mbedtls/programs/ssl/ssl_mail_client.c
Gilles Peskine 449bd8303e Switch to the new code style
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2023-01-11 14:50:10 +01:00

804 lines
25 KiB
C

/*
* SSL client for SMTP servers
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* Enable definition of gethostname() even when compiling with -std=c99. Must
* be set before mbedtls_config.h, which pulls in glibc's features.h indirectly.
* Harmless on other platforms. */
#define _POSIX_C_SOURCE 200112L
#define _XOPEN_SOURCE 600
#include "mbedtls/build_info.h"
#include "mbedtls/platform.h"
#if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) || \
!defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_CLI_C) || \
!defined(MBEDTLS_NET_C) || !defined(MBEDTLS_RSA_C) || \
!defined(MBEDTLS_CTR_DRBG_C) || !defined(MBEDTLS_X509_CRT_PARSE_C) || \
!defined(MBEDTLS_FS_IO)
int main(void)
{
mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
"MBEDTLS_SSL_TLS_C and/or MBEDTLS_SSL_CLI_C and/or "
"MBEDTLS_NET_C and/or MBEDTLS_RSA_C and/or "
"MBEDTLS_CTR_DRBG_C and/or MBEDTLS_X509_CRT_PARSE_C "
"not defined.\n");
mbedtls_exit(0);
}
#else
#include "mbedtls/base64.h"
#include "mbedtls/error.h"
#include "mbedtls/net_sockets.h"
#include "mbedtls/ssl.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "test/certs.h"
#include "mbedtls/x509.h"
#include <stdlib.h>
#include <string.h>
#if !defined(_MSC_VER) || defined(EFIX64) || defined(EFI32)
#include <unistd.h>
#else
#include <io.h>
#endif
#if defined(_WIN32) || defined(_WIN32_WCE)
#include <winsock2.h>
#include <windows.h>
#if defined(_MSC_VER)
#if defined(_WIN32_WCE)
#pragma comment( lib, "ws2.lib" )
#else
#pragma comment( lib, "ws2_32.lib" )
#endif
#endif /* _MSC_VER */
#endif
#define DFL_SERVER_NAME "localhost"
#define DFL_SERVER_PORT "465"
#define DFL_USER_NAME "user"
#define DFL_USER_PWD "password"
#define DFL_MAIL_FROM ""
#define DFL_MAIL_TO ""
#define DFL_DEBUG_LEVEL 0
#define DFL_CA_FILE ""
#define DFL_CRT_FILE ""
#define DFL_KEY_FILE ""
#define DFL_FORCE_CIPHER 0
#define DFL_MODE 0
#define DFL_AUTHENTICATION 0
#define MODE_SSL_TLS 0
#define MODE_STARTTLS 0
#if defined(MBEDTLS_BASE64_C)
#define USAGE_AUTH \
" authentication=%%d default: 0 (disabled)\n" \
" user_name=%%s default: \"" DFL_USER_NAME "\"\n" \
" user_pwd=%%s default: \"" \
DFL_USER_PWD "\"\n"
#else
#define USAGE_AUTH \
" authentication options disabled. (Require MBEDTLS_BASE64_C)\n"
#endif /* MBEDTLS_BASE64_C */
#if defined(MBEDTLS_FS_IO)
#define USAGE_IO \
" ca_file=%%s default: \"\" (pre-loaded)\n" \
" crt_file=%%s default: \"\" (pre-loaded)\n" \
" key_file=%%s default: \"\" (pre-loaded)\n"
#else
#define USAGE_IO \
" No file operations available (MBEDTLS_FS_IO not defined)\n"
#endif /* MBEDTLS_FS_IO */
#define USAGE \
"\n usage: ssl_mail_client param=<>...\n" \
"\n acceptable parameters:\n" \
" server_name=%%s default: " DFL_SERVER_NAME "\n" \
" server_port=%%d default: " \
DFL_SERVER_PORT "\n" \
" debug_level=%%d default: 0 (disabled)\n" \
" mode=%%d default: 0 (SSL/TLS) (1 for STARTTLS)\n" \
USAGE_AUTH \
" mail_from=%%s default: \"\"\n" \
" mail_to=%%s default: \"\"\n" \
USAGE_IO \
" force_ciphersuite=<name> default: all enabled\n" \
" acceptable ciphersuite names:\n"
/*
* global options
*/
struct options {
const char *server_name; /* hostname of the server (client only) */
const char *server_port; /* port on which the ssl service runs */
int debug_level; /* level of debugging */
int authentication; /* if authentication is required */
int mode; /* SSL/TLS (0) or STARTTLS (1) */
const char *user_name; /* username to use for authentication */
