" private-openssh-new export OpenSSH private key "
"(force new file format)\n"
" private-sshcom export ssh.com private key\n"
- " public standard / ssh.com public key\n"
+ " public RFC 4716 / ssh.com public key\n"
" public-openssh OpenSSH public key\n"
" fingerprint output the key fingerprint\n"
" -o specify output file\n"
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",
return 1;
case SSH_KEYTYPE_SSH1:
+ case SSH_KEYTYPE_SSH1_PUBLIC:
if (sshver == 2) {
fprintf(stderr, "puttygen: conversion from SSH-1 to SSH-2 keys"
" not supported\n");
break;
case SSH_KEYTYPE_SSH2:
+ case SSH_KEYTYPE_SSH2_PUBLIC_RFC4716:
+ case SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH:
case SSH_KEYTYPE_OPENSSH_PEM:
case SSH_KEYTYPE_OPENSSH_NEW:
case SSH_KEYTYPE_SSHCOM:
else
load_encrypted = FALSE;
+ if (load_encrypted && (intype == SSH_KEYTYPE_SSH1_PUBLIC ||
+ intype == SSH_KEYTYPE_SSH2_PUBLIC_RFC4716 ||
+ intype == SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH)) {
+ fprintf(stderr, "puttygen: cannot perform this action on a "
+ "public-key-only input file\n");
+ return 1;
+ }
+
/* ------------------------------------------------------------------
* Now we're ready to actually do some stuff.
*/
int ret;
case SSH_KEYTYPE_SSH1:
+ case SSH_KEYTYPE_SSH1_PUBLIC:
ssh1key = snew(struct RSAKey);
if (!load_encrypted) {
void *vblob;
break;
case SSH_KEYTYPE_SSH2:
+ case SSH_KEYTYPE_SSH2_PUBLIC_RFC4716:
+ case SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH:
if (!load_encrypted) {
ssh2blob = ssh2_userkey_loadpub(infilename, &ssh2alg,
- &ssh2bloblen, NULL, &error);
+ &ssh2bloblen, &origcomment,
+ &error);
if (ssh2blob) {
ssh2algf = find_pubkey_alg(ssh2alg);
if (ssh2algf)
(x)=='+' ? 62 : \
(x)=='/' ? 63 : 0 )
+static int key_type_fp(FILE *fp);
+
static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only,
char **commentptr, const char *passphrase,
const char **error)
}
fp = NULL; /* loadrsakey_main unconditionally closes fp */
} else {
+ /*
+ * Try interpreting the file as an SSH-1 public key.
+ */
+ char *line, *p, *bitsp, *expp, *modp, *commentp;
+
+ rewind(fp);
+ line = chomp(fgetline(fp));
+ p = line;
+
+ bitsp = p;
+ p += strspn(p, "0123456789");
+ if (*p != ' ')
+ goto not_public_either;
+ *p++ = '\0';
+
+ expp = p;
+ p += strspn(p, "0123456789");
+ if (*p != ' ')
+ goto not_public_either;
+ *p++ = '\0';
+
+ modp = p;
+ p += strspn(p, "0123456789");
+ if (*p) {
+ if (*p != ' ')
+ goto not_public_either;
+ *p++ = '\0';
+ commentp = p;
+ } else {
+ commentp = NULL;
+ }
+
+ memset(&key, 0, sizeof(key));
+ key.exponent = bignum_from_decimal(expp);
+ key.modulus = bignum_from_decimal(modp);
+ if (atoi(bitsp) != bignum_bitcount(key.modulus)) {
+ freebn(key.exponent);
+ freebn(key.modulus);
+ sfree(line);
+ error = "key bit count does not match in SSH-1 public key file";
