X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/46ea69c5092639d17440f906f4f70f599e592ab9..a858eae93b4e020c5edabf092161ae9b791cef0d:/authfile.c diff --git a/authfile.c b/authfile.c index 1649b605..2c615709 100644 --- a/authfile.c +++ b/authfile.c @@ -1,356 +1,694 @@ +/* $OpenBSD: authfile.c,v 1.79 2010/01/12 00:16:47 dtucker Exp $ */ /* + * Author: Tatu Ylonen + * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland + * All rights reserved + * This file contains functions for reading and writing identity files, and + * for reading the passphrase from the user. + * + * As far as I am concerned, the code I have written for this software + * can be used freely for any purpose. Any derived versions of this + * software must be clearly marked as such, and if the derived work is + * incompatible with the protocol description in the RFC file, it must be + * called by a name other than "ssh" or "Secure Shell". + * + * + * Copyright (c) 2000 Markus Friedl. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ -authfile.c - -Author: Tatu Ylonen - -Copyright (c) 1995 Tatu Ylonen , Espoo, Finland - All rights reserved +#include "includes.h" -Created: Mon Mar 27 03:52:05 1995 ylo +#include +#include +#include +#include -This file contains functions for reading and writing identity files, and -for reading the passphrase from the user. +#include +#include +#include -*/ +/* compatibility with old or broken OpenSSL versions */ +#include "openbsd-compat/openssl-compat.h" -#include "includes.h" -RCSID("$Id$"); - -#ifdef HAVE_OPENSSL -#include -#endif -#ifdef HAVE_SSL -#include -#endif +#include +#include +#include +#include +#include +#include +#include #include "xmalloc.h" -#include "buffer.h" -#include "bufaux.h" #include "cipher.h" +#include "buffer.h" +#include "key.h" #include "ssh.h" +#include "log.h" +#include "authfile.h" +#include "rsa.h" +#include "misc.h" +#include "atomicio.h" + +/* Version identification string for SSH v1 identity files. */ +static const char authfile_id_string[] = + "SSH PRIVATE KEY FILE FORMAT 1.1\n"; + +/* + * Saves the authentication (private) key in a file, encrypting it with + * passphrase. The identification of the file (lowest 64 bits of n) will + * precede the key to provide identification of the key without needing a + * passphrase. + */ + +static int +key_save_private_rsa1(Key *key, const char *filename, const char *passphrase, + const char *comment) +{ + Buffer buffer, encrypted; + u_char buf[100], *cp; + int fd, i, cipher_num; + CipherContext ciphercontext; + Cipher *cipher; + u_int32_t rnd; + + /* + * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting + * to another cipher; otherwise use SSH_AUTHFILE_CIPHER. + */ + cipher_num = (strcmp(passphrase, "") == 0) ? + SSH_CIPHER_NONE : SSH_AUTHFILE_CIPHER; + if ((cipher = cipher_by_number(cipher_num)) == NULL) + fatal("save_private_key_rsa: bad cipher"); + + /* This buffer is used to built the secret part of the private key. */ + buffer_init(&buffer); + + /* Put checkbytes for checking passphrase validity. */ + rnd = arc4random(); + buf[0] = rnd & 0xff; + buf[1] = (rnd >> 8) & 0xff; + buf[2] = buf[0]; + buf[3] = buf[1]; + buffer_append(&buffer, buf, 4); + + /* + * Store the private key (n and e will not be stored because they + * will be stored in plain text, and storing them also in encrypted + * format would just give known plaintext). + */ + buffer_put_bignum(&buffer, key->rsa->d); + buffer_put_bignum(&buffer, key->rsa->iqmp); + buffer_put_bignum(&buffer, key->rsa->q); /* reverse from SSL p */ + buffer_put_bignum(&buffer, key->rsa->p); /* reverse from SSL q */ + + /* Pad the part to be encrypted until its size is a multiple of 8. */ + while (buffer_len(&buffer) % 8 != 0) + buffer_put_char(&buffer, 0); + + /* This buffer will be used to contain the data in the file. */ + buffer_init(&encrypted); + + /* First store keyfile id string. */ + for (i = 0; authfile_id_string[i]; i++) + buffer_put_char(&encrypted, authfile_id_string[i]); + buffer_put_char(&encrypted, 0); + + /* Store cipher type. */ + buffer_put_char(&encrypted, cipher_num); + buffer_put_int(&encrypted, 0); /* For future extension */ + + /* Store public key. This will be in plain text. */ + buffer_put_int(&encrypted, BN_num_bits(key->rsa->n)); + buffer_put_bignum(&encrypted, key->rsa->n); + buffer_put_bignum(&encrypted, key->rsa->e); + buffer_put_cstring(&encrypted, comment); + + /* Allocate space for the private part of the key in the buffer. */ + cp = buffer_append_space(&encrypted, buffer_len(&buffer)); + + cipher_set_key_string(&ciphercontext, cipher, passphrase, + CIPHER_ENCRYPT); + cipher_crypt(&ciphercontext, cp, + buffer_ptr(&buffer), buffer_len(&buffer)); + cipher_cleanup(&ciphercontext); + memset(&ciphercontext, 0, sizeof(ciphercontext)); + + /* Destroy temporary data. */ + memset(buf, 0, sizeof(buf)); + buffer_free(&buffer); -/* Version identification string for identity files. */ -#define AUTHFILE_ID_STRING "SSH PRIVATE KEY FILE FORMAT 1.1\n" + fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); + if (fd < 0) { + error("open %s failed: %s.", filename, strerror(errno)); + buffer_free(&encrypted); + return 0; + } + if (atomicio(vwrite, fd, buffer_ptr(&encrypted), + buffer_len(&encrypted)) != buffer_len(&encrypted)) { + error("write to key file %s failed: %s", filename, + strerror(errno)); + buffer_free(&encrypted); + close(fd); + unlink(filename); + return 0; + } + close(fd); + buffer_free(&encrypted); + return 1; +} -/* Saves the authentication (private) key in a file, encrypting it with - passphrase. The identification of the file (lowest 64 bits of n) - will precede the key to provide identification of the key without - needing a passphrase. */ +/* save SSH v2 key in OpenSSL PEM format */ +static int +key_save_private_pem(Key *key, const char *filename, const char *_passphrase, + const char *comment) +{ + FILE *fp; + int fd; + int success = 0; + int len = strlen(_passphrase); + u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL; +#if (OPENSSL_VERSION_NUMBER < 0x00907000L) + const EVP_CIPHER *cipher = (len > 0) ? EVP_des_ede3_cbc() : NULL; +#else + const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL; +#endif + + if (len > 0 && len <= 4) { + error("passphrase too short: have %d bytes, need > 4", len); + return 0; + } + fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600); + if (fd < 0) { + error("open %s failed: %s.", filename, strerror(errno)); + return 0; + } + fp = fdopen(fd, "w"); + if (fp == NULL) { + error("fdopen %s failed: %s.", filename, strerror(errno)); + close(fd); + return 0; + } + switch (key->type) { + case KEY_DSA: + success = PEM_write_DSAPrivateKey(fp, key->dsa, + cipher, passphrase, len, NULL, NULL); + break; + case KEY_RSA: + success = PEM_write_RSAPrivateKey(fp, key->rsa, + cipher, passphrase, len, NULL, NULL); + break; + } + fclose(fp); + return