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
 126 typedef struct {
 127     uint64 h[8];
 128     unsigned char block[128];
 129     int blkused;
 130     uint32 len[4];
 131 } SHA512_State;
 132 void SHA512_Init(SHA512_State * s);
 133 void SHA512_Bytes(SHA512_State * s, const void *p, int len);
 134 void SHA512_Final(SHA512_State * s, unsigned char *output);
 135 void SHA512_Simple(const void *p, int len, unsigned char *output);
 136
 137 struct ssh_cipher {
 138     void *(*make_context)(void);
 139     void (*free_context)(void *);
 140     void (*sesskey) (void *, unsigned char *key);       /* for SSH-1 */
 141     void (*encrypt) (void *, unsigned char *blk, int len);
 142     void (*decrypt) (void *, unsigned char *blk, int len);
 143     int blksize;
 144     char *text_name;
 145 };
 146
 147 struct ssh2_cipher {
 148     void *(*make_context)(void);
 149     void (*free_context)(void *);
 150     void (*setiv) (void *, unsigned char *key); /* for SSH-2 */
 151     void (*setkey) (void *, unsigned char *key);/* for SSH-2 */
 152     void (*encrypt) (void *, unsigned char *blk, int len);
 153     void (*decrypt) (void *, unsigned char *blk, int len);
 154     char *name;
 155     int blksize;
 156     int keylen;
 157     unsigned int flags;
 158 #define SSH_CIPHER_IS_CBC       1
 159     char *text_name;
 160 };
 161
 162 struct ssh2_ciphers {
 163     int nciphers;
 164     const struct ssh2_cipher *const *list;
 165 };
 166
 167 struct ssh_mac {
 168     void *(*make_context)(void);
 169     void (*free_context)(void *);
 170     void (*setkey) (void *, unsigned char *key);
 171     void (*generate) (void *, unsigned char *blk, int len, unsigned long seq);
 172     int (*verify) (void *, unsigned char *blk, int len, unsigned long seq);
 173     char *name;
 174     int len;
 175     char *text_name;
 176 };
 177
 178 struct ssh_hash {
 179     void *(*init)(void); /* also allocates context */
 180     void (*bytes)(void *, void *, int);
 181     void (*final)(void *, unsigned char *); /* also frees context */
 182     int hlen; /* output length in bytes */
 183 };
 184
 185 struct ssh_kex {
 186     /*
 187      * Plugging in another KEX algorithm requires structural chaos,
 188      * so it's hard to abstract them into nice little structures
 189      * like this. Fortunately, all our KEXes are basically
 190      * Diffie-Hellman at the moment, so in this structure I simply
 191      * parametrise the DH exchange a bit.
 192      */
 193     char *name, *groupname;
 194     const unsigned char *pdata, *gdata;/* NULL means use group exchange */
 195     int plen, glen;
 196     const struct ssh_hash *hash;
 197 };
 198
 199 struct ssh_signkey {
 200     void *(*newkey) (char *data, int len);
 201     void (*freekey) (void *key);
 202     char *(*fmtkey) (void *key);
 203     unsigned char *(*public_blob) (void *key, int *len);
 204     unsigned char *(*private_blob) (void *key, int *len);
 205     void *(*createkey) (unsigned char *pub_blob, int pub_len,
 206                         unsigned char *priv_blob, int priv_len);
 207     void *(*openssh_createkey) (unsigned char **blob, int *len);
 208     int (*openssh_fmtkey) (void *key, unsigned char *blob, int len);
 209     int (*pubkey_bits) (void *blob, int len);
 210     char *(*fingerprint) (void *key);
 211     int (*verifysig) (void *key, char *sig, int siglen,
 212                       char *data, int datalen);
 213     unsigned char *(*sign) (void *key, char *data, int datalen,
 214                             int *siglen);
 215     char *name;
 216     char *keytype;                     /* for host key cache */
 217 };
 218
 219 struct ssh_compress {
 220     char *name;
 221     void *(*compress_init) (void);
 222     void (*compress_cleanup) (void *);
 223     int (*compress) (void *, unsigned char *block, int len,
 224                      unsigned char **outblock, int *outlen);
 225     void *(*decompress_init) (void);
 226     void (*decompress_cleanup) (void *);
 227     int (*decompress) (void *, unsigned char *block, int len,
 228                        unsigned char **outblock, int *outlen);
 229     int (*disable_compression) (void *);
 230     char *text_name;
 231 };
 232
 233 struct ssh2_userkey {
 234     const struct ssh_signkey *alg;     /* the key algorithm */
 235     void *data;                        /* the key data */
