X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/edd0cb8aef57080ae884e06731a7892ca8cdba44..b61f81bc4c102d06f13fd68e4a73ab8fdfdb3cf5:/unix/uxcons.c diff --git a/unix/uxcons.c b/unix/uxcons.c index d4848a6a..ce1a4923 100644 --- a/unix/uxcons.c +++ b/unix/uxcons.c @@ -7,8 +7,10 @@ #include #include #include + #include #include +#include #include "putty.h" #include "storage.h" @@ -18,6 +20,31 @@ int console_batch_mode = FALSE; static void *console_logctx = NULL; +static struct termios orig_termios_stderr; +static int stderr_is_a_tty; + +void stderr_tty_init() +{ + /* Ensure that if stderr is a tty, we can get it back to a sane state. */ + if ((flags & FLAG_STDERR_TTY) && isatty(STDERR_FILENO)) { + stderr_is_a_tty = TRUE; + tcgetattr(STDERR_FILENO, &orig_termios_stderr); + } +} + +void premsg(struct termios *cf) +{ + if (stderr_is_a_tty) { + tcgetattr(STDERR_FILENO, cf); + tcsetattr(STDERR_FILENO, TCSADRAIN, &orig_termios_stderr); + } +} +void postmsg(struct termios *cf) +{ + if (stderr_is_a_tty) + tcsetattr(STDERR_FILENO, TCSADRAIN, cf); +} + /* * Clean up and exit. */ @@ -101,6 +128,7 @@ int verify_ssh_host_key(void *frontend, char *host, int port, char *keytype, static const char abandoned[] = "Connection abandoned.\n"; char line[32]; + struct termios cf; /* * Verify the key. @@ -110,6 +138,7 @@ int verify_ssh_host_key(void *frontend, char *host, int port, char *keytype, if (ret == 0) /* success - key matched OK */ return 1; + premsg(&cf); if (ret == 2) { /* key was different */ if (console_batch_mode) { fprintf(stderr, wrongmsg_batch, keytype, fingerprint); @@ -134,16 +163,19 @@ int verify_ssh_host_key(void *frontend, char *host, int port, char *keytype, newmode.c_lflag |= ECHO | ISIG | ICANON; tcsetattr(0, TCSANOW, &newmode); line[0] = '\0'; - read(0, line, sizeof(line) - 1); + if (read(0, line, sizeof(line) - 1) <= 0) + /* handled below */; tcsetattr(0, TCSANOW, &oldmode); } if (line[0] != '\0' && line[0] != '\r' && line[0] != '\n') { if (line[0] == 'y' || line[0] == 'Y') store_host_key(host, port, keytype, keystr); + postmsg(&cf); return 1; } else { fprintf(stderr, abandoned); + postmsg(&cf); return 0; } } @@ -166,7 +198,9 @@ int askalg(void *frontend, const char *algtype, const char *algname, static const char abandoned[] = "Connection abandoned.\n"; char line[32]; + struct termios cf; + premsg(&cf); if (console_batch_mode) { fprintf(stderr, msg_batch, algtype, algname); return 0; @@ -182,14 +216,17 @@ int askalg(void *frontend, const char *algtype, const char *algname, newmode.c_lflag |= ECHO | ISIG | ICANON; tcsetattr(0, TCSANOW, &newmode); line[0] = '\0'; - read(0, line, sizeof(line) - 1); + if (read(0, line, sizeof(line) - 1) <= 0) + /* handled below */; tcsetattr(0, TCSANOW, &oldmode); } if (line[0] == 'y' || line[0] == 'Y') { + postmsg(&cf); return 1; } else { fprintf(stderr, abandoned); + postmsg(&cf); return 0; } } @@ -198,7 +235,7 @@ int askalg(void *frontend, const char *algtype, const char *algname, * Ask whether to wipe a session log file before writing to it. * Returns 2 for wipe, 1 for append, 0 for cancel (don't log). */ -int askappend(void *frontend, Filename filename, +int askappend(void *frontend, Filename *filename, void (*callback)(void *ctx, int result), void *ctx) { static const char msgtemplate[] = @@ -215,13 +252,15 @@ int askappend(void *frontend, Filename filename, "Logging will not be enabled.\n"; char line[32]; + struct termios cf; + premsg(&cf); if (console_batch_mode) { - fprintf(stderr, msgtemplate_batch, FILENAME_MAX, filename.path); + fprintf(stderr, msgtemplate_batch, FILENAME_MAX, filename->path); fflush(stderr); return 0; } - fprintf(stderr, msgtemplate, FILENAME_MAX, filename.path); + fprintf(stderr, msgtemplate, FILENAME_MAX, filename->path); fflush(stderr); { @@ -231,10 +270,12 @@ int askappend(void *frontend, Filename filename, newmode.c_lflag |= ECHO | ISIG | ICANON; tcsetattr(0, TCSANOW, &newmode); line[0] = '\0'; - read(0, line, sizeof(line) - 1); + if (read(0, line, sizeof(line) - 1) <= 0) + /* handled below */; tcsetattr(0, TCSANOW, &oldmode); } + postmsg(&cf); if (line[0] == 'y' || line[0] == 'Y') return 2; else if (line[0] == 'n' || line[0] == 'N') @@ -266,7 +307,10 @@ void old_keyfile_warning(void) "Once the key is loaded into PuTTYgen, you can perform\n" "this conversion simply by saving it again.