diff options
Diffstat (limited to 'crypto/openssh/ssh-dss.c')
| -rw-r--r-- | crypto/openssh/ssh-dss.c | 290 |
1 files changed, 270 insertions, 20 deletions
diff --git a/crypto/openssh/ssh-dss.c b/crypto/openssh/ssh-dss.c index fddc29cc9173..aea661377f5c 100644 --- a/crypto/openssh/ssh-dss.c +++ b/crypto/openssh/ssh-dss.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssh-dss.c,v 1.39 2020/02/26 13:40:09 jsg Exp $ */ +/* $OpenBSD: ssh-dss.c,v 1.50 2024/01/11 01:45:36 djm Exp $ */ /* * Copyright (c) 2000 Markus Friedl. All rights reserved. * @@ -25,7 +25,7 @@ #include "includes.h" -#ifdef WITH_OPENSSL +#if defined(WITH_OPENSSL) && defined(WITH_DSA) #include <sys/types.h> @@ -37,7 +37,6 @@ #include <string.h> #include "sshbuf.h" -#include "compat.h" #include "ssherr.h" #include "digest.h" #define SSHKEY_INTERNAL @@ -48,9 +47,219 @@ #define INTBLOB_LEN 20 #define SIGBLOB_LEN (2*INTBLOB_LEN) -int -ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, - const u_char *data, size_t datalen, u_int compat) +static u_int +ssh_dss_size(const struct sshkey *key) +{ + const BIGNUM *dsa_p; + + if (key->dsa == NULL) + return 0; + DSA_get0_pqg(key->dsa, &dsa_p, NULL, NULL); + return BN_num_bits(dsa_p); +} + +static int +ssh_dss_alloc(struct sshkey *k) +{ + if ((k->dsa = DSA_new()) == NULL) + return SSH_ERR_ALLOC_FAIL; + return 0; +} + +static void +ssh_dss_cleanup(struct sshkey *k) +{ + DSA_free(k->dsa); + k->dsa = NULL; +} + +static int +ssh_dss_equal(const struct sshkey *a, const struct sshkey *b) +{ + const BIGNUM *dsa_p_a, *dsa_q_a, *dsa_g_a, *dsa_pub_key_a; + const BIGNUM *dsa_p_b, *dsa_q_b, *dsa_g_b, *dsa_pub_key_b; + + if (a->dsa == NULL || b->dsa == NULL) + return 0; + DSA_get0_pqg(a->dsa, &dsa_p_a, &dsa_q_a, &dsa_g_a); + DSA_get0_pqg(b->dsa, &dsa_p_b, &dsa_q_b, &dsa_g_b); + DSA_get0_key(a->dsa, &dsa_pub_key_a, NULL); + DSA_get0_key(b->dsa, &dsa_pub_key_b, NULL); + if (dsa_p_a == NULL || dsa_p_b == NULL || + dsa_q_a == NULL || dsa_q_b == NULL || + dsa_g_a == NULL || dsa_g_b == NULL || + dsa_pub_key_a == NULL || dsa_pub_key_b == NULL) + return 0; + if (BN_cmp(dsa_p_a, dsa_p_b) != 0) + return 0; + if (BN_cmp(dsa_q_a, dsa_q_b) != 0) + return 0; + if (BN_cmp(dsa_g_a, dsa_g_b) != 0) + return 0; + if (BN_cmp(dsa_pub_key_a, dsa_pub_key_b) != 0) + return 0; + return 1; +} + +static int +ssh_dss_serialize_public(const struct sshkey *key, struct sshbuf *b, + enum sshkey_serialize_rep opts) +{ + int r; + const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key; + + if (key->dsa == NULL) + return SSH_ERR_INVALID_ARGUMENT; + DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g); + DSA_get0_key(key->dsa, &dsa_pub_key, NULL); + if (dsa_p == NULL || dsa_q == NULL || + dsa_g == NULL || dsa_pub_key == NULL) + return SSH_ERR_INTERNAL_ERROR; + if ((r = sshbuf_put_bignum2(b, dsa_p)) != 0 || + (r = sshbuf_put_bignum2(b, dsa_q)) != 0 || + (r = sshbuf_put_bignum2(b, dsa_g)) != 0 || + (r = sshbuf_put_bignum2(b, dsa_pub_key)) != 0) + return r; + + return 0; +} + +static int +ssh_dss_serialize_private(const struct sshkey *key, struct sshbuf *b, + enum sshkey_serialize_rep opts) +{ + int r; + const BIGNUM *dsa_priv_key; + + DSA_get0_key(key->dsa, NULL, &dsa_priv_key); + if (!sshkey_is_cert(key)) { + if ((r = ssh_dss_serialize_public(key, b, opts)) != 0) + return r; + } + if ((r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0) + return r; + + return 