From 5e4a475d63333a4d61cbce0b0a21bf01cf945f74 Mon Sep 17 00:00:00 2001 From: simon Date: Sun, 10 Jul 2011 14:22:32 +0000 Subject: [PATCH] Add a directory 'contrib/cygtermd', containing the source code for my hacky helper program to let PuTTY act as a local pterm-oid on Cygwin-enabled Windows systems. git-svn-id: svn://svn.tartarus.org/sgt/putty@9191 cda61777-01e9-0310-a592-d414129be87e --- contrib/cygtermd/Makefile | 2 + contrib/cygtermd/README | 11 + contrib/cygtermd/main.c | 174 ++++++++++++++ contrib/cygtermd/malloc.c | 43 ++++ contrib/cygtermd/malloc.h | 56 +++++ contrib/cygtermd/pty.c | 188 +++++++++++++++ contrib/cygtermd/pty.h | 28 +++ contrib/cygtermd/sel.c | 386 +++++++++++++++++++++++++++++++ contrib/cygtermd/sel.h | 161 +++++++++++++ contrib/cygtermd/telnet.c | 570 ++++++++++++++++++++++++++++++++++++++++++++++ contrib/cygtermd/telnet.h | 41 ++++ 11 files changed, 1660 insertions(+) create mode 100644 contrib/cygtermd/Makefile create mode 100644 contrib/cygtermd/README create mode 100644 contrib/cygtermd/main.c create mode 100644 contrib/cygtermd/malloc.c create mode 100644 contrib/cygtermd/malloc.h create mode 100644 contrib/cygtermd/pty.c create mode 100644 contrib/cygtermd/pty.h create mode 100644 contrib/cygtermd/sel.c create mode 100644 contrib/cygtermd/sel.h create mode 100644 contrib/cygtermd/telnet.c create mode 100644 contrib/cygtermd/telnet.h diff --git a/contrib/cygtermd/Makefile b/contrib/cygtermd/Makefile new file mode 100644 index 00000000..831bbcdf --- /dev/null +++ b/contrib/cygtermd/Makefile @@ -0,0 +1,2 @@ +cygtermd.exe: main.c sel.c telnet.c pty.c malloc.c + gcc -o cygtermd.exe main.c sel.c telnet.c pty.c malloc.c diff --git a/contrib/cygtermd/README b/contrib/cygtermd/README new file mode 100644 index 00000000..ebfdfdd7 --- /dev/null +++ b/contrib/cygtermd/README @@ -0,0 +1,11 @@ +This directory contains 'cygtermd', a small and specialist Telnet +server designed to act as middleware between PuTTY and a Cygwin shell +session running on the same machine, so that PuTTY can act as an +xterm-alike for Cygwin. + +To install it, you must compile it from source using Cygwin gcc, +install it in Cygwin's /bin, and configure PuTTY to use it as a local +proxy process. For detailed instructions, see the PuTTY Wishlist page +at + +http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/cygwin-terminal-window.html diff --git a/contrib/cygtermd/main.c b/contrib/cygtermd/main.c new file mode 100644 index 00000000..acf35dd9 --- /dev/null +++ b/contrib/cygtermd/main.c @@ -0,0 +1,174 @@ +/* + * Main program. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include "sel.h" +#include "pty.h" +#include "telnet.h" + +int signalpipe[2]; + +sel *asel; +sel_rfd *netr, *ptyr, *sigr; +int ptyfd; +sel_wfd *netw, *ptyw; +Telnet telnet; + +#define BUF 65536 + +void sigchld(int signum) +{ + write(signalpipe[1], "C", 1); +} + +void fatal(const char *fmt, ...) +{ + va_list ap; + fprintf(stderr, "FIXME: "); + va_start(ap, fmt); + vfprintf(stderr, fmt, ap); + va_end(ap); + fprintf(stderr, "\n"); + exit(1); +} + +void net_readdata(sel_rfd *rfd, void *data, size_t len) +{ + if (len == 0) + exit(0); /* EOF on network - client went away */ + telnet_from_net(telnet, data, len); + if (sel_write(netw, NULL, 0) > BUF) + sel_rfd_freeze(ptyr); + if (sel_write(ptyw, NULL, 0) > BUF) + sel_rfd_freeze(netr); +} + +void net_readerr(sel_rfd *rfd, int error) +{ + fprintf(stderr, "standard input: read: %s\n", strerror(errno)); + exit(1); +} + +void net_written(sel_wfd *wfd, size_t bufsize) +{ + if (bufsize < BUF) + sel_rfd_unfreeze(ptyr); +} + +void net_writeerr(sel_wfd *wfd, int error) +{ + fprintf(stderr, "standard input: write: %s\n", strerror(errno)); + exit(1); +} + +void pty_readdata(sel_rfd *rfd, void *data, size_t len) +{ + if (len == 0) + exit(0); /* EOF on pty */ + telnet_from_pty(telnet, data, len); + if (sel_write(netw, NULL, 0) > BUF) + sel_rfd_freeze(ptyr); + if (sel_write(ptyw, NULL, 0) > BUF) + sel_rfd_freeze(netr); +} + +void pty_readerr(sel_rfd *rfd, int error) +{ + if (error == EIO) /* means EOF, on a pty */ + exit(0); + fprintf(stderr, "pty: read: %s\n", strerror(errno)); + exit(1); +} + +void pty_written(sel_wfd *wfd, size_t bufsize) +{ + if (bufsize < BUF) + sel_rfd_unfreeze(netr); +} + +void pty_writeerr(sel_wfd *wfd, int error) +{ + fprintf(stderr, "pty: write: %s\n", strerror(errno)); + exit(1); +} + +void sig_readdata(sel_rfd *rfd, void *data, size_t len) +{ + char *p = data; + + while (len > 0) { + if (*p == 'C') { + int status; + pid_t pid = waitpid(-1, &status, WNOHANG); + if (WIFEXITED(status) || WIFSIGNALED(status)) + exit(0); /* child process vanished */ + } + } +} + +void sig_readerr(sel_rfd *rfd, int error) +{ + fprintf(stderr, "signal pipe: read: %s\n", strerror(errno)); + exit(1); +} + +int main(int argc, char **argv) +{ + int ret; + int shell_started = 0; + char *directory = NULL; + char **program_args = NULL; + + if (argc > 1 && argv[1][0]) { + directory = argv[1]; + argc--, argv++; + } + if (argc > 1) { + program_args = argv + 1; + } + + pty_preinit(); + + asel = sel_new(NULL); + netr = sel_rfd_add(asel, 0, net_readdata, net_readerr, NULL); + netw = sel_wfd_add(asel, 1, net_written, net_writeerr, NULL); + ptyr = sel_rfd_add(asel, -1, pty_readdata, pty_readerr, NULL); + ptyw = sel_wfd_add(asel, -1, pty_written, pty_writeerr, NULL); + + telnet = telnet_new(netw, ptyw); + + if (pipe(signalpipe) < 0) { + perror("pipe"); + return 1; + } + sigr = sel_rfd_add(asel, signalpipe[0], sig_readdata, + sig_readerr, NULL); + + signal(SIGCHLD, sigchld); + + do { + struct shell_data shdata; + + ret = sel_iterate(asel, -1); + if (!shell_started && telnet_shell_ok(telnet, &shdata)) { + ptyfd = run_program_in_pty(&shdata, directory, program_args); + sel_rfd_setfd(ptyr, ptyfd); + sel_wfd_setfd(ptyw, ptyfd); + shell_started = 1; + } + } while (ret == 0); + + return 0; +} diff --git a/contrib/cygtermd/malloc.c b/contrib/cygtermd/malloc.c new file mode 100644 index 00000000..5c5b94eb --- /dev/null +++ b/contrib/cygtermd/malloc.c @@ -0,0 +1,43 @@ +/* + * malloc.c: implementation of malloc.h + */ + +#include +#include + +#include "malloc.h" + +extern void fatal(const char *, ...); + +void *smalloc(size_t size) { + void *p; + p = malloc(size); + if (!p) { + fatal("out of memory"); + } + return p; +} + +void sfree(void *p) { + if (p) { + free(p); + } +} + +void *srealloc(void *p, size_t size) { + void *q; + if (p) { + q = realloc(p, size); + } else { + q = malloc(size); + } + if (!q) + fatal("out of memory"); + return q; +} + +char *dupstr(const char *s) { + char *r = smalloc(1+strlen(s)); + strcpy(r,s); + return r; +} diff --git a/contrib/cygtermd/malloc.h b/contrib/cygtermd/malloc.h new file mode 100644 index 00000000..8cd4b30a --- /dev/null +++ b/contrib/cygtermd/malloc.h @@ -0,0 +1,56 @@ +/* + * malloc.h: safe wrappers around malloc, realloc, free, strdup + */ + +#ifndef UMLWRAP_MALLOC_H +#define UMLWRAP_MALLOC_H + +#include + +/* + * smalloc should guarantee to return a useful pointer - Halibut + * can do nothing except die when it's out of memory anyway. + */ +void *smalloc(size_t size); + +/* + * srealloc should guaranteeably be able to realloc NULL + */ +void *srealloc(void *p, size_t size); + +/* + * sfree should guaranteeably deal gracefully with freeing NULL + */ +void sfree(void *p); + +/* + * dupstr is like strdup, but with the never-return-NULL property + * of smalloc (and also reliably defined in all environments :-) + */ +char *dupstr(const char *s); + +/* + * snew allocates one instance of a given type, and casts the + * result so as to type-check that you're assigning it to the + * right kind of pointer. Protects against allocation bugs + * involving allocating the wrong size of thing. + */ +#define snew(type) \ + ( (type *) smalloc (sizeof (type)) ) + +/* + * snewn allocates n instances of a given type, for arrays. + */ +#define snewn(number, type) \ + ( (type *) smalloc ((number) * sizeof (type)) ) + +/* + * sresize wraps realloc so that you specify the new number of + * elements and the type of the element, with the same type- + * checking advantages. Also type-checks the input pointer. + */ +#define sresize(array, number, type) \ + ( (void)sizeof((array)-(type *)0), \ + (type *) srealloc ((array), (number) * sizeof (type)) ) + +#endif /* UMLWRAP_MALLOC_H */ diff --git a/contrib/cygtermd/pty.c b/contrib/cygtermd/pty.c new file mode 100644 index 00000000..e30f9e0e --- /dev/null +++ b/contrib/cygtermd/pty.c @@ -0,0 +1,188 @@ +/* + * pty.c - pseudo-terminal handling + */ + +#define _XOPEN_SOURCE +#include + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "pty.h" +#include "malloc.h" + +static char ptyname[FILENAME_MAX]; +int master = -1; + +void pty_preinit(void) +{ + /* + * Allocate the pty. + */ + master = open("/dev/ptmx", O_RDWR); + if (master < 0) { + perror("/dev/ptmx: open"); + exit(1); + } + + if (grantpt(master) < 0) { + perror("grantpt"); + exit(1); + } + + if (unlockpt(master) < 0) { + perror("unlockpt"); + exit(1); + } +} + +void pty_resize(int w, int h) +{ + struct winsize sz; + + assert(master >= 0); + + sz.ws_row = h; + sz.ws_col = w; + sz.ws_xpixel = sz.ws_ypixel = 0; + ioctl(master, TIOCSWINSZ, &sz); +} + +int run_program_in_pty(const struct shell_data *shdata, + char *directory, char **program_args) +{ + int slave, pid; + char *fallback_args[2]; + + assert(master >= 0); + + ptyname[FILENAME_MAX-1] = '\0'; + strncpy(ptyname, ptsname(master), FILENAME_MAX-1); + +#if 0 + { + struct winsize ws; + struct termios ts; + + /* + * FIXME: think up some good defaults here + */ + + if (!ioctl(0, TIOCGWINSZ, &ws)) + ioctl(master, TIOCSWINSZ, &ws); + if (!tcgetattr(0, &ts)) + tcsetattr(master, TCSANOW, &ts); + } +#endif + + slave = open(ptyname, O_RDWR | O_NOCTTY); + if (slave < 0) { + perror("slave pty: open"); + return 1; + } + + /* + * Fork and execute the command. + */ + pid = fork(); + if (pid < 0) { + perror("fork"); + return 1; + } + + if (pid == 0) { + int i, fd; + + /* + * We are the child. + */ + close(master); + + fcntl(slave, F_SETFD, 0); /* don't close on exec */ + dup2(slave, 0); + dup2(slave, 1); + if (slave != 0 && slave != 1) + close(slave); + dup2(1, 2); + setsid(); + setpgrp(); + i = 0; +#ifdef TIOCNOTTY + if ((fd = open("/dev/tty", O_RDWR)) >= 0) { + ioctl(fd, TIOCNOTTY, &i); + close(fd); + } +#endif +#ifdef TIOCSCTTY + ioctl(0, TIOCSCTTY, &i); +#endif + tcsetpgrp(0, getpgrp()); + + for (i = 0; i < shdata->nenvvars; i++) + putenv(shdata->envvars[i]); + if (shdata->termtype) + putenv(shdata->termtype); + + if (directory) + chdir(directory); + + /* + * Use the provided shell program name, if the user gave + * one. Failing that, use $SHELL; failing that, look up + * the user's default shell in the password file; failing + * _that_, revert to the bog-standard /bin/sh. + */ + if (!program_args) { + char *shell; + + shell = getenv("SHELL"); + if (!shell) { + const char *login; + uid_t uid; + struct passwd *pwd; + + /* + * For maximum generality in the face of multiple + * /etc/passwd entries with different login names and + * shells but a shared uid, we start by using + * getpwnam(getlogin()) if it's available - but we + * insist that its uid must match our real one, or we + * give up and fall back to getpwuid(getuid()). + */ + uid = getuid(); + login = getlogin(); + if (login && (pwd = getpwnam(login)) && pwd->pw_uid == uid) + shell = pwd->pw_shell; + else if ((pwd = getpwuid(uid))) + shell = pwd->pw_shell; + } + if (!shell) + shell = "/bin/sh"; + + fallback_args[0] = shell; + fallback_args[1] = NULL; + program_args = fallback_args; + } + + execv(program_args[0], program_args); + + /* + * If we're here, exec has gone badly foom. + */ + perror("exec"); + exit(127); + } + + close(slave); + + return master; +} diff --git a/contrib/cygtermd/pty.h b/contrib/cygtermd/pty.h new file mode 100644 index 00000000..bee10e47 --- /dev/null +++ b/contrib/cygtermd/pty.h @@ -0,0 +1,28 @@ +/* + * pty.h - FIXME + */ + +#ifndef FIXME_PTY_H +#define FIXME_PTY_H + +#include "telnet.h" /* for struct shdata */ + +/* + * Called at program startup to actually allocate a pty, so that + * we can start passing in resize events as soon as they arrive. + */ +void pty_preinit(void); + +/* + * Set the terminal size for the pty. + */ +void pty_resize(int w, int h); + +/* + * Start a program in a subprocess running in the pty we allocated. + * Returns the fd of the pty master. + */ +int run_program_in_pty(const struct shell_data *shdata, + char *directory, char **program_args); + +#endif /* FIXME_PTY_H */ diff --git a/contrib/cygtermd/sel.c b/contrib/cygtermd/sel.c new file mode 100644 index 00000000..43ec4760 --- /dev/null +++ b/contrib/cygtermd/sel.c @@ -0,0 +1,386 @@ +/* + * sel.c: implementation of sel.h. + */ + +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#include "sel.h" +#include "malloc.h" + +/* ---------------------------------------------------------------------- + * Chunk of code lifted from PuTTY's misc.c to manage buffers of + * data to be written to an fd. + */ + +#define BUFFER_GRANULE 512 + +typedef struct bufchain_tag { + struct bufchain_granule *head, *tail; + size_t buffersize; /* current amount of buffered data */ +} bufchain; +struct bufchain_granule { + struct bufchain_granule *next; + size_t buflen, bufpos; + char buf[BUFFER_GRANULE]; +}; + +static void bufchain_init(bufchain *ch) +{ + ch->head = ch->tail = NULL; + ch->buffersize = 0; +} + +static void bufchain_clear(bufchain *ch) +{ + struct bufchain_granule *b; + while (ch->head) { + b = ch->head; + ch->head = ch->head->next; + sfree(b); + } + ch->tail = NULL; + ch->buffersize = 0; +} + +static size_t bufchain_size(bufchain *ch) +{ + return ch->buffersize; +} + +static void bufchain_add(bufchain *ch, const void *data, size_t len) +{ + const char *buf = (const char *)data; + + if (len == 0) return; + + ch->buffersize += len; + + if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) { + size_t copylen = BUFFER_GRANULE - ch->tail->buflen; + if (copylen > len) + copylen = len; + memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen); + buf += copylen; + len -= copylen; + ch->tail->buflen += copylen; + } + while (len > 0) { + struct bufchain_granule *newbuf; + size_t grainlen = BUFFER_GRANULE; + if (grainlen > len) + grainlen = len; + newbuf = snew(struct bufchain_granule); + newbuf->bufpos = 0; + newbuf->buflen = grainlen; + memcpy(newbuf->buf, buf, grainlen); + buf += grainlen; + len -= grainlen; + if (ch->tail) + ch->tail->next = newbuf; + else + ch->head = ch->tail = newbuf; + newbuf->next = NULL; + ch->tail = newbuf; + } +} + +static void bufchain_consume(bufchain *ch, size_t len) +{ + struct bufchain_granule *tmp; + + assert(ch->buffersize >= len); + while (len > 0) { + size_t remlen = len; + assert(ch->head != NULL); + if (remlen >= ch->head->buflen - ch->head->bufpos) { + remlen = ch->head->buflen - ch->head->bufpos; + tmp = ch->head; + ch->head = tmp->next; + sfree(tmp); + if (!ch->head) + ch->tail = NULL; + } else + ch->head->bufpos += remlen; + ch->buffersize -= remlen; + len -= remlen; + } +} + +static void bufchain_prefix(bufchain *ch, void **data, size_t *len) +{ + *len = ch->head->buflen - ch->head->bufpos; + *data = ch->head->buf + ch->head->bufpos; +} + +/* ---------------------------------------------------------------------- + * The actual implementation of the sel interface. + */ + +struct sel { + void *ctx; + sel_rfd *rhead, *rtail; + sel_wfd *whead, *wtail; +}; + +struct sel_rfd { + sel *parent; + sel_rfd *prev, *next; + sel_readdata_fn_t readdata; + sel_readerr_fn_t readerr; + void *ctx; + int fd; + int frozen; +}; + +struct sel_wfd { + sel *parent; + sel_wfd *prev, *next; + sel_written_fn_t written; + sel_writeerr_fn_t writeerr; + void *ctx; + int fd; + bufchain buf; +}; + +sel *sel_new(void *ctx) +{ + sel *sel = snew(struct sel); + + sel->ctx = ctx; + sel->rhead = sel->rtail = NULL; + sel->whead = sel->wtail = NULL; + + return sel; +} + +sel_wfd *sel_wfd_add(sel *sel, int fd, + sel_written_fn_t written, sel_writeerr_fn_t writeerr, + void *ctx) +{ + sel_wfd *wfd = snew(sel_wfd); + + wfd->written = written; + wfd->writeerr = writeerr; + wfd->ctx = ctx; + wfd->fd = fd; + bufchain_init(&wfd->buf); + + wfd->next = NULL; + wfd->prev = sel->wtail; + if (sel->wtail) + sel->wtail->next = wfd; + else + sel->whead = wfd; + sel->wtail = wfd; + wfd->parent = sel; + + return wfd; +} + +sel_rfd *sel_rfd_add(sel *sel, int fd, + sel_readdata_fn_t readdata, sel_readerr_fn_t readerr, + void *ctx) +{ + sel_rfd *rfd = snew(sel_rfd); + + rfd->readdata = readdata; + rfd->readerr = readerr; + rfd->ctx = ctx; + rfd->fd = fd; + rfd->frozen = 0; + + rfd->next = NULL; + rfd->prev = sel->rtail; + if (sel->rtail) + sel->rtail->next = rfd; + else + sel->rhead = rfd; + sel->rtail = rfd; + rfd->parent = sel; + + return rfd; +} + +size_t sel_write(sel_wfd *wfd, const void *data, size_t len) +{ + bufchain_add(&wfd->buf, data, len); + return bufchain_size(&wfd->buf); +} + +void sel_wfd_setfd(sel_wfd *wfd, int fd) +{ + wfd->fd = fd; +} + +void sel_rfd_setfd(sel_rfd *rfd, int fd) +{ + rfd->fd = fd; +} + +void sel_rfd_freeze(sel_rfd *rfd) +{ + rfd->frozen = 1; +} + +void sel_rfd_unfreeze(sel_rfd *rfd) +{ + rfd->frozen = 0; +} + +int sel_wfd_delete(sel_wfd *wfd) +{ + sel *sel = wfd->parent; + int ret; + + if (wfd->prev) + wfd->prev->next = wfd->next; + else + sel->whead = wfd->next; + if (wfd->next) + wfd->next->prev = wfd->prev; + else + sel->wtail = wfd->prev; + + bufchain_clear(&wfd->buf); + + ret = wfd->fd; + sfree(wfd); + return ret; +} + +int sel_rfd_delete(sel_rfd *rfd) +{ + sel *sel = rfd->parent; + int ret; + + if (rfd->prev) + rfd->prev->next = rfd->next; + else + sel->rhead = rfd->next; + if (rfd->next) + rfd->next->prev = rfd->prev; + else + sel->rtail = rfd->prev; + + ret = rfd->fd; + sfree(rfd); + return ret; +} + +void sel_free(sel *sel) +{ + while (sel->whead) + sel_wfd_delete(sel->whead); + while (sel->rhead) + sel_rfd_delete(sel->rhead); + sfree(sel); +} + +void *sel_get_ctx(sel *sel) { return sel->ctx; } +void sel_set_ctx(sel *sel, void *ctx) { sel->ctx = ctx; } +void *sel_wfd_get_ctx(sel_wfd *wfd) { return wfd->ctx; } +void sel_wfd_set_ctx(sel_wfd *wfd, void *ctx) { wfd->ctx = ctx; } +void *sel_rfd_get_ctx(sel_rfd *rfd) { return rfd->ctx; } +void sel_rfd_set_ctx(sel_rfd *rfd, void *ctx) { rfd->ctx = ctx; } + +int sel_iterate(sel *sel, long timeout) +{ + sel_rfd *rfd; + sel_wfd *wfd; + fd_set rset, wset; + int maxfd = 0; + struct timeval tv, *ptv; + char buf[65536]; + int ret; + + FD_ZERO(&rset); + FD_ZERO(&wset); + + for (rfd = sel->rhead; rfd; rfd = rfd->next) { + if (rfd->fd >= 0 && !rfd->frozen) { + FD_SET(rfd->fd, &rset); + if (maxfd < rfd->fd + 1) + maxfd = rfd->fd + 1; + } + } + + for (wfd = sel->whead; wfd; wfd = wfd->next) { + if (wfd->fd >= 0 && bufchain_size(&wfd->buf)) { + FD_SET(wfd->fd, &wset); + if (maxfd < wfd->fd + 1) + maxfd = wfd->fd + 1; + } + } + + if (timeout < 0) { + ptv = NULL; + } else { + ptv = &tv; + tv.tv_sec = timeout / 1000; + tv.tv_usec = 1000 * (timeout % 1000); + } + + do { + ret = select(maxfd, &rset, &wset, NULL, ptv); + } while (ret < 0 && (errno == EINTR || errno == EAGAIN)); + + if (ret < 0) + return errno; + + /* + * Just in case one of the callbacks destroys an rfd or wfd we + * had yet to get round to, we must loop from the start every + * single time. Algorithmically irritating, but necessary + * unless we want to store the rfd structures in a heavyweight + * tree sorted by fd. And let's face it, if we cared about + * good algorithmic complexity it's not at all clear we'd be + * using select in the first place. + */ + do { + for (wfd = sel->whead; wfd; wfd = wfd->next) + if (wfd->fd >= 0 && FD_ISSET(wfd->fd, &wset)) { + void *data; + size_t len; + + FD_CLR(wfd->fd, &wset); + bufchain_prefix(&wfd->buf, &data, &len); + ret = write(wfd->fd, data, len); + assert(ret != 0); + if (ret < 0) { + if (wfd->writeerr) + wfd->writeerr(wfd, errno); + } else { + bufchain_consume(&wfd->buf, len); + if (wfd->written) + wfd->written(wfd, bufchain_size(&wfd->buf)); + } + break; + } + } while (wfd); + do { + for (rfd = sel->rhead; rfd; rfd = rfd->next) + if (rfd->fd >= 0 && !rfd->frozen && FD_ISSET(rfd->fd, &rset)) { + FD_CLR(rfd->fd, &rset); + ret = read(rfd->fd, buf, sizeof(buf)); + if (ret < 0) { + if (rfd->readerr) + rfd->readerr(rfd, errno); + } else { + if (rfd->readdata) + rfd->readdata(rfd, buf, ret); + } + break; + } + } while (rfd); + + return 0; +} diff --git a/contrib/cygtermd/sel.h b/contrib/cygtermd/sel.h new file mode 100644 index 00000000..98767e2f --- /dev/null +++ b/contrib/cygtermd/sel.h @@ -0,0 +1,161 @@ +/* + * sel.h: subsystem to manage the grubby details of a select loop, + * buffering data to write, and performing the actual writes and + * reads. + */ + +#ifndef FIXME_SEL_H +#define FIXME_SEL_H + +typedef struct sel sel; +typedef struct sel_wfd sel_wfd; +typedef struct sel_rfd sel_rfd; + +/* + * Callback called when some data is written to a wfd. "bufsize" + * is the remaining quantity of data buffered in that wfd. + */ +typedef void (*sel_written_fn_t)(sel_wfd *wfd, size_t bufsize); + +/* + * Callback called when an error occurs on a wfd, preventing + * further writing to it. "error" is the errno value. + */ +typedef void (*sel_writeerr_fn_t)(sel_wfd *wfd, int error); + +/* + * Callback called when some data is read from an rfd. On EOF, + * this will be called with len==0. + */ +typedef void (*sel_readdata_fn_t)(sel_rfd *rfd, void *data, size_t len); + +/* + * Callback called when an error occurs on an rfd, preventing + * further reading from it. "error" is the errno value. + */ +typedef void (*sel_readerr_fn_t)(sel_rfd *rfd, int error); + +/* + * Create a sel structure, which will oversee a select loop. + * + * "ctx" is user-supplied data stored in the sel structure; it can + * be read and written with sel_get_ctx() and sel_set_ctx(). + */ +sel *sel_new(void *ctx); + +/* + * Add a new fd for writing. Returns a sel_wfd which identifies + * that fd in the sel structure, e.g. for putting data into its + * output buffer. + * + * "ctx" is user-supplied data stored in the sel structure; it can + * be read and written with sel_wfd_get_ctx() and sel_wfd_set_ctx(). + * + * "written" and "writeerr" are called from the event loop when + * things happen. + * + * The fd passed in can be -1, in which case it will be assumed to + * be unwritable at all times. An actual fd can be passed in later + * using sel_wfd_setfd. + */ +sel_wfd *sel_wfd_add(sel *sel, int fd, + sel_written_fn_t written, sel_writeerr_fn_t writeerr, + void *ctx); + +/* + * Add a new fd for reading. Returns a sel_rfd which identifies + * that fd in the sel structure. + * + * "ctx" is user-supplied data stored in the sel structure; it can + * be read and written with sel_rfd_get_ctx() and sel_rfd_set_ctx(). + * + * "readdata" and "readerr" are called from the event loop when + * things happen. "ctx" is passed to both of them. + */ +sel_rfd *sel_rfd_add(sel *sel, int fd, + sel_readdata_fn_t readdata, sel_readerr_fn_t readerr, + void *ctx); + +/* + * Write data into the output buffer of a wfd. Returns the new + * size of the output buffer. (You can call it with len==0 if you + * just want to know the buffer size; in that situation data==NULL + * is also safe.) + */ +size_t sel_write(sel_wfd *wfd, const void *data, size_t len); + +/* + * Freeze and unfreeze an rfd. When frozen, sel will temporarily + * not attempt to read from it, but all its state is retained so + * it can be conveniently unfrozen later. (You might use this + * facility, for instance, if what you were doing with the + * incoming data could only accept it at a certain rate: freeze + * the rfd when you've got lots of backlog, and unfreeze it again + * when things get calmer.) + */ +void sel_rfd_freeze(sel_rfd *rfd); +void sel_rfd_unfreeze(sel_rfd *rfd); + +/* + * Delete a wfd structure from its containing sel. Returns the + * underlying fd, which the client may now consider itself to own + * once more. + */ +int sel_wfd_delete(sel_wfd *wfd); + +/* + * Delete an rfd structure from its containing sel. Returns the + * underlying fd, which the client may now consider itself to own + * once more. + */ +int sel_rfd_delete(sel_rfd *rfd); + +/* + * NOT IMPLEMENTED YET: useful functions here might be ones which + * enumerated all the wfds/rfds in a sel structure in some + * fashion, so you could go through them and remove them all while + * doing sensible things to them. Or, at the very least, just + * return an arbitrary one of the wfds/rfds. + */ + +/* + * Free a sel structure and all its remaining wfds and rfds. + */ +void sel_free(sel *sel); + +/* + * Read and write the ctx parameters in sel, sel_wfd and sel_rfd. + */ +void *sel_get_ctx(sel *sel); +void sel_set_ctx(sel *sel, void *ctx); +void *sel_wfd_get_ctx(sel_wfd *wfd); +void sel_wfd_set_ctx(sel_wfd *wfd, void *ctx); +void *sel_rfd_get_ctx(sel_rfd *rfd); +void sel_rfd_set_ctx(sel_rfd *rfd, void *ctx); + +/* + * Run one iteration of the sel event loop, calling callbacks as + * necessary. Returns zero on success; in the event of a fatal + * error, returns the errno value. + * + * "timeout" is a value in microseconds to limit the length of the + * select call. Less than zero means to wait indefinitely. + */ +int sel_iterate(sel *sel, long timeout); + +/* + * Change the underlying fd in a wfd. If set to -1, no write + * attempts will take place and the wfd's buffer will simply store + * everything passed to sel_write(). If later set to something + * other than -1, all that buffered data will become eligible for + * real writing. + */ +void sel_wfd_setfd(sel_wfd *wfd, int fd); + +/* + * Change the underlying fd in a rfd. If set to -1, no read + * attempts will take place. + */ +void sel_rfd_setfd(sel_rfd *rfd, int fd); + +#endif /* FIXME_SEL_H */ diff --git a/contrib/cygtermd/telnet.c b/contrib/cygtermd/telnet.c new file mode 100644 index 00000000..9fd40706 --- /dev/null +++ b/contrib/cygtermd/telnet.c @@ -0,0 +1,570 @@ +/* + * Simple Telnet server code, adapted from PuTTY's own Telnet + * client code for use as a Cygwin local pty proxy. + */ + +#include +#include +#include + +#include "sel.h" +#include "telnet.h" +#include "malloc.h" +#include "pty.h" + +#ifndef FALSE +#define FALSE 0 +#endif +#ifndef TRUE +#define TRUE 1 +#endif + +#define IAC 255 /* interpret as command: */ +#define DONT 254 /* you are not to use option */ +#define DO 253 /* please, you use option */ +#define WONT 252 /* I won't use option */ +#define WILL 251 /* I will use option */ +#define SB 250 /* interpret as subnegotiation */ +#define SE 240 /* end sub negotiation */ + +#define GA 249 /* you may reverse the line */ +#define EL 248 /* erase the current line */ +#define EC 247 /* erase the current character */ +#define AYT 246 /* are you there */ +#define AO 245 /* abort output--but let prog finish */ +#define IP 244 /* interrupt process--permanently */ +#define BREAK 243 /* break */ +#define DM 242 /* data mark--for connect. cleaning */ +#define NOP 241 /* nop */ +#define EOR 239 /* end of record (transparent mode) */ +#define ABORT 238 /* Abort process */ +#define SUSP 237 /* Suspend process */ +#define xEOF 236 /* End of file: EOF is already used... */ + +#define TELOPTS(X) \ + X(BINARY, 0) /* 8-bit data path */ \ + X(ECHO, 1) /* echo */ \ + X(RCP, 2) /* prepare to reconnect */ \ + X(SGA, 3) /* suppress go ahead */ \ + X(NAMS, 4) /* approximate message size */ \ + X(STATUS, 5) /* give status */ \ + X(TM, 6) /* timing mark */ \ + X(RCTE, 7) /* remote controlled transmission and echo */ \ + X(NAOL, 8) /* negotiate about output line width */ \ + X(NAOP, 9) /* negotiate about output page size */ \ + X(NAOCRD, 10) /* negotiate about CR disposition */ \ + X(NAOHTS, 11) /* negotiate about horizontal tabstops */ \ + X(NAOHTD, 12) /* negotiate about horizontal tab disposition */ \ + X(NAOFFD, 13) /* negotiate about formfeed disposition */ \ + X(NAOVTS, 14) /* negotiate about vertical tab stops */ \ + X(NAOVTD, 15) /* negotiate about vertical tab disposition */ \ + X(NAOLFD, 16) /* negotiate about output LF disposition */ \ + X(XASCII, 17) /* extended ascic character set */ \ + X(LOGOUT, 18) /* force logout */ \ + X(BM, 19) /* byte macro */ \ + X(DET, 20) /* data entry terminal */ \ + X(SUPDUP, 21) /* supdup protocol */ \ + X(SUPDUPOUTPUT, 22) /* supdup output */ \ + X(SNDLOC, 23) /* send location */ \ + X(TTYPE, 24) /* terminal type */ \ + X(EOR, 25) /* end or record */ \ + X(TUID, 26) /* TACACS user identification */ \ + X(OUTMRK, 27) /* output marking */ \ + X(TTYLOC, 28) /* terminal location number */ \ + X(3270REGIME, 29) /* 3270 regime */ \ + X(X3PAD, 30) /* X.3 PAD */ \ + X(NAWS, 31) /* window size */ \ + X(TSPEED, 32) /* terminal speed */ \ + X(LFLOW, 33) /* remote flow control */ \ + X(LINEMODE, 34) /* Linemode option */ \ + X(XDISPLOC, 35) /* X Display Location */ \ + X(OLD_ENVIRON, 36) /* Old - Environment variables */ \ + X(AUTHENTICATION, 37) /* Authenticate */ \ + X(ENCRYPT, 38) /* Encryption option */ \ + X(NEW_ENVIRON, 39) /* New - Environment variables */ \ + X(TN3270E, 40) /* TN3270 enhancements */ \ + X(XAUTH, 41) \ + X(CHARSET, 42) /* Character set */ \ + X(RSP, 43) /* Remote serial port */ \ + X(COM_PORT_OPTION, 44) /* Com port control */ \ + X(SLE, 45) /* Suppress local echo */ \ + X(STARTTLS, 46) /* Start TLS */ \ + X(KERMIT, 47) /* Automatic Kermit file transfer */ \ + X(SEND_URL, 48) \ + X(FORWARD_X, 49) \ + X(PRAGMA_LOGON, 138) \ + X(SSPI_LOGON, 139) \ + X(PRAGMA_HEARTBEAT, 140) \ + X(EXOPL, 255) /* extended-options-list */ + +#define telnet_enum(x,y) TELOPT_##x = y, +enum { TELOPTS(telnet_enum) dummy=0 }; +#undef telnet_enum + +#define TELQUAL_IS 0 /* option is... */ +#define TELQUAL_SEND 1 /* send option */ +#define TELQUAL_INFO 2 /* ENVIRON: informational version of IS */ +#define BSD_VAR 1 +#define BSD_VALUE 0 +#define RFC_VAR 0 +#define RFC_VALUE 1 + +#define CR 13 +#define LF 10 +#define NUL 0 + +#define iswritable(x) ( (x) != IAC && (x) != CR ) + +static char *telopt(int opt) +{ +#define telnet_str(x,y) case TELOPT_##x: return #x; + switch (opt) { + TELOPTS(telnet_str) + default: + return ""; + } +#undef telnet_str +} + +static void telnet_size(void *handle, int width, int height); + +struct Opt { + int send; /* what we initially send */ + int nsend; /* -ve send if requested to stop it */ + int ack, nak; /* +ve and -ve acknowledgements */ + int option; /* the option code */ + int index; /* index into telnet->opt_states[] */ + enum { + REQUESTED, ACTIVE, INACTIVE, REALLY_INACTIVE + } initial_state; +}; + +enum { + OPTINDEX_NAWS, + OPTINDEX_TSPEED, + OPTINDEX_TTYPE, + OPTINDEX_OENV, + OPTINDEX_NENV, + OPTINDEX_ECHO, + OPTINDEX_WE_SGA, + OPTINDEX_THEY_SGA, + OPTINDEX_WE_BIN, + OPTINDEX_THEY_BIN, + NUM_OPTS +}; + +static const struct Opt o_naws = + { DO, DONT, WILL, WONT, TELOPT_NAWS, OPTINDEX_NAWS, REQUESTED }; +static const struct Opt o_ttype = + { DO, DONT, WILL, WONT, TELOPT_TTYPE, OPTINDEX_TTYPE, REQUESTED }; +static const struct Opt o_oenv = + { DO, DONT, WILL, WONT, TELOPT_OLD_ENVIRON, OPTINDEX_OENV, INACTIVE }; +static const struct Opt o_nenv = + { DO, DONT, WILL, WONT, TELOPT_NEW_ENVIRON, OPTINDEX_NENV, REQUESTED }; +static const struct Opt o_echo = + { WILL, WONT, DO, DONT, TELOPT_ECHO, OPTINDEX_ECHO, REQUESTED }; +static const struct Opt o_they_sga = + { DO, DONT, WILL, WONT, TELOPT_SGA, OPTINDEX_WE_SGA, REQUESTED }; +static const struct Opt o_we_sga = + { WILL, WONT, DO, DONT, TELOPT_SGA, OPTINDEX_THEY_SGA, REQUESTED }; + +static const struct Opt *const opts[] = { + &o_echo, &o_we_sga, &o_they_sga, &o_naws, &o_ttype, &o_oenv, &o_nenv, NULL +}; + +struct telnet_tag { + int opt_states[NUM_OPTS]; + + int sb_opt, sb_len; + unsigned char *sb_buf; + int sb_size; + + enum { + TOP_LEVEL, SEENIAC, SEENWILL, SEENWONT, SEENDO, SEENDONT, + SEENSB, SUBNEGOT, SUBNEG_IAC, SEENCR + } state; + + sel_wfd *net, *pty; + + /* + * Options we must finish processing before launching the shell + */ + int old_environ_done, new_environ_done, ttype_done; + + /* + * Ready to start shell? + */ + int shell_ok; + int envvarsize; + struct shell_data shdata; +}; + +#define TELNET_MAX_BACKLOG 4096 + +#define SB_DELTA 1024 + +static void send_opt(Telnet telnet, int cmd, int option) +{ + unsigned char b[3]; + + b[0] = IAC; + b[1] = cmd; + b[2] = option; + sel_write(telnet->net, (char *)b, 3); +} + +static void deactivate_option(Telnet telnet, const struct Opt *o) +{ + if (telnet->opt_states[o->index] == REQUESTED || + telnet->opt_states[o->index] == ACTIVE) + send_opt(telnet, o->nsend, o->option); + telnet->opt_states[o->index] = REALLY_INACTIVE; +} + +/* + * Generate side effects of enabling or disabling an option. + */ +static void option_side_effects(Telnet telnet, const struct Opt *o, int enabled) +{ +} + +static void activate_option(Telnet telnet, const struct Opt *o) +{ + if (o->option == TELOPT_NEW_ENVIRON || + o->option == TELOPT_OLD_ENVIRON || + o->option == TELOPT_TTYPE) { + char buf[6]; + buf[0] = IAC; + buf[1] = SB; + buf[2] = o->option; + buf[3] = TELQUAL_SEND; + buf[4] = IAC; + buf[5] = SE; + sel_write(telnet->net, buf, 6); + } + option_side_effects(telnet, o, 1); +} + +static void done_option(Telnet telnet, int option) +{ + if (option == TELOPT_OLD_ENVIRON) + telnet->old_environ_done = 1; + else if (option == TELOPT_NEW_ENVIRON) + telnet->new_environ_done = 1; + else if (option == TELOPT_TTYPE) + telnet->ttype_done = 1; + + if (telnet->old_environ_done && telnet->new_environ_done && + telnet->ttype_done) { + telnet->shell_ok = 1; + } +} + +static void refused_option(Telnet telnet, const struct Opt *o) +{ + done_option(telnet, o->option); + if (o->send == WILL && o->option == TELOPT_NEW_ENVIRON && + telnet->opt_states[o_oenv.index] == INACTIVE) { + send_opt(telnet, WILL, TELOPT_OLD_ENVIRON); + telnet->opt_states[o_oenv.index] = REQUESTED; + telnet->old_environ_done = 0; + } + option_side_effects(telnet, o, 0); +} + +static void proc_rec_opt(Telnet telnet, int cmd, int option) +{ + const struct Opt *const *o; + + for (o = opts; *o; o++) { + if ((*o)->option == option && (*o)->ack == cmd) { + switch (telnet->opt_states[(*o)->index]) { + case REQUESTED: + telnet->opt_states[(*o)->index] = ACTIVE; + activate_option(telnet, *o); + break; + case ACTIVE: + break; + case INACTIVE: + telnet->opt_states[(*o)->index] = ACTIVE; + send_opt(telnet, (*o)->send, option); + activate_option(telnet, *o); + break; + case REALLY_INACTIVE: + send_opt(telnet, (*o)->nsend, option); + break; + } + return; + } else if ((*o)->option == option && (*o)->nak == cmd) { + switch (telnet->opt_states[(*o)->index]) { + case REQUESTED: + telnet->opt_states[(*o)->index] = INACTIVE; + refused_option(telnet, *o); + break; + case ACTIVE: + telnet->opt_states[(*o)->index] = INACTIVE; + send_opt(telnet, (*o)->nsend, option); + option_side_effects(telnet, *o, 0); + break; + case INACTIVE: + case REALLY_INACTIVE: + break; + } + return; + } + } + /* + * If we reach here, the option was one we weren't prepared to + * cope with. If the request was positive (WILL or DO), we send + * a negative ack to indicate refusal. If the request was + * negative (WONT / DONT), we must do nothing. + */ + if (cmd == WILL || cmd == DO) + send_opt(telnet, (cmd == WILL ? DONT : WONT), option); +} + +static void process_subneg(Telnet telnet) +{ + unsigned char b[2048], *p, *q; + int var, value, n; + char *e; + + switch (telnet->sb_opt) { + case TELOPT_OLD_ENVIRON: + case TELOPT_NEW_ENVIRON: + if (telnet->sb_buf[0] == TELQUAL_IS) { + if (telnet->sb_opt == TELOPT_NEW_ENVIRON) { + var = RFC_VAR; + value = RFC_VALUE; + } else { + if (telnet->sb_len > 1 && !(telnet->sb_buf[0] &~ 1)) { + var = telnet->sb_buf[0]; + value = BSD_VAR ^ BSD_VALUE ^ var; + } else { + var = BSD_VAR; + value = BSD_VALUE; + } + } + } + n = 1; + while (n < telnet->sb_len && telnet->sb_buf[n] == var) { + int varpos, varlen, valpos, vallen; + char *result; + + varpos = ++n; + while (n < telnet->sb_len && telnet->sb_buf[n] != value) + n++; + if (n == telnet->sb_len) + break; + varlen = n - varpos; + valpos = ++n; + while (n < telnet->sb_len && telnet->sb_buf[n] != var) + n++; + vallen = n - valpos; + + result = snewn(varlen + vallen + 2, char); + sprintf(result, "%.*s=%.