summaryrefslogtreecommitdiff
path: root/cipher.c
diff options
context:
space:
mode:
Diffstat (limited to 'cipher.c')
-rw-r--r--cipher.c299
1 files changed, 70 insertions, 229 deletions
diff --git a/cipher.c b/cipher.c
index 2def333b14d2..c3cd5dcf4405 100644
--- a/cipher.c
+++ b/cipher.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cipher.c,v 1.102 2016/08/03 05:41:57 djm Exp $ */
+/* $OpenBSD: cipher.c,v 1.107 2017/05/07 23:12:57 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -51,11 +51,6 @@
#include "openbsd-compat/openssl-compat.h"
-#ifdef WITH_SSH1
-extern const EVP_CIPHER *evp_ssh1_bf(void);
-extern const EVP_CIPHER *evp_ssh1_3des(void);
-extern int ssh1_3des_iv(EVP_CIPHER_CTX *, int, u_char *, int);
-#endif
struct sshcipher_ctx {
int plaintext;
@@ -68,17 +63,16 @@ struct sshcipher_ctx {
struct sshcipher {
char *name;
- int number; /* for ssh1 only */
u_int block_size;
u_int key_len;
u_int iv_len; /* defaults to block_size */
u_int auth_len;
- u_int discard_len;
u_int flags;
#define CFLAG_CBC (1<<0)
#define CFLAG_CHACHAPOLY (1<<1)
#define CFLAG_AESCTR (1<<2)
#define CFLAG_NONE (1<<3)
+#define CFLAG_INTERNAL CFLAG_NONE /* Don't use "none" for packets */
#ifdef WITH_OPENSSL
const EVP_CIPHER *(*evptype)(void);
#else
@@ -87,53 +81,32 @@ struct sshcipher {
};
static const struct sshcipher ciphers[] = {
-#ifdef WITH_SSH1
- { "des", SSH_CIPHER_DES, 8, 8, 0, 0, 0, 1, EVP_des_cbc },
- { "3des", SSH_CIPHER_3DES, 8, 16, 0, 0, 0, 1, evp_ssh1_3des },
-# ifndef OPENSSL_NO_BF
- { "blowfish", SSH_CIPHER_BLOWFISH, 8, 32, 0, 0, 0, 1, evp_ssh1_bf },
-# endif /* OPENSSL_NO_BF */
-#endif /* WITH_SSH1 */
#ifdef WITH_OPENSSL
- { "none", SSH_CIPHER_NONE, 8, 0, 0, 0, 0, 0, EVP_enc_null },
- { "3des-cbc", SSH_CIPHER_SSH2, 8, 24, 0, 0, 0, 1, EVP_des_ede3_cbc },
-# ifndef OPENSSL_NO_BF
- { "blowfish-cbc",
- SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_bf_cbc },
-# endif /* OPENSSL_NO_BF */
-# ifndef OPENSSL_NO_CAST
- { "cast128-cbc",
- SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_cast5_cbc },
-# endif /* OPENSSL_NO_CAST */
-# ifndef OPENSSL_NO_RC4
- { "arcfour", SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 0, EVP_rc4 },
- { "arcfour128", SSH_CIPHER_SSH2, 8, 16, 0, 0, 1536, 0, EVP_rc4 },
- { "arcfour256", SSH_CIPHER_SSH2, 8, 32, 0, 0, 1536, 0, EVP_rc4 },
-# endif /* OPENSSL_NO_RC4 */
- { "aes128-cbc", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 1, EVP_aes_128_cbc },
- { "aes192-cbc", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 1, EVP_aes_192_cbc },
- { "aes256-cbc", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
+ { "3des-cbc", 8, 24, 0, 0, CFLAG_CBC, EVP_des_ede3_cbc },
+ { "aes128-cbc", 16, 16, 0, 0, CFLAG_CBC, EVP_aes_128_cbc },
+ { "aes192-cbc", 16, 24, 0, 0, CFLAG_CBC, EVP_aes_192_cbc },
+ { "aes256-cbc", 16, 32, 0, 0, CFLAG_CBC, EVP_aes_256_cbc },
{ "rijndael-cbc@lysator.liu.se",
- SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
- { "aes128-ctr", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 0, EVP_aes_128_ctr },
- { "aes192-ctr", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 0, EVP_aes_192_ctr },
- { "aes256-ctr", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 0, EVP_aes_256_ctr },