+ goto end;
+ }
+ if (commentptr)
+ *commentptr = commentp ? dupstr(commentp) : NULL;
+ *blob = rsa_public_blob(&key, bloblen);
+ freersakey(&key);
+ return 1;
+
+ not_public_either:
+ sfree(line);
error = "not an SSH-1 RSA file";
}
return ret;
}
+unsigned char *rfc4716_loadpub(FILE *fp, char **algorithm,
+ int *pub_blob_len, char **commentptr,
+ const char **errorstr)
+{
+ const char *error;
+ char *line, *colon, *value;
+ char *comment = NULL;
+ unsigned char *pubblob = NULL;
+ int pubbloblen, pubblobsize;
+ char base64in[4];
+ unsigned char base64out[3];
+ int base64bytes;
+ int alglen;
+
+ line = chomp(fgetline(fp));
+ if (!line || 0 != strcmp(line, "---- BEGIN SSH2 PUBLIC KEY ----")) {
+ error = "invalid begin line in SSH-2 public key file";
+ goto error;
+ }
+ sfree(line); line = NULL;
+
+ while (1) {
+ line = chomp(fgetline(fp));
+ if (!line) {
+ error = "truncated SSH-2 public key file";
+ goto error;
+ }
+ colon = strstr(line, ": ");
+ if (!colon)
+ break;
+ *colon = '\0';
+ value = colon + 2;
+
+ if (!strcmp(line, "Comment")) {
+ char *p, *q;
+
+ /* Remove containing double quotes, if present */
+ p = value;
+ if (*p == '"' && p[strlen(p)-1] == '"') {
+ p[strlen(p)-1] = '\0';
+ p++;
+ }
+
+ /* Remove \-escaping, not in RFC4716 but seen in the wild
+ * in practice. */
+ for (q = line; *p; p++) {
+ if (*p == '\\' && p[1])
+ p++;
+ *q++ = *p;
+ }
+
+ *q = '\0';
+ comment = dupstr(line);
+ } else if (!strcmp(line, "Subject") ||
+ !strncmp(line, "x-", 2)) {
+ /* Headers we recognise and ignore. Do nothing. */
+ } else {
+ error = "unrecognised header in SSH-2 public key file";
+ goto error;
+ }
+
+ sfree(line); line = NULL;
+ }
+
+ /*
+ * Now line contains the initial line of base64 data. Loop round
+ * while it still does contain base64.
+ */
+ pubblobsize = 4096;
+ pubblob = snewn(pubblobsize, unsigned char);
+ pubbloblen = 0;
+ base64bytes = 0;
+ while (line && line[0] != '-') {
+ char *p;
+ for (p = line; *p; p++) {
+ base64in[base64bytes++] = *p;
+ if (base64bytes == 4) {
+ int n = base64_decode_atom(base64in, base64out);
+ if (pubbloblen + n > pubblobsize) {
+ pubblobsize = (pubbloblen + n) * 5 / 4 + 1024;
+ pubblob = sresize(pubblob, pubblobsize, unsigned char);
+ }
+ memcpy(pubblob + pubbloblen, base64out, n);
+ pubbloblen += n;
+ base64bytes = 0;
+ }
+ }
+ sfree(line); line = NULL;
+ line = chomp(fgetline(fp));
+ }
+
+ /*
+ * Finally, check the END line makes sense.
+ */
+ if (!line || 0 != strcmp(line, "---- END SSH2 PUBLIC KEY ----")) {
+ error = "invalid end line in SSH-2 public key file";
+ goto error;
+ }
+ sfree(line); line = NULL;
+
+ /*
+ * OK, we now have a public blob and optionally a comment. We must
+ * return the key algorithm string too, so look for that at the
+ * start of the public blob.
