X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/5c72ca6161da0e7976245222c412d62ebae2e386..7440fd4419acfc9c784f142fb9dee3e64c9a18c2:/sshpubk.c diff --git a/sshpubk.c b/sshpubk.c index 2d1f5540..dd06ebd5 100644 --- a/sshpubk.c +++ b/sshpubk.c @@ -9,7 +9,9 @@ #include #include +#include "putty.h" #include "ssh.h" +#include "misc.h" #define PUT_32BIT(cp, value) do { \ (cp)[3] = (value); \ @@ -31,8 +33,9 @@ (x)=='+' ? 62 : \ (x)=='/' ? 63 : 0 ) -static int loadrsakey_main(FILE * fp, struct RSAKey *key, - char **commentptr, char *passphrase) +static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only, + char **commentptr, char *passphrase, + const char **error) { unsigned char buf[16384]; unsigned char keybuf[16]; @@ -42,13 +45,18 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, struct MD5Context md5c; char *comment; + *error = NULL; + /* Slurp the whole file (minus the header) into a buffer. */ len = fread(buf, 1, sizeof(buf), fp); fclose(fp); - if (len < 0 || len == sizeof(buf)) + if (len < 0 || len == sizeof(buf)) { + *error = "error reading file"; goto end; /* file too big or not read */ + } i = 0; + *error = "file format error"; /* * A zero byte. (The signature includes a terminating NUL.) @@ -75,12 +83,17 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, if (len - i < 0) goto end; /* overran */ + if (pub_only) { + ret = 1; + goto end; + } + /* Next, the comment field. */ j = GET_32BIT(buf + i); i += 4; if (len - i < j) goto end; - comment = smalloc(j + 1); + comment = snewn(j + 1, char); if (comment) { memcpy(comment, buf + i, j); comment[j] = '\0'; @@ -91,7 +104,9 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, if (key) key->comment = comment; if (!key) { - return ciphertype != 0; + ret = ciphertype != 0; + *error = NULL; + goto end; } /* @@ -99,7 +114,7 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, */ if (ciphertype) { MD5Init(&md5c); - MD5Update(&md5c, passphrase, strlen(passphrase)); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); MD5Final(keybuf, &md5c); des3_decrypt_pubkey(keybuf, buf + i, (len - i + 7) & ~7); memset(keybuf, 0, sizeof(keybuf)); /* burn the evidence */ @@ -112,6 +127,7 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, if (len - i < 4) goto end; if (buf[i] != buf[i + 2] || buf[i + 1] != buf[i + 3]) { + *error = "wrong passphrase"; ret = -1; goto end; } @@ -136,6 +152,7 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, goto end; if (!rsa_verify(key)) { + *error = "rsa_verify failed"; freersakey(key); ret = 0; } else @@ -146,40 +163,51 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, return ret; } -int loadrsakey(char *filename, struct RSAKey *key, char *passphrase) +int loadrsakey(const Filename *filename, struct RSAKey *key, char *passphrase, + const char **errorstr) { FILE *fp; - unsigned char buf[64]; + char buf[64]; + int ret = 0; + const char *error = NULL; - fp = fopen(filename, "rb"); - if (!fp) - return 0; /* doesn't even exist */ + fp = f_open(*filename, "rb"); + if (!fp) { + error = "can't open file"; + goto end; + } /* * Read the first line of the file and see if it's a v1 private * key file. */ if (fgets(buf, sizeof(buf), fp) && !strcmp(buf, rsa_signature)) { - return loadrsakey_main(fp, key, NULL, passphrase); + ret = loadrsakey_main(fp, key, FALSE, NULL, passphrase, &error); + goto end; } /* * Otherwise, we have nothing. Return empty-handed. */ fclose(fp); - return 0; + error = "not an SSH-1 RSA file"; + + end: + if ((ret != 1) && errorstr) + *errorstr = error; + return ret; } /* * See whether an RSA key is encrypted. Return its comment field as * well. */ -int rsakey_encrypted(char *filename, char **comment) +int rsakey_encrypted(const Filename *filename, char **comment) { FILE *fp; - unsigned char buf[64]; + char buf[64]; - fp = fopen(filename, "rb"); + fp = f_open(*filename, "rb"); if (!fp) return 0; /* doesn't even exist */ @@ -188,16 +216,64 @@ int rsakey_encrypted(char *filename, char **comment) * key file. */ if (fgets(buf, sizeof(buf), fp) && !strcmp(buf, rsa_signature)) { - return loadrsakey_main(fp, NULL, comment, NULL); + const char *dummy; + return loadrsakey_main(fp, NULL, FALSE, comment, NULL, &dummy); } fclose(fp); return 0; /* wasn't the right kind of file */ } /* + * Return a malloc'ed chunk of memory containing the public blob of + * an RSA key, as given in the agent protocol (modulus bits, + * exponent, modulus). + */ +int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen, + const char **errorstr) +{ + FILE *fp; + char buf[64]; + struct RSAKey key; + int ret; + const char *error = NULL; + + /* Default return if we fail. */ + *blob = NULL; + *bloblen = 0; + ret = 0; + + fp = f_open(*filename, "rb"); + if (!fp) { + error = "can't open file"; + goto end; + } + + /* + * Read the first line of the file and see if it's a v1 private + * key file. + */ + if (fgets(buf, sizeof(buf), fp) && !strcmp(buf, rsa_signature)) { + memset(&key, 0, sizeof(key)); + if (loadrsakey_main(fp, &key, TRUE, NULL, NULL, &error)) { + *blob = rsa_public_blob(&key, bloblen); + freersakey(&key); + ret = 1; + } + } else { + error = "not an SSH-1 RSA file"; + fclose(fp); + } + + end: + if ((ret != 1) && errorstr) + *errorstr = error; + return ret; +} + +/* * Save an RSA key file. Return nonzero on success. */ -int saversakey(char *filename, struct RSAKey *key, char *passphrase) +int saversakey(const Filename *filename, struct RSAKey *key, char *passphrase) { unsigned char buf[16384]; unsigned char keybuf[16]; @@ -278,7 +354,7 @@ int saversakey(char *filename, struct RSAKey *key, char *passphrase) */ if (passphrase) { MD5Init(&md5c); - MD5Update(&md5c, passphrase, strlen(passphrase)); + MD5Update(&md5c, (unsigned char *)passphrase, strlen(passphrase)); MD5Final(keybuf, &md5c); des3_encrypt_pubkey(keybuf, estart, p - estart); memset(keybuf, 0, sizeof(keybuf)); /* burn the evidence */ @@ -287,7 +363,7 @@ int saversakey(char *filename, struct RSAKey *key, char *passphrase) /* * Done. Write the result to the file. */ - fp = fopen(filename, "wb"); + fp = f_open(*filename, "wb"); if (fp) { int ret = (fwrite(buf, 1, p - buf, fp) == (size_t) (p - buf)); ret = ret && (fclose(fp) == 0); @@ -306,7 +382,7 @@ int saversakey(char *filename, struct RSAKey *key, char *passphrase) * The file is text. Lines are terminated by CRLF, although CR-only * and LF-only are tolerated on input. * - * The first line says "PuTTY-User-Key-File-1: " plus the name of the + * The first line says "PuTTY-User-Key-File-2: " plus the name of the * algorithm ("ssh-dss", "ssh-rsa" etc). * * The next line says "Encryption: " plus an encryption type. @@ -339,27 +415,25 @@ int saversakey(char *filename, struct RSAKey *key, char *passphrase) * And for "ssh-dss", it will be composed of * * mpint x (the private key parameter) - * string hash (20-byte hash of mpints p || q || g) - * - * Finally, there is a line saying _either_ - * - * - "Private-Hash: " plus a hex representation of a SHA-1 hash of - * the plaintext version of the private