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 "network.h"
   6 #include "int64.h"
   7 #include "misc.h"
   8
   9 struct ssh_channel;
  10
  11 extern void sshfwd_close(struct ssh_channel *c);
  12 extern int sshfwd_write(struct ssh_channel *c, char *, int);
  13 extern void sshfwd_unthrottle(struct ssh_channel *c, int bufsize);
  14
  15 /*
  16  * Useful thing.
  17  */
  18 #ifndef lenof
  19 #define lenof(x) ( (sizeof((x))) / (sizeof(*(x))))
  20 #endif
  21
  22 #define SSH_CIPHER_IDEA         1
  23 #define SSH_CIPHER_DES          2
  24 #define SSH_CIPHER_3DES         3
  25 #define SSH_CIPHER_BLOWFISH     6
  26
  27 #ifdef MSCRYPTOAPI
  28 #define APIEXTRA 8
  29 #else
  30 #define APIEXTRA 0
  31 #endif
  32
  33 #ifndef BIGNUM_INTERNAL
  34 typedef void *Bignum;
  35 #endif
  36
  37 struct RSAKey {
  38     int bits;
  39     int bytes;
  40 #ifdef MSCRYPTOAPI
  41     unsigned long exponent;
  42     unsigned char *modulus;
  43 #else
  44     Bignum modulus;
  45     Bignum exponent;
  46     Bignum private_exponent;
  47     Bignum p;
  48     Bignum q;
  49     Bignum iqmp;
  50 #endif
  51     char *comment;
  52 };
  53
  54 struct dss_key {
  55     Bignum p, q, g, y, x;
  56 };
  57
  58 int makekey(unsigned char *data, int len, struct RSAKey *result,
  59             unsigned char **keystr, int order);
  60 int makeprivate(unsigned char *data, int len, struct RSAKey *result);
  61 int rsaencrypt(unsigned char *data, int length, struct RSAKey *key);
  62 Bignum rsadecrypt(Bignum input, struct RSAKey *key);
  63 void rsasign(unsigned char *data, int length, struct RSAKey *key);
  64 void rsasanitise(struct RSAKey *key);
  65 int rsastr_len(struct RSAKey *key);
  66 void rsastr_fmt(char *str, struct RSAKey *key);
  67 void rsa_fingerprint(char *str, int len, struct RSAKey *key);
  68 int rsa_verify(struct RSAKey *key);
  69 unsigned char *rsa_public_blob(struct RSAKey *key, int *len);
  70 int rsa_public_blob_len(void *data, int maxlen);
  71 void freersakey(struct RSAKey *key);
  72
  73 typedef unsigned int word32;
  74 typedef unsigned int uint32;
  75
  76 unsigned long crc32_compute(const void *s, size_t len);
  77 unsigned long crc32_update(unsigned long crc_input, const void *s, size_t len);
  78
  79 /* SSH CRC compensation attack detector */
  80 void *crcda_make_context(void);
  81 void crcda_free_context(void *handle);
  82 int detect_attack(void *handle, unsigned char *buf, uint32 len,
  83                   unsigned char *IV);
  84
  85 typedef struct {
  86     uint32 h[4];
  87 } MD5_Core_State;
  88
  89 struct MD5Context {
  90 #ifdef MSCRYPTOAPI
  91     unsigned long hHash;
  92 #else
  93     MD5_Core_State core;
  94     unsigned char block[64];
  95     int blkused;
  96     uint32 lenhi, lenlo;
  97 #endif
  98 };
  99
 100 void MD5Init(struct MD5Context *context);
 101 void MD5Update(struct MD5Context *context, unsigned char const *buf,
 102                unsigned len);
 103 void MD5Final(unsigned char digest[16], struct MD5Context *context);
 104 void MD5Simple(void const *p, unsigned len, unsigned char output[16]);
 105
 106 void *hmacmd5_make_context(void);
 107 void hmacmd5_free_context(void *handle);
 108 void hmacmd5_key(void *handle, void const *key, int len);
 109 void hmacmd5_do_hmac(void *handle, unsigned char const *blk, int len,
