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 /*
  86  * SSH2 RSA key exchange functions
  87  */
  88 struct ssh_hash;
  89 void *ssh_rsakex_newkey(char *data, int len);
  90 void ssh_rsakex_freekey(void *key);
  91 int ssh_rsakex_klen(void *key);
  92 void ssh_rsakex_encrypt(const struct ssh_hash *h, unsigned char *in, int inlen,
  93                         unsigned char *out, int outlen,
  94                         void *key);
  95
  96 typedef struct {
  97     uint32 h[4];
  98 } MD5_Core_State;
  99
 100 struct MD5Context {
 101 #ifdef MSCRYPTOAPI
 102     unsigned long hHash;
 103 #else
 104     MD5_Core_State core;
 105     unsigned char block[64];
 106     int blkused;
 107     uint32 lenhi, lenlo;
 108 #endif
 109 };
 110
 111 void MD5Init(struct MD5Context *context);
 112 void MD5Update(struct MD5Context *context, unsigned char const *buf,
 113                unsigned len);
 114 void MD5Final(unsigned char digest[16], struct MD5Context *context);
 115 void MD5Simple(void const *p, unsigned len, unsigned char output[16]);
 116
 117 void *hmacmd5_make_context(void);
 118 void hmacmd5_free_context(void *handle);
 119 void hmacmd5_key(void *handle, void const *key, int len);
 120 void hmacmd5_do_hmac(void *handle, unsigned char const *blk, int len,
 121                      unsigned char *hmac);
 122
 123 typedef struct {
 124     uint32 h[5];
 125     unsigned char block[64];
 126     int blkused;
 127     uint32 lenhi, lenlo;
 128 } SHA_State;
 129 void SHA_Init(SHA_State * s);
 130 void SHA_Bytes(SHA_State * s, void *p, int len);
 131 void SHA_Final(SHA_State * s, unsigned char *output);
 132 void SHA_Simple(void *p, int len, unsigned char *output);
 133
 134 void hmac_sha1_simple(void *key, int keylen, void *data, int datalen,
 135                       unsigned char *output);
 136 typedef struct {
 137     uint32 h[8];
 138     unsigned char block[64];
 139     int blkused;
 140     uint32 lenhi, lenlo;
 141 } SHA256_State;
 142 void SHA256_Init(SHA256_State * s);
 143 void SHA256_Bytes(SHA256_State * s, const void *p, int len);
 144 void SHA256_Final(SHA256_State * s, unsigned char *output);
 145 void SHA256_Simple(const void *p, int len, unsigned char *output);
 146
 147 typedef struct {
 148     uint64 h[8];
 149     unsigned char block[128];
 150     int blkused;
 151     uint32 len[4];
 152 } SHA512_State;
 153 void SHA512_Init(SHA512_State * s);
 154 void SHA512_Bytes(SHA512_State * s, const void *p, int len);
 155 void SHA512_Final(SHA512_State * s, unsigned char *output);
 156 void SHA512_Simple(const void *p, int len, unsigned char *output);
 157
 158 struct ssh_cipher {
 159     void *(*make_context)(void);
 160     void (*free_context)(void *);
 161     void (*sesskey) (void *, unsigned char *key);       /* for SSH-1 */
 162     void (*encrypt) (void *, unsigned char *blk, int len);
 163     void (*decrypt) (void *, unsigned char *blk, int len);
 164     int blksize;
 165     char *text_name;
 166 };
 167
 168 struct ssh2_cipher {
 169     void *(*make_context)(void);
 170     void (*free_context)(void *);
 171     void (*setiv) (void *, unsigned char *key); /* for SSH-2 */
 172     void (*setkey) (void *, unsigned char *key);/* for SSH-2 */
 173     void (*encrypt) (void *, unsigned char *blk, int len);
 174     void (*decrypt) (void *, unsigned char *blk, int len);
 175     char *name;
 176     int blksize;
 177     int keylen;
 178     unsigned int flags;
 179 #define SSH_CIPHER_IS_CBC       1
 180     char *text_name;
 181 };
 182
 183 struct ssh2_ciphers {
 184     int nciphers;
 185     const struct ssh2_cipher *const *list;
 186 };
 187
 188 struct ssh_mac {
 189     void *(*make_context)(void);
 190     void (*free_context)(void *);
 191     void (*setkey) (void *, unsigned char *key);
 192     void (*generate) (void *, unsigned char *blk, int len, unsigned long seq);
