2 * Generic SSH public-key handling operations. In particular,
3 * reading of SSH public-key files, and also the generic `sign'
4 * operation for SSH-2 (which checks the type of the key and
5 * dispatches to the appropriate key-type specific function).
16 #define rsa_signature "SSH PRIVATE KEY FILE FORMAT 1.1\n"
18 #define BASE64_TOINT(x) ( (x)-'A'<26 ? (x)-'A'+0 :\
19 (x)-'a'<26 ? (x)-'a'+26 :\
20 (x)-'0'<10 ? (x)-'0'+52 :\
24 static int loadrsakey_main(FILE * fp
, struct RSAKey
*key
, int pub_only
,
25 char **commentptr
, char *passphrase
,
28 unsigned char buf
[16384];
29 unsigned char keybuf
[16];
33 struct MD5Context md5c
;
38 /* Slurp the whole file (minus the header) into a buffer. */
39 len
= fread(buf
, 1, sizeof(buf
), fp
);
41 if (len
< 0 || len
== sizeof(buf
)) {
42 *error
= "error reading file";
43 goto end
; /* file too big or not read */
47 *error
= "file format error";
50 * A zero byte. (The signature includes a terminating NUL.)
52 if (len
- i
< 1 || buf
[i
] != 0)
56 /* One byte giving encryption type, and one reserved uint32. */
60 if (ciphertype
!= 0 && ciphertype
!= SSH_CIPHER_3DES
)
64 goto end
; /* reserved field not present */
65 if (buf
[i
] != 0 || buf
[i
+ 1] != 0 || buf
[i
+ 2] != 0
66 || buf
[i
+ 3] != 0) goto end
; /* reserved field nonzero, panic! */
69 /* Now the serious stuff. An ordinary SSH-1 public key. */
70 i
+= makekey(buf
+ i
, len
, key
, NULL
, 1);
72 goto end
; /* overran */
74 /* Next, the comment field. */
75 j
= GET_32BIT(buf
+ i
);
79 comment
= snewn(j
+ 1, char);
81 memcpy(comment
, buf
+ i
, j
);
86 *commentptr
= dupstr(comment
);
88 key
->comment
= comment
;
98 ret
= ciphertype
!= 0;
104 * Decrypt remainder of buffer.
108 MD5Update(&md5c
, (unsigned char *)passphrase
, strlen(passphrase
));
109 MD5Final(keybuf
, &md5c
);
110 des3_decrypt_pubkey(keybuf
, buf
+ i
, (len
- i
+ 7) & ~7);
111 memset(keybuf
, 0, sizeof(keybuf
)); /* burn the evidence */
115 * We are now in the secret part of the key. The first four
116 * bytes should be of the form a, b, a, b.
120 if (buf
[i
] != buf
[i
+ 2] || buf
[i
+ 1] != buf
[i
+ 3]) {
121 *error
= "wrong passphrase";
128 * After that, we have one further bignum which is our
129 * decryption exponent, and then the three auxiliary values
132 j
= makeprivate(buf
+ i
, len
- i
, key
);
135 j
= ssh1_read_bignum(buf
+ i
, len
- i
, &key
->iqmp
);
138 j
= ssh1_read_bignum(buf
+ i
, len
- i
, &key
->q
);
141 j
= ssh1_read_bignum(buf
+ i
, len
- i
, &key
->p
);
145 if (!rsa_verify(key
)) {
146 *error
= "rsa_verify failed";
153 memset(buf
, 0, sizeof(buf
)); /* burn the evidence */
157 int loadrsakey(const Filename
*filename
, struct RSAKey
*key
, char *passphrase
,
158 const char **errorstr
)
163 const char *error
= NULL
;
165 fp
= f_open(*filename
, "rb");
167 error
= "can't open file";
172 * Read the first line of the file and see if it's a v1 private
175 if (fgets(buf
, sizeof(buf
), fp
) && !strcmp(buf
, rsa_signature
)) {
177 * This routine will take care of calling fclose() for us.
179 ret
= loadrsakey_main(fp
, key
, FALSE
, NULL
, passphrase
, &error
);
185 * Otherwise, we have nothing. Return empty-handed.
