/
oncp.c
1765 lines (1558 loc) · 48.3 KB
/
oncp.c
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/*
* OpenConnect (SSL + DTLS) VPN client
*
* Copyright © 2008-2015 Intel Corporation.
*
* Author: David Woodhouse <dwmw2@infradead.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* version 2.1, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
/*
* Grateful thanks to Tiebing Zhang, who did much of the hard work
* of analysing and decoding the protocol.
*/
#include <config.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <stdarg.h>
#include <sys/types.h>
#ifndef _WIN32
#include <sys/wait.h>
#endif
#include <libxml/HTMLparser.h>
#include <libxml/HTMLtree.h>
#include "openconnect-internal.h"
/* XX: This is actually a lot of duplication with the CSTP version. */
void oncp_common_headers(struct openconnect_info *vpninfo, struct oc_text_buf *buf)
{
http_common_headers(vpninfo, buf);
buf_append(buf, "Connection: close\r\n");
// buf_append(buf, "Content-Length: 256\r\n");
buf_append(buf, "NCP-Version: 3\r\n");
// buf_append(buf, "Accept-Encoding: gzip\r\n");
}
static xmlNodePtr htmlnode_next(xmlNodePtr top, xmlNodePtr node)
{
if (node->children)
return node->children;
while (!node->next) {
node = node->parent;
if (!node || node == top)
return NULL;
}
return node->next;
}
static int oncp_can_gen_tokencode(struct openconnect_info *vpninfo,
struct oc_auth_form *form,
struct oc_form_opt *opt)
{
if (vpninfo->token_mode == OC_TOKEN_MODE_NONE ||
vpninfo->token_bypassed)
return -EINVAL;
if (strcmp(form->auth_id, "frmDefender") &&
strcmp(form->auth_id, "frmNextToken"))
return -EINVAL;
return can_gen_tokencode(vpninfo, form, opt);
}
static int parse_input_node(struct openconnect_info *vpninfo, struct oc_auth_form *form,
xmlNodePtr node, const char *submit_button)
{
const char *type = (const char *)xmlGetProp(node, (unsigned char *)"type");
struct oc_form_opt **p = &form->opts;
struct oc_form_opt *opt;
if (!type)
return -EINVAL;
opt = calloc(1, sizeof(*opt));
if (!opt)
return -ENOMEM;
if (!strcasecmp(type, "hidden")) {
opt->type = OC_FORM_OPT_HIDDEN;
xmlnode_get_prop(node, "name", &opt->name);
xmlnode_get_prop(node, "value", &opt->_value);
/* XXX: Handle tz_offset / tz */
} else if (!strcasecmp(type, "password")) {
opt->type = OC_FORM_OPT_PASSWORD;
xmlnode_get_prop(node, "name", &opt->name);
asprintf(&opt->label, "%s:", opt->name);
if (!oncp_can_gen_tokencode(vpninfo, form, opt))
opt->type = OC_FORM_OPT_TOKEN;
} else if (!strcasecmp(type, "text")) {
opt->type = OC_FORM_OPT_TEXT;
xmlnode_get_prop(node, "name", &opt->name);
asprintf(&opt->label, "%s:", opt->name);
} else if (!strcasecmp(type, "submit")) {
xmlnode_get_prop(node, "name", &opt->name);
if (!opt->name || strcmp(opt->name, submit_button)) {
vpn_progress(vpninfo, PRG_DEBUG,
_("Ignoring unknown form submit item '%s'\n"),
opt->name);
free_opt(opt);
return -EINVAL;
}
xmlnode_get_prop(node, "value", &opt->_value);
opt->type = OC_FORM_OPT_HIDDEN;
} else {
vpn_progress(vpninfo, PRG_DEBUG,
_("Ignoring unknown form input type '%s'\n"),
type);
free_opt(opt);
return -EINVAL;
}
/* Append to the existing list */
while (*p)
p = &(*p)->next;
*p = opt;
return 0;
}
static int parse_select_node(struct openconnect_info *vpninfo, struct oc_auth_form *form,
