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putty-source/cmdgen.c

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/*
* cmdgen.c - command-line form of PuTTYgen
*/
/*
* TODO:
*
* - Test thoroughly.
* + a neat way to do this might be to have a -DTESTMODE for
* this file, which #defines console_get_line and
* get_random_noise to different names in order to be able to
* link them to test stubs rather than the real ones. That
* way I can have a test rig which checks whether passphrases
* are being prompted for.
*/
#define PUTTY_DO_GLOBALS
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <limits.h>
#include <assert.h>
#include <time.h>
#include "putty.h"
#include "ssh.h"
#ifdef TESTMODE
#define get_random_data get_random_data_diagnostic
char *get_random_data(int len)
{
char *buf = snewn(len, char);
memset(buf, 'x', len);
return buf;
}
#endif
struct progress {
int phase, current;
};
static void progress_update(void *param, int action, int phase, int iprogress)
{
struct progress *p = (struct progress *)param;
if (action != PROGFN_PROGRESS)
return;
if (phase > p->phase) {
if (p->phase >= 0)
fputc('\n', stderr);
p->phase = phase;
if (iprogress >= 0)
p->current = iprogress - 1;
else
p->current = iprogress;
}
while (p->current < iprogress) {
fputc('+', stdout);
p->current++;
}
fflush(stdout);
}
static void no_progress(void *param, int action, int phase, int iprogress)
{
}
void modalfatalbox(char *p, ...)
{
va_list ap;
fprintf(stderr, "FATAL ERROR: ");
va_start(ap, p);
vfprintf(stderr, p, ap);
va_end(ap);
fputc('\n', stderr);
cleanup_exit(1);
}
/*
* Stubs to let everything else link sensibly.
*/
void log_eventlog(void *handle, const char *event)
{
}
char *x_get_default(const char *key)
{
return NULL;
}
void sk_cleanup(void)
{
}
void showversion(void)
{
char *verstr = dupstr(ver);
verstr[0] = tolower(verstr[0]);
printf("PuTTYgen %s\n", verstr);
sfree(verstr);
}
void usage(void)
{
fprintf(stderr,
"Usage: puttygen ( keyfile | -t type [ -b bits ] )\n"
" [ -C comment ] [ -P ]\n"
" [ -o output-keyfile ] [ -O type ]\n");
}
void help(void)
{
/*
* Help message is an extended version of the usage message. So
* start with that, plus a version heading.
*/
showversion();
usage();
fprintf(stderr,
" -t specify key type when generating (rsa, dsa, rsa1)\n"
" -C change or specify key comment\n"
" -P change key passphrase\n"
" -O specify output type:\n"
" private output PuTTY private key format\n"
" private-openssh export OpenSSH private key\n"
" private-sshcom export ssh.com private key\n"
" public standard / ssh.com public key\n"
" public-openssh OpenSSH public key\n"
" fingerprint output the key fingerprint\n"
" -l equivalent to `-O fingerprint'\n"
" -L equivalent to `-O public-openssh'\n"
" -p equivalent to `-O public'\n"
);
}
static int save_ssh2_pubkey(char *filename, char *comment,
void *v_pub_blob, int pub_len)
{
unsigned char *pub_blob = (unsigned char *)v_pub_blob;
char *p;
int i, column;
FILE *fp;
if (filename) {
fp = fopen(filename, "wb");
if (!fp)
return 0;
} else
fp = stdout;
fprintf(fp, "---- BEGIN SSH2 PUBLIC KEY ----\n");
if (comment) {
fprintf(fp, "Comment: \"");
for (p = comment; *p; p++) {
if (*p == '\\' || *p == '\"')
fputc('\\', fp);
fputc(*p, fp);
}
fprintf(fp, "\"\n");
}
i = 0;
column = 0;
while (i < pub_len) {
char buf[5];
int n = (pub_len - i < 3 ? pub_len - i : 3);
base64_encode_atom(pub_blob + i, n, buf);
i += n;
buf[4] = '\0';
fputs(buf, fp);
if (++column >= 16) {
fputc('\n', fp);
column = 0;
}
}
if (column > 0)
fputc('\n', fp);
fprintf(fp, "---- END SSH2 PUBLIC KEY ----\n");
if (filename)
fclose(fp);
return 1;
}
static void move(char *from, char *to)
{
int ret;
ret = rename(from, to);
if (ret) {
/*
* This OS may require us to remove the original file first.
*/
remove(to);
ret = rename(from, to);
}
if (ret) {
perror("puttygen: cannot move new file on to old one");
exit(1);
}
}
static char *blobfp(char *alg, int bits, char *blob, int bloblen)
{
char buffer[128];
unsigned char digest[16];
struct MD5Context md5c;
int i;
MD5Init(&md5c);
MD5Update(&md5c, blob, bloblen);
MD5Final(digest, &md5c);
sprintf(buffer, "%s ", alg);
if (bits > 0)
sprintf(buffer + strlen(buffer), "%d ", bits);
for (i = 0; i < 16; i++)
sprintf(buffer + strlen(buffer), "%s%02x", i ? ":" : "",
digest[i]);
return dupstr(buffer);
}
int main(int argc, char **argv)
{
char *infile = NULL;
Filename infilename;
enum { NOKEYGEN, RSA1, RSA2, DSA } keytype = NOKEYGEN;
char *outfile = NULL, *outfiletmp = NULL;
Filename outfilename;
enum { PRIVATE, PUBLIC, PUBLICO, FP, OPENSSH, SSHCOM } outtype = PRIVATE;
int bits = 1024;
char *comment = NULL, *origcomment = NULL;
int change_passphrase = FALSE;
int errs = FALSE, nogo = FALSE;
int intype = SSH_KEYTYPE_UNOPENABLE;
int sshver = 0;
struct ssh2_userkey *ssh2key = NULL;
struct RSAKey *ssh1key = NULL;
char *ssh2blob = NULL, *ssh2alg = NULL;
const struct ssh_signkey *ssh2algf = NULL;
int ssh2bloblen;
char *passphrase = NULL;
int load_encrypted;
progfn_t progressfn = is_interactive() ? progress_update : no_progress;
/* ------------------------------------------------------------------
* Parse the command line to figure out what we've been asked to do.
*/
/*
* If run with no arguments at all, print the usage message and
* return success.
*/
if (argc <= 1) {
usage();
return 0;
}
/*
* Parse command line arguments.
*/
while (--argc) {
char *p = *++argv;
if (*p == '-') {
/*
* An option.
*/
while (p && *++p) {
char c = *p;
switch (c) {
case '-':
/*
* Long option.
*/
{
char *opt, *val;
opt = p++; /* opt will have _one_ leading - */
while (*p && *p != '=')
p++; /* find end of option */
if (*p == '=') {
*p++ = '\0';
val = p;
} else
val = NULL;
if (!strcmp(opt, "-help")) {
help();
nogo = TRUE;
} else if (!strcmp(opt, "-version")) {
showversion();
nogo = TRUE;
}
/*
* A sample option requiring an argument:
*
* else if (!strcmp(opt, "-output")) {
* if (!val)
* errs = TRUE, error(err_optnoarg, opt);
* else
* ofile = val;
* }
*/
else {
errs = TRUE;
fprintf(stderr,
"puttygen: no such option `--%s'\n", opt);
}
}
p = NULL;
break;
case 'h':
case 'V':
case 'P':
case 'l':
case 'L':
case 'p':
case 'q':
/*
* Option requiring no parameter.
*/
switch (c) {
case 'h':
help();
nogo = TRUE;
break;
case 'V':
showversion();
nogo = TRUE;
break;
case 'P':
change_passphrase = TRUE;
break;
case 'l':
outtype = FP;
break;
case 'L':
outtype = PUBLICO;
break;
case 'p':
outtype = PUBLIC;
break;
case 'q':
progressfn = no_progress;
break;
}
break;
case 't':
case 'b':
case 'C':
case 'O':
case 'o':
/*
* Option requiring parameter.
