thr3ads.net - openssh unix dev - [PATCH 4/3] Add test for -Z option [Apr 2020]

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Loïc

2020-Apr-25 00:58 UTC

[PATCH 1/3] Add private key protection information extraction to ssh-keygen

Add private key protection information extraction to shh-keygen using -v
option on top of -y option which is already parsing the private key.

Technically, the passphrase isn't necessary to do this, but it is the
most logical thing to do for me.

Adding this to -l option is not appropriate because fingerprinting is
using the .pub file when available.

An other idea is to add a new option, I can do it if you prefer.

Also, I'm laking information for information extraction from PEM and
PKCS8 file format, I'm OK to have a pointer to implement this correctly.

This patch is also adding a regression test for the functionnality.

---

?authfile.c??????????????????????????? |? 16 ++--
?authfile.h??????????????????????????? |?? 7 +-
?regress/Makefile????????????????????? |?? 3 +-
?regress/keygen-private-information.sh |? 81 +++++++++++++++++++++
?ssh-keygen.c????????????????????????? |? 44 +++++++----
?ssh-keysign.c???????????????????????? |?? 2 +-
?sshconnect2.c???????????????????????? |?? 2 +-
?sshd.c??????????????????????????????? |?? 2 +-
?sshkey.c????????????????????????????? | 101 +++++++++++++++++++++++---
?sshkey.h????????????????????????????? |? 14 +++-
?10 files changed, 234 insertions(+), 38 deletions(-)
?create mode 100644 regress/keygen-private-information.sh