\n"; + struct termios cf; + premsg(&cf); fputs(message, stderr); + postmsg(&cf); } void console_provide_logctx(void *logctx) @@ -276,22 +320,53 @@ void console_provide_logctx(void *logctx) void logevent(void *frontend, const char *string) { + struct termios cf; + premsg(&cf); if (console_logctx) log_eventlog(console_logctx, string); + postmsg(&cf); +} + +/* + * Special functions to read and print to the console for password + * prompts and the like. Uses /dev/tty or stdin/stderr, in that order + * of preference; also sanitises escape sequences out of the text, on + * the basis that it might have been sent by a hostile SSH server + * doing malicious keyboard-interactive. + */ +static void console_open(FILE **outfp, int *infd) +{ + int fd; + + if ((fd = open("/dev/tty", O_RDWR)) >= 0) { + *infd = fd; + *outfp = fdopen(*infd, "w"); + } else { + *infd = 0; + *outfp = stderr; + } +} +static void console_close(FILE *outfp, int infd) +{ + if (outfp != stderr) + fclose(outfp); /* will automatically close infd too */ } -static void console_data_untrusted(const char *data, int len) +static void console_prompt_text(FILE *outfp, const char *data, int len) { int i; + for (i = 0; i < len; i++) if ((data[i] & 0x60) || (data[i] == '\n')) - fputc(data[i], stdout); - fflush(stdout); + fputc(data[i], outfp); + fflush(outfp); } int console_get_userpass_input(prompts_t *p, unsigned char *in, int inlen) { size_t curr_prompt; + FILE *outfp = NULL; + int infd; /* * Zero all the results, in case we abort half-way through. @@ -299,62 +374,82 @@ int console_get_userpass_input(prompts_t *p, unsigned char *in, int inlen) { int i; for (i = 0; i < p->n_prompts; i++) - memset(p->prompts[i]->result, 0, p->prompts[i]->result_len); + prompt_set_result(p->prompts[i], ""); } - if (console_batch_mode) + if (p->n_prompts && console_batch_mode) return 0; + console_open(&outfp, &infd); + /* * Preamble. */ /* We only print the `name' caption if we have to... */ if (p->name_reqd && p->name) { size_t l = strlen(p->name); - console_data_untrusted(p->name, l); + console_prompt_text(outfp, p->name, l); if (p->name[l-1] != '\n') - console_data_untrusted("\n", 1); + console_prompt_text(outfp, "\n", 1); } /* ...but we always print any `instruction'. */ if (p->instruction) { size_t l = strlen(p->instruction); - console_data_untrusted(p->instruction, l); + console_prompt_text(outfp, p->instruction, l); if (p->instruction[l-1] != '\n') - console_data_untrusted("\n", 1); + console_prompt_text(outfp, "\n", 1); } for (curr_prompt = 0; curr_prompt < p->n_prompts; curr_prompt++) { struct termios oldmode, newmode; - int i; + int len; prompt_t *pr = p->prompts[curr_prompt]; - tcgetattr(0, &oldmode); + tcgetattr(infd, &oldmode); newmode = oldmode; newmode.c_lflag |= ISIG | ICANON; if (!pr->echo) newmode.c_lflag &= ~ECHO; else newmode.c_lflag |= ECHO; - tcsetattr(0, TCSANOW, &newmode); + tcsetattr(infd, TCSANOW, &newmode); - console_data_untrusted(pr->prompt, strlen(pr->prompt)); + console_prompt_text(outfp, pr->prompt, strlen(pr->prompt)); - i = read(0, pr->result, pr->result_len - 1); + len = 0; + while (1) { + int ret; - tcsetattr(0, TCSANOW, &oldmode); + prompt_ensure_result_size(pr, len * 5 / 4 + 512); + ret = read(infd, pr->result + len, pr->resultsize - len - 1); + if (ret <= 0) { + len = -1; + break; + } + len += ret; + if (pr->result[len - 1] == '\n') { + len--; + break; + } + } - if (i > 0 && pr->result[i-1] == '\n') - i--; - pr->result[i] = '\0'; + tcsetattr(infd, TCSANOW, &oldmode); if (!pr->echo) - fputs("\n", stdout); + console_prompt_text(outfp, "\n", 1); + if (len < 0) { + console_close(outfp, infd); + return 0; /* failure due to read error */ + } + + pr->result[len] = '\0'; } - return 1; /* success */ + console_close(outfp, infd); + return 1; /* success */ } void frontend_keypress(void *handle) @@ -374,8 +469,6 @@ int is_interactive(void) * X11-forwarding-related things suitable for console. */ -const char platform_x11_best_transport[] = "unix"; - char *platform_get_x_display(void) { return dupstr(getenv("DISPLAY")); }