*/
p++;
if (!*p && argc > 1)
--argc, p = *++argv;
else if (!*p) {
fprintf(stderr, "puttygen: option `-%c' expects a"
" parameter\n", c);
errs = TRUE;
}
/*
* Now c is the option and p is the parameter.
*/
switch (c) {
case 't':
if (!strcmp(p, "rsa") || !strcmp(p, "rsa2"))
keytype = RSA2, sshver = 2;
else if (!strcmp(p, "rsa1"))
keytype = RSA1, sshver = 1;
else if (!strcmp(p, "dsa") || !strcmp(p, "dss"))
keytype = DSA, sshver = 2;
else {
fprintf(stderr,
"puttygen: unknown key type `%s'\n", p);
errs = TRUE;
}
break;
case 'b':
bits = atoi(p);
break;
case 'C':
comment = p;
break;
case 'O':
if (!strcmp(p, "public"))
outtype = PUBLIC;
else if (!strcmp(p, "public-openssh"))
outtype = PUBLICO;
else if (!strcmp(p, "private"))
outtype = PRIVATE;
else if (!strcmp(p, "fingerprint"))
outtype = FP;
else if (!strcmp(p, "private-openssh"))
outtype = OPENSSH, sshver = 2;
else if (!strcmp(p, "private-sshcom"))
outtype = SSHCOM, sshver = 2;
else {
fprintf(stderr,
"puttygen: unknown output type `%s'\n", p);
errs = TRUE;
}
break;
case 'o':
outfile = p;
break;
}
p = NULL; /* prevent continued processing */
break;
default:
/*
* Unrecognised option.
*/
errs = TRUE;
fprintf(stderr, "puttygen: no such option `-%c'\n", c);
break;
}
}
} else {
/*
* A non-option argument.
*/
if (!infile)
infile = p;
else {
errs = TRUE;
fprintf(stderr, "puttygen: cannot handle more than one"
" input file\n");
}
}
}
if (errs)
return 1;
if (nogo)
return 0;
/*
* If run with at least one argument _but_ not the required
* ones, print the usage message and return failure.
*/
if (!infile && keytype == NOKEYGEN) {
usage();
return 1;
}
/* ------------------------------------------------------------------
* Figure out further details of exactly what we're going to do.
*/
/*
* Bomb out if we've been asked to both load and generate a
* key.
*/
if (keytype != NOKEYGEN && intype) {
fprintf(stderr, "puttygen: cannot both load and generate a key\n");
return 1;
}
/*
* Analyse the type of the input file, in case this affects our
* course of action.
*/
if (infile) {
infilename = filename_from_str(infile);
intype = key_type(&infilename);
switch (intype) {
/*
* It would be nice here to be able to load _public_
* key files, in any of a number of forms, and (a)
* convert them to other public key types, (b) print
* out their fingerprints. Or, I suppose, for real
* orthogonality, (c) change their comment!
*
* In fact this opens some interesting possibilities.
* Suppose ssh2_userkey_loadpub() were able to load
* public key files as well as extracting the public
* key from private ones. And suppose I did the thing
* I've been wanting to do, where specifying a
* particular private key file for authentication
* causes any _other_ key in the agent to be discarded.
* Then, if you had an agent forwarded to the machine
* you were running Unix PuTTY or Plink on, and you
* needed to specify which of the keys in the agent it
* should use, you could do that by supplying a
* _public_ key file, thus not needing to trust even
* your encrypted private key file to the network. Ooh!
*/
case SSH_KEYTYPE_UNOPENABLE:
case SSH_KEYTYPE_UNKNOWN:
fprintf(stderr, "puttygen: unable to load file `%s': %s\n",
infile, key_type_to_str(intype));
return 1;
case SSH_KEYTYPE_SSH1:
if (sshver == 2) {
fprintf(stderr, "puttygen: conversion from SSH1 to SSH2 keys"
" not supported\n");
return 1;
}
sshver = 1;
break;
case SSH_KEYTYPE_SSH2:
case SSH_KEYTYPE_OPENSSH:
case SSH_KEYTYPE_SSHCOM:
if (sshver == 1) {
fprintf(stderr, "puttygen: conversion from SSH2 to SSH1 keys"
" not supported\n");
return 1;
}
sshver = 2;
break;
}
}
/*
* Determine the default output file, if none is provided.