diff --git a/authfile.c b/authfile.c
index 35ccf576c2b5..6c79369ebfc1 100644
--- a/authfile.c
+++ b/authfile.c
@@ -116,7 +116,7 @@ sshkey_perm_ok(int fd, const char *filename)
?
?int
?sshkey_load_private_type(int type, const char *filename, const char
*passphrase,
-??? struct sshkey **keyp, char **commentp)
+??? struct sshkey **keyp, char **commentp, struct sshkey_vault
**vault_infop)
?{
??? ?int fd, r;
?
@@ -124,6 +124,8 @@ sshkey_load_private_type(int type, const char
*filename, const char *passphrase,
??? ??? ?*keyp = NULL;
??? ?if (commentp != NULL)
??? ??? ?*commentp = NULL;
+?? ?if (vault_infop != NULL)
+?? ??? ?*vault_infop = NULL;
?
??? ?if ((fd = open(filename, O_RDONLY)) == -1)
??? ??? ?return SSH_ERR_SYSTEM_ERROR;
@@ -132,7 +134,7 @@ sshkey_load_private_type(int type, const char
*filename, const char *passphrase,
??? ?if (r != 0)
??? ??? ?goto out;
?
-?? ?r = sshkey_load_private_type_fd(fd, type, passphrase, keyp, commentp);
+?? ?r = sshkey_load_private_type_fd(fd, type, passphrase, keyp,
commentp, vault_infop);
??? ?if (r == 0 && keyp && *keyp)
??? ??? ?r = sshkey_set_filename(*keyp, filename);
? out:
@@ -142,15 +144,15 @@ sshkey_load_private_type(int type, const char
*filename, const char *passphrase,
?
?int
?sshkey_load_private(const char *filename, const char *passphrase,
-??? struct sshkey **keyp, char **commentp)
+??? struct sshkey **keyp, char **commentp, struct sshkey_vault
**vault_infop)
?{
??? ?return sshkey_load_private_type(KEY_UNSPEC, filename, passphrase,
-?? ???? keyp, commentp);
+?? ???? keyp, commentp, vault_infop);
?}
?
?int
?sshkey_load_private_type_fd(int fd, int type, const char *passphrase,
-??? struct sshkey **keyp, char **commentp)
+??? struct sshkey **keyp, char **commentp, struct sshkey_vault
**vault_infop)
?{
??? ?struct sshbuf *buffer = NULL;
??? ?int r;
@@ -159,7 +161,7 @@ sshkey_load_private_type_fd(int fd, int type, const
char *passphrase,
??? ??? ?*keyp = NULL;
??? ?if ((r = sshbuf_load_fd(fd, &buffer)) != 0 ||
??? ???? (r = sshkey_parse_private_fileblob_type(buffer, type,
-?? ???? passphrase, keyp, commentp)) != 0)
+?? ???? passphrase, keyp, commentp, vault_infop)) != 0)
??? ??? ?goto out;
?
??? ?/* success */
@@ -334,7 +336,7 @@ sshkey_load_private_cert(int type, const char
*filename, const char *passphrase,
??? ?}
?
??? ?if ((r = sshkey_load_private_type(type, filename,
-?? ???? passphrase, &key, NULL)) != 0 ||
+?? ???? passphrase, &key, NULL, NULL)) != 0 ||
??? ???? (r = sshkey_load_cert(filename, &cert)) != 0)
??? ??? ?goto out;
?
diff --git a/authfile.h b/authfile.h
index 1db067a813a1..85f78ac78edf 100644
--- a/authfile.h
+++ b/authfile.h
@@ -29,6 +29,7 @@
?
?struct sshbuf;
?struct sshkey;
+struct sshkey_vault;
?
?/* XXX document these */
?/* XXX some of these could probably be merged/retired */
@@ -37,13 +38,13 @@ int sshkey_save_private(struct sshkey *, const char *,
???? const char *, const char *, int, const char *, int);
?int sshkey_load_cert(const char *, struct sshkey **);
?int sshkey_load_public(const char *, struct sshkey **, char **);
-int sshkey_load_private(const char *, const char *, struct sshkey **,
char **);
+int sshkey_load_private(const char *, const char *, struct sshkey **,
char **, struct sshkey_vault **);
?int sshkey_load_private_cert(int, const char *, const char *,
???? struct sshkey **);
?int sshkey_load_private_type(int, const char *, const char *,
-??? struct sshkey **, char **);
+??? struct sshkey **, char **, struct sshkey_vault **);
?int sshkey_load_private_type_fd(int fd, int type, const char *passphrase,
-??? struct sshkey **keyp, char **commentp);
+??? struct sshkey **keyp, char **commentp, struct sshkey_vault
**vault_infop);
?int sshkey_perm_ok(int, const char *);
?int sshkey_in_file(struct sshkey *, const char *, int, int);
?int sshkey_check_revoked(struct sshkey *key, const char
*revoked_keys_file);
diff --git a/regress/Makefile b/regress/Makefile
index 62794d25fc42..ae6f4dd09edc 100644
--- a/regress/Makefile
+++ b/regress/Makefile
@@ -92,7 +92,8 @@ LTESTS= ?? ?connect \
??? ??? ?allow-deny-users \
??? ??? ?authinfo \
??? ??? ?sshsig \
-?? ??? ?keygen-comment
+?? ??? ?keygen-comment \
+??????? keygen-private-information
?
?
?INTEROP_TESTS=?? ?putty-transfer putty-ciphers putty-kex conch-ciphers
diff --git a/regress/keygen-private-information.sh
b/regress/keygen-private-information.sh
new file mode 100644
index 000000000000..a9959e919fd1
--- /dev/null
+++ b/regress/keygen-private-information.sh
@@ -0,0 +1,81 @@
+#??? Placed in the Public Domain.
+
+tid="Test information extraction from private key"
+
+check_private_key () {
+?? ?file="$1"
+?? ?format="$2"
+?? ?comment="$3"
+?? ?secret="$4"
+?? ?rounds="$5"
+
+?? ?# construct expected output in $exp file
+?? ?exp=$OBJ/$t-expected
+?? ?# default format is RFC4716
+?? ?test -z "$format" && format="RFC4716"
+?? ?# Currently PKCS8 is detected as PEM, should be fixed in ssh-keygen
+?? ?test "$format" = "PKCS8" &&
format="PEM"
+?? ?cat > $exp << EOF
+$comment
+Key protection details:
+File format: $format
+EOF
+?? ?if [ -z "$secret" -o "$format" = "PEM" ];
then
+?? ??? ?# For PEM format, passphrase is not detected yet, should be
fixed in ssh-keygen
+?? ??? ?echo "no passphrase" >> $exp
+?? ?else
+?? ??? ?cat >> $exp << EOF
+cipher: aes256-ctr
+kdf: bcrypt
+rounds: $rounds
+EOF
+?? ?fi
+
+?? ?if ! ${SSHKEYGEN} -yv -P "${secret}" -f $file > $OBJ/$t-pub ;
then
+?? ??? ?fail "ssh-keygen -y failed for $t-key"
+?? ?fi
+?? ?if ! sed '1 s/[^ ]* [^ ]* \?//' $OBJ/$t-pub > $OBJ/$t-tmp ; then
+?? ??? ?fail "sed failed for $t-key"
+?? ?fi
+?? ?if ! cmp $OBJ/$t-tmp $exp > /dev/null 2>&1; then
+?? ??? ?fail "ssh-keygen -yv output is not the expected value for
$t-key"
+?? ??? ?diff $exp $OBJ/$t-tmp
+?? ?fi
+?? ?rm -f $OBJ/$t-pub $OBJ/$t-tmp $exp
+}
+
+for fmt in '' PKCS8 PEM ; do
+?? ?for secret in '' 'secret1'; do
+?? ??? ?rounds_list="0"
+?? ??? ?test -n "$secret" -a -z "$fmt" &&
rounds_list="2 16"
+?? ??? ?for rounds in $rounds_list; do
+?? ??? ??? ?for t in $SSH_KEYTYPES; do
+?? ??? ??? ??? ?trace "generating $t key in '$fmt' format with
'$secret' passphrase and '$rounds' rounds"
+?? ??? ??? ??? ?rm -f $OBJ/$t-key*
+?? ??? ??? ??? ?oldfmt=""
+?? ??? ??? ??? ?case "$fmt" in
+?? ??? ??? ??? ?PKCS8|PEM) oldfmt=1 ;;
+?? ??? ??? ??? ?esac
+?? ??? ??? ??? ?# Some key types like ssh-ed25519 and *@openssh.com are
never
+?? ??? ??? ??? ?# stored in old formats.
+?? ??? ??? ??? ?case "$t" in
+?? ??? ??? ??? ?ssh-ed25519|*openssh.com) test -z "$oldfmt" ||
continue ;;
+?? ??? ??? ??? ?esac
+?? ??? ??? ??? ?comment="foo bar"
+?? ??? ??? ??? ?fmtarg=""
+?? ??? ??? ??? ?test -z "$fmt" || fmtarg="-m $fmt"
+?? ??? ??? ??? ?test "$rounds" = "0" || roundarg="-a
$rounds"
+?? ??? ??? ??? ?${SSHKEYGEN} $fmtarg $roundarg -N "${secret}" -C
"${comment}" \
+?? ??? ??? ??? ???? -t $t -f $OBJ/$t-key >/dev/null 2>&1 || \
+?? ??? ??? ??? ??? ?fatal "keygen of $t in format $fmt failed"
+?? ??? ??? ??? ?rm -f $OBJ/$t-key.pub # .pub file not used, remove it
to be sure it is not used
+?? ??? ??? ??? ?if [ ! -z "$oldfmt" ] ; then
+?? ??? ??? ??? ??? ?# Comment cannot be recovered from old format keys.
+?? ??? ??? ??? ??? ?comment=""
+?? ??? ??? ??? ?fi
+?? ??? ??? ??? ?check_private_key $OBJ/$t-key "${fmt}"
"${comment}"
"${secret}" "${rounds}"
+?? ??? ??? ??? ?rm -f $OBJ/$t-key*
+?? ??? ??? ?done
+?? ??? ?done
+?? ?done
+done
diff --git a/ssh-keygen.c b/ssh-keygen.c
index d50ca5f28c51..6dd17c48be5e 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -310,7 +310,7 @@ ask_filename(struct passwd *pw, const char *prompt)
?}
?
?static struct sshkey *
-load_identity(const char *filename, char **commentp)
+load_identity(const char *filename, char **commentp, struct
sshkey_vault **vault_infop)
?{
??? ?char *pass;
??? ?struct sshkey *prv;
@@ -318,7 +318,9 @@ load_identity(const char *filename, char **commentp)
?
??? ?if (commentp != NULL)
??? ??? ?*commentp = NULL;
-?? ?if ((r = sshkey_load_private(filename, "", &prv, commentp))
== 0)
+?? ?if (vault_infop != NULL)
+?? ??? ?*vault_infop = NULL;
+?? ?if ((r = sshkey_load_private(filename, "", &prv, commentp,
vault_infop)) == 0)
??? ??? ?return prv;
??? ?if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
??? ??? ?fatal("Load key \"%s\": %s", filename, ssh_err(r));
@@ -326,7 +328,7 @@ load_identity(const char *filename, char **commentp)
??? ??? ?pass = xstrdup(identity_passphrase);
??? ?else
??? ??? ?pass = read_passphrase("Enter passphrase: ", RP_ALLOW_STDIN);
-?? ?r = sshkey_load_private(filename, pass, &prv, commentp);
+?? ?r = sshkey_load_private(filename, pass, &prv, commentp, vault_infop);
??? ?freezero(pass, strlen(pass));
??? ?if (r != 0)
??? ??? ?fatal("Load key \"%s\": %s", filename, ssh_err(r));
@@ -429,7 +431,7 @@ do_convert_to(struct passwd *pw)
??? ?if (stat(identity_file, &st) == -1)
??? ??? ?fatal("%s: %s: %s", __progname, identity_file,
strerror(errno));
??? ?if ((r = sshkey_load_public(identity_file, &k, NULL)) != 0)
-?? ??? ?k = load_identity(identity_file, NULL);
+?? ??? ?k = load_identity(identity_file, NULL, NULL);
??? ?switch (convert_format) {
??? ?case FMT_RFC4716:
??? ??? ?do_convert_to_ssh2(pw, k);
@@ -806,19 +808,33 @@ do_print_public(struct passwd *pw)
??? ?struct stat st;
??? ?int r;
??? ?char *comment = NULL;
+?? ?struct sshkey_vault *vault_info = NULL;
?
??? ?if (!have_identity)
??? ??? ?ask_filename(pw, "Enter file in which the key is");
??? ?if (stat(identity_file, &st) == -1)
??? ??? ?fatal("%s: %s", identity_file, strerror(errno));
-?? ?prv = load_identity(identity_file, &comment);
+?? ?prv = load_identity(identity_file, &comment, &vault_info);
??? ?if ((r = sshkey_write(prv, stdout)) != 0)
??? ??? ?error("sshkey_write failed: %s", ssh_err(r));
??? ?sshkey_free(prv);
??? ?if (comment != NULL && *comment != '\0')
-?? ??? ?fprintf(stdout, " %s", comment);
-?? ?fprintf(stdout, "\n");
+?? ??? ?printf(" %s", comment);
+?? ?printf("\n");
+?? ?if (log_level_get() >= SYSLOG_LEVEL_VERBOSE) {
+?? ??? ?printf("Key protection details:\n");
+?? ??? ?printf("File format: %s\n",
sshkey_format_name(vault_info->format));
+?? ??? ?if ( (vault_info->ciphername == NULL ||
strcmp(vault_info->ciphername, "none") == 0)
+?? ??? ?? || (vault_info->kdfname == NULL ||
strcmp(vault_info->kdfname, "none") == 0)) {
+?? ??? ??? ?printf("no passphrase\n");
+?? ??? ?} else {
+?? ??? ??? ?printf("cipher: %s\n", vault_info->ciphername);
+?? ??? ??? ?printf("kdf: %s\n", vault_info->kdfname);
+?? ??? ??? ?printf("rounds: %d\n", vault_info->rounds);
+?? ??? ?}
+?? ?}
??? ?free(comment);
+?? ?sshkey_vault_free(vault_info);
??? ?exit(0);
?}
?
@@ -920,7 +936,7 @@ fingerprint_private(const char *path)
??? ?if (pubkey == NULL || comment == NULL || *comment == '\0') {
??? ??? ?free(comment);
??? ??? ?if ((r = sshkey_load_private(path, NULL,
-?? ??? ???? &privkey, &comment)) != 0)
+?? ??? ???? &privkey, &comment, NULL)) != 0)
??? ??? ??? ?debug("load private \"%s\": %s", path,
ssh_err(r));
??? ?}
??? ?if (pubkey == NULL && privkey == NULL)
@@ -1416,7 +1432,7 @@ do_change_passphrase(struct passwd *pw)
??? ?if (stat(identity_file, &st) == -1)
??? ??? ?fatal("%s: %s", identity_file, strerror(errno));
??? ?/* Try to load the file with empty passphrase. */
-?? ?r = sshkey_load_private(identity_file, "", &private,
&comment);
+?? ?r = sshkey_load_private(identity_file, "", &private,
&comment, NULL);
??? ?if (r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
??? ??? ?if (identity_passphrase)
??? ??? ??? ?old_passphrase = xstrdup(identity_passphrase);
@@ -1425,7 +1441,7 @@ do_change_passphrase(struct passwd *pw)
??? ??? ??? ???? read_passphrase("Enter old passphrase: ",
??? ??? ??? ???? RP_ALLOW_STDIN);
??? ??? ?r = sshkey_load_private(identity_file, old_passphrase,
-?? ??? ???? &private, &comment);
+?? ??? ???? &private, &comment, NULL);
??? ??? ?freezero(old_passphrase, strlen(old_passphrase));
??? ??? ?if (r != 0)
??? ??? ??? ?goto badkey;
@@ -1525,7 +1541,7 @@ do_change_comment(struct passwd *pw, const char
*identity_comment)
??? ?if (stat(identity_file, &st) == -1)
??? ??? ?fatal("%s: %s", identity_file, strerror(errno));
??? ?if ((r = sshkey_load_private(identity_file, "",
-?? ???? &private, &comment)) == 0)
+?? ???? &private, &comment, NULL)) == 0)
??? ??? ?passphrase = xstrdup("");
??? ?else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