success; +} int -save_private_key(const char *filename, const char *passphrase, - RSA *key, const char *comment) +key_save_private(Key *key, const char *filename, const char *passphrase, + const char *comment) { - Buffer buffer, encrypted; - char buf[100], *cp; - int f, i; - CipherContext cipher; - int cipher_type; - u_int32_t rand; - - /* If the passphrase is empty, use SSH_CIPHER_NONE to ease converting to - another cipher; otherwise use SSH_AUTHFILE_CIPHER. */ - if (strcmp(passphrase, "") == 0) - cipher_type = SSH_CIPHER_NONE; - else - cipher_type = SSH_AUTHFILE_CIPHER; - - /* This buffer is used to built the secret part of the private key. */ - buffer_init(&buffer); - - /* Put checkbytes for checking passphrase validity. */ - rand = arc4random(); - buf[0] = rand & 0xff; - buf[1] = (rand >> 8) & 0xff; - buf[2] = buf[0]; - buf[3] = buf[1]; - buffer_append(&buffer, buf, 4); - - /* Store the private key (n and e will not be stored because they will - be stored in plain text, and storing them also in encrypted format - would just give known plaintext). */ - buffer_put_bignum(&buffer, key->d); - buffer_put_bignum(&buffer, key->iqmp); - buffer_put_bignum(&buffer, key->q); /* reverse from SSL p */ - buffer_put_bignum(&buffer, key->p); /* reverse from SSL q */ - - /* Pad the part to be encrypted until its size is a multiple of 8. */ - while (buffer_len(&buffer) % 8 != 0) - buffer_put_char(&buffer, 0); - - /* This buffer will be used to contain the data in the file. */ - buffer_init(&encrypted); - - /* First store keyfile id string. */ - cp = AUTHFILE_ID_STRING; - for (i = 0; cp[i]; i++) - buffer_put_char(&encrypted, cp[i]); - buffer_put_char(&encrypted, 0); - - /* Store cipher type. */ - buffer_put_char(&encrypted, cipher_type); - buffer_put_int(&encrypted, 0); /* For future extension */ - - /* Store public key. This will be in plain text. */ - buffer_put_int(&encrypted, BN_num_bits(key->n)); - buffer_put_bignum(&encrypted, key->n); - buffer_put_bignum(&encrypted, key->e); - buffer_put_string(&encrypted, comment, strlen(comment)); - - /* Allocate space for the private part of the key in the buffer. */ - buffer_append_space(&encrypted, &cp, buffer_len(&buffer)); - - cipher_set_key_string(&cipher, cipher_type, passphrase, 1); - cipher_encrypt(&cipher, (unsigned char *)cp, - (unsigned char *)buffer_ptr(&buffer), - buffer_len(&buffer)); - memset(&cipher, 0, sizeof(cipher)); - - /* Destroy temporary data. */ - memset(buf, 0, sizeof(buf)); - buffer_free(&buffer); - - /* Write to a file. */ - f = open(filename, O_WRONLY|O_CREAT|O_TRUNC, 0600); - if (f < 0) - return 0; - - if (write(f, buffer_ptr(&encrypted), buffer_len(&encrypted)) != - buffer_len(&encrypted)) - { - debug("Write to key file %.200s failed: %.100s", filename, - strerror(errno)); - buffer_free(&encrypted); - close(f); - remove(filename); - return 0; - } - close(f); - buffer_free(&encrypted); - return 1; + switch (key->type) { + case KEY_RSA1: + return key_save_private_rsa1(key, filename, passphrase, + comment); + case KEY_DSA: + case KEY_RSA: + return key_save_private_pem(key, filename, passphrase, + comment); + default: + break; + } + error("key_save_private: cannot save key type %d", key->type); + return 0; } -/* Loads the public part of the key file. Returns 0 if an error - was encountered (the file does not exist or is not readable), and - non-zero otherwise. */ +/* + * Loads the public part of the ssh v1 key