*
* This will usually be equal to stdout, except that if the
* input and output file formats are the same then the default
* output is to overwrite the input.
*
* Also in this code, we bomb out if the input and output file
* formats are the same and no other action is performed.
*/
if ((intype == SSH_KEYTYPE_SSH1 && outtype == PRIVATE) ||
(intype == SSH_KEYTYPE_SSH2 && outtype == PRIVATE) ||
(intype == SSH_KEYTYPE_OPENSSH && outtype == OPENSSH) ||
(intype == SSH_KEYTYPE_SSHCOM && outtype == SSHCOM)) {
if (!outfile) {
outfile = infile;
outfiletmp = dupcat(outfile, ".tmp");
}
if (!change_passphrase && !comment) {
fprintf(stderr, "puttygen: this command would perform no useful"
" action\n");
return 1;
}
} else {
if (!outfile) {
/*
* Bomb out rather than automatically choosing to write
* a private key file to stdout.
*/
if (outtype==PRIVATE || outtype==OPENSSH || outtype==SSHCOM) {
fprintf(stderr, "puttygen: need to specify an output file\n");
return 1;
}
}
}
/*
* Figure out whether we need to load the encrypted part of the
* key. This will be the case if either (a) we need to write
* out a private key format, or (b) the entire input key file
* is encrypted.
*/
if (outtype == PRIVATE || outtype == OPENSSH || outtype == SSHCOM ||
intype == SSH_KEYTYPE_OPENSSH || intype == SSH_KEYTYPE_SSHCOM)
load_encrypted = TRUE;
else
load_encrypted = FALSE;
/* ------------------------------------------------------------------
* Now we're ready to actually do some stuff.
*/
/*
* Either load or generate a key.
*/
if (keytype != NOKEYGEN) {
char *entropy;
char default_comment[80];
time_t t;
struct tm *tm;
struct progress prog;
prog.phase = -1;
prog.current = -1;
time(&t);
tm = localtime(&t);
if (keytype == DSA)
strftime(default_comment, 30, "dsa-key-%Y%m%d", tm);
else
strftime(default_comment, 30, "rsa-key-%Y%m%d", tm);
random_init();
entropy = get_random_data(bits / 8);
random_add_heavynoise(entropy, bits / 8);
memset(entropy, 0, bits/8);
sfree(entropy);
if (keytype == DSA) {
struct dss_key *dsskey = snew(struct dss_key);
dsa_generate(dsskey, bits, progressfn, &prog);
ssh2key = snew(struct ssh2_userkey);
ssh2key->data = dsskey;
ssh2key->alg = &ssh_dss;
ssh1key = NULL;
} else {
struct RSAKey *rsakey = snew(struct RSAKey);
rsa_generate(rsakey, bits, progressfn, &prog);
if (keytype == RSA1) {
ssh1key = rsakey;
} else {
ssh2key = snew(struct ssh2_userkey);
ssh2key->data = rsakey;
ssh2key->alg = &ssh_rsa;
}
}
progressfn(&prog, PROGFN_PROGRESS, INT_MAX, -1);
if (ssh2key)
ssh2key->comment = dupstr(default_comment);
if (ssh1key)
ssh1key->comment = dupstr(default_comment);
} else {
const char *error = NULL;
int encrypted;
assert(infile != NULL);
/*
* Find out whether the input key is encrypted.
*/
if (intype == SSH_KEYTYPE_SSH1)
encrypted = rsakey_encrypted(&infilename, &origcomment);
else if (intype == SSH_KEYTYPE_SSH2)
encrypted = ssh2_userkey_encrypted(&infilename, &origcomment);
else
encrypted = import_encrypted(&infilename, intype, &origcomment);
/*
* If so, ask for a passphrase.