 110                      unsigned char *hmac);
 111
 112 typedef struct {
 113     uint32 h[5];
 114     unsigned char block[64];
 115     int blkused;
 116     uint32 lenhi, lenlo;
 117 } SHA_State;
 118 void SHA_Init(SHA_State * s);
 119 void SHA_Bytes(SHA_State * s, void *p, int len);
 120 void SHA_Final(SHA_State * s, unsigned char *output);
 121 void SHA_Simple(void *p, int len, unsigned char *output);
 122
 123 void hmac_sha1_simple(void *key, int keylen, void *data, int datalen,
 124                       unsigned char *output);
 125 typedef struct {
 126     uint32 h[8];
 127     unsigned char block[64];
 128     int blkused;
 129     uint32 lenhi, lenlo;
 130 } SHA256_State;
 131 void SHA256_Init(SHA256_State * s);
 132 void SHA256_Bytes(SHA256_State * s, const void *p, int len);
 133 void SHA256_Final(SHA256_State * s, unsigned char *output);
 134 void SHA256_Simple(const void *p, int len, unsigned char *output);
 135
 136 typedef struct {
 137     uint64 h[8];
 138     unsigned char block[128];
 139     int blkused;
 140     uint32 len[4];
 141 } SHA512_State;
 142 void SHA512_Init(SHA512_State * s);
 143 void SHA512_Bytes(SHA512_State * s, const void *p, int len);
 144 void SHA512_Final(SHA512_State * s, unsigned char *output);
 145 void SHA512_Simple(const void *p, int len, unsigned char *output);
 146
 147 struct ssh_cipher {
 148     void *(*make_context)(void);
 149     void (*free_context)(void *);
 150     void (*sesskey) (void *, unsigned char *key);       /* for SSH-1 */
 151     void (*encrypt) (void *, unsigned char *blk, int len);
 152     void (*decrypt) (void *, unsigned char *blk, int len);
 153     int blksize;
 154     char *text_name;
 155 };
 156
 157 struct ssh2_cipher {
 158     void *(*make_context)(void);
 159     void (*free_context)(void *);
 160     void (*setiv) (void *, unsigned char *key); /* for SSH-2 */
 161     void (*setkey) (void *, unsigned char *key);/* for SSH-2 */
 162     void (*encrypt) (void *, unsigned char *blk, int len);
 163     void (*decrypt) (void *, unsigned char *blk, int len);
 164     char *name;
 165     int blksize;
 166     int keylen;
 167     unsigned int flags;
 168 #define SSH_CIPHER_IS_CBC       1
 169     char *text_name;
 170 };
 171
 172 struct ssh2_ciphers {
 173     int nciphers;
 174     const struct ssh2_cipher *const *list;
 175 };
 176
 177 struct ssh_mac {
 178     void *(*make_context)(void);
 179     void (*free_context)(void *);
 180     void (*setkey) (void *, unsigned char *key);
 181     void (*generate) (void *, unsigned char *blk, int len, unsigned long seq);
 182     int (*verify) (void *, unsigned char *blk, int len, unsigned long seq);
 183     char *name;
 184     int len;
 185     char *text_name;
 186 };
 187
 188 struct ssh_hash {
 189     void *(*init)(void); /* also allocates context */
 190     void (*bytes)(void *, void *, int);
 191     void (*final)(void *, unsigned char *); /* also frees context */
 192     int hlen; /* output length in bytes */
 193     char *text_name;
 194 };
 195
 196 struct ssh_kex {
 197     /*
 198      * Plugging in another KEX algorithm requires structural chaos,
 199      * so it's hard to abstract them into nice little structures
 200      * like this. Fortunately, all our KEXes are basically
 201      * Diffie-Hellman at the moment, so in this structure I simply
 202      * parametrise the DH exchange a bit.
 203      */
 204     char *name, *groupname;
 205     const unsigned char *pdata, *gdata;/* NULL means use group exchange */
 206     int plen, glen;
 207     const struct ssh_hash *hash;
 208 };
 209
 210 struct ssh_kexes {
 211     int nkexes;
 212     const struct ssh_kex *const *list;
 213 };
 214
 215 struct ssh_signkey {
 216     void *(*newkey) (char *data, int len);
 217     void (*freekey) (void *key);
 218     char *(*fmtkey) (void *key);
 219     unsigned char *(*public_blob) (void *key, int *len);
 220     unsigned char *(*private_blob) (void *key, int *len);
 221     void *(*createkey) (unsigned char *pub_blob, int pub_len,
 222                         unsigned char *priv_blob, int priv_len);
 223     void *(*openssh_createkey) (unsigned char **blob, int *len);
 224     int (*openssh_fmtkey) (void *key, unsigned char *blob, int len);
 225     int (*pubkey_bits) (void *blob, int len);
 226     char *(*fingerprint) (void *key);
 227     int (*verifysig) (void *key, char *sig, int siglen,
 228                       char *data, int datalen);
 229     unsigned char *(*sign) (void *key, char *data, int datalen,
 230                             int *siglen);
 231     char *name;
 232     char *keytype;                     /* for host key cache */
 233 };
 234
 235 struct ssh_compress {
 236     char *name;
 237     void *(*compress_init) (void);
 238     void (*compress_cleanup) (void *);
 239     int (*compress) (void *, unsigned char *block, int len,
 240                      unsigned char **outblock, int *outlen);
 241     void *(*decompress_init) (void);
 242     void (*decompress_cleanup) (void *);
 243     int (*decompress) (void *, unsigned char *block, int len,
 244                        unsigned char **outblock, int *outlen);
 245     int (*disable_compression) (void *);
 246     char *text_name;
 247 };
 248
 249 struct ssh2_userkey {
 250     const struct ssh_signkey *alg;     /* the key algorithm */
 251     void *data;                        /* the key data */
 252     char *comment;                     /* the key comment */
 253 };
 254
 255 /* The maximum length of any hash algorithm used in kex. (bytes) */
 256 #define SSH2_KEX_MAX_HASH_LEN (32) /* SHA-256 */
 257
 258 extern const struct ssh_cipher ssh_3des;
 259 extern const struct ssh_cipher ssh_des;
 260 extern const struct ssh_cipher ssh_blowfish_ssh1;
 261 extern const struct ssh2_ciphers ssh2_3des;
 262 extern const struct ssh2_ciphers ssh2_des;
 263 extern const struct ssh2_ciphers ssh2_aes;
 264 extern const struct ssh2_ciphers ssh2_blowfish;
 265 extern const struct ssh2_ciphers ssh2_arcfour;
 266 extern const struct ssh_hash ssh_sha1;
 267 extern const struct ssh_hash ssh_sha256;
 268 extern const struct ssh_kexes ssh_diffiehellman_group1;
 269 extern const struct ssh_kexes ssh_diffiehellman_group14;
 270 extern const struct ssh_kexes ssh_diffiehellman_gex;
 271 extern const struct ssh_signkey ssh_dss;
 272 extern const struct ssh_signkey ssh_rsa;
 273 extern const struct ssh_mac ssh_hmac_md5;
 274 extern const struct ssh_mac ssh_hmac_sha1;
 275 extern const struct ssh_mac ssh_hmac_sha1_buggy;
 276 extern const struct ssh_mac ssh_hmac_sha1_96;
 277 extern const struct ssh_mac ssh_hmac_sha1_96_buggy;
 278
 279
 280 /*
 281  * PuTTY version number formatted as an SSH version string.
 282  */
 283 extern char sshver[];
 284
 285 /*
 286  * Gross hack: pscp will try to start SFTP but fall back to scp1 if
 287  * that fails. This variable is the means by which scp.c can reach
 288  * into the SSH code and find out which one it got.
 289  */
 290 extern int ssh_fallback_cmd(void *handle);
 291
 292 #ifndef MSCRYPTOAPI
 293 void SHATransform(word32 * digest, word32 * data);
 294 #endif
 295
 296 int random_byte(void);
 297 void random_add_noise(void *noise, int length);
 298 void random_add_heavynoise(void *noise, int length);
 299
 300 void logevent(void *, const char *);
 301
 302 /* Allocate and register a new channel for port forwarding */
 303 void *new_sock_channel(void *handle, Socket s);
 304 void ssh_send_port_open(void *channel, char *hostname, int port, char *org);
 305
 306 /* Exports from portfwd.c */
 307 extern const char *pfd_newconnect(Socket * s, char *hostname, int port,
 308                                   void *c, const Config *cfg,
 309                                   int addressfamily);
 310 /* desthost == NULL indicates dynamic (SOCKS) port forwarding */
 311 extern const char *pfd_addforward(char *desthost, int destport, char *srcaddr,
