diff options
Diffstat (limited to 'authfile.c')
| -rw-r--r-- | authfile.c | 395 |
1 files changed, 166 insertions, 229 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: authfile.c,v 1.111 2015/02/23 16:55:51 djm Exp $ */ +/* $OpenBSD: authfile.c,v 1.140 2020/04/17 07:15:11 djm Exp $ */ /* * Copyright (c) 2000, 2013 Markus Friedl. All rights reserved. * @@ -39,13 +39,12 @@ #include <limits.h> #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 "sshkey.h" #include "sshbuf.h" #include "ssherr.h" #include "krl.h" @@ -56,26 +55,19 @@ static int sshkey_save_private_blob(struct sshbuf *keybuf, const char *filename) { - int fd, oerrno; + int r; + mode_t omask; - 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)) { - oerrno = errno; - close(fd); - unlink(filename); - errno = oerrno; - return SSH_ERR_SYSTEM_ERROR; - } - close(fd); - return 0; + omask = umask(077); + r = sshbuf_write_file(filename, keybuf); + umask(omask); + return r; } int sshkey_save_private(struct sshkey *key, const char *filename, const char *passphrase, const char *comment, - int force_new_format, const char *new_format_cipher, int new_format_rounds) + int format, const char *openssh_format_cipher, int openssh_format_rounds) { struct sshbuf *keyblob = NULL; int r; @@ -83,7 +75,7 @@ sshkey_save_private(struct sshkey *key, const char *filename, if ((keyblob = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_private_to_fileblob(key, keyblob, passphrase, comment, - force_new_format, new_format_cipher, new_format_rounds)) != 0) + format, openssh_format_cipher, openssh_format_rounds)) != 0) goto out; if ((r = sshkey_save_private_blob(keyblob, filename)) != 0) goto out; @@ -93,84 +85,13 @@ sshkey_save_private(struct sshkey *key, const char *filename, return r; } -/* Load a key from a fd into a buffer */ -int -sshkey_load_file(int fd, 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: - explicit_bzero(buf, sizeof(buf)); - if (r != 0) - sshbuf_reset(blob); - return r; -} - -#ifdef WITH_SSH1 -/* - * 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, struct sshkey **keyp, char **commentp) -{ - struct sshbuf *b = NULL; - int r; - - *keyp = NULL; - if (commentp != NULL) - *commentp = NULL; - - if ((b = sshbuf_new()) == NULL) - return SSH_ERR_ALLOC_FAIL; - if ((r = sshkey_load_file(fd, b)) != 0) - goto out; - if ((r = sshkey_parse_public_rsa1_fileblob(b, keyp, commentp)) != 0) - goto out; - r = 0; - out: - sshbuf_free(b); - return r; -} -#endif /* WITH_SSH1 */ - /* XXX remove error() calls from here? */ int sshkey_perm_ok(int fd, const char *filename) { struct stat st; - if (fstat(fd, &st) < 0) + if (fstat(fd, &st) == -1) return SSH_ERR_SYSTEM_ERROR; /* * if a key owned by the user is accessed, then we check the @@ -186,56 +107,57 @@ sshkey_perm_ok(int fd, const char *filename) 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("It is required that your private key files are NOT accessible by others."); error("This private key will be ignored."); return SSH_ERR_KEY_BAD_PERMISSIONS; } return 0; } -/* 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) + struct sshkey **keyp, char **commentp) { int fd, r; - *keyp = NULL; + if (keyp != NULL) + *keyp = NULL; if (commentp != NULL) *commentp = NULL; - if ((fd = open(filename, O_RDONLY)) < 0) { - if (perm_ok != NULL) - *perm_ok = 0; + if ((fd = open(filename, O_RDONLY)) == -1) return SSH_ERR_SYSTEM_ERROR; - } - if (sshkey_perm_ok(fd, filename) != 0) { - if (perm_ok != NULL) - *perm_ok = 0; - r = SSH_ERR_KEY_BAD_PERMISSIONS; + + r = sshkey_perm_ok(fd, filename); + if (r != 0) goto out; - } - if (perm_ok != NULL) - *perm_ok = 1; r = sshkey_load_private_type_fd(fd, type, passphrase, keyp, commentp); + if (r == 0 && keyp && *keyp) + r = sshkey_set_filename(*keyp, filename); out: close(fd); return r; } int +sshkey_load_private(const char *filename, const char *passphrase, + struct sshkey **keyp, char **commentp) +{ + return sshkey_load_private_type(KEY_UNSPEC, filename, passphrase, + keyp, commentp); +} + +int sshkey_load_private_type_fd(int fd, int type, const char *passphrase, struct sshkey **keyp, char **commentp) { struct sshbuf *buffer = NULL; int r; - if ((buffer = sshbuf_new()) == NULL) { - r = SSH_ERR_ALLOC_FAIL; - goto out; - } - if ((r = sshkey_load_file(fd, buffer)) != 0 || + if (keyp != NULL) + *keyp = NULL; + if ((r = sshbuf_load_fd(fd, &buffer)) != 0 || (r = sshkey_parse_private_fileblob_type(buffer, type, passphrase, keyp, commentp)) != 0) goto out; @@ -243,61 +165,62 @@ sshkey_load_private_type_fd(int fd, int type, const char *passphrase, /* success */ r = 0; out: - if (buffer != NULL) - sshbuf_free(buffer); + sshbuf_free(buffer); return r; } -/* 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) +/* Load a pubkey from the unencrypted envelope of a new-format private key */ +static int +sshkey_load_pubkey_from_private(const char *filename, struct sshkey **pubkeyp) { struct sshbuf *buffer = NULL; + struct sshkey *pubkey = NULL; int r, fd; - *keyp = NULL; - if (commentp != NULL) - *commentp = NULL; + if (pubkeyp != NULL) + *pubkeyp = NULL; - if ((fd = open(filename, O_RDONLY)) < 0) + if ((fd = open(filename, O_RDONLY)) == -1) return SSH_ERR_SYSTEM_ERROR; - if (sshkey_perm_ok(fd, filename) != 0) { - r = SSH_ERR_KEY_BAD_PERMISSIONS; + if ((r = sshbuf_load_fd(fd, &buffer)) != 0 || + (r = sshkey_parse_pubkey_from_private_fileblob_type(buffer, + KEY_UNSPEC, &pubkey)) != 0) goto out; - } - - if ((buffer = sshbuf_new()) == NULL) { - r = SSH_ERR_ALLOC_FAIL; + if ((r = sshkey_set_filename(pubkey, filename)) != 0) goto out; + /* success */ + if (pubkeyp != NULL) { + *pubkeyp = pubkey; + pubkey = NULL; } - if ((r = sshkey_load_file(fd, buffer)) != 0 || - (r = sshkey_parse_private_fileblob(buffer, passphrase, filename, - keyp, commentp)) != 0) - goto out; r = 0; out: close(fd); - if (buffer != NULL) - sshbuf_free(buffer); + sshbuf_free(buffer); + sshkey_free(pubkey); return r; } static int -sshkey_try_load_public(struct sshkey *k, const char *filename, char **commentp) +sshkey_try_load_public(struct sshkey **kp, const char *filename, + char **commentp) { FILE *f; - char line[SSH_MAX_PUBKEY_BYTES]; - char *cp; - u_long linenum = 0; + char *line = NULL, *cp; + size_t linesize = 0; int r; + struct sshkey *k = NULL; + *kp = NULL; 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) { + if ((k = sshkey_new(KEY_UNSPEC)) == NULL) { + fclose(f); + return SSH_ERR_ALLOC_FAIL; + } + while (getline(&line, &linesize, f) != -1) { cp = line; switch (*cp) { case '#': @@ -321,82 +244,47 @@ sshkey_try_load_public(struct sshkey *k, const char *filename, char **commentp) if (*commentp == NULL) r = SSH_ERR_ALLOC_FAIL; } + /* success */ + *kp = k; + free(line); fclose(f); return r; } } } + free(k); + free(line); fclose(f); return SSH_ERR_INVALID_FORMAT; } -/* load public key from ssh v1 private or any pubkey file */ +/* load public key from any pubkey file */ int sshkey_load_public(const char *filename, struct sshkey **keyp, char **commentp) { - struct sshkey *pub = NULL; - char file[PATH_MAX]; - int r, fd; + char *pubfile = NULL; + int r; if (keyp != NULL) *keyp = NULL; if (commentp != NULL) *commentp = NULL; - /* XXX should load file once and attempt to parse each format */ - - if ((fd = open(filename, O_RDONLY)) < 0) - goto skip; -#ifdef WITH_SSH1 - /* try rsa1 private key */ - r = sshkey_load_public_rsa1(fd, keyp, commentp); - close(fd); - switch (r) { - case SSH_ERR_INTERNAL_ERROR: - case SSH_ERR_ALLOC_FAIL: - case SSH_ERR_INVALID_ARGUMENT: - case SSH_ERR_SYSTEM_ERROR: - case 0: - return r; - } -#endif /* WITH_SSH1 */ - - /* 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) { - if (keyp != NULL) - *keyp = pub; - return 0; - } - sshkey_free(pub); - -#ifdef WITH_SSH1 - /* 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) { - if (keyp != NULL) - *keyp = pub; - return 0; - } - sshkey_free(pub); -#endif /* WITH_SSH1 */ + if ((r = sshkey_try_load_public(keyp, filename, commentp)) == 0) + goto out; - skip: /* try .pub suffix */ - if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) + if (asprintf(&pubfile, "%s.pub", filename) == -1) 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) { - if (keyp != NULL) - *keyp = pub; - return 0; - } - sshkey_free(pub); + if ((r = sshkey_try_load_public(keyp, pubfile, commentp)) == 0) + goto out; + + /* finally, try to extract