/* packet-smtp.c * Routines for SMTP packet disassembly * * Copyright (c) 2000 by Richard Sharpe * * Added RFC 4954 SMTP Authentication * Michael Mann * Copyright 2012 * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1999 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include #include #include #include #include #include #include "packet-tls.h" #include "packet-tls-utils.h" /* RFC 2821 */ #define TCP_PORT_SMTP "25" #define TCP_PORT_SSL_SMTP 465 /* RFC 4409 */ #define TCP_PORT_SUBMISSION 587 void proto_register_smtp(void); void proto_reg_handoff_smtp(void); static int proto_smtp = -1; static int hf_smtp_req = -1; static int hf_smtp_rsp = -1; static int hf_smtp_message = -1; static int hf_smtp_command_line = -1; static int hf_smtp_req_command = -1; static int hf_smtp_req_parameter = -1; static int hf_smtp_response = -1; static int hf_smtp_rsp_code = -1; static int hf_smtp_rsp_parameter = -1; static int hf_smtp_username = -1; static int hf_smtp_password = -1; static int hf_smtp_username_password = -1; static int hf_smtp_eom = -1; static int hf_smtp_data_fragments = -1; static int hf_smtp_data_fragment = -1; static int hf_smtp_data_fragment_overlap = -1; static int hf_smtp_data_fragment_overlap_conflicts = -1; static int hf_smtp_data_fragment_multiple_tails = -1; static int hf_smtp_data_fragment_too_long_fragment = -1; static int hf_smtp_data_fragment_error = -1; static int hf_smtp_data_fragment_count = -1; static int hf_smtp_data_reassembled_in = -1; static int hf_smtp_data_reassembled_length = -1; static int ett_smtp = -1; static int ett_smtp_cmdresp = -1; static gint ett_smtp_data_fragment = -1; static gint ett_smtp_data_fragments = -1; static expert_field ei_smtp_base64_decode = EI_INIT; static gboolean smtp_auth_parameter_decoding_enabled = FALSE; /* desegmentation of SMTP command and response lines */ static gboolean smtp_desegment = TRUE; static gboolean smtp_data_desegment = TRUE; static reassembly_table smtp_data_reassembly_table; static const fragment_items smtp_data_frag_items = { /* Fragment subtrees */ &ett_smtp_data_fragment, &ett_smtp_data_fragments, /* Fragment fields */ &hf_smtp_data_fragments, &hf_smtp_data_fragment, &hf_smtp_data_fragment_overlap, &hf_smtp_data_fragment_overlap_conflicts, &hf_smtp_data_fragment_multiple_tails, &hf_smtp_data_fragment_too_long_fragment, &hf_smtp_data_fragment_error, &hf_smtp_data_fragment_count, /* Reassembled in field */ &hf_smtp_data_reassembled_in, /* Reassembled length field */ &hf_smtp_data_reassembled_length, /* Reassembled data field */ NULL, /* Tag */ "DATA fragments" }; static dissector_handle_t smtp_handle; static dissector_handle_t tls_handle; static dissector_handle_t imf_handle; static dissector_handle_t ntlmssp_handle; static dissector_handle_t data_text_lines_handle; /* * A CMD is an SMTP command, MESSAGE is the message portion, and EOM is the * last part of a message */ #define SMTP_PDU_CMD 0 #define SMTP_PDU_MESSAGE 1 #define SMTP_PDU_EOM 2 struct smtp_proto_data { guint16 pdu_type; guint16 conversation_id; gboolean more_frags; }; /* * State information stored with a conversation. */ typedef enum { SMTP_STATE_READING_CMDS, /* reading commands */ SMTP_STATE_READING_DATA, /* reading message data */ SMTP_STATE_AWAITING_STARTTLS_RESPONSE /* sent STARTTLS, awaiting response */ } smtp_state_t; typedef enum { SMTP_AUTH_STATE_NONE, /* No authentication seen or used */ SMTP_AUTH_STATE_START, /* Authentication started, waiting for username */ SMTP_AUTH_STATE_USERNAME_REQ, /* Received username request from server */ SMTP_AUTH_STATE_USERNAME_RSP, /* Received username response from client */ SMTP_AUTH_STATE_PASSWORD_REQ, /* Received password request from server */ SMTP_AUTH_STATE_PASSWORD_RSP, /* Received password request from server */ SMTP_AUTH_STATE_PLAIN_START_REQ, /* Received AUTH PLAIN command from client*/ SMTP_AUTH_STATE_PLAIN_CRED_REQ, /* Received AUTH PLAIN command including creds from client*/ SMTP_AUTH_STATE_PLAIN_REQ, /* Received AUTH PLAIN request from server */ SMTP_AUTH_STATE_PLAIN_RSP, /* Received AUTH PLAIN response from client */ SMTP_AUTH_STATE_NTLM_REQ, /* Received ntlm negotiate request from client */ SMTP_AUTH_STATE_NTLM_CHALLANGE, /* Received ntlm challange request from server */ SMTP_AUTH_STATE_NTLM_RSP, /* Received ntlm auth request from client */ SMTP_AUTH_STATE_SUCCESS, /* Password received, authentication successful, start decoding */ SMTP_AUTH_STATE_FAILED /* authentication failed, no decoding */ } smtp_auth_state_t; struct smtp_session_state { smtp_state_t smtp_state; /* Current state */ smtp_auth_state_t auth_state; /* Current authentication state */ /* Values that need to be saved because state machine can't be used during tree dissection */ guint32 first_auth_frame; /* First frame involving authentication. */ guint32 username_frame; /* Frame containing client username */ guint32 password_frame; /* Frame containing client password */ guint32 last_auth_frame; /* Last frame involving authentication. */ gboolean crlf_seen; /* Have we seen a CRLF on the end of a packet */ gboolean data_seen; /* Have we seen a DATA command yet */ guint32 msg_read_len; /* Length of BDAT