*/
if (encrypted && load_encrypted) {
passphrase = snewn(512, char);
if (!console_get_line("Enter passphrase to load key: ",
passphrase, 512, TRUE)) {
perror("puttygen: unable to read passphrase");
return 1;
}
} else {
passphrase = NULL;
}
switch (intype) {
int ret;
case SSH_KEYTYPE_SSH1:
ssh1key = snew(struct RSAKey);
if (!load_encrypted) {
void *vblob;
char *blob;
int n, bloblen;
ret = rsakey_pubblob(&infilename, &vblob, &bloblen, &error);
blob = (char *)vblob;
n = 4; /* skip modulus bits */
n += ssh1_read_bignum(blob + n, &ssh1key->exponent);
n += ssh1_read_bignum(blob + n, &ssh1key->modulus);
ssh1key->comment = NULL;
} else {
ret = loadrsakey(&infilename, ssh1key, passphrase, &error);
}
if (ret)
error = NULL;
else if (!error)
error = "unknown error";
break;
case SSH_KEYTYPE_SSH2:
if (!load_encrypted) {
ssh2blob = ssh2_userkey_loadpub(&infilename, &ssh2alg,
&ssh2bloblen, &error);
ssh2algf = find_pubkey_alg(ssh2alg);
if (ssh2algf)
bits = ssh2algf->pubkey_bits(ssh2blob, ssh2bloblen);
else
bits = -1;
} else {
ssh2key = ssh2_load_userkey(&infilename, passphrase, &error);
}
if (ssh2key || ssh2blob)
error = NULL;
else if (!error) {
if (ssh2key == SSH2_WRONG_PASSPHRASE)
error = "wrong passphrase";
else
error = "unknown error";
}
break;
case SSH_KEYTYPE_OPENSSH:
case SSH_KEYTYPE_SSHCOM:
ssh2key = import_ssh2(&infilename, intype, passphrase);
if (ssh2key)
error = NULL;
else if (!error) {
if (ssh2key == SSH2_WRONG_PASSPHRASE)
error = "wrong passphrase";
else
error = "unknown error";
}
break;
default:
assert(0);
}
if (error) {
fprintf(stderr, "puttygen: error loading `%s': %s\n",
infile, error);
return 1;
}
}
/*
* Change the comment if asked to.
*/
if (comment) {
if (sshver == 1) {
assert(ssh1key);
sfree(ssh1key->comment);
ssh1key->comment = dupstr(comment);
} else {
assert(ssh2key);
sfree(ssh2key->comment);
ssh2key->comment = dupstr(comment);
}
}
/*
* Prompt for a new passphrase if we have been asked to, or if
* we have just generated a key.
*/
if (change_passphrase || keytype != NOKEYGEN) {
char *passphrase2;
if (passphrase) {
memset(passphrase, 0, strlen(passphrase));
sfree(passphrase);
}
passphrase = snewn(512, char);
passphrase2 = snewn(512, char);
if (!console_get_line("Enter passphrase to save key: ",
passphrase, 512, TRUE) ||
!console_get_line("Re-enter passphrase to verify: ",
passphrase2, 512, TRUE)) {
perror("puttygen: unable to read new passphrase");
return 1;
}
if (strcmp(passphrase, passphrase2)) {
fprintf(stderr, "puttygen: passphrases do not match\n");
return 1;
}
memset(passphrase2, 0, strlen(passphrase2));
sfree(passphrase2);
if (!*passphrase) {
sfree(passphrase);
passphrase = NULL;
}
}
/*
* Write output.
*
* (In the case where outfile and outfiletmp are both NULL,
* there is no semantic reason to initialise outfilename at
* all; but we have to write _something_ to it or some compiler
* will probably complain that it might be used uninitialised.)