part, including the - * final padding. - * - * or + * [ string hash 20-byte hash of mpints p || q || g only in old format ] * - * - "Private-MAC: " plus a hex representation of a HMAC-SHA-1 of - * the plaintext version of the private part, including the - * final padding. + * Finally, there is a line saying "Private-MAC: " plus a hex + * representation of a HMAC-SHA-1 of: + * + * string name of algorithm ("ssh-dss", "ssh-rsa") + * string encryption type + * string comment + * string public-blob + * string private-plaintext (the plaintext version of the + * private part, including the final + * padding) * * The key to the MAC is itself a SHA-1 hash of: * * data "putty-private-key-file-mac-key" * data passphrase * - * Encrypted keys should have a MAC, whereas unencrypted ones must - * have a hash. + * (An empty passphrase is used for unencrypted keys.) * * If the key is encrypted, the encryption key is derived from the * passphrase by means of a succession of SHA-1 hashes. Each hash @@ -371,16 +445,15 @@ int saversakey(char *filename, struct RSAKey *key, char *passphrase) * where the sequence-number increases from zero. As many of these * hashes are used as necessary. * - * NOTE! It is important that all _public_ data can be verified - * with reference to the _private_ data. There exist attacks based - * on modifying the public key but leaving the private section - * intact. - * - * With RSA, this is easy: verify that n = p*q, and also verify - * that e*d == 1 modulo (p-1)(q-1). With DSA, we need to store - * extra data in the private section other than just x, namely a - * hash of p||q||g. (It's then easy to verify that y is equal to - * g^x mod p.) + * For backwards compatibility with snapshots between 0.51 and + * 0.52, we also support the older key file format, which begins + * with "PuTTY-User-Key-File-1" (version number differs). In this + * format the Private-MAC: field only covers the private-plaintext + * field and nothing else (and without the 4-byte string length on + * the front too). Moreover, for RSA keys the Private-MAC: field + * can be replaced with a Private-Hash: field which is a plain + * SHA-1 hash instead of an HMAC. This is not allowable in DSA + * keys. (Yes, the old format was a mess. Guess why it changed :-) */ static int read_header(FILE * fp, char *header) @@ -415,7 +488,7 @@ static char *read_body(FILE * fp) int c; size = 128; - text = smalloc(size); + text = snewn(size, char); len = 0; text[len] = '\0'; @@ -433,7 +506,7 @@ static char *read_body(FILE * fp) } if (len + 1 > size) { size += 128; - text = srealloc(text, size); + text = sresize(text, size, char); } text[len++] = c; text[len] = '\0'; @@ -488,7 +561,7 @@ int base64_decode_atom(char *atom, unsigned char *out) return len; } -static char *read_blob(FILE * fp, int nlines, int *bloblen) +static unsigned char *read_blob(FILE * fp, int nlines, int *bloblen) { unsigned char *blob; char *line; @@ -496,7 +569,7 @@ static char *read_blob(FILE * fp, int nlines, int *bloblen) int i, j, k; /* We expect at most 64 base64 characters, ie 48 real bytes, per line. */ - blob = smalloc(48 * nlines); + blob = snewn(48 * nlines, unsigned char); len = 0; for (i = 0; i < nlines; i++) { line = read_body(fp); @@ -532,30 +605,44 @@ struct ssh2_userkey ssh2_wrong_passphrase = { NULL, NULL, NULL }; -struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) +struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, + char *passphrase, const char **errorstr) { FILE *fp; - char