xmlNodePtr node)
{
xmlNodePtr child;
struct oc_form_opt_select *opt;
struct oc_choice *choice;
opt = calloc(1, sizeof(*opt));
if (!opt)
return -ENOMEM;
xmlnode_get_prop(node, "name", &opt->form.name);
opt->form.label = strdup(opt->form.name);
opt->form.type = OC_FORM_OPT_SELECT;
if (!strcmp(opt->form.name, "realm"))
form->authgroup_opt = opt;
for (child = node->children; child; child = child->next) {
if (!child->name || strcasecmp((const char *)child->name, "option"))
continue;
choice = calloc(1, sizeof(*choice));
if (!choice) {
free_opt((void *)choice);
return -ENOMEM;
}
xmlnode_get_prop(node, "name", &choice->name);
choice->label = (char *)xmlNodeGetContent(child);
choice->name = strdup(choice->label);
realloc_inplace(opt->choices, sizeof(opt->choices[0]) * (opt->nr_choices+1));
if (!opt->choices) {
opt->nr_choices = 0;
free_opt((void *)opt);
return -ENOMEM;
}
opt->choices[opt->nr_choices++] = choice;
}
/* Prepend to the existing list */
opt->form.next = form->opts;
form->opts = &opt->form;
return 0;
}
static struct oc_auth_form *parse_form_node(struct openconnect_info *vpninfo,
xmlNodePtr node, const char *submit_button)
{
struct oc_auth_form *form = calloc(1, sizeof(*form));
xmlNodePtr child;
if (!form)
return NULL;
xmlnode_get_prop(node, "method", &form->method);
xmlnode_get_prop(node, "action", &form->action);
if (!form->method || strcasecmp(form->method, "POST") ||
!form->action || !form->action[0]) {
vpn_progress(vpninfo, PRG_ERR,
_("Cannot handle form method='%s', action='%s'\n"),
form->method, form->action);
free(form);
return NULL;
}
xmlnode_get_prop(node, "name", &form->auth_id);
form->banner = strdup(form->auth_id);
for (child = htmlnode_next(node, node); child && child != node; child = htmlnode_next(node, child)) {
if (!child->name)
continue;
if (!strcasecmp((char *)child->name, "input"))
parse_input_node(vpninfo, form, child, submit_button);
else if (!strcasecmp((char *)child->name, "select")) {
parse_select_node(vpninfo, form, child);
/* Skip its children */
while (child->children)
child = child->last;
}
}
return form;
}
static int oncp_https_submit(struct openconnect_info *vpninfo,
struct oc_text_buf *req_buf, xmlDocPtr *doc)
{
int ret;
char *form_buf = NULL;
struct oc_text_buf *url;
if (req_buf && req_buf->pos)
ret =do_https_request(vpninfo, "POST",
"application/x-www-form-urlencoded",
req_buf, &form_buf, 2);
else
ret = do_https_request(vpninfo, "GET", NULL, NULL,
&form_buf, 2);
if (ret < 0)
return ret;
url = buf_alloc();
buf_append(url, "https://%s", vpninfo->hostname);
if (vpninfo->port != 443)
buf_append(url, ":%d", vpninfo->port);
buf_append(url, "/");
if (vpninfo->urlpath)
buf_append(url, "%s", vpninfo->urlpath);
if (buf_error(url)) {
free(form_buf);
return buf_free(url);
}
*doc = htmlReadMemory(form_buf, ret, url->data, NULL,
HTML_PARSE_RECOVER|HTML_PARSE_NOERROR|HTML_PARSE_NOWARNING|HTML_PARSE_NONET);
buf_free(url);
free(form_buf);
if (!*doc) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to parse HTML document\n"));
return -EINVAL;
}
return 0;
}
static xmlNodePtr find_form_node(xmlDocPtr doc)
{
xmlNodePtr root, node;
for (root = node = xmlDocGetRootElement(doc); node; node = htmlnode_next(root, node)) {
if (node->name && !strcasecmp((char *)node->name, "form"))