 312                                   int port, void *backhandle,
 313                                   const Config *cfg, void **sockdata,
 314                                   int address_family);
 315 extern void pfd_close(Socket s);
 316 extern void pfd_terminate(void *sockdata);
 317 extern int pfd_send(Socket s, char *data, int len);
 318 extern void pfd_confirm(Socket s);
 319 extern void pfd_unthrottle(Socket s);
 320 extern void pfd_override_throttle(Socket s, int enable);
 321
 322 /* Exports from x11fwd.c */
 323 extern const char *x11_init(Socket *, char *, void *, void *, const char *,
 324                             int, const Config *);
 325 extern void x11_close(Socket);
 326 extern int x11_send(Socket, char *, int);
 327 extern void *x11_invent_auth(char *, int, char *, int, int);
 328 extern void x11_free_auth(void *);
 329 extern void x11_unthrottle(Socket s);
 330 extern void x11_override_throttle(Socket s, int enable);
 331 extern int x11_get_screen_number(char *display);
 332 void x11_get_real_auth(void *authv, char *display);
 333 char *x11_display(const char *display);
 334
 335 /* Platform-dependent X11 functions */
 336 extern void platform_get_x11_auth(char *display, int *proto,
 337                                   unsigned char *data, int *datalen);
 338 extern const char platform_x11_best_transport[];
 339 /* best X11 hostname for this platform if none specified */
 340 SockAddr platform_get_x11_unix_address(int displaynum, char **canonicalname);
 341 /* make up a SockAddr naming the address for displaynum */
 342 char *platform_get_x_display(void);
 343 /* allocated local X display string, if any */
 344
 345 Bignum copybn(Bignum b);
 346 Bignum bn_power_2(int n);
 347 void bn_restore_invariant(Bignum b);
 348 Bignum bignum_from_long(unsigned long n);
 349 void freebn(Bignum b);
 350 Bignum modpow(Bignum base, Bignum exp, Bignum mod);
 351 Bignum modmul(Bignum a, Bignum b, Bignum mod);
 352 void decbn(Bignum n);
 353 extern Bignum Zero, One;
 354 Bignum bignum_from_bytes(const unsigned char *data, int nbytes);
 355 int ssh1_read_bignum(const unsigned char *data, int len, Bignum * result);
 356 int bignum_bitcount(Bignum bn);
 357 int ssh1_bignum_length(Bignum bn);
 358 int ssh2_bignum_length(Bignum bn);
 359 int bignum_byte(Bignum bn, int i);
 360 int bignum_bit(Bignum bn, int i);
 361 void bignum_set_bit(Bignum bn, int i, int value);
 362 int ssh1_write_bignum(void *data, Bignum bn);
 363 Bignum biggcd(Bignum a, Bignum b);
 364 unsigned short bignum_mod_short(Bignum number, unsigned short modulus);
 365 Bignum bignum_add_long(Bignum number, unsigned long addend);
 366 Bignum bigmul(Bignum a, Bignum b);
 367 Bignum bigmuladd(Bignum a, Bignum b, Bignum addend);
 368 Bignum bigdiv(Bignum a, Bignum b);
 369 Bignum bigmod(Bignum a, Bignum b);
 370 Bignum modinv(Bignum number, Bignum modulus);
 371 Bignum bignum_bitmask(Bignum number);
 372 Bignum bignum_rshift(Bignum number, int shift);
 373 int bignum_cmp(Bignum a, Bignum b);
 374 char *bignum_decimal(Bignum x);
 375
 376 #ifdef DEBUG
 377 void diagbn(char *prefix, Bignum md);
 378 #endif
 379
 380 void *dh_setup_group(const struct ssh_kex *kex);
 381 void *dh_setup_gex(Bignum pval, Bignum gval);
 382 void dh_cleanup(void *);
 383 Bignum dh_create_e(void *, int nbits);
 384 Bignum dh_find_K(void *, Bignum f);
 385
 386 int loadrsakey(const Filename *filename, struct RSAKey *key,
 387                char *passphrase, const char **errorstr);
 388 int rsakey_encrypted(const Filename *filename, char **comment);
 389 int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen,
 390                    char **commentptr, const char **errorstr);
 391
 392 int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase);
 393
 394 extern int base64_decode_atom(char *atom, unsigned char *out);
 395 extern int base64_lines(int datalen);
 396 extern void base64_encode_atom(unsigned char *data, int n, char *out);
 397 extern void base64_encode(FILE *fp, unsigned char *data, int datalen, int cpl);
 398
 399 /* ssh2_load_userkey can return this as an error */
 400 extern struct ssh2_userkey ssh2_wrong_passphrase;
 401 #define SSH2_WRONG_PASSPHRASE (&ssh2_wrong_passphrase)
 402
 403 int ssh2_userkey_encrypted(const Filename *filename, char **comment);
 404 struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 405                                        char *passphrase, const char **errorstr);
 406 unsigned char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