header[40], *b, *comment, *mac; + char header[40], *b, *encryption, *comment, *mac; const struct ssh_signkey *alg; struct ssh2_userkey *ret; int cipher, cipherblk; unsigned char *public_blob, *private_blob; int public_blob_len, private_blob_len; - int i, is_mac; + int i, is_mac, old_fmt; int passlen = passphrase ? strlen(passphrase) : 0; + const char *error = NULL; ret = NULL; /* return NULL for most errors */ - comment = mac = NULL; + encryption = comment = mac = NULL; public_blob = private_blob = NULL; - fp = fopen(filename, "rb"); - if (!fp) + fp = f_open(*filename, "rb"); + if (!fp) { + error = "can't open file"; goto error; + } /* Read the first header line which contains the key type. */ - if (!read_header(fp, header) - || 0 != strcmp(header, "PuTTY-User-Key-File-1")) + if (!read_header(fp, header)) goto error; + if (0 == strcmp(header, "PuTTY-User-Key-File-2")) { + old_fmt = 0; + } else if (0 == strcmp(header, "PuTTY-User-Key-File-1")) { + /* this is an old key file; warn and then continue */ + old_keyfile_warning(); + old_fmt = 1; + } else { + error = "not a PuTTY SSH-2 private key"; + goto error; + } + error = "file format error"; if ((b = read_body(fp)) == NULL) goto error; /* Select key algorithm structure. */ @@ -572,19 +659,18 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) /* Read the Encryption header line. */ if (!read_header(fp, header) || 0 != strcmp(header, "Encryption")) goto error; - if ((b = read_body(fp)) == NULL) + if ((encryption = read_body(fp)) == NULL) goto error; - if (!strcmp(b, "aes256-cbc")) { + if (!strcmp(encryption, "aes256-cbc")) { cipher = 1; cipherblk = 16; - } else if (!strcmp(b, "none")) { + } else if (!strcmp(encryption, "none")) { cipher = 0; cipherblk = 1; } else { - sfree(b); + sfree(encryption); goto error; } - sfree(b); /* Read the Comment header line. */ if (!read_header(fp, header) || 0 != strcmp(header, "Comment")) @@ -619,7 +705,8 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) if ((mac = read_body(fp)) == NULL) goto error; is_mac = 1; - } else if (0 == strcmp(header, "Private-Hash")) { + } else if (0 == strcmp(header, "Private-Hash") && + alg == &ssh_rsa && old_fmt) { if ((mac = read_body(fp)) == NULL) goto error; is_mac = 0; @@ -653,40 +740,78 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) } /* - * Verify the private hash. + * Verify the MAC. */ { char realmac[41]; unsigned char binary[20]; + unsigned char *macdata; + int maclen; + int free_macdata; + + if (old_fmt) { + /* MAC (or hash) only covers the private blob. */ + macdata = private_blob; + maclen = private_blob_len; + free_macdata = 0; + } else { + unsigned char *p; + int namelen = strlen(alg->name); + int enclen = strlen(encryption); + int commlen = strlen(comment); + maclen = (4 + namelen + + 4 + enclen + + 4 + commlen + + 4 + public_blob_len + + 4 + private_blob_len); + macdata = snewn(maclen, unsigned char); + p = macdata; +#define DO_STR(s,len) PUT_32BIT(p,(len));memcpy(p+4,(s),(len));p+=4+(len) + DO_STR(alg->name, namelen); + DO_STR(encryption, enclen); + DO_STR(comment, commlen); + DO_STR(public_blob, public_blob_len); + DO_STR(private_blob, private_blob_len); + + free_macdata = 1; + } if (is_mac) { SHA_State s; unsigned char mackey[20]; char header[] = "putty-private-key-file-mac-key"; - if (!passphrase) /* can't have MAC in unencrypted key */ - goto error; - SHA_Init(&s); SHA_Bytes(&s, header, sizeof(header)-1); - SHA_Bytes(&s, passphrase, passlen); + if (cipher && passphrase) + SHA_Bytes(&s, passphrase, passlen); SHA_Final(&s, mackey); - hmac_sha1_simple(mackey, 