putty/misc.c

391 строка
12 KiB
C

/*
* Platform-independent routines shared between all PuTTY programs.
*
* This file contains functions that use the kind of infrastructure
* like conf.c that tends to only live in the main applications, or
* that do things that only something like a main PuTTY application
* would need. So standalone test programs should generally be able to
* avoid linking against it.
*
* More standalone functions that depend on nothing but the C library
* live in utils.c.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <limits.h>
#include <ctype.h>
#include <assert.h>
#include "defs.h"
#include "putty.h"
#include "misc.h"
void seat_connection_fatal(Seat *seat, const char *fmt, ...)
{
va_list ap;
char *msg;
va_start(ap, fmt);
msg = dupvprintf(fmt, ap);
va_end(ap);
seat->vt->connection_fatal(seat, msg);
sfree(msg); /* if we return */
}
prompts_t *new_prompts(void)
{
prompts_t *p = snew(prompts_t);
p->prompts = NULL;
p->n_prompts = p->prompts_size = 0;
p->data = NULL;
p->to_server = true; /* to be on the safe side */
p->name = p->instruction = NULL;
p->name_reqd = p->instr_reqd = false;
return p;
}
void add_prompt(prompts_t *p, char *promptstr, bool echo)
{
prompt_t *pr = snew(prompt_t);
pr->prompt = promptstr;
pr->echo = echo;
pr->result = NULL;
pr->resultsize = 0;
sgrowarray(p->prompts, p->prompts_size, p->n_prompts);
p->prompts[p->n_prompts++] = pr;
}
void prompt_ensure_result_size(prompt_t *pr, int newlen)
{
if ((int)pr->resultsize < newlen) {
char *newbuf;
newlen = newlen * 5 / 4 + 512; /* avoid too many small allocs */
/*
* We don't use sresize / realloc here, because we will be
* storing sensitive stuff like passwords in here, and we want
* to make sure that the data doesn't get copied around in
* memory without the old copy being destroyed.
*/
newbuf = snewn(newlen, char);
memcpy(newbuf, pr->result, pr->resultsize);
smemclr(pr->result, pr->resultsize);
sfree(pr->result);
pr->result = newbuf;
pr->resultsize = newlen;
}
}
void prompt_set_result(prompt_t *pr, const char *newstr)
{
prompt_ensure_result_size(pr, strlen(newstr) + 1);
strcpy(pr->result, newstr);
}
void free_prompts(prompts_t *p)
{
size_t i;
for (i=0; i < p->n_prompts; i++) {
prompt_t *pr = p->prompts[i];
smemclr(pr->result, pr->resultsize); /* burn the evidence */
sfree(pr->result);
sfree(pr->prompt);
sfree(pr);
}
sfree(p->prompts);
sfree(p->name);
sfree(p->instruction);
sfree(p);
}
/*
* Determine whether or not a Conf represents a session which can
* sensibly be launched right now.
*/
bool conf_launchable(Conf *conf)
{
if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
return conf_get_str(conf, CONF_serline)[0] != 0;
else
return conf_get_str(conf, CONF_host)[0] != 0;
}
char const *conf_dest(Conf *conf)
{
if (conf_get_int(conf, CONF_protocol) == PROT_SERIAL)
return conf_get_str(conf, CONF_serline);
else
return conf_get_str(conf, CONF_host);
}
/*
* Validate a manual host key specification (either entered in the
* GUI, or via -hostkey). If valid, we return true, and update 'key'
* to contain a canonicalised version of the key string in 'key'
* (which is guaranteed to take up at most as much space as the
* original version), suitable for putting into the Conf. If not
* valid, we return false.
*/
bool validate_manual_hostkey(char *key)
{
char *p, *q, *r, *s;
/*
* Step through the string word by word, looking for a word that's
* in one of the formats we like.
*/
p = key;
while ((p += strspn(p, " \t"))[0]) {
q = p;
p += strcspn(p, " \t");
if (*p) *p++ = '\0';
/*
* Now q is our word.
*/
if (strlen(q) == 16*3 - 1 &&
q[strspn(q, "0123456789abcdefABCDEF:")] == 0) {
/*
* Might be a key fingerprint. Check the colons are in the
* right places, and if so, return the same fingerprint
* canonicalised into lowercase.
