crypt: Remove RC4 support.

[paraslash.git] / crypt.c

diff --git a/crypt.c b/crypt.c
index 610d2057947dba6757526127a317f8b87bf7eebc..cae47046fe0c8e3f0ebf2c1a479d3343c3955465 100644 (file)
--- a/crypt.c
+++ b/crypt.c
@@ -11,7 +11,6 @@
 #include <sys/socket.h>
 #include <openssl/rand.h>
 #include <openssl/err.h>
-#include <openssl/rc4.h>
 #include <openssl/pem.h>
 #include <openssl/sha.h>
 #include <openssl/bn.h>
@@ -23,6 +22,7 @@
 #include "crypt.h"
 #include "fd.h"
 #include "crypt_backend.h"
+#include "base64.h"
 
 struct asymmetric_key {
        RSA *rsa;
@@ -133,18 +133,25 @@ static int read_rsa_bignums(const unsigned char *blob, int blen, RSA **result)
 {
        int ret;
        RSA *rsa;
+       BIGNUM *n, *e;
        const unsigned char *p = blob, *end = blob + blen;
 
        rsa = RSA_new();
        if (!rsa)
                return -E_BIGNUM;
-       ret = read_bignum(p, end - p, &rsa->e);
+       ret = read_bignum(p, end - p, &e);
        if (ret < 0)
                goto fail;
        p += ret;
-       ret = read_bignum(p, end - p, &rsa->n);
+       ret = read_bignum(p, end - p, &n);
        if (ret < 0)
                goto fail;
+#ifdef HAVE_RSA_SET0_KEY
+       RSA_set0_key(rsa, n, e, NULL);
+#else
+       rsa->n = n;
+       rsa->e = e;
+#endif
        *result = rsa;
        return 1;
 fail:
@@ -158,7 +165,7 @@ int get_asymmetric_key(const char *key_file, int private,
        struct asymmetric_key *key = NULL;
        void *map = NULL;
        unsigned char *blob = NULL;
-       size_t map_size, blob_size, decoded_size;
+       size_t map_size, encoded_size, decoded_size;
        int ret, ret2;
        char *cp;
 
@@ -180,16 +187,11 @@ int get_asymmetric_key(const char *key_file, int private,
                goto out;
        }
        cp = map + ret;
+       encoded_size = map_size - ret;
        PARA_INFO_LOG("decoding public rsa-ssh key %s\n", key_file);
-       ret = -ERRNO_TO_PARA_ERROR(EOVERFLOW);
-       if (map_size > INT_MAX / 4)
-               goto out_unmap;
-       blob_size = 2 * map_size;
-       blob = para_malloc(blob_size);
-       ret = uudecode(cp, blob, blob_size);
+       ret = uudecode(cp, encoded_size, (char **)&blob, &decoded_size);
        if (ret < 0)
                goto out_unmap;
-       decoded_size = ret;
        ret = check_ssh_key_header(blob, decoded_size);
        if (ret < 0)
                goto out_unmap;
@@ -260,98 +262,51 @@ int pub_encrypt(struct asymmetric_key *pub, unsigned char *inbuf,
        return ret < 0? -E_ENCRYPT : ret;
 }
 
-struct aes_ctr_128_context {
-       AES_KEY key;
-       unsigned char ivec[AES_CRT128_BLOCK_SIZE];
-       unsigned char ecount[AES_CRT128_BLOCK_SIZE];
-       unsigned int num;
-};
-
 struct stream_cipher {
-       bool use_aes;
-       union {
-               RC4_KEY rc4_key;
-               struct aes_ctr_128_context aes;
-       } context;
+       EVP_CIPHER_CTX *aes;
 };
 
-struct stream_cipher *sc_new(const unsigned char *data, int len,
-               bool use_aes)
+struct stream_cipher *sc_new(const unsigned char *data, int len)
 {
-       int ret;
        struct stream_cipher *sc = para_malloc(sizeof(*sc));
-       struct aes_ctr_128_context *aes;
 