const char *user_pwd; /* password to use for authentication */
const char *mail_from; /* E-Mail address to use as sender */
const char *mail_to; /* E-Mail address to use as recipient */
const char *ca_file; /* the file with the CA certificate(s) */
const char *crt_file; /* the file with the client certificate */
const char *key_file; /* the file with the client key */
int force_ciphersuite[2]; /* protocol/ciphersuite to use, or all */
} opt;
static void my_debug(void *ctx, int level,
const char *file, int line,
const char *str)
{
((void) level);
mbedtls_fprintf((FILE *) ctx, "%s:%04d: %s", file, line, str);
fflush((FILE *) ctx);
}
static int do_handshake(mbedtls_ssl_context *ssl)
{
int ret;
uint32_t flags;
unsigned char buf[1024];
memset(buf, 0, 1024);
/*
* 4. Handshake
*/
mbedtls_printf(" . Performing the SSL/TLS handshake...");
fflush(stdout);
while ((ret = mbedtls_ssl_handshake(ssl)) != 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
#if defined(MBEDTLS_ERROR_C)
mbedtls_strerror(ret, (char *) buf, 1024);
#endif
mbedtls_printf(" failed\n ! mbedtls_ssl_handshake returned %d: %s\n\n", ret, buf);
return -1;
}
}
mbedtls_printf(" ok\n [ Ciphersuite is %s ]\n",
mbedtls_ssl_get_ciphersuite(ssl));
/*
* 5. Verify the server certificate
*/
mbedtls_printf(" . Verifying peer X.509 certificate...");
/* In real life, we probably want to bail out when ret != 0 */
if ((flags = mbedtls_ssl_get_verify_result(ssl)) != 0) {
#if !defined(MBEDTLS_X509_REMOVE_INFO)
char vrfy_buf[512];
#endif
mbedtls_printf(" failed\n");
#if !defined(MBEDTLS_X509_REMOVE_INFO)
mbedtls_x509_crt_verify_info(vrfy_buf, sizeof(vrfy_buf), " ! ", flags);
mbedtls_printf("%s\n", vrfy_buf);
#endif
} else {
mbedtls_printf(" ok\n");
}
#if !defined(MBEDTLS_X509_REMOVE_INFO)
mbedtls_printf(" . Peer certificate information ...\n");
mbedtls_x509_crt_info((char *) buf, sizeof(buf) - 1, " ",
mbedtls_ssl_get_peer_cert(ssl));
mbedtls_printf("%s\n", buf);
#endif
return 0;
}
static int write_ssl_data(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
{
int ret;
mbedtls_printf("\n%s", buf);
while (len && (ret = mbedtls_ssl_write(ssl, buf, len)) <= 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
mbedtls_printf(" failed\n ! mbedtls_ssl_write returned %d\n\n", ret);
return -1;
}
}
return 0;
}
static int write_ssl_and_get_response(mbedtls_ssl_context *ssl, unsigned char *buf, size_t len)
{
int ret;
unsigned char data[128];
char code[4];
size_t i, idx = 0;
mbedtls_printf("\n%s", buf);
while (len && (ret = mbedtls_ssl_write(ssl, buf, len)) <= 0) {
if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
mbedtls_printf(" failed\n ! mbedtls_ssl_write returned %d\n\n", ret);
return -1;
}
}
do {
len = sizeof(data) - 1;
memset(data, 0, sizeof(data));
ret = mbedtls_ssl_read(ssl, data, len);
if (ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
continue;
}
if (ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY) {
return -1;
}
if (ret <= 0) {
mbedtls_printf("failed\n ! mbedtls_ssl_read returned %d\n\n", ret);
return -1;
}
mbedtls_printf("\n%s", data);
len = ret;
for (i = 0; i < len; i++) {
if (data[i] != '\n') {
if (idx < 4) {
code[idx++] = data[i];
}
continue;
}
if (idx == 4 && code[0] >= '0' && code[0] <= '9' && code[3] == ' ') {
code[3] = '\0';
return atoi(code);
}
idx = 0;
}
} while (1);
}
static int write_and_get_response(mbedtls_net_context *sock_fd, unsigned char *buf, size_t len)
{
int ret;
unsigned char data[128];
char code[4];
size_t i, idx = 0;
mbedtls_printf("\n%s", buf);
if (len && (ret = mbedtls_net_send(sock_fd, buf, len)) <= 0) {
mbedtls_printf(" failed\n ! mbedtls_net_send returned %d\n\n", ret);
