WIP: Adds MbedTLS support to Cytoplasm #54

Draft
lda wants to merge 9 commits from lda/Cytoplasm:add-mbed into master
8 changed files with 451 additions and 3 deletions

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@ -5,6 +5,20 @@ Cytoplasm. It is intended to be updated with every commit that makes a user-faci
change worth reporting in the change log. As such, it changes frequently between
releases. Final change log entries are published as [Releases](releases).
## v0.5.0
**TO BE WRITTEN**
### Breaking Changes
- `ShaToHex` now requires what hash was used.
### New Features
- LMDB support is available with the `--with-lmdb` flag.
- MbedTLS summort is available with the `--with-mbed` flag. Please note that Cytoplasm
programs using it must be used with the `CYTO_TLS_CA` environment defined to map to a
valid CA file, and that the `CYTO_TLS_SEED` flag can be set to use a seedfile, increasing
entropy on systems where it is unavailable.
## v0.4.1
Cytoplasm is now a C99 library! Upgrading from C89 to C99 makes Cytoplasm more portable

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@ -21,6 +21,7 @@ Cytoplasm aims to have zero software dependencies beyond what is mandated by POS
- OpenSSL
- LibreSSL
- MbedTLS (requires the `CYTO_TLS_CA` environment variables for programs built with it)
If TLS support is not enabled, all APIs that use it should fall back to non-TLS behavior in a sensible manner. For example, if TLS support is not enabled, then the HTTP client API will simply return an error if a TLS connection is requested.
@ -50,7 +51,7 @@ You can also run `make install` as `root` to install Cytoplasm to the system. Th
The `configure` script has a number of optional flags, which are as follows:
- `--with-(openssl|libressl)`: Select the TLS implementation to use. OpenSSL is selected by default.
- `--with-(openssl|libressl|mbed)`: Select the TLS implementation to use. OpenSSL is selected by default.
- `--disable-tls`: Disable TLS altogether.
- `--prefix=<path>`: Set the install prefix to set by default in the `Makefile`. This defaults to `/usr/local`, which should be appropriate for most Unix-like systems.
- `--(enable|disable)-debug`: Control whether or not to enable debug mode. This sets the optimization level to 0 and builds with debug symbols. Useful for running with a debugger.
@ -113,4 +114,4 @@ Note that both arguments to Main may be treated like any other Cytoplasm array o
All of the code and documentation for Cytoplasm is licensed under the same license as Telodendria itself. Please refer to [Telodendria &rightarrow; License](/Telodendria/Telodendria#license) for details.
The Cytoplasm logo was designed by [Tobskep](https://tobskep.com) and is licensed under the [Creative Commons Attribution-ShareAlike 4.0](https://creativecommons.org/licenses/by-sa/4.0/) license.
The Cytoplasm logo was designed by [Tobskep](https://tobskep.com) and is licensed under the [Creative Commons Attribution-ShareAlike 4.0](https://creativecommons.org/licenses/by-sa/4.0/) license.

4
configure vendored
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@ -76,6 +76,10 @@ for arg in $SCRIPT_ARGS; do
TLS_IMPL="TLS_LIBRESSL"
TLS_LIBS="-ltls -lcrypto -lssl"
;;
--with-mbed)
TLS_IMPL="TLS_MBEDTLS"
TLS_LIBS="-lmbedtls -lmbedx509 -lmbedcrypto"
;;
--disable-tls)
TLS_IMPL=""
TLS_LIBS=""

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@ -50,6 +50,7 @@
#define TLS_LIBRESSL 2
#define TLS_OPENSSL 3
#define TLS_MBEDTLS 4
/**
* Create a new TLS client stream using the given file descriptor and

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@ -29,6 +29,7 @@
#include <limits.h>
/* TODO: Verify LibreSSL support later */
#include <Tls.h>
#if defined(TLS_IMPL) && (TLS_IMPL == TLS_OPENSSL)
#include <openssl/sha.h>

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@ -31,6 +31,7 @@
/* TODO: Verify LibreSSL support later */
#include <Tls.h>
#if defined(TLS_IMPL) && (TLS_IMPL == TLS_OPENSSL)
#include <openssl/sha.h>

