Sebastian Kuschel reports that pfd_closing can be called for a socket
[u/mdw/putty] / ssh.h
1 #include <stdio.h>
2 #include <string.h>
3
4 #include "puttymem.h"
5 #include "tree234.h"
6 #include "network.h"
7 #include "int64.h"
8 #include "misc.h"
9
10 struct ssh_channel;
11
12 extern int sshfwd_write(struct ssh_channel *c, char *, int);
13 extern void sshfwd_write_eof(struct ssh_channel *c);
14 extern void sshfwd_unclean_close(struct ssh_channel *c);
15 extern void sshfwd_unthrottle(struct ssh_channel *c, int bufsize);
16
17 /*
18 * Useful thing.
19 */
20 #ifndef lenof
21 #define lenof(x) ( (sizeof((x))) / (sizeof(*(x))))
22 #endif
23
24 #define SSH_CIPHER_IDEA 1
25 #define SSH_CIPHER_DES 2
26 #define SSH_CIPHER_3DES 3
27 #define SSH_CIPHER_BLOWFISH 6
28
29 #ifdef MSCRYPTOAPI
30 #define APIEXTRA 8
31 #else
32 #define APIEXTRA 0
33 #endif
34
35 #ifndef BIGNUM_INTERNAL
36 typedef void *Bignum;
37 #endif
38
39 struct RSAKey {
40 int bits;
41 int bytes;
42 #ifdef MSCRYPTOAPI
43 unsigned long exponent;
44 unsigned char *modulus;
45 #else
46 Bignum modulus;
47 Bignum exponent;
48 Bignum private_exponent;
49 Bignum p;
50 Bignum q;
51 Bignum iqmp;
52 #endif
53 char *comment;
54 };
55
56 struct dss_key {
57 Bignum p, q, g, y, x;
58 };
59
60 int makekey(unsigned char *data, int len, struct RSAKey *result,
61 unsigned char **keystr, int order);
62 int makeprivate(unsigned char *data, int len, struct RSAKey *result);
63 int rsaencrypt(unsigned char *data, int length, struct RSAKey *key);
64 Bignum rsadecrypt(Bignum input, struct RSAKey *key);
65 void rsasign(unsigned char *data, int length, struct RSAKey *key);
66 void rsasanitise(struct RSAKey *key);
67 int rsastr_len(struct RSAKey *key);
68 void rsastr_fmt(char *str, struct RSAKey *key);
69 void rsa_fingerprint(char *str, int len, struct RSAKey *key);
70 int rsa_verify(struct RSAKey *key);
71 unsigned char *rsa_public_blob(struct RSAKey *key, int *len);
72 int rsa_public_blob_len(void *data, int maxlen);
73 void freersakey(struct RSAKey *key);
74
75 #ifndef PUTTY_UINT32_DEFINED
76 /* This makes assumptions about the int type. */
77 typedef unsigned int uint32;
78 #define PUTTY_UINT32_DEFINED
79 #endif
80 typedef uint32 word32;
81
82 unsigned long crc32_compute(const void *s, size_t len);
83 unsigned long crc32_update(unsigned long crc_input, const void *s, size_t len);
84
85 /* SSH CRC compensation attack detector */
86 void *crcda_make_context(void);
87 void crcda_free_context(void *handle);
88 int detect_attack(void *handle, unsigned char *buf, uint32 len,
89 unsigned char *IV);
90
91 /*
92 * SSH2 RSA key exchange functions
93 */
94 struct ssh_hash;
95 void *ssh_rsakex_newkey(char *data, int len);
96 void ssh_rsakex_freekey(void *key);
97 int ssh_rsakex_klen(void *key);
98 void ssh_rsakex_encrypt(const struct ssh_hash *h, unsigned char *in, int inlen,
99 unsigned char *out, int outlen,
100 void *key);
101
102 typedef struct {
103 uint32 h[4];
104 } MD5_Core_State;
105
106 struct MD5Context {
107 #ifdef MSCRYPTOAPI
108 unsigned long hHash;
109 #else
110 MD5_Core_State core;
111 unsigned char block[64];
112 int blkused;
113 uint32 lenhi, lenlo;
114 #endif
115 };
116
117 void MD5Init(struct MD5Context *context);
118 void MD5Update(struct MD5Context *context, unsigned char const *buf,
119 unsigned len);
120 void MD5Final(unsigned char digest[16], struct MD5Context *context);
121 void MD5Simple(void const *p, unsigned len, unsigned char output[16]);