*/
int i;
for (i = 0; i < 16; i++)
if (q[3*i] == ':' || q[3*i+1] == ':')
goto not_fingerprint; /* sorry */
for (i = 0; i < 15; i++)
if (q[3*i+2] != ':')
goto not_fingerprint; /* sorry */
for (i = 0; i < 16*3 - 1; i++)
key[i] = tolower(q[i]);
key[16*3 - 1] = '\0';
return true;
}
not_fingerprint:;
/*
* Before we check for a public-key blob, trim newlines out of
* the middle of the word, in case someone's managed to paste
* in a public-key blob _with_ them.
*/
for (r = s = q; *r; r++)
if (*r != '\n' && *r != '\r')
*s++ = *r;
*s = '\0';
if (strlen(q) % 4 == 0 && strlen(q) > 2*4 &&
q[strspn(q, "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz+/=")] == 0) {
/*
* Might be a base64-encoded SSH-2 public key blob. Check
* that it starts with a sensible algorithm string. No
* canonicalisation is necessary for this string type.
*
* The algorithm string must be at most 64 characters long
* (RFC 4251 section 6).
*/
unsigned char decoded[6];
unsigned alglen;
int minlen;
int len = 0;
len += base64_decode_atom(q, decoded+len);
if (len < 3)
goto not_ssh2_blob; /* sorry */
len += base64_decode_atom(q+4, decoded+len);
if (len < 4)
goto not_ssh2_blob; /* sorry */
alglen = GET_32BIT_MSB_FIRST(decoded);
if (alglen > 64)
goto not_ssh2_blob; /* sorry */
minlen = ((alglen + 4) + 2) / 3;
if (strlen(q) < minlen)
goto not_ssh2_blob; /* sorry */
strcpy(key, q);
return true;
}
not_ssh2_blob:;
}
return false;
}
char *buildinfo(const char *newline)
{
strbuf *buf = strbuf_new();
strbuf_catf(buf, "Build platform: %d-bit %s",
(int)(CHAR_BIT * sizeof(void *)),
BUILDINFO_PLATFORM);
#ifdef __clang_version__
#define FOUND_COMPILER
strbuf_catf(buf, "%sCompiler: clang %s", newline, __clang_version__);
#elif defined __GNUC__ && defined __VERSION__
#define FOUND_COMPILER
strbuf_catf(buf, "%sCompiler: gcc %s", newline, __VERSION__);
#endif
#if defined _MSC_VER
#ifndef FOUND_COMPILER
#define FOUND_COMPILER
strbuf_catf(buf, "%sCompiler: ", newline);
#else
strbuf_catf(buf, ", emulating ");
#endif
strbuf_catf(buf, "Visual Studio", newline);
#if 0
/*
* List of _MSC_VER values and their translations taken from
* https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
* except for 1920, which is not yet listed on that page as of
* 2019-03-22, and was determined experimentally by Sean Kain.
*
* The pointless #if 0 branch containing this comment is there so
* that every real clause can start with #elif and there's no
* anomalous first clause. That way the patch looks nicer when you
* add extra ones.
*/
#elif _MSC_VER == 1920
strbuf_catf(buf, " 2019 (16.x)");
#elif _MSC_VER == 1916
strbuf_catf(buf, " 2017 version 15.9");
#elif _MSC_VER == 1915
strbuf_catf(buf, " 2017 version 15.8");
#elif _MSC_VER == 1914
strbuf_catf(buf, " 2017 version 15.7");
#elif _MSC_VER == 1913
strbuf_catf(buf, " 2017 version 15.6");
#elif _MSC_VER == 1912
strbuf_catf(buf, " 2017 version 15.5");
#elif _MSC_VER == 1911
strbuf_catf(buf, " 2017 version 15.3");
#elif _MSC_VER == 1910
strbuf_catf(buf, " 2017 RTW (15.0)");
#elif _MSC_VER == 1900
strbuf_catf(buf, " 2015 (14.0)");
#elif _MSC_VER == 1800
strbuf_catf(buf, " 2013 (12.0)");
#elif _MSC_VER == 1700
strbuf_catf(buf, " 2012 (11.0)");
#elif _MSC_VER == 1600
strbuf_catf(buf, " 2010 (10.0)");
#elif _MSC_VER == 1500
strbuf_catf(buf, " 2008 (9.0)");
#elif _MSC_VER == 1400
strbuf_catf(buf, " 2005 (8.0)");
#elif _MSC_VER == 1310
strbuf_catf(buf, " .NET 2003 (7.1)");