187 error
= "not an SSH-1 RSA file";
192 if ((ret
!= 1) && errorstr
)
198 * See whether an RSA key is encrypted. Return its comment field as
201 int rsakey_encrypted(const Filename
*filename
, char **comment
)
206 fp
= f_open(*filename
, "rb");
208 return 0; /* doesn't even exist */
211 * Read the first line of the file and see if it's a v1 private
214 if (fgets(buf
, sizeof(buf
), fp
) && !strcmp(buf
, rsa_signature
)) {
217 * This routine will take care of calling fclose() for us.
219 return loadrsakey_main(fp
, NULL
, FALSE
, comment
, NULL
, &dummy
);
222 return 0; /* wasn't the right kind of file */
226 * Return a malloc'ed chunk of memory containing the public blob of
227 * an RSA key, as given in the agent protocol (modulus bits,
228 * exponent, modulus).
230 int rsakey_pubblob(const Filename
*filename
, void **blob
, int *bloblen
,
231 char **commentptr
, const char **errorstr
)
237 const char *error
= NULL
;
239 /* Default return if we fail. */
244 fp
= f_open(*filename
, "rb");
246 error
= "can't open file";
251 * Read the first line of the file and see if it's a v1 private
254 if (fgets(buf
, sizeof(buf
), fp
) && !strcmp(buf
, rsa_signature
)) {
255 memset(&key
, 0, sizeof(key
));
256 if (loadrsakey_main(fp
, &key
, TRUE
, commentptr
, NULL
, &error
)) {
257 *blob
= rsa_public_blob(&key
, bloblen
);
263 error
= "not an SSH-1 RSA file";
269 if ((ret
!= 1) && errorstr
)
275 * Save an RSA key file. Return nonzero on success.
277 int saversakey(const Filename
*filename
, struct RSAKey
*key
, char *passphrase
)
279 unsigned char buf
[16384];
280 unsigned char keybuf
[16];
281 struct MD5Context md5c
;
282 unsigned char *p
, *estart
;
286 * Write the initial signature.
289 memcpy(p
, rsa_signature
, sizeof(rsa_signature
));
290 p
+= sizeof(rsa_signature
);
293 * One byte giving encryption type, and one reserved (zero)
296 *p
++ = (passphrase ? SSH_CIPHER_3DES
: 0);
301 * An ordinary SSH-1 public key consists of: a uint32
302 * containing the bit count, then two bignums containing the
303 * modulus and exponent respectively.
305 PUT_32BIT(p
, bignum_bitcount(key
->modulus
));
307 p
+= ssh1_write_bignum(p
, key
->modulus
);
308 p
+= ssh1_write_bignum(p
, key
->exponent
);
311 * A string containing the comment field.
314 PUT_32BIT(p
, strlen(key
->comment
));
316 memcpy(p
, key
->comment
, strlen(key
->comment
));
317 p
+= strlen(key
->comment
);
324 * The encrypted portion starts here.
329 * Two bytes, then the same two bytes repeated.
331 *p
++ = random_byte();
332 *p
++ = random_byte();
338 * Four more bignums: the decryption exponent, then iqmp, then
341 p
+= ssh1_write_bignum(p
, key
->private_exponent
);
342 p
+= ssh1_write_bignum(p
, key
->iqmp
);
343 p
+= ssh1_write_bignum(p
, key
->q
);
344 p
+= ssh1_write_bignum(p
, key
->p
);
347 * Now write zeros until the encrypted portion is a multiple of
350 while ((p
- estart
) % 8)
354 * Now encrypt the encrypted portion.
358 MD5Update(&md5c
, (unsigned char *)passphrase
, strlen(passphrase
));
359 MD5Final(keybuf
, &md5c
);
360 des3_encrypt_pubkey(keybuf
, estart
, p
- estart
);
361 memset(keybuf
, 0, sizeof(keybuf
)); /* burn the evidence */
365 * Done. Write the result to the file.
367 fp
= f_open(*filename
, "wb");
369 int ret
= (fwrite(buf
, 1, p
- buf
, fp
) == (size_t) (p
- buf
));
377 /* ----------------------------------------------------------------------
378 * SSH-2 private key load/store functions.
