| /* $OpenBSD: authfile.c,v 1.91 2011/05/23 07:24:57 djm Exp $ */ |
| /* |
| * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, 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. |
| */ |
| |
| #include "includes.h" |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <sys/param.h> |
| #include <sys/uio.h> |
| |
| #include <openssl/err.h> |
| #include <openssl/evp.h> |
| #include <openssl/pem.h> |
| |
| /* compatibility with old or broken OpenSSL versions */ |
| #include "openbsd-compat/openssl-compat.h" |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdarg.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include "xmalloc.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" |
| |
| #define MAX_KEY_FILE_SIZE (1024 * 1024) |
| |
| /* Version identification string for SSH v1 identity files. */ |
| static const char authfile_id_string[] = |
| "SSH PRIVATE KEY FILE FORMAT 1.1\n"; |
| |
| /* |
| * Serialises the authentication (private) key to a blob, encrypting it with |
| * passphrase. The identification of the blob (lowest 64 bits of n) will |
| * precede the key to provide identification of the key without needing a |
| * passphrase. |
| */ |
| static int |
| key_private_rsa1_to_blob(Key *key, Buffer *blob, const char *passphrase, |
| const char *comment) |
| { |
| Buffer buffer, encrypted; |
| u_char buf[100], *cp; |
| int 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); |
| |
| buffer_append(blob, buffer_ptr(&encrypted), buffer_len(&encrypted)); |
| buffer_free(&encrypted); |
| |
| return 1; |
| } |
| |
| /* convert SSH v2 key in OpenSSL PEM format */ |
| static int |
| key_private_pem_to_blob(Key *key, Buffer *blob, const char *_passphrase, |
| const char *comment) |
| { |
| int success = 0; |
| int blen, 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 |
| const u_char *bptr; |
| BIO *bio; |
| |
| if (len > 0 && len <= 4) { |
| error("passphrase too short: have %d bytes, need > 4", len); |
| return 0; |
| } |
| if ((bio = BIO_new(BIO_s_mem())) == NULL) { |
| error("%s: BIO_new failed", __func__); |
| return 0; |
| } |
| switch (key->type) { |
| case KEY_DSA: |
| success = PEM_write_bio_DSAPrivateKey(bio, key->dsa, |
| cipher, passphrase, len, NULL, NULL); |
| break; |
| #ifdef OPENSSL_HAS_ECC |
| case KEY_ECDSA: |
| success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa, |
| cipher, passphrase, len, NULL, NULL); |
| break; |
| #endif |
| case KEY_RSA: |
| success = PEM_write_bio_RSAPrivateKey(bio, key->rsa, |
| cipher, passphrase, len, NULL, NULL); |
| break; |
| } |
| if (success) { |
| if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) |
| success = 0; |
| else |
| buffer_append(blob, bptr, blen); |
| } |
| BIO_free(bio); |
| return success; |
| } |
| |
| /* Save a key blob to a file */ |
| static int |
| key_save_private_blob(Buffer *keybuf, const char *filename) |
| { |
| int fd; |
| |
| if ((fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600)) < 0) { |
| error("open %s failed: %s.", filename, strerror(errno)); |
| return 0; |
| } |
| if (atomicio(vwrite, fd, buffer_ptr(keybuf), |
| buffer_len(keybuf)) != buffer_len(keybuf)) { |
| error("write to key file %s failed: %s", filename, |
| strerror(errno)); |
| close(fd); |
| unlink(filename); |
| return 0; |
| } |
| close(fd); |
| return 1; |
| } |
| |
| /* Serialise "key" to buffer "blob" */ |
| static int |
| key_private_to_blob(Key *key, Buffer *blob, const char *passphrase, |
| const char *comment) |
| { |
| switch (key->type) { |
| case KEY_RSA1: |
| return key_private_rsa1_to_blob(key, blob, passphrase, comment); |
| case KEY_DSA: |
| case KEY_ECDSA: |
| case KEY_RSA: |
| return key_private_pem_to_blob(key, blob, passphrase, comment); |
| default: |
| error("%s: cannot save key type %d", __func__, key->type); |
| return 0; |
| } |
| } |
| |
| int |
| key_save_private(Key *key, const char *filename, const char *passphrase, |
| const char *comment) |
| { |
| Buffer keyblob; |
| int success = 0; |
| |
| buffer_init(&keyblob); |
| if (!key_private_to_blob(key, &keyblob, passphrase, comment)) |
| goto out; |
| if (!key_save_private_blob(&keyblob, filename)) |
| goto out; |
| success = 1; |
| out: |
| buffer_free(&keyblob); |
| return success; |
| } |
| |
| /* |
| * Parse the public, unencrypted portion of a RSA1 key. |
| */ |
| static Key * |
| key_parse_public_rsa1(Buffer *blob, char **commentp) |
| { |
| Key *pub; |
| |
| /* Check that it is at least big enough to contain the ID string. */ |
| if (buffer_len(blob) < sizeof(authfile_id_string)) { |
| debug3("Truncated RSA1 identifier"); |
| return NULL; |
| } |
| |
| /* |
| * Make sure it begins with the id string. Consume the id string |
| * from the buffer. |
| */ |
| if (memcmp(buffer_ptr(blob), authfile_id_string, |
| sizeof(authfile_id_string)) != 0) { |
| debug3("Incorrect RSA1 identifier"); |
| return NULL; |
| } |
| buffer_consume(blob, sizeof(authfile_id_string)); |
| |
| /* Skip cipher type and reserved data. */ |
| (void) buffer_get_char(blob); /* cipher type */ |
| (void) buffer_get_int(blob); /* reserved */ |
| |
| /* Read the public key from the buffer. */ |
| (void) buffer_get_int(blob); |
| pub = key_new(KEY_RSA1); |
| buffer_get_bignum(blob, pub->rsa->n); |
| buffer_get_bignum(blob, pub->rsa->e); |
| if (commentp) |
| *commentp = buffer_get_string(blob, NULL); |
| /* The encrypted private part is not parsed by this function. */ |
| buffer_clear(blob); |
| |
| return pub; |
| } |
| |
| /* Load a key from a fd into a buffer */ |
| int |
| key_load_file(int fd, const char *filename, Buffer *blob) |
| { |
| u_char buf[1024]; |
| size_t len; |
| struct stat st; |
| |
| if (fstat(fd, &st) < 0) { |
| error("%s: fstat of key file %.200s%sfailed: %.100s", __func__, |
| filename == NULL ? "" : filename, |
| filename == NULL ? "" : " ", |
| strerror(errno)); |
| return 0; |
| } |
| if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 && |
| st.st_size > MAX_KEY_FILE_SIZE) { |
| toobig: |
| error("%s: key file %.200s%stoo large", __func__, |
| filename == NULL ? "" : filename, |
| filename == NULL ? "" : " "); |
| return 0; |
| } |
| buffer_init(blob); |
| for (;;) { |
| if ((len = atomicio(read, fd, buf, sizeof(buf))) == 0) { |
| if (errno == EPIPE) |
| break; |
| debug("%s: read from key file %.200s%sfailed: %.100s", |
| __func__, filename == NULL ? "" : filename, |
| filename == NULL ? "" : " ", strerror(errno)); |
| buffer_clear(blob); |
| bzero(buf, sizeof(buf)); |
| return 0; |
| } |
| buffer_append(blob, buf, len); |
| if (buffer_len(blob) > MAX_KEY_FILE_SIZE) { |
| buffer_clear(blob); |
| bzero(buf, sizeof(buf)); |
| goto toobig; |
| } |
| } |
| bzero(buf, sizeof(buf)); |
| if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 && |
| st.st_size != buffer_len(blob)) { |
| debug("%s: key file %.200s%schanged size while reading", |
| __func__, filename == NULL ? "" : filename, |
| filename == NULL ? "" : " "); |
| buffer_clear(blob); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* |
| * 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. |
| */ |
| static Key * |