 193     int (*verify) (void *, unsigned char *blk, int len, unsigned long seq);
 194     char *name;
 195     int len;
 196     char *text_name;
 197 };
 198
 199 struct ssh_hash {
 200     void *(*init)(void); /* also allocates context */
 201     void (*bytes)(void *, void *, int);
 202     void (*final)(void *, unsigned char *); /* also frees context */
 203     int hlen; /* output length in bytes */
 204     char *text_name;
 205 };
 206
 207 struct ssh_kex {
 208     char *name, *groupname;
 209     enum { KEXTYPE_DH, KEXTYPE_RSA } main_type;
 210     /* For DH */
 211     const unsigned char *pdata, *gdata; /* NULL means group exchange */
 212     int plen, glen;
 213     const struct ssh_hash *hash;
 214 };
 215
 216 struct ssh_kexes {
 217     int nkexes;
 218     const struct ssh_kex *const *list;
 219 };
 220
 221 struct ssh_signkey {
 222     void *(*newkey) (char *data, int len);
 223     void (*freekey) (void *key);
 224     char *(*fmtkey) (void *key);
 225     unsigned char *(*public_blob) (void *key, int *len);
 226     unsigned char *(*private_blob) (void *key, int *len);
 227     void *(*createkey) (unsigned char *pub_blob, int pub_len,
 228                         unsigned char *priv_blob, int priv_len);
 229     void *(*openssh_createkey) (unsigned char **blob, int *len);
 230     int (*openssh_fmtkey) (void *key, unsigned char *blob, int len);
 231     int (*pubkey_bits) (void *blob, int len);
 232     char *(*fingerprint) (void *key);
 233     int (*verifysig) (void *key, char *sig, int siglen,
 234                       char *data, int datalen);
 235     unsigned char *(*sign) (void *key, char *data, int datalen,
 236                             int *siglen);
 237     char *name;
 238     char *keytype;                     /* for host key cache */
 239 };
 240
 241 struct ssh_compress {
 242     char *name;
 243     void *(*compress_init) (void);
 244     void (*compress_cleanup) (void *);
 245     int (*compress) (void *, unsigned char *block, int len,
 246                      unsigned char **outblock, int *outlen);
 247     void *(*decompress_init) (void);
 248     void (*decompress_cleanup) (void *);
 249     int (*decompress) (void *, unsigned char *block, int len,
 250                        unsigned char **outblock, int *outlen);
 251     int (*disable_compression) (void *);
 252     char *text_name;
 253 };
 254
 255 struct ssh2_userkey {
 256     const struct ssh_signkey *alg;     /* the key algorithm */
 257     void *data;                        /* the key data */
 258     char *comment;                     /* the key comment */
 259 };
 260
 261 /* The maximum length of any hash algorithm used in kex. (bytes) */
 262 #define SSH2_KEX_MAX_HASH_LEN (32) /* SHA-256 */
 263
 264 extern const struct ssh_cipher ssh_3des;
 265 extern const struct ssh_cipher ssh_des;
 266 extern const struct ssh_cipher ssh_blowfish_ssh1;
 267 extern const struct ssh2_ciphers ssh2_3des;
 268 extern const struct ssh2_ciphers ssh2_des;
 269 extern const struct ssh2_ciphers ssh2_aes;
 270 extern const struct ssh2_ciphers ssh2_blowfish;
 271 extern const struct ssh2_ciphers ssh2_arcfour;
 272 extern const struct ssh_hash ssh_sha1;
 273 extern const struct ssh_hash ssh_sha256;
 274 extern const struct ssh_kexes ssh_diffiehellman_group1;
 275 extern const struct ssh_kexes ssh_diffiehellman_group14;
 276 extern const struct ssh_kexes ssh_diffiehellman_gex;
 277 extern const struct ssh_kexes ssh_rsa_kex;
 278 extern const struct ssh_signkey ssh_dss;
 279 extern const struct ssh_signkey ssh_rsa;
 280 extern const struct ssh_mac ssh_hmac_md5;
 281 extern const struct ssh_mac ssh_hmac_sha1;
 282 extern const struct ssh_mac ssh_hmac_sha1_buggy;
 283 extern const struct ssh_mac ssh_hmac_sha1_96;
 284 extern const struct ssh_mac ssh_hmac_sha1_96_buggy;
 285
 286
 287 /*
 288  * PuTTY version number formatted as an SSH version string.