message read so far */ guint32 msg_tot_len; /* Total length of BDAT message */ gboolean msg_last; /* Is this the last BDAT chunk */ guint32 username_cmd_frame; /* AUTH command contains username */ guint32 user_pass_cmd_frame; /* AUTH command contains username and password */ guint32 user_pass_frame; /* Frame contains username and password */ guint32 ntlm_req_frame; /* Frame containing NTLM request */ guint32 ntlm_cha_frame; /* Frame containing NTLM challange. */ guint32 ntlm_rsp_frame; /* Frame containing NTLM response. */ }; /* * See * * http://support.microsoft.com/default.aspx?scid=kb;[LN];812455 * * for the Exchange extensions. */ static const struct { const char *command; int len; } commands[] = { { "STARTTLS", 8 }, /* RFC 2487 */ { "X-EXPS", 6 }, /* Microsoft Exchange */ { "X-LINK2STATE", 12 }, /* Microsoft Exchange */ { "XEXCH50", 7 } /* Microsoft Exchange */ }; #define NCOMMANDS (sizeof commands / sizeof commands[0]) /* The following were copied from RFC 2821 */ static const value_string response_codes_vs[] = { { 211, "System status, or system help reply" }, { 214, "Help message" }, { 220, " Service ready" }, { 221, " Service closing transmission channel" }, { 235, "Authentication successful" }, { 250, "Requested mail action okay, completed" }, { 251, "User not local; will forward to " }, { 252, "Cannot VRFY user, but will accept message and attempt delivery" }, { 334, "AUTH input" }, { 354, "Start mail input; end with ." }, { 421, " Service not available, closing transmission channel" }, { 432, "A password transition is needed" }, { 450, "Requested mail action not taken: mailbox unavailable" }, { 451, "Requested action aborted: local error in processing" }, { 452, "Requested action not taken: insufficient system storage" }, { 454, "Temporary authenticaion failed" }, { 500, "Syntax error, command unrecognized" }, { 501, "Syntax error in parameters or arguments" }, { 502, "Command not implemented" }, { 503, "Bad sequence of commands" }, { 504, "Command parameter not implemented" }, { 530, "Authentication required" }, { 534, "Authentication mechanism is too weak" }, { 535, "Authentication credentials invalid" }, { 538, "Encryption required for requested authentication mechanism" }, { 550, "Requested action not taken: mailbox unavailable" }, { 551, "User not local; please try " }, { 552, "Requested mail action aborted: exceeded storage allocation" }, { 553, "Requested action not taken: mailbox name not allowed" }, { 554, "Transaction failed" }, { 0, NULL } }; static value_string_ext response_codes_vs_ext = VALUE_STRING_EXT_INIT(response_codes_vs); static gboolean line_is_smtp_command(const guchar *command, int commandlen) { size_t i; /* * To quote RFC 821, "Command codes are four alphabetic * characters". * * However, there are some SMTP extensions that involve commands * longer than 4 characters and/or that contain non-alphabetic * characters; we treat them specially. * * XXX - should we just have a table of known commands? Or would * that fail to catch some extensions we don't know about? */ if (commandlen == 4 && g_ascii_isalpha(command[0]) && g_ascii_isalpha(command[1]) && g_ascii_isalpha(command[2]) && g_ascii_isalpha(command[3])) { /* standard 4-alphabetic command */ return TRUE; } /* * Check the list of non-4-alphabetic commands. */ for (i = 0; i < NCOMMANDS; i++) { if (commandlen == commands[i].len && g_ascii_strncasecmp(command, commands[i].command, commands[i].len) == 0) return TRUE; } return FALSE; } static void dissect_smtp_data(tvbuff_t *tvb, int offset, proto_tree *smtp_tree) { gint next_offset; if (smtp_tree) { while (tvb_offset_exists(tvb, offset)) { /* * Find the end of the line. */ tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE); /* * Put this line. */ proto_tree_add_item(smtp_tree, hf_smtp_message, tvb, offset, next_offset - offset, ENC_ASCII|ENC_NA); /* * Step to the next line. */ offset = next_offset; } } } static void dissect_ntlm_auth(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, const char *line) { tvbuff_t *ntlm_tvb; ntlm_tvb = base64_to_tvb(tvb, line); if(tvb_strneql(ntlm_tvb, 0, "NTLMSSP", 7) == 0) { add_new_data_source(pinfo, ntlm_tvb, "NTLMSSP Data"); call_dissector(ntlmssp_handle, ntlm_tvb, pinfo, tree); } } static void decode_plain_auth(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint a_offset, int a_linelen) { gint returncode; gint length_user1; gint length_user2; gint length_pass; guint8 *decrypt = NULL; proto_item *ti; gsize len = 0; decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, a_offset, a_linelen, ENC_ASCII); if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &len); decrypt[len] = 0; } returncode = (gint)len; if (returncode) { length_user1 = (gint)strlen(decrypt); if (returncode >= (length_user1 + 1)) { length_user2 = (gint)strlen(decrypt + length_user1 + 1); proto_tree_add_string(tree, hf_smtp_username, tvb, a_offset, a_linelen, decrypt + length_user1 + 1); col_append_fstr(pinfo->cinfo, COL_INFO, "User: %s", format_text(wmem_packet_scope(), decrypt + length_user1 + 1, length_user2)); if (returncode >= (length_user1 + 1 + length_user2 + 1)) { length_pass = (gint)strlen(decrypt + length_user1 + length_user2 + 2); proto_tree_add_string(tree, hf_smtp_password, tvb, a_offset, length_pass, decrypt + length_user1 + length_user2 + 2); col_append_str(pinfo->cinfo, COL_INFO, " "); col_append_fstr(pinfo->cinfo, COL_INFO, " Pass: %s", format_text(wmem_packet_scope(), decrypt + length_user1 + length_user2 + 2, length_pass)); } } } } else { ti = proto_tree_add_item(tree, hf_smtp_username_password, tvb, a_offset, a_linelen, ENC_ASCII|ENC_NA); expert_add_info(pinfo, ti, &ei_smtp_base64_decode); col_append_str(pinfo->cinfo, COL_INFO, format_text(wmem_packet_scope(), decrypt, a_linelen)); } } static int dissect_smtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { struct smtp_proto_data *spd_frame_data; proto_tree *smtp_tree = NULL; proto_tree *cmdresp_tree = NULL; proto_item *ti, *hidden_item; int offset = 0; int request = 0; conversation_t *conversation; struct smtp_session_state *session_state; const guchar *line, *linep, *lineend; guint32 code; int linelen = 0; gint length_remaining; gboolean eom_seen = FALSE; gint next_offset; gint loffset = 0; int cmdlen; fragment_head *frag_msg = NULL; tvbuff_t *next_tvb; guint8 *decrypt = NULL; gsize decrypt_len = 0; guint8 *base64_string = NULL; guint8 line_code[3]; /* As there is no guarantee that we will only see frames in the * the SMTP conversation once, and that we will see them in * order - in Wireshark, the user could randomly click on frames * in the conversation in any order in which they choose - we * have to store information with each frame indicating whether * it contains commands or data or an EOM indication. * * XXX - what about frames that contain *both*? TCP is a * byte-stream protocol, and there are no guarantees that * TCP segment boundaries will correspond to SMTP commands * or EOM indications. * * We only need that for the client->server stream; responses * are easy to manage. * * If we have per frame data, use that, else, we must be on the first * pass, so we figure it out on the first pass. */ /* * Find or create the conversation for this. */ conversation = find_or_create_conversation(pinfo); /* * Is there a request structure attached to this conversation? */ session_state = (struct smtp_session_state *)conversation_get_proto_data(conversation, proto_smtp); if (!session_state) { /* * No - create one and attach it. */ session_state = (struct smtp_session_state *)wmem_alloc0(wmem_file_scope(), sizeof(struct smtp_session_state)); session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_NONE; session_state->msg_last = TRUE; conversation_add_proto_data(conversation, proto_smtp, session_state); } /* Is this a request or a response? */ request = pinfo->destport == pinfo->match_uint; /* * Is there any data attached to this frame? */ spd_frame_data = (struct smtp_proto_data *)p_get_proto_data(wmem_file_scope(), pinfo, proto_smtp, 0); if (!spd_frame_data) { /* * No frame data. */ if (request) { /* * Create a frame data structure and attach it to the packet. */ spd_frame_data = (struct smtp_proto_data *)wmem_alloc0(wmem_file_scope(), sizeof(struct smtp_proto_data)); spd_frame_data->conversation_id = conversation->conv_index; spd_frame_data->more_frags = TRUE; p_add_proto_data(wmem_file_scope(), pinfo, proto_smtp, 0, spd_frame_data); } /* * Get the first line from the buffer. * * Note that "tvb_find_line_end()" will, if it doesn't return * -1, return a value that is not longer than what's in the buffer, * and "tvb_find_line_end()" will always return a value that is not * longer than what's in the buffer, so the "tvb_get_ptr()" call * won't throw an exception. */ loffset = offset; while (tvb_offset_exists(tvb, loffset)) { linelen = tvb_find_line_end(tvb, loffset, -1, &next_offset, smtp_desegment && pinfo->can_desegment); if (linelen == -1) { if (offset == loffset) { /* * We didn't find a line ending, and we're doing desegmentation; * tell the TCP dissector where the data for this message starts * in the data it handed us, and tell it we need more bytes */ pinfo->desegment_offset = loffset; pinfo->desegment_len = DESEGMENT_ONE_MORE_SEGMENT; return tvb_captured_length(tvb); } else { linelen = tvb_reported_length_remaining(tvb, loffset); next_offset = loffset + linelen; } } /* * Check whether or not this packet is an end of message packet * We should look for CRLF.CRLF and they may be split. * We have to keep in mind that we may see what we want on * two passes through here ... */ if (session_state->smtp_state == SMTP_STATE_READING_DATA) { /* * The order of these is important ... We want to avoid * cases where there is a CRLF at the end of a packet and a * .CRLF at the beginning of the same packet. */ if ((session_state->crlf_seen && tvb_strneql(tvb, loffset, ".\r\n", 3) == 0) || tvb_strneql(tvb, loffset, "\r\n.