/* $OpenBSD: authfile.c,v 1.94 2012/12/11 22:31:18 markus 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "cipher.h" #include "key.h" #include "ssh.h" #include "log.h" #include "authfile.h" #include "rsa.h" #include "misc.h" #include "atomicio.h" #include "sshbuf.h" #include "err.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 sshkey_private_rsa1_to_blob(struct sshkey *key, struct sshbuf *blob, const char *passphrase, const char *comment) { struct sshbuf *buffer = NULL, *encrypted = NULL; u_char buf[8]; int r, cipher_num; struct sshcipher_ctx ciphercontext; struct sshcipher *cipher; u_char *cp; /* * 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) return SSH_ERR_INTERNAL_ERROR; /* This buffer is used to build the secret part of the private key. */ if ((buffer = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; /* Put checkbytes for checking passphrase validity. */ if ((r = sshbuf_reserve(buffer, 4, &cp)) != 0) goto out; arc4random_buf(cp, 2); memcpy(cp + 2, cp, 2); /* * 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). * Note: q and p are stored in reverse order to SSL. */ if ((r = sshbuf_put_bignum1(buffer, key->rsa->d)) != 0 || (r = sshbuf_put_bignum1(buffer, key->rsa->iqmp)) != 0 || (r = sshbuf_put_bignum1(buffer, key->rsa->q)) != 0 || (r = sshbuf_put_bignum1(buffer, key->rsa->p)) != 0) goto out; /* Pad the part to be encrypted to a size that is a multiple of 8. */ bzero(buf, 8); if ((r = sshbuf_put(buffer, buf, 8 - (sshbuf_len(buffer) % 8))) != 0) goto out; /* This buffer will be used to contain the data in the file. */ if ((encrypted = sshbuf_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } /* First store keyfile id string. */ if ((r = sshbuf_put(encrypted, authfile_id_string, sizeof(authfile_id_string))) != 0) goto out; /* Store cipher type and "reserved" field. */ if ((r = sshbuf_put_u8(encrypted, cipher_num)) != 0 || (r = sshbuf_put_u32(encrypted, 0)) != 0) goto out; /* Store public key. This will be in plain text. */ if ((r = sshbuf_put_u32(encrypted, BN_num_bits(key->rsa->n))) != 0 || (r = sshbuf_put_bignum1(encrypted, key->rsa->n) != 0) || (r = sshbuf_put_bignum1(encrypted, key->rsa->e) != 0) || (r = sshbuf_put_cstring(encrypted, comment) != 0)) goto out; /* Allocate space for the private part of the key in the buffer. */ if ((r = sshbuf_reserve(encrypted, sshbuf_len(buffer), &cp)) != 0) goto out; if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase, CIPHER_ENCRYPT)) != 0) goto out; if ((r = cipher_crypt(&ciphercontext, cp, sshbuf_ptr(buffer), sshbuf_len(buffer), 0)) != 0) goto out; if ((r = cipher_cleanup(&ciphercontext)) != 0) goto out; r = sshbuf_putb(blob, encrypted); out: bzero(&ciphercontext, sizeof(ciphercontext)); bzero(buf, sizeof(buf)); if (buffer != NULL) sshbuf_free(buffer); if (encrypted != NULL) sshbuf_free(encrypted); return r; } /* convert SSH v2 key in OpenSSL PEM format */ static int sshkey_private_pem_to_blob(struct sshkey *key, struct sshbuf *blob, const char *_passphrase, const char *comment) { int success, r; int blen, len = strlen(_passphrase); u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL; const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL; const u_char *bptr; BIO *bio = NULL; if (len > 0 && len <= 4) return SSH_ERR_PASSPHRASE_TOO_SHORT; if ((bio = BIO_new(BIO_s_mem())) == NULL) return SSH_ERR_ALLOC_FAIL; switch (key->type) { case KEY_DSA: success = PEM_write_bio_DSAPrivateKey(bio, key->dsa, cipher, passphrase, len, NULL, NULL); break; case