| key_load_public_rsa1(int fd, const char *filename, char **commentp) |
| { |
| Buffer buffer; |
| Key *pub; |
| |
| buffer_init(&buffer); |
| if (!key_load_file(fd, filename, &buffer)) { |
| buffer_free(&buffer); |
| return NULL; |
| } |
| |
| pub = key_parse_public_rsa1(&buffer, commentp); |
| if (pub == NULL) |
| debug3("Could not load \"%s\" as a RSA1 public key", filename); |
| buffer_free(&buffer); |
| return pub; |
| } |
| |
| /* 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; |
| } |
| |
| static Key * |
| key_parse_private_rsa1(Buffer *blob, const char *passphrase, char **commentp) |
| { |
| int check1, check2, cipher_type; |
| Buffer decrypted; |
| u_char *cp; |
| CipherContext ciphercontext; |
| Cipher *cipher; |
| Key *prv = NULL; |
| |
| /* Check that it is at least big enough to contain the ID string. */ |
| if (buffer_len(blob) < sizeof(authfile_id_string)) { |
| debug3("Truncated RSA1 identifier"); |
| return NULL; |
| } |
| |
| /* |
| * Make sure it begins with the id string. Consume the id string |
| * from the buffer. |
| */ |
| if (memcmp(buffer_ptr(blob), authfile_id_string, |
| sizeof(authfile_id_string)) != 0) { |
| debug3("Incorrect RSA1 identifier"); |
| return NULL; |
| } |
| buffer_consume(blob, sizeof(authfile_id_string)); |
| |
| /* Read cipher type. */ |
| cipher_type = buffer_get_char(blob); |
| (void) buffer_get_int(blob); /* Reserved data. */ |
| |
| /* Read the public key from the buffer. */ |
| (void) buffer_get_int(blob); |
| prv = key_new_private(KEY_RSA1); |
| |
| buffer_get_bignum(blob, prv->rsa->n); |
| buffer_get_bignum(blob, prv->rsa->e); |
| if (commentp) |
| *commentp = buffer_get_string(blob, NULL); |
| else |
| (void)buffer_get_string_ptr(blob, NULL); |
| |
| /* Check that it is a supported cipher. */ |
| cipher = cipher_by_number(cipher_type); |
| if (cipher == NULL) { |
| debug("Unsupported RSA1 cipher %d", cipher_type); |
| goto fail; |
| } |
| /* Initialize space for decrypted data. */ |
| buffer_init(&decrypted); |
| cp = buffer_append_space(&decrypted, buffer_len(blob)); |
| |
| /* 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(blob), buffer_len(blob)); |
| cipher_cleanup(&ciphercontext); |
| memset(&ciphercontext, 0, sizeof(ciphercontext)); |
| buffer_clear(blob); |
| |
| 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 RSA1 key"); |
| /* 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("%s: RSA_blinding_on failed", __func__); |
| goto fail; |
| } |
| return prv; |
| |
| fail: |
| if (commentp) |
| xfree(*commentp); |
| key_free(prv); |
| return NULL; |
| } |
| |
| static Key * |
| key_parse_private_pem(Buffer *blob, int type, const char *passphrase, |
| char **commentp) |
| { |
| EVP_PKEY *pk = NULL; |
| Key *prv = NULL; |
| char *name = "<no key>"; |
| BIO *bio; |
| |
| if ((bio = BIO_new_mem_buf(buffer_ptr(blob), |
| buffer_len(blob))) == NULL) { |
| error("%s: BIO_new_mem_buf failed", __func__); |
| return NULL; |
| } |
| |
| pk = PEM_read_bio_PrivateKey(bio, NULL, NULL, (char *)passphrase); |
| BIO_free(bio); |
| if (pk == NULL) { |
| debug("%s: PEM_read_PrivateKey failed", __func__); |
| (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("%s: RSA_blinding_on failed", __func__); |
| 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 |
| #ifdef OPENSSL_HAS_ECC |
| } else if (pk->type == EVP_PKEY_EC && |
| (type == KEY_UNSPEC||type==KEY_ECDSA)) { |
| prv = key_new(KEY_UNSPEC); |
| prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk); |
| prv->type = KEY_ECDSA; |