return node;
}
return NULL;
}
static int check_cookie_success(struct openconnect_info *vpninfo)
{
const char *dslast = NULL, *dsfirst = NULL, *dsurl = NULL, *dsid = NULL;
struct oc_vpn_option *cookie;
struct oc_text_buf *buf;
for (cookie = vpninfo->cookies; cookie; cookie = cookie->next) {
if (!strcmp(cookie->option, "DSFirstAccess"))
dsfirst = cookie->value;
else if (!strcmp(cookie->option, "DSLastAccess"))
dslast = cookie->value;
else if (!strcmp(cookie->option, "DSID"))
dsid = cookie->value;
else if (!strcmp(cookie->option, "DSSignInUrl"))
dsurl = cookie->value;
}
if (!dsid)
return -ENOENT;
buf = buf_alloc();
if (vpninfo->tncc_fd != -1) {
buf_append(buf, "setcookie\n");
buf_append(buf, "Cookie=%s\n", dsid);
if (buf_error(buf))
return buf_free(buf);
send(vpninfo->tncc_fd, buf->data, buf->pos, 0);
buf_truncate(buf);
}
/* XXX: Do these need escaping? Could they theoreetically have semicolons in? */
buf_append(buf, "DSID=%s", dsid);
if (dsfirst)
buf_append(buf, "; DSFirst=%s", dsfirst);
if (dslast)
buf_append(buf, "; DSLast=%s", dslast);
if (dsurl)
buf_append(buf, "; DSSignInUrl=%s", dsurl);
if (buf_error(buf))
return buf_free(buf);
free(vpninfo->cookie);
vpninfo->cookie = buf->data;
buf->data = NULL;
buf_free(buf);
return 0;
}
#ifdef _WIN32
static int tncc_preauth(struct openconnect_info *vpninfo)
{
vpn_progress(vpninfo, PRG_ERR,
_("TNCC support not implemented yet on Windows\n"));
return -EOPNOTSUPP;
}
#else
static int tncc_preauth(struct openconnect_info *vpninfo)
{
int sockfd[2];
pid_t pid;
struct oc_text_buf *buf;
struct oc_vpn_option *cookie;
const char *dspreauth = NULL, *dssignin = "null";
char recvbuf[1024], *p;
int len;
for (cookie = vpninfo->cookies; cookie; cookie = cookie->next) {
if (!strcmp(cookie->option, "DSPREAUTH"))
dspreauth = cookie->value;
else if (!strcmp(cookie->option, "DSSIGNIN"))
dssignin = cookie->value;
}
if (!dspreauth) {
vpn_progress(vpninfo, PRG_ERR,
_("No DSPREAUTH cookie; not attempting TNCC\n"));
return -EINVAL;
}
buf = buf_alloc();
buf_append(buf, "start\n");
buf_append(buf, "IC=%s\n", vpninfo->hostname);
buf_append(buf, "Cookie=%s\n", dspreauth);
buf_append(buf, "DSSIGNIN=%s\n", dssignin);
if (buf_error(buf)) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to allocate memory for communication with TNCC\n"));
return buf_free(buf);
}
#ifdef SOCK_CLOEXEC
if (socketpair(AF_UNIX, SOCK_SEQPACKET | SOCK_CLOEXEC, 0, sockfd))
#endif
{
if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sockfd))
return -errno;
set_fd_cloexec(sockfd[0]);
set_fd_cloexec(sockfd[1]);
}
pid = fork();
if (pid == -1) {
buf_free(buf);
return -errno;
}
if (!pid) {
int i;
/* Fork again to detach grandchild */
if (fork())
exit(1);
close(sockfd[1]);
/* The duplicated fd does not have O_CLOEXEC */
dup2(sockfd[0], 0);
/* We really don't want anything going to stdout */
dup2(1, 2);
for (i = 3; i < 1024 ; i++)
close(i);
execl(vpninfo->csd_wrapper, vpninfo->csd_wrapper, vpninfo->hostname, NULL);
fprintf(stderr, _("Failed to exec TNCC script %s: %s\n"),
vpninfo->csd_wrapper, strerror(errno));
exit(1);
}
waitpid(pid, NULL, 0);
close(sockfd[0]);
if (send(sockfd[1], buf->data, buf->pos, 0) != buf->pos) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to send start command to TNCC\n"));