??? ??? ?fatal("Cannot load private key \"%s\": %s.",
@@ -1540,7 +1556,7 @@ do_change_comment(struct passwd *pw, const char
*identity_comment)
??? ??? ??? ???? RP_ALLOW_STDIN);
??? ??? ?/* Try to load using the passphrase. */
??? ??? ?if ((r = sshkey_load_private(identity_file, passphrase,
-?? ??? ???? &private, &comment)) != 0) {
+?? ??? ???? &private, &comment, NULL)) != 0) {
??? ??? ??? ?freezero(passphrase, strlen(passphrase));
??? ??? ??? ?fatal("Cannot load private key \"%s\": %s.",
??? ??? ??? ???? identity_file, ssh_err(r));
@@ -1785,7 +1801,7 @@ do_ca_sign(struct passwd *pw, const char
*ca_key_path, int prefer_agent,
??? ??? ?ca->flags |= SSHKEY_FLAG_EXT;
??? ?} else {
??? ??? ?/* CA key is assumed to be a private key on the filesystem */
-?? ??? ?ca = load_identity(tmp, NULL);
+?? ??? ?ca = load_identity(tmp, NULL, NULL);
??? ?}
??? ?free(tmp);
?
@@ -2494,7 +2510,7 @@ load_sign_key(const char *keypath, const struct
sshkey *pubkey)
??? ??? ?debug("%s: %s looks like a public key, using private key "
??? ??? ???? "path %s instead", __func__, keypath, privpath);
??? ?}
-?? ?if ((privkey = load_identity(privpath, NULL)) == NULL) {
+?? ?if ((privkey = load_identity(privpath, NULL, NULL)) == NULL) {
??? ??? ?error("Couldn't load identity %s", keypath);
??? ??? ?goto done;
??? ?}
diff --git a/ssh-keysign.c b/ssh-keysign.c
index 3e3ea3e1481d..c9c20483b9a5 100644
--- a/ssh-keysign.c
+++ b/ssh-keysign.c
@@ -225,7 +225,7 @@ main(int argc, char **argv)
??? ??? ?if (key_fd[i] == -1)
??? ??? ??? ?continue;
??? ??? ?r = sshkey_load_private_type_fd(key_fd[i], KEY_UNSPEC,
-?? ??? ???? NULL, &key, NULL);
+?? ??? ???? NULL, &key, NULL, NULL);
??? ??? ?close(key_fd[i]);
??? ??? ?if (r != 0)
??? ??? ??? ?debug("parse key %d: %s", i, ssh_err(r));
diff --git a/sshconnect2.c b/sshconnect2.c
index 1a6545edf026..7947f2da6584 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -1472,7 +1472,7 @@ load_identity_file(Identity *id)
??? ??? ??? ?}
??? ??? ?}
??? ??? ?switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
-?? ??? ???? passphrase, &private, &comment))) {
+?? ??? ???? passphrase, &private, &comment, NULL))) {
??? ??? ?case 0:
??? ??? ??? ?break;
??? ??? ?case SSH_ERR_KEY_WRONG_PASSPHRASE:
diff --git a/sshd.c b/sshd.c
index 6f8f11a3bdac..42c19089a225 100644
--- a/sshd.c
+++ b/sshd.c
@@ -1789,7 +1789,7 @@ main(int ac, char **av)
??? ??? ?if (options.host_key_files[i] == NULL)
??? ??? ??? ?continue;
??? ??? ?if ((r = sshkey_load_private(options.host_key_files[i], "",
-?? ??? ???? &key, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
+?? ??? ???? &key, NULL, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
??? ??? ??? ?do_log2(ll, "Unable to load host key \"%s\":
%s",
??? ??? ??? ???? options.host_key_files[i], ssh_err(r));
??? ??? ?if (sshkey_is_sk(key) &&
diff --git a/sshkey.c b/sshkey.c
index 1571e3d93878..4c1948a3752e 100644
--- a/sshkey.c
+++ b/sshkey.c
@@ -93,6 +93,26 @@ int?? ?sshkey_private_serialize_opt(struct sshkey *key,
?static int sshkey_from_blob_internal(struct sshbuf *buf,
???? struct sshkey **keyp, int allow_cert);
?
+/* Supported format types */
+const char *
+sshkey_format_name(enum sshkey_private_format format) {
+?? ?const char *format_str;
+?? ?switch (format) {
+?? ?case SSHKEY_PRIVATE_OPENSSH:
+?? ??? ?format_str = "RFC4716";
+?? ??? ?break;
+?? ?case SSHKEY_PRIVATE_PKCS8:
+?? ??? ?format_str = "PKCS8";
+?? ??? ?break;
+?? ?case SSHKEY_PRIVATE_PEM:
+?? ??? ?format_str = "PEM";
+?? ??? ?break;
+?? ?default:
+?? ??? ?format_str = "unknown";
+?? ?}
+?? ?return format_str;
+}
+
?/* Supported key types */
?struct keytype {
??? ?const char *name;
@@ -679,6 +699,29 @@ sshkey_free(struct sshkey *k)
??? ?freezero(k, sizeof(*k));
?}
?
+struct sshkey_vault *
+sshkey_vault_new()
+{
+?? ?struct sshkey_vault *k = calloc(1, sizeof(*k));
+?? ?if (k == NULL)
+?? ??? ?return NULL;
+?? ?k->format = SSHKEY_PRIVATE_OPENSSH;
+?? ?k->ciphername = NULL;
+?? ?k->kdfname = NULL;
+?? ?k->rounds = -1;
+?? ?return k;
+}
+
+void
+sshkey_vault_free(struct sshkey_vault *k)
+{
+?? ?if (k == NULL)
+?? ??? ?return;
+?? ?free(k->kdfname);
+?? ?free(k);
+?? ?return;
+}
+
?static int
?cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
?{
@@ -4029,7 +4072,7 @@ private2_uudecode(struct sshbuf *blob, struct
sshbuf **decodedp)
?
?static int
?private2_decrypt(struct sshbuf *decoded, const char *passphrase,
-??? struct sshbuf **decryptedp, struct sshkey **pubkeyp)
+??? struct sshbuf **decryptedp, struct sshkey **pubkeyp, struct
sshkey_vault **vault_infop)
?{
??? ?char *ciphername = NULL, *kdfname = NULL;
??? ?const struct sshcipher *cipher = NULL;
@@ -4038,12 +4081,21 @@ private2_decrypt(struct sshbuf *decoded, const
char *passphrase,
??? ?struct sshbuf *kdf = NULL, *decrypted = NULL;
??? ?struct sshcipher_ctx *ciphercontext = NULL;
??? ?struct sshkey *pubkey = NULL;
+?? ?struct sshkey_vault *vault_info = NULL;
??? ?u_char *key = NULL, *salt = NULL, *dp;
??? ?u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
?
??? ?if (decoded == NULL || decryptedp == NULL || pubkeyp == NULL)
??? ??? ?return SSH_ERR_INVALID_ARGUMENT;
?
+?? ?if (vault_infop != NULL) {
+?? ??? ?*vault_infop = NULL;
+?? ?}
+?? ?if ((vault_info = sshkey_vault_new()) == NULL) {
+?? ??? ?r = SSH_ERR_ALLOC_FAIL;
+?? ??? ?goto out;
+?? ?}
+
??? ?*decryptedp = NULL;
??? ?*pubkeyp = NULL;
?
@@ -4074,10 +4126,18 @@ private2_decrypt(struct sshbuf *decoded, const
char *passphrase,
??? ??? ?r = SSH_ERR_KEY_UNKNOWN_CIPHER;
??? ??? ?goto out;
??? ?}
+?? ?if ((vault_info->ciphername = strdup(ciphername)) == NULL) {
+?? ??? ?r = SSH_ERR_ALLOC_FAIL;
+?? ??? ?goto out;
+?? ?}
??? ?if (strcmp(kdfname, "none") != 0 && strcmp(kdfname,
"bcrypt") != 0) {
??? ??? ?r = SSH_ERR_KEY_UNKNOWN_CIPHER;
??? ??? ?goto out;
??? ?}
+?? ?if ((vault_info->kdfname = strdup(kdfname)) == NULL) {
+?? ??? ?r = SSH_ERR_ALLOC_FAIL;
+?? ??? ?goto out;
+?? ?}
??? ?if (strcmp(kdfname, "none") == 0 && strcmp(ciphername,
"none") != 0) {
??? ??? ?r = SSH_ERR_INVALID_FORMAT;
??? ??? ?goto out;
@@ -4108,6 +4168,7 @@ private2_decrypt(struct sshbuf *decoded, const
char *passphrase,
??? ??? ?if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
