diff options
author | djm@openbsd.org <djm@openbsd.org> | 2017-12-18 02:25:15 +0000 |
---|---|---|
committer | Damien Miller <djm@mindrot.org> | 2017-12-19 15:21:37 +1100 |
commit | 04c7e28f83062dc42f2380d1bb3a6bf0190852c0 (patch) | |
tree | bc2c59d39a33aba84e0576039474668ada2546d2 /ssh-rsa.c | |
parent | 931c78dfd7fe30669681a59e536bbe66535f3ee9 (diff) | |
download | openssh-git-04c7e28f83062dc42f2380d1bb3a6bf0190852c0.tar.gz |
upstream commit
pass negotiated signing algorithm though to
sshkey_verify() and check that the negotiated algorithm matches the type in
the signature (only matters for RSA SHA1/SHA2 sigs). ok markus@
OpenBSD-Commit-ID: 735fb15bf4adc060d3bee9d047a4bcaaa81b1af9
Diffstat (limited to 'ssh-rsa.c')
-rw-r--r-- | ssh-rsa.c | 19 |
1 files changed, 13 insertions, 6 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-rsa.c,v 1.62 2017/07/01 13:50:45 djm Exp $ */ +/* $OpenBSD: ssh-rsa.c,v 1.63 2017/12/18 02:25:15 djm Exp $ */ /* * Copyright (c) 2000, 2003 Markus Friedl <markus@openbsd.org> * @@ -198,9 +198,10 @@ ssh_rsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, int ssh_rsa_verify(const struct sshkey *key, - const u_char *sig, size_t siglen, const u_char *data, size_t datalen) + const u_char *sig, size_t siglen, const u_char *data, size_t datalen, + const char *alg) { - char *ktype = NULL; + char *sigtype = NULL; int hash_alg, ret = SSH_ERR_INTERNAL_ERROR; size_t len, diff, modlen, dlen; struct sshbuf *b = NULL; @@ -215,11 +216,17 @@ ssh_rsa_verify(const struct sshkey *key, if ((b = sshbuf_from(sig, siglen)) == NULL) return SSH_ERR_ALLOC_FAIL; - if (sshbuf_get_cstring(b, &ktype, NULL) != 0) { + if (sshbuf_get_cstring(b, &sigtype, NULL) != 0) { ret = SSH_ERR_INVALID_FORMAT; goto out; } - if ((hash_alg = rsa_hash_alg_from_ident(ktype)) == -1) { + /* XXX djm: need cert types that reliably yield SHA-2 signatures */ + if (alg != NULL && strcmp(alg, sigtype) != 0 && + strcmp(alg, "ssh-rsa-cert-v01@openssh.com") != 0) { + ret = SSH_ERR_SIGNATURE_INVALID; + goto out; + } + if ((hash_alg = rsa_hash_alg_from_ident(sigtype)) == -1) { ret = SSH_ERR_KEY_TYPE_MISMATCH; goto out; } @@ -263,7 +270,7 @@ ssh_rsa_verify(const struct sshkey *key, explicit_bzero(sigblob, len); free(sigblob); } - free(ktype); + free(sigtype); sshbuf_free(b); explicit_bzero(digest, sizeof(digest)); return ret; |