122
123 void *hmacmd5_make_context(void);
124 void hmacmd5_free_context(void *handle);
125 void hmacmd5_key(void *handle, void const *key, int len);
126 void hmacmd5_do_hmac(void *handle, unsigned char const *blk, int len,
127 unsigned char *hmac);
128
129 typedef struct {
130 uint32 h[5];
131 unsigned char block[64];
132 int blkused;
133 uint32 lenhi, lenlo;
134 } SHA_State;
135 void SHA_Init(SHA_State * s);
136 void SHA_Bytes(SHA_State * s, const void *p, int len);
137 void SHA_Final(SHA_State * s, unsigned char *output);
138 void SHA_Simple(const void *p, int len, unsigned char *output);
139
140 void hmac_sha1_simple(void *key, int keylen, void *data, int datalen,
141 unsigned char *output);
142 typedef struct {
143 uint32 h[8];
144 unsigned char block[64];
145 int blkused;
146 uint32 lenhi, lenlo;
147 } SHA256_State;
148 void SHA256_Init(SHA256_State * s);
149 void SHA256_Bytes(SHA256_State * s, const void *p, int len);
150 void SHA256_Final(SHA256_State * s, unsigned char *output);
151 void SHA256_Simple(const void *p, int len, unsigned char *output);
152
153 typedef struct {
154 uint64 h[8];
155 unsigned char block[128];
156 int blkused;
157 uint32 len[4];
158 } SHA512_State;
159 void SHA512_Init(SHA512_State * s);
160 void SHA512_Bytes(SHA512_State * s, const void *p, int len);
161 void SHA512_Final(SHA512_State * s, unsigned char *output);
162 void SHA512_Simple(const void *p, int len, unsigned char *output);
163
164 struct ssh_cipher {
165 void *(*make_context)(void);
166 void (*free_context)(void *);
167 void (*sesskey) (void *, unsigned char *key); /* for SSH-1 */
168 void (*encrypt) (void *, unsigned char *blk, int len);
169 void (*decrypt) (void *, unsigned char *blk, int len);
170 int blksize;
171 char *text_name;
172 };
173
174 struct ssh2_cipher {
175 void *(*make_context)(void);
176 void (*free_context)(void *);
177 void (*setiv) (void *, unsigned char *key); /* for SSH-2 */
178 void (*setkey) (void *, unsigned char *key);/* for SSH-2 */
179 void (*encrypt) (void *, unsigned char *blk, int len);
180 void (*decrypt) (void *, unsigned char *blk, int len);
181 char *name;
182 int blksize;
183 int keylen;
184 unsigned int flags;
185 #define SSH_CIPHER_IS_CBC 1
186 char *text_name;
187 };
188
189 struct ssh2_ciphers {
190 int nciphers;
191 const struct ssh2_cipher *const *list;
192 };
193
194 struct ssh_mac {
195 void *(*make_context)(void);
196 void (*free_context)(void *);
197 void (*setkey) (void *, unsigned char *key);
198 /* whole-packet operations */
199 void (*generate) (void *, unsigned char *blk, int len, unsigned long seq);
200 int (*verify) (void *, unsigned char *blk, int len, unsigned long seq);
201 /* partial-packet operations */
202 void (*start) (void *);
203 void (*bytes) (void *, unsigned char const *, int);
204 void (*genresult) (void *, unsigned char *);
205 int (*verresult) (void *, unsigned char const *);
206 char *name;
207 int len;
208 char *text_name;
209 };
210
211 struct ssh_hash {
212 void *(*init)(void); /* also allocates context */
213 void (*bytes)(void *, void *, int);
214 void (*final)(void *, unsigned char *); /* also frees context */
215 int hlen; /* output length in bytes */
216 char *text_name;
217 };
218
219 struct ssh_kex {
220 char *name, *groupname;
221 enum { KEXTYPE_DH, KEXTYPE_RSA } main_type;
222 /* For DH */
223 const unsigned char *pdata, *gdata; /* NULL means group exchange */
224 int plen, glen;
225 const struct ssh_hash *hash;