+ 16, 32, 0, 0, CFLAG_CBC, EVP_aes_256_cbc },
+ { "aes128-ctr", 16, 16, 0, 0, 0, EVP_aes_128_ctr },
+ { "aes192-ctr", 16, 24, 0, 0, 0, EVP_aes_192_ctr },
+ { "aes256-ctr", 16, 32, 0, 0, 0, EVP_aes_256_ctr },
# ifdef OPENSSL_HAVE_EVPGCM
{ "aes128-gcm@openssh.com",
- SSH_CIPHER_SSH2, 16, 16, 12, 16, 0, 0, EVP_aes_128_gcm },
+ 16, 16, 12, 16, 0, EVP_aes_128_gcm },
{ "aes256-gcm@openssh.com",
- SSH_CIPHER_SSH2, 16, 32, 12, 16, 0, 0, EVP_aes_256_gcm },
+ 16, 32, 12, 16, 0, EVP_aes_256_gcm },
# endif /* OPENSSL_HAVE_EVPGCM */
-#else /* WITH_OPENSSL */
- { "aes128-ctr", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, CFLAG_AESCTR, NULL },
- { "aes192-ctr", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, CFLAG_AESCTR, NULL },
- { "aes256-ctr", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, CFLAG_AESCTR, NULL },
- { "none", SSH_CIPHER_NONE, 8, 0, 0, 0, 0, CFLAG_NONE, NULL },
-#endif /* WITH_OPENSSL */
+#else
+ { "aes128-ctr", 16, 16, 0, 0, CFLAG_AESCTR, NULL },
+ { "aes192-ctr", 16, 24, 0, 0, CFLAG_AESCTR, NULL },
+ { "aes256-ctr", 16, 32, 0, 0, CFLAG_AESCTR, NULL },
+#endif
{ "chacha20-poly1305@openssh.com",
- SSH_CIPHER_SSH2, 8, 64, 0, 16, 0, CFLAG_CHACHAPOLY, NULL },
+ 8, 64, 0, 16, CFLAG_CHACHAPOLY, NULL },
+ { "none", 8, 0, 0, 0, CFLAG_NONE, NULL },
- { NULL, SSH_CIPHER_INVALID, 0, 0, 0, 0, 0, 0, NULL }
+ { NULL, 0, 0, 0, 0, 0, NULL }
};
/*--*/
@@ -147,7 +120,7 @@ cipher_alg_list(char sep, int auth_only)
const struct sshcipher *c;
for (c = ciphers; c->name != NULL; c++) {
- if (c->number != SSH_CIPHER_SSH2)
+ if ((c->flags & CFLAG_INTERNAL) != 0)
continue;
if (auth_only && c->auth_len == 0)
continue;
@@ -203,12 +176,6 @@ cipher_ivlen(const struct sshcipher *c)
}
u_int
-cipher_get_number(const struct sshcipher *c)
-{
- return (c->number);
-}
-
-u_int
cipher_is_cbc(const struct sshcipher *c)
{
return (c->flags & CFLAG_CBC) != 0;
@@ -220,24 +187,6 @@ cipher_ctx_is_plaintext(struct sshcipher_ctx *cc)
return cc->plaintext;
}
-u_int
-cipher_ctx_get_number(struct sshcipher_ctx *cc)
-{
- return cc->cipher->number;
-}
-
-u_int
-cipher_mask_ssh1(int client)
-{
- u_int mask = 0;
- mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
- mask |= 1 << SSH_CIPHER_BLOWFISH;
- if (client) {
- mask |= 1 << SSH_CIPHER_DES;
- }
- return mask;
-}
-
const struct sshcipher *
cipher_by_name(const char *name)
{
@@ -248,16 +197,6 @@ cipher_by_name(const char *name)
return NULL;
}
-const struct sshcipher *
-cipher_by_number(int id)
-{
- const struct sshcipher *c;
- for (c = ciphers; c->name != NULL; c++)
- if (c->number == id)
- return c;
- return NULL;
-}
-
#define CIPHER_SEP ","
int
ciphers_valid(const char *names)
@@ -273,7 +212,7 @@ ciphers_valid(const char *names)
for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
(p = strsep(&cp, CIPHER_SEP))) {
c = cipher_by_name(p);
- if (c == NULL || c->number != SSH_CIPHER_SSH2) {
+ if (c == NULL || (c->flags & CFLAG_INTERNAL) != 0) {
free(cipher_list);
return 0;
}
@@ -282,38 +221,12 @@ ciphers_valid(const char *names)
return 1;
}
-/*
- * Parses the name of the cipher. Returns the number of the corresponding
- * cipher, or -1 on error.
- */
-
-int
-cipher_number(const char *name)
-{
- const struct sshcipher *c;
- if (name == NULL)
- return -1;
- for (c = ciphers; c->name != NULL; c++)
- if (strcasecmp(c->name, name) == 0)
- return c->number;
- return -1;
-}
-
-char *
-cipher_name(int id)
-{
- const struct sshcipher *c = cipher_by_number(id);
- return (c==NULL) ? "<unknown>" : c->name;
-}
-
const char *
cipher_warning_message(const struct sshcipher_ctx *cc)
{
if (cc == NULL || cc->cipher == NULL)
return NULL;
- if (cc->cipher->number == SSH_CIPHER_DES)
- return "use of DES is strongly discouraged due to "
- "cryptographic weaknesses";
+ /* XXX repurpose for CBC warning */
return NULL;
}
@@ -327,19 +240,13 @@ cipher_init(struct sshcipher_ctx **ccp, const struct sshcipher *cipher,
#ifdef WITH_OPENSSL
const EVP_CIPHER *type;
int klen;
- u_char *junk, *discard;
#endif
*ccp = NULL;
if ((cc = calloc(sizeof(*cc), 1)) == NULL)
return SSH_ERR_ALLOC_FAIL;
- if (cipher->number == SSH_CIPHER_DES) {
- if (keylen > 8)
- keylen = 8;
- }
-
- cc->plaintext = (cipher->number == SSH_CIPHER_NONE);
+ cc->plaintext = (cipher->flags & CFLAG_NONE) != 0;
cc->encrypt = do_encrypt;
if (keylen < cipher->key_len ||
@@ -353,6 +260,10 @@ cipher_init(struct sshcipher_ctx **ccp, const struct sshcipher *cipher,
ret = chachapoly_init(&cc->cp_ctx, key, keylen);
goto out;
}
+ if ((cc->cipher->flags & CFLAG_NONE) != 0) {
+ ret = 0;
+ goto out;
+ }
#ifndef WITH_OPENSSL
if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
aesctr_keysetup(&cc->ac_ctx, key, 8 * keylen, 8 * ivlen);
@@ -360,10 +271,6 @@ cipher_init(struct sshcipher_ctx **ccp, const struct sshcipher *cipher,
ret = 0;
goto out;
}
- if ((cc->cipher->flags & CFLAG_NONE) != 0) {
- ret = 0;
- goto out;
- }
ret = SSH_ERR_INVALID_ARGUMENT;
goto out;
#else /* WITH_OPENSSL */
@@ -394,23 +301,6 @@ cipher_init(struct sshcipher_ctx **ccp, const struct sshcipher *cipher,
ret = SSH_ERR_LIBCRYPTO_ERROR;
goto out;
}
-
- if (cipher->discard_len > 0) {
- if ((junk = malloc(cipher->discard_len)) == NULL ||
- (discard = malloc(cipher->discard_len)) == NULL) {
- free(junk);
- ret = SSH_ERR_ALLOC_FAIL;
- goto out;
- }
- ret = EVP_Cipher(cc->evp, discard, junk, cipher->discard_len);
- explicit_bzero(discard, cipher->discard_len);
- free(junk);
- free(discard);
- if (ret != 1) {
- ret = SSH_ERR_LIBCRYPTO_ERROR;
- goto out;
- }
- }
ret = 0;
#endif /* WITH_OPENSSL */
out:
@@ -448,6 +338,10 @@ cipher_crypt(struct sshcipher_ctx *cc, u_int seqnr, u_char *dest,