#elif _MSC_VER == 1300
strbuf_catf(buf, " .NET 2002 (7.0)");
#elif _MSC_VER == 1200
strbuf_catf(buf, " 6.0");
#else
strbuf_catf(buf, ", unrecognised version");
#endif
strbuf_catf(buf, ", _MSC_VER=%d", (int)_MSC_VER);
#endif
#ifdef BUILDINFO_GTK
{
char *gtk_buildinfo = buildinfo_gtk_version();
if (gtk_buildinfo) {
strbuf_catf(buf, "%sCompiled against GTK version %s",
newline, gtk_buildinfo);
sfree(gtk_buildinfo);
}
}
#endif
#if defined _WINDOWS
{
int echm = has_embedded_chm();
if (echm >= 0)
strbuf_catf(buf, "%sEmbedded HTML Help file: %s", newline,
echm ? "yes" : "no");
}
#endif
#if defined _WINDOWS && defined MINEFIELD
strbuf_catf(buf, "%sBuild option: MINEFIELD", newline);
#endif
#ifdef NO_SECURITY
strbuf_catf(buf, "%sBuild option: NO_SECURITY", newline);
#endif
#ifdef NO_SECUREZEROMEMORY
strbuf_catf(buf, "%sBuild option: NO_SECUREZEROMEMORY", newline);
#endif
#ifdef NO_IPV6
strbuf_catf(buf, "%sBuild option: NO_IPV6", newline);
#endif
#ifdef NO_GSSAPI
strbuf_catf(buf, "%sBuild option: NO_GSSAPI", newline);
#endif
#ifdef STATIC_GSSAPI
strbuf_catf(buf, "%sBuild option: STATIC_GSSAPI", newline);
#endif
#ifdef UNPROTECT
strbuf_catf(buf, "%sBuild option: UNPROTECT", newline);
#endif
#ifdef FUZZING
strbuf_catf(buf, "%sBuild option: FUZZING", newline);
#endif
#ifdef DEBUG
strbuf_catf(buf, "%sBuild option: DEBUG", newline);
#endif
strbuf_catf(buf, "%sSource commit: %s", newline, commitid);
return strbuf_to_str(buf);
}
size_t nullseat_output(
Seat *seat, bool is_stderr, const void *data, size_t len) { return 0; }
bool nullseat_eof(Seat *seat) { return true; }
int nullseat_get_userpass_input(
Seat *seat, prompts_t *p, bufchain *input) { return 0; }
void nullseat_notify_remote_exit(Seat *seat) {}
void nullseat_connection_fatal(Seat *seat, const char *message) {}
void nullseat_update_specials_menu(Seat *seat) {}
char *nullseat_get_ttymode(Seat *seat, const char *mode) { return NULL; }
void nullseat_set_busy_status(Seat *seat, BusyStatus status) {}
int nullseat_verify_ssh_host_key(
Seat *seat, const char *host, int port,
const char *keytype, char *keystr, char *key_fingerprint,
void (*callback)(void *ctx, int result), void *ctx) { return 0; }
int nullseat_confirm_weak_crypto_primitive(
Seat *seat, const char *algtype, const char *algname,
void (*callback)(void *ctx, int result), void *ctx) { return 0; }
int nullseat_confirm_weak_cached_hostkey(
Seat *seat, const char *algname, const char *betteralgs,
void (*callback)(void *ctx, int result), void *ctx) { return 0; }
bool nullseat_is_never_utf8(Seat *seat) { return false; }
bool nullseat_is_always_utf8(Seat *seat) { return true; }
void nullseat_echoedit_update(Seat *seat, bool echoing, bool editing) {}
const char *nullseat_get_x_display(Seat *seat) { return NULL; }
bool nullseat_get_windowid(Seat *seat, long *id_out) { return false; }
bool nullseat_get_window_pixel_size(
Seat *seat, int *width, int *height) { return false; }
StripCtrlChars *nullseat_stripctrl_new(
Seat *seat, BinarySink *bs_out, SeatInteractionContext sic) {return NULL;}
bool nullseat_set_trust_status(Seat *seat, bool tr) { return false; }
bool nullseat_set_trust_status_vacuously(Seat *seat, bool tr) { return true; }
void sk_free_peer_info(SocketPeerInfo *pi)
{
if (pi) {
sfree((char *)pi->addr_text);
sfree((char *)pi->log_text);
sfree(pi);
}
}
void out_of_memory(void)
{
modalfatalbox("Out of memory");
}