buf_free(buf);
close(sockfd[1]);
return -EIO;
}
buf_free(buf);
vpn_progress(vpninfo, PRG_DEBUG,
_("Sent start; waiting for response from TNCC\n"));
len = recv(sockfd[1], recvbuf, sizeof(recvbuf) - 1, 0);
if (len < 0) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to read response from TNCC\n"));
close(sockfd[1]);
return -EIO;
}
recvbuf[len] = 0;
p = strchr(recvbuf, '\n');
if (!p) {
invalid_response:
vpn_progress(vpninfo, PRG_ERR,
_("Received invalid response from TNCC\n"));
print_response:
vpn_progress(vpninfo, PRG_TRACE, _("TNCC response: -->\n%s\n<--\n"),
recvbuf);
close(sockfd[1]);
return -EINVAL;
}
*p = 0;
if (strcmp(recvbuf, "200")) {
vpn_progress(vpninfo, PRG_ERR,
_("Received unsuccessful %s response from TNCC\n"),
recvbuf);
goto print_response;
}
p = strchr(p + 1, '\n');
if (!p)
goto invalid_response;
dspreauth = p + 1;
p = strchr(p + 1, '\n');
if (!p)
goto invalid_response;
*p = 0;
vpn_progress(vpninfo, PRG_DEBUG,
_("Got new DSPREAUTH cookie from TNCC: %s\n"),
dspreauth);
http_add_cookie(vpninfo, "DSPREAUTH", dspreauth, 1);
vpninfo->tncc_fd = sockfd[1];
return 0;
}
#endif
int oncp_obtain_cookie(struct openconnect_info *vpninfo)
{
int ret;
struct oc_text_buf *resp_buf = NULL;
xmlDocPtr doc = NULL;
xmlNodePtr node;
struct oc_auth_form *form = NULL;
char *form_id = NULL;
int try_tncc = !!vpninfo->csd_wrapper;
resp_buf = buf_alloc();
if (buf_error(resp_buf))
return -ENOMEM;
while (1) {
ret = oncp_https_submit(vpninfo, resp_buf, &doc);
if (ret || !check_cookie_success(vpninfo))
break;
buf_truncate(resp_buf);
node = find_form_node(doc);
if (!node) {
if (try_tncc) {
try_tncc = 0;
ret = tncc_preauth(vpninfo);
if (ret)
return ret;
goto tncc_done;
}
vpn_progress(vpninfo, PRG_ERR,
_("Failed to find or parse web form in login page\n"));
ret = -EINVAL;
break;
}
form_id = (char *)xmlGetProp(node, (unsigned char *)"name");
if (!form_id) {
vpn_progress(vpninfo, PRG_ERR,
_("Encountered form with no ID\n"));
goto dump_form;
} else if (!strcmp(form_id, "frmLogin")) {
form = parse_form_node(vpninfo, node, "btnSubmit");
if (!form) {
ret = -EINVAL;
break;
}
} else if (!strcmp(form_id, "frmDefender") ||
!strcmp(form_id, "frmNextToken")) {
form = parse_form_node(vpninfo, node, "btnAction");
if (!form) {
ret = -EINVAL;
break;
}
} else if (!strcmp(form_id, "frmConfirmation")) {
form = parse_form_node(vpninfo, node, "btnContinue");
if (!form) {
ret = -EINVAL;
break;
}
/* XXX: Actually ask the user? */
goto form_done;
} else {
vpn_progress(vpninfo, PRG_ERR,
_("Unknown form ID '%s'\n"),
form_id);
dump_form:
fprintf(stderr, _("Dumping unknown HTML form:\n"));
htmlNodeDumpFileFormat(stderr, node->doc, node, NULL, 1);
ret = -EINVAL;
break;
}
do {
ret = process_auth_form(vpninfo, form);
} while (ret == OC_FORM_RESULT_NEWGROUP);
if (ret)
goto out;
ret = do_gen_tokencode(vpninfo, form);
if (ret) {
vpn_progress(vpninfo, PRG_ERR, _("Failed to generate OTP tokencode; disabling token\n"));
vpninfo->token_bypassed = 1;
goto out;
}
form_done:
append_form_opts(vpninfo, form, resp_buf);
ret = buf_error(resp_buf);
if (ret)
break;
vpninfo->redirect_url = form->action;
form->action = NULL;
free_auth_form(form);
form = NULL;
handle_redirect(vpninfo);
tncc_done:
xmlFreeDoc(doc);
doc = NULL;