+ */
+ if (pubbloblen < 4) {
+ error = "not enough data in SSH-2 public key file";
+ goto error;
+ }
+ alglen = toint(GET_32BIT(pubblob));
+ if (alglen < 0 || alglen > pubbloblen-4) {
+ error = "invalid algorithm prefix in SSH-2 public key file";
+ goto error;
+ }
+ if (algorithm)
+ *algorithm = dupprintf("%.*s", alglen, pubblob+4);
+ if (pub_blob_len)
+ *pub_blob_len = pubbloblen;
+ if (commentptr)
+ *commentptr = comment;
+ else
+ sfree(comment);
+ return pubblob;
+
+ error:
+ sfree(line);
+ sfree(comment);
+ sfree(pubblob);
+ if (errorstr)
+ *errorstr = error;
+ return NULL;
+}
+
+unsigned char *openssh_loadpub(FILE *fp, char **algorithm,
+ int *pub_blob_len, char **commentptr,
+ const char **errorstr)
+{
+ const char *error;
+ char *line, *base64;
+ char *comment = NULL;
+ unsigned char *pubblob = NULL;
+ int pubbloblen, pubblobsize;
+ int alglen;
+
+ line = chomp(fgetline(fp));
+
+ base64 = strchr(line, ' ');
+ if (!base64) {
+ error = "no key blob in OpenSSH public key file";
+ goto error;
+ }
+ *base64++ = '\0';
+
+ comment = strchr(base64, ' ');
+ if (comment) {
+ *comment++ = '\0';
+ comment = dupstr(comment);
+ }
+
+ pubblobsize = strlen(base64) / 4 * 3;
+ pubblob = snewn(pubblobsize, unsigned char);
+ pubbloblen = 0;
+
+ while (!memchr(base64, '\0', 4)) {
+ assert(pubbloblen + 3 <= pubblobsize);
+ pubbloblen += base64_decode_atom(base64, pubblob + pubbloblen);
+ base64 += 4;
+ }
+ if (*base64) {
+ error = "invalid length for base64 data in OpenSSH public key file";
+ goto error;
+ }
+
+ /*
+ * Sanity check: the first word on the line should be the key
+ * algorithm, and should match the encoded string at the start of
+ * the public blob.
+ */
+ alglen = strlen(line);
+ if (pubbloblen < alglen + 4 ||
+ GET_32BIT(pubblob) != alglen ||
+ 0 != memcmp(pubblob + 4, line, alglen)) {
+ error = "key algorithms do not match in OpenSSH public key file";
+ goto error;
+ }
+
+ /*
+ * Done.
+ */
+ if (algorithm)
+ *algorithm = dupstr(line);
+ if (pub_blob_len)
+ *pub_blob_len = pubbloblen;
+ if (commentptr)
+ *commentptr = comment;
+ else
+ sfree(comment);
+ return pubblob;
+
+ error:
+ sfree(line);
+ sfree(comment);
+ sfree(pubblob);
+ if (errorstr)
+ *errorstr = error;
+ return NULL;
+}
+
unsigned char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
int *pub_blob_len, char **commentptr,
const char **errorstr)
const struct ssh_signkey *alg;
unsigned char *public_blob;
int public_blob_len;
- int i;
+ int type, i;
const char *error = NULL;
char *comment = NULL;
goto error;
}
+ /* Initially, check if this is a public-only key file. Sometimes
+ * we'll be asked to read a public blob from one of those. */
+ type = key_type_fp(fp);
+ if (type == SSH_KEYTYPE_SSH2_PUBLIC_RFC4716) {
+ unsigned char *ret = rfc4716_loadpub(fp, algorithm, pub_blob_len,
+ commentptr, errorstr);
+ fclose(fp);
+ return ret;
+ } else if (type == SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH) {
+ unsigned char *ret = openssh_loadpub(fp, algorithm, pub_blob_len,
+ commentptr, errorstr);
+ fclose(fp);
+ return ret;
+ } else if (type != SSH_KEYTYPE_SSH2) {
+ error = "not a PuTTY SSH-2 private key";
+ goto error;
+ }
+
/* Read the first header line which contains the key type. */
if (!read_header(fp, header)
|| (0 != strcmp(header, "PuTTY-User-Key-File-2") &&
}
/* ----------------------------------------------------------------------
- * A function to determine the type of a private key file. Returns
- * 0 on failure, 1 or 2 on success.
+ * Determine the type of a private key file.