file. Returns NULL if an error was + * encountered (the file does not exist or is not readable), and the key + * otherwise. + */ -int -load_public_key(const char *filename, RSA *pub, - char **comment_return) +static Key * +key_load_public_rsa1(int fd, const char *filename, char **commentp) { - int f, i; - off_t len; - Buffer buffer; - char *cp; - - /* Read data from the file into the buffer. */ - f = open(filename, O_RDONLY); - if (f < 0) - return 0; - - len = lseek(f, (off_t)0, SEEK_END); - lseek(f, (off_t)0, SEEK_SET); - - buffer_init(&buffer); - buffer_append_space(&buffer, &cp, len); - - if (read(f, cp, (size_t)len) != (size_t)len) - { - debug("Read from key file %.200s failed: %.100s", filename, - strerror(errno)); - buffer_free(&buffer); - close(f); - return 0; - } - close(f); - - /* Check that it is at least big enought to contain the ID string. */ - if (len < strlen(AUTHFILE_ID_STRING) + 1) - { - debug("Bad key file %.200s.", filename); - buffer_free(&buffer); - return 0; - } - - /* Make sure it begins with the id string. Consume the id string from - the buffer. */ - for (i = 0; i < (unsigned int)strlen(AUTHFILE_ID_STRING) + 1; i++) - if (buffer_get_char(&buffer) != (unsigned char)AUTHFILE_ID_STRING[i]) - { - debug("Bad key file %.200s.", filename); + Buffer buffer; + Key *pub; + struct stat st; + char *cp; + u_int i; + size_t len; + + if (fstat(fd, &st) < 0) { + error("fstat for key file %.200s failed: %.100s", + filename, strerror(errno)); + return NULL; + } + if (st.st_size > 1*1024*1024) { + error("key file %.200s too large", filename); + return NULL; + } + len = (size_t)st.st_size; /* truncated */ + + buffer_init(&buffer); + cp = buffer_append_space(&buffer, len); + + if (atomicio(read, fd, cp, len) != len) { + debug("Read from key file %.200s failed: %.100s", filename, + strerror(errno)); + buffer_free(&buffer); + return NULL; + } + + /* Check that it is at least big enough to contain the ID string. */ + if (len < sizeof(authfile_id_string)) { + debug3("Not a RSA1 key file %.200s.", filename); + buffer_free(&buffer); + return NULL; + } + /* + * Make sure it begins with the id string. Consume the id string + * from the buffer. + */ + for (i = 0; i < sizeof(authfile_id_string); i++) + if (buffer_get_char(&buffer) != authfile_id_string[i]) { + debug3("Not a RSA1 key file %.200s.", filename); + buffer_free(&buffer); + return NULL; + } + /* Skip cipher type and reserved data. */ + (void) buffer_get_char(&buffer); /* cipher type */ + (void) buffer_get_int(&buffer); /* reserved */ + + /* Read the public key from the buffer. */ + (void) buffer_get_int(&buffer); + pub = key_new(KEY_RSA1); + buffer_get_bignum(&buffer, pub->rsa->n); + buffer_get_bignum(&buffer, pub->rsa->e); + if (commentp) + *commentp = buffer_get_string(&buffer, NULL); + /* The encrypted private part is not parsed by this function. */ + buffer_free(&buffer); - return 0; - } - - /* Skip cipher type and reserved data. */ - (void)buffer_get_char(&buffer); /* cipher type */ - (void)buffer_get_int(&buffer); /* reserved */ - - /* Read the public key from the buffer. */ - buffer_get_int(&buffer); - pub->n = BN_new(); - buffer_get_bignum(&buffer, pub->n); - pub->e = BN_new(); - buffer_get_bignum(&buffer, pub->e); - if (comment_return) - *comment_return = buffer_get_string(&buffer, NULL); - /* The encrypted private part is not parsed by this function. */ - - buffer_free(&buffer); - - return 1; + return pub; } -/* Loads