From 7b425e06f940fbc0a1d962bee7695530fcc70ceb Mon Sep 17 00:00:00 2001 From: George Hazan Date: Fri, 15 Mar 2019 16:04:01 +0300 Subject: libssh updated to 1.8.1 --- libs/libssh2/src/channel.c | 26 +++- libs/libssh2/src/comp.c | 9 +- libs/libssh2/src/kex.c | 24 ++++ libs/libssh2/src/packet.c | 25 ++-- libs/libssh2/src/session.c | 5 + libs/libssh2/src/sftp.c | 317 +++++++++++++++++++++++++++++++++++-------- libs/libssh2/src/transport.c | 26 +++- libs/libssh2/src/userauth.c | 55 ++++++-- 8 files changed, 405 insertions(+), 82 deletions(-) (limited to 'libs/libssh2/src') diff --git a/libs/libssh2/src/channel.c b/libs/libssh2/src/channel.c index 538a0ab0d9..39ff05bf13 100644 --- a/libs/libssh2/src/channel.c +++ b/libs/libssh2/src/channel.c @@ -238,7 +238,20 @@ _libssh2_channel_open(LIBSSH2_SESSION * session, const char *channel_type, goto channel_error; } + if(session->open_data_len < 1) { + _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + goto channel_error; + } + if (session->open_data[0] == SSH_MSG_CHANNEL_OPEN_CONFIRMATION) { + + if(session->open_data_len < 17) { + _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + goto channel_error; + } + session->open_channel->remote.id = _libssh2_ntohu32(session->open_data + 5); session->open_channel->local.window_size = @@ -518,7 +531,7 @@ channel_forward_listen(LIBSSH2_SESSION * session, const char *host, if (rc == LIBSSH2_ERROR_EAGAIN) { _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block"); return NULL; - } else if (rc) { + } else if (rc || data_len < 1) { _libssh2_error(session, LIBSSH2_ERROR_PROTO, "Unknown"); session->fwdLstn_state = libssh2_NB_state_idle; return NULL; @@ -855,6 +868,11 @@ static int channel_setenv(LIBSSH2_CHANNEL *channel, channel->setenv_state = libssh2_NB_state_idle; return rc; } + else if(data_len < 1) { + channel->setenv_state = libssh2_NB_state_idle; + return _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + } if (data[0] == SSH_MSG_CHANNEL_SUCCESS) { LIBSSH2_FREE(session, data); @@ -971,7 +989,7 @@ static int channel_request_pty(LIBSSH2_CHANNEL *channel, &channel->reqPTY_packet_requirev_state); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } else if (rc || data_len < 1) { channel->reqPTY_state = libssh2_NB_state_idle; return _libssh2_error(session, LIBSSH2_ERROR_PROTO, "Failed to require the PTY package"); @@ -1197,7 +1215,7 @@ channel_x11_req(LIBSSH2_CHANNEL *channel, int single_connection, &channel->reqX11_packet_requirev_state); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } else if (rc || data_len < 1) { channel->reqX11_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "waiting for x11-req response packet"); @@ -1324,7 +1342,7 @@ _libssh2_channel_process_startup(LIBSSH2_CHANNEL *channel, &channel->process_packet_requirev_state); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } else if (rc || data_len < 1) { channel->process_state = libssh2_NB_state_end; return _libssh2_error(session, rc, "Failed waiting for channel success"); diff --git a/libs/libssh2/src/comp.c b/libs/libssh2/src/comp.c index 4560188bb7..6293195907 100644 --- a/libs/libssh2/src/comp.c +++ b/libs/libssh2/src/comp.c @@ -224,7 +224,12 @@ comp_method_zlib_decomp(LIBSSH2_SESSION * session, /* A short-term alloc of a full data chunk is better than a series of reallocs */ char *out; - int out_maxlen = 4 * src_len; + size_t out_maxlen = src_len; + + if (src_len <= SIZE_MAX / 4) + out_maxlen = src_len * 4; + else + out_maxlen = payload_limit; /* If strm is null, then we have not yet been initialized. */ if (strm == NULL) @@ -271,7 +276,7 @@ comp_method_zlib_decomp(LIBSSH2_SESSION * session, "decompression failure"); } - if (out_maxlen >= (int) payload_limit) { + if (out_maxlen > (int) payload_limit || out_maxlen > SIZE_MAX / 2) { LIBSSH2_FREE(session, out); return _libssh2_error(session, LIBSSH2_ERROR_ZLIB, "Excessive growth in decompression phase"); diff --git a/libs/libssh2/src/kex.c b/libs/libssh2/src/kex.c index 65b722f421..3634cb5a91 100644 --- a/libs/libssh2/src/kex.c +++ b/libs/libssh2/src/kex.c @@ -228,11 +228,23 @@ static int diffie_hellman_sha1(LIBSSH2_SESSION *session, } /* Parse KEXDH_REPLY */ + if(exchange_state->s_packet_len < 5) { + ret = _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet length"); + goto clean_exit; + } + exchange_state->s = exchange_state->s_packet + 1; session->server_hostkey_len = _libssh2_ntohu32(exchange_state->s); exchange_state->s += 4; + if(session->server_hostkey_len > exchange_state->s_packet_len - 5) { + ret = _libssh2_error(session, LIBSSH2_ERROR_OUT_OF_BOUNDARY, + "Host key length out of bounds"); + goto clean_exit; + } + if (session->server_hostkey) LIBSSH2_FREE(session, session->server_hostkey); @@ -848,11 +860,23 @@ static int diffie_hellman_sha256(LIBSSH2_SESSION *session, } /* Parse KEXDH_REPLY */ + if(exchange_state->s_packet_len < 5) { + ret = _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet length"); + goto clean_exit; + } + exchange_state->s = exchange_state->s_packet + 1; session->server_hostkey_len = _libssh2_ntohu32(exchange_state->s); exchange_state->s += 4; + if(session->server_hostkey_len > exchange_state->s_packet_len - 5) { + ret = _libssh2_error(session, LIBSSH2_ERROR_OUT_OF_BOUNDARY, + "Host key length out of bounds"); + goto clean_exit; + } + if (session->server_hostkey) LIBSSH2_FREE(session, session->server_hostkey); diff --git a/libs/libssh2/src/packet.c b/libs/libssh2/src/packet.c index 5f1feb8c6b..c950b5dcfa 100644 --- a/libs/libssh2/src/packet.c +++ b/libs/libssh2/src/packet.c @@ -775,8 +775,8 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data, uint32_t len = _libssh2_ntohu32(data + 5); unsigned char want_reply = 1; - if(len < (datalen - 10)) - want_reply = data[9 + len]; + if((len + 9) < datalen) + want_reply = data[len + 9]; _libssh2_debug(session, LIBSSH2_TRACE_CONN, @@ -784,6 +784,7 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data, channel, len, data + 9, want_reply); if (len == sizeof("exit-status") - 1 + && (sizeof("exit-status") - 1 + 9) <= datalen && !memcmp("exit-status", data + 9, sizeof("exit-status") - 1)) { @@ -792,7 +793,7 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data, channelp = _libssh2_channel_locate(session, channel); - if (channelp) { + if (channelp && (sizeof("exit-status") + 13) <= datalen) { channelp->exit_status = _libssh2_ntohu32(data + 9 + sizeof("exit-status")); _libssh2_debug(session, LIBSSH2_TRACE_CONN, @@ -805,24 +806,32 @@ _libssh2_packet_add(LIBSSH2_SESSION * session, unsigned char *data, } else if (len == sizeof("exit-signal") - 1 + && (sizeof("exit-signal") - 1 + 9) <= datalen && !memcmp("exit-signal", data + 9, sizeof("exit-signal") - 1)) { /* command terminated due to signal */ if(datalen >= 20) channelp = _libssh2_channel_locate(session, channel); - if (channelp) { + if (channelp && (sizeof("exit-signal") + 13) <= datalen) { /* set signal name (without SIG prefix) */ uint32_t namelen = _libssh2_ntohu32(data + 9 + sizeof("exit-signal")); - channelp->exit_signal = - LIBSSH2_ALLOC(session, namelen + 1); + + if(namelen <= UINT_MAX - 1) { + channelp->exit_signal = + LIBSSH2_ALLOC(session, namelen + 1); + } + else { + channelp->exit_signal = NULL; + } + if (!channelp->exit_signal) rc = _libssh2_error(session, LIBSSH2_ERROR_ALLOC, "memory for signal name"); - else { + else if ((sizeof("exit-signal") + 13 + namelen <= datalen)) { memcpy(channelp->exit_signal, - data + 13 + sizeof("exit_signal"), namelen); + data + 13 + sizeof("exit-signal"), namelen); channelp->exit_signal[namelen] = '\0'; /* TODO: save error message and language tag */ _libssh2_debug(session, LIBSSH2_TRACE_CONN, diff --git a/libs/libssh2/src/session.c b/libs/libssh2/src/session.c index 6352d12ee7..b5a83ddd67 100644 --- a/libs/libssh2/src/session.c +++ b/libs/libssh2/src/session.c @@ -765,6 +765,11 @@ session_startup(LIBSSH2_SESSION *session, libssh2_socket_t sock) if (rc) return rc; + if(session->startup_data_len < 5) { + return _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet length"); + } + session->startup_service_length = _libssh2_ntohu32(session->startup_data + 1); diff --git a/libs/libssh2/src/sftp.c b/libs/libssh2/src/sftp.c index 7c44116401..fd94d39029 100644 --- a/libs/libssh2/src/sftp.c +++ b/libs/libssh2/src/sftp.c @@ -204,6 +204,10 @@ sftp_packet_add(LIBSSH2_SFTP *sftp, unsigned char *data, LIBSSH2_SFTP_PACKET *packet; uint32_t request_id; + if (data_len < 5) { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } + _libssh2_debug(session, LIBSSH2_TRACE_SFTP, "Received packet type %d (len %d)", (int) data[0], data_len); @@ -345,6 +349,10 @@ sftp_packet_read(LIBSSH2_SFTP *sftp) return _libssh2_error(session, LIBSSH2_ERROR_CHANNEL_PACKET_EXCEEDED, "SFTP packet too large"); + if (sftp->partial_len == 0) + return _libssh2_error(session, + LIBSSH2_ERROR_ALLOC, + "Unable to allocate empty SFTP packet"); _libssh2_debug(session, LIBSSH2_TRACE_SFTP, "Data begin - Packet Length: %lu", @@ -504,11 +512,15 @@ sftp_packet_ask(LIBSSH2_SFTP *sftp, unsigned char packet_type, static int sftp_packet_require(LIBSSH2_SFTP *sftp, unsigned char packet_type, uint32_t request_id, unsigned char **data, - size_t *data_len) + size_t *data_len, size_t required_size) { LIBSSH2_SESSION *session = sftp->channel->session; int rc; + if (data == NULL || data_len == NULL || required_size == 0) { + return LIBSSH2_ERROR_BAD_USE; + } + _libssh2_debug(session, LIBSSH2_TRACE_SFTP, "Requiring packet %d id %ld", (int) packet_type, request_id); @@ -516,6 +528,11 @@ sftp_packet_require(LIBSSH2_SFTP *sftp, unsigned char packet_type, /* The right packet was available in the packet brigade */ _libssh2_debug(session, LIBSSH2_TRACE_SFTP, "Got %d", (int) packet_type); + + if (*data_len < required_size) { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } + return LIBSSH2_ERROR_NONE; } @@ -529,6 +546,11 @@ sftp_packet_require(LIBSSH2_SFTP *sftp, unsigned char packet_type, /* The right packet was available in the packet brigade */ _libssh2_debug(session, LIBSSH2_TRACE_SFTP, "Got %d", (int) packet_type); + + if (*data_len < required_size) { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } + return LIBSSH2_ERROR_NONE; } } @@ -544,11 +566,15 @@ static int sftp_packet_requirev(LIBSSH2_SFTP *sftp, int num_valid_responses, const unsigned char *valid_responses, uint32_t request_id, unsigned char **data, - size_t *data_len) + size_t *data_len, size_t required_size) { int i; int rc; + if (data == NULL || data_len == NULL || required_size == 0) { + return LIBSSH2_ERROR_BAD_USE; + } + /* If no timeout is active, start a new one */ if (sftp->requirev_start == 0) sftp->requirev_start = time(NULL); @@ -562,6 +588,11 @@ sftp_packet_requirev(LIBSSH2_SFTP *sftp, int num_valid_responses, * the timeout is not active */ sftp->requirev_start = 0; + + if (*data_len < required_size) { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } + return LIBSSH2_ERROR_NONE; } } @@ -636,36 +667,65 @@ sftp_attr2bin(unsigned char *p, const LIBSSH2_SFTP_ATTRIBUTES * attrs) /* sftp_bin2attr */ static int -sftp_bin2attr(LIBSSH2_SFTP_ATTRIBUTES * attrs, const unsigned char *p) +sftp_bin2attr(LIBSSH2_SFTP_ATTRIBUTES * attrs, const unsigned char *p, size_t data_len) { const unsigned char *s = p; - memset(attrs, 0, sizeof(LIBSSH2_SFTP_ATTRIBUTES)); - attrs->flags = _libssh2_ntohu32(s); - s += 4; + if (data_len >= 4) { + memset(attrs, 0, sizeof(LIBSSH2_SFTP_ATTRIBUTES)); + attrs->flags = _libssh2_ntohu32(s); + s += 4; + data_len -= 4; + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } if (attrs->flags & LIBSSH2_SFTP_ATTR_SIZE) { - attrs->filesize = _libssh2_ntohu64(s); - s += 8; + if (data_len >= 8) { + attrs->filesize = _libssh2_ntohu64(s); + s += 8; + data_len -= 8; + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } } if (attrs->flags & LIBSSH2_SFTP_ATTR_UIDGID) { - attrs->uid = _libssh2_ntohu32(s); - s += 4; - attrs->gid = _libssh2_ntohu32(s); - s += 4; + if (data_len >= 8) { + attrs->uid = _libssh2_ntohu32(s); + s += 4; + attrs->gid = _libssh2_ntohu32(s); + s += 4; + data_len -= 8; + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } } if (attrs->flags & LIBSSH2_SFTP_ATTR_PERMISSIONS) { - attrs->permissions = _libssh2_ntohu32(s); - s += 4; + if (data_len >= 4) { + attrs->permissions = _libssh2_ntohu32(s); + s += 4; + data_len -= 4; + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } } if (attrs->flags & LIBSSH2_SFTP_ATTR_ACMODTIME) { - attrs->atime = _libssh2_ntohu32(s); - s += 4; - attrs->mtime = _libssh2_ntohu32(s); - s += 4; + if (data_len >= 8) { + attrs->atime = _libssh2_ntohu32(s); + s += 4; + attrs->mtime = _libssh2_ntohu32(s); + s += 4; + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } } return (s - p); @@ -835,18 +895,23 @@ static LIBSSH2_SFTP *sftp_init(LIBSSH2_SESSION *session) } rc = sftp_packet_require(sftp_handle, SSH_FXP_VERSION, - 0, &data, &data_len); - if (rc == LIBSSH2_ERROR_EAGAIN) + 0, &data, &data_len, 5); + if (rc == LIBSSH2_ERROR_EAGAIN) { + _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, + "Would block receiving SSH_FXP_VERSION"); return NULL; - else if (rc) { - _libssh2_error(session, rc, - "Timeout waiting for response from SFTP subsystem"); - goto sftp_init_error; } - if (data_len < 5) { + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, "Invalid SSH_FXP_VERSION response"); - LIBSSH2_FREE(session, data); + goto sftp_init_error; + } + else if (rc) { + _libssh2_error(session, rc, + "Timeout waiting for response from SFTP subsystem"); goto sftp_init_error; } @@ -1112,12 +1177,20 @@ sftp_open(LIBSSH2_SFTP *sftp, const char *filename, { SSH_FXP_HANDLE, SSH_FXP_STATUS }; rc = sftp_packet_requirev(sftp, 2, fopen_responses, sftp->open_request_id, &data, - &data_len); + &data_len, 1); if (rc == LIBSSH2_ERROR_EAGAIN) { _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block waiting for status message"); return NULL; } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Response too small"); + return NULL; + } sftp->open_state = libssh2_NB_state_idle; if (rc) { _libssh2_error(session, rc, "Timeout waiting for status message"); @@ -1148,12 +1221,20 @@ sftp_open(LIBSSH2_SFTP *sftp, const char *filename, /* silly situation, but check for a HANDLE */ rc = sftp_packet_require(sftp, SSH_FXP_HANDLE, sftp->open_request_id, &data, - &data_len); + &data_len, 10); if(rc == LIBSSH2_ERROR_EAGAIN) { /* go back to sent state and wait for something else */ sftp->open_state = libssh2_NB_state_sent; return NULL; } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Too small FXP_HANDLE"); + return NULL; + } else if(!rc) /* we got the handle so this is not a bad situation */ badness = 0; @@ -1480,15 +1561,21 @@ static ssize_t sftp_read(LIBSSH2_SFTP_HANDLE * handle, char *buffer, } rc = sftp_packet_requirev(sftp, 2, read_responses, - chunk->request_id, &data, &data_len); - - if (rc==LIBSSH2_ERROR_EAGAIN && bytes_in_buffer != 0) { + chunk->request_id, &data, &data_len, 9); + if (rc == LIBSSH2_ERROR_EAGAIN && bytes_in_buffer != 0) { /* do not return EAGAIN if we have already * written data into the buffer */ return bytes_in_buffer; } - if (rc < 0) { + if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Response too small"); + } + else if(rc < 0) { sftp->read_state = libssh2_NB_state_sent2; return rc; } @@ -1698,7 +1785,7 @@ static ssize_t sftp_readdir(LIBSSH2_SFTP_HANDLE *handle, char *buffer, if (attrs) memset(attrs, 0, sizeof(LIBSSH2_SFTP_ATTRIBUTES)); - s += sftp_bin2attr(attrs ? attrs : &attrs_dummy, s); + s += sftp_bin2attr(attrs ? attrs : &attrs_dummy, s, 32); handle->u.dir.next_name = (char *) s; end: @@ -1753,9 +1840,16 @@ static ssize_t sftp_readdir(LIBSSH2_SFTP_HANDLE *handle, char *buffer, retcode = sftp_packet_requirev(sftp, 2, read_responses, sftp->readdir_request_id, &data, - &data_len); + &data_len, 9); if (retcode == LIBSSH2_ERROR_EAGAIN) return retcode; + else if (retcode == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Status message too short"); + } else if (retcode) { sftp->readdir_state = libssh2_NB_state_idle; return _libssh2_error(session, retcode, @@ -1981,8 +2075,15 @@ static ssize_t sftp_write(LIBSSH2_SFTP_HANDLE *handle, const char *buffer, /* we check the packets in order */ rc = sftp_packet_require(sftp, SSH_FXP_STATUS, - chunk->request_id, &data, &data_len); - if (rc < 0) { + chunk->request_id, &data, &data_len, 9); + if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "FXP write packet too short"); + } + else if (rc < 0) { if (rc == LIBSSH2_ERROR_EAGAIN) sftp->write_state = libssh2_NB_state_sent; return rc; @@ -2124,10 +2225,18 @@ static int sftp_fsync(LIBSSH2_SFTP_HANDLE *handle) } rc = sftp_packet_require(sftp, SSH_FXP_STATUS, - sftp->fsync_request_id, &data, &data_len); + sftp->fsync_request_id, &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP fsync packet too short"); + } + else if (rc) { sftp->fsync_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP EXTENDED REPLY"); @@ -2227,9 +2336,16 @@ static int sftp_fstat(LIBSSH2_SFTP_HANDLE *handle, rc = sftp_packet_requirev(sftp, 2, fstat_responses, sftp->fstat_request_id, &data, - &data_len); + &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) return rc; + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP fstat packet too short"); + } else if (rc) { sftp->fstat_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, @@ -2252,7 +2368,12 @@ static int sftp_fstat(LIBSSH2_SFTP_HANDLE *handle, } } - sftp_bin2attr(attrs, data + 5); + if (sftp_bin2attr(attrs, data + 5, data_len - 5) < 0) { + LIBSSH2_FREE(session, data); + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Attributes too short in SFTP fstat"); + } + LIBSSH2_FREE(session, data); return 0; @@ -2429,11 +2550,19 @@ sftp_close_handle(LIBSSH2_SFTP_HANDLE *handle) if (handle->close_state == libssh2_NB_state_sent) { rc = sftp_packet_require(sftp, SSH_FXP_STATUS, handle->close_request_id, &data, - &data_len); + &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + data = NULL; + _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Packet too short in