return chachapoly_crypt(&cc->cp_ctx, seqnr, dest, src,
len, aadlen, authlen, cc->encrypt);
}
+ if ((cc->cipher->flags & CFLAG_NONE) != 0) {
+ memcpy(dest, src, aadlen + len);
+ return 0;
+ }
#ifndef WITH_OPENSSL
if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
if (aadlen)
@@ -456,10 +350,6 @@ cipher_crypt(struct sshcipher_ctx *cc, u_int seqnr, u_char *dest,
dest + aadlen, len);
return 0;
}
- if ((cc->cipher->flags & CFLAG_NONE) != 0) {
- memcpy(dest, src, aadlen + len);
- return 0;
- }
return SSH_ERR_INVALID_ARGUMENT;
#else
if (authlen) {
@@ -536,28 +426,6 @@ cipher_free(struct sshcipher_ctx *cc)
}
/*
- * Selects the cipher, and keys if by computing the MD5 checksum of the
- * passphrase and using the resulting 16 bytes as the key.
- */
-int
-cipher_set_key_string(struct sshcipher_ctx **ccp,
- const struct sshcipher *cipher, const char *passphrase, int do_encrypt)
-{
- u_char digest[16];
- int r = SSH_ERR_INTERNAL_ERROR;
-
- if ((r = ssh_digest_memory(SSH_DIGEST_MD5,
- passphrase, strlen(passphrase),
- digest, sizeof(digest))) != 0)
- goto out;
-
- r = cipher_init(ccp, cipher, digest, 16, NULL, 0, do_encrypt);
- out:
- explicit_bzero(digest, sizeof(digest));
- return r;
-}
-
-/*
* Exports an IV from the sshcipher_ctx required to export the key
* state back from the unprivileged child to the privileged parent
* process.
@@ -566,19 +434,16 @@ int
cipher_get_keyiv_len(const struct sshcipher_ctx *cc)
{
const struct sshcipher *c = cc->cipher;
- int ivlen = 0;
- if (c->number == SSH_CIPHER_3DES)
- ivlen = 24;
- else if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
- ivlen = 0;
- else if ((cc->cipher->flags & CFLAG_AESCTR) != 0)
- ivlen = sizeof(cc->ac_ctx.ctr);
+ if ((c->flags & CFLAG_CHACHAPOLY) != 0)
+ return 0;
+ else if ((c->flags & CFLAG_AESCTR) != 0)
+ return sizeof(cc->ac_ctx.ctr);
#ifdef WITH_OPENSSL
- else
- ivlen = EVP_CIPHER_CTX_iv_length(cc->evp);
-#endif /* WITH_OPENSSL */
- return (ivlen);
+ return EVP_CIPHER_CTX_iv_length(cc->evp);
+#else
+ return 0;
+#endif
}
int
@@ -603,38 +468,26 @@ cipher_get_keyiv(struct sshcipher_ctx *cc, u_char *iv, u_int len)
if ((cc->cipher->flags & CFLAG_NONE) != 0)
return 0;
- switch (c->number) {
#ifdef WITH_OPENSSL
- case SSH_CIPHER_SSH2:
- case SSH_CIPHER_DES:
- case SSH_CIPHER_BLOWFISH:
- evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
- if (evplen == 0)
- return 0;
- else if (evplen < 0)
- return SSH_ERR_LIBCRYPTO_ERROR;
- if ((u_int)evplen != len)
- return SSH_ERR_INVALID_ARGUMENT;
+ evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
+ if (evplen == 0)
+ return 0;
+ else if (evplen < 0)
+ return SSH_ERR_LIBCRYPTO_ERROR;
+ if ((u_int)evplen != len)
+ return SSH_ERR_INVALID_ARGUMENT;
#ifndef OPENSSL_HAVE_EVPCTR
- if (c->evptype == evp_aes_128_ctr)
- ssh_aes_ctr_iv(cc->evp, 0, iv, len);
- else
-#endif
- if (cipher_authlen(c)) {
- if (!EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_IV_GEN,
- len, iv))
- return SSH_ERR_LIBCRYPTO_ERROR;
- } else
- memcpy(iv, cc->evp->iv, len);
- break;
+ if (c->evptype == evp_aes_128_ctr)
+ ssh_aes_ctr_iv(cc->evp, 0, iv, len);
+ else
#endif
-#ifdef WITH_SSH1
- case SSH_CIPHER_3DES:
- return ssh1_3des_iv(cc->evp, 0, iv, 24);
+ if (cipher_authlen(c)) {
+ if (!EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_IV_GEN,
+ len, iv))
+ return SSH_ERR_LIBCRYPTO_ERROR;
+ } else
+ memcpy(iv, cc->evp->iv, len);
#endif
- default:
- return SSH_ERR_INVALID_ARGUMENT;
- }
return 0;
}
@@ -651,36 +504,24 @@ cipher_set_keyiv(struct sshcipher_ctx *cc, const u_char *iv)
if ((cc->cipher->flags & CFLAG_NONE) != 0)
return 0;
- switch (c->number) {
#ifdef WITH_OPENSSL
- case SSH_CIPHER_SSH2:
- case SSH_CIPHER_DES:
- case SSH_CIPHER_BLOWFISH:
- evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
- if (evplen <= 0)
- return SSH_ERR_LIBCRYPTO_ERROR;
+ evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
+ if (evplen <= 0)
+ return SSH_ERR_LIBCRYPTO_ERROR;
#ifndef OPENSSL_HAVE_EVPCTR
- /* XXX iv arg is const, but ssh_aes_ctr_iv isn't */
- if (c->evptype == evp_aes_128_ctr)
- ssh_aes_ctr_iv(cc->evp, 1, (u_char *)iv, evplen);
- else
-#endif
- if (cipher_authlen(c)) {
- /* XXX iv arg is const, but EVP_CIPHER_CTX_ctrl isn't */
- if (!EVP_CIPHER_CTX_ctrl(cc->evp,
- EVP_CTRL_GCM_SET_IV_FIXED, -1, (void *)iv))
- return SSH_ERR_LIBCRYPTO_ERROR;
- } else
- memcpy(cc->evp->iv, iv, evplen);
- break;
+ /* XXX iv arg is const, but ssh_aes_ctr_iv isn't */
+ if (c->evptype == evp_aes_128_ctr)
+ ssh_aes_ctr_iv(cc->evp, 1, (u_char *)iv, evplen);
+ else
#endif
-#ifdef WITH_SSH1
- case SSH_CIPHER_3DES:
- return ssh1_3des_iv(cc->evp, 1, (u_char *)iv, 24);
+ if (cipher_authlen(c)) {
+ /* XXX iv arg is const, but EVP_CIPHER_CTX_ctrl isn't */
+ if (!EVP_CIPHER_CTX_ctrl(cc->evp,
+ EVP_CTRL_GCM_SET_IV_FIXED, -1, (void *)iv))
+ return SSH_ERR_LIBCRYPTO_ERROR;
+ } else
+ memcpy(cc->evp->iv, iv, evplen);
#endif
- default:
- return SSH_ERR_INVALID_ARGUMENT;
- }
return 0;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-25 17:19:59 +0000