382 * PuTTY's own format for SSH-2 keys is as follows:
384 * The file is text. Lines are terminated by CRLF, although CR-only
385 * and LF-only are tolerated on input.
387 * The first line says "PuTTY-User-Key-File-2: " plus the name of the
388 * algorithm ("ssh-dss", "ssh-rsa" etc).
390 * The next line says "Encryption: " plus an encryption type.
391 * Currently the only supported encryption types are "aes256-cbc"
394 * The next line says "Comment: " plus the comment string.
396 * Next there is a line saying "Public-Lines: " plus a number N.
397 * The following N lines contain a base64 encoding of the public
398 * part of the key. This is encoded as the standard SSH-2 public key
399 * blob (with no initial length): so for RSA, for example, it will
406 * Next, there is a line saying "Private-Lines: " plus a number N,
407 * and then N lines containing the (potentially encrypted) private
408 * part of the key. For the key type "ssh-rsa", this will be
411 * mpint private_exponent
412 * mpint p (the larger of the two primes)
413 * mpint q (the smaller prime)
414 * mpint iqmp (the inverse of q modulo p)
415 * data padding (to reach a multiple of the cipher block size)
417 * And for "ssh-dss", it will be composed of
419 * mpint x (the private key parameter)
420 * [ string hash 20-byte hash of mpints p || q || g only in old format ]
422 * Finally, there is a line saying "Private-MAC: " plus a hex
423 * representation of a HMAC-SHA-1 of:
425 * string name of algorithm ("ssh-dss", "ssh-rsa")
426 * string encryption type
429 * string private-plaintext (the plaintext version of the
430 * private part, including the final
433 * The key to the MAC is itself a SHA-1 hash of:
435 * data "putty-private-key-file-mac-key"
438 * (An empty passphrase is used for unencrypted keys.)
440 * If the key is encrypted, the encryption key is derived from the
441 * passphrase by means of a succession of SHA-1 hashes. Each hash
444 * uint32 sequence-number
447 * where the sequence-number increases from zero. As many of these
448 * hashes are used as necessary.
450 * For backwards compatibility with snapshots between 0.51 and
451 * 0.52, we also support the older key file format, which begins
452 * with "PuTTY-User-Key-File-1" (version number differs). In this
453 * format the Private-MAC: field only covers the private-plaintext
454 * field and nothing else (and without the 4-byte string length on
455 * the front too). Moreover, the Private-MAC: field can be replaced
456 * with a Private-Hash: field which is a plain SHA-1 hash instead of
457 * an HMAC (this was generated for unencrypted keys).
460 static int read_header(FILE * fp
, char *header
)
467 if (c
== '\n' || c
== '\r' || c
== EOF
)
468 return 0; /* failure */
474 return 1; /* success! */
477 return 0; /* failure */
481 return 0; /* failure */
484 static char *read_body(FILE * fp
)
492 text
= snewn(size
, char);
498 if (c
== '\r' || c
== '\n') {
500 if (c
!= '\r' && c
!= '\n' && c
!= EOF
)
508 if (len
+ 1 >= size
) {
510 text
= sresize(text
, size
, char);
517 int base64_decode_atom(char *atom
, unsigned char *out
)
524 for (i
= 0; i
< 4; i
++) {
526 if (c
>= 'A' && c
<= 'Z')
528 else if (c
>= 'a' && c
<= 'z')
530 else if (c
>= '0' && c
<= '9')
539 return 0; /* invalid atom */
543 if (vals
[0] == -1 || vals
[1] == -1)
545 if (vals
[2] == -1 && vals
[3] != -1)
550 else if (vals
[2] != -1)
555 word
= ((vals
[0] << 18) |
556 (vals
[1] << 12) | ((vals
[2] & 0x3F) << 6) | (vals
[3] & 0x3F));
557 out
[0] = (word
>> 16) & 0xFF;
559 out
[1] = (word
>> 8) & 0xFF;
561 out
[2] = word
& 0xFF;
565 static unsigned char *read_blob(FILE * fp
, int nlines
, int *bloblen
)
572 /* We expect at most 64 base64 characters, ie 48 real bytes, per line. */
573 blob
= snewn(48 * nlines
, unsigned char);
575 for (i
= 0; i
< nlines
; i
++) {
576 line
= read_body(fp
);
581 linelen
= strlen(line
);
582 if (linelen
% 4 != 0 || linelen
> 64) {
587 for (j
= 0; j
< linelen
; j
+= 4) {
588 k
= base64_decode_atom(line
+ j
, blob
+ len
);
603 * Magic error return value for when the passphrase is wrong.
