diff options
Diffstat (limited to 'Utilities/cmcurl/lib/telnet.c')
-rw-r--r-- | Utilities/cmcurl/lib/telnet.c | 1636 |
1 files changed, 1636 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/telnet.c b/Utilities/cmcurl/lib/telnet.c new file mode 100644 index 0000000000..e4ffd853ac --- /dev/null +++ b/Utilities/cmcurl/lib/telnet.c @@ -0,0 +1,1636 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at https://curl.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + * SPDX-License-Identifier: curl + * + ***************************************************************************/ + +#include "curl_setup.h" + +#ifndef CURL_DISABLE_TELNET + +#ifdef HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif +#ifdef HAVE_NETDB_H +#include <netdb.h> +#endif +#ifdef HAVE_ARPA_INET_H +#include <arpa/inet.h> +#endif +#ifdef HAVE_NET_IF_H +#include <net/if.h> +#endif +#ifdef HAVE_SYS_IOCTL_H +#include <sys/ioctl.h> +#endif + +#ifdef HAVE_SYS_PARAM_H +#include <sys/param.h> +#endif + +#include "urldata.h" +#include <curl/curl.h> +#include "transfer.h" +#include "sendf.h" +#include "telnet.h" +#include "connect.h" +#include "progress.h" +#include "system_win32.h" +#include "arpa_telnet.h" +#include "select.h" +#include "strcase.h" +#include "warnless.h" + +/* The last 3 #include files should be in this order */ +#include "curl_printf.h" +#include "curl_memory.h" +#include "memdebug.h" + +#define SUBBUFSIZE 512 + +#define CURL_SB_CLEAR(x) x->subpointer = x->subbuffer +#define CURL_SB_TERM(x) \ + do { \ + x->subend = x->subpointer; \ + CURL_SB_CLEAR(x); \ + } while(0) +#define CURL_SB_ACCUM(x,c) \ + do { \ + if(x->subpointer < (x->subbuffer + sizeof(x->subbuffer))) \ + *x->subpointer++ = (c); \ + } while(0) + +#define CURL_SB_GET(x) ((*x->subpointer++)&0xff) +#define CURL_SB_LEN(x) (x->subend - x->subpointer) + +/* For posterity: +#define CURL_SB_PEEK(x) ((*x->subpointer)&0xff) +#define CURL_SB_EOF(x) (x->subpointer >= x->subend) */ + +#ifdef CURL_DISABLE_VERBOSE_STRINGS +#define printoption(a,b,c,d) Curl_nop_stmt +#endif + +static +CURLcode telrcv(struct Curl_easy *data, + const unsigned char *inbuf, /* Data received from socket */ + ssize_t count); /* Number of bytes received */ + +#ifndef CURL_DISABLE_VERBOSE_STRINGS +static void printoption(struct Curl_easy *data, + const char *direction, + int cmd, int option); +#endif + +static void negotiate(struct Curl_easy *data); +static void send_negotiation(struct Curl_easy *data, int cmd, int option); +static void set_local_option(struct Curl_easy *data, + int option, int newstate); +static void set_remote_option(struct Curl_easy *data, + int option, int newstate); + +static void printsub(struct Curl_easy *data, + int direction, unsigned char *pointer, + size_t length); +static void suboption(struct Curl_easy *data); +static void sendsuboption(struct Curl_easy *data, int option); + +static CURLcode telnet_do(struct Curl_easy *data, bool *done); +static CURLcode telnet_done(struct Curl_easy *data, + CURLcode, bool premature); +static CURLcode send_telnet_data(struct Curl_easy *data, + char *buffer, ssize_t nread); + +/* For negotiation compliant to RFC 1143 */ +#define CURL_NO 0 +#define CURL_YES 1 +#define CURL_WANTYES 2 +#define CURL_WANTNO 3 + +#define CURL_EMPTY 0 +#define CURL_OPPOSITE 1 + +/* + * Telnet receiver states for fsm + */ +typedef enum +{ + CURL_TS_DATA = 0, + CURL_TS_IAC, + CURL_TS_WILL, + CURL_TS_WONT, + CURL_TS_DO, + CURL_TS_DONT, + CURL_TS_CR, + CURL_TS_SB, /* sub-option collection */ + CURL_TS_SE /* looking for sub-option end */ +} TelnetReceive; + +struct TELNET { + int please_negotiate; + int already_negotiated; + int us[256]; + int usq[256]; + int us_preferred[256]; + int him[256]; + int himq[256]; + int him_preferred[256]; + int subnegotiation[256]; + char subopt_ttype[32]; /* Set with suboption TTYPE */ + char subopt_xdisploc[128]; /* Set with suboption XDISPLOC */ + unsigned short subopt_wsx; /* Set with suboption NAWS */ + unsigned short subopt_wsy; /* Set with suboption NAWS */ + TelnetReceive telrcv_state; + struct curl_slist *telnet_vars; /* Environment variables */ + + /* suboptions */ + unsigned char subbuffer[SUBBUFSIZE]; + unsigned char *subpointer, *subend; /* buffer for sub-options */ +}; + + +/* + * TELNET protocol handler. + */ + +const struct Curl_handler Curl_handler_telnet = { + "TELNET", /* scheme */ + ZERO_NULL, /* setup_connection */ + telnet_do, /* do_it */ + telnet_done, /* done */ + ZERO_NULL, /* do_more */ + ZERO_NULL, /* connect_it */ + ZERO_NULL, /* connecting */ + ZERO_NULL, /* doing */ + ZERO_NULL, /* proto_getsock */ + ZERO_NULL, /* doing_getsock */ + ZERO_NULL, /* domore_getsock */ + ZERO_NULL, /* perform_getsock */ + ZERO_NULL, /* disconnect */ + ZERO_NULL, /* readwrite */ + ZERO_NULL, /* connection_check */ + ZERO_NULL, /* attach connection */ + PORT_TELNET, /* defport */ + CURLPROTO_TELNET, /* protocol */ + CURLPROTO_TELNET, /* family */ + PROTOPT_NONE | PROTOPT_NOURLQUERY /* flags */ +}; + + +static +CURLcode init_telnet(struct Curl_easy *data) +{ + struct TELNET *tn; + + tn = calloc(1, sizeof(struct TELNET)); + if(!tn) + return CURLE_OUT_OF_MEMORY; + + data->req.p.telnet = tn; /* make us known */ + + tn->telrcv_state = CURL_TS_DATA; + + /* Init suboptions */ + CURL_SB_CLEAR(tn); + + /* Set the options we want by default */ + tn->us_preferred[CURL_TELOPT_SGA] = CURL_YES; + tn->him_preferred[CURL_TELOPT_SGA] = CURL_YES; + + /* To be compliant with previous releases of libcurl + we enable this option by default. This behavior + can be changed thanks to the "BINARY" option in + CURLOPT_TELNETOPTIONS + */ + tn->us_preferred[CURL_TELOPT_BINARY] = CURL_YES; + tn->him_preferred[CURL_TELOPT_BINARY] = CURL_YES; + + /* We must allow the server to echo what we sent + but it is not necessary to request the server + to do so (it might forces the server to close + the connection). Hence, we ignore ECHO in the + negotiate function + */ + tn->him_preferred[CURL_TELOPT_ECHO] = CURL_YES; + + /* Set the subnegotiation fields to send information + just after negotiation passed (do/will) + + Default values are (0,0) initialized by calloc. + According to the RFC1013 it is valid: + A value equal to zero is acceptable for the width (or height), + and means that no character width (or height) is being sent. + In this case, the width (or height) that will be assumed by the + Telnet server is operating system specific (it will probably be + based upon the terminal type information that may have been sent + using the TERMINAL TYPE Telnet option). */ + tn->subnegotiation[CURL_TELOPT_NAWS] = CURL_YES; + return CURLE_OK; +} + +static void negotiate(struct Curl_easy *data) +{ + int i; + struct TELNET *tn = data->req.p.telnet; + + for(i = 0; i < CURL_NTELOPTS; i++) { + if(i == CURL_TELOPT_ECHO) + continue; + + if(tn->us_preferred[i] == CURL_YES) + set_local_option(data, i, CURL_YES); + + if(tn->him_preferred[i] == CURL_YES) + set_remote_option(data, i, CURL_YES); + } +} + +#ifndef CURL_DISABLE_VERBOSE_STRINGS +static void printoption(struct Curl_easy *data, + const char *direction, int cmd, int option) +{ + if(data->set.verbose) { + if(cmd == CURL_IAC) { + if(CURL_TELCMD_OK(option)) + infof(data, "%s IAC %s", direction, CURL_TELCMD(option)); + else + infof(data, "%s IAC %d", direction, option); + } + else { + const char *fmt = (cmd == CURL_WILL) ? "WILL" : + (cmd == CURL_WONT) ? "WONT" : + (cmd == CURL_DO) ? "DO" : + (cmd == CURL_DONT) ? "DONT" : 0; + if(fmt) { + const char *opt; + if(CURL_TELOPT_OK(option)) + opt = CURL_TELOPT(option); + else if(option == CURL_TELOPT_EXOPL) + opt = "EXOPL"; + else + opt = NULL; + + if(opt) + infof(data, "%s %s %s", direction, fmt, opt); + else + infof(data, "%s %s %d", direction, fmt, option); + } + else + infof(data, "%s %d %d", direction, cmd, option); + } + } +} +#endif + +static void send_negotiation(struct Curl_easy *data, int cmd, int option) +{ + unsigned char buf[3]; + ssize_t bytes_written; + struct connectdata *conn = data->conn; + + buf[0] = CURL_IAC; + buf[1] = (unsigned char)cmd; + buf[2] = (unsigned char)option; + + bytes_written = swrite(conn->sock[FIRSTSOCKET], buf, 3); + if(bytes_written < 0) { + int err = SOCKERRNO; + failf(data,"Sending data failed (%d)",err); + } + + printoption(data, "SENT", cmd, option); +} + +static +void set_remote_option(struct Curl_easy *data, int option, int newstate) +{ + struct TELNET *tn = data->req.p.telnet; + if(newstate == CURL_YES) { + switch(tn->him[option]) { + case CURL_NO: + tn->him[option] = CURL_WANTYES; + send_negotiation(data, CURL_DO, option); + break; + + case CURL_YES: + /* Already enabled */ + break; + + case CURL_WANTNO: + switch(tn->himq[option]) { + case CURL_EMPTY: + /* Already negotiating for CURL_YES, queue the request */ + tn->himq[option] = CURL_OPPOSITE; + break; + case CURL_OPPOSITE: + /* Error: already queued an enable request */ + break; + } + break; + + case CURL_WANTYES: + switch(tn->himq[option]) { + case CURL_EMPTY: + /* Error: already negotiating for enable */ + break; + case CURL_OPPOSITE: + tn->himq[option] = CURL_EMPTY; + break; + } + break; + } + } + else { /* NO */ + switch(tn->him[option]) { + case CURL_NO: + /* Already disabled */ + break; + + case CURL_YES: + tn->him[option] = CURL_WANTNO; + send_negotiation(data, CURL_DONT, option); + break; + + case CURL_WANTNO: + switch(tn->himq[option]) { + case CURL_EMPTY: + /* Already negotiating for NO */ + break; + case CURL_OPPOSITE: + tn->himq[option] = CURL_EMPTY; + break; + } + break; + + case