return -1;
}
do {
len = sizeof(data) - 1;
memset(data, 0, sizeof(data));
ret = mbedtls_net_recv(sock_fd, data, len);
if (ret <= 0) {
mbedtls_printf("failed\n ! mbedtls_net_recv returned %d\n\n", ret);
return -1;
}
data[len] = '\0';
mbedtls_printf("\n%s", data);
len = ret;
for (i = 0; i < len; i++) {
if (data[i] != '\n') {
if (idx < 4) {
code[idx++] = data[i];
}
continue;
}
if (idx == 4 && code[0] >= '0' && code[0] <= '9' && code[3] == ' ') {
code[3] = '\0';
return atoi(code);
}
idx = 0;
}
} while (1);
}
int main(int argc, char *argv[])
{
int ret = 1, len;
int exit_code = MBEDTLS_EXIT_FAILURE;
mbedtls_net_context server_fd;
#if defined(MBEDTLS_BASE64_C)
unsigned char base[1024];
/* buf is used as the destination buffer for printing base with the format:
* "%s\r\n". Hence, the size of buf should be at least the size of base
* plus 2 bytes for the \r and \n characters.
*/
unsigned char buf[sizeof(base) + 2];
#else
unsigned char buf[1024];
#endif
char hostname[32];
const char *pers = "ssl_mail_client";
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_ssl_context ssl;
mbedtls_ssl_config conf;
mbedtls_x509_crt cacert;
mbedtls_x509_crt clicert;
mbedtls_pk_context pkey;
int i;
size_t n;
char *p, *q;
const int *list;
/*
* Make sure memory references are valid in case we exit early.
*/
mbedtls_net_init(&server_fd);
mbedtls_ssl_init(&ssl);
mbedtls_ssl_config_init(&conf);
memset(&buf, 0, sizeof(buf));
mbedtls_x509_crt_init(&cacert);
mbedtls_x509_crt_init(&clicert);
mbedtls_pk_init(&pkey);
mbedtls_ctr_drbg_init(&ctr_drbg);
if (argc == 0) {
usage:
mbedtls_printf(USAGE);
list = mbedtls_ssl_list_ciphersuites();
while (*list) {
mbedtls_printf(" %s\n", mbedtls_ssl_get_ciphersuite_name(*list));
list++;
}
mbedtls_printf("\n");
goto exit;
}
opt.server_name = DFL_SERVER_NAME;
opt.server_port = DFL_SERVER_PORT;
opt.debug_level = DFL_DEBUG_LEVEL;
opt.authentication = DFL_AUTHENTICATION;
opt.mode = DFL_MODE;
opt.user_name = DFL_USER_NAME;
opt.user_pwd = DFL_USER_PWD;
opt.mail_from = DFL_MAIL_FROM;
opt.mail_to = DFL_MAIL_TO;
opt.ca_file = DFL_CA_FILE;
opt.crt_file = DFL_CRT_FILE;
opt.key_file = DFL_KEY_FILE;
opt.force_ciphersuite[0] = DFL_FORCE_CIPHER;
for (i = 1; i < argc; i++) {
p = argv[i];
if ((q = strchr(p, '=')) == NULL) {
goto usage;
}
*q++ = '\0';
if (strcmp(p, "server_name") == 0) {
opt.server_name = q;
} else if (strcmp(p, "server_port") == 0) {
opt.server_port = q;
} else if (strcmp(p, "debug_level") == 0) {
opt.debug_level = atoi(q);
if (opt.debug_level < 0 || opt.debug_level > 65535) {
goto usage;
}
} else if (strcmp(p, "authentication") == 0) {
opt.authentication = atoi(q);
if (opt.authentication < 0 || opt.authentication > 1) {
goto usage;
}
} else if (strcmp(p, "mode") == 0) {
opt.mode = atoi(q);
if (opt.mode < 0 || opt.mode > 1) {
goto usage;
}
} else if (strcmp(p, "user_name") == 0) {
opt.user_name = q;
} else if (strcmp(p, "user_pwd") == 0) {
opt.user_pwd = q;
} else if (strcmp(p, "mail_from") == 0) {
opt.mail_from = q;
} else if (strcmp(p, "mail_to") == 0) {
opt.mail_to = q;
} else if (strcmp(p, "ca_file") == 0) {
opt.ca_file = q;
} else if (strcmp(p, "crt_file") == 0) {
opt.crt_file = q;
} else if (strcmp(p, "key_file") == 0) {
opt.key_file = q;
} else if (strcmp(p, "force_ciphersuite") == 0) {
opt.force_ciphersuite[0] = -1;
opt.force_ciphersuite[0] = mbedtls_ssl_get_ciphersuite_id(q);
if (opt.force_ciphersuite[0] <= 0) {
goto usage;
}
opt.force_ciphersuite[1] = 0;
} else {
goto usage;
}
}
/*
* 0. Initialize the RNG and the session data
*/
mbedtls_printf("\n . Seeding the random number generator...");
fflush(stdout);