*/
-int key_type(const Filename *filename)
+static int key_type_fp(FILE *fp)
{
- FILE *fp;
- char buf[32];
+ char buf[1024];
+ const char public_std_sig[] = "---- BEGIN SSH2 PUBLIC KEY";
const char putty2_sig[] = "PuTTY-User-Key-File-";
const char sshcom_sig[] = "---- BEGIN SSH2 ENCRYPTED PRIVAT";
const char openssh_new_sig[] = "-----BEGIN OPENSSH PRIVATE KEY";
const char openssh_sig[] = "-----BEGIN ";
int i;
+ char *p;
+
+ i = fread(buf, 1, sizeof(buf)-1, fp);
+ rewind(fp);
- fp = f_open(filename, "r", FALSE);
- if (!fp)
- return SSH_KEYTYPE_UNOPENABLE;
- i = fread(buf, 1, sizeof(buf), fp);
- fclose(fp);
if (i < 0)
return SSH_KEYTYPE_UNOPENABLE;
if (i < 32)
return SSH_KEYTYPE_UNKNOWN;
+ assert(i > 0 && i < sizeof(buf));
+ buf[i] = '\0';
if (!memcmp(buf, rsa_signature, sizeof(rsa_signature)-1))
return SSH_KEYTYPE_SSH1;
+ if (!memcmp(buf, public_std_sig, sizeof(public_std_sig)-1))
+ return SSH_KEYTYPE_SSH2_PUBLIC_RFC4716;
if (!memcmp(buf, putty2_sig, sizeof(putty2_sig)-1))
return SSH_KEYTYPE_SSH2;
if (!memcmp(buf, openssh_new_sig, sizeof(openssh_new_sig)-1))
return SSH_KEYTYPE_OPENSSH_PEM;
if (!memcmp(buf, sshcom_sig, sizeof(sshcom_sig)-1))
return SSH_KEYTYPE_SSHCOM;
+ if ((p = buf + strspn(buf, "0123456789"), *p == ' ') &&
+ (p = p+1 + strspn(p+1, "0123456789"), *p == ' ') &&
+ (p = p+1 + strspn(p+1, "0123456789"), *p == ' ' || *p == '\n' || !*p))
+ return SSH_KEYTYPE_SSH1_PUBLIC;
+ if ((p = buf + strcspn(buf, " "), find_pubkey_alg_len(p-buf, buf)) &&
+ (p = p+1 + strspn(p+1, "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghij"
+ "klmnopqrstuvwxyz+/="),
+ *p == ' ' || *p == '\n' || !*p))
+ return SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH;
return SSH_KEYTYPE_UNKNOWN; /* unrecognised or EOF */
}
+int key_type(const Filename *filename)
+{
+ FILE *fp;
+ int ret;
+
+ fp = f_open(filename, "r", FALSE);
+ if (!fp)
+ return SSH_KEYTYPE_UNOPENABLE;
+ ret = key_type_fp(fp);
+ fclose(fp);
+ return ret;
+}
+
/*
* Convert the type word to a string, for `wrong type' error
* messages.
{
switch (type) {
case SSH_KEYTYPE_UNOPENABLE: return "unable to open file"; break;
- case SSH_KEYTYPE_UNKNOWN: return "not a private key"; break;
+ case SSH_KEYTYPE_UNKNOWN: return "not a recognised key file format"; break;
+ case SSH_KEYTYPE_SSH1_PUBLIC: return "SSH-1 public key"; break;
+ case SSH_KEYTYPE_SSH2_PUBLIC_RFC4716: return "SSH-2 public key (RFC 4716 format)"; break;
+ case SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH: return "SSH-2 public key (OpenSSH format)"; break;
case SSH_KEYTYPE_SSH1: return "SSH-1 private key"; break;
case SSH_KEYTYPE_SSH2: return "PuTTY SSH-2 private key"; break;
case SSH_KEYTYPE_OPENSSH_PEM: return "OpenSSH SSH-2 private key (old PEM format)"; break;