CURL_WANTYES: + switch(tn->himq[option]) { + case CURL_EMPTY: + tn->himq[option] = CURL_OPPOSITE; + break; + case CURL_OPPOSITE: + break; + } + break; + } + } +} + +static +void rec_will(struct Curl_easy *data, int option) +{ + struct TELNET *tn = data->req.p.telnet; + switch(tn->him[option]) { + case CURL_NO: + if(tn->him_preferred[option] == CURL_YES) { + tn->him[option] = CURL_YES; + send_negotiation(data, CURL_DO, option); + } + else + send_negotiation(data, CURL_DONT, option); + + break; + + case CURL_YES: + /* Already enabled */ + break; + + case CURL_WANTNO: + switch(tn->himq[option]) { + case CURL_EMPTY: + /* Error: DONT answered by WILL */ + tn->him[option] = CURL_NO; + break; + case CURL_OPPOSITE: + /* Error: DONT answered by WILL */ + tn->him[option] = CURL_YES; + tn->himq[option] = CURL_EMPTY; + break; + } + break; + + case CURL_WANTYES: + switch(tn->himq[option]) { + case CURL_EMPTY: + tn->him[option] = CURL_YES; + break; + case CURL_OPPOSITE: + tn->him[option] = CURL_WANTNO; + tn->himq[option] = CURL_EMPTY; + send_negotiation(data, CURL_DONT, option); + break; + } + break; + } +} + +static +void rec_wont(struct Curl_easy *data, int option) +{ + struct TELNET *tn = data->req.p.telnet; + switch(tn->him[option]) { + case CURL_NO: + /* Already disabled */ + break; + + case CURL_YES: + tn->him[option] = CURL_NO; + send_negotiation(data, CURL_DONT, option); + break; + + case CURL_WANTNO: + switch(tn->himq[option]) { + case CURL_EMPTY: + tn->him[option] = CURL_NO; + break; + + case CURL_OPPOSITE: + tn->him[option] = CURL_WANTYES; + tn->himq[option] = CURL_EMPTY; + send_negotiation(data, CURL_DO, option); + break; + } + break; + + case CURL_WANTYES: + switch(tn->himq[option]) { + case CURL_EMPTY: + tn->him[option] = CURL_NO; + break; + case CURL_OPPOSITE: + tn->him[option] = CURL_NO; + tn->himq[option] = CURL_EMPTY; + break; + } + break; + } +} + +static void +set_local_option(struct Curl_easy *data, int option, int newstate) +{ + struct TELNET *tn = data->req.p.telnet; + if(newstate == CURL_YES) { + switch(tn->us[option]) { + case CURL_NO: + tn->us[option] = CURL_WANTYES; + send_negotiation(data, CURL_WILL, option); + break; + + case CURL_YES: + /* Already enabled */ + break; + + case CURL_WANTNO: + switch(tn->usq[option]) { + case CURL_EMPTY: + /* Already negotiating for CURL_YES, queue the request */ + tn->usq[option] = CURL_OPPOSITE; + break; + case CURL_OPPOSITE: + /* Error: already queued an enable request */ + break; + } + break; + + case CURL_WANTYES: + switch(tn->usq[option]) { + case CURL_EMPTY: + /* Error: already negotiating for enable */ + break; + case CURL_OPPOSITE: + tn->usq[option] = CURL_EMPTY; + break; + } + break; + } + } + else { /* NO */ + switch(tn->us[option]) { + case CURL_NO: + /* Already disabled */ + break; + + case CURL_YES: + tn->us[option] = CURL_WANTNO; + send_negotiation(data, CURL_WONT, option); + break; + + case CURL_WANTNO: + switch(tn->usq[option]) { + case CURL_EMPTY: + /* Already negotiating for NO */ + break; + case CURL_OPPOSITE: + tn->usq[option] = CURL_EMPTY; + break; + } + break; + + case CURL_WANTYES: + switch(tn->usq[option]) { + case CURL_EMPTY: + tn->usq[option] = CURL_OPPOSITE; + break; + case CURL_OPPOSITE: + break; + } + break; + } + } +} + +static +void rec_do(struct Curl_easy *data, int option) +{ + struct TELNET *tn = data->req.p.telnet; + switch(tn->us[option]) { + case CURL_NO: + if(tn->us_preferred[option] == CURL_YES) { + tn->us[option] = CURL_YES; + send_negotiation(data, CURL_WILL, option); + if(tn->subnegotiation[option] == CURL_YES) + /* transmission of data option */ + sendsuboption(data, option); + } + else if(tn->subnegotiation[option] == CURL_YES) { + /* send information to achieve this option */ + tn->us[option] = CURL_YES; + send_negotiation(data, CURL_WILL, option); + sendsuboption(data, option); + } + else + send_negotiation(data, CURL_WONT, option); + break; + + case CURL_YES: + /* Already enabled */ + break; + + case CURL_WANTNO: + switch(tn->usq[option]) { + case CURL_EMPTY: + /* Error: DONT answered by WILL */ + tn->us[option] = CURL_NO; + break; + case CURL_OPPOSITE: + /* Error: DONT answered by WILL */ + tn->us[option] = CURL_YES; + tn->usq[option] = CURL_EMPTY; + break; + } + break; + + case CURL_WANTYES: + switch(tn->usq[option]) { + case CURL_EMPTY: + tn->us[option] = CURL_YES; + if(tn->subnegotiation[option] == CURL_YES) { + /* transmission of data option */ + sendsuboption(data, option); + } + break; + case CURL_OPPOSITE: + tn->us[option] = CURL_WANTNO; + tn->himq[option] = CURL_EMPTY; + send_negotiation(data, CURL_WONT, option); + break; + } + break; + } +} + +static +void rec_dont(struct Curl_easy *data, int option) +{ + struct TELNET *tn = data->req.p.telnet; + switch(tn->us[option]) { + case CURL_NO: + /* Already disabled */ + break; + + case CURL_YES: + tn->us[option] = CURL_NO; + send_negotiation(data, CURL_WONT, option); + break; + + case CURL_WANTNO: + switch(tn->usq[option]) { + case CURL_EMPTY: + tn->us[option] = CURL_NO; + break; + + case CURL_OPPOSITE: + tn->us[option] = CURL_WANTYES; + tn->usq[option] = CURL_EMPTY; + send_negotiation(data, CURL_WILL, option); + break; + } + break; + + case CURL_WANTYES: + switch(tn->usq[option]) { + case CURL_EMPTY: + tn->us[option] = CURL_NO; + break; + case CURL_OPPOSITE: + tn->us[option] = CURL_NO; + tn->usq[option] = CURL_EMPTY; + break; + } + break; + } +} + + +static void printsub(struct Curl_easy *data, + int direction, /* '<' or '>' */ + unsigned char *pointer, /* where suboption data is */ + size_t length) /* length of suboption data */ +{ + if(data->set.verbose) { + unsigned int i = 0; + if(direction) { + infof(data, "%s IAC SB ", (direction == '<')? "RCVD":"SENT"); + if(length >= 3) { + int j; + + i = pointer[length-2]; + j = pointer[length-1]; + + if(i != CURL_IAC || j != CURL_SE) { + infof(data, "(terminated by "); + if(CURL_TELOPT_OK(i)) + infof(data, "%s ", CURL_TELOPT(i)); + else if(CURL_TELCMD_OK(i)) + infof(data, "%s ", CURL_TELCMD(i)); + else + infof(data, "%u ", i); + if(CURL_TELOPT_OK(j)) + infof(data, "%s", CURL_TELOPT(j)); + else if(CURL_TELCMD_OK(j)) + infof(data, "%s", CURL_TELCMD(j)); + else + infof(data, "%d", j); + infof(data, ", not IAC SE) "); + } + } + length -= 2; + } + if(length < 1) { + infof(data, "(Empty suboption?)"); + return; + } + + if(CURL_TELOPT_OK(pointer[0])) { + switch(pointer[0]) { + case CURL_TELOPT_TTYPE: + case CURL_TELOPT_XDISPLOC: + case CURL_TELOPT_NEW_ENVIRON: + case CURL_TELOPT_NAWS: + infof(data, "%s", CURL_TELOPT(pointer[0])); + break; + default: + infof(data, "%s (unsupported)", CURL_TELOPT(pointer[0])); + break; + } + } + else + infof(data, "%d (unknown)", pointer[i]); + + switch(pointer[0]) { + case CURL_TELOPT_NAWS: + if(length > 4) + infof(data, "Width: %d ; Height: %d", (pointer[1]<<8) | pointer[2], + (pointer[3]<<8) | pointer[4]); + break; + default: + switch(pointer[1]) { + case CURL_TELQUAL_IS: + infof(data, " IS"); + break; + case CURL_TELQUAL_SEND: + infof(data, " SEND"); + break; + case CURL_TELQUAL_INFO: + infof(data, " INFO/REPLY"); + break; + case CURL_TELQUAL_NAME: + infof(data, " NAME"); + break; + } + + switch(pointer[0]) { + case CURL_TELOPT_TTYPE: + case CURL_TELOPT_XDISPLOC: + pointer[length] = 0; + infof(data, " \"%s\"", &pointer[2]); + break; + case CURL_TELOPT_NEW_ENVIRON: + if(pointer[1] == CURL_TELQUAL_IS) { + infof(data, " "); + for(i = 3; i < length; i++) { + switch(pointer[i]) { + case CURL_NEW_ENV_VAR: + infof(data, ", "); + break; + case CURL_NEW_ENV_VALUE: + infof(data, " = "); + break; + default: + infof(data, "%c", pointer[i]); + break; + } + } + } + break; + default: + for(i = 2; i < length; i++) + infof(data, " %.2x", pointer[i]); + break; + } + } + } +} + +static bool str_is_nonascii(const char *str) +{ + size_t len = strlen(str); + while(len--) { + if(*str & 0x80) + return TRUE; + str++; + } + return FALSE; +} + +static CURLcode check_telnet_options(struct Curl_easy *data) +{ + struct curl_slist *head; + struct curl_slist *beg; + struct TELNET *tn = data->req.p.telnet; + CURLcode result = CURLE_OK; + + /* Add the user name as an environment variable if it + was given on the command line */ + if(data->state.aptr.user) { + char buffer[256]; + if(str_is_nonascii(data->conn->user)) + return CURLE_BAD_FUNCTION_ARGUMENT; + msnprintf(buffer, sizeof(buffer), "USER,%s", data->conn->user); + beg = curl_slist_append(tn->telnet_vars, buffer); + if(!beg) { + curl_slist_free_all(tn->telnet_vars); + tn->telnet_vars = NULL; + return CURLE_OUT_OF_MEMORY; + } + tn->telnet_vars = beg; + tn->us_preferred[CURL_TELOPT_NEW_ENVIRON] = CURL_YES; + } + + for(head = data->set.telnet_options; head && !result; head = head->next) { + size_t olen; + char *option = head->data; + char *arg; + char *sep = strchr(option, '='); + if(sep) { + olen = sep - option; + arg = ++sep; + if(str_is_nonascii(arg)) + continue; + switch(olen) { + case 5: + /* Terminal type */ + if(strncasecompare(option, "TTYPE", 5)) { + strncpy(tn->subopt_ttype, arg, 31); + tn->subopt_ttype[31] = 0; /* String termination */ + tn->us_preferred[CURL_TELOPT_TTYPE] = CURL_YES; + } + else + result = CURLE_UNKNOWN_OPTION; + break; + + case 8: + /* Display variable */ + if(strncasecompare(option, "XDISPLOC", 8)) { + strncpy(tn->subopt_xdisploc, arg, 127); + tn->subopt_xdisploc[127] = 0; /* String termination */ + tn->us_preferred[CURL_TELOPT_XDISPLOC] = CURL_YES; + } + else + result = CURLE_UNKNOWN_OPTION; + break; + + case 7: + /* Environment variable */ + if(strncasecompare(option, "NEW_ENV", 7)) { + beg = curl_slist_append(tn->telnet_vars, arg); + if(!beg) { + result = CURLE_OUT_OF_MEMORY; + break; + } + tn->telnet_vars = beg; + tn->us_preferred[CURL_TELOPT_NEW_ENVIRON] = CURL_YES; + } + else + result = CURLE_UNKNOWN_OPTION; + break; + + case 2: + /* Window Size */ + if(strncasecompare(option, "WS", 2)) { + char *p; + unsigned long x = strtoul(arg, &p, 10); + unsigned long y = 0; + if(x && (x <= 0xffff) && Curl_raw_tolower(*p) == 'x') { + p++; + y = strtoul(p, NULL, 10); + if(y && (y <= 0xffff)) { + tn->subopt_wsx = (unsigned short)x; + tn->subopt_wsy = (unsigned short)y; + tn->us_preferred[CURL_TELOPT_NAWS] = CURL_YES; + } + } + if(!y) { + failf(data, "Syntax error in telnet option: %s", head->data); + result = CURLE_SETOPT_OPTION_SYNTAX; + } + } + else + result = CURLE_UNKNOWN_OPTION; + break; + + case 6: + /* To take care or not of the 8th bit in data exchange */ + if(strncasecompare(option, "BINARY", 6)) { + int binary_option = atoi(arg); + if(binary_option != 1) { + tn->us_preferred[CURL_TELOPT_BINARY] = CURL_NO; + tn->him_preferred[CURL_TELOPT_BINARY] = CURL_NO; + } + } + else + result = CURLE_UNKNOWN_OPTION; + break; + default: + failf(data, "Unknown telnet option %s", head->data); + result = CURLE_UNKNOWN_OPTION; + break; + } + } + else { + failf(data, "Syntax error in telnet option: %s", head->data); + result = CURLE_SETOPT_OPTION_SYNTAX; + } + } + + if(result) { + curl_slist_free_all(tn->telnet_vars); + tn->telnet_vars = NULL; + } + + return result; +} + +/* + * suboption() + * + * Look at the sub-option buffer, and try to be helpful to the other + * side. + */ + +static void suboption(struct Curl_easy *data) +{ + struct curl_slist *v; + unsigned char temp[2048]; + ssize_t bytes_written; + size_t len; + int err; + struct TELNET *tn = data->req.p.telnet; + struct connectdata *conn = data->conn; + + printsub(data, '<', (unsigned char *)tn->subbuffer, CURL_SB_LEN(tn) + 2); + switch(CURL_SB_GET(tn)) { + case CURL_TELOPT_TTYPE: + len = strlen(tn->subopt_ttype) + 4 + 2; + msnprintf((char *)temp, sizeof(temp), + "%c%c%c%c%s%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_TTYPE, + CURL_TELQUAL_IS, tn->subopt_ttype, CURL_IAC, CURL_SE); + bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len); + if(bytes_written < 0) { + err = SOCKERRNO; + failf(data,"Sending data failed (%d)",err); + } + printsub(data, '>', &temp[2], len-2); + break; + case CURL_TELOPT_XDISPLOC: + len = strlen(tn->subopt_xdisploc) + 4 + 2; + msnprintf((char *)temp, sizeof(temp), + "%c%c%c%c%s%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_XDISPLOC, + CURL_TELQUAL_IS, tn->subopt_xdisploc, CURL_IAC, CURL_SE); + bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len); + if(bytes_written < 0) { + err = SOCKERRNO; + failf(data,"Sending data failed (%d)",err); + } + printsub(data, '>', &temp[2], len-2); + break; + case CURL_TELOPT_NEW_ENVIRON: + msnprintf((char *)temp, sizeof(temp), + "%c%c%c%c", CURL_IAC, CURL_SB, CURL_TELOPT_NEW_ENVIRON, + CURL_TELQUAL_IS); + len = 4; + + for(v = tn->telnet_vars; v; v = v->next) { + size_t tmplen = (strlen(v->data) + 1); + /* Add the variable if it fits */ + if(len + tmplen < (int)sizeof(temp)-6) { + char *s = strchr(v->data, ','); + if(!s) + len += msnprintf((char *)&temp[len], sizeof(temp) - len, + "%c%s", CURL_NEW_ENV_VAR, v->data); + else { + size_t vlen = s - v->data; + len += msnprintf((char *)&temp[len], sizeof(temp) - len, + "%c%.*s%c%s", CURL_NEW_ENV_VAR, + (int)vlen, v->data, CURL_NEW_ENV_VALUE, ++s); + } + } + } + msnprintf((char *)&temp[len], sizeof(temp) - len, + "%c%c", CURL_IAC, CURL_SE); + len += 2; + bytes_written = swrite(conn->sock[FIRSTSOCKET], temp, len); + if(bytes_written < 0) { + err = SOCKERRNO; + failf(data,"Sending data failed (%d)",err); + } + printsub(data, '>', &temp[2], len-2); + break; + } + return; +} + + +/* + * sendsuboption() + * + * Send suboption information to the server side. + */ + +static void sendsuboption(struct Curl_easy *data, int option) +{ + ssize_t bytes_written; + int err; + unsigned short x, y; + unsigned char *uc1, *uc2; + struct TELNET *tn = data->req.p.telnet; + struct connectdata *conn = data->conn; + + switch(option) { + case CURL_TELOPT_NAWS: + /* We prepare data to be sent */ + CURL_SB_CLEAR(tn); + CURL_SB_ACCUM(tn, CURL_IAC); + CURL_SB_ACCUM(tn, CURL_SB); + CURL_SB_ACCUM(tn, CURL_TELOPT_NAWS); + /* We must deal either with little or big endian processors */ + /* Window size must be sent according to the 'network order' */ + x = htons(tn->subopt_wsx); + y = htons(tn->subopt_wsy); + uc1 = (unsigned char *)&x; + uc2 = (unsigned char *)&y; + CURL_SB_ACCUM(tn, uc1[0]); + CURL_SB_ACCUM(tn, uc1[1]); + CURL_SB_ACCUM(tn, uc2[0]); + CURL_SB_ACCUM(tn, uc2[1]); + + CURL_SB_ACCUM(tn, CURL_IAC); + CURL_SB_ACCUM(tn, CURL_SE); + CURL_SB_TERM(tn); + /* data suboption is now ready */ + + printsub(data, '>', (unsigned char *)tn->subbuffer + 2, + CURL_SB_LEN(tn)-2); + + /* we send the header of the suboption... */ + bytes_written = swrite(conn->sock[FIRSTSOCKET], tn->subbuffer, 3); + if(bytes_written < 0) { + err = SOCKERRNO; + failf(data, "Sending data failed (%d)", err); + } + /* ... then the window size with the send_telnet_data() function + to deal with 0xFF cases ... */ + send_telnet_data(data, (char *)tn->subbuffer + 3, 4); + /* ... and the footer */ + bytes_written = swrite(conn->sock[FIRSTSOCKET], tn->subbuffer + 7, 2); + if(bytes_written < 0) { + err = SOCKERRNO; + failf(data, "Sending data failed (%d)", err); + } + break; + } +} + + +static +CURLcode telrcv(struct Curl_easy *data, + const unsigned char *inbuf, /* Data received from socket */ + ssize_t count) /* Number of bytes received */ +{ + unsigned char c; + CURLcode result; + int in = 0; + int startwrite = -1; + struct TELNET *tn = data->req.p.telnet; + +#define startskipping() \ + if(startwrite >= 0) { \ + result = Curl_client_write(data, \ + CLIENTWRITE_BODY, \ + (char *)&inbuf[startwrite], \ + in-startwrite); \ + if(result) \ + return result; \ + } \ + startwrite = -1 + +#define writebyte() \ + if(startwrite < 0) \ + startwrite = in + +#define bufferflush() startskipping() + + while(count--) { + c = inbuf[in]; + + switch(tn->telrcv_state) { + case CURL_TS_CR: + tn->telrcv_state = CURL_TS_DATA; + if(c == '\0') { + startskipping(); + break; /* Ignore \0 after CR */ + } + writebyte(); + break; + + case CURL_TS_DATA: + if(c == CURL_IAC) { + tn->telrcv_state = CURL_TS_IAC; + startskipping(); + break; + } + else if(c == '\r') + tn->telrcv_state = CURL_TS_CR; + writebyte(); + break; + + case CURL_TS_IAC: + process_iac: + DEBUGASSERT(startwrite < 0); + switch(c) { + case CURL_WILL: + tn->telrcv_state = CURL_TS_WILL; + break; + case CURL_WONT: + tn->telrcv_state = CURL_TS_WONT; + break; + case CURL_DO: + tn->telrcv_state = CURL_TS_DO; + break; + case CURL_DONT: + tn->telrcv_state = CURL_TS_DONT; + break; + case CURL_SB: + CURL_SB_CLEAR(tn); + tn->telrcv_state = CURL_TS_SB; + break; + case CURL_IAC: + tn->telrcv_state = CURL_TS_DATA; + writebyte(); + break; + case CURL_DM: + case CURL_NOP: + case CURL_GA: + default: + tn->telrcv_state = CURL_TS_DATA; + printoption(data, "RCVD", CURL_IAC, c); + break; + } + break; + + case CURL_TS_WILL: + printoption(data, "RCVD", CURL_WILL, c); + tn->please_negotiate = 1; + rec_will(data, c); + tn->telrcv_state = CURL_TS_DATA; + break; + + case CURL_TS_WONT: + printoption(data, "RCVD", CURL_WONT, c); + tn->please_negotiate = 1; + rec_wont(data, c); + tn->telrcv_state = CURL_TS_DATA; + break; + + case CURL_TS_DO: + printoption(data, "RCVD", CURL_DO, c); + tn->please_negotiate = 1; + rec_do(data, c); + tn->telrcv_state = CURL_TS_DATA; + break; + + case CURL_TS_DONT: + printoption(data, "RCVD", CURL_DONT, c); + tn->please_negotiate = 1; + rec_dont(data, c); + tn->telrcv_state = CURL_TS_DATA; + break; + + case CURL_TS_SB: + if(c == CURL_IAC) + tn->telrcv_state = CURL_TS_SE; + else + CURL_SB_ACCUM(tn, c); + break; + + case CURL_TS_SE: + if(c != CURL_SE) { + if(c != CURL_IAC) { + /* + * This is an error. We only expect to get "IAC IAC" or "IAC SE". + * Several things may have happened. An IAC was not doubled, the + * IAC SE was left off, or another option got inserted into the + * suboption are all possibilities. If we assume that the IAC was + * not doubled, and really the IAC SE was left off, we could get + * into an infinite loop here. So, instead, we terminate the + * suboption, and process the partial suboption if we can. + */ + CURL_SB_ACCUM(tn, CURL_IAC); + CURL_SB_ACCUM(tn, c); + tn->subpointer -= 2; + CURL_SB_TERM(tn); + + printoption(data, "In SUBOPTION processing, RCVD", CURL_IAC, c); + suboption(data); /* handle sub-option */ + tn->telrcv_state = CURL_TS_IAC; + goto process_iac; + } + CURL_SB_ACCUM(tn, c); + tn->telrcv_state = CURL_TS_SB; + } + else { + CURL_SB_ACCUM(tn, CURL_IAC); + CURL_SB_ACCUM(tn, CURL_SE); + tn->subpointer -= 2; + CURL_SB_TERM(tn); + suboption(data); /* handle sub-option */ + tn->telrcv_state = CURL_TS_DATA; + } + break; + } + ++in; + } + bufferflush(); + return CURLE_OK; +} + +/* Escape and send a telnet data block */ +static CURLcode send_telnet_data(struct Curl_easy *data, + char *buffer, ssize_t nread) +{ + ssize_t escapes, i, outlen; + unsigned char *outbuf = NULL; + CURLcode result = CURLE_OK; + ssize_t bytes_written, total_written; + struct connectdata *conn = data->conn; + + /* Determine size of new buffer after escaping */ + escapes = 0; + for(i = 0; i < nread; i++) + if((unsigned char)buffer[i] == CURL_IAC) + escapes++; + outlen = nread + escapes; + + if(outlen == nread) + outbuf = (unsigned char *)buffer; + else { + ssize_t j; + outbuf = malloc(nread + escapes + 1); + if(!outbuf) + return CURLE_OUT_OF_MEMORY; + + j = 0; + for(i = 0; i < nread; i++) { + outbuf[j++] = (unsigned char)buffer[i]; + if((unsigned char)buffer[i] == CURL_IAC) + outbuf[j++] = CURL_IAC; + } + outbuf[j] = '\0'; + } + + total_written = 0; + while(!result && total_written < outlen) { + /* Make sure socket is writable to avoid EWOULDBLOCK condition */ + struct pollfd pfd[1]; + pfd[0].fd = conn->sock[FIRSTSOCKET]; + pfd[0].events = POLLOUT; + switch(Curl_poll(pfd, 1, -1)) { + case -1: /* error, abort writing */ + case 0: /* timeout (will never happen) */ + result = CURLE_SEND_ERROR; + break; + default: /* write! */ + bytes_written = 0; + result = Curl_write(data, conn->sock[FIRSTSOCKET], + outbuf + total_written, + outlen - total_written, + &bytes_written); + total_written += bytes_written; + break; + } + } + + /* Free malloc copy if escaped */ + if(outbuf != (unsigned char *)buffer) + free(outbuf); + + return result; +} + +static CURLcode telnet_done(struct Curl_easy *data, + CURLcode status, bool premature) +{ + struct TELNET *tn = data->req.p.telnet; + (void)status; /* unused */ + (void)premature; /* not used */ + + if(!tn) + return CURLE_OK; + + curl_slist_free_all(tn->telnet_vars); + tn->telnet_vars = NULL; + return CURLE_OK; +} + +static CURLcode telnet_do(struct Curl_easy *data, bool *done) +{ + CURLcode result; + struct connectdata *conn = data->conn; + curl_socket_t sockfd = conn->sock[FIRSTSOCKET]; +#ifdef USE_WINSOCK + WSAEVENT event_handle; + WSANETWORKEVENTS events; + HANDLE stdin_handle; + HANDLE objs[2]; + DWORD obj_count; + DWORD wait_timeout; + DWORD readfile_read; + int err; +#else + timediff_t interval_ms; + struct pollfd pfd[2]; + int poll_cnt; + curl_off_t total_dl = 0; + curl_off_t total_ul = 0; +#endif + ssize_t nread; + struct curltime now; + bool keepon = TRUE; + char *buf = data->state.buffer; + struct TELNET *tn; + + *done = TRUE; /* unconditionally */ + + result = init_telnet(data); + if(result) + return result; + + tn = data->req.p.telnet; + + result = check_telnet_options(data); + if(result) + return result; + +#ifdef USE_WINSOCK + /* We want to wait for both stdin and the socket. Since + ** the select() function in winsock only works on sockets + ** we have to use the WaitForMultipleObjects() call. + */ + + /* First, create a sockets event object */ + event_handle = WSACreateEvent(); + if(event_handle == WSA_INVALID_EVENT) { + failf(data, "WSACreateEvent failed (%d)", SOCKERRNO); + return CURLE_FAILED_INIT; + } + + /* Tell winsock what events we want to listen to */ + if(WSAEventSelect(sockfd, event_handle, FD_READ|FD_CLOSE) == SOCKET_ERROR) { + WSACloseEvent(event_handle); + return CURLE_OK; + } + + /* The get the Windows file handle for stdin */ + stdin_handle = GetStdHandle(STD_INPUT_HANDLE); + + /* Create the list of objects to wait for */ + objs[0] = event_handle; + objs[1] = stdin_handle; + + /* If stdin_handle is a pipe, use PeekNamedPipe() method to check it, + else use the old WaitForMultipleObjects() way */ + if(GetFileType(stdin_handle) == FILE_TYPE_PIPE || + data->set.is_fread_set) { + /* Don't wait for stdin_handle, just wait for event_handle */ + obj_count = 1; + /* Check stdin_handle per 100 milliseconds */ + wait_timeout = 100; + } + else { + obj_count = 2; + wait_timeout = 1000; + } + + /* Keep on listening and act on events */ + while(keepon) { + const DWORD buf_size = (DWORD)data->set.buffer_size; + DWORD waitret = WaitForMultipleObjects(obj_count, objs, + FALSE, wait_timeout); + switch(waitret) { + + case WAIT_TIMEOUT: + { + for(;;) { + if(data->set.is_fread_set) { + size_t n; + /* read from user-supplied method */ + n = data->state.fread_func(buf, 1, buf_size, data->state.in); + if(n == CURL_READFUNC_ABORT) { + keepon = FALSE; + result = CURLE_READ_ERROR; + break; + } + + if(n == CURL_READFUNC_PAUSE) + break; + + if(n == 0) /* no bytes */ + break; + + /* fall through with number of bytes read */ + readfile_read = (DWORD)n; + } + else { + /* read from stdin */ + if(!PeekNamedPipe(stdin_handle, NULL, 0, NULL, + &readfile_read, NULL)) { + keepon = FALSE; + result = CURLE_READ_ERROR; + break; + } + + if(!readfile_read) + break; + + if(!ReadFile(stdin_handle, buf, buf_size, + &readfile_read, NULL)) { + keepon = FALSE; + result = CURLE_READ_ERROR; + break; + } + } + + result = send_telnet_data(data, buf, readfile_read); + if(result) { + keepon = FALSE; + break; + } + } + } + break; + + case WAIT_OBJECT_0 + 1: + { + if(!ReadFile(stdin_handle, buf, buf_size, + &readfile_read, NULL)) { + keepon = FALSE; + result = CURLE_READ_ERROR; + break; + } + + result = send_telnet_data(data, buf, readfile_read); + if(result) { + keepon = FALSE; + break; + } + } + break; + + case WAIT_OBJECT_0: + { + events.lNetworkEvents = 0; + if(WSAEnumNetworkEvents(sockfd, event_handle, &events) == SOCKET_ERROR) { + err = SOCKERRNO; + if(err != EINPROGRESS) { + infof(data, "WSAEnumNetworkEvents failed (%d)", err); + keepon = FALSE; + result = CURLE_READ_ERROR; + } + break; + } + if(events.lNetworkEvents & FD_READ) { + /* read data from network */ + result = Curl_read(data, sockfd, buf, data->set.buffer_size, &nread); + /* read would've blocked. Loop again */ + if(result == CURLE_AGAIN) + break; + /* returned not-zero, this an error */ + else if(result) { + keepon = FALSE; + break; + } + /* returned zero but actually received 0 or less here, + the server closed the connection and we bail out */ + else if(nread <= 0) { + keepon = FALSE; + break; + } + + result = telrcv(data, (unsigned char *) buf, nread); + if(result) { + keepon = FALSE; + break; + } + + /* Negotiate if the peer has started negotiating, + otherwise don't. We don't want to speak telnet with + non-telnet servers, like POP or SMTP. */ + if(tn->please_negotiate && !tn->already_negotiated) { + negotiate(data); + tn->already_negotiated = 1; + } + } + if(events.lNetworkEvents & FD_CLOSE) { + keepon = FALSE; + } + } + break; + + } + + if(data->set.timeout) { + now = Curl_now(); + if(Curl_timediff(now, conn->created) >= data->set.timeout) { + failf(data, "Time-out"); + result = CURLE_OPERATION_TIMEDOUT; + keepon = FALSE; + } + } + } + + /* We called WSACreateEvent, so call WSACloseEvent */ + if(!WSACloseEvent(event_handle)) { + infof(data, "WSACloseEvent failed (%d)", SOCKERRNO); + } +#else + pfd[0].fd = sockfd; + pfd[0].events = POLLIN; + + if(data->set.is_fread_set) { + poll_cnt = 1; + interval_ms = 100; /* poll user-supplied read function */ + } + else { + /* really using fread, so infile is a FILE* */ + pfd[1].fd = fileno((FILE *)data->state.in); + pfd[1].events = POLLIN; + poll_cnt = 2; + interval_ms = 1 * 1000; + } + + while(keepon) { + DEBUGF(infof(data, "telnet_do(handle=%p), poll %d fds", data, poll_cnt)); + switch(Curl_poll(pfd, poll_cnt, interval_ms)) { + case -1: /* error, stop reading */ + keepon = FALSE; + continue; + case 0: /* timeout */ + pfd[0].revents = 0; + pfd[1].revents = 0; + /* FALLTHROUGH */ + default: /* read! */ + if(pfd[0].revents & POLLIN) { + /* read data from network */ + result = Curl_read(data, sockfd, buf, data->set.buffer_size, &nread); + /* read would've blocked. Loop again */ + if(result == CURLE_AGAIN) + break; + /* returned not-zero, this an error */ + if(result) { + keepon = FALSE; + /* TODO: in test 1452, macOS sees a ECONNRESET sometimes? + * Is this the telnet test server not shutting down the socket + * in a clean way? Seems to be timing related, happens more + * on slow debug build */ + if(data->state.os_errno == ECONNRESET) { + DEBUGF(infof(data, "telnet_do(handle=%p), unexpected ECONNRESET" + " on recv", data)); + } + break; + } + /* returned zero but actually received 0 or less here, + the server closed the connection and we bail out */ + else if(nread <= 0) { + keepon = FALSE; + break; + } + + total_dl += nread; + Curl_pgrsSetDownloadCounter(data, total_dl); + result = telrcv(data, (unsigned char *)buf, nread); + if(result) { + keepon = FALSE; + break; + } + + /* Negotiate if the peer has started negotiating, + otherwise don't. We don't want to speak telnet with + non-telnet servers, like POP or SMTP. */ + if(tn->please_negotiate && !tn->already_negotiated) { + negotiate(data); + tn->already_negotiated = 1; + } + } + + nread = 0; + if(poll_cnt == 2) { + if(pfd[1].revents & POLLIN) { /* read from in file */ + nread = read(pfd[1].fd, buf, data->set.buffer_size); + } + } + else { + /* read from user-supplied method */ + nread = (int)data->state.fread_func(buf, 1, data->set.buffer_size, + data->state.in); + if(nread == CURL_READFUNC_ABORT) { + keepon = FALSE; + break; + } + if(nread == CURL_READFUNC_PAUSE) + break; + } + + if(nread > 0) { + result = send_telnet_data(data, buf, nread); + if(result) { + keepon = FALSE; + break; + } + total_ul += nread; + Curl_pgrsSetUploadCounter(data, total_ul); + } + else if(nread < 0) + keepon = FALSE; + + break; + } /* poll switch statement */ + + if(data->set.timeout) { + now = Curl_now(); + if(Curl_timediff(now, conn->created) >= data->set.timeout) { + failf(data, "Time-out"); + result = CURLE_OPERATION_TIMEDOUT; + keepon = FALSE; + } + } + + if(Curl_pgrsUpdate(data)) { + result = CURLE_ABORTED_BY_CALLBACK; + break; + } + } +#endif + /* mark this as "no further transfer wanted" */ + Curl_setup_transfer(data, -1, -1, FALSE, -1); + + return result; +} +#endif |