FXP_CLOSE command"); + } + else if (rc) { _libssh2_error(session, rc, "Error waiting for status message"); } @@ -2547,10 +2676,17 @@ static int sftp_unlink(LIBSSH2_SFTP *sftp, const char *filename, rc = sftp_packet_require(sftp, SSH_FXP_STATUS, sftp->unlink_request_id, &data, - &data_len); + &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP unlink packet too short"); + } else if (rc) { sftp->unlink_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, @@ -2658,10 +2794,18 @@ static int sftp_rename(LIBSSH2_SFTP *sftp, const char *source_filename, rc = sftp_packet_require(sftp, SSH_FXP_STATUS, sftp->rename_request_id, &data, - &data_len); + &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP rename packet too short"); + } + else if (rc) { sftp->rename_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP STATUS"); @@ -2783,11 +2927,19 @@ static int sftp_fstatvfs(LIBSSH2_SFTP_HANDLE *handle, LIBSSH2_SFTP_STATVFS *st) } rc = sftp_packet_requirev(sftp, 2, responses, sftp->fstatvfs_request_id, - &data, &data_len); + &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP rename packet too short"); + } + else if (rc) { sftp->fstatvfs_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP EXTENDED REPLY"); @@ -2910,10 +3062,18 @@ static int sftp_statvfs(LIBSSH2_SFTP *sftp, const char *path, } rc = sftp_packet_requirev(sftp, 2, responses, sftp->statvfs_request_id, - &data, &data_len); + &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP fstat packet too short"); + } + else if (rc) { sftp->statvfs_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP EXTENDED REPLY"); @@ -3040,10 +3200,18 @@ static int sftp_mkdir(LIBSSH2_SFTP *sftp, const char *path, } rc = sftp_packet_require(sftp, SSH_FXP_STATUS, sftp->mkdir_request_id, - &data, &data_len); + &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP mkdir packet too short"); + } + else if (rc) { sftp->mkdir_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP STATUS"); @@ -3134,10 +3302,18 @@ static int sftp_rmdir(LIBSSH2_SFTP *sftp, const char *path, } rc = sftp_packet_require(sftp, SSH_FXP_STATUS, - sftp->rmdir_request_id, &data, &data_len); + sftp->rmdir_request_id, &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) { return rc; - } else if (rc) { + } + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP rmdir packet too short"); + } + else if (rc) { sftp->rmdir_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, "Error waiting for FXP STATUS"); @@ -3247,9 +3423,16 @@ static int sftp_stat(LIBSSH2_SFTP *sftp, const char *path, } rc = sftp_packet_requirev(sftp, 2, stat_responses, - sftp->stat_request_id, &data, &data_len); + sftp->stat_request_id, &data, &data_len, 9); if (rc == LIBSSH2_ERROR_EAGAIN) return rc; + else if (rc == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP stat packet too short"); + } else if (rc) { sftp->stat_state = libssh2_NB_state_idle; return _libssh2_error(session, rc, @@ -3273,7 +3456,12 @@ static int sftp_stat(LIBSSH2_SFTP *sftp, const char *path, } memset(attrs, 0, sizeof(LIBSSH2_SFTP_ATTRIBUTES)); - sftp_bin2attr(attrs, data + 5); + if (sftp_bin2attr(attrs, data + 5, data_len - 5) < 0) { + LIBSSH2_FREE(session, data); + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "Attributes too short in SFTP fstat"); + } + LIBSSH2_FREE(session, data); return 0; @@ -3378,9 +3566,16 @@ static int sftp_symlink(LIBSSH2_SFTP *sftp, const char *path, retcode = sftp_packet_requirev(sftp, 2, link_responses, sftp->symlink_request_id, &data, - &data_len); + &data_len, 9); if (retcode == LIBSSH2_ERROR_EAGAIN) return retcode; + else if (retcode == LIBSSH2_ERROR_OUT_OF_BOUNDARY) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP symlink packet too short"); + } else if (retcode) { sftp->symlink_state = libssh2_NB_state_idle; return _libssh2_error(session, retcode, @@ -3410,6 +3605,14 @@ static int sftp_symlink(LIBSSH2_SFTP *sftp, const char *path, "no name entries"); } + if (data_len < 13) { + if (data_len > 0) { + LIBSSH2_FREE(session, data); + } + return _libssh2_error(session, LIBSSH2_ERROR_SFTP_PROTOCOL, + "SFTP stat packet too short"); + } + /* this reads a u32 and stores it into a signed 32bit value */ link_len = _libssh2_ntohu32(data + 9); if (link_len < target_len) { diff --git a/libs/libssh2/src/transport.c b/libs/libssh2/src/transport.c index 8725da0950..7317579f36 100644 --- a/libs/libssh2/src/transport.c +++ b/libs/libssh2/src/transport.c @@ -438,6 +438,16 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session) return LIBSSH2_ERROR_DECRYPT; p->padding_length = block[4]; + if(p->packet_length < 1) { + return LIBSSH2_ERROR_DECRYPT; + } + else if(p->packet_length > LIBSSH2_PACKET_MAXPAYLOAD) { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } + else if ( p->padding_length > p->packet_length - 1 ) { + return LIBSSH2_ERROR_DECRYPT; + } + /* total_num is the number of bytes following the initial (5 bytes) packet length and padding length fields */ @@ -471,8 +481,12 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session) /* copy the data from index 5 to the end of the blocksize from the temporary buffer to the start of the decrypted buffer */ - memcpy(p->wptr, &block[5], blocksize - 5); - p->wptr += blocksize - 5; /* advance write pointer */ + if (blocksize - 5 <= total_num) { + memcpy(p->wptr, &block[5], blocksize - 5); + p->wptr += blocksize - 5; /* advance write pointer */ + } else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } } /* init the data_num field to the number of bytes of @@ -546,7 +560,13 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session) /* if there are bytes to copy that aren't decrypted, simply copy them as-is to the target buffer */ if (numbytes > 0) { - memcpy(p->wptr, &p->buf[p->readidx], numbytes); + + if (numbytes <= total_num - (p->wptr - p->payload)) { + memcpy(p->wptr, &p->buf[p->readidx], numbytes); + } + else { + return LIBSSH2_ERROR_OUT_OF_BOUNDARY; + } /* advance the read pointer */ p->readidx += numbytes; diff --git a/libs/libssh2/src/userauth.c b/libs/libssh2/src/userauth.c index cdfa25e663..ed804629d2 100644 --- a/libs/libssh2/src/userauth.c +++ b/libs/libssh2/src/userauth.c @@ -107,7 +107,7 @@ static char *userauth_list(LIBSSH2_SESSION *session, const char *username, LIBSSH2_FREE(session, session->userauth_list_data); session->userauth_list_data = NULL; - if (rc) { + if (rc || (session->userauth_list_data_len < 1)) { _libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND, "Unable to send userauth-none request"); session->userauth_list_state = libssh2_NB_state_idle; @@ -143,8 +143,20 @@ static char *userauth_list(LIBSSH2_SESSION *session, const char *username, return NULL; } - methods_len = _libssh2_ntohu32(session->userauth_list_data + 1); + if(session->userauth_list_data_len < 5) { + LIBSSH2_FREE(session, session->userauth_list_data); + session->userauth_list_data = NULL; + _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + return NULL; + } + methods_len = _libssh2_ntohu32(session->userauth_list_data + 1); + if(methods_len >= session->userauth_list_data_len - 5) { + _libssh2_error(session, LIBSSH2_ERROR_OUT_OF_BOUNDARY, + "Unexpected userauth list size"); + return NULL; + } /* Do note that the memory