| if ((prv->ecdsa_nid = key_ecdsa_key_to_nid(prv->ecdsa)) == -1 || |
| key_curve_nid_to_name(prv->ecdsa_nid) == NULL || |
| key_ec_validate_public(EC_KEY_get0_group(prv->ecdsa), |
| EC_KEY_get0_public_key(prv->ecdsa)) != 0 || |
| key_ec_validate_private(prv->ecdsa) != 0) { |
| error("%s: bad ECDSA key", __func__); |
| key_free(prv); |
| prv = NULL; |
| } |
| name = "ecdsa w/o comment"; |
| #ifdef DEBUG_PK |
| if (prv != NULL && prv->ecdsa != NULL) |
| key_dump_ec_key(prv->ecdsa); |
| #endif |
| #endif /* OPENSSL_HAS_ECC */ |
| } else { |
| error("%s: PEM_read_PrivateKey: mismatch or " |
| "unknown EVP_PKEY save_type %d", __func__, pk->save_type); |
| } |
| 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) : "<unknown>"); |
| return prv; |
| } |
| |
| Key * |
| key_load_private_pem(int fd, int type, const char *passphrase, |
| char **commentp) |
| { |
| Buffer buffer; |
| Key *prv; |
| |
| buffer_init(&buffer); |
| if (!key_load_file(fd, NULL, &buffer)) { |
| buffer_free(&buffer); |
| return NULL; |
| } |
| prv = key_parse_private_pem(&buffer, type, passphrase, commentp); |
| buffer_free(&buffer); |
| 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 required that your private key files are NOT accessible by others."); |
| error("This private key will be ignored."); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static Key * |
| key_parse_private_type(Buffer *blob, int type, const char *passphrase, |
| char **commentp) |
| { |
| switch (type) { |
| case KEY_RSA1: |
| return key_parse_private_rsa1(blob, passphrase, commentp); |
| case KEY_DSA: |
| case KEY_ECDSA: |
| case KEY_RSA: |
| case KEY_UNSPEC: |
| return key_parse_private_pem(blob, type, passphrase, commentp); |
| default: |
| error("%s: cannot parse key type %d", __func__, type); |
| break; |
| } |
| return NULL; |
| } |
| |
| Key * |
| key_load_private_type(int type, const char *filename, const char *passphrase, |
| char **commentp, int *perm_ok) |
| { |
| int fd; |
| Key *ret; |
| Buffer buffer; |
| |
| 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; |
| |
| buffer_init(&buffer); |
| if (!key_load_file(fd, filename, &buffer)) { |
| buffer_free(&buffer); |
| close(fd); |
| return NULL; |
| } |
| close(fd); |
| ret = key_parse_private_type(&buffer, type, passphrase, commentp); |
| buffer_free(&buffer); |
| return ret; |
| } |
| |
| Key * |
| key_parse_private(Buffer *buffer, const char *filename, |
| const char *passphrase, char **commentp) |
| { |
| Key *pub, *prv; |
| Buffer pubcopy; |
| |
| buffer_init(&pubcopy); |
| buffer_append(&pubcopy, buffer_ptr(buffer), buffer_len(buffer)); |
| /* it's a SSH v1 key if the public key part is readable */ |
| pub = key_parse_public_rsa1(&pubcopy, commentp); |
| buffer_free(&pubcopy); |
| if (pub == NULL) { |
| prv = key_parse_private_type(buffer, KEY_UNSPEC, |
| passphrase, NULL); |
| /* use the filename as a comment for PEM */ |
| if (commentp && prv) |
| *commentp = xstrdup(filename); |
| } else { |
| key_free(pub); |
| /* key_parse_public_rsa1() has already loaded the comment */ |
| prv = key_parse_private_type(buffer, KEY_RSA1, passphrase, |
| NULL); |
| } |
| return prv; |
| } |
| |
| Key * |
| key_load_private(const char *filename, const char *passphrase, |
| char **commentp) |
| { |
| Key *prv; |
| Buffer buffer; |
| 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; |
| } |
| |
| buffer_init(&buffer); |
| if (!key_load_file(fd, filename, &buffer)) { |
| buffer_free(&buffer); |
| close(fd); |
| return NULL; |
| } |
| close(fd); |
| |
| prv = key_parse_private(&buffer, filename, passphrase, commentp); |