426
src/Tls/TlsMbedTLS.c Normal file
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@ -0,0 +1,426 @@
/*
* Copyright (C) 2022-2024 Jordan Bancino <@jordan:bancino.net> with
* other valuable contributors. See CONTRIBUTORS.txt for the full list.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <Tls.h>
#if TLS_IMPL == TLS_MBEDTLS
#include "mbedtls/net_sockets.h"
#include "mbedtls/ssl.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/debug.h"
#include "mbedtls/error.h"
#include <Memory.h>
#include <Log.h>
#include <Str.h>
#include <string.h>
#include <stdlib.h>
/*
* #include statements and any implementation structures
* needed should go here.
*/
typedef struct MbedCookie {
int fd;
bool serverside;
mbedtls_net_context serverFD;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctrDrbg;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_x509_crt cert;
mbedtls_pk_context serverkey;
} MbedCookie;
static bool
AddPEM(mbedtls_x509_crt *certs, char *path)
{
size_t len;
if (!certs || !path)
{
return false;
}
len = strlen(path);
if (len >= 4 && StrEquals(&path[len - 1 - 4], ".pem"))
{
/* Parse it as a file */
if (mbedtls_x509_crt_parse_file(certs, path) == 0)
{
return true;
}
}
/* Parse it as a directory if it is not a .PEM
* Note that this is non-recursive. */
return mbedtls_x509_crt_parse_path(certs, path) == 0;
}
static bool
RegisterPEMs(mbedtls_x509_crt *certs)
{
char *cafile;
int loaded = 0;
if (!certs)
{
return false;
}
/* Step 0: Load from CYTO_TLS_CA if present to overwrite */
cafile = getenv("CYTO_TLS_CA");
if (AddPEM(certs, cafile))
{
loaded++;
}
/* Step 1: Try /etc/ssl/certs */
if (AddPEM(certs, "/etc/ssl/certs"))
{
loaded++;
}
/* Step 2: Try loading off Mozilla's certificates */
if (AddPEM(certs, "/usr/share/ca-certificates/mozilla"))
{
loaded++;
}
/* Step 3: Try loading from its root directly */
if (AddPEM(certs, "/usr/share/ca-certificates"))
{
loaded++;
}
return loaded != 0;
}
void *
TlsInitClient(int fd, const char *serverName)
{
MbedCookie *cookie;
int err;
if (!serverName)
{
return NULL;
}
cookie = Malloc(sizeof(MbedCookie));
memset(cookie, 0, sizeof(MbedCookie));
cookie->fd = fd;
cookie->serverside = false;
/* Initialise MbedTLS */
mbedtls_net_init(&cookie->serverFD);
mbedtls_ssl_init(&cookie->ssl);
mbedtls_ssl_config_init(&cookie->conf);
mbedtls_x509_crt_init(&cookie->cert);
mbedtls_ctr_drbg_init(&cookie->ctrDrbg);
mbedtls_pk_init(&cookie->serverkey);
mbedtls_entropy_init(&cookie->entropy);
err = mbedtls_ctr_drbg_seed(
&cookie->ctrDrbg,
mbedtls_entropy_func,
&cookie->entropy,
(const unsigned char *) serverName, strlen(serverName)
);
if (err != 0)
{
Log(LOG_ERR, "MbedTLS failure on client init: %d", err);
goto error;
}
cookie->serverFD.fd = fd;
err = mbedtls_ssl_config_defaults(
&cookie->conf,
MBEDTLS_SSL_IS_CLIENT,
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT
);
if (err != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on client config: %s", message);
goto error;
}
/* Setup key verification */
if (!RegisterPEMs(&cookie->cert))
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on client certs: %s", message);
goto error;
}
mbedtls_ssl_conf_authmode(&cookie->conf, MBEDTLS_SSL_VERIFY_REQUIRED);
mbedtls_ssl_conf_ca_chain(&cookie->conf, &cookie->cert, NULL);
/* Setup some callbacks */
mbedtls_ssl_conf_rng(
&cookie->conf,
mbedtls_ctr_drbg_random,
&cookie->ctrDrbg
);
if ((err = mbedtls_ssl_setup(&cookie->ssl, &cookie->conf)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on SSL setup: %s", message);
goto error;
}
/* Setup some functions */
mbedtls_ssl_set_bio(
&cookie->ssl, &cookie->serverFD,
mbedtls_net_send, mbedtls_net_recv, NULL
);
/* Setup the servername */
if ((err = mbedtls_ssl_set_hostname(&cookie->ssl, serverName)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on client hostname: %s", message);
goto error;
}
while ((err = mbedtls_ssl_handshake(&cookie->ssl)) != 0)
{
char message[256];
switch (err)
{
case MBEDTLS_ERR_SSL_WANT_WRITE:
case MBEDTLS_ERR_SSL_WANT_READ:
break;
default:
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on handshake: %s", message);
goto error;
}
}
return cookie;
error:
mbedtls_net_free(&cookie->serverFD);
mbedtls_ssl_free(&cookie->ssl);
mbedtls_ssl_config_free(&cookie->conf);
mbedtls_ctr_drbg_free(&cookie->ctrDrbg);
mbedtls_entropy_free(&cookie->entropy);
Free(cookie);
return NULL;
}
void *
TlsInitServer(int fd, const char *crt, const char *key)
{
MbedCookie *cookie;
char *seed;
int err;
if (!crt || !key)
{
return NULL;
}
cookie = Malloc(sizeof(MbedCookie));
memset(cookie, 0, sizeof(MbedCookie));
cookie->fd = fd;
cookie->serverside = true;
/* Initialise MbedTLS */
mbedtls_net_init(&cookie->serverFD);
mbedtls_ssl_init(&cookie->ssl);
mbedtls_ssl_config_init(&cookie->conf);
mbedtls_x509_crt_init(&cookie->cert);
mbedtls_ctr_drbg_init(&cookie->ctrDrbg);
mbedtls_pk_init(&cookie->serverkey);
mbedtls_entropy_init(&cookie->entropy);
err = mbedtls_ctr_drbg_seed(
&cookie->ctrDrbg,
mbedtls_entropy_func,
&cookie->entropy,
(const unsigned char *) key, strlen(key)
);
if (err != 0)
{
Log(LOG_ERR, "MbedTLS failure on server init: %d", err);
goto error;
}
/* Add a source of entropy if possible(using the CYTO_TLS_SEED env).
* Note that we ignore the error code. */
seed = getenv("CYTO_TLS_SEED");
mbedtls_entropy_update_seed_file(&cookie->entropy, seed);
/* Setup key verification */
if ((err = mbedtls_x509_crt_parse_file(&cookie->cert, crt)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on server certs: %s", message);
goto error;
}
if ((err = mbedtls_pk_parse_keyfile(&cookie->serverkey, key, NULL, mbedtls_entropy_func, &cookie->ctrDrbg)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on server certs: %s", message);
goto error;
}
mbedtls_ssl_conf_ca_chain(&cookie->conf, cookie->cert.next, NULL);
if ((err = mbedtls_ssl_conf_own_cert(&cookie->conf, &cookie->cert, &cookie->serverkey)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on server certs: %s", message);
goto error;
}
/* Setup SSL */
cookie->serverFD.fd = fd;
err = mbedtls_ssl_config_defaults(
&cookie->conf,
MBEDTLS_SSL_IS_SERVER,
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT
);
if (err != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on server SSL: %s", message);
goto error;
}
/* Setup some callbacks */
mbedtls_ssl_conf_rng(
&cookie->conf,
mbedtls_ctr_drbg_random,
&cookie->ctrDrbg
);
mbedtls_ssl_conf_ca_chain(&cookie->conf, cookie->cert.next, NULL);
if ((err = mbedtls_ssl_setup(&cookie->ssl, &cookie->conf)) != 0)
{
char message[256];
mbedtls_strerror(err, message, 255);
Log(LOG_ERR, "MbedTLS failure on SSL setup: %s", message);
goto error;
}
/* Client connexion */
/* Setup some functions */
mbedtls_ssl_set_bio(
&cookie->ssl, &cookie->serverFD,
mbedtls_net_send, mbedtls_net_recv, NULL
);
/* Handshake the client */
while ((err = mbedtls_ssl_handshake(&cookie->ssl)) != 0)
{
switch (err)
{
case MBEDTLS_ERR_SSL_WANT_WRITE:
case MBEDTLS_ERR_SSL_WANT_READ:
break;
default:
goto error;
}
}
return cookie;
error:
mbedtls_net_free(&cookie->serverFD);
mbedtls_ssl_free(&cookie->ssl);
mbedtls_ssl_config_free(&cookie->conf);
mbedtls_ctr_drbg_free(&cookie->ctrDrbg);
mbedtls_entropy_free(&cookie->entropy);
Free(cookie);
return NULL;
}
ssize_t
TlsRead(void *cookie, void *buf, size_t nBytes)
{
MbedCookie *cooked = cookie;
int ret;
if (!cookie || !buf)
{
return -1;
}
ret = mbedtls_ssl_read(&cooked->ssl, buf, nBytes);
if (ret <= 0)
{
ret = -1;
}
return ret;
}
ssize_t
TlsWrite(void *cookie, void *buf, size_t nBytes)
{
MbedCookie *cooked = cookie;
int ret;
if (!cookie || !buf)
{
return -1;
}
ret = mbedtls_ssl_write(&cooked->ssl, buf, nBytes);
if (ret <= 0)
{
ret = -1;
}
return ret;
}
int
TlsClose(void *cookie)
{
MbedCookie *cooked = cookie;
if (!cookie)
{
return -1;
}
mbedtls_net_free(&cooked->serverFD);
mbedtls_ssl_free(&cooked->ssl);
mbedtls_ssl_config_free(&cooked->conf);
mbedtls_ctr_drbg_free(&cooked->ctrDrbg);
mbedtls_entropy_free(&cooked->entropy);
mbedtls_x509_crt_free(&cooked->cert);
if (cooked->serverside)
{
mbedtls_pk_free(&cooked->serverkey);
}
Free(cooked);
return 0;
}
#endif

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@ -399,7 +399,7 @@ end_loop:
}
else if (StrEquals(op, "def?"))
{
Definition *def;
Definition *def = NULL;
size_t i;
char *directive = Eval(&argv, stack);