20, private_blob, private_blob_len, - binary); + hmac_sha1_simple(mackey, 20, macdata, maclen, binary); memset(mackey, 0, sizeof(mackey)); memset(&s, 0, sizeof(s)); } else { - SHA_Simple(private_blob, private_blob_len, binary); + SHA_Simple(macdata, maclen, binary); } + + if (free_macdata) { + memset(macdata, 0, maclen); + sfree(macdata); + } + for (i = 0; i < 20; i++) sprintf(realmac + 2 * i, "%02x", binary[i]); if (strcmp(mac, realmac)) { /* An incorrect MAC is an unconditional Error if the key is * unencrypted. Otherwise, it means Wrong Passphrase. */ - ret = cipher ? SSH2_WRONG_PASSPHRASE : NULL; + if (cipher) { + ret = SSH2_WRONG_PASSPHRASE; + } else { + error = "MAC failed"; + ret = NULL; + } goto error; } } @@ -695,7 +820,7 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) /* * Create and return the key. */ - ret = smalloc(sizeof(struct ssh2_userkey)); + ret = snew(struct ssh2_userkey); ret->alg = alg; ret->comment = comment; ret->data = alg->createkey(public_blob, public_blob_len, @@ -704,9 +829,14 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) sfree(ret->comment); sfree(ret); ret = NULL; + error = "createkey failed"; + goto error; } sfree(public_blob); sfree(private_blob); + sfree(encryption); + if (errorstr) + *errorstr = NULL; return ret; /* @@ -717,17 +847,21 @@ struct ssh2_userkey *ssh2_load_userkey(char *filename, char *passphrase) fclose(fp); if (comment) sfree(comment); + if (encryption) + sfree(encryption); if (mac) sfree(mac); if (public_blob) sfree(public_blob); if (private_blob) sfree(private_blob); + if (errorstr) + *errorstr = error; return ret; } -char *ssh2_userkey_loadpub(char *filename, char **algorithm, - int *pub_blob_len) +char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, + int *pub_blob_len, const char **errorstr) { FILE *fp; char header[40], *b; @@ -735,17 +869,24 @@ char *ssh2_userkey_loadpub(char *filename, char **algorithm, unsigned char *public_blob; int public_blob_len; int i; + const char *error = NULL; public_blob = NULL; - fp = fopen(filename, "rb"); - if (!fp) + fp = f_open(*filename, "rb"); + if (!fp) { + error = "can't open file"; goto error; + } /* Read the first header line which contains the key type. */ if (!read_header(fp, header) - || 0 != strcmp(header, "PuTTY-User-Key-File-1")) + || (0 != strcmp(header, "PuTTY-User-Key-File-2") && + 0 != strcmp(header, "PuTTY-User-Key-File-1"))) { + error = "not a PuTTY SSH-2 private key"; goto error; + } + error = "file format error"; if ((b = read_body(fp)) == NULL) goto error; /* Select key algorithm structure. Currently only ssh-rsa. */ @@ -784,9 +925,11 @@ char *ssh2_userkey_loadpub(char *filename, char **algorithm, goto error; fclose(fp); - *pub_blob_len = public_blob_len; - *algorithm = alg->name; - return public_blob; + if (pub_blob_len) + *pub_blob_len = public_blob_len; + if (algorithm) + *algorithm = alg->name; + return (char *)public_blob; /* * Error processing. @@ -796,10 +939,12 @@ char *ssh2_userkey_loadpub(char *filename, char **algorithm, fclose(fp); if (public_blob) sfree(public_blob); + if (errorstr) + *errorstr = error; return NULL; } -int ssh2_userkey_encrypted(char *filename, char **commentptr) +int ssh2_userkey_encrypted(const Filename *filename, char **commentptr) { FILE *fp; char header[40], *b, *comment; @@ -808,11 +953,12 @@ int ssh2_userkey_encrypted(char *filename, char **commentptr) if (commentptr) *commentptr = NULL; - fp = fopen(filename, "rb"); + fp = f_open(*filename, "rb"); if (!fp) return 0; if (!read_header(fp, header) - || 0 != strcmp(header, "PuTTY-User-Key-File-1")) { + || (0 != strcmp(header, "PuTTY-User-Key-File-2") && + 0 != strcmp(header, "PuTTY-User-Key-File-1"))) { fclose(fp); return 0; } @@ -861,52 +1007,30 @@ int base64_lines(int datalen) return (datalen + 47) / 48; } -void base64_encode_atom(unsigned char *data, int n, char *out) -{ - static const char base64_chars[] = - "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; - - unsigned word; - - word = data[0] << 16; - if (n > 1) - word |= data[1] << 8; - if (n > 2) - word |= data[2]; - out[0] = base64_chars[(word >> 18) & 0x3F]; - out[1] = base64_chars[(word >> 12) & 0x3F]; - if (n > 1) - out[2] = base64_chars[(word >> 6) & 0x3F]; - else - out[2] = '='; - if (n > 2) - out[3] = base64_chars[word & 0x3F]; - else - out[3] = '='; -} - -void base64_encode(FILE * fp, unsigned char *data, int datalen) +void base64_encode(FILE * fp, unsigned char *data, int datalen, int cpl) { int linelen = 0; char out[4]; - int n; + int n, i; while (datalen > 0) { - if (linelen >= 64) { - linelen = 0; - fputc('\n', fp); - } n = (datalen < 3 ? datalen : 3); base64_encode_atom(data, n, out); data += n; datalen -= n; - fwrite(out, 1, 4, fp); - linelen += 4; + for (i = 0; i < 4; i++) { + if (linelen >= cpl) { + linelen = 0; + fputc('\n', fp); + } + fputc(out[i], fp); + linelen++; + } } fputc('\n', fp); } -int ssh2_save_userkey(char *filename, struct ssh2_userkey *key, +int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, char *passphrase) { FILE *fp; @@ -914,7 +1038,7 @@ int ssh2_save_userkey(char *filename, struct ssh2_userkey *key, int pub_blob_len, priv_blob_len, priv_encrypted_len; int passlen; int cipherblk; - int i, is_mac; + int i; char *cipherstr; unsigned char priv_mac[20]; @@ -941,7 +1065,7 @@ int ssh2_save_userkey(char *filename, struct ssh2_userkey *key, } priv_encrypted_len = priv_blob_len + cipherblk - 1; priv_encrypted_len -= priv_encrypted_len % cipherblk; - priv_blob_encrypted = smalloc(priv_encrypted_len); + priv_blob_encrypted = snewn(priv_encrypted_len, unsigned char); memset(priv_blob_encrypted, 0, priv_encrypted_len); memcpy(priv_blob_encrypted, priv_blob, priv_blob_len); /* Create padding based on the SHA hash of the unpadded blob. This prevents @@ -951,33 +1075,46 @@ int ssh2_save_userkey(char *filename, struct ssh2_userkey *key, memcpy(priv_blob_encrypted + priv_blob_len, priv_mac, priv_encrypted_len - priv_blob_len); - /* Now create the private MAC. */ - if (passphrase) { + /* Now create the MAC. */ + { + unsigned char *macdata; + int maclen; + unsigned char *p; + int namelen = strlen(key->alg->name); + int enclen = strlen(cipherstr); + int commlen = strlen(key->comment); SHA_State s; unsigned char mackey[20]; char header[] = "putty-private-key-file-mac-key"; - passlen = strlen(passphrase); + maclen = (4 + namelen + + 4 + enclen + + 4 + commlen + + 4 + pub_blob_len + + 4 + priv_encrypted_len); + macdata = snewn(maclen, unsigned char); + p = macdata; +#define DO_STR(s,len) PUT_32BIT(p,(len));memcpy(p+4,(s),(len));p+=4+(len) + DO_STR(key->alg->name, namelen); + DO_STR(cipherstr, enclen); + DO_STR(key->comment, commlen); + DO_STR(pub_blob, pub_blob_len); + DO_STR(priv_blob_encrypted, priv_encrypted_len); SHA_Init(&s); SHA_Bytes(&s, header, sizeof(header)-1); - SHA_Bytes(&s, passphrase, passlen); + if (passphrase) + SHA_Bytes(&s, passphrase, strlen(passphrase)); SHA_Final(&s, mackey); - - hmac_sha1_simple(mackey, 