X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/51e9d3c00a3471f284e89ec1f59f38ca25f10c5f..HEAD:/sshpubk.c diff --git a/sshpubk.c b/sshpubk.c index 2d5ff1d7..ac9e0fa7 100644 --- a/sshpubk.c +++ b/sshpubk.c @@ -67,19 +67,15 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only, i += 4; /* Now the serious stuff. An ordinary SSH-1 public key. */ - i += makekey(buf + i, len, key, NULL, 1); - if (i < 0) + j = makekey(buf + i, len, key, NULL, 1); + if (j < 0) goto end; /* overran */ - - if (pub_only) { - ret = 1; - goto end; - } + i += j; /* Next, the comment field. */ - j = GET_32BIT(buf + i); + j = toint(GET_32BIT(buf + i)); i += 4; - if (len - i < j) + if (j < 0 || len - i < j) goto end; comment = snewn(j + 1, char); if (comment) { @@ -88,9 +84,17 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only, } i += j; if (commentptr) - *commentptr = comment; + *commentptr = dupstr(comment); if (key) key->comment = comment; + else + sfree(comment); + + if (pub_only) { + ret = 1; + goto end; + } + if (!key) { ret = ciphertype != 0; *error = NULL; @@ -105,7 +109,7 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only, 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 */ + smemclr(keybuf, sizeof(keybuf)); /* burn the evidence */ } /* @@ -147,7 +151,7 @@ static int loadrsakey_main(FILE * fp, struct RSAKey *key, int pub_only, ret = 1; end: - memset(buf, 0, sizeof(buf)); /* burn the evidence */ + smemclr(buf, sizeof(buf)); /* burn the evidence */ return ret; } @@ -159,7 +163,7 @@ int loadrsakey(const Filename *filename, struct RSAKey *key, char *passphrase, int ret = 0; const char *error = NULL; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) { error = "can't open file"; goto end; @@ -200,7 +204,7 @@ int rsakey_encrypted(const Filename *filename, char **comment) FILE *fp; char buf[64]; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) return 0; /* doesn't even exist */ @@ -225,7 +229,7 @@ int rsakey_encrypted(const Filename *filename, char **comment) * exponent, modulus). */ int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen, - const char **errorstr) + char **commentptr, const char **errorstr) { FILE *fp; char buf[64]; @@ -238,7 +242,7 @@ int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen, *bloblen = 0; ret = 0; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) { error = "can't open file"; goto end; @@ -250,12 +254,12 @@ int rsakey_pubblob(const Filename *filename, void **blob, int *bloblen, */ if (fgets(buf, sizeof(buf), fp) && !strcmp(buf, rsa_signature)) { memset(&key, 0, sizeof(key)); - if (loadrsakey_main(fp, &key, TRUE, NULL, NULL, &error)) { + if (loadrsakey_main(fp, &key, TRUE, commentptr, NULL, &error)) { *blob = rsa_public_blob(&key, bloblen); freersakey(&key); ret = 1; - fp = NULL; } + fp = NULL; /* loadrsakey_main unconditionally closes fp */ } else { error = "not an SSH-1 RSA file"; } @@ -355,13 +359,13 @@ int saversakey(const Filename *filename, struct RSAKey *key, char *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 */ + smemclr(keybuf, sizeof(keybuf)); /* burn the evidence */ } /* * Done. Write the result to the file. */ - fp = f_open(*filename, "wb"); + fp = f_open(filename, "wb", TRUE); if (fp) { int ret = (fwrite(buf, 1, p - buf, fp) == (size_t) (p - buf)); if (fclose(fp)) @@ -459,7 +463,7 @@ static int read_header(FILE * fp, char *header) int len = 39; int c; - while (len > 0) { + while (1) { c = fgetc(fp); if (c == '\n' || c == '\r' || c == EOF) return 0; /* failure */ @@ -492,16 +496,14 @@ static char *read_body(FILE * fp) while (1) { c = fgetc(fp); - if (c == '\r' || c == '\n') { - c = fgetc(fp); - if (c != '\r' && c != '\n' && c != EOF) - ungetc(c, fp); + if (c == '\r' || c == '\n' || c == EOF) { + if (c != EOF) { + c = fgetc(fp); + if (c != '\r' && c != '\n') + ungetc(c, fp); + } return text; } - if (c == EOF) { - sfree(text); - return NULL; - } if (len + 1 >= size) { size += 128; text = sresize(text, size, char); @@ -631,7 +633,7 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, encryption = comment = mac = NULL; public_blob = private_blob = NULL; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) { error = "can't open file"; goto error; @@ -646,6 +648,11 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, /* this is an old key file; warn and then continue */ old_keyfile_warning(); old_fmt = 1; + } else if (0 == strncmp(header, "PuTTY-User-Key-File-", 