public key from private key file */ + if ((r = sshkey_load_pubkey_from_private(filename, keyp)) == 0) + goto out; + out: + free(pubfile); return r; } @@ -408,46 +296,37 @@ sshkey_load_cert(const char *filename, struct sshkey **keyp) char *file = NULL; int r = SSH_ERR_INTERNAL_ERROR; - *keyp = NULL; + if (keyp != NULL) + *keyp = NULL; if (asprintf(&file, "%s-cert.pub", filename) == -1) return SSH_ERR_ALLOC_FAIL; - if ((pub = sshkey_new(KEY_UNSPEC)) == NULL) { - 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); + r = sshkey_try_load_public(keyp, file, NULL); + free(file); + 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 **keyp) { struct sshkey *key = NULL, *cert = NULL; int r; - *keyp = NULL; + if (keyp != NULL) + *keyp = NULL; switch (type) { #ifdef WITH_OPENSSL case KEY_RSA: case KEY_DSA: case KEY_ECDSA: - case KEY_ED25519: #endif /* WITH_OPENSSL */ + case KEY_ED25519: + case KEY_XMSS: case KEY_UNSPEC: break; default: @@ -455,7 +334,7 @@ sshkey_load_private_cert(int type, const char *filename, const char *passphrase, } if ((r = sshkey_load_private_type(type, filename, - passphrase, &key, NULL, perm_ok)) != 0 || + passphrase, &key, NULL)) != 0 || (r = sshkey_load_cert(filename, &cert)) != 0) goto out; @@ -465,17 +344,17 @@ sshkey_load_private_cert(int type, const char *filename, const char *passphrase, goto out; } - if ((r = sshkey_to_certified(key, sshkey_cert_is_legacy(cert))) != 0 || + if ((r = sshkey_to_certified(key)) != 0 || (r = sshkey_cert_copy(cert, key)) != 0) goto out; r = 0; - *keyp = key; - key = NULL; + if (keyp != NULL) { + *keyp = key; + key = NULL; + } out: - if (key != NULL) - sshkey_free(key); - if (cert != NULL) - sshkey_free(cert); + sshkey_free(key); + sshkey_free(cert); return r; } @@ -492,19 +371,20 @@ sshkey_in_file(struct sshkey *key, const char *filename, int strict_type, int check_ca) { FILE *f; - char line[SSH_MAX_PUBKEY_BYTES]; - char *cp; - u_long linenum = 0; + char *line = NULL, *cp; + size_t linesize = 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) return SSH_ERR_SYSTEM_ERROR; - while (read_keyfile_line(f, filename, line, sizeof(line), - &linenum) != -1) { + while (getline(&line, &linesize, f) != -1) { + sshkey_free(pub); + pub = NULL; cp = line; /* Skip leading whitespace. */ @@ -523,21 +403,25 @@ sshkey_in_file(struct sshkey *key, const char *filename, int strict_type, r = SSH_ERR_ALLOC_FAIL; goto out; } - if ((r = sshkey_read(pub, &cp)) != 0) + switch (r = sshkey_read(pub, &cp)) { + case 0: + break; + case SSH_ERR_KEY_LENGTH: + continue; + default: goto out; + } if (sshkey_compare(key, pub) || (check_ca && sshkey_is_cert(key) && sshkey_compare(key->cert->signature_key, pub))) { r = 0; goto out; } - sshkey_free(pub); - pub = NULL; } r = SSH_ERR_KEY_NOT_FOUND; out: - if (pub != NULL) - sshkey_free(pub); + free(line); + sshkey_free(pub); fclose(f); return r; } @@ -576,3 +460,56 @@ sshkey_check_revoked(struct sshkey *key, const char *revoked_keys_file) } } +/* + * Advanced *cpp past the end of key options, defined as the first unquoted + * whitespace character. Returns 0 on success or -1 on failure (e.g. + * unterminated quotes). + */ +int +sshkey_advance_past_options(char **cpp) +{ + char *cp = *cpp; + int quoted = 0; + + for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) { + if (*cp == '\\' && cp[1] == '"') + cp++; /* Skip both */ + else if (*cp == '"') + quoted = !quoted; + } + *cpp = cp; + /* return failure for unterminated quotes */ + return (*cp == '\0' && quoted) ? -1 : 0; +} + +/* Save a public key */ +int +sshkey_save_public(const struct sshkey *key, const char *path, + const char *comment) +{ + int fd, oerrno; + FILE *f = NULL; + int r = SSH_ERR_INTERNAL_ERROR; + + if ((fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, 0644)) == -1) + return SSH_ERR_SYSTEM_ERROR; + if ((f = fdopen(fd, "w")) == NULL) { + r = SSH_ERR_SYSTEM_ERROR; + goto fail; + } + if ((r = sshkey_write(key, f)) != 0) + goto fail; + fprintf(f, " %s\n", comment); + if (ferror(f) || fclose(f) != 0) { + r = SSH_ERR_SYSTEM_ERROR; + fail: + oerrno = errno; + if (f != NULL) + fclose(f); + else + close(fd); + errno = oerrno; + return r; + } + return 0; +} |