KEY_ECDSA: success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa, cipher, passphrase, len, NULL, NULL); break; case KEY_RSA: success = PEM_write_bio_RSAPrivateKey(bio, key->rsa, cipher, passphrase, len, NULL, NULL); break; default: success = 0; break; } if (success == 0) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) { r = SSH_ERR_INTERNAL_ERROR; goto out; } if ((r = sshbuf_put(blob, bptr, blen)) != 0) goto out; r = 0; out: BIO_free(bio); return r; } /* Save a key blob to a file */ static int sshkey_save_private_blob(struct sshbuf *keybuf, const char *filename) { int fd; if ((fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600)) < 0) return SSH_ERR_SYSTEM_ERROR; if (atomicio(vwrite, fd, (u_char *)sshbuf_ptr(keybuf), sshbuf_len(keybuf)) != sshbuf_len(keybuf)) { close(fd); unlink(filename); return SSH_ERR_SYSTEM_ERROR; } close(fd); return 0; } /* Serialise "key" to buffer "blob" */ static int sshkey_private_to_blob(struct sshkey *key, struct sshbuf *blob, const char *passphrase, const char *comment) { switch (key->type) { case KEY_RSA1: return sshkey_private_rsa1_to_blob(key, blob, passphrase, comment); case KEY_DSA: case KEY_ECDSA: case KEY_RSA: return sshkey_private_pem_to_blob(key, blob, passphrase, comment); default: return SSH_ERR_KEY_TYPE_UNKNOWN; } } int sshkey_save_private(struct sshkey *key, const char *filename, const char *passphrase, const char *comment) { struct sshbuf *keyblob = NULL; int r; if ((keyblob = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_private_to_blob(key, keyblob, passphrase, comment)) != 0) goto out; if ((r = sshkey_save_private_blob(keyblob, filename)) != 0) goto out; r = 0; out: sshbuf_free(keyblob); return r; } /* * Parse the public, unencrypted portion of a RSA1 key. */ int sshkey_parse_public_rsa1(struct sshbuf *blob, struct sshkey **keyp, char **commentp) { int r; struct sshkey *pub = NULL; struct sshbuf *copy = NULL; *keyp = NULL; if (commentp != NULL) *commentp = NULL; /* Check that it is at least big enough to contain the ID string. */ if (sshbuf_len(blob) < sizeof(authfile_id_string)) return SSH_ERR_INVALID_FORMAT; /* * Make sure it begins with the id string. Consume the id string * from the buffer. */ if (memcmp(sshbuf_ptr(blob), authfile_id_string, sizeof(authfile_id_string)) != 0) return SSH_ERR_INVALID_FORMAT; /* Make a working copy of the keyblob and skip past the magic */ if ((copy = sshbuf_fromb(blob)) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshbuf_consume(copy, sizeof(authfile_id_string))) != 0) goto out; /* Skip cipher type, reserved data and key bits. */ if ((r = sshbuf_get_u8(copy, NULL)) != 0 || /* cipher type */ (r = sshbuf_get_u32(copy, NULL)) != 0 || /* reserved */ (r = sshbuf_get_u32(copy, NULL)) != 0) /* key bits */ goto out; /* Read the public key from the buffer. */ if ((pub = sshkey_new(KEY_RSA1)) == NULL || (r = sshbuf_get_bignum1(copy, pub->rsa->n)) != 0 || (r = sshbuf_get_bignum1(copy, pub->rsa->e)) != 0) goto out; /* Finally, the comment */ if ((r = sshbuf_get_string(copy, (u_char**)commentp, NULL)) != 0) goto out; /* The encrypted private part is not parsed by this function. */ r = 0; *keyp = pub; pub = NULL; out: if (copy != NULL) sshbuf_free(copy); if (pub != NULL) sshkey_free(pub); return r; } /* Load a key from a fd into a buffer */ int sshkey_load_file(int fd, const char *filename, struct sshbuf *blob) { u_char buf[1024]; size_t len; struct stat st; int r; if (fstat(fd, &st) < 0) return SSH_ERR_SYSTEM_ERROR; if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 && st.st_size > MAX_KEY_FILE_SIZE) return SSH_ERR_INVALID_FORMAT; for (;;) { if ((len = atomicio(read, fd, buf, sizeof(buf))) == 0) { if (errno == EPIPE) break; r = SSH_ERR_SYSTEM_ERROR; goto out; } if ((r = sshbuf_put(blob, buf, len)) != 0) goto out; if (sshbuf_len(blob) > MAX_KEY_FILE_SIZE) { r = SSH_ERR_INVALID_FORMAT; goto out; } } if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 && st.st_size != (off_t)sshbuf_len(blob)) { r = SSH_ERR_FILE_CHANGED; goto out; } r = 0; out: bzero(buf, sizeof(buf)); if (r != 0) sshbuf_reset(blob); return r; } /* * 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 int sshkey_load_public_rsa1(int fd, const char *filename, struct sshkey **keyp, char **commentp) { struct sshbuf *buffer = NULL; int r; *keyp = NULL; if (commentp != NULL) *commentp = NULL; if ((buffer = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_load_file(fd, filename, buffer)) != 0) goto out; if ((r = sshkey_parse_public_rsa1(buffer, keyp, commentp)) != 0) goto out; r = 0; out: sshbuf_free(buffer); return r; } static int sshkey_parse_private_rsa1(struct sshbuf *blob, const char *passphrase, struct sshkey **keyp, char **commentp) { int r; u_int16_t check1, check2; u_int8_t cipher_type; struct sshbuf *decrypted = NULL, *copy = NULL; u_char *cp; char *comment = NULL; struct sshcipher_ctx ciphercontext; struct sshcipher *cipher; struct sshkey *prv = NULL; *keyp = NULL; if (commentp != NULL) *commentp = NULL; /* Check that it is at least big enough to contain the ID string. */ if (sshbuf_len(blob) < sizeof(authfile_id_string)) return SSH_ERR_INVALID_FORMAT; /* * Make sure it begins with the id string. Consume the id string * from the buffer. */ if (memcmp(sshbuf_ptr(blob), authfile_id_string, sizeof(authfile_id_string)) != 0) return SSH_ERR_INVALID_FORMAT; if ((prv = sshkey_new_private(KEY_RSA1)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((copy = sshbuf_fromb(blob)) == NULL || (decrypted = sshbuf_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshbuf_consume(copy, sizeof(authfile_id_string))) != 0) goto out; /* Read cipher type. */ if ((r = sshbuf_get_u8(copy, &cipher_type)) != 0 || (r = sshbuf_get_u32(copy, NULL)) != 0) /* reserved */ goto out; /* Read the public key and comment from the buffer. */ if ((r = sshbuf_get_u32(copy, NULL)) != 0 || /* key bits */ (r = sshbuf_get_bignum1(copy, prv->rsa->n)) != 0 || (r = sshbuf_get_bignum1(copy, prv->rsa->e)) != 0 || (r = sshbuf_get_cstring(copy, &comment, NULL)) != 0) goto out; /* Check that it is a supported cipher. */ cipher = cipher_by_number(cipher_type); if (cipher == NULL) { r = SSH_ERR_KEY_UNKNOWN_CIPHER; goto out; } /* Initialize space for decrypted data. */ if ((r = sshbuf_reserve(decrypted, sshbuf_len(copy), &cp)) != 0) goto out; /* Rest of the buffer is encrypted. Decrypt it using the passphrase. */ if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase, CIPHER_DECRYPT)) != 0) goto out; if ((r = cipher_crypt(&ciphercontext, cp, sshbuf_ptr(copy), sshbuf_len(copy), 0)) != 0) { cipher_cleanup(&ciphercontext); goto out; } if ((r = cipher_cleanup(&ciphercontext)) != 0) goto out; if ((r = sshbuf_get_u16(decrypted, &check1)) != 0 || (r = sshbuf_get_u16(decrypted, &check2)) != 0) goto out; if (check1 != check2) { r = SSH_ERR_KEY_WRONG_PASSPHRASE; goto out; } /* Read the rest of the private key. */ if ((r = sshbuf_get_bignum1(decrypted, prv->rsa->d)) != 0 || (r = sshbuf_get_bignum1(decrypted, prv->rsa->iqmp)) != 0 || (r = sshbuf_get_bignum1(decrypted, prv->rsa->q)) != 0 || (r = sshbuf_get_bignum1(decrypted, prv->rsa->p)) != 0) goto out; /* calculate p-1 and q-1 */ if ((r = rsa_generate_additional_parameters(prv->rsa)) != 0) goto out; /* enable blinding */ if (RSA_blinding_on(prv->rsa, NULL) != 1) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } r = 0; *keyp = prv; prv = NULL; if (commentp != NULL) { *commentp = comment; comment = NULL; } out: bzero(&ciphercontext, sizeof(ciphercontext)); if (comment != NULL) free(comment); if (prv != NULL) sshkey_free(prv); if (copy != NULL) sshbuf_free(copy); if (decrypted != NULL) sshbuf_free(decrypted); return r; } static int sshkey_parse_private_pem(struct sshbuf *blob, int type, const char *passphrase, struct sshkey **keyp, char **commentp) { EVP_PKEY *pk = NULL; struct sshkey *prv = NULL; char *name = ""; BIO *bio = NULL; int r; *keyp = NULL; if (commentp != NULL) *commentp = NULL; if ((bio = BIO_new_mem_buf((u_char *)sshbuf_ptr(blob), sshbuf_len(blob))) == NULL) return SSH_ERR_ALLOC_FAIL; if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL, (char *)passphrase)) == NULL) { r = SSH_ERR_KEY_WRONG_PASSPHRASE; goto out; } if (pk->type == EVP_PKEY_RSA && (type == KEY_UNSPEC || type == KEY_RSA)) { if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } 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) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } } else if (pk->type == EVP_PKEY_DSA && (type == KEY_UNSPEC || type == KEY_DSA)) { if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } 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 if (pk->type == EVP_PKEY_EC && (type == KEY_UNSPEC || type == KEY_ECDSA)) { if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk); prv->type = KEY_ECDSA; prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa); if (prv->ecdsa_nid == -1 || sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL || sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa), EC_KEY_get0_public_key(prv->ecdsa)) != 0 || sshkey_ec_validate_private(prv->ecdsa) != 0) { r = SSH_ERR_INVALID_FORMAT; goto out; } name = "ecdsa w/o comment"; #ifdef DEBUG_PK if (prv != NULL && prv->ecdsa != NULL) sshkey_dump_ec_key(prv->ecdsa); #endif } else { r = SSH_ERR_INVALID_FORMAT; goto out; } if (commentp != NULL && (*commentp = strdup(name)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } r = 0; *keyp = prv; prv = NULL; out: BIO_free(bio); if (pk != NULL) EVP_PKEY_free(pk); if (prv != NULL) sshkey_free(prv); return r; } int sshkey_load_private_pem(int fd, int type, const char *passphrase, struct sshkey **keyp, char **commentp) { struct sshbuf *buffer = NULL; int r; *keyp = NULL; if (commentp != NULL) *commentp = NULL; if ((buffer = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_load_file(fd, NULL, buffer)) != 0) goto out; if ((r = sshkey_parse_private_pem(buffer, type, passphrase, keyp, commentp)) != 0) goto out; r = 0; out: sshbuf_free(buffer); return r; } /* XXX remove error() calls from here? */ int sshkey_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. */ 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; } static int sshkey_parse_private_type(struct sshbuf *blob, int type, const char *passphrase, struct sshkey **keyp, char **commentp) { *keyp = NULL; if (commentp != NULL) *commentp = NULL; switch (type) { case KEY_RSA1: return