20)) { + /* this is a key file FROM THE FUTURE; refuse it, but with a + * more specific error message than the generic one below */ + error = "PuTTY key format too new"; + goto error; } else { error = "not a PuTTY SSH-2 private key"; goto error; @@ -673,7 +680,6 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, cipher = 0; cipherblk = 1; } else { - sfree(encryption); goto error; } @@ -793,14 +799,14 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, hmac_sha1_simple(mackey, 20, macdata, maclen, binary); - memset(mackey, 0, sizeof(mackey)); - memset(&s, 0, sizeof(s)); + smemclr(mackey, sizeof(mackey)); + smemclr(&s, sizeof(s)); } else { SHA_Simple(macdata, maclen, binary); } if (free_macdata) { - memset(macdata, 0, maclen); + smemclr(macdata, maclen); sfree(macdata); } @@ -865,8 +871,9 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, return ret; } -char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, - int *pub_blob_len, const char **errorstr) +unsigned char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, + int *pub_blob_len, char **commentptr, + const char **errorstr) { FILE *fp; char header[40], *b; @@ -875,10 +882,11 @@ char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, int public_blob_len; int i; const char *error = NULL; + char *comment; public_blob = NULL; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) { error = "can't open file"; goto error; @@ -888,7 +896,10 @@ char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, if (!read_header(fp, header) || (0 != strcmp(header, "PuTTY-User-Key-File-2") && 0 != strcmp(header, "PuTTY-User-Key-File-1"))) { - error = "not a PuTTY SSH-2 private key"; + if (0 == strncmp(header, "PuTTY-User-Key-File-", 20)) + error = "PuTTY key format too new"; + else + error = "not a PuTTY SSH-2 private key"; goto error; } error = "file format error"; @@ -912,9 +923,13 @@ char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, /* Read the Comment header line. */ if (!read_header(fp, header) || 0 != strcmp(header, "Comment")) goto error; - if ((b = read_body(fp)) == NULL) + if ((comment = read_body(fp)) == NULL) goto error; - sfree(b); /* we don't care */ + + if (commentptr) + *commentptr = comment; + else + sfree(comment); /* Read the Public-Lines header line and the public blob. */ if (!read_header(fp, header) || 0 != strcmp(header, "Public-Lines")) @@ -931,7 +946,7 @@ char *ssh2_userkey_loadpub(const Filename *filename, char **algorithm, *pub_blob_len = public_blob_len; if (algorithm) *algorithm = alg->name; - return (char *)public_blob; + return public_blob; /* * Error processing. @@ -955,7 +970,7 @@ int ssh2_userkey_encrypted(const Filename *filename, char **commentptr) if (commentptr) *commentptr = NULL; - fp = f_open(*filename, "rb"); + fp = f_open(filename, "rb", FALSE); if (!fp) return 0; if (!read_header(fp, header) @@ -993,6 +1008,8 @@ int ssh2_userkey_encrypted(const Filename *filename, char **commentptr) if (commentptr) *commentptr = comment; + else + sfree(comment); fclose(fp); if (!strcmp(b, "aes256-cbc")) @@ -1109,10 +1126,10 @@ int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, SHA_Bytes(&s, passphrase, strlen(passphrase)); SHA_Final(&s, mackey); hmac_sha1_simple(mackey, 20, macdata, maclen, priv_mac); - memset(macdata, 0, maclen); + smemclr(macdata, maclen); sfree(macdata); - memset(mackey, 0, sizeof(mackey)); - memset(&s, 0, sizeof(s)); + smemclr(mackey, sizeof(mackey)); + smemclr(&s, sizeof(s)); } if (passphrase) { @@ -1132,11 +1149,11 @@ int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, aes256_encrypt_pubkey(key, priv_blob_encrypted, priv_encrypted_len); - memset(key, 0, sizeof(key)); - memset(&s, 0, sizeof(s)); + smemclr(key, sizeof(key)); + smemclr(&s, sizeof(s)); } - fp = f_open(*filename, "w"); + fp = f_open(filename, "w", TRUE); if (!fp) return 0; fprintf(fp, "PuTTY-User-Key-File-2: %s\n", key->alg->name); @@ -1153,7 +1170,7 @@ int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, fclose(fp); sfree(pub_blob); - memset(priv_blob, 0, priv_blob_len); + smemclr(priv_blob, priv_blob_len); sfree(priv_blob); sfree(priv_blob_encrypted); return 1; @@ -1172,7 +1189,7 @@ int key_type(const Filename *filename) const char openssh_sig[] = "-----BEGIN "; int i; - fp = f_open(*filename, "r"); + fp = f_open(filename, "r", FALSE); if (!fp) return SSH_KEYTYPE_UNOPENABLE; i = fread(buf, 1, sizeof(buf), fp);