0; +} + +static int +ssh_dss_generate(struct sshkey *k, int bits) +{ + DSA *private; + + if (bits != 1024) + return SSH_ERR_KEY_LENGTH; + if ((private = DSA_new()) == NULL) + return SSH_ERR_ALLOC_FAIL; + if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL, + NULL, NULL) || !DSA_generate_key(private)) { + DSA_free(private); + return SSH_ERR_LIBCRYPTO_ERROR; + } + k->dsa = private; + return 0; +} + +static int +ssh_dss_copy_public(const struct sshkey *from, struct sshkey *to) +{ + const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key; + BIGNUM *dsa_p_dup = NULL, *dsa_q_dup = NULL, *dsa_g_dup = NULL; + BIGNUM *dsa_pub_key_dup = NULL; + int r = SSH_ERR_INTERNAL_ERROR; + + DSA_get0_pqg(from->dsa, &dsa_p, &dsa_q, &dsa_g); + DSA_get0_key(from->dsa, &dsa_pub_key, NULL); + if ((dsa_p_dup = BN_dup(dsa_p)) == NULL || + (dsa_q_dup = BN_dup(dsa_q)) == NULL || + (dsa_g_dup = BN_dup(dsa_g)) == NULL || + (dsa_pub_key_dup = BN_dup(dsa_pub_key)) == NULL) { + r = SSH_ERR_ALLOC_FAIL; + goto out; + } + if (!DSA_set0_pqg(to->dsa, dsa_p_dup, dsa_q_dup, dsa_g_dup)) { + r = SSH_ERR_LIBCRYPTO_ERROR; + goto out; + } + dsa_p_dup = dsa_q_dup = dsa_g_dup = NULL; /* transferred */ + if (!DSA_set0_key(to->dsa, dsa_pub_key_dup, NULL)) { + r = SSH_ERR_LIBCRYPTO_ERROR; + goto out; + } + dsa_pub_key_dup = NULL; /* transferred */ + /* success */ + r = 0; + out: + BN_clear_free(dsa_p_dup); + BN_clear_free(dsa_q_dup); + BN_clear_free(dsa_g_dup); + BN_clear_free(dsa_pub_key_dup); + return r; +} + +static int +ssh_dss_deserialize_public(const char *ktype, struct sshbuf *b, + struct sshkey *key) +{ + int ret = SSH_ERR_INTERNAL_ERROR; + BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL, *dsa_pub_key = NULL; + + if (sshbuf_get_bignum2(b, &dsa_p) != 0 || + sshbuf_get_bignum2(b, &dsa_q) != 0 || + sshbuf_get_bignum2(b, &dsa_g) != 0 || + sshbuf_get_bignum2(b, &dsa_pub_key) != 0) { + ret = SSH_ERR_INVALID_FORMAT; + goto out; + } + if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g)) { + ret = SSH_ERR_LIBCRYPTO_ERROR; + goto out; + } + dsa_p = dsa_q = dsa_g = NULL; /* transferred */ + if (!DSA_set0_key(key->dsa, dsa_pub_key, NULL)) { + ret = SSH_ERR_LIBCRYPTO_ERROR; + goto out; + } + dsa_pub_key = NULL; /* transferred */ +#ifdef DEBUG_PK + DSA_print_fp(stderr, key->dsa, 8); +#endif + /* success */ + ret = 0; + out: + BN_clear_free(dsa_p); + BN_clear_free(dsa_q); + BN_clear_free(dsa_g); + BN_clear_free(dsa_pub_key); + return ret; +} + +static int +ssh_dss_deserialize_private(const char *ktype, struct sshbuf *b, + struct sshkey *key) +{ + int r; + BIGNUM *dsa_priv_key = NULL; + + if (!sshkey_is_cert(key)) { + if ((r = ssh_dss_deserialize_public(ktype, b, key)) != 0) + return r; + } + + if ((r = sshbuf_get_bignum2(b, &dsa_priv_key)) != 0) + return r; + if (!DSA_set0_key(key->dsa, NULL, dsa_priv_key)) { + BN_clear_free(dsa_priv_key); + return SSH_ERR_LIBCRYPTO_ERROR; + } + return 0; +} + +static int +ssh_dss_sign(struct sshkey *key, + u_char **sigp, size_t *lenp, + const u_char *data, size_t datalen, + const char *alg, const char *sk_provider, const char *sk_pin, u_int compat) { DSA_SIG *sig = NULL; const BIGNUM *sig_r, *sig_s; @@ -116,28 +325,29 @@ ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp, return ret; } -int +static int ssh_dss_verify(const struct sshkey *key, - const u_char *signature, size_t signaturelen, - const u_char *data, size_t datalen, u_int compat) + const u_char *sig, size_t siglen, + const u_char *data, size_t dlen, const char *alg, u_int compat, + struct sshkey_sig_details **detailsp) { - DSA_SIG *sig = NULL; + DSA_SIG *dsig = NULL; BIGNUM *sig_r = NULL, *sig_s = NULL; u_char digest[SSH_DIGEST_MAX_LENGTH], *sigblob = NULL; - size_t len, dlen = ssh_digest_bytes(SSH_DIGEST_SHA1); + size_t len, hlen = ssh_digest_bytes(SSH_DIGEST_SHA1); int ret = SSH_ERR_INTERNAL_ERROR; struct sshbuf *b = NULL; char *ktype = NULL; if (key == NULL || key->dsa == NULL || sshkey_type_plain(key->type) != KEY_DSA || - signature == NULL || signaturelen == 0) + sig == NULL || siglen == 0) return SSH_ERR_INVALID_ARGUMENT; - if (dlen == 0) + if (hlen == 0) return SSH_ERR_INTERNAL_ERROR; /* fetch signature */ - if ((b = sshbuf_from(signature, signaturelen)) == NULL) + if ((b = sshbuf_from(sig, siglen)) == NULL) return SSH_ERR_ALLOC_FAIL; if (sshbuf_get_cstring(b, &ktype, NULL) != 0 || sshbuf_get_string(b, &sigblob, &len) != 0) { @@ -159,7 +369,7 @@ ssh_dss_verify(const struct sshkey *key, } /* parse signature */ - if ((sig = DSA_SIG_new()) == NULL || + if ((dsig = DSA_SIG_new()) == NULL || (sig_r = BN_new()) == NULL || (sig_s = BN_new()) == NULL) { ret = SSH_ERR_ALLOC_FAIL; @@ -170,18 +380,18 @@ ssh_dss_verify(const struct sshkey *key, ret = SSH_ERR_LIBCRYPTO_ERROR; goto out; } - if (!DSA_SIG_set0(sig, sig_r, sig_s)) { + if (!DSA_SIG_set0(dsig, sig_r, sig_s)) { ret = SSH_ERR_LIBCRYPTO_ERROR; goto out; } sig_r = sig_s = NULL; /* transferred */ /* sha1 the data */ - if ((ret = ssh_digest_memory(SSH_DIGEST_SHA1, data, datalen, + if ((ret = ssh_digest_memory(SSH_DIGEST_SHA1, data, dlen, digest, sizeof(digest))) != 0) goto out; - switch (DSA_do_verify(digest, dlen, sig, key->dsa)) { + switch (DSA_do_verify(digest, hlen, dsig, key->dsa)) { case 1: ret = 0; break; @@ -195,7 +405,7 @@ ssh_dss_verify(const struct sshkey *key, out: explicit_bzero(digest, sizeof(digest)); - DSA_SIG_free(sig); + DSA_SIG_free(dsig); BN_clear_free(sig_r); BN_clear_free(sig_s); sshbuf_free(b); @@ -204,4 +414,44 @@ ssh_dss_verify(const struct sshkey *key, freezero(sigblob, len); return ret; } -#endif /* WITH_OPENSSL */ + +static const struct sshkey_impl_funcs sshkey_dss_funcs = { + /* .size = */ ssh_dss_size, + /* .alloc = */ ssh_dss_alloc, + /* .cleanup = */ ssh_dss_cleanup, + /* .equal = */ ssh_dss_equal, + /* .ssh_serialize_public = */ ssh_dss_serialize_public, + /* .ssh_deserialize_public = */ ssh_dss_deserialize_public, + /* .ssh_serialize_private = */ ssh_dss_serialize_private, + /* .ssh_deserialize_private = */ ssh_dss_deserialize_private, + /* .generate = */ ssh_dss_generate, + /* .copy_public = */ ssh_dss_copy_public, + /* .sign = */ ssh_dss_sign, + /* .verify = */ ssh_dss_verify, +}; + +const struct sshkey_impl sshkey_dss_impl = { + /* .name = */ "ssh-dss", + /* .shortname = */ "DSA", + /* .sigalg = */ NULL, + /* .type = */ KEY_DSA, + /* .nid = */ 0, + /* .cert = */ 0, + /* .sigonly = */ 0, + /* .keybits = */ 0, + /* .funcs = */ &sshkey_dss_funcs, +}; + +const struct sshkey_impl sshkey_dsa_cert_impl = { + /* .name = */ "ssh-dss-cert-v01@openssh.com", + /* .shortname = */ "DSA-CERT", + /* .sigalg = */ NULL, + /* .type = */ KEY_DSA_CERT, + /* .nid = */ 0, + /* .cert = */ 1, + /* .sigonly = */ 0, + /* .keybits = */ 0, + /* .funcs = */ &sshkey_dss_funcs, +}; + +#endif /* WITH_OPENSSL && WITH_DSA */ |