605 struct ssh2_userkey ssh2_wrong_passphrase
= {
609 const struct ssh_signkey
*find_pubkey_alg(const char *name
)
611 if (!strcmp(name
, "ssh-rsa"))
613 else if (!strcmp(name
, "ssh-dss"))
619 struct ssh2_userkey
*ssh2_load_userkey(const Filename
*filename
,
620 char *passphrase
, const char **errorstr
)
623 char header
[40], *b
, *encryption
, *comment
, *mac
;
624 const struct ssh_signkey
*alg
;
625 struct ssh2_userkey
*ret
;
626 int cipher
, cipherblk
;
627 unsigned char *public_blob
, *private_blob
;
628 int public_blob_len
, private_blob_len
;
629 int i
, is_mac
, old_fmt
;
630 int passlen
= passphrase ?
strlen(passphrase
) : 0;
631 const char *error
= NULL
;
633 ret
= NULL
; /* return NULL for most errors */
634 encryption
= comment
= mac
= NULL
;
635 public_blob
= private_blob
= NULL
;
637 fp
= f_open(*filename
, "rb");
639 error
= "can't open file";
643 /* Read the first header line which contains the key type. */
644 if (!read_header(fp
, header
))
646 if (0 == strcmp(header
, "PuTTY-User-Key-File-2")) {
648 } else if (0 == strcmp(header
, "PuTTY-User-Key-File-1")) {
649 /* this is an old key file; warn and then continue */
650 old_keyfile_warning();
653 error
= "not a PuTTY SSH-2 private key";
656 error
= "file format error";
657 if ((b
= read_body(fp
)) == NULL
)
659 /* Select key algorithm structure. */
660 alg
= find_pubkey_alg(b
);
667 /* Read the Encryption header line. */
668 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Encryption"))
670 if ((encryption
= read_body(fp
)) == NULL
)
672 if (!strcmp(encryption
, "aes256-cbc")) {
675 } else if (!strcmp(encryption
, "none")) {
683 /* Read the Comment header line. */
684 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Comment"))
686 if ((comment
= read_body(fp
)) == NULL
)
689 /* Read the Public-Lines header line and the public blob. */
690 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Public-Lines"))
692 if ((b
= read_body(fp
)) == NULL
)
696 if ((public_blob
= read_blob(fp
, i
, &public_blob_len
)) == NULL
)
699 /* Read the Private-Lines header line and the Private blob. */
700 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Private-Lines"))
702 if ((b
= read_body(fp
)) == NULL
)
706 if ((private_blob
= read_blob(fp
, i
, &private_blob_len
)) == NULL
)
709 /* Read the Private-MAC or Private-Hash header line. */
710 if (!read_header(fp
, header
))
712 if (0 == strcmp(header
, "Private-MAC")) {
713 if ((mac
= read_body(fp
)) == NULL
)
716 } else if (0 == strcmp(header
, "Private-Hash") && old_fmt
) {
717 if ((mac
= read_body(fp
)) == NULL
)
727 * Decrypt the private blob.
730 unsigned char key
[40];
735 if (private_blob_len
% cipherblk
)
739 SHA_Bytes(&s
, "\0\0\0\0", 4);
740 SHA_Bytes(&s
, passphrase
, passlen
);
741 SHA_Final(&s
, key
+ 0);
743 SHA_Bytes(&s
, "\0\0\0\1", 4);
744 SHA_Bytes(&s
, passphrase
, passlen
);
745 SHA_Final(&s
, key
+ 20);
746 aes256_decrypt_pubkey(key
, private_blob
, private_blob_len
);
754 unsigned char binary
[20];
755 unsigned char *macdata
;
760 /* MAC (or hash) only covers the private blob. */
761 macdata
= private_blob
;
762 maclen
= private_blob_len
;
766 int namelen
= strlen(alg
->name
);
767 int enclen
= strlen(encryption
);
768 int commlen
= strlen(comment
);
769 maclen
= (4 + namelen
+
772 4 + public_blob_len
+
773 4 + private_blob_len
);
774 macdata
= snewn(maclen
, unsigned char);
776 #define DO_STR(s,len) PUT_32BIT(p,(len));memcpy(p+4,(s),(len));p+=4+(len)
777 DO_STR(alg
->name
, namelen
);
778 DO_STR(encryption
, enclen
);
779 DO_STR(comment
, commlen
);
780 DO_STR(public_blob
, public_blob_len
);
781 DO_STR(private_blob
, private_blob_len
);
788 unsigned char mackey
[20];
789 char header
[] = "putty-private-key-file-mac-key";
792 SHA_Bytes(&s
, header
, sizeof(header
)-1);
793 if (cipher
&& passphrase
)
794 SHA_Bytes(&s
, passphrase
, passlen
);
795 SHA_Final(&s
, mackey
);
797 hmac_sha1_simple(mackey
, 20, macdata
, maclen
, binary
);
799 memset(mackey
, 0, sizeof(mackey
));
800 memset(&s
, 0, sizeof(s
));
802 SHA_Simple(macdata
, maclen
, binary
);
806 memset(macdata
, 0, maclen
);
810 for (i
= 0; i
< 20; i
++)
811 sprintf(realmac
+ 2 * i
, "%02x", binary
[i
]);
813 if (strcmp(mac
, realmac
)) {
814 /* An incorrect MAC is an unconditional Error if the key is
815 * unencrypted. Otherwise, it means Wrong Passphrase. */
817 error
= "wrong passphrase";
818 ret
= SSH2_WRONG_PASSPHRASE
;
820 error
= "MAC failed";
829 * Create and return the key.
831 ret
= snew(struct ssh2_userkey
);
833 ret
->comment
= comment
;
834 ret
->data
= alg
->createkey(public_blob
, public_blob_len
,
835 private_blob
, private_blob_len
);
840 error
= "createkey failed";
871 char *ssh2_userkey_loadpub(const Filename
*filename
, char **algorithm
,
872 int *pub_blob_len
, char **commentptr
,
873 const char **errorstr
)
877 const struct ssh_signkey
*alg
;
878 unsigned char *public_blob
;
881 const char *error
= NULL
;
886 fp
= f_open(*filename
, "rb");
888 error
= "can't open file";
892 /* Read the first header line which contains the key type. */
893 if (!read_header(fp
, header
)
894 || (0 != strcmp(header
, "PuTTY-User-Key-File-2") &&
895 0 != strcmp(header
, "PuTTY-User-Key-File-1"))) {
896 error
= "not a PuTTY SSH-2 private key";
899 error
= "file format error";
900 if ((b
= read_body(fp
)) == NULL
)
902 /* Select key algorithm structure. */
903 alg
= find_pubkey_alg(b
);
910 /* Read the Encryption header line. */
911 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Encryption"))
913 if ((b
= read_body(fp
)) == NULL
)
915 sfree(b
); /* we don't care */
917 /* Read the Comment header line. */
918 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Comment"))
920 if ((comment
= read_body(fp
)) == NULL
)
924 *commentptr
= comment
;
928 /* Read the Public-Lines header line and the public blob. */
929 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Public-Lines"))
931 if ((b
= read_body(fp
)) == NULL
)
935 if ((public_blob
= read_blob(fp
, i
, &public_blob_len
)) == NULL
)
940 *pub_blob_len
= public_blob_len
;
942 *algorithm
= alg
->name
;
943 return (char *)public_blob
;
958 int ssh2_userkey_encrypted(const Filename
*filename
, char **commentptr
)
961 char header
[40], *b
, *comment
;
967 fp
= f_open(*filename
, "rb");
970 if (!read_header(fp
, header
)
971 || (0 != strcmp(header
, "PuTTY-User-Key-File-2") &&
972 0 != strcmp(header
, "PuTTY-User-Key-File-1"))) {
976 if ((b
= read_body(fp
)) == NULL
) {
980 sfree(b
); /* we don't care about key type here */
981 /* Read the Encryption header line. */
982 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Encryption")) {
986 if ((b
= read_body(fp
)) == NULL
) {
991 /* Read the Comment header line. */
992 if (!read_header(fp
, header
) || 0 != strcmp(header
, "Comment")) {
997 if ((comment
= read_body(fp
)) == NULL
) {
1004 *commentptr
= comment
;
1007 if (!strcmp(b
, "aes256-cbc"))
1015 int base64_lines(int datalen
)
1017 /* When encoding, we use 64 chars/line, which equals 48 real chars. */
1018 return (datalen
+ 47) / 48;
1021 void base64_encode(FILE * fp
, unsigned char *data
, int datalen
, int cpl
)
1027 while (datalen
> 0) {
1028 n
= (datalen
< 3 ? datalen
: 3);
1029 base64_encode_atom(data
, n
, out
);
1032 for (i
= 0; i
< 4; i
++) {
1033 if (linelen
>= cpl
) {
1044 int ssh2_save_userkey(const Filename
*filename
, struct ssh2_userkey
*key
,
1048 unsigned char *pub_blob
, *priv_blob
, *priv_blob_encrypted
;
1049 int pub_blob_len
, priv_blob_len
, priv_encrypted_len
;
1054 unsigned char priv_mac
[20];
1057 * Fetch the key component blobs.
1059 pub_blob
= key
->alg
->public_blob(key
->data
, &pub_blob_len
);
1060 priv_blob
= key
->alg
->private_blob(key
->data
, &priv_blob_len
);
1061 if (!pub_blob
|| !priv_blob
) {
1068 * Determine encryption details, and encrypt the private blob.
1071 cipherstr
= "aes256-cbc";
1077 priv_encrypted_len
= priv_blob_len
+ cipherblk
- 1;
1078 priv_encrypted_len
-= priv_encrypted_len
% cipherblk
;
1079 priv_blob_encrypted
= snewn(priv_encrypted_len
, unsigned char);
1080 memset(priv_blob_encrypted
, 0, priv_encrypted_len
);
1081 memcpy(priv_blob_encrypted
, priv_blob
, priv_blob_len
);
1082 /* Create padding based on the SHA hash of the unpadded blob. This prevents
1083 * too easy a known-plaintext attack on the last block. */
1084 SHA_Simple(priv_blob
, priv_blob_len
, priv_mac
);
1085 assert(priv_encrypted_len
- priv_blob_len
< 20);
1086 memcpy(priv_blob_encrypted
+ priv_blob_len
, priv_mac
,
1087 priv_encrypted_len
- priv_blob_len
);
1089 /* Now create the MAC. */
1091 unsigned char *macdata
;
1094 int namelen
= strlen(key
->alg
->name
);
1095 int enclen
= strlen(cipherstr
);
1096 int commlen
= strlen(key
->comment
);
1098 unsigned char mackey
[20];
1099 char header
[] = "putty-private-key-file-mac-key";
1101 maclen
= (4 + namelen
+
1105 4 + priv_encrypted_len
);
1106 macdata
= snewn(maclen
, unsigned char);
1108 #define DO_STR(s,len) PUT_32BIT(p,(len));memcpy(p+4,(s),(len));p+=4+(len)
1109 DO_STR(key
->alg
->name
, namelen