| buffer_free(&buffer); |
| 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; |
| } |
| /* Abort loading if this looks like a private key */ |
| if (strncmp(cp, "-----BEGIN", 10) == 0) |
| break; |
| /* Skip leading whitespace. */ |
| for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) |
| ; |
| if (*cp) { |
| if (key_read(k, &cp) == 1) { |
| cp[strcspn(cp, "\r\n")] = '\0'; |
| if (commentp) { |
| *commentp = xstrdup(*cp ? |
| cp : filename); |
| } |
| fclose(f); |
| return 1; |
| } |
| } |
| } |
| fclose(f); |
| } |
| return 0; |
| } |
| |
| /* 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; |
| } |
| |
| /* Load the certificate associated with the named private key */ |
| Key * |
| key_load_cert(const char *filename) |
| { |
| Key *pub; |
| char *file; |
| |
| pub = key_new(KEY_UNSPEC); |
| xasprintf(&file, "%s-cert.pub", filename); |
| if (key_try_load_public(pub, file, NULL) == 1) { |
| xfree(file); |
| return pub; |
| } |
| xfree(file); |
| key_free(pub); |
| return NULL; |
| } |
| |
| /* Load private key and certificate */ |
| Key * |
| key_load_private_cert(int type, const char *filename, const char *passphrase, |
| int *perm_ok) |
| { |
| Key *key, *pub; |
| |
| switch (type) { |
| case KEY_RSA: |
| case KEY_DSA: |
| case KEY_ECDSA: |
| break; |
| default: |
| error("%s: unsupported key type", __func__); |
| return NULL; |
| } |
| |
| if ((key = key_load_private_type(type, filename, |
| passphrase, NULL, perm_ok)) == NULL) |
| return NULL; |
| |
| if ((pub = key_load_cert(filename)) == NULL) { |
| key_free(key); |
| return NULL; |
| } |
| |
| /* Make sure the private key matches the certificate */ |
| if (key_equal_public(key, pub) == 0) { |
| error("%s: certificate does not match private key %s", |
| __func__, filename); |
| } else if (key_to_certified(key, key_cert_is_legacy(pub)) != 0) { |
| error("%s: key_to_certified failed", __func__); |
| } else { |
| key_cert_copy(pub, key); |
| key_free(pub); |
| return key; |
| } |
| |
| key_free(key); |
| key_free(pub); |
| return NULL; |
| } |
| |
| /* |
| * Returns 1 if the specified "key" is listed in the file "filename", |
| * 0 if the key is not listed or -1 on error. |
| * If strict_type is set then the key type must match exactly, |
| * otherwise a comparison that ignores certficiate data is performed. |
| */ |
| int |
| key_in_file(Key *key, const char *filename, int strict_type) |
| { |
| FILE *f; |
| char line[SSH_MAX_PUBKEY_BYTES]; |
| char *cp; |
| u_long linenum = 0; |
| int ret = 0; |
| Key *pub; |
| int (*key_compare)(const Key *, const Key *) = strict_type ? |
| key_equal : key_equal_public; |
| |
| if ((f = fopen(filename, "r")) == NULL) { |
| if (errno == ENOENT) { |
| debug("%s: keyfile \"%s\" missing", __func__, filename); |
| return 0; |
| } else { |
| error("%s: could not open keyfile \"%s\": %s", __func__, |
| filename, strerror(errno)); |
| return -1; |
| } |
| } |
| |
| while (read_keyfile_line(f, filename, line, sizeof(line), |
| &linenum) != -1) { |
| cp = line; |
| |
| /* Skip leading whitespace. */ |
| for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) |
| ; |
| |
| /* Skip comments and empty lines */ |
| switch (*cp) { |
| case '#': |
| case '\n': |
| case '\0': |
| continue; |
| } |
| |
| pub = key_new(KEY_UNSPEC); |
| if (key_read(pub, &cp) != 1) { |
| key_free(pub); |
| continue; |
| } |
| if (key_compare(key, pub)) { |
| ret = 1; |
| key_free(pub); |
| break; |
| } |
| key_free(pub); |
| } |
| fclose(f); |
| return ret; |
| } |
| |