226 };
227
228 struct ssh_kexes {
229 int nkexes;
230 const struct ssh_kex *const *list;
231 };
232
233 struct ssh_signkey {
234 void *(*newkey) (char *data, int len);
235 void (*freekey) (void *key);
236 char *(*fmtkey) (void *key);
237 unsigned char *(*public_blob) (void *key, int *len);
238 unsigned char *(*private_blob) (void *key, int *len);
239 void *(*createkey) (unsigned char *pub_blob, int pub_len,
240 unsigned char *priv_blob, int priv_len);
241 void *(*openssh_createkey) (unsigned char **blob, int *len);
242 int (*openssh_fmtkey) (void *key, unsigned char *blob, int len);
243 int (*pubkey_bits) (void *blob, int len);
244 char *(*fingerprint) (void *key);
245 int (*verifysig) (void *key, char *sig, int siglen,
246 char *data, int datalen);
247 unsigned char *(*sign) (void *key, char *data, int datalen,
248 int *siglen);
249 char *name;
250 char *keytype; /* for host key cache */
251 };
252
253 struct ssh_compress {
254 char *name;
255 /* For zlib@openssh.com: if non-NULL, this name will be considered once
256 * userauth has completed successfully. */
257 char *delayed_name;
258 void *(*compress_init) (void);
259 void (*compress_cleanup) (void *);
260 int (*compress) (void *, unsigned char *block, int len,
261 unsigned char **outblock, int *outlen);
262 void *(*decompress_init) (void);
263 void (*decompress_cleanup) (void *);
264 int (*decompress) (void *, unsigned char *block, int len,
265 unsigned char **outblock, int *outlen);
266 int (*disable_compression) (void *);
267 char *text_name;
268 };
269
270 struct ssh2_userkey {
271 const struct ssh_signkey *alg; /* the key algorithm */
272 void *data; /* the key data */
273 char *comment; /* the key comment */
274 };
275
276 /* The maximum length of any hash algorithm used in kex. (bytes) */
277 #define SSH2_KEX_MAX_HASH_LEN (32) /* SHA-256 */
278
279 extern const struct ssh_cipher ssh_3des;
280 extern const struct ssh_cipher ssh_des;
281 extern const struct ssh_cipher ssh_blowfish_ssh1;
282 extern const struct ssh2_ciphers ssh2_3des;
283 extern const struct ssh2_ciphers ssh2_des;
284 extern const struct ssh2_ciphers ssh2_aes;
285 extern const struct ssh2_ciphers ssh2_blowfish;
286 extern const struct ssh2_ciphers ssh2_arcfour;
287 extern const struct ssh_hash ssh_sha1;
288 extern const struct ssh_hash ssh_sha256;
289 extern const struct ssh_kexes ssh_diffiehellman_group1;
290 extern const struct ssh_kexes ssh_diffiehellman_group14;
291 extern const struct ssh_kexes ssh_diffiehellman_gex;
292 extern const struct ssh_kexes ssh_rsa_kex;
293 extern const struct ssh_signkey ssh_dss;
294 extern const struct ssh_signkey ssh_rsa;
295 extern const struct ssh_mac ssh_hmac_md5;
296 extern const struct ssh_mac ssh_hmac_sha1;
297 extern const struct ssh_mac ssh_hmac_sha1_buggy;
298 extern const struct ssh_mac ssh_hmac_sha1_96;
299 extern const struct ssh_mac ssh_hmac_sha1_96_buggy;
300 extern const struct ssh_mac ssh_hmac_sha256;
301
302 void *aes_make_context(void);
303 void aes_free_context(void *handle);
304 void aes128_key(void *handle, unsigned char *key);
305 void aes192_key(void *handle, unsigned char *key);
306 void aes256_key(void *handle, unsigned char *key);
307 void aes_iv(void *handle, unsigned char *iv);
308 void aes_ssh2_encrypt_blk(void *handle, unsigned char *blk, int len);
309 void aes_ssh2_decrypt_blk(void *handle, unsigned char *blk, int len);
310
311 /*
312 * PuTTY version number formatted as an SSH version string.
313 */
314 extern char sshver[];
315
316 /*
317 * Gross hack: pscp will try to start SFTP but fall back to scp1 if
318 * that fails. This variable is the means by which scp.c can reach
319 * into the SSH code and find out which one it got.
320 */
321 extern int ssh_fallback_cmd(void *handle);
322
323 #ifndef MSCRYPTOAPI
324 void SHATransform(word32 * digest, word32 * data);
325 #endif
326
327 int random_byte(void);
328 void random_add_noise(void *noise, int length);
329 void random_add_heavynoise(void *noise, int length);
330
331 void logevent(void *, const char *);
332
333 /* Allocate and register a new channel for port forwarding */
334 void *new_sock_channel(void *handle, Socket s);
335 void ssh_send_port_open(void *channel, char *hostname, int port, char *org);
336
337 /* Exports from portfwd.c */
338 extern const char *pfd_newconnect(Socket * s, char *hostname, int port,
339 void *c, Conf *conf, int addressfamily);
340 /* desthost == NULL indicates dynamic (SOCKS) port forwarding */
341 extern const char *pfd_addforward(char *desthost, int destport, char *srcaddr,
342 int port, void *backhandle, Conf *conf,
343 void **sockdata, int address_family);
344 extern void pfd_close(Socket s);
345 extern void pfd_terminate(void *sockdata);
346 extern int pfd_send(Socket s, char *data, int len);
347 extern void pfd_send_eof(Socket s);
348 extern void pfd_confirm(Socket s);
349 extern void pfd_unthrottle(Socket s);
350 extern void pfd_override_throttle(Socket s, int enable);
351
352 /* Exports from x11fwd.c */
353 enum {
354 X11_TRANS_IPV4 = 0, X11_TRANS_IPV6 = 6, X11_TRANS_UNIX = 256
355 };
356 struct X11Display {
357 /* Broken-down components of the display name itself */
358 int unixdomain;
359 char *hostname;
360 int displaynum;
361 int screennum;
362 /* OSX sometimes replaces all the above with a full Unix-socket pathname */
363 char *unixsocketpath;
364
365 /* PuTTY networking SockAddr to connect to the display, and associated
366 * gubbins */
367 SockAddr addr;
368 int port;
369 char *realhost;
370
371 /* Auth details we invented for the virtual display on the SSH server. */
372 int remoteauthproto;
373 unsigned char *remoteauthdata;
374 int remoteauthdatalen;
375 char *remoteauthprotoname;
376 char *remoteauthdatastring;
377
378 /* Our local auth details for talking to the real X display. */
379 int localauthproto;
380 unsigned char *localauthdata;
381 int localauthdatalen;
382
383 /*
384 * Used inside x11fwd.c to remember recently seen
385 * XDM-AUTHORIZATION-1 strings, to avoid replay attacks.
386 */
387 tree234 *xdmseen;
388 };
389 /*
390 * x11_setup_display() parses the display variable and fills in an
391 * X11Display structure. Some remote auth details are invented;
392 * the supplied authtype parameter configures the preferred
393 * authorisation protocol to use at the remote end. The local auth
394 * details are looked up by calling platform_get_x11_auth.
395 */
396 extern struct X11Display *x11_setup_display(char *display, int authtype,
397 Conf *);
398 void x11_free_display(struct X11Display *disp);
399 extern const char *x11_init(Socket *, struct X11Display *, void *,
400 const char *, int, Conf *);
401 extern void x11_close(Socket);
402 extern int x11_send(Socket, char *, int);
403 extern void x11_send_eof(Socket s);
404 extern void x11_unthrottle(Socket s);
405 extern void x11_override_throttle(Socket s, int enable);
406 char *x11_display(const char *display);
407 /* Platform-dependent X11 functions */
408 extern void platform_get_x11_auth(struct X11Display *display, Conf *);
409 /* examine a mostly-filled-in X11Display and fill in localauth* */
410 extern const int platform_uses_x11_unix_by_default;
411 /* choose default X transport in the absence of a specified one */
412 SockAddr platform_get_x11_unix_address(const char *path, int displaynum);
413 /* make up a SockAddr naming the address for displaynum */
414 char *platform_get_x_display(void);
415 /* allocated local X display string, if any */
416 /* Callbacks in x11.c usable _by_ platform X11 functions */
417 /*
418 * This function does the job of platform_get_x11_auth, provided
419 * it is told where to find a normally formatted .Xauthority file:
420 * it opens that file, parses it to find an auth record which
421 * matches the display details in "display", and fills in the
422 * localauth fields.
423 *
424 * It is expected that most implementations of
425 * platform_get_x11_auth() will work by finding their system's
426 * .Xauthority file, adjusting the display details if necessary
427 * for local oddities like Unix-domain socket transport, and
428 * calling this function to do the rest of the work.
429 */
430 void x11_get_auth_from_authfile(struct X11Display *display,
431 const char *authfilename);
432
433 Bignum copybn(Bignum b);
434 Bignum bn_power_2(int n);
435 void bn_restore_invariant(Bignum b);
436 Bignum bignum_from_long(unsigned long n);
437 void freebn(Bignum b);
438 Bignum modpow(Bignum base, Bignum exp, Bignum mod);
439 Bignum modmul(Bignum a, Bignum b, Bignum mod);
440 void decbn(Bignum n);
441 extern Bignum Zero, One;
442 Bignum bignum_from_bytes(const unsigned char *data, int nbytes);
443 int ssh1_read_bignum(const unsigned char *data, int len, Bignum * result);
444 int bignum_bitcount(Bignum bn);
445 int ssh1_bignum_length(Bignum bn);
446 int ssh2_bignum_length(Bignum bn);
447 int bignum_byte(Bignum bn, int i);
448 int bignum_bit(Bignum bn, int i);
449 void bignum_set_bit(Bignum bn, int i, int value);
450 int ssh1_write_bignum(void *data, Bignum bn);
451 Bignum biggcd(Bignum a, Bignum b);
452 unsigned short bignum_mod_short(Bignum number, unsigned short modulus);
453 Bignum bignum_add_long(Bignum number, unsigned long addend);
454 Bignum bigadd(Bignum a, Bignum b);
455 Bignum bigsub(Bignum a, Bignum b);
456 Bignum bigmul(Bignum a, Bignum b);
457 Bignum bigmuladd(Bignum a, Bignum b, Bignum addend);
458 Bignum bigdiv(Bignum a, Bignum b);
459 Bignum bigmod(Bignum a, Bignum b);
460 Bignum modinv(Bignum number, Bignum modulus);
461 Bignum bignum_bitmask(Bignum number);
462 Bignum bignum_rshift(Bignum number, int shift);
463 int bignum_cmp(Bignum a, Bignum b);
464 char *bignum_decimal(Bignum x);
465
466 #ifdef DEBUG
467 void diagbn(char *prefix, Bignum md);
468 #endif
469
470 void *dh_setup_group(const struct ssh_kex *kex);
471 void *dh_setup_gex(Bignum pval, Bignum gval);
472 void dh_cleanup(void *);
473 Bignum dh_create_e(void *, int nbits);
474 Bignum dh_find_K(void *, Bignum f);
475
476 int loadrsakey(const Filename *filename, struct RSAKey *key,
477 char *passphrase, const char **errorstr);
478 int rsakey_encrypted(const Filename *filename, char **comment);
479 int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen,
480 char **commentptr, const char **errorstr);
481
482 int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase);
483
484 extern int base64_decode_atom(char *atom, unsigned char *out);
485 extern int base64_lines(int datalen);
486 extern void base64_encode_atom(unsigned char *data, int n, char *out);
487 extern void base64_encode(FILE *fp, unsigned char *data, int datalen, int cpl);
488
489 /* ssh2_load_userkey can return this as an error */
490 extern struct ssh2_userkey ssh2_wrong_passphrase;
491 #define SSH2_WRONG_PASSPHRASE (&ssh2_wrong_passphrase)
492
493 int ssh2_userkey_encrypted(const Filename *filename, char **comment);
494 struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
495 char *passphrase, const char **errorstr);
496 unsigned char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
497 int *pub_blob_len, char **commentptr,
498 const char **errorstr);
499 int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key,
500 char *passphrase);
501 const struct ssh_signkey *find_pubkey_alg(const char *name);
502
503 enum {
504 SSH_KEYTYPE_UNOPENABLE,
505 SSH_KEYTYPE_UNKNOWN,
506 SSH_KEYTYPE_SSH1, SSH_KEYTYPE_SSH2,
507 SSH_KEYTYPE_OPENSSH, SSH_KEYTYPE_SSHCOM
508 };
509 int key_type(const Filename *filename);
510 char *key_type_to_str(int type);
511
512 int import_possible(int type);
513 int import_target_type(int type);
514 int import_encrypted(const Filename *filename, int type, char **comment);
515 int import_ssh1(const Filename *filename, int type,
516 struct RSAKey *key, char *passphrase, const char **errmsg_p);
517 struct ssh2_userkey *import_ssh2(const Filename *filename, int type,
518 char *passphrase, const char **errmsg_p);
519 int export_ssh1(const Filename *filename, int type,
520 struct RSAKey *key, char *passphrase);
521 int export_ssh2(const Filename *filename, int type,
522 struct ssh2_userkey *key, char *passphrase);
523
524 void des3_decrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
525 void des3_encrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
526 void des3_decrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
527 unsigned char *blk, int len);
528 void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
529 unsigned char *blk, int len);
530 void aes256_encrypt_pubkey(unsigned char *key, unsigned char *blk,
531 int len);
532 void aes256_decrypt_pubkey(unsigned char *key, unsigned char *blk,
533 int len);
534
535 void des_encrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
536 void des_decrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
537
538 /*
539 * For progress updates in the key generation utility.
540 */
541 #define PROGFN_INITIALISE 1
542 #define PROGFN_LIN_PHASE 2
543 #define PROGFN_EXP_PHASE 3
544 #define PROGFN_PHASE_EXTENT 4
545 #define PROGFN_READY 5
546 #define PROGFN_PROGRESS 6
547 typedef void (*progfn_t) (void *param, int action, int phase, int progress);
548
549 int rsa_generate(struct RSAKey *key, int bits, progfn_t pfn,
550 void *pfnparam);
551 int dsa_generate(struct dss_key *key, int bits, progfn_t pfn,
552 void *pfnparam);
553 Bignum primegen(int bits, int modulus, int residue, Bignum factor,
554 int phase, progfn_t pfn, void *pfnparam, unsigned firstbits);
555 void invent_firstbits(unsigned *one, unsigned *two);
556
557
558 /*
559 * zlib compression.
560 */
561 void *zlib_compress_init(void);
562 void zlib_compress_cleanup(void *);
563 void *zlib_decompress_init(void);
564 void zlib_decompress_cleanup(void *);
565 int zlib_compress_block(void *, unsigned char *block, int len,
566 unsigned char **outblock, int *outlen);
567 int zlib_decompress_block(void *, unsigned char *block, int len,
568 unsigned char **outblock, int *outlen);
569
570 /*
571 * SSH-1 agent messages.
572 */
573 #define SSH1_AGENTC_REQUEST_RSA_IDENTITIES 1
574 #define SSH1_AGENT_RSA_IDENTITIES_ANSWER 2
575 #define SSH1_AGENTC_RSA_CHALLENGE 3
576 #define SSH1_AGENT_RSA_RESPONSE 4
577 #define SSH1_AGENTC_ADD_RSA_IDENTITY 7
578 #define SSH1_AGENTC_REMOVE_RSA_IDENTITY 8
579 #define SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES 9 /* openssh private? */
580
581 /*
582 * Messages common to SSH-1 and OpenSSH's SSH-2.
583 */
584 #define SSH_AGENT_FAILURE 5
585 #define SSH_AGENT_SUCCESS 6
586
587 /*
588 * OpenSSH's SSH-2 agent messages.
589 */
590 #define SSH2_AGENTC_REQUEST_IDENTITIES 11
591 #define SSH2_AGENT_IDENTITIES_ANSWER 12
592 #define SSH2_AGENTC_SIGN_REQUEST 13
593 #define SSH2_AGENT_SIGN_RESPONSE 14
594 #define SSH2_AGENTC_ADD_IDENTITY 17
595 #define SSH2_AGENTC_REMOVE_IDENTITY 18
596 #define SSH2_AGENTC_REMOVE_ALL_IDENTITIES 19
597
598 /*
599 * Need this to warn about support for the original SSH-2 keyfile
600 * format.
601 */
602 void old_keyfile_warning(void);