upstream: Add a sshkey_check_rsa_length() call for checking the

length of an RSA key; ok markus@

OpenBSD-Commit-ID: de77cd5b11594297eda82edc594b0d32b8535134
This commit is contained in:
djm@openbsd.org 2022-09-17 10:30:45 +00:00 committed by Damien Miller
parent 3991a0cf94
commit 07d8771bac
No known key found for this signature in database
2 changed files with 18 additions and 11 deletions

View File

@ -1,4 +1,4 @@
/* $OpenBSD: sshkey.c,v 1.121 2022/05/05 01:04:14 djm Exp $ */
/* $OpenBSD: sshkey.c,v 1.122 2022/09/17 10:30:45 djm Exp $ */
/*
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
* Copyright (c) 2008 Alexander von Gernler. All rights reserved.
@ -2365,18 +2365,24 @@ cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
return ret;
}
#ifdef WITH_OPENSSL
static int
check_rsa_length(const RSA *rsa)
int
sshkey_check_rsa_length(const struct sshkey *k, int min_size)
{
#ifdef WITH_OPENSSL
const BIGNUM *rsa_n;
int nbits;
RSA_get0_key(rsa, &rsa_n, NULL, NULL);
if (BN_num_bits(rsa_n) < SSH_RSA_MINIMUM_MODULUS_SIZE)
if (k == NULL || k->rsa == NULL ||
(k->type != KEY_RSA && k->type != KEY_RSA_CERT))
return 0;
RSA_get0_key(k->rsa, &rsa_n, NULL, NULL);
nbits = BN_num_bits(rsa_n);
if (nbits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
(min_size > 0 && nbits < min_size))
return SSH_ERR_KEY_LENGTH;
#endif /* WITH_OPENSSL */
return 0;
}
#endif
static int
sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
@ -2439,7 +2445,7 @@ sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
goto out;
}
rsa_n = rsa_e = NULL; /* transferred */
if ((ret = check_rsa_length(key->rsa)) != 0)
if ((ret = sshkey_check_rsa_length(key, 0)) != 0)
goto out;
#ifdef DEBUG_PK
RSA_print_fp(stderr, key->rsa, 8);
@ -3642,7 +3648,7 @@ sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
goto out;
}
rsa_p = rsa_q = NULL; /* transferred */
if ((r = check_rsa_length(k->rsa)) != 0)
if ((r = sshkey_check_rsa_length(k, 0)) != 0)
goto out;
if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0)
goto out;
@ -4644,7 +4650,7 @@ sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
r = SSH_ERR_LIBCRYPTO_ERROR;
goto out;
}
if ((r = check_rsa_length(prv->rsa)) != 0)
if ((r = sshkey_check_rsa_length(prv, 0)) != 0)
goto out;
} else if (EVP_PKEY_base_id(pk) == EVP_PKEY_DSA &&
(type == KEY_UNSPEC || type == KEY_DSA)) {

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@ -1,4 +1,4 @@
/* $OpenBSD: sshkey.h,v 1.51 2022/01/06 22:05:42 djm Exp $ */
/* $OpenBSD: sshkey.h,v 1.52 2022/09/17 10:30:45 djm Exp $ */
/*
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
@ -273,6 +273,7 @@ int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
int type, struct sshkey **pubkeyp);
int sshkey_check_rsa_length(const struct sshkey *, int);
/* XXX should be internal, but used by ssh-keygen */
int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *);