAILED; - 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; -} - -#define SSH_DIR ".ssh" -#define KNOWN_HOSTS_FILE "known_hosts" - -/* - * Load the known_hosts file. - * - * Returns success but leaves the output NULL if we couldn't find the file. - */ -static int load_known_hosts(LIBSSH2_KNOWNHOSTS **hosts, LIBSSH2_SESSION *session) -{ - git_str path = GIT_STR_INIT, sshdir = GIT_STR_INIT; - LIBSSH2_KNOWNHOSTS *known_hosts = NULL; - int error; - - GIT_ASSERT_ARG(hosts); - - if ((error = git_sysdir_expand_homedir_file(&sshdir, SSH_DIR)) < 0 || - (error = git_str_joinpath(&path, git_str_cstr(&sshdir), KNOWN_HOSTS_FILE)) < 0) - goto out; - - if ((known_hosts = libssh2_knownhost_init(session)) == NULL) { - ssh_error(session, "error initializing known hosts"); - error = -1; - goto out; - } - - /* - * Try to read the file and consider not finding it as not trusting the - * host rather than an error. - */ - error = libssh2_knownhost_readfile(known_hosts, git_str_cstr(&path), LIBSSH2_KNOWNHOST_FILE_OPENSSH); - if (error == LIBSSH2_ERROR_FILE) - error = 0; - if (error < 0) - ssh_error(session, "error reading known_hosts"); - -out: - *hosts = known_hosts; - - git_str_dispose(&sshdir); - git_str_dispose(&path); - - return error; -} - -static void add_hostkey_pref_if_avail( - LIBSSH2_KNOWNHOSTS *known_hosts, - const char *hostname, - int port, - git_str *prefs, - int type, - const char *type_name) -{ - struct libssh2_knownhost *host = NULL; - const char key = '\0'; - int mask = LIBSSH2_KNOWNHOST_TYPE_PLAIN | LIBSSH2_KNOWNHOST_KEYENC_RAW | type; - int error; - - error = libssh2_knownhost_checkp(known_hosts, hostname, port, &key, 1, mask, &host); - if (error == LIBSSH2_KNOWNHOST_CHECK_MISMATCH) { - if (git_str_len(prefs) > 0) { - git_str_putc(prefs, ','); - } - git_str_puts(prefs, type_name); - } -} - -/* - * We figure out what kind of key we want to ask the remote for by trying to - * look it up with a nonsense key and using that mismatch to figure out what key - * we do have stored for the host. - * - * Populates prefs with the string to pass to libssh2_session_method_pref. - */ -static void find_hostkey_preference( - LIBSSH2_KNOWNHOSTS *known_hosts, - const char *hostname, - int port, - git_str *prefs) -{ - /* - * The order here is important as it indicates the priority of what will - * be preferred. - */ -#ifdef LIBSSH2_KNOWNHOST_KEY_ED25519 - add_hostkey_pref_if_avail(known_hosts, hostname, port, prefs, LIBSSH2_KNOWNHOST_KEY_ED25519, "ssh-ed25519"); -#endif -#ifdef LIBSSH2_KNOWNHOST_KEY_ECDSA_256 - add_hostkey_pref_if_avail(known_hosts, hostname, port, prefs, LIBSSH2_KNOWNHOST_KEY_ECDSA_256, "ecdsa-sha2-nistp256"); - add_hostkey_pref_if_avail(known_hosts, hostname, port, prefs, LIBSSH2_KNOWNHOST_KEY_ECDSA_384, "ecdsa-sha2-nistp384"); - add_hostkey_pref_if_avail(known_hosts, hostname, port, prefs, LIBSSH2_KNOWNHOST_KEY_ECDSA_521, "ecdsa-sha2-nistp521"); -#endif - add_hostkey_pref_if_avail(known_hosts, hostname, port, prefs, LIBSSH2_KNOWNHOST_KEY_SSHRSA, "ssh-rsa"); -} - -static int _git_ssh_session_create( - LIBSSH2_SESSION **session, - LIBSSH2_KNOWNHOSTS **hosts, - const char *hostname, - int port, - git_stream *io) -{ - git_socket_stream *socket = GIT_CONTAINER_OF(io, git_socket_stream, parent); - LIBSSH2_SESSION *s; - LIBSSH2_KNOWNHOSTS *known_hosts; - git_str