areas overlap! */ memmove(session->userauth_list_data, session->userauth_list_data + 5, methods_len); @@ -285,6 +297,11 @@ userauth_password(LIBSSH2_SESSION *session, return _libssh2_error(session, rc, "Waiting for password response"); } + else if(session->userauth_pswd_data_len < 1) { + session->userauth_pswd_state = libssh2_NB_state_idle; + return _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + } if (session->userauth_pswd_data[0] == SSH_MSG_USERAUTH_SUCCESS) { _libssh2_debug(session, LIBSSH2_TRACE_AUTH, @@ -312,6 +329,12 @@ userauth_password(LIBSSH2_SESSION *session, session->userauth_pswd_state = libssh2_NB_state_sent1; } + if(session->userauth_pswd_data_len < 1) { + session->userauth_pswd_state = libssh2_NB_state_idle; + return _libssh2_error(session, LIBSSH2_ERROR_PROTO, + "Unexpected packet size"); + } + if ((session->userauth_pswd_data[0] == SSH_MSG_USERAUTH_PASSWD_CHANGEREQ) || (session->userauth_pswd_data0 == @@ -976,7 +999,7 @@ userauth_hostbased_fromfile(LIBSSH2_SESSION *session, } session->userauth_host_state = libssh2_NB_state_idle; - if (rc) { + if (rc || data_len < 1) { return _libssh2_error(session, LIBSSH2_ERROR_PUBLICKEY_UNVERIFIED, "Auth failed"); } @@ -1149,7 +1172,7 @@ _libssh2_userauth_publickey(LIBSSH2_SESSION *session, NULL, 0); if (rc == LIBSSH2_ERROR_EAGAIN) return _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block"); - else if (rc) { + else if (rc || (session->userauth_pblc_data_len < 1)) { LIBSSH2_FREE(session, session->userauth_pblc_packet); session->userauth_pblc_packet = NULL; LIBSSH2_FREE(session, session->userauth_pblc_method); @@ -1332,7 +1355,7 @@ _libssh2_userauth_publickey(LIBSSH2_SESSION *session, if (rc == LIBSSH2_ERROR_EAGAIN) { return _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block requesting userauth list"); - } else if (rc) { + } else if (rc || session->userauth_pblc_data_len < 1) { session->userauth_pblc_state = libssh2_NB_state_idle; return _libssh2_error(session, LIBSSH2_ERROR_PUBLICKEY_UNVERIFIED, "Waiting for publickey USERAUTH response"); @@ -1654,7 +1677,7 @@ userauth_keyboard_interactive(LIBSSH2_SESSION * session, if (rc == LIBSSH2_ERROR_EAGAIN) { return _libssh2_error(session, LIBSSH2_ERROR_EAGAIN, "Would block"); - } else if (rc) { + } else if (rc || session->userauth_kybd_data_len < 1) { session->userauth_kybd_state = libssh2_NB_state_idle; return _libssh2_error(session, LIBSSH2_ERROR_AUTHENTICATION_FAILED, @@ -1734,6 +1757,13 @@ userauth_keyboard_interactive(LIBSSH2_SESSION * session, /* int num-prompts */ session->userauth_kybd_num_prompts = _libssh2_ntohu32(s); s += 4; + if(session->userauth_kybd_num_prompts && + session->userauth_kybd_num_prompts > 100) { + _libssh2_error(session, LIBSSH2_ERROR_OUT_OF_BOUNDARY, + "Too many replies for " + "keyboard-interactive prompts"); + goto cleanup; + } if(session->userauth_kybd_num_prompts) { session->userauth_kybd_prompts = @@ -1801,8 +1831,17 @@ userauth_keyboard_interactive(LIBSSH2_SESSION * session, for(i = 0; i < session->userauth_kybd_num_prompts; i++) { /* string response[1] (ISO-10646 UTF-8) */ - session->userauth_kybd_packet_len += - 4 + session->userauth_kybd_responses[i].length; + if(session->userauth_kybd_responses[i].length <= + (SIZE_MAX - 4 - session->userauth_kybd_packet_len) ) { + session->userauth_kybd_packet_len += + 4 + session->userauth_kybd_responses[i].length; + } + else { + _libssh2_error(session, LIBSSH2_ERROR_ALLOC, + "Unable to allocate memory for keyboard-" + "interactive response packet"); + goto cleanup; + } } /* A new userauth_kybd_data area is to be allocated, free the -- cgit v1.2.3