the private key from the file. Returns 0 if an error is encountered - (file does not exist or is not readable, or passphrase is bad). - This initializes the private key. */ +/* load public key from private-key file, works only for SSH v1 */ +Key * +key_load_public_type(int type, const char *filename, char **commentp) +{ + Key *pub; + int fd; + + if (type == KEY_RSA1) { + fd = open(filename, O_RDONLY); + if (fd < 0) + return NULL; + pub = key_load_public_rsa1(fd, filename, commentp); + close(fd); + return pub; + } + return NULL; +} -int -load_private_key(const char *filename, const char *passphrase, - RSA *prv, char **comment_return) +/* + * Loads the private key from the file. Returns 0 if an error is encountered + * (file does not exist or is not readable, or passphrase is bad). This + * initializes the private key. + * Assumes we are called under uid of the owner of the file. + */ + +static Key * +key_load_private_rsa1(int fd, const char *filename, const char *passphrase, + char **commentp) { - int f, i, check1, check2, cipher_type; - off_t len; - Buffer buffer, decrypted; - char *cp; - CipherContext cipher; - BN_CTX *ctx; - BIGNUM *aux; - struct stat st; - - /* Read the file into the buffer. */ - f = open(filename, O_RDONLY); - if (f < 0) - return 0; - - /* We assume we are called under uid of the owner of the file */ - if (fstat(f, &st) < 0 || - (st.st_uid != 0 && st.st_uid != getuid()) || - (st.st_mode & 077) != 0) { - error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); - error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @"); - error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); - error("Bad ownership or mode(0%3.3o) for '%s'.", - st.st_mode & 0777, filename); - error("It is recommended that your private key files are NOT accessible by others."); - return 0; - } - - len = lseek(f, (off_t)0, SEEK_END); - lseek(f, (off_t)0, SEEK_SET); - - buffer_init(&buffer); - buffer_append_space(&buffer, &cp, len); - - if (read(f, cp, (size_t)len) != (size_t)len) - { - debug("Read from key file %.200s failed: %.100s", filename, - strerror(errno)); - buffer_free(&buffer); - close(f); - return 0; - } - close(f); - - /* Check that it is at least big enought to contain the ID string. */ - if (len < strlen(AUTHFILE_ID_STRING) + 1) - { - debug("Bad key file %.200s.", filename); - buffer_free(&buffer); - return 0; - } - - /* Make sure it begins with the id string. Consume the id string from - the buffer. */ - for (i = 0; i < (unsigned int)strlen(AUTHFILE_ID_STRING) + 1; i++) - if (buffer_get_char(&buffer) != (unsigned char)AUTHFILE_ID_STRING[i]) - { - debug("Bad key file %.200s.", filename); + u_int i; + int check1, check2, cipher_type; + size_t len; + Buffer buffer, decrypted; + u_char *cp; + CipherContext ciphercontext; + Cipher *cipher; + Key *prv = NULL; + struct stat st; + + if (fstat(fd, &st) < 0) { + error("fstat for key file %.200s failed: %.100s", + filename, strerror(errno)); + close(fd); + return NULL; + } + if (st.st_size > 1*1024*1024) { + error("key file %.200s too large", filename); + close(fd); + return (NULL); + } + len = (size_t)st.st_size; /* truncated */ + + buffer_init(&buffer); + cp = buffer_append_space(&buffer, len); + + if (atomicio(read, fd, cp, len) != len) { + debug("Read from key file %.200s failed: %.100s", filename, + strerror(errno)); + buffer_free(&buffer); + close(fd); + return NULL; + } + + /* Check that it is at least big enough