 289  */
 290 extern char sshver[];
 291
 292 /*
 293  * Gross hack: pscp will try to start SFTP but fall back to scp1 if
 294  * that fails. This variable is the means by which scp.c can reach
 295  * into the SSH code and find out which one it got.
 296  */
 297 extern int ssh_fallback_cmd(void *handle);
 298
 299 #ifndef MSCRYPTOAPI
 300 void SHATransform(word32 * digest, word32 * data);
 301 #endif
 302
 303 int random_byte(void);
 304 void random_add_noise(void *noise, int length);
 305 void random_add_heavynoise(void *noise, int length);
 306
 307 void logevent(void *, const char *);
 308
 309 /* Allocate and register a new channel for port forwarding */
 310 void *new_sock_channel(void *handle, Socket s);
 311 void ssh_send_port_open(void *channel, char *hostname, int port, char *org);
 312
 313 /* Exports from portfwd.c */
 314 extern const char *pfd_newconnect(Socket * s, char *hostname, int port,
 315                                   void *c, const Config *cfg,
 316                                   int addressfamily);
 317 /* desthost == NULL indicates dynamic (SOCKS) port forwarding */
 318 extern const char *pfd_addforward(char *desthost, int destport, char *srcaddr,
 319                                   int port, void *backhandle,
 320                                   const Config *cfg, void **sockdata,
 321                                   int address_family);
 322 extern void pfd_close(Socket s);
 323 extern void pfd_terminate(void *sockdata);
 324 extern int pfd_send(Socket s, char *data, int len);
 325 extern void pfd_confirm(Socket s);
 326 extern void pfd_unthrottle(Socket s);
 327 extern void pfd_override_throttle(Socket s, int enable);
 328
 329 /* Exports from x11fwd.c */
 330 extern const char *x11_init(Socket *, char *, void *, void *, const char *,
 331                             int, const Config *);
 332 extern void x11_close(Socket);
 333 extern int x11_send(Socket, char *, int);
 334 extern void *x11_invent_auth(char *, int, char *, int, int);
 335 extern void x11_free_auth(void *);
 336 extern void x11_unthrottle(Socket s);
 337 extern void x11_override_throttle(Socket s, int enable);
 338 extern int x11_get_screen_number(char *display);
 339 void x11_get_real_auth(void *authv, char *display);
 340 char *x11_display(const char *display);
 341
 342 /* Platform-dependent X11 functions */
 343 extern void platform_get_x11_auth(char *display, int *proto,
 344                                   unsigned char *data, int *datalen);
 345 extern const char platform_x11_best_transport[];
 346 /* best X11 hostname for this platform if none specified */
 347 SockAddr platform_get_x11_unix_address(const char *display, int displaynum,
 348                                        char **canonicalname);
 349 /* make up a SockAddr naming the address for displaynum */
 350 char *platform_get_x_display(void);
 351 /* allocated local X display string, if any */
 352
 353 Bignum copybn(Bignum b);
 354 Bignum bn_power_2(int n);
 355 void bn_restore_invariant(Bignum b);
 356 Bignum bignum_from_long(unsigned long n);
 357 void freebn(Bignum b);
 358 Bignum modpow(Bignum base, Bignum exp, Bignum mod);
 359 Bignum modmul(Bignum a, Bignum b, Bignum mod);
 360 void decbn(Bignum n);
 361 extern Bignum Zero, One;
 362 Bignum bignum_from_bytes(const unsigned char *data, int nbytes);
 363 int ssh1_read_bignum(const unsigned char *data, int len, Bignum * result);
 364 int bignum_bitcount(Bignum bn);
 365 int ssh1_bignum_length(Bignum bn);
 366 int ssh2_bignum_length(Bignum bn);
 367 int bignum_byte(Bignum bn, int i);
 368 int bignum_bit(Bignum bn, int i);
 369 void bignum_set_bit(Bignum bn, int i, int value);
 370 int ssh1_write_bignum(void *data, Bignum bn);
 371 Bignum biggcd(Bignum a, Bignum b);
 372 unsigned short bignum_mod_short(Bignum number, unsigned short modulus);
 373 Bignum bignum_add_long(Bignum number, unsigned long addend);
 374 Bignum bigmul(Bignum a, Bignum b);