??? ??? ???? (r = sshbuf_get_u32(kdf, &rounds)) != 0)
??? ??? ??? ?goto out;
+?? ??? ?vault_info->rounds = rounds;
??? ??? ?if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
??? ??? ???? key, keylen + ivlen, rounds) < 0) {
??? ??? ??? ?r = SSH_ERR_INVALID_FORMAT;
@@ -4155,6 +4216,10 @@ private2_decrypt(struct sshbuf *decoded, const
char *passphrase,
??? ?decrypted = NULL;
??? ?*pubkeyp = pubkey;
??? ?pubkey = NULL;
+?? ?if (vault_infop != NULL) {
+?? ??? ?*vault_infop = vault_info;
+?? ??? ?vault_info = NULL;
+?? ?}
??? ?r = 0;
? out:
??? ?cipher_free(ciphercontext);
@@ -4171,6 +4236,7 @@ private2_decrypt(struct sshbuf *decoded, const
char *passphrase,
??? ?}
??? ?sshbuf_free(kdf);
??? ?sshbuf_free(decrypted);
+?? ?sshkey_vault_free(vault_info);
??? ?return r;
?}
?
@@ -4201,7 +4267,7 @@ private2_check_padding(struct sshbuf *decrypted)
?
?static int
?sshkey_parse_private2(struct sshbuf *blob, int type, const char
*passphrase,
-??? struct sshkey **keyp, char **commentp)
+??? struct sshkey **keyp, char **commentp, struct sshkey_vault
**vault_infop)
?{
??? ?char *comment = NULL;
??? ?int r = SSH_ERR_INTERNAL_ERROR;
@@ -4216,7 +4282,7 @@ sshkey_parse_private2(struct sshbuf *blob, int
type, const char *passphrase,
??? ?/* Undo base64 encoding and decrypt the private section */
??? ?if ((r = private2_uudecode(blob, &decoded)) != 0 ||
??? ???? (r = private2_decrypt(decoded, passphrase,
-?? ???? &decrypted, &pubkey)) != 0)
+?? ???? &decrypted, &pubkey, vault_infop)) != 0)
??? ??? ?goto out;
?
??? ?if (type != KEY_UNSPEC &&
@@ -4521,15 +4587,18 @@ pem_passphrase_cb(char *buf, int size, int
rwflag, void *u)
?
?static int
?sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
-??? const char *passphrase, struct sshkey **keyp)
+??? const char *passphrase, struct sshkey **keyp, struct sshkey_vault
**vault_infop)
?{
??? ?EVP_PKEY *pk = NULL;
??? ?struct sshkey *prv = NULL;
+?? ?struct sshkey_vault *vault_info = NULL;
??? ?BIO *bio = NULL;
??? ?int r;
?
??? ?if (keyp != NULL)
??? ??? ?*keyp = NULL;
+?? ?if (vault_infop != NULL)
+?? ??? ?*vault_infop = NULL;
?
??? ?if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
??? ??? ?return SSH_ERR_ALLOC_FAIL;
@@ -4538,6 +4607,13 @@ sshkey_parse_private_pem_fileblob(struct sshbuf
*blob, int type,
??? ??? ?r = SSH_ERR_ALLOC_FAIL;
??? ??? ?goto out;
??? ?}
+?? ?if ((vault_info = sshkey_vault_new()) == NULL) {
+?? ??? ?r = SSH_ERR_ALLOC_FAIL;
+?? ??? ?goto out;
+?? ?}
+?? ?// TODO: identify correctly PEM and PKCS8 format
+?? ?vault_info->format = SSHKEY_PRIVATE_PEM;
+?? ?// TODO: put the correct ciphername, kdfname and round if a
passphrase is used
?
??? ?clear_libcrypto_errors();
??? ?if ((pk = PEM_read_bio_PrivateKey(bio, NULL, pem_passphrase_cb,
@@ -4614,17 +4690,22 @@ sshkey_parse_private_pem_fileblob(struct sshbuf
*blob, int type,
??? ??? ?*keyp = prv;
??? ??? ?prv = NULL;
??? ?}
+?? ?if (vault_infop != NULL) {
+?? ??? ?*vault_infop = vault_info;
+?? ??? ?vault_info = NULL;
+?? ?}
? out:
??? ?BIO_free(bio);
??? ?EVP_PKEY_free(pk);
??? ?sshkey_free(prv);
+?? ?sshkey_vault_free(vault_info);
??? ?return r;
?}
?#endif /* WITH_OPENSSL */
?
?int
?sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
-??? const char *passphrase, struct sshkey **keyp, char **commentp)
+??? const char *passphrase, struct sshkey **keyp, char **commentp,
struct sshkey_vault **vault_infop)
?{
??? ?int r = SSH_ERR_INTERNAL_ERROR;
?
@@ -4632,22 +4713,24 @@ sshkey_parse_private_fileblob_type(struct sshbuf
*blob, int type,
??? ??? ?*keyp = NULL;
??? ?if (commentp != NULL)
??? ??? ?*commentp = NULL;
+?? ?if (vault_infop != NULL)
+?? ??? ?*vault_infop = NULL;
?
??? ?switch (type) {
??? ?case KEY_ED25519:
??? ?case KEY_XMSS:
??? ??? ?/* No fallback for new-format-only keys */
??? ??? ?return sshkey_parse_private2(blob, type, passphrase,
-?? ??? ???? keyp, commentp);
+?? ??? ???? keyp, commentp, vault_infop);
??? ?default:
??? ??? ?r = sshkey_parse_private2(blob, type, passphrase, keyp,
-?? ??? ???? commentp);
+?? ??? ???? commentp, vault_infop);
??? ??? ?/* Only fallback to PEM parser if a format error occurred. */
??? ??? ?if (r != SSH_ERR_INVALID_FORMAT)
??? ??? ??? ?return r;
?#ifdef WITH_OPENSSL
??? ??? ?return sshkey_parse_private_pem_fileblob(blob, type,
-?? ??? ???? passphrase, keyp);
+?? ??? ???? passphrase, keyp, vault_infop);
?#else
??? ??? ?return SSH_ERR_INVALID_FORMAT;
?#endif /* WITH_OPENSSL */
@@ -4664,7 +4747,7 @@ sshkey_parse_private_fileblob(struct sshbuf
*buffer, const char *passphrase,
??? ??? ?*commentp = NULL;
?
??? ?return sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
-?? ???? passphrase, keyp, commentp);
+?? ???? passphrase, keyp, commentp, NULL);
?}
?
?void
diff --git a/sshkey.h b/sshkey.h
index 9c1d4f6372f6..7b7de828d9ce 100644
--- a/sshkey.h
+++ b/sshkey.h
@@ -99,6 +99,8 @@ enum sshkey_private_format {
??? ?SSHKEY_PRIVATE_PEM = 1,
??? ?SSHKEY_PRIVATE_PKCS8 = 2,
?};
+const char *
+sshkey_format_name(enum sshkey_private_format);
?
?/* key is stored in external hardware */
?#define SSHKEY_FLAG_EXT?? ??? ?0x0001
@@ -162,6 +164,16 @@ struct sshkey_sig_details {
??? ?uint8_t sk_flags;?? ?/* U2F signature flags; see ssh-sk.h */
?};
?
+/* Key storage parameters in private key file */
+struct sshkey_vault {
+?? ?enum sshkey_private_format format;
+?? ?char *ciphername;
+?? ?char *kdfname;
+?? ?int rounds;
+};
+struct sshkey_vault?? ?*sshkey_vault_new();
+void?? ??? ?sshkey_vault_free(struct sshkey_vault *);
+
?struct sshkey?? ?*sshkey_new(int);
?void?? ??? ? sshkey_free(struct sshkey *);
?int?? ??? ? sshkey_equal_public(const struct sshkey *,
@@ -258,7 +270,7 @@ int?? ?sshkey_private_to_fileblob(struct sshkey
*key, struct sshbuf *blob,
?int?? ?sshkey_parse_private_fileblob(struct sshbuf *buffer,
???? const char *passphrase, struct sshkey **keyp, char **commentp);
?int?? ?sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
-??? const char *passphrase, struct sshkey **keyp, char **commentp);
+??? const char *passphrase, struct sshkey **keyp, char **commentp,
struct sshkey_vault **vault_infop);
?int?? ?sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
???? int type, struct sshkey **pubkeyp);
?
-- 
2.17.1