20, - priv_blob_encrypted, priv_encrypted_len, - priv_mac); - is_mac = 1; - + hmac_sha1_simple(mackey, 20, macdata, maclen, priv_mac); + memset(macdata, 0, maclen); + sfree(macdata); memset(mackey, 0, sizeof(mackey)); memset(&s, 0, sizeof(s)); - } else { - SHA_Simple(priv_blob_encrypted, priv_encrypted_len, priv_mac); - is_mac = 0; } if (passphrase) { - char key[40]; + unsigned char key[40]; SHA_State s; passlen = strlen(passphrase); @@ -997,44 +1134,75 @@ int ssh2_save_userkey(char *filename, struct ssh2_userkey *key, memset(&s, 0, sizeof(s)); } - fp = fopen(filename, "w"); + fp = f_open(*filename, "w"); if (!fp) return 0; - fprintf(fp, "PuTTY-User-Key-File-1: %s\n", key->alg->name); + fprintf(fp, "PuTTY-User-Key-File-2: %s\n", key->alg->name); fprintf(fp, "Encryption: %s\n", cipherstr); fprintf(fp, "Comment: %s\n", key->comment); fprintf(fp, "Public-Lines: %d\n", base64_lines(pub_blob_len)); - base64_encode(fp, pub_blob, pub_blob_len); + base64_encode(fp, pub_blob, pub_blob_len, 64); fprintf(fp, "Private-Lines: %d\n", base64_lines(priv_encrypted_len)); - base64_encode(fp, priv_blob_encrypted, priv_encrypted_len); - if (is_mac) - fprintf(fp, "Private-MAC: "); - else - fprintf(fp, "Private-Hash: "); + base64_encode(fp, priv_blob_encrypted, priv_encrypted_len, 64); + fprintf(fp, "Private-MAC: "); for (i = 0; i < 20; i++) fprintf(fp, "%02x", priv_mac[i]); fprintf(fp, "\n"); fclose(fp); + + sfree(pub_blob); + memset(priv_blob, 0, priv_blob_len); + sfree(priv_blob); + sfree(priv_blob_encrypted); return 1; } /* ---------------------------------------------------------------------- - * A function to determine which version of SSH to try on a private - * key file. Returns 0 on failure, 1 or 2 on success. + * A function to determine the type of a private key file. Returns + * 0 on failure, 1 or 2 on success. */ -int keyfile_version(char *filename) +int key_type(const Filename *filename) { FILE *fp; + char buf[32]; + const char putty2_sig[] = "PuTTY-User-Key-File-"; + const char sshcom_sig[] = "---- BEGIN SSH2 ENCRYPTED PRIVAT"; + const char openssh_sig[] = "-----BEGIN "; int i; - fp = fopen(filename, "r"); + fp = f_open(*filename, "r"); if (!fp) - return 0; - i = fgetc(fp); + return SSH_KEYTYPE_UNOPENABLE; + i = fread(buf, 1, sizeof(buf), fp); fclose(fp); - if (i == 'S') - return 1; /* "SSH PRIVATE KEY FORMAT" etc */ - if (i == 'P') /* "PuTTY-User-Key-File" etc */ - return 2; - return 0; /* unrecognised or EOF */ + if (i < 0) + return SSH_KEYTYPE_UNOPENABLE; + if (i < 32) + return SSH_KEYTYPE_UNKNOWN; + if (!memcmp(buf, rsa_signature, sizeof(rsa_signature)-1)) + return SSH_KEYTYPE_SSH1; + if (!memcmp(buf, putty2_sig, sizeof(putty2_sig)-1)) + return SSH_KEYTYPE_SSH2; + if (!memcmp(buf, openssh_sig, sizeof(openssh_sig)-1)) + return SSH_KEYTYPE_OPENSSH; + if (!memcmp(buf, sshcom_sig, sizeof(sshcom_sig)-1)) + return SSH_KEYTYPE_SSHCOM; + return SSH_KEYTYPE_UNKNOWN; /* unrecognised or EOF */ +} + +/* + * Convert the type word to a string, for `wrong type' error + * messages. + */ +char *key_type_to_str(int type) +{ + switch (type) { + case SSH_KEYTYPE_UNOPENABLE: return "unable to open file"; break; + case SSH_KEYTYPE_UNKNOWN: return "not a private key"; break; + case SSH_KEYTYPE_SSH1: return "SSH1 private key"; break; + case SSH_KEYTYPE_SSH2: return "PuTTY SSH2 private key"; break; + case SSH_KEYTYPE_OPENSSH: return "OpenSSH SSH2 private key"; break; + case SSH_KEYTYPE_SSHCOM: return "ssh.com SSH2 private key"; break; + default: return "INTERNAL ERROR"; break; + } }