 375 Bignum bigmuladd(Bignum a, Bignum b, Bignum addend);
 376 Bignum bigdiv(Bignum a, Bignum b);
 377 Bignum bigmod(Bignum a, Bignum b);
 378 Bignum modinv(Bignum number, Bignum modulus);
 379 Bignum bignum_bitmask(Bignum number);
 380 Bignum bignum_rshift(Bignum number, int shift);
 381 int bignum_cmp(Bignum a, Bignum b);
 382 char *bignum_decimal(Bignum x);
 383
 384 #ifdef DEBUG
 385 void diagbn(char *prefix, Bignum md);
 386 #endif
 387
 388 void *dh_setup_group(const struct ssh_kex *kex);
 389 void *dh_setup_gex(Bignum pval, Bignum gval);
 390 void dh_cleanup(void *);
 391 Bignum dh_create_e(void *, int nbits);
 392 Bignum dh_find_K(void *, Bignum f);
 393
 394 int loadrsakey(const Filename *filename, struct RSAKey *key,
 395                char *passphrase, const char **errorstr);
 396 int rsakey_encrypted(const Filename *filename, char **comment);
 397 int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen,
 398                    char **commentptr, const char **errorstr);
 399
 400 int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase);
 401
 402 extern int base64_decode_atom(char *atom, unsigned char *out);
 403 extern int base64_lines(int datalen);
 404 extern void base64_encode_atom(unsigned char *data, int n, char *out);
 405 extern void base64_encode(FILE *fp, unsigned char *data, int datalen, int cpl);
 406
 407 /* ssh2_load_userkey can return this as an error */
 408 extern struct ssh2_userkey ssh2_wrong_passphrase;
 409 #define SSH2_WRONG_PASSPHRASE (&ssh2_wrong_passphrase)
 410
 411 int ssh2_userkey_encrypted(const Filename *filename, char **comment);
 412 struct ssh2_userkey *ssh2_load_userkey(const Filename *filename,
 413                                        char *passphrase, const char **errorstr);
 414 unsigned char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm,
 415                                     int *pub_blob_len, char **commentptr,
 416                                     const char **errorstr);
 417 int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key,
 418                       char *passphrase);
 419 const struct ssh_signkey *find_pubkey_alg(const char *name);
 420
 421 enum {
 422     SSH_KEYTYPE_UNOPENABLE,
 423     SSH_KEYTYPE_UNKNOWN,
 424     SSH_KEYTYPE_SSH1, SSH_KEYTYPE_SSH2,
 425     SSH_KEYTYPE_OPENSSH, SSH_KEYTYPE_SSHCOM
 426 };
 427 int key_type(const Filename *filename);
 428 char *key_type_to_str(int type);
 429
 430 int import_possible(int type);
 431 int import_target_type(int type);
 432 int import_encrypted(const Filename *filename, int type, char **comment);
 433 int import_ssh1(const Filename *filename, int type,
 434                 struct RSAKey *key, char *passphrase, const char **errmsg_p);
 435 struct ssh2_userkey *import_ssh2(const Filename *filename, int type,
 436                                  char *passphrase, const char **errmsg_p);
 437 int export_ssh1(const Filename *filename, int type,
 438                 struct RSAKey *key, char *passphrase);
 439 int export_ssh2(const Filename *filename, int type,
 440                 struct ssh2_userkey *key, char *passphrase);
 441
 442 void des3_decrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 443 void des3_encrypt_pubkey(unsigned char *key, unsigned char *blk, int len);
 444 void des3_decrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 445                               unsigned char *blk, int len);
 446 void des3_encrypt_pubkey_ossh(unsigned char *key, unsigned char *iv,
 447                               unsigned char *blk, int len);
 448 void aes256_encrypt_pubkey(unsigned char *key, unsigned char *blk,
 449                            int len);
 450 void aes256_decrypt_pubkey(unsigned char *key, unsigned char *blk,
 451                            int len);
 452
 453 void des_encrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 454 void des_decrypt_xdmauth(unsigned char *key, unsigned char *blk, int len);
 455
 456 /*
 457  * For progress updates in the key generation utility.