\r\n", 5) == 0) eom_seen = TRUE; length_remaining = tvb_captured_length_remaining(tvb, loffset); if (length_remaining == tvb_reported_length_remaining(tvb, loffset) && tvb_strneql(tvb, loffset + length_remaining - 2, "\r\n", 2) == 0) session_state->crlf_seen = TRUE; else session_state->crlf_seen = FALSE; } /* * OK, Check if we have seen a DATA request. We do it here for * simplicity, but we have to be careful below. */ if (request) { if (session_state->smtp_state == SMTP_STATE_READING_DATA) { /* * This is message data. */ if (eom_seen) { /* Seen the EOM */ /* * EOM. * Everything that comes after it is commands. */ spd_frame_data->pdu_type = SMTP_PDU_EOM; session_state->smtp_state = SMTP_STATE_READING_CMDS; break; } else { /* * Message data with no EOM. */ spd_frame_data->pdu_type = SMTP_PDU_MESSAGE; if (session_state->msg_tot_len > 0) { /* * We are handling a BDAT message. * Check if we have reached end of the data chunk. */ session_state->msg_read_len += tvb_reported_length_remaining(tvb, loffset); /* * Since we're grabbing the rest of the packet, update the offset accordingly */ next_offset = tvb_reported_length(tvb); if (session_state->msg_read_len == session_state->msg_tot_len) { /* * We have reached end of BDAT data chunk. * Everything that comes after this is commands. */ session_state->smtp_state = SMTP_STATE_READING_CMDS; if (session_state->msg_last) { /* * We have found the LAST data chunk. * The message can now be reassembled. */ spd_frame_data->more_frags = FALSE; } break; /* no need to go through the remaining lines */ } } } } else { /* * This is commands - unless the capture started in the * middle of a session, and we're in the middle of data. * * Commands are not necessarily 4 characters; look * for a space or the end of the line to see where * the putative command ends. */ if ((session_state->auth_state != SMTP_AUTH_STATE_NONE) && (pinfo->num >= session_state->first_auth_frame) && ((session_state->last_auth_frame == 0) || (pinfo->num <= session_state->last_auth_frame))) { decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); if ((smtp_auth_parameter_decoding_enabled) && (strlen(decrypt) > 1) && (g_base64_decode_inplace(decrypt, &decrypt_len)) && (decrypt_len > 0)) { decrypt[decrypt_len] = 0; line = decrypt; linelen = (int)decrypt_len; } else { line = tvb_get_ptr(tvb, loffset, linelen); decrypt_len = linelen; } } else { line = tvb_get_ptr(tvb, loffset, linelen); } linep = line; lineend = line + linelen; while (linep < lineend && *linep != ' ') linep++; cmdlen = (int)(linep - line); if (line_is_smtp_command(line, cmdlen)) { if (g_ascii_strncasecmp(line, "DATA", 4) == 0) { /* * DATA command. * This is a command, but everything that comes after it, * until an EOM, is data. */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_DATA; session_state->data_seen = TRUE; } else if (g_ascii_strncasecmp(line, "BDAT", 4) == 0) { /* * BDAT command. * This is a command, but everything that comes after it, * until given length is received, is data. */ guint32 msg_len; msg_len = (guint32)strtoul (line+5, NULL, 10); spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->data_seen = TRUE; session_state->msg_tot_len += msg_len; if (msg_len == 0) { /* No data to read, next will be a command */ session_state->smtp_state = SMTP_STATE_READING_CMDS; } else { session_state->smtp_state = SMTP_STATE_READING_DATA; } if (g_ascii_strncasecmp(line+linelen-4, "LAST", 4) == 0) { /* * This is the last data chunk. */ session_state->msg_last = TRUE; if (msg_len == 0) { /* * No more data to expect. * The message can now be reassembled. */ spd_frame_data->more_frags = FALSE; } } else { session_state->msg_last = FALSE; } } else if ((g_ascii_strncasecmp(line, "AUTH LOGIN", 10) == 0) && (linelen <= 11)) { /* * AUTH LOGIN command. * Username is in a separate frame */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_START; session_state->first_auth_frame = pinfo->num; } else if ((g_ascii_strncasecmp(line, "AUTH LOGIN", 10) == 0) && (linelen > 11)) { /* * AUTH LOGIN command. * Username follows the 'AUTH LOGIN' string */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_USERNAME_RSP; session_state->first_auth_frame = pinfo->num; session_state->username_cmd_frame = pinfo->num; } else if ((g_ascii_strncasecmp(line, "AUTH PLAIN", 10) == 0) && (linelen <= 11)) { /* * AUTH PLAIN command. * Username and Password is in one separate frame */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_PLAIN_START_REQ; session_state->first_auth_frame = pinfo->num; } else if ((g_ascii_strncasecmp(line, "AUTH PLAIN", 10) == 0) && (linelen > 11)) { /* * AUTH PLAIN command. * Username and Password follows the 'AUTH PLAIN' string */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_PLAIN_CRED_REQ; session_state->first_auth_frame = pinfo->num; session_state->user_pass_cmd_frame = pinfo->num; } else if ((g_ascii_strncasecmp(line, "AUTH NTLM", 9) == 0) && (linelen > 10)) { /* * AUTH NTLM command with nlmssp request */ spd_frame_data->pdu_type = SMTP_PDU_CMD; session_state->smtp_state = SMTP_STATE_READING_CMDS; session_state->auth_state = SMTP_AUTH_STATE_NTLM_REQ; session_state->ntlm_req_frame = pinfo->num; } else if (g_ascii_strncasecmp(line, "STARTTLS", 8) == 0) { /* * STARTTLS command. * This is a command, but if the response is 220, * everything after the response is TLS. */ session_state->smtp_state = SMTP_STATE_AWAITING_STARTTLS_RESPONSE; spd_frame_data->pdu_type = SMTP_PDU_CMD; } else { /* * Regular command. */ spd_frame_data->pdu_type = SMTP_PDU_CMD; } } else if (session_state->auth_state == SMTP_AUTH_STATE_USERNAME_REQ) { session_state->auth_state = SMTP_AUTH_STATE_USERNAME_RSP; session_state->username_frame = pinfo->num; } else if (session_state->auth_state == SMTP_AUTH_STATE_PASSWORD_REQ) { session_state->auth_state = SMTP_AUTH_STATE_PASSWORD_RSP; session_state->password_frame = pinfo->num; } else if (session_state->auth_state == SMTP_AUTH_STATE_PLAIN_REQ) { session_state->auth_state = SMTP_AUTH_STATE_PLAIN_RSP; session_state->user_pass_frame = pinfo->num; } else if (session_state->auth_state == SMTP_AUTH_STATE_NTLM_CHALLANGE) { session_state->auth_state = SMTP_AUTH_STATE_NTLM_RSP; session_state->ntlm_rsp_frame = pinfo->num; } else { /* * Assume it's message data. */ spd_frame_data->pdu_type = session_state->data_seen ? SMTP_PDU_MESSAGE : SMTP_PDU_CMD; } } } /* * Step past this line. */ loffset = next_offset; } } /* * From here, we simply add items to the tree and info to the info * fields ... */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "SMTP"); col_clear(pinfo->cinfo, COL_INFO); if (tree) { /* Build the tree info ... */ ti = proto_tree_add_item(tree, proto_smtp, tvb, offset, -1, ENC_NA); smtp_tree = proto_item_add_subtree(ti, ett_smtp); } if (request) { /* * Check out whether or not we can see a command in there ... * What we are looking for is not data_seen and the word DATA * and not eom_seen. * * We will see DATA and session_state->data_seen when we process the * tree view after we have seen a DATA packet when processing * the packet list pane. * * On the first pass, we will not have any info on the packets * On second and subsequent passes, we will. */ switch (spd_frame_data->pdu_type) { case SMTP_PDU_MESSAGE: /* Column Info */ length_remaining = tvb_reported_length_remaining(tvb, offset); col_set_str(pinfo->cinfo, COL_INFO, smtp_data_desegment ? "C: DATA fragment" : "C: Message Body"); col_append_fstr(pinfo->cinfo, COL_INFO, ", %d byte%s", length_remaining, plurality (length_remaining, "", "s")); if (smtp_data_desegment) { frag_msg = fragment_add_seq_next(&smtp_data_reassembly_table, tvb, 0, pinfo, spd_frame_data->conversation_id, NULL, tvb_reported_length(tvb), spd_frame_data->more_frags); /* Show the text lines within this PDU fragment */ call_dissector(data_text_lines_handle, tvb, pinfo, smtp_tree); } else { /* * Message body. * Put its lines into the protocol tree, a line at a time. */ dissect_smtp_data(tvb, offset, smtp_tree); } break; case SMTP_PDU_EOM: /* * End-of-message-body indicator. * * XXX - what about stuff after the first line? * Unlikely, as the client should wait for a response to the * DATA command this terminates before sending another * request, but we should probably handle it. */ col_set_str(pinfo->cinfo, COL_INFO, "C: ."); proto_tree_add_none_format(smtp_tree, hf_smtp_eom, tvb, offset, linelen, "C: ."); if (smtp_data_desegment) { /* add final data segment */ if (loffset) fragment_add_seq_next(&smtp_data_reassembly_table, tvb, 0, pinfo, spd_frame_data->conversation_id, NULL, loffset, spd_frame_data->more_frags); /* terminate the desegmentation */ frag_msg = fragment_end_seq_next(&smtp_data_reassembly_table, pinfo, spd_frame_data->conversation_id, NULL); } break; case SMTP_PDU_CMD: /* * Command. * * XXX - what about stuff after the first line? * Unlikely, as the client should wait for a response to the * previous command before sending another request, but we * should probably handle it. */ loffset = offset; while (tvb_offset_exists(tvb, loffset)) { /* * Find the end of the line. */ linelen = tvb_find_line_end(tvb, loffset, -1, &next_offset, FALSE); /* Column Info */ if (loffset == offset) col_append_str(pinfo->cinfo, COL_INFO, "C: "); else col_append_str(pinfo->cinfo, COL_INFO, " | "); hidden_item = proto_tree_add_boolean(smtp_tree, hf_smtp_req, tvb, 0, 0, TRUE); PROTO_ITEM_SET_HIDDEN(hidden_item); if (session_state->username_frame == pinfo->num) { if (decrypt == NULL) { /* This line wasn't already decrypted through the state machine */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &decrypt_len); decrypt[decrypt_len] = 0; } else { decrypt_len = 0; } if (decrypt_len == 0) { /* Go back to the original string */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; } } } proto_tree_add_string(smtp_tree, hf_smtp_username, tvb, loffset, linelen, decrypt); col_append_fstr(pinfo->cinfo, COL_INFO, "User: %s", format_text(wmem_packet_scope(), decrypt, decrypt_len)); } else if (session_state->password_frame == pinfo->num) { if (decrypt == NULL) { /* This line wasn't already decrypted through the state machine */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &decrypt_len); decrypt[decrypt_len] = 0; } else { decrypt_len = 0; } if (decrypt_len == 0) { /* Go back to the original string */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; } } } proto_tree_add_string(smtp_tree, hf_smtp_password, tvb, loffset, linelen, decrypt); col_append_fstr(pinfo->cinfo, COL_INFO, "Pass: %s", format_text(wmem_packet_scope(), decrypt, decrypt_len)); } else if (session_state->ntlm_rsp_frame == pinfo->num) { decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &decrypt_len); decrypt[decrypt_len] = 