-       sc->use_aes = use_aes;
-       if (!use_aes) {
-               RC4_set_key(&sc->context.rc4_key, len, data);
-               return sc;
-       }
        assert(len >= 2 * AES_CRT128_BLOCK_SIZE);
-       aes = &sc->context.aes;
-       ret = AES_set_encrypt_key(data, AES_CRT128_BLOCK_SIZE * 8 /* bits */,
-               &aes->key);
-       assert(ret == 0);
-       memcpy(aes->ivec, data + AES_CRT128_BLOCK_SIZE, AES_CRT128_BLOCK_SIZE);
-       aes->num = 0;
+       sc->aes = EVP_CIPHER_CTX_new();
+       EVP_EncryptInit_ex(sc->aes, EVP_aes_128_ctr(), NULL, data,
+               data + AES_CRT128_BLOCK_SIZE);
        return sc;
 }
 
 void sc_free(struct stream_cipher *sc)
 {
+       if (!sc)
+               return;
+       EVP_CIPHER_CTX_free(sc->aes);
        free(sc);
 }
 
-/**
- * The RC4() implementation of openssl apparently reads and writes data in
- * blocks of 8 bytes. So we have to make sure our buffer sizes are a multiple
- * of this.
- */
-#define RC4_ALIGN 8
-
-static void rc4_crypt(RC4_KEY *key, struct iovec *src, struct iovec *dst)
-{
-       size_t len = src->iov_len, l1, l2;
-
-       assert(len > 0);
-       assert(len < ((typeof(src->iov_len))-1) / 2);
-       l1 = ROUND_DOWN(len, RC4_ALIGN);
-       l2 = ROUND_UP(len, RC4_ALIGN);
-
-       *dst = (typeof(*dst)) {
-               /* Add one for the terminating zero byte. */
-               .iov_base = para_malloc(l2 + 1),
-               .iov_len = len
-       };
-       RC4(key, l1, src->iov_base, dst->iov_base);
-       if (len > l1) {
-               unsigned char remainder[RC4_ALIGN] = "";
-               memcpy(remainder, src->iov_base + l1, len - l1);
-               RC4(key, len - l1, remainder, dst->iov_base + l1);
-       }
-       ((char *)dst->iov_base)[len] = '\0';
-}
-
-static void aes_ctr128_crypt(struct aes_ctr_128_context *aes, struct iovec *src,
+static void aes_ctr128_crypt(EVP_CIPHER_CTX *ctx, struct iovec *src,
                struct iovec *dst)
 {
-       size_t len = src->iov_len;
+       int ret, inlen = src->iov_len, outlen, tmplen;
 
        *dst = (typeof(*dst)) {
                /* Add one for the terminating zero byte. */
-               .iov_base = para_malloc(len + 1),
-               .iov_len = len
+               .iov_base = para_malloc(inlen + 1),
+               .iov_len = inlen
        };
-       AES_ctr128_encrypt(src->iov_base, dst->iov_base, len,
-               &aes->key, aes->ivec, aes->ecount, &aes->num);
-       ((char *)dst->iov_base)[len] = '\0';
+       ret = EVP_EncryptUpdate(ctx, dst->iov_base, &outlen, src->iov_base, inlen);
+       assert(ret != 0);
+       ret = EVP_EncryptFinal_ex(ctx, dst->iov_base + outlen, &tmplen);
+       assert(ret != 0);
+       outlen += tmplen;
+       ((char *)dst->iov_base)[outlen] = '\0';
+       dst->iov_len = outlen;
 }
 
 void sc_crypt(struct stream_cipher *sc, struct iovec *src, struct iovec *dst)
 {
-       if (sc->use_aes)
-               return aes_ctr128_crypt(&sc->context.aes, src, dst);
-       return rc4_crypt(&sc->context.rc4_key, src, dst);
+       return aes_ctr128_crypt(sc->aes, src, dst);
 }
 
 void hash_function(const char *data, unsigned long len, unsigned char *hash)