prefs = GIT_STR_INIT; - int rc = 0; - - GIT_ASSERT_ARG(session); - GIT_ASSERT_ARG(hosts); - - s = libssh2_session_init(); - if (!s) { - git_error_set(GIT_ERROR_NET, "failed to initialize SSH session"); - return -1; - } - - if ((rc = load_known_hosts(&known_hosts, s)) < 0) { - ssh_error(s, "error loading known_hosts"); - libssh2_session_free(s); - return -1; - } - - find_hostkey_preference(known_hosts, hostname, port, &prefs); - if (git_str_len(&prefs) > 0) { - do { - rc = libssh2_session_method_pref(s, LIBSSH2_METHOD_HOSTKEY, git_str_cstr(&prefs)); - } while (LIBSSH2_ERROR_EAGAIN == rc || LIBSSH2_ERROR_TIMEOUT == rc); - if (rc != LIBSSH2_ERROR_NONE) { - ssh_error(s, "failed to set hostkey preference"); - goto on_error; - } - } - git_str_dispose(&prefs); - - 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"); - goto on_error; - } - - libssh2_session_set_blocking(s, 1); - - *session = s; - *hosts = known_hosts; - - return 0; - -on_error: - libssh2_knownhost_free(known_hosts); - libssh2_session_free(s); - return -1; -} - - -/* - * Returns the typemask argument to pass to libssh2_knownhost_check{,p} based on - * the type of key that libssh2_session_hostkey returns. - */ -static int fingerprint_type_mask(int keytype) -{ - int mask = LIBSSH2_KNOWNHOST_TYPE_PLAIN | LIBSSH2_KNOWNHOST_KEYENC_RAW; - return mask; - - switch (keytype) { - case LIBSSH2_HOSTKEY_TYPE_RSA: - mask |= LIBSSH2_KNOWNHOST_KEY_SSHRSA; - break; - case LIBSSH2_HOSTKEY_TYPE_DSS: - mask |= LIBSSH2_KNOWNHOST_KEY_SSHDSS; - break; -#ifdef LIBSSH2_HOSTKEY_TYPE_ECDSA_256 - case LIBSSH2_HOSTKEY_TYPE_ECDSA_256: - mask |= LIBSSH2_KNOWNHOST_KEY_ECDSA_256; - break; - case LIBSSH2_HOSTKEY_TYPE_ECDSA_384: - mask |= LIBSSH2_KNOWNHOST_KEY_ECDSA_384; - break; - case LIBSSH2_HOSTKEY_TYPE_ECDSA_521: - mask |= LIBSSH2_KNOWNHOST_KEY_ECDSA_521; - break; -#endif -#ifdef LIBSSH2_HOSTKEY_TYPE_ED25519 - case LIBSSH2_HOSTKEY_TYPE_ED25519: - mask |= LIBSSH2_KNOWNHOST_KEY_ED25519; - break; -#endif - } - - return mask; -} - -/* - * Check the host against the user's known_hosts file. - * - * Returns 1/0 for valid/''not-valid or <0 for an error - */ -static int check_against_known_hosts( - LIBSSH2_SESSION *session, - LIBSSH2_KNOWNHOSTS *known_hosts, - const char *hostname, - int port, - const char *key, - size_t key_len, - int key_type) -{ - int check, typemask, ret = 0; - struct libssh2_knownhost *host = NULL; - - if (known_hosts == NULL) - return 0; - - typemask = fingerprint_type_mask(key_type); - check = libssh2_knownhost_checkp(known_hosts, hostname, port, key, key_len, typemask, &host); - if (check == LIBSSH2_KNOWNHOST_CHECK_FAILURE) { - ssh_error(session, "error checking for known host"); - return -1; - } - - ret = check == LIBSSH2_KNOWNHOST_CHECK_MATCH ? 1 : 0; - - return ret; -} - -/* - * Perform the check for the session's certificate against known hosts if - * possible and then ask the user if they have a callback. - * - * Returns 1/0 for valid/not-valid or <0 for an error - */ -static int check_certificate( - LIBSSH2_SESSION *session, - LIBSSH2_KNOWNHOSTS *known_hosts, - git_transport_certificate_check_cb check_cb, - void *check_cb_payload, - const char *host, - int port) -{ - git_cert_hostkey cert = {{ 0 }}; - const char *key; - size_t cert_len; - int cert_type, cert_valid = 0, error = 0; - - if ((key = libssh2_session_hostkey(session, &cert_len, &cert_type)) == NULL) { - ssh_error(session, "failed to retrieve hostkey"); - return -1; - } - - if ((cert_valid = check_against_known_hosts(session, known_hosts, host, port, key, cert_len, cert_type)) < 0) - return -1; - - cert.parent.cert_type = GIT_CERT_HOSTKEY_LIBSSH2; - 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"); - return -1; - } - - git_error_clear(); - error = 0; - if (!cert_valid) { - git_error_set(GIT_ERROR_SSH, "invalid or unknown remote ssh hostkey"); - error = GIT_ECERTIFICATE; - } - - if (check_cb != NULL) { - git_cert_hostkey *cert_ptr = &cert; - git_error_state previous_error = {0}; - - git_error_state_capture(&previous_error, error); - error = check_cb((git_cert *) cert_ptr, cert_valid, host, check_cb_payload); - if (error == GIT_PASSTHROUGH) { - error = git_error_state_restore(&previous_error); - } else if (error < 0 && !git_error_last()) { - git_error_set(GIT_ERROR_NET, "unknown remote host key"); - } - - git_error_state_free(&previous_error); - } - - return error; -} - -#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, port; - ssh_stream *s; - git_credential *cred = NULL; - LIBSSH2_SESSION *session=NULL; - LIBSSH2_CHANNEL *channel=NULL; - LIBSSH2_KNOWNHOSTS *known_hosts = 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 ((error = git_net_url_parse_standard_or_scp(&s->url, url)) < 0 || - (error = git_socket_stream_new(&s->io, s->url.host, s->url.port)) < 0 || - (error = git_stream_connect(s->io)) < 0) - goto done; - - /* - * Try to parse the port as a number, if we can't then fall back to - * default. It would be nice if we could get the port that was resolved - * as part of the stream connection, but that's not something that's - * exposed. - */ - if (git__strntol32(&port, s->url.port, strlen(s->url.port), NULL, 10) < 0) { - git_error_set(GIT_ERROR_NET, "invalid port to ssh: %s", s->url.port); - error = -1; - goto done; - } - - if ((error = _git_ssh_session_create(&session, &known_hosts, s->url.host, port, s->io)) < 0) - goto done; - - if ((error = check_certificate(session, known_hosts, t->owner->connect_opts.callbacks.certificate_check, t->owner->connect_opts.callbacks.payload, s->url.host, port)) < 0) - 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 (known_hosts) - libssh2_knownhost_free(known_hosts); - 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, "remote rejected authentication"); - 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 +#include "transports/smart.h" int git_smart_subtransport_ssh( - git_smart_subtransport **out, git_transport *owner, void *param) + 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; + return git_smart_subtransport_ssh_libssh2(out, owner, param); #else + GIT_UNUSED(out); 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) +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 */ @@ -1100,48 +52,22 @@ int git_transport_ssh_with_paths(git_transport **out, git_remote *owner, void *p 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); + if ((error = git_smart_subtransport_ssh_libssh2_set_paths( + (git_smart_subtransport *)smart->wrapped, + paths->strings[0], + paths->strings[1])) < 0) + return error; *out = transport; return 0; #else + GIT_UNUSED(out); 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 -} |