sshkey_parse_private_rsa1(blob, passphrase, keyp, commentp); case KEY_DSA: case KEY_ECDSA: case KEY_RSA: case KEY_UNSPEC: return sshkey_parse_private_pem(blob, type, passphrase, keyp, commentp); default: return SSH_ERR_KEY_TYPE_UNKNOWN; } } /* XXX kill perm_ok now that we have SSH_ERR_KEY_BAD_PERMISSIONS? */ int sshkey_load_private_type(int type, const char *filename, const char *passphrase, struct sshkey **keyp, char **commentp, int *perm_ok) { int fd, r; struct sshbuf *buffer = NULL; *keyp = NULL; if (commentp != NULL) *commentp = NULL; if ((fd = open(filename, O_RDONLY)) < 0) { if (perm_ok != NULL) *perm_ok = 0; return SSH_ERR_SYSTEM_ERROR; } if (!sshkey_perm_ok(fd, filename)) { if (perm_ok != NULL) *perm_ok = 0; r = SSH_ERR_KEY_BAD_PERMISSIONS; goto out; } if (perm_ok != NULL) *perm_ok = 1; if ((buffer = sshbuf_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshkey_load_file(fd, filename, buffer)) != 0) goto out; if ((r = sshkey_parse_private_type(buffer, type, passphrase, keyp, commentp)) != 0) goto out; r = 0; out: close(fd); if (buffer != NULL) sshbuf_free(buffer); return r; } int sshkey_parse_private(struct sshbuf *buffer, const char *passphrase, const char *filename, struct sshkey **keyp, char **commentp) { struct sshkey *key; int r; *keyp = NULL; if (commentp != NULL) *commentp = NULL; /* it's a SSH v1 key if the public key part is readable */ if ((r = sshkey_parse_public_rsa1(buffer, &key, NULL)) == 0) { sshkey_free(key); return sshkey_parse_private_type(buffer, KEY_RSA1, passphrase, keyp, commentp); } if ((r = sshkey_parse_private_type(buffer, KEY_UNSPEC, passphrase, &key, NULL)) != 0) return r; if (commentp != NULL && (*commentp = strdup(filename)) == NULL) { sshkey_free(key); return SSH_ERR_ALLOC_FAIL; } *keyp = key; return 0; } /* XXX this is almost identical to sshkey_load_private_type() */ int sshkey_load_private(const char *filename, const char *passphrase, struct sshkey **keyp, char **commentp) { struct sshbuf *buffer = NULL; int r, fd; *keyp = NULL; if (commentp != NULL) *commentp = NULL; if ((fd = open(filename, O_RDONLY)) < 0) return SSH_ERR_SYSTEM_ERROR; if (!sshkey_perm_ok(fd, filename)) { r = SSH_ERR_KEY_BAD_PERMISSIONS; goto out; } if ((buffer = sshbuf_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshkey_load_file(fd, filename, buffer)) != 0 || (r = sshkey_parse_private(buffer, passphrase, filename, keyp, commentp)) != 0) goto out; r = 0; out: close(fd); if (buffer != NULL) sshbuf_free(buffer); return r; } static int sshkey_try_load_public(struct sshkey *k, const char *filename, char **commentp) { FILE *f; char line[SSH_MAX_PUBKEY_BYTES]; char *cp; u_long linenum = 0; int r; if (commentp != NULL) *commentp = NULL; if ((f = fopen(filename, "r")) == NULL) return SSH_ERR_SYSTEM_ERROR; 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 || strcmp(cp, authfile_id_string) == 0) break; /* Skip leading whitespace. */ for (; *cp && (*cp == ' ' || *cp == '\t'); cp++) ; if (*cp) { if ((r = sshkey_read(k, &cp)) == 0) { cp[strcspn(cp, "\r\n")] = '\0'; if (commentp) { *commentp = strdup(*cp ? cp : filename); if (*commentp == NULL) r = SSH_ERR_ALLOC_FAIL; } fclose(f); return r; } } } fclose(f); return SSH_ERR_INVALID_FORMAT; } /* load public key from ssh v1 private or any pubkey file */ int sshkey_load_public(const char *filename, struct sshkey **keyp, char **commentp) { struct sshkey *pub = NULL; char file[MAXPATHLEN]; int r, fd; *keyp = NULL; if (commentp != NULL) *commentp = NULL; /* try rsa1 private key */ if ((fd = open(filename, O_RDONLY)) < 0) goto skip; r = sshkey_load_public_rsa1(fd, filename, keyp, commentp); close(fd); switch (r) { case SSH_ERR_INTERNAL_ERROR: case SSH_ERR_ALLOC_FAIL: case SSH_ERR_SYSTEM_ERROR: case 0: return r; } /* try rsa1 public key */ if ((pub = sshkey_new(KEY_RSA1)) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_try_load_public(pub, filename, commentp)) == 0) { *keyp = pub; return 0; } sshkey_free(pub); /* try ssh2 public key */ if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_try_load_public(pub, filename, commentp)) == 0) { *keyp = pub; return 0; } skip: /* try .pub suffix */ if (pub == NULL && (pub = sshkey_new(KEY_UNSPEC)) == NULL) return SSH_ERR_ALLOC_FAIL; r = SSH_ERR_ALLOC_FAIL; /* in case strlcpy or strlcat fail */ if ((strlcpy(file, filename, sizeof file) < sizeof(file)) && (strlcat(file, ".pub", sizeof file) < sizeof(file)) && (r = sshkey_try_load_public(pub, file, commentp)) == 0) { *keyp = pub; return 0; } sshkey_free(pub); return r; } /* Load the certificate associated with the named private key */ int sshkey_load_cert(const char *filename, struct sshkey **keyp) { struct sshkey *pub = NULL; char *file = NULL; int r; *keyp = NULL; if (asprintf(&file, "%s-cert.pub", filename) == -1) return SSH_ERR_ALLOC_FAIL; if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshkey_try_load_public(pub, file, NULL)) != 0) goto out; *keyp = pub; pub = NULL; r = 0; out: if (file != NULL) free(file); if (pub != NULL) sshkey_free(pub); return r; } /* Load private key and certificate */ int sshkey_load_private_cert(int type, const char *filename, const char *passphrase, struct sshkey **keyp, int *perm_ok) { struct sshkey *key = NULL, *cert = NULL; int r; *keyp = NULL; switch (type) { case KEY_RSA: case KEY_DSA: case KEY_ECDSA: case KEY_UNSPEC: break; default: return SSH_ERR_KEY_TYPE_UNKNOWN; } if ((r = sshkey_load_private_type(type, filename, passphrase, &key, NULL, perm_ok)) != 0 || (r = sshkey_load_cert(filename, &cert)) != 0) goto out; /* Make sure the private key matches the certificate */ if (sshkey_equal_public(key, cert) == 0) { r = SSH_ERR_KEY_CERT_MISMATCH; goto out; } if ((r = sshkey_to_certified(key, sshkey_cert_is_legacy(cert))) != 0 || (r = sshkey_cert_copy(cert, key)) != 0) goto out; r = 0; *keyp = key; key = NULL; out: if (key != NULL) sshkey_free(key); if (cert != NULL) sshkey_free(cert); return r; } /* * Returns success if the specified "key" is listed in the file "filename", * SSH_ERR_KEY_NOT_FOUND: if the key is not listed or another error. * If strict_type is set then the key type must match exactly, * otherwise a comparison that ignores certficiate data is performed. */ int sshkey_in_file(struct sshkey *key, const char *filename, int strict_type) { FILE *f; char line[SSH_MAX_PUBKEY_BYTES]; char *cp; u_long linenum = 0; int r = 0; struct sshkey *pub = NULL; int (*sshkey_compare)(const struct sshkey *, const struct sshkey *) = strict_type ? sshkey_equal : sshkey_equal_public; if ((f = fopen(filename, "r")) == NULL) { if (errno == ENOENT) return SSH_ERR_KEY_NOT_FOUND; else return SSH_ERR_SYSTEM_ERROR; } 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; } if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshkey_read(pub, &cp)) != 0) goto out; if (sshkey_compare(key, pub)) { r = 0; goto out; } sshkey_free(pub); pub = NULL; } r = SSH_ERR_KEY_NOT_FOUND; out: if (pub != NULL) sshkey_free(pub); fclose(f); return r; }