*/
if (outfiletmp)
outfilename = filename_from_str(outfiletmp);
else
outfilename = filename_from_str(outfile ? outfile : "");
switch (outtype) {
int ret;
case PRIVATE:
if (sshver == 1) {
assert(ssh1key);
ret = saversakey(&outfilename, ssh1key, passphrase);
if (!ret) {
fprintf(stderr, "puttygen: unable to save SSH1 private key\n");
return 1;
}
} else {
assert(ssh2key);
ret = ssh2_save_userkey(&outfilename, ssh2key, passphrase);
if (!ret) {
fprintf(stderr, "puttygen: unable to save SSH2 private key\n");
return 1;
}
}
if (outfiletmp)
move(outfiletmp, outfile);
break;
case PUBLIC:
case PUBLICO:
if (sshver == 1) {
FILE *fp;
char *dec1, *dec2;
assert(ssh1key);
if (outfile)
fp = f_open(outfilename, "w");
else
fp = stdout;
dec1 = bignum_decimal(ssh1key->exponent);
dec2 = bignum_decimal(ssh1key->modulus);
fprintf(fp, "%d %s %s %s\n", bignum_bitcount(ssh1key->modulus),
dec1, dec2, ssh1key->comment);
sfree(dec1);
sfree(dec2);
if (outfile)
fclose(fp);
} else if (outtype == PUBLIC) {
if (!ssh2blob) {
assert(ssh2key);
ssh2blob = ssh2key->alg->public_blob(ssh2key->data,
&ssh2bloblen);
}
save_ssh2_pubkey(outfile, ssh2key ? ssh2key->comment : origcomment,
ssh2blob, ssh2bloblen);
} else if (outtype == PUBLICO) {
char *buffer, *p;
int i;
FILE *fp;
if (!ssh2blob) {
assert(ssh2key);
ssh2blob = ssh2key->alg->public_blob(ssh2key->data,
&ssh2bloblen);
}
if (!ssh2alg) {
assert(ssh2key);
ssh2alg = ssh2key->alg->name;
}
if (ssh2key)
comment = ssh2key->comment;
else
comment = origcomment;
buffer = snewn(strlen(ssh2alg) +
4 * ((ssh2bloblen+2) / 3) +
strlen(comment) + 3, char);
strcpy(buffer, ssh2alg);
p = buffer + strlen(buffer);
*p++ = ' ';
i = 0;
while (i < ssh2bloblen) {
int n = (ssh2bloblen - i < 3 ? ssh2bloblen - i : 3);
base64_encode_atom(ssh2blob + i, n, p);
i += n;
p += 4;
}
if (*comment) {
*p++ = ' ';
strcpy(p, comment);
} else
*p++ = '\0';
if (outfile)
fp = f_open(outfilename, "w");
else
fp = stdout;
fprintf(fp, "%s\n", buffer);
if (outfile)
fclose(fp);
sfree(buffer);
}
break;
case FP:
{
FILE *fp;
char *fingerprint;
if (sshver == 1) {
assert(ssh1key);
fingerprint = snewn(128, char);
rsa_fingerprint(fingerprint, 128, ssh1key);
} else {
if (ssh2key) {
fingerprint = ssh2key->alg->fingerprint(ssh2key->data);
} else {
assert(ssh2blob);
fingerprint = blobfp(ssh2alg, bits, ssh2blob, ssh2bloblen);
}
}
if (outfile)
fp = f_open(outfilename, "w");
else
fp = stdout;
fprintf(fp, "%s\n", fingerprint);
if (outfile)
fclose(fp);
sfree(fingerprint);
}
break;
case OPENSSH:
case SSHCOM:
assert(sshver == 2);
assert(ssh2key);
ret = export_ssh2(&outfilename, outtype, ssh2key, passphrase);
if (!ret) {
fprintf(stderr, "puttygen: unable to export key\n");
return 1;
}
if (outfiletmp)
move(outfiletmp, outfile);
break;
}
if (passphrase) {
memset(passphrase, 0, strlen(passphrase));
sfree(passphrase);
}
if (ssh1key)
freersakey(ssh1key);
if (ssh2key) {
ssh2key->alg->freekey(ssh2key->data);
sfree(ssh2key);
}
return 0;
}