Loïc

2020-Apr-25 21:35 UTC

head link

[PATCH 4/3] Add test for -Z option

On 25/04/2020 at 02:58, Lo?c wrote :> Add private key protection information extraction to shh-keygen using -v
> option on top of -y option which is already parsing the private key.
>
> Technically, the passphrase isn't necessary to do this, but it is the
> most logical thing to do for me.
>
> Adding this to -l option is not appropriate because fingerprinting is
> using the .pub file when available.
>
> An other idea is to add a new option, I can do it if you prefer.
>
> Also, I'm laking information for information extraction from PEM and
> PKCS8 file format, I'm OK to have a pointer to implement this
correctly.
>
> This patch is also adding a regression test for the functionnality.
>
> ---
>
> ?authfile.c??????????????????????????? |? 16 ++--
> ?authfile.h??????????????????????????? |?? 7 +-
> ?regress/Makefile????????????????????? |?? 3 +-
> ?regress/keygen-private-information.sh |? 81 +++++++++++++++++++++
> ?ssh-keygen.c????????????????????????? |? 44 +++++++----
> ?ssh-keysign.c???????????????????????? |?? 2 +-
> ?sshconnect2.c???????????????????????? |?? 2 +-
> ?sshd.c??????????????????????????????? |?? 2 +-
> ?sshkey.c????????????????????????????? | 101 +++++++++++++++++++++++---
> ?sshkey.h????????????????????????????? |? 14 +++-
> ?10 files changed, 234 insertions(+), 38 deletions(-)
> ?create mode 100644 regress/keygen-private-information.sh
>In since I discovered the -Z option, I'm adding here a regression test
for this option, the patch below applies on top on the upper one I'm
replying to.

Hope it is useful.

---
?regress/keygen-private-information.sh | 82 ++++++++++++++++-----------
?1 file changed, 50 insertions(+), 32 deletions(-)

diff --git a/regress/keygen-private-information.sh
b/regress/keygen-private-information.sh
index a9959e919fd1..ddf74eb95c3c 100644
--- a/regress/keygen-private-information.sh
+++ b/regress/keygen-private-information.sh
@@ -7,7 +7,8 @@ check_private_key () {
???? format="$2"
???? comment="$3"
???? secret="$4"
-??? rounds="$5"
+??? cipher="$5"
+??? rounds="$6"
?
???? # construct expected output in $exp file
???? exp=$OBJ/$t-expected
@@ -25,7 +26,7 @@ EOF
???? ??? echo "no passphrase" >> $exp
???? else
???? ??? cat >> $exp << EOF
-cipher: aes256-ctr
+cipher: $cipher
?kdf: bcrypt
?rounds: $rounds
?EOF
@@ -44,37 +45,54 @@ EOF
???? rm -f $OBJ/$t-pub $OBJ/$t-tmp $exp
?}
?
-for fmt in '' PKCS8 PEM ; do
+for fmt in '' RFC4716 PKCS8 PEM ; do
???? for secret in '' 'secret1'; do
-??? ??? rounds_list="0"
-??? ??? test -n "$secret" -a -z "$fmt" &&
rounds_list="2 16"
-??? ??? for rounds in $rounds_list; do
-??? ??? ??? for t in $SSH_KEYTYPES; do
-??? ??? ??? ??? trace "generating $t key in '$fmt' format with
'$secret' passphrase and '$rounds' rounds"
-??? ??? ??? ??? rm -f $OBJ/$t-key*
-??? ??? ??? ??? oldfmt=""
-??? ??? ??? ??? case "$fmt" in
-??? ??? ??? ??? PKCS8|PEM) oldfmt=1 ;;
-??? ??? ??? ??? esac
-??? ??? ??? ??? # Some key types like ssh-ed25519 and *@openssh.com are
never
-??? ??? ??? ??? # stored in old formats.
-??? ??? ??? ??? case "$t" in
-??? ??? ??? ??? ssh-ed25519|*openssh.com) test -z "$oldfmt" ||
continue ;;
-??? ??? ??? ??? esac
-??? ??? ??? ??? comment="foo bar"
-??? ??? ??? ??? fmtarg=""
-??? ??? ??? ??? test -z "$fmt" || fmtarg="-m $fmt"
-??? ??? ??? ??? test "$rounds" = "0" || roundarg="-a
$rounds"
-??? ??? ??? ??? ${SSHKEYGEN} $fmtarg $roundarg -N "${secret}" -C
"${comment}" \
-??? ??? ??? ??? ??? -t $t -f $OBJ/$t-key >/dev/null 2>&1 || \
-??? ??? ??? ??? ??? fatal "keygen of $t in format $fmt failed"
-??? ??? ??? ??? rm -f $OBJ/$t-key.pub # .pub file not used, remove it
to be sure it is not used
-??? ??? ??? ??? if [ ! -z "$oldfmt" ] ; then
-??? ??? ??? ??? ??? # Comment cannot be recovered from old format keys.
-??? ??? ??? ??? ??? comment=""
-??? ??? ??? ??? fi
-??? ??? ??? ??? check_private_key $OBJ/$t-key "${fmt}"
"${comment}"
"${secret}" "${rounds}"
-??? ??? ??? ??? rm -f $OBJ/$t-key*
+??? ??? cipher_list="default"
+??? ??? test -n "$secret" -a -z "$fmt" &&
cipher_list=`${SSH} -Q cipher`
+??? ??? for cipher in $cipher_list; do
+??? ??? ??? rounds_list="default"
+??? ??? ??? test -n "$secret" -a -z "$fmt" &&
rounds_list="2 16"
+??? ??? ??? for rounds in $rounds_list; do
+??? ??? ??? ??? for t in $SSH_KEYTYPES; do
+??? ??? ??? ??? ??? trace "generating $t key in '$fmt' format with
'$secret' passphrase, '$cipher' cipher and '$rounds'
rounds"
+??? ??? ??? ??? ??? rm -f $OBJ/$t-key*
+??? ??? ??? ??? ??? oldfmt=""
+??? ??? ??? ??? ??? case "$fmt" in
+??? ??? ??? ??? ??? PKCS8|PEM) oldfmt=1 ;;
+??? ??? ??? ??? ??? esac
+??? ??? ??? ??? ??? # Some key types like ssh-ed25519 and *@openssh.com
are never
+??? ??? ??? ??? ??? # stored in old formats.
+??? ??? ??? ??? ??? case "$t" in
+??? ??? ??? ??? ??? ssh-ed25519|*openssh.com) test -z "$oldfmt" ||
continue ;;
+??? ??? ??? ??? ??? esac
+??? ??? ??? ??? ??? comment="foo bar"
+??? ??? ??? ??? ??? fmtarg=""
+??? ??? ??? ??? ??? test -z "$fmt" || fmtarg="-m $fmt"
+??? ??? ??? ??? ??? if test "$rounds" = "default" ; then
+??? ??? ??? ??? ??? ??? rounds=16;
+??? ??? ??? ??? ??? ??? roundarg=""
+??? ??? ??? ??? ??? else
+??? ??? ??? ??? ??? ??? roundarg="-a $rounds";
+??? ??? ??? ??? ??? fi
+??? ??? ??? ??? ??? if test "$cipher" = "default" ; then
+??? ??? ??? ??? ??? ??? cipher="aes256-ctr" ;
+??? ??? ??? ??? ??? ??? cipherarg=""
+??? ??? ??? ??? ??? else
+??? ??? ??? ??? ??? ??? cipherarg="-Z $cipher";
+??? ??? ??? ??? ??? fi
+??? ??? ??? ??? ??? ${SSHKEYGEN} $fmtarg $cipherarg $roundarg \
+??? ??? ??? ??? ??? ??? -N "${secret}" -C "${comment}" \
+??? ??? ??? ??? ??? ??? -t $t -f $OBJ/$t-key >/dev/null 2>&1 || \
+??? ??? ??? ??? ??? ??? fatal "keygen of $t in format $fmt failed"
+??? ??? ??? ??? ??? rm -f $OBJ/$t-key.pub # .pub file not used, remove
it to be sure it is not used
+??? ??? ??? ??? ??? if [ ! -z "$oldfmt" ] ; then
+??? ??? ??? ??? ??? ??? # Comment cannot be recovered from old format keys.
+??? ??? ??? ??? ??? ??? comment=""
+??? ??? ??? ??? ??? fi
+??? ??? ??? ??? ??? check_private_key $OBJ/$t-key "${fmt}"
"${comment}" \
+??? ??? ??? ??? ??? ??? "${secret}" "${cipher}"
"${rounds}"
+??? ??? ??? ??? ??? rm -f $OBJ/$t-key*
+??? ??? ??? ??? done
???? ??? ??? done
???? ??? done
???? done
-- 
2.17.1