);
1110 DO_STR(cipherstr
, enclen
);
1111 DO_STR(key
->comment
, commlen
);
1112 DO_STR(pub_blob
, pub_blob_len
);
1113 DO_STR(priv_blob_encrypted
, priv_encrypted_len
);
1116 SHA_Bytes(&s
, header
, sizeof(header
)-1);
1118 SHA_Bytes(&s
, passphrase
, strlen(passphrase
));
1119 SHA_Final(&s
, mackey
);
1120 hmac_sha1_simple(mackey
, 20, macdata
, maclen
, priv_mac
);
1121 memset(macdata
, 0, maclen
);
1123 memset(mackey
, 0, sizeof(mackey
));
1124 memset(&s
, 0, sizeof(s
));
1128 unsigned char key
[40];
1131 passlen
= strlen(passphrase
);
1134 SHA_Bytes(&s
, "\0\0\0\0", 4);
1135 SHA_Bytes(&s
, passphrase
, passlen
);
1136 SHA_Final(&s
, key
+ 0);
1138 SHA_Bytes(&s
, "\0\0\0\1", 4);
1139 SHA_Bytes(&s
, passphrase
, passlen
);
1140 SHA_Final(&s
, key
+ 20);
1141 aes256_encrypt_pubkey(key
, priv_blob_encrypted
,
1142 priv_encrypted_len
);
1144 memset(key
, 0, sizeof(key
));
1145 memset(&s
, 0, sizeof(s
));
1148 fp
= f_open(*filename
, "w");
1151 fprintf(fp
, "PuTTY-User-Key-File-2: %s\n", key
->alg
->name
);
1152 fprintf(fp
, "Encryption: %s\n", cipherstr
);
1153 fprintf(fp
, "Comment: %s\n", key
->comment
);
1154 fprintf(fp
, "Public-Lines: %d\n", base64_lines(pub_blob_len
));
1155 base64_encode(fp
, pub_blob
, pub_blob_len
, 64);
1156 fprintf(fp
, "Private-Lines: %d\n", base64_lines(priv_encrypted_len
));
1157 base64_encode(fp
, priv_blob_encrypted
, priv_encrypted_len
, 64);
1158 fprintf(fp
, "Private-MAC: ");
1159 for (i
= 0; i
< 20; i
++)
1160 fprintf(fp
, "%02x", priv_mac
[i
]);
1165 memset(priv_blob
, 0, priv_blob_len
);
1167 sfree(priv_blob_encrypted
);
1171 /* ----------------------------------------------------------------------
1172 * A function to determine the type of a private key file. Returns
1173 * 0 on failure, 1 or 2 on success.
1175 int key_type(const Filename
*filename
)
1179 const char putty2_sig
[] = "PuTTY-User-Key-File-";
1180 const char sshcom_sig
[] = "---- BEGIN SSH2 ENCRYPTED PRIVAT";
1181 const char openssh_sig
[] = "-----BEGIN ";
1184 fp
= f_open(*filename
, "r");
1186 return SSH_KEYTYPE_UNOPENABLE
;
1187 i
= fread(buf
, 1, sizeof(buf
), fp
);
1190 return SSH_KEYTYPE_UNOPENABLE
;
1192 return SSH_KEYTYPE_UNKNOWN
;
1193 if (!memcmp(buf
, rsa_signature
, sizeof(rsa_signature
)-1))
1194 return SSH_KEYTYPE_SSH1
;
1195 if (!memcmp(buf
, putty2_sig
, sizeof(putty2_sig
)-1))
1196 return SSH_KEYTYPE_SSH2
;
1197 if (!memcmp(buf
, openssh_sig
, sizeof(openssh_sig
)-1))
1198 return SSH_KEYTYPE_OPENSSH
;
1199 if (!memcmp(buf
, sshcom_sig
, sizeof(sshcom_sig
)-1))
1200 return SSH_KEYTYPE_SSHCOM
;
1201 return SSH_KEYTYPE_UNKNOWN
; /* unrecognised or EOF */
1205 * Convert the type word to a string, for `wrong type' error
1208 char *key_type_to_str(int type
)
1211 case SSH_KEYTYPE_UNOPENABLE
: return "unable to open file"; break;
1212 case SSH_KEYTYPE_UNKNOWN
: return "not a private key"; break;
1213 case SSH_KEYTYPE_SSH1
: return "SSH-1 private key"; break;
1214 case SSH_KEYTYPE_SSH2
: return "PuTTY SSH-2 private key"; break;
1215 case SSH_KEYTYPE_OPENSSH
: return "OpenSSH SSH-2 private key"; break;
1216 case SSH_KEYTYPE_SSHCOM
: return "ssh.com SSH-2 private key"; break;
1217 default: return "INTERNAL ERROR"; break;