to contain the ID string. */ + if (len < sizeof(authfile_id_string)) { + debug3("Not a RSA1 key file %.200s.", filename); + buffer_free(&buffer); + close(fd); + return NULL; + } + /* + * Make sure it begins with the id string. Consume the id string + * from the buffer. + */ + for (i = 0; i < sizeof(authfile_id_string); i++) + if (buffer_get_char(&buffer) != authfile_id_string[i]) { + debug3("Not a RSA1 key file %.200s.", filename); + buffer_free(&buffer); + close(fd); + return NULL; + } + + /* Read cipher type. */ + cipher_type = buffer_get_char(&buffer); + (void) buffer_get_int(&buffer); /* Reserved data. */ + + /* Read the public key from the buffer. */ + (void) buffer_get_int(&buffer); + prv = key_new_private(KEY_RSA1); + + buffer_get_bignum(&buffer, prv->rsa->n); + buffer_get_bignum(&buffer, prv->rsa->e); + if (commentp) + *commentp = buffer_get_string(&buffer, NULL); + else + xfree(buffer_get_string(&buffer, NULL)); + + /* Check that it is a supported cipher. */ + cipher = cipher_by_number(cipher_type); + if (cipher == NULL) { + debug("Unsupported cipher %d used in key file %.200s.", + cipher_type, filename); + buffer_free(&buffer); + goto fail; + } + /* Initialize space for decrypted data. */ + buffer_init(&decrypted); + cp = buffer_append_space(&decrypted, buffer_len(&buffer)); + + /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */ + cipher_set_key_string(&ciphercontext, cipher, passphrase, + CIPHER_DECRYPT); + cipher_crypt(&ciphercontext, cp, + buffer_ptr(&buffer), buffer_len(&buffer)); + cipher_cleanup(&ciphercontext); + memset(&ciphercontext, 0, sizeof(ciphercontext)); buffer_free(&buffer); + + check1 = buffer_get_char(&decrypted); + check2 = buffer_get_char(&decrypted); + if (check1 != buffer_get_char(&decrypted) || + check2 != buffer_get_char(&decrypted)) { + if (strcmp(passphrase, "") != 0) + debug("Bad passphrase supplied for key file %.200s.", + filename); + /* Bad passphrase. */ + buffer_free(&decrypted); + goto fail; + } + /* Read the rest of the private key. */ + buffer_get_bignum(&decrypted, prv->rsa->d); + buffer_get_bignum(&decrypted, prv->rsa->iqmp); /* u */ + /* in SSL and SSH v1 p and q are exchanged */ + buffer_get_bignum(&decrypted, prv->rsa->q); /* p */ + buffer_get_bignum(&decrypted, prv->rsa->p); /* q */ + + /* calculate p-1 and q-1 */ + rsa_generate_additional_parameters(prv->rsa); + + buffer_free(&decrypted); + + /* enable blinding */ + if (RSA_blinding_on(prv->rsa, NULL) != 1) { + error("key_load_private_rsa1: RSA_blinding_on failed"); + goto fail; + } + close(fd); + return prv; + +fail: + if (commentp) + xfree(*commentp); + close(fd); + key_free(prv); + return NULL; +} + +Key * +key_load_private_pem(int fd, int type, const char *passphrase, + char **commentp) +{ + FILE *fp; + EVP_PKEY *pk = NULL; + Key *prv = NULL; + char *name = ""; + + fp = fdopen(fd, "r"); + if (fp == NULL) { + error("fdopen failed: %s", strerror(errno)); + close(fd); + return NULL; + } + pk = PEM_read_PrivateKey(fp, NULL, NULL, (char *)passphrase); + if (pk == NULL) { + debug("PEM_read_PrivateKey failed"); + (void)ERR_get_error(); + } else if (pk->type == EVP_PKEY_RSA && + (type == KEY_UNSPEC||type==KEY_RSA)) { + prv = key_new(KEY_UNSPEC); + prv->rsa = EVP_PKEY_get1_RSA(pk); + prv->type = KEY_RSA; + name = "rsa w/o comment"; +#ifdef DEBUG_PK + RSA_print_fp(stderr, prv->rsa, 8); +#endif + if (RSA_blinding_on(prv->rsa, NULL) != 1) { + error("key_load_private_pem: RSA_blinding_on failed"); + key_free(prv); + prv = NULL; + } + } else if (pk->type == EVP_PKEY_DSA && + (type == KEY_UNSPEC||type==KEY_DSA)) { + prv = key_new(KEY_UNSPEC); + prv->dsa = EVP_PKEY_get1_DSA(pk); + prv->type = KEY_DSA; + name = "dsa w/o comment"; +#ifdef DEBUG_PK + DSA_print_fp(stderr, prv->dsa, 8); +#endif + } else { + error("PEM_read_PrivateKey: mismatch or " + "unknown EVP_PKEY save_type %d", pk->save_type); + } + fclose(fp); + if (pk != NULL) + EVP_PKEY_free(pk); + if (prv != NULL && commentp) + *commentp = xstrdup(name); + debug("read PEM private key done: type %s", + prv ? key_type(prv) : ""); + return prv; +} + +int +key_perm_ok(int fd, const char *filename) +{ + struct stat st; + + if (fstat(fd, &st) < 0) + return 0; + /* + * if a key owned by the user is accessed, then we check the + * permissions of the file. if the key owned by a different user, + * then we don't care. + */ +#ifdef HAVE_CYGWIN + if (check_ntsec(filename)) +#endif + if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) { + error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); + error("@ WARNING: UNPROTECTED PRIVATE KEY FILE! @"); + error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); + error("Permissions 0%3.3o for '%s' are too open.", + (u_int)st.st_mode & 0777, filename); + error("It is recommended that your private key files are NOT accessible by others."); + error("This private key will be ignored."); + return 0; + } + return 1; +} + +Key * +key_load_private_type(int type, const char *filename, const char *passphrase, + char **commentp, int *perm_ok) +{ + int fd; + + fd = open(filename, O_RDONLY); + if (fd < 0) { + debug("could not open key file '%s': %s", filename, + strerror(errno)); + if (perm_ok != NULL) + *perm_ok = 0; + return NULL; + } + if (!key_perm_ok(fd, filename)) { + if (perm_ok != NULL) + *perm_ok = 0; + error("bad permissions: ignore key: %s", filename); + close(fd); + return NULL; + } + if (perm_ok != NULL) + *perm_ok = 1; + switch (type) { + case KEY_RSA1: + return key_load_private_rsa1(fd, filename, passphrase, + commentp); + /* closes fd */ + case KEY_DSA: + case KEY_RSA: + case KEY_UNSPEC: + return key_load_private_pem(fd, type, passphrase, commentp); + /* closes fd */ + default: + close(fd); + break; + } + return NULL; +} + +Key * +key_load_private(const char *filename, const char *passphrase, + char **commentp) +{ + Key *pub, *prv; + int fd; + + fd = open(filename, O_RDONLY); + if (fd < 0) { + debug("could not open key file '%s': %s", filename, + strerror(errno)); + return NULL; + } + if (!key_perm_ok(fd, filename)) { + error("bad permissions: ignore key: %s", filename); + close(fd); + return NULL; + } + pub = key_load_public_rsa1(fd, filename, commentp); + lseek(fd, (off_t) 0, SEEK_SET); /* rewind */ + if (pub == NULL) { + /* closes fd */ + prv = key_load_private_pem(fd, KEY_UNSPEC, passphrase, NULL); + /* use the filename as a comment for PEM */ + if (commentp && prv) + *commentp = xstrdup(filename); + } else { + /* it's a SSH v1 key if the public key part is readable */ + key_free(pub); + /* closes fd */ + prv = key_load_private_rsa1(fd, filename, passphrase, NULL); + } + return prv; +} + +static int +key_try_load_public(Key *k, const char *filename, char **commentp) +{ + FILE *f; + char line[SSH_MAX_PUBKEY_BYTES]; + char *cp; + u_long linenum = 0; + + f = fopen(filename, "r"); + if (f != NULL) { + while (read_keyfile_line(f, filename, line, sizeof(line), + &linenum) != -1) { + cp = line; + switch (*cp) { + case '#': + case '\n': + case '\0': + continue; + } + /* Skip leading whitespace. */ + for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) + ; + if (*cp) { + if (key_read(k, &cp) == 1) { + if (commentp) + *commentp=xstrdup(filename); + fclose(f); + return 1; + } + } + } + fclose(f); + } return 0; - } - - /* Read cipher type. */ - cipher_type = buffer_get_char(&buffer); - (void)buffer_get_int(&buffer); /* Reserved data. */ - - /* Read the public key from the buffer. */ - buffer_get_int(&buffer); - prv->n = BN_new(); - buffer_get_bignum(&buffer, prv->n); - prv->e = BN_new(); - buffer_get_bignum(&buffer, prv->e); - if (comment_return) - *comment_return = buffer_get_string(&buffer, NULL); - else - xfree(buffer_get_string(&buffer, NULL)); - - /* Check that it is a supported cipher. */ - if (((cipher_mask() | SSH_CIPHER_NONE | SSH_AUTHFILE_CIPHER) & - (1 << cipher_type)) == 0) - { - debug("Unsupported cipher %.100s used in key file %.200s.", - cipher_name(cipher_type), filename); - buffer_free(&buffer); - goto fail; - } - - /* Initialize space for decrypted data. */ - buffer_init(&decrypted); - buffer_append_space(&decrypted, &cp, buffer_len(&buffer)); - - /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */ - cipher_set_key_string(&cipher, cipher_type, passphrase, 0); - cipher_decrypt(&cipher, (unsigned char *)cp, - (unsigned char *)buffer_ptr(&buffer), - buffer_len(&buffer)); - - buffer_free(&buffer); - - check1 = buffer_get_char(&decrypted); - check2 = buffer_get_char(&decrypted); - if (check1 != buffer_get_char(&decrypted) || - check2 != buffer_get_char(&decrypted)) - { - if (strcmp(passphrase, "") != 0) - debug("Bad passphrase supplied for key file %.200s.", filename); - /* Bad passphrase. */ - buffer_free(&decrypted); - fail: - BN_clear_free(prv->n); - BN_clear_free(prv->e); - if (comment_return) - xfree(*comment_return); - return 0; - } - - /* Read the rest of the private key. */ - prv->d = BN_new(); - buffer_get_bignum(&decrypted, prv->d); - prv->iqmp = BN_new(); - buffer_get_bignum(&decrypted, prv->iqmp); /* u */ - /* in SSL and SSH p and q are exchanged */ - prv->q = BN_new(); - buffer_get_bignum(&decrypted, prv->q); /* p */ - prv->p = BN_new(); - buffer_get_bignum(&decrypted, prv->p); /* q */ - - ctx = BN_CTX_new(); - aux = BN_new(); - - BN_sub(aux, prv->q, BN_value_one()); - prv->dmq1 = BN_new(); - BN_mod(prv->dmq1, prv->d, aux, ctx); - - BN_sub(aux, prv->p, BN_value_one()); - prv->dmp1 = BN_new(); - BN_mod(prv->dmp1, prv->d, aux, ctx); - - BN_clear_free(aux); - BN_CTX_free(ctx); - - buffer_free(&decrypted); - - return 1; +} + +/* load public key from ssh v1 private or any pubkey file */ +Key * +key_load_public(const char *filename, char **commentp) +{ + Key *pub; + char file[MAXPATHLEN]; + + /* try rsa1 private key */ + pub = key_load_public_type(KEY_RSA1, filename, commentp); + if (pub != NULL) + return pub; + + /* try rsa1 public key */ + pub = key_new(KEY_RSA1); + if (key_try_load_public(pub, filename, commentp) == 1) + return pub; + key_free(pub); + + /* try ssh2 public key */ + pub = key_new(KEY_UNSPEC); + if (key_try_load_public(pub, filename, commentp) == 1) + return pub; + if ((strlcpy(file, filename, sizeof file) < sizeof(file)) && + (strlcat(file, ".pub", sizeof file) < sizeof(file)) && + (key_try_load_public(pub, file, commentp) == 1)) + return pub; + key_free(pub); + return NULL; }