Loïc

2020-Apr-25 21:48 UTC

head link

[PATCH 5/3] ssh-keygen: -Z cipher can be "none" test it in regression and, report it correctly in -yv option

On 25/04/2020 at 23:35, Lo?c wrote :> On 25/04/2020 at 02:58, Lo?c wrote :
>> Add private key protection information extraction to shh-keygen using
-v
>> option on top of -y option which is already parsing the private key.
>>
>> Technically, the passphrase isn't necessary to do this, but it is
the
>> most logical thing to do for me.
>>
>> Adding this to -l option is not appropriate because fingerprinting is
>> using the .pub file when available.
>>
>> An other idea is to add a new option, I can do it if you prefer.
>>
>> Also, I'm laking information for information extraction from PEM
and
>> PKCS8 file format, I'm OK to have a pointer to implement this
correctly.
>>
>> This patch is also adding a regression test for the functionnality.
>>
>> ---
>>
>> ?authfile.c??????????????????????????? |? 16 ++--
>> ?authfile.h??????????????????????????? |?? 7 +-
>> ?regress/Makefile????????????????????? |?? 3 +-
>> ?regress/keygen-private-information.sh |? 81 +++++++++++++++++++++
>> ?ssh-keygen.c????????????????????????? |? 44 +++++++----
>> ?ssh-keysign.c???????????????????????? |?? 2 +-
>> ?sshconnect2.c???????????????????????? |?? 2 +-
>> ?sshd.c??????????????????????????????? |?? 2 +-
>> ?sshkey.c????????????????????????????? | 101 +++++++++++++++++++++++---
>> ?sshkey.h????????????????????????????? |? 14 +++-
>> ?10 files changed, 234 insertions(+), 38 deletions(-)
>> ?create mode 100644 regress/keygen-private-information.sh
>>
> In since I discovered the -Z option, I'm adding here a regression test
> for this option, the patch below applies on top on the upper one I'm
> replying to.
>In fact "none" cypher is allowed here is a patch to test it in
regression and report it correctly in -yv option

---
?regress/keygen-private-information.sh | 2 +-
?ssh-keygen.c????????????????????????? | 3 +--
?2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/regress/keygen-private-information.sh
b/regress/keygen-private-information.sh
index ddf74eb95c3c..22ad6429a079 100644
--- a/regress/keygen-private-information.sh
+++ b/regress/keygen-private-information.sh
@@ -48,7 +48,7 @@ EOF
?for fmt in '' RFC4716 PKCS8 PEM ; do
???? for secret in '' 'secret1'; do
???? ??? cipher_list="default"
-??? ??? test -n "$secret" -a -z "$fmt" &&
cipher_list=`${SSH} -Q cipher`
+??? ??? test -n "$secret" -a -z "$fmt" &&
cipher_list=`${SSH} -Q
cipher`" none"
???? ??? for cipher in $cipher_list; do
???? ??? ??? rounds_list="default"
???? ??? ??? test -n "$secret" -a -z "$fmt" &&
rounds_list="2 16"
diff --git a/ssh-keygen.c b/ssh-keygen.c
index a848edc33b5d..030b12e5b897 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -824,8 +824,7 @@ do_print_public(struct passwd *pw)
???? if (log_level_get() >= SYSLOG_LEVEL_VERBOSE) {
???? ??? printf("Key protection details:\n");
???? ??? printf("File format: %s\n",
sshkey_format_name(vault_info->format));
-??? ??? if ( (vault_info->ciphername == NULL ||
strcmp(vault_info->ciphername, "none") == 0)
-??? ??? ? || (vault_info->kdfname == NULL ||
strcmp(vault_info->kdfname, "none") == 0)) {
+??? ??? if (vault_info->kdfname == NULL || strcmp(vault_info->kdfname,
"none") == 0) {
???? ??? ??? printf("no passphrase\n");
???? ??? } else {
???? ??? ??? printf("cipher: %s\n", vault_info->ciphername);
-- 
2.17.1

openssh unix dev - Apr 2020 - [PATCH 4/3] Add test for -Z option

[PATCH 1/3] Add private key protection information extraction to ssh-keygen

[PATCH 4/3] Add test for -Z option

[PATCH 5/3] ssh-keygen: -Z cipher can be "none" test it in regression and, report it correctly in -yv option