 458  */
 459 #define PROGFN_INITIALISE 1
 460 #define PROGFN_LIN_PHASE 2
 461 #define PROGFN_EXP_PHASE 3
 462 #define PROGFN_PHASE_EXTENT 4
 463 #define PROGFN_READY 5
 464 #define PROGFN_PROGRESS 6
 465 typedef void (*progfn_t) (void *param, int action, int phase, int progress);
 466
 467 int rsa_generate(struct RSAKey *key, int bits, progfn_t pfn,
 468                  void *pfnparam);
 469 int dsa_generate(struct dss_key *key, int bits, progfn_t pfn,
 470                  void *pfnparam);
 471 Bignum primegen(int bits, int modulus, int residue, Bignum factor,
 472                 int phase, progfn_t pfn, void *pfnparam);
 473
 474
 475 /*
 476  * zlib compression.
 477  */
 478 void *zlib_compress_init(void);
 479 void zlib_compress_cleanup(void *);
 480 void *zlib_decompress_init(void);
 481 void zlib_decompress_cleanup(void *);
 482 int zlib_compress_block(void *, unsigned char *block, int len,
 483                         unsigned char **outblock, int *outlen);
 484 int zlib_decompress_block(void *, unsigned char *block, int len,
 485                           unsigned char **outblock, int *outlen);
 486
 487 /*
 488  * SSH-1 agent messages.
 489  */
 490 #define SSH1_AGENTC_REQUEST_RSA_IDENTITIES    1
 491 #define SSH1_AGENT_RSA_IDENTITIES_ANSWER      2
 492 #define SSH1_AGENTC_RSA_CHALLENGE             3
 493 #define SSH1_AGENT_RSA_RESPONSE               4
 494 #define SSH1_AGENTC_ADD_RSA_IDENTITY          7
 495 #define SSH1_AGENTC_REMOVE_RSA_IDENTITY       8
 496 #define SSH1_AGENTC_REMOVE_ALL_RSA_IDENTITIES 9 /* openssh private? */
 497
 498 /*
 499  * Messages common to SSH-1 and OpenSSH's SSH-2.
 500  */
 501 #define SSH_AGENT_FAILURE                    5
 502 #define SSH_AGENT_SUCCESS                    6
 503
 504 /*
 505  * OpenSSH's SSH-2 agent messages.
 506  */
 507 #define SSH2_AGENTC_REQUEST_IDENTITIES          11
 508 #define SSH2_AGENT_IDENTITIES_ANSWER            12
 509 #define SSH2_AGENTC_SIGN_REQUEST                13
 510 #define SSH2_AGENT_SIGN_RESPONSE                14
 511 #define SSH2_AGENTC_ADD_IDENTITY                17
 512 #define SSH2_AGENTC_REMOVE_IDENTITY             18
 513 #define SSH2_AGENTC_REMOVE_ALL_IDENTITIES       19
 514
 515 /*
 516  * Need this to warn about support for the original SSH-2 keyfile
 517  * format.
 518  */
 519 void old_keyfile_warning(void);