mbedtls_entropy_init(&entropy);
if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
(const unsigned char *) pers,
strlen(pers))) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
/*
* 1.1. Load the trusted CA
*/
mbedtls_printf(" . Loading the CA root certificate ...");
fflush(stdout);
#if defined(MBEDTLS_FS_IO)
if (strlen(opt.ca_file)) {
ret = mbedtls_x509_crt_parse_file(&cacert, opt.ca_file);
} else
#endif
#if defined(MBEDTLS_PEM_PARSE_C)
ret = mbedtls_x509_crt_parse(&cacert, (const unsigned char *) mbedtls_test_cas_pem,
mbedtls_test_cas_pem_len);
#else
{
mbedtls_printf("MBEDTLS_PEM_PARSE_C not defined.");
goto exit;
}
#endif
if (ret < 0) {
mbedtls_printf(" failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok (%d skipped)\n", ret);
/*
* 1.2. Load own certificate and private key
*
* (can be skipped if client authentication is not required)
*/
mbedtls_printf(" . Loading the client cert. and key...");
fflush(stdout);
#if defined(MBEDTLS_FS_IO)
if (strlen(opt.crt_file)) {
ret = mbedtls_x509_crt_parse_file(&clicert, opt.crt_file);
} else
#endif
ret = mbedtls_x509_crt_parse(&clicert, (const unsigned char *) mbedtls_test_cli_crt,
mbedtls_test_cli_crt_len);
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret);
goto exit;
}
#if defined(MBEDTLS_FS_IO)
if (strlen(opt.key_file)) {
ret = mbedtls_pk_parse_keyfile(&pkey, opt.key_file, "",
mbedtls_ctr_drbg_random, &ctr_drbg);
} else
#endif
#if defined(MBEDTLS_PEM_PARSE_C)
{
ret = mbedtls_pk_parse_key(&pkey,
(const unsigned char *) mbedtls_test_cli_key,
mbedtls_test_cli_key_len,
NULL,
0,
mbedtls_ctr_drbg_random,
&ctr_drbg);
}
#else
{
mbedtls_printf("MBEDTLS_PEM_PARSE_C not defined.");
goto exit;
}
#endif
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_pk_parse_key returned %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
/*
* 2. Start the connection
*/
mbedtls_printf(" . Connecting to tcp/%s/%s...", opt.server_name,
opt.server_port);
fflush(stdout);
if ((ret = mbedtls_net_connect(&server_fd, opt.server_name,
opt.server_port, MBEDTLS_NET_PROTO_TCP)) != 0) {
mbedtls_printf(" failed\n ! mbedtls_net_connect returned %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
/*
* 3. Setup stuff
*/
mbedtls_printf(" . Setting up the SSL/TLS structure...");
fflush(stdout);
if ((ret = mbedtls_ssl_config_defaults(&conf,
MBEDTLS_SSL_IS_CLIENT,
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT)) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ssl_config_defaults returned %d\n\n", ret);
goto exit;
}
/* OPTIONAL is not optimal for security,
* but makes interop easier in this simplified example */
mbedtls_ssl_conf_authmode(&conf, MBEDTLS_SSL_VERIFY_OPTIONAL);
mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);
if (opt.force_ciphersuite[0] != DFL_FORCE_CIPHER) {
mbedtls_ssl_conf_ciphersuites(&conf, opt.force_ciphersuite);
}
mbedtls_ssl_conf_ca_chain(&conf, &cacert, NULL);
if ((ret = mbedtls_ssl_conf_own_cert(&conf, &clicert, &pkey)) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ssl_conf_own_cert returned %d\n\n", ret);
goto exit;
}
if ((ret = mbedtls_ssl_setup(&ssl, &conf)) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ssl_setup returned %d\n\n", ret);
goto exit;
}
if ((ret = mbedtls_ssl_set_hostname(&ssl, opt.server_name)) != 0) {
mbedtls_printf(" failed\n ! mbedtls_ssl_set_hostname returned %d\n\n", ret);
goto exit;
}
mbedtls_ssl_set_bio(&ssl, &server_fd, mbedtls_net_send, mbedtls_net_recv, NULL);
mbedtls_printf(" ok\n");
if (opt.mode == MODE_SSL_TLS) {
if (do_handshake(&ssl) != 0) {
goto exit;
}
mbedtls_printf(" > Get header from server:");
fflush(stdout);