0; } else { decrypt_len = 0; } if (decrypt_len == 0) { /* Go back to the original string */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); decrypt_len = linelen; col_append_str(pinfo->cinfo, COL_INFO, format_text(wmem_packet_scope(), decrypt, linelen)); proto_tree_add_item(smtp_tree, hf_smtp_command_line, tvb, loffset, linelen, ENC_ASCII|ENC_NA); } else { base64_string = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset, linelen, ENC_ASCII); dissect_ntlm_auth(tvb, pinfo, smtp_tree, base64_string); } } else { col_append_str(pinfo->cinfo, COL_INFO, format_text(wmem_packet_scope(), decrypt, linelen)); proto_tree_add_item(smtp_tree, hf_smtp_command_line, tvb, loffset, linelen, ENC_ASCII|ENC_NA); } } else if (session_state->user_pass_frame == pinfo->num) { decode_plain_auth(tvb, pinfo, smtp_tree, loffset, linelen); } else { if (linelen >= 4) cmdlen = 4; else cmdlen = linelen; /* * Put the command line into the protocol tree. */ ti = proto_tree_add_item(smtp_tree, hf_smtp_command_line, tvb, loffset, next_offset - loffset, ENC_ASCII|ENC_NA); cmdresp_tree = proto_item_add_subtree(ti, ett_smtp_cmdresp); proto_tree_add_item(cmdresp_tree, hf_smtp_req_command, tvb, loffset, cmdlen, ENC_ASCII|ENC_NA); if ((linelen > 5) && (session_state->username_cmd_frame == pinfo->num) ) { proto_tree_add_item(cmdresp_tree, hf_smtp_req_parameter, tvb, loffset + 5, linelen - 5, ENC_ASCII|ENC_NA); if (linelen >= 11) { if (decrypt == NULL) { /* This line wasn't already decrypted through the state machine */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 11, linelen - 11, ENC_ASCII); decrypt_len = linelen - 11; if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &decrypt_len); decrypt[decrypt_len] = 0; } else { decrypt_len = 0; } if (decrypt_len == 0) { /* Go back to the original string */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 11, linelen - 11, ENC_ASCII); decrypt_len = linelen - 11; } } } proto_tree_add_string(cmdresp_tree, hf_smtp_username, tvb, loffset + 11, linelen - 11, decrypt); col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, 11)); col_append_fstr(pinfo->cinfo, COL_INFO, "User: %s", format_text(wmem_packet_scope(), decrypt, decrypt_len)); } } else if ((linelen > 5) && (session_state->ntlm_req_frame == pinfo->num) ) { proto_tree_add_item(cmdresp_tree, hf_smtp_req_parameter, tvb, loffset + 5, linelen - 5, ENC_ASCII|ENC_NA); if (linelen >= 10) { decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 10, linelen - 10, ENC_ASCII); decrypt_len = linelen - 10; if (smtp_auth_parameter_decoding_enabled) { if (strlen(decrypt) > 1) { g_base64_decode_inplace(decrypt, &decrypt_len); decrypt[decrypt_len] = 0; } else { decrypt_len = 0; } if (decrypt_len == 0) { /* Go back to the original string */ decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 10, linelen - 10, ENC_ASCII); decrypt_len = linelen - 10; col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, 10)); col_append_str(pinfo->cinfo, COL_INFO, format_text(wmem_packet_scope(), decrypt, linelen - 10)); } else { base64_string = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 10, linelen - 10, ENC_ASCII); col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, 10)); dissect_ntlm_auth(tvb, pinfo, cmdresp_tree, format_text(wmem_packet_scope(), base64_string, linelen - 10)); } } else { col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, 10)); col_append_str(pinfo->cinfo, COL_INFO, format_text(wmem_packet_scope(), decrypt, linelen - 10)); } } } else if ((linelen > 5) && (session_state->user_pass_cmd_frame == pinfo->num) ) { proto_tree_add_item(cmdresp_tree, hf_smtp_req_parameter, tvb, loffset + 5, linelen - 5, ENC_ASCII|ENC_NA); col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, 11)); decode_plain_auth(tvb, pinfo, cmdresp_tree, loffset + 11, linelen - 11); } else if (linelen > 5) { proto_tree_add_item(cmdresp_tree, hf_smtp_req_parameter, tvb, loffset + 5, linelen - 5, ENC_ASCII|ENC_NA); col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, linelen)); } else { col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, loffset, linelen)); } if (smtp_data_desegment && !spd_frame_data->more_frags) { /* terminate the desegmentation */ frag_msg = fragment_end_seq_next(&smtp_data_reassembly_table, pinfo, spd_frame_data->conversation_id, NULL); } } /* * Step past this line. */ loffset = next_offset; } } if (smtp_data_desegment) { next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled SMTP", frag_msg, &smtp_data_frag_items, NULL, smtp_tree); if (next_tvb) { /* XXX: this is presumptuous - we may have negotiated something else */ if (imf_handle) { call_dissector(imf_handle, next_tvb, pinfo, tree); } else { /* * Message body. * Put its lines into the protocol tree, a line at a time. */ dissect_smtp_data(tvb, offset, smtp_tree); } pinfo->fragmented = FALSE; } else { pinfo->fragmented = TRUE; } } } else { /* * Process the response, a line at a time, until we hit a line * that doesn't have a continuation indication on it. */ if (tree) { hidden_item = proto_tree_add_boolean(smtp_tree, hf_smtp_rsp, tvb, 0, 0, TRUE); PROTO_ITEM_SET_HIDDEN(hidden_item); } loffset = offset; while (tvb_offset_exists(tvb, offset)) { /* * Find the end of the line. */ linelen = tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE); if (loffset == offset) col_append_str(pinfo->cinfo, COL_INFO, "S: "); else col_append_str(pinfo->cinfo, COL_INFO, " | "); if (tree) { /* * Put it into the protocol tree. */ ti = proto_tree_add_item(smtp_tree, hf_smtp_response, tvb, offset, next_offset - offset, ENC_ASCII|ENC_NA); cmdresp_tree = proto_item_add_subtree(ti, ett_smtp_cmdresp); } else cmdresp_tree = NULL; if (linelen >= 3) { line_code[0] = tvb_get_guint8(tvb, offset); line_code[1] = tvb_get_guint8(tvb, offset+1); line_code[2] = tvb_get_guint8(tvb, offset+2); if (g_ascii_isdigit(line_code[0]) && g_ascii_isdigit(line_code[1]) && g_ascii_isdigit(line_code[2])) { /* * We have a 3-digit response code. */ code = (line_code[0] - '0')*100 + (line_code[1] - '0')*10 + (line_code[2] - '0'); /* * If we're awaiting the response to a STARTTLS code, this * is it - if it's 220, all subsequent traffic will * be TLS, otherwise we're back to boring old SMTP. */ if (session_state->smtp_state == SMTP_STATE_AWAITING_STARTTLS_RESPONSE) { if (code == 220) { /* This is the last non-TLS frame. */ ssl_starttls_ack(tls_handle, pinfo, smtp_handle); } session_state->smtp_state = SMTP_STATE_READING_CMDS; } if (code == 334) { switch(session_state->auth_state) { case SMTP_AUTH_STATE_START: session_state->auth_state = SMTP_AUTH_STATE_USERNAME_REQ; break; case SMTP_AUTH_STATE_USERNAME_RSP: session_state->auth_state = SMTP_AUTH_STATE_PASSWORD_REQ; break; case SMTP_AUTH_STATE_PLAIN_REQ: session_state->auth_state = SMTP_AUTH_STATE_PLAIN_RSP; break; case SMTP_AUTH_STATE_PLAIN_START_REQ: session_state->auth_state = SMTP_AUTH_STATE_PLAIN_REQ; break; case SMTP_AUTH_STATE_NTLM_REQ: session_state->auth_state = SMTP_AUTH_STATE_NTLM_CHALLANGE; break; case SMTP_AUTH_STATE_NONE: case SMTP_AUTH_STATE_USERNAME_REQ: case SMTP_AUTH_STATE_PASSWORD_REQ: case SMTP_AUTH_STATE_PASSWORD_RSP: case SMTP_AUTH_STATE_PLAIN_RSP: case SMTP_AUTH_STATE_PLAIN_CRED_REQ: case SMTP_AUTH_STATE_NTLM_RSP: case SMTP_AUTH_STATE_NTLM_CHALLANGE: case SMTP_AUTH_STATE_SUCCESS: case SMTP_AUTH_STATE_FAILED: /* ignore */ break; } } else if ((session_state->auth_state == SMTP_AUTH_STATE_PASSWORD_RSP) || ( session_state->auth_state == SMTP_AUTH_STATE_PLAIN_RSP) || ( session_state->auth_state == SMTP_AUTH_STATE_NTLM_RSP) || ( session_state->auth_state == SMTP_AUTH_STATE_PLAIN_CRED_REQ) ) { if (code == 235) { session_state->auth_state = SMTP_AUTH_STATE_SUCCESS; } else { session_state->auth_state = SMTP_AUTH_STATE_FAILED; } session_state->last_auth_frame = pinfo->num; } /* * Put the response code and parameters into the protocol tree. */ proto_tree_add_uint(cmdresp_tree, hf_smtp_rsp_code, tvb, offset, 3, code); decrypt = NULL; if (linelen >= 4) { if ((smtp_auth_parameter_decoding_enabled) && (code == 334)) { decrypt = tvb_get_string_enc(wmem_packet_scope(), tvb, offset + 4, linelen - 4, ENC_ASCII); if (strlen(decrypt) > 1 && (g_base64_decode_inplace(decrypt, &decrypt_len)) && decrypt_len > 0) { decrypt[decrypt_len] = 0; if (g_ascii_strncasecmp(decrypt, "NTLMSSP", 7) == 0) { base64_string = tvb_get_string_enc(wmem_packet_scope(), tvb, loffset + 4, linelen - 4, ENC_ASCII); col_append_fstr(pinfo->cinfo, COL_INFO, "%d ", code); proto_tree_add_string(cmdresp_tree, hf_smtp_rsp_parameter, tvb, offset + 4, linelen - 4, (const char*)base64_string); dissect_ntlm_auth(tvb, pinfo, cmdresp_tree, base64_string); } else { proto_tree_add_string(cmdresp_tree, hf_smtp_rsp_parameter, tvb, offset + 4, linelen - 4, (const char*)decrypt); col_append_fstr(pinfo->cinfo, COL_INFO, "%d %s", code, format_text(wmem_packet_scope(), decrypt, decrypt_len)); } } else { decrypt = NULL; } } if (decrypt == NULL) { proto_tree_add_item(cmdresp_tree, hf_smtp_rsp_parameter, tvb, offset + 4, linelen - 4, ENC_ASCII|ENC_NA); col_append_fstr(pinfo->cinfo, COL_INFO, "%s", tvb_format_text(tvb, offset, linelen)); } } else { col_append_str(pinfo->cinfo, COL_INFO, tvb_format_text(tvb, offset, linelen)); } } } /* * Step past this line. */ offset = next_offset; } } return tvb_captured_length(tvb); } /* Register all the bits needed by the filtering engine */ void proto_register_smtp(void) { static hf_register_info hf[] = { { &hf_smtp_req, { "Request", "smtp.req", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_rsp, { "Response", "smtp.rsp", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_message, { "Message", "smtp.message", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_command_line, { "Command Line", "smtp.command_line", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_req_command, { "Command", "smtp.req.command", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_req_parameter, { "Request parameter", "smtp.req.parameter", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_response, { "Response", "smtp.response", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_rsp_code, { "Response code", "smtp.response.code", FT_UINT32, BASE_DEC|BASE_EXT_STRING, &response_codes_vs_ext, 0x0, NULL, HFILL }}, { &hf_smtp_rsp_parameter, { "Response parameter", "smtp.rsp.parameter", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_username, { "Username", "smtp.auth.username", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_password, { "Password", "smtp.auth.password", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_username_password, { "Username/Password", "smtp.auth.username_password", FT_STRING, BASE_NONE, NULL, 0x0, NULL, HFILL }}, { &hf_smtp_eom, { "EOM", "smtp.eom", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, /* Fragment entries */ { &hf_smtp_data_fragments, { "DATA fragments", "smtp.data.fragments", FT_NONE, BASE_NONE, NULL, 0x00, "Message fragments", HFILL } }, { &hf_smtp_data_fragment, { "DATA fragment", "smtp.data.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x00, "Message fragment", HFILL } }, { &hf_smtp_data_fragment_overlap, { "DATA fragment overlap", "smtp.data.fragment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Message fragment overlap", HFILL } }, { &hf_smtp_data_fragment_overlap_conflicts, { "DATA fragment overlapping with conflicting data", "smtp.data.fragment.overlap.conflicts", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Message fragment overlapping with conflicting data", HFILL } }, { &hf_smtp_data_fragment_multiple_tails, { "DATA has multiple tail fragments", "smtp.data.fragment.multiple_tails", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Message has multiple tail fragments", HFILL } }, { &hf_smtp_data_fragment_too_long_fragment, { "DATA fragment too long", "smtp.data.fragment.too_long_fragment", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "Message fragment too long", HFILL } }, { &hf_smtp_data_fragment_error, { "DATA defragmentation error", "smtp.data.fragment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x00, "Message defragmentation error", HFILL } }, { &hf_smtp_data_fragment_count, { "DATA fragment count", "smtp.data.fragment.count", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_smtp_data_reassembled_in, { "Reassembled DATA in frame", "smtp.data.reassembled.in", FT_FRAMENUM, BASE_NONE, NULL, 0x00, "This DATA fragment is reassembled in this frame", HFILL } }, { &hf_smtp_data_reassembled_length, { "Reassembled DATA length", "smtp.data.reassembled.length", FT_UINT32, BASE_DEC, NULL, 0x00, "The total length of the reassembled payload", HFILL } }, }; static gint *ett[] = { &ett_smtp, &ett_smtp_cmdresp, &ett_smtp_data_fragment, &ett_smtp_data_fragments, }; static ei_register_info ei[] = { { &ei_smtp_base64_decode, { "smtp.base64_decode", PI_PROTOCOL, PI_WARN, "base64 decode failed or is not enabled (check SMTP preferences)", EXPFILL }}, }; module_t *smtp_module; expert_module_t* expert_smtp; proto_smtp = proto_register_protocol("Simple Mail Transfer Protocol", "SMTP", "smtp"); proto_register_field_array(proto_smtp, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); expert_smtp = expert_register_protocol(proto_smtp); expert_register_field_array(expert_smtp, ei, array_length(ei)); reassembly_table_register(&smtp_data_reassembly_table, &addresses_ports_reassembly_table_functions); /* Allow dissector to find be found by name. */ smtp_handle = register_dissector("smtp", dissect_smtp, proto_smtp); /* Preferences */ smtp_module = prefs_register_protocol(proto_smtp, NULL); prefs_register_bool_preference(smtp_module, "desegment_lines", "Reassemble SMTP command and response lines spanning multiple TCP segments", "Whether the SMTP dissector should reassemble command and response lines" " spanning multiple TCP segments. To use this option, you must also enable " "\"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.", &smtp_desegment); prefs_register_bool_preference(smtp_module, "desegment_data", "Reassemble SMTP DATA commands spanning multiple TCP segments", "Whether the SMTP dissector should reassemble DATA command and lines" " spanning multiple TCP segments. To use this option, you must also enable " "\"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.", &smtp_data_desegment); prefs_register_bool_preference(smtp_module, "decryption", "Decode Base64 encoded AUTH parameters", "Whether the SMTP dissector should decode Base64 encoded AUTH parameters", &smtp_auth_parameter_decoding_enabled); } /* The registration hand-off routine */ void proto_reg_handoff_smtp(void) { dissector_add_uint_range_with_preference("tcp.port", TCP_PORT_SMTP, smtp_handle); ssl_dissector_add(TCP_PORT_SSL_SMTP, smtp_handle); /* No "auto" preference since handle is shared with SMTP */ dissector_add_uint("tcp.port", TCP_PORT_SUBMISSION, smtp_handle); /* find the IMF dissector */ imf_handle = find_dissector_add_dependency("imf", proto_smtp); /* find the TLS dissector */ tls_handle = find_dissector_add_dependency("tls", proto_smtp); /* find the NTLM dissector */ ntlmssp_handle = find_dissector_add_dependency("ntlmssp", proto_smtp); /* find the data-text-lines dissector */ data_text_lines_handle = find_dissector_add_dependency("data-text-lines", proto_smtp); } /* * Editor modelines - http://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 2 * tab-width: 8 * indent-tabs-mode: nil * End: * * vi: set shiftwidth=2 tabstop=8 expandtab: * :indentSize=2:tabSize=8:noTabs=true */