}
out:
if (doc)
xmlFreeDoc(doc);
free(form_id);
if (form)
free_auth_form(form);
buf_free(resp_buf);
return ret;
}
static int parse_cookie(struct openconnect_info *vpninfo)
{
char *p = vpninfo->cookie;
/* We currenly expect the "cookie" to be contain multiple cookies:
* DSSignInUrl=/; DSID=xxx; DSFirstAccess=xxx; DSLastAccess=xxx
* Process those into vpninfo->cookies unless we already had them
* (in which case they'll may be newer. */
while (p && *p) {
char *semicolon = strchr(p, ';');
char *equals;
if (semicolon)
*semicolon = 0;
equals = strchr(p, '=');
if (!equals) {
vpn_progress(vpninfo, PRG_ERR, _("Invalid cookie '%s'\n"), p);
return -EINVAL;
}
*equals = 0;
http_add_cookie(vpninfo, p, equals+1, 0);
*equals = '=';
p = semicolon;
if (p) {
*p = ';';
p++;
while (*p && isspace((int)(unsigned char)*p))
p++;
}
}
return 0;
}
static void buf_append_be16(struct oc_text_buf *buf, uint16_t val)
{
unsigned char b[2];
store_be16(b, val);
buf_append_bytes(buf, b, 2);
}
static void buf_append_le16(struct oc_text_buf *buf, uint16_t val)
{
unsigned char b[2];
store_le16(b, val);
buf_append_bytes(buf, b, 2);
}
static void buf_append_tlv(struct oc_text_buf *buf, uint16_t val, uint32_t len, void *data)
{
unsigned char b[6];
store_be16(b, val);
store_be32(b + 2, len);
buf_append_bytes(buf, b, 6);
if (len)
buf_append_bytes(buf, data, len);
}
static void buf_append_tlv_be32(struct oc_text_buf *buf, uint16_t val, uint32_t data)
{
unsigned char d[4];
store_be32(d, data);
buf_append_tlv(buf, val, 4, d);
}
static void buf_hexdump(struct openconnect_info *vpninfo, unsigned char *d, int len)
{
char linebuf[80];
int i;
for (i = 0; i < len; i++) {
if (i % 16 == 0) {
if (i)
vpn_progress(vpninfo, PRG_DEBUG, "%s\n", linebuf);
sprintf(linebuf, "%04x:", i);
}
sprintf(linebuf + strlen(linebuf), " %02x", d[i]);
}
vpn_progress(vpninfo, PRG_DEBUG, "%s\n", linebuf);
}
static const char authpkt_head[] = { 0x00, 0x04, 0x00, 0x00, 0x00 };
static const char authpkt_tail[] = { 0xbb, 0x01, 0x00, 0x00, 0x00, 0x00 };
#define GRP_ATTR(g, a) (((g) << 16) | (a))
/* We behave like CSTP — create a linked list in vpninfo->cstp_options
* with the strings containing the information we got from the server,
* and oc_ip_info contains const copies of those pointers. */
static const char *add_option(struct openconnect_info *vpninfo, const char *opt,
const char *val, int val_len)
{
struct oc_vpn_option *new = malloc(sizeof(*new));
if (!new)
return NULL;
new->option = strdup(opt);
if (!new->option) {
free(new);
return NULL;
}
if (val_len >= 0)
new->value = strndup(val, val_len);
else
new->value = strdup(val);
if (!new->value) {
free(new->option);
free(new);
return NULL;
}
new->next = vpninfo->cstp_options;
vpninfo->cstp_options = new;
return new->value;
}
static int process_attr(struct openconnect_info *vpninfo, int group, int attr,
unsigned char *data, int attrlen)
{
char buf[80];
int i;
switch(GRP_ATTR(group, attr)) {
case GRP_ATTR(6, 2):
if (attrlen != 4) {
badlen:
vpn_progress(vpninfo, PRG_ERR,
_("Unexpected length %d for TLV %d/%d\n"),
attrlen, group, attr);
return -EINVAL;
goto badlen;
}
vpninfo->ip_info.mtu = load_be32(data);
vpn_progress(vpninfo, PRG_DEBUG,
_("Received MTU %d from server\n"),
vpninfo->ip_info.mtu);
break;
case GRP_ATