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