*s", + varlen, telnet->sb_buf+varpos, + vallen, telnet->sb_buf+valpos); + if (telnet->shdata.nenvvars >= telnet->envvarsize) { + telnet->envvarsize = telnet->shdata.nenvvars * 3 / 2 + 16; + telnet->shdata.envvars = sresize(telnet->shdata.envvars, + telnet->envvarsize, char *); + } + telnet->shdata.envvars[telnet->shdata.nenvvars++] = result; + } + done_option(telnet, telnet->sb_opt); + break; + case TELOPT_TTYPE: + if (telnet->sb_len >= 1 && telnet->sb_buf[0] == TELQUAL_IS) { + telnet->shdata.termtype = snewn(5 + telnet->sb_len, char); + strcpy(telnet->shdata.termtype, "TERM="); + for (n = 0; n < telnet->sb_len-1; n++) { + char c = telnet->sb_buf[n+1]; + if (c >= 'A' && c <= 'Z') + c = c + 'a' - 'A'; + telnet->shdata.termtype[n+5] = c; + } + telnet->shdata.termtype[telnet->sb_len+5-1] = '\0'; + } + done_option(telnet, telnet->sb_opt); + break; + case TELOPT_NAWS: + if (telnet->sb_len == 4) { + int w, h; + w = (unsigned char)telnet->sb_buf[0]; + w = (w << 8) | (unsigned char)telnet->sb_buf[1]; + h = (unsigned char)telnet->sb_buf[2]; + h = (h << 8) | (unsigned char)telnet->sb_buf[3]; + pty_resize(w, h); + } + break; + } +} + +void telnet_from_net(Telnet telnet, char *buf, int len) +{ + while (len--) { + int c = (unsigned char) *buf++; + + switch (telnet->state) { + case TOP_LEVEL: + case SEENCR: + /* + * PuTTY sends Telnet's new line sequence (CR LF on + * the wire) in response to the return key. We must + * therefore treat that as equivalent to CR NUL, and + * send CR to the pty. + */ + if ((c == NUL || c == '\n') && telnet->state == SEENCR) + telnet->state = TOP_LEVEL; + else if (c == IAC) + telnet->state = SEENIAC; + else { + char cc = c; + sel_write(telnet->pty, &cc, 1); + + telnet->state = SEENCR; + } + break; + case SEENIAC: + if (c == DO) + telnet->state = SEENDO; + else if (c == DONT) + telnet->state = SEENDONT; + else if (c == WILL) + telnet->state = SEENWILL; + else if (c == WONT) + telnet->state = SEENWONT; + else if (c == SB) + telnet->state = SEENSB; + else if (c == DM) + telnet->state = TOP_LEVEL; + else { + /* ignore everything else; print it if it's IAC */ + if (c == IAC) { + char cc = c; + sel_write(telnet->pty, &cc, 1); + } + telnet->state = TOP_LEVEL; + } + break; + case SEENWILL: + proc_rec_opt(telnet, WILL, c); + telnet->state = TOP_LEVEL; + break; + case SEENWONT: + proc_rec_opt(telnet, WONT, c); + telnet->state = TOP_LEVEL; + break; + case SEENDO: + proc_rec_opt(telnet, DO, c); + telnet->state = TOP_LEVEL; + break; + case SEENDONT: + proc_rec_opt(telnet, DONT, c); + telnet->state = TOP_LEVEL; + break; + case SEENSB: + telnet->sb_opt = c; + telnet->sb_len = 0; + telnet->state = SUBNEGOT; + break; + case SUBNEGOT: + if (c == IAC) + telnet->state = SUBNEG_IAC; + else { + subneg_addchar: + if (telnet->sb_len >= telnet->sb_size) { + telnet->sb_size += SB_DELTA; + telnet->sb_buf = sresize(telnet->sb_buf, telnet->sb_size, + unsigned char); + } + telnet->sb_buf[telnet->sb_len++] = c; + telnet->state = SUBNEGOT; /* in case we came here by goto */ + } + break; + case SUBNEG_IAC: + if (c != SE) + goto subneg_addchar; /* yes, it's a hack, I know, but... */ + else { + process_subneg(telnet); + telnet->state = TOP_LEVEL; + } + break; + } + } +} + +Telnet telnet_new(sel_wfd *net, sel_wfd *pty) +{ + Telnet telnet; + + telnet = snew(struct telnet_tag); + telnet->sb_buf = NULL; + telnet->sb_size = 0; + telnet->state = TOP_LEVEL; + telnet->net = net; + telnet->pty = pty; + telnet->shdata.envvars = NULL; + telnet->shdata.nenvvars = telnet->envvarsize = 0; + telnet->shdata.termtype = NULL; + + /* + * Initialise option states. + */ + { + const struct Opt *const *o; + + for (o = opts; *o; o++) { + telnet->opt_states[(*o)->index] = (*o)->initial_state; + if (telnet->opt_states[(*o)->index] == REQUESTED) + send_opt(telnet, (*o)->send, (*o)->option); + } + } + + telnet->old_environ_done = 1; /* initially don't want to bother */ + telnet->new_environ_done = 0; + telnet->ttype_done = 0; + telnet->shell_ok = 0; + + return telnet; +} + +void telnet_free(Telnet telnet) +{ + sfree(telnet->sb_buf); + sfree(telnet); +} + +void telnet_from_pty(Telnet telnet, char *buf, int len) +{ + unsigned char *p, *end; + static const unsigned char iac[2] = { IAC, IAC }; + static const unsigned char cr[2] = { CR, NUL }; +#if 0 + static const unsigned char nl[2] = { CR, LF }; +#endif + + p = (unsigned char *)buf; + end = (unsigned char *)(buf + len); + while (p < end) { + unsigned char *q = p; + + while (p < end && iswritable(*p)) + p++; + sel_write(telnet->net, (char *)q, p - q); + + while (p < end && !iswritable(*p)) { + sel_write(telnet->net, (char *)(*p == IAC ? iac : cr), 2); + p++; + } + } +} + +int telnet_shell_ok(Telnet telnet, struct shell_data *shdata) +{ + if (telnet->shell_ok) + *shdata = telnet->shdata; /* structure copy */ + return telnet->shell_ok; +} diff --git a/contrib/cygtermd/telnet.h b/contrib/cygtermd/telnet.h new file mode 100644 index 00000000..1a74cab1 --- /dev/null +++ b/contrib/cygtermd/telnet.h @@ -0,0 +1,41 @@ +/* + * Header declaring Telnet-handling functions. + */ + +#ifndef FIXME_TELNET_H +#define FIXME_TELNET_H + +#include "sel.h" + +typedef struct telnet_tag *Telnet; + +struct shell_data { + char **envvars; /* array of "VAR=value" terms */ + int nenvvars; + char *termtype; +}; + +/* + * Create and destroy a Telnet structure. + */ +Telnet telnet_new(sel_wfd *net, sel_wfd *pty); +void telnet_free(Telnet telnet); + +/* + * Process data read from the pty. + */ +void telnet_from_pty(Telnet telnet, char *buf, int len); + +/* + * Process Telnet protocol data received from the network. + */ +void telnet_from_net(Telnet telnet, char *buf, int len); + +/* + * Return true if pre-shell-startup negotiations are complete and + * it's safe to start the shell subprocess now. On a true return, + * also fills in the shell_data structure. + */ +int telnet_shell_ok(Telnet telnet, struct shell_data *shdata); + +#endif /* FIXME_TELNET_H */ -- 2.11.0