ret = write_ssl_and_get_response(&ssl, buf, 0);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write EHLO to server:");
fflush(stdout);
gethostname(hostname, 32);
len = sprintf((char *) buf, "EHLO %s\r\n", hostname);
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
} else {
mbedtls_printf(" > Get header from server:");
fflush(stdout);
ret = write_and_get_response(&server_fd, buf, 0);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write EHLO to server:");
fflush(stdout);
gethostname(hostname, 32);
len = sprintf((char *) buf, "EHLO %s\r\n", hostname);
ret = write_and_get_response(&server_fd, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write STARTTLS to server:");
fflush(stdout);
gethostname(hostname, 32);
len = sprintf((char *) buf, "STARTTLS\r\n");
ret = write_and_get_response(&server_fd, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
if (do_handshake(&ssl) != 0) {
goto exit;
}
}
#if defined(MBEDTLS_BASE64_C)
if (opt.authentication) {
mbedtls_printf(" > Write AUTH LOGIN to server:");
fflush(stdout);
len = sprintf((char *) buf, "AUTH LOGIN\r\n");
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 399) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write username to server: %s", opt.user_name);
fflush(stdout);
ret = mbedtls_base64_encode(base, sizeof(base), &n, (const unsigned char *) opt.user_name,
strlen(opt.user_name));
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_base64_encode returned %d\n\n", ret);
goto exit;
}
len = sprintf((char *) buf, "%s\r\n", base);
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 300 || ret > 399) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write password to server: %s", opt.user_pwd);
fflush(stdout);
ret = mbedtls_base64_encode(base, sizeof(base), &n, (const unsigned char *) opt.user_pwd,
strlen(opt.user_pwd));
if (ret != 0) {
mbedtls_printf(" failed\n ! mbedtls_base64_encode returned %d\n\n", ret);
goto exit;
}
len = sprintf((char *) buf, "%s\r\n", base);
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 399) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
}
#endif
mbedtls_printf(" > Write MAIL FROM to server:");
fflush(stdout);
len = sprintf((char *) buf, "MAIL FROM:<%s>\r\n", opt.mail_from);
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write RCPT TO to server:");
fflush(stdout);
len = sprintf((char *) buf, "RCPT TO:<%s>\r\n", opt.mail_to);
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write DATA to server:");
fflush(stdout);
len = sprintf((char *) buf, "DATA\r\n");
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 300 || ret > 399) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_printf(" > Write content to server:");
fflush(stdout);
len = sprintf((char *) buf, "From: %s\r\nSubject: mbed TLS Test mail\r\n\r\n"
"This is a simple test mail from the "
"mbed TLS mail client example.\r\n"
"\r\n"
"Enjoy!", opt.mail_from);
ret = write_ssl_data(&ssl, buf, len);
len = sprintf((char *) buf, "\r\n.\r\n");
ret = write_ssl_and_get_response(&ssl, buf, len);
if (ret < 200 || ret > 299) {
mbedtls_printf(" failed\n ! server responded with %d\n\n", ret);
goto exit;
}
mbedtls_printf(" ok\n");
mbedtls_ssl_close_notify(&ssl);
exit_code = MBEDTLS_EXIT_SUCCESS;
exit:
mbedtls_net_free(&server_fd);
mbedtls_x509_crt_free(&clicert);
mbedtls_x509_crt_free(&cacert);
mbedtls_pk_free(&pkey);
mbedtls_ssl_free(&ssl);
mbedtls_ssl_config_free(&conf);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&entropy);
mbedtls_exit(exit_code);
}
#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_SSL_TLS_C &&
MBEDTLS_SSL_CLI_C && MBEDTLS_NET_C && MBEDTLS_RSA_C **
MBEDTLS_CTR_DRBG_C */