 407                                     int *pub_blob_len, char **commentptr,
 408                                     const char **errorstr);
 409 int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key,
 410                       char *passphrase);
 411 const struct ssh_signkey *find_pubkey_alg(const char *name);
 412
 413 enum {
 414     SSH_KEYTYPE_UNOPENABLE,
 415     SSH_KEYTYPE_UNKNOWN,
 416     SSH_KEYTYPE_SSH1, SSH_KEYTYPE_SSH2,
 417     SSH_KEYTYPE_OPENSSH, SSH_KEYTYPE_SSHCOM
 418 };
 419 int key_type(const Filename *filename);
 420 char *key_type_to_str(int type);
 421
 422 int import_possible(int type);
 423 int import_target_type(int type);
 424 int import_encrypted(const Filename *filename, int type, char **comment);
 425 int import_ssh1(const Filename *filename, int type,
 426                 struct RSAKey *key, char *passphrase, const char **errmsg_p);
 427 struct ssh2_userkey *import_ssh2(const Filename *filename, int type,
 428                                  char *passphrase, const char **errmsg_p);
 429 int export_ssh1(const Filename *filename, int type,
 430                 struct RSAKey *key, char *passphrase);
 431 int export_ssh2(const Filename *filename, int type,
 432                 struct ssh2_userkey *key, char *passphrase);
 433
 434 void des3_decrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 435 void des3_encrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 436 void des3_decrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 437                               unsigned char *blk, int len);
 438 void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 439                               unsigned char *blk, int len);
 440 void aes256_encrypt_pubkey(unsigned char *key, unsigned char *blk,
 441                            int len);
 442 void aes256_decrypt_pubkey(unsigned char *key, unsigned char *blk,
 443                            int len);
 444
 445 void des_encrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 446 void des_decrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 447
 448 /*
 449  * For progress updates in the key generation utility.
 450  */
 451 #define PROGFN_INITIALISE 1
 452 #define PROGFN_LIN_PHASE 2
 453 #define PROGFN_EXP_PHASE 3
 454 #define PROGFN_PHASE_EXTENT 4
 455 #define PROGFN_READY 5
 456 #define PROGFN_PROGRESS 6
 457 typedef void (*progfn_t) (void *param, int action, int phase, int progress);
 458
 459 int rsa_generate(struct RSAKey *key, int bits, progfn_t pfn,
 460                  void *pfnparam);
 461 int dsa_generate(struct dss_key *key, int bits, progfn_t pfn,
 462                  void *pfnparam);
 463 Bignum primegen(int bits, int modulus, int residue, Bignum factor,
 464                 int phase, progfn_t pfn, void *pfnparam);
 465
 466
 467 /*
 468  * zlib compression.
 469  */
 470 void *zlib_compress_init(void);
 471 void zlib_compress_cleanup(void *);
 472 void *zlib_decompress_init(void);
 473 void zlib_decompress_cleanup(void *);
 474 int zlib_compress_block(void *, unsigned char *block, int len,
 475                         unsigned char **outblock, int *outlen);
 476 int zlib_decompress_block(void *, unsigned char *block, int len,
 477                           unsigned char **outblock, int *outlen);
 478
 479 /*
 480  * SSH-1 agent messages.
 481  */
 482 #define SSH1_AGENTC_REQUEST_RSA_IDENTITIES    1
 483 #define SSH1_AGENT_RSA_IDENTITIES_ANSWER      2
 484 #define SSH1_AGENTC_RSA_CHALLENGE             3
 485 #define SSH1_AGENT_RSA_RESPONSE               4
 486 #define SSH1_AGENTC_ADD_RSA_IDENTITY          7
 487 #define SSH1_AGENTC_REMOVE_RSA_IDENTITY       8
 488 #define SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES 9 /* openssh private? */
 489
 490 /*
 491  * Messages common to SSH-1 and OpenSSH's SSH-2.
 492  */
 493 #define SSH_AGENT_FAILURE                    5
 494 #define SSH_AGENT_SUCCESS                    6
 495
 496 /*
 497  * OpenSSH's SSH-2 agent messages.
 498  */
 499 #define SSH2_AGENTC_REQUEST_IDENTITIES          11
 500 #define SSH2_AGENT_IDENTITIES_ANSWER            12
 501 #define SSH2_AGENTC_SIGN_REQUEST                13
 502 #define SSH2_AGENT_SIGN_RESPONSE                14
 503 #define SSH2_AGENTC_ADD_IDENTITY                17
 504 #define SSH2_AGENTC_REMOVE_IDENTITY             18
 505 #define SSH2_AGENTC_REMOVE_ALL_IDENTITIES       19
 506
 507 /*
 508  * Need this to warn about support for the original SSH-2 keyfile
 509  * format.
 510  */
 511 void old_keyfile_warning(void);