 236     char *comment;                     /* the key comment */
 237 };
 238
 239 extern const struct ssh_cipher ssh_3des;
 240 extern const struct ssh_cipher ssh_des;
 241 extern const struct ssh_cipher ssh_blowfish_ssh1;
 242 extern const struct ssh2_ciphers ssh2_3des;
 243 extern const struct ssh2_ciphers ssh2_des;
 244 extern const struct ssh2_ciphers ssh2_aes;
 245 extern const struct ssh2_ciphers ssh2_blowfish;
 246 extern const struct ssh2_ciphers ssh2_arcfour;
 247 extern const struct ssh_hash ssh_sha1;
 248 extern const struct ssh_kex ssh_diffiehellman_group1;
 249 extern const struct ssh_kex ssh_diffiehellman_group14;
 250 extern const struct ssh_kex ssh_diffiehellman_gex;
 251 extern const struct ssh_signkey ssh_dss;
 252 extern const struct ssh_signkey ssh_rsa;
 253 extern const struct ssh_mac ssh_hmac_md5;
 254 extern const struct ssh_mac ssh_hmac_sha1;
 255 extern const struct ssh_mac ssh_hmac_sha1_buggy;
 256
 257
 258 /*
 259  * PuTTY version number formatted as an SSH version string.
 260  */
 261 extern char sshver[];
 262
 263 /*
 264  * Gross hack: pscp will try to start SFTP but fall back to scp1 if
 265  * that fails. This variable is the means by which scp.c can reach
 266  * into the SSH code and find out which one it got.
 267  */
 268 extern int ssh_fallback_cmd(void *handle);
 269
 270 #ifndef MSCRYPTOAPI
 271 void SHATransform(word32 * digest, word32 * data);
 272 #endif
 273
 274 int random_byte(void);
 275 void random_add_noise(void *noise, int length);
 276 void random_add_heavynoise(void *noise, int length);
 277
 278 void logevent(void *, const char *);
 279
 280 /* Allocate and register a new channel for port forwarding */
 281 void *new_sock_channel(void *handle, Socket s);
 282 void ssh_send_port_open(void *channel, char *hostname, int port, char *org);
 283
 284 /* Exports from portfwd.c */
 285 extern const char *pfd_newconnect(Socket * s, char *hostname, int port,
 286                                   void *c, const Config *cfg,
 287                                   int addressfamily);
 288 /* desthost == NULL indicates dynamic (SOCKS) port forwarding */
 289 extern const char *pfd_addforward(char *desthost, int destport, char *srcaddr,
 290                                   int port, void *backhandle,
 291                                   const Config *cfg, void **sockdata,
 292                                   int address_family);
 293 extern void pfd_close(Socket s);
 294 extern void pfd_terminate(void *sockdata);
 295 extern int pfd_send(Socket s, char *data, int len);
 296 extern void pfd_confirm(Socket s);
 297 extern void pfd_unthrottle(Socket s);
 298 extern void pfd_override_throttle(Socket s, int enable);
 299
 300 /* Exports from x11fwd.c */
 301 extern const char *x11_init(Socket *, char *, void *, void *, const char *,
 302                             int, const Config *);
 303 extern void x11_close(Socket);
 304 extern int x11_send(Socket, char *, int);
 305 extern void *x11_invent_auth(char *, int, char *, int, int);
 306 extern void x11_free_auth(void *);
 307 extern void x11_unthrottle(Socket s);
 308 extern void x11_override_throttle(Socket s, int enable);
 309 extern int x11_get_screen_number(char *display);
 310 void x11_get_real_auth(void *authv, char *display);
 311 char *x11_display(const char *display);
 312
 313 /* Platform-dependent X11 functions */
 314 extern void platform_get_x11_auth(char *display, int *proto,
 315                                   unsigned char *data, int *datalen);
 316 extern const char platform_x11_best_transport[];
 317 /* best X11 hostname for this platform if none specified */
 318 SockAddr platform_get_x11_unix_address(int displaynum, char **canonicalname);
 319 /* make up a SockAddr naming the address for displaynum */
 320 char *platform_get_x_display(void);
 321 /* allocated local X display string, if any */
 322
 323 Bignum copybn(Bignum b);
 324 Bignum bn_power_2(int n);
 325 void bn_restore_invariant(Bignum b);
 326 Bignum bignum_from_long(unsigned long n);
 327 void freebn(Bignum b);
 328 Bignum modpow(Bignum base, Bignum exp, Bignum mod);
 329 Bignum modmul(Bignum a, Bignum b, Bignum mod);
 330 void decbn(Bignum n);
 331 extern Bignum Zero, One;
 332 Bignum bignum_from_bytes(const unsigned char *data, int nbytes);
 333 int ssh1_read_bignum(const unsigned char *data, int len, Bignum * result);
 334 int bignum_bitcount(Bignum bn);
 335 int ssh1_bignum_length(Bignum bn);
 336 int ssh2_bignum_length(Bignum bn);
 337 int bignum_byte(Bignum bn, int i);
 338 int bignum_bit(Bignum bn, int i);
 339 void bignum_set_bit(Bignum bn, int i, int value);
 340 int ssh1_write_bignum(void *data, Bignum bn);
 341 Bignum biggcd(Bignum a, Bignum b);
 342 unsigned short bignum_mod_short(Bignum number, unsigned short modulus);
 343 Bignum bignum_add_long(Bignum number, unsigned long addend);
 344 Bignum bigmul(Bignum a, Bignum b);
 345 Bignum bigmuladd(Bignum a, Bignum b, Bignum addend);
 346 Bignum bigdiv(Bignum a, Bignum b);
 347 Bignum bigmod(Bignum a, Bignum b);
 348 Bignum modinv(Bignum number, Bignum modulus);
 349 Bignum bignum_bitmask(Bignum number);
 350 Bignum bignum_rshift(Bignum number, int shift);
 351 int bignum_cmp(Bignum a, Bignum b);
 352 char *bignum_decimal(Bignum x);
 353
 354 #ifdef DEBUG
 355 void diagbn(char *prefix, Bignum md);
 356 #endif
 357
 358 void *dh_setup_group(const struct ssh_kex *kex);
 359 void *dh_setup_gex(Bignum pval, Bignum gval);
 360 void dh_cleanup(void *);
 361 Bignum dh_create_e(void *, int nbits);
 362 Bignum dh_find_K(void *, Bignum f);
 363
 364 int loadrsakey(const Filename *filename, struct RSAKey *key,
 365                char *passphrase, const char **errorstr);
 366 int rsakey_encrypted(const Filename *filename, char **comment);
 367 int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen,
 368                    const char **errorstr);
 369
 370 int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase);
 371
 372 extern int base64_decode_atom(char *atom, unsigned char *out);
 373 extern int base64_lines(int datalen);
 374 extern void base64_encode_atom(unsigned char *data, int n, char *out);
 375 extern void base64_encode(FILE *fp, unsigned char *data, int datalen, int cpl);
 376
 377 /* ssh2_load_userkey can return this as an error */
 378 extern struct ssh2_userkey ssh2_wrong_passphrase;
 379 #define SSH2_WRONG_PASSPHRASE (&ssh2_wrong_passphrase)
 380
 381 int ssh2_userkey_encrypted(const Filename *filename, char **comment);
 382 struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 383                                        char *passphrase, const char **errorstr);
 384 char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
 385                            int *pub_blob_len, const char **errorstr);
 386 int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key,
 387                       char *passphrase);
 388 const struct ssh_signkey *find_pubkey_alg(const char *name);
 389
 390 enum {
 391     SSH_KEYTYPE_UNOPENABLE,
 392     SSH_KEYTYPE_UNKNOWN,
 393     SSH_KEYTYPE_SSH1, SSH_KEYTYPE_SSH2,
 394     SSH_KEYTYPE_OPENSSH, SSH_KEYTYPE_SSHCOM
 395 };
 396 int key_type(const Filename *filename);
 397 char *key_type_to_str(int type);
 398
 399 int import_possible(int type);
 400 int import_target_type(int type);
 401 int import_encrypted(const Filename *filename, int type, char **comment);
 402 int import_ssh1(const Filename *filename, int type,
 403                 struct RSAKey *key, char *passphrase, const char **errmsg_p);
 404 struct ssh2_userkey *import_ssh2(const Filename *filename, int type,
 405                                  char *passphrase, const char **errmsg_p);
 406 int export_ssh1(const Filename *filename, int type,
 407                 struct RSAKey *key, char *passphrase);
 408 int export_ssh2(const Filename *filename, int type,
 409                 struct ssh2_userkey *key, char *passphrase);
 410
 411 void des3_decrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 412 void des3_encrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 413 void des3_decrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 414                               unsigned char *blk, int len);
 415 void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 416                               unsigned char *blk, int len);
 417 void aes256_encrypt_pubkey(unsigned char *key, unsigned char *blk,
 418                            int len);
 419 void aes256_decrypt_pubkey(unsigned char *key, unsigned char *blk,
 420                            int len);
 421
 422 void des_encrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 423 void des_decrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 424
 425 /*
 426  * For progress updates in the key generation utility.
 427  */
 428 #define PROGFN_INITIALISE 1
 429 #define PROGFN_LIN_PHASE 2
 430 #define PROGFN_EXP_PHASE 3
 431 #define PROGFN_PHASE_EXTENT 4
 432 #define PROGFN_READY 5
 433 #define PROGFN_PROGRESS 6
 434 typedef void (*progfn_t) (void *param, int action, int phase, int progress);
 435
 436 int rsa_generate(struct RSAKey *key, int bits, progfn_t pfn,
 437                  void *pfnparam);
 438 int dsa_generate(struct dss_key *key, int bits, progfn_t pfn,
 439                  void *pfnparam);
 440 Bignum primegen(int bits, int modulus, int residue, Bignum factor,
 441                 int phase, progfn_t pfn, void *pfnparam);
 442
 443
 444 /*
 445  * zlib compression.
 446  */
 447 void *zlib_compress_init(void);
 448 void zlib_compress_cleanup(void *);
 449 void *zlib_decompress_init(void);
 450 void zlib_decompress_cleanup(void *);
 451 int zlib_compress_block(void *, unsigned char *block, int len,
 452                         unsigned char **outblock, int *outlen);
 453 int zlib_decompress_block(void *, unsigned char *block, int len,
 454                           unsigned char **outblock, int *outlen);
 455
 456 /*
 457  * SSH-1 agent messages.
 458  */
 459 #define SSH1_AGENTC_REQUEST_RSA_IDENTITIES    1
 460 #define SSH1_AGENT_RSA_IDENTITIES_ANSWER      2
 461 #define SSH1_AGENTC_RSA_CHALLENGE             3
 462 #define SSH1_AGENT_RSA_RESPONSE               4
 463 #define SSH1_AGENTC_ADD_RSA_IDENTITY          7
 464 #define SSH1_AGENTC_REMOVE_RSA_IDENTITY       8
 465 #define SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES 9 /* openssh private? */
 466
 467 /*
 468  * Messages common to SSH-1 and OpenSSH's SSH-2.
 469  */
 470 #define SSH_AGENT_FAILURE                    5
 471 #define SSH_AGENT_SUCCESS                    6
 472
 473 /*
 474  * OpenSSH's SSH-2 agent messages.
 475  */
 476 #define SSH2_AGENTC_REQUEST_IDENTITIES          11
 477 #define SSH2_AGENT_IDENTITIES_ANSWER            12
 478 #define SSH2_AGENTC_SIGN_REQUEST                13
 479 #define SSH2_AGENT_SIGN_RESPONSE                14
 480 #define SSH2_AGENTC_ADD_IDENTITY                17
 481 #define SSH2_AGENTC_REMOVE_IDENTITY             18
 482 #define SSH2_AGENTC_REMOVE_ALL_IDENTITIES       19
 483
 484 /*
 485  * Need this to warn about support for the original SSH-2 keyfile
 486  * format.
 487  */
 488 void old_keyfile_warning(void);