From 1934c297871ddb9affc8361b6c7d51546d0163d5 Mon Sep 17 00:00:00 2001 Date: Tue, 22 Nov 2011 23:16:23 +0100 Subject: [PATCH] This patch: 1) enables the Window Size option 2) allows the server to enable the echo mode 3) allows an app using libcurl to disable the default binary mode Signed-off-by: Laurent Rabret --- lib/arpa_telnet.h | 3 + lib/telnet.c | 239 ++++++++++++++++++++++++++++++++++++++++++----------- 2 files changed, 195 insertions(+), 47 deletions(-) diff --git a/lib/arpa_telnet.h b/lib/arpa_telnet.h index 6626928..7b7ac84 100644 --- a/lib/arpa_telnet.h +++ b/lib/arpa_telnet.h @@ -26,11 +26,14 @@ * Telnet option defines. Add more here if in need. */ #define CURL_TELOPT_BINARY 0 /* binary 8bit data */ +#define CURL_TELOPT_ECHO 1 /* just echo! */ #define CURL_TELOPT_SGA 3 /* Suppress Go Ahead */ #define CURL_TELOPT_EXOPL 255 /* EXtended OPtions List */ #define CURL_TELOPT_TTYPE 24 /* Terminal TYPE */ +#define CURL_TELOPT_NAWS 31 /* Negotiate About Window Size */ #define CURL_TELOPT_XDISPLOC 35 /* X DISPlay LOCation */ + #define CURL_TELOPT_NEW_ENVIRON 39 /* NEW ENVIRONment variables */ #define CURL_NEW_ENV_VAR 0 #define CURL_NEW_ENV_VALUE 1 diff --git a/lib/telnet.c b/lib/telnet.c index 59094b6..f0c083b 100644 --- a/lib/telnet.c +++ b/lib/telnet.c @@ -116,10 +116,13 @@ static void printsub(struct SessionHandle *data, int direction, unsigned char *pointer, size_t length); static void suboption(struct connectdata *); +static void sendsuboption(struct connectdata *conn, int option); static CURLcode telnet_do(struct connectdata *conn, bool *done); static CURLcode telnet_done(struct connectdata *conn, CURLcode, bool premature); +static CURLcode send_telnet_data(struct connectdata *conn, + char *buffer, ssize_t nread); /* For negotiation compliant to RFC 1143 */ #define CURL_NO 0 @@ -155,8 +158,11 @@ struct TELNET { 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 */ struct curl_slist *telnet_vars; /* Environment variables */ /* suboptions */ @@ -249,11 +255,37 @@ CURLcode init_telnet(struct connectdata *conn) CURL_SB_CLEAR(tn); /* Set the options we want by default */ - tn->us_preferred[CURL_TELOPT_BINARY] = CURL_YES; tn->us_preferred[CURL_TELOPT_SGA] = CURL_YES; - tn->him_preferred[CURL_TELOPT_BINARY] = 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 behaviour + 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; } @@ -263,6 +295,8 @@ static void negotiate(struct connectdata *conn) struct TELNET *tn = (struct TELNET *) conn->data->state.proto.telnet; for(i = 0;i < CURL_NTELOPTS;i++) { + if(i==CURL_TELOPT_ECHO ) continue; + if(tn->us_preferred[i] == CURL_YES) set_local_option(conn, i, CURL_YES); @@ -575,7 +609,17 @@ void rec_do(struct connectdata *conn, int option) if(tn->us_preferred[option] == CURL_YES) { tn->us[option] = CURL_YES; send_negotiation(conn, CURL_WILL, option); + if(tn->subnegotiation[option] == CURL_YES) { + /* transmission of data option */ + sendsuboption(conn, option); + } } + else if (tn->subnegotiation[option] == CURL_YES) { + /* send information to achieve this option*/ + tn->us[option] = CURL_YES; + send_negotiation(conn, CURL_WILL, option); + sendsuboption(conn, option); + } else send_negotiation(conn, CURL_WONT, option); break; @@ -602,6 +646,10 @@ void rec_do(struct connectdata *conn, int option) switch(tn->usq[option]) { case CURL_EMPTY: tn->us[option] = CURL_YES; + if (tn->subnegotiation[option] == CURL_YES) { + /* transmission of data option */ + sendsuboption(conn, option); + } break; case CURL_OPPOSITE: tn->us[option] = CURL_WANTNO; @@ -662,6 +710,7 @@ static void printsub(struct SessionHandle *data, size_t length) /* length of suboption data */ { unsigned int i = 0; + unsigned short * pval; if(data->set.verbose) { if(direction) { @@ -701,6 +750,7 @@ static void printsub(struct SessionHandle *data, 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: @@ -711,51 +761,57 @@ static void printsub(struct SessionHandle *data, else infof(data, "%d (unknown)", pointer[i]); - 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; - } - + switch(pointer[0]){ + case CURL_TELOPT_NAWS: + pval = (unsigned short*)(pointer+1); + infof(data, "Width: %hu ; Height: %hu", ntohs(pval[0]), ntohs(pval[1])); + 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; + } + } if(direction) infof(data, "\n"); } @@ -770,6 +826,7 @@ static CURLcode check_telnet_options(struct connectdata *conn) struct SessionHandle *data = conn->data; struct TELNET *tn = (struct TELNET *)conn->data->state.proto.telnet; CURLcode result = CURLE_OK; + int binary_option; /* Add the user name as an environment variable if it was given on the command line */ @@ -817,6 +874,31 @@ static CURLcode check_telnet_options(struct connectdata *conn) continue; } + /* Window Size */ + if(Curl_raw_equal(option_keyword, "WS")) { + if(sscanf(option_arg, "%hu%*[xX]%hu", + &tn->subopt_wsx, &tn->subopt_wsy) == 2) { + tn->us_preferred[CURL_TELOPT_NAWS] = CURL_YES; + } + else { + failf(data, "Syntax error in telnet option: %s", head->data); + result = CURLE_TELNET_OPTION_SYNTAX; + break; + } + continue; + } + + /* To take care or not of the 8th bit in data exchange */ + if(Curl_raw_equal(option_keyword, "BINARY")) { + binary_option=atoi(option_arg); + if(binary_option!=1) { + tn->us_preferred[CURL_TELOPT_BINARY] = CURL_NO; + tn->him_preferred[CURL_TELOPT_BINARY] = CURL_NO; + } + continue; + } + + failf(data, "Unknown telnet option %s", head->data); result = CURLE_UNKNOWN_TELNET_OPTION; break; @@ -913,6 +995,69 @@ static void suboption(struct connectdata *conn) return; } + +/* + * sendsuboption() + * + * Send suboption information to the server side. + */ + +static void sendsuboption(struct connectdata *conn, int option) +{ + ssize_t bytes_written; + int err; + unsigned short x, y; + unsigned char*uc1, *uc2; + + struct SessionHandle *data = conn->data; + struct TELNET *tn = (struct TELNET *)data->state.proto.telnet; + + 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 litte or big endien 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(conn, 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; + } + return; +} + + static CURLcode telrcv(struct connectdata *conn, const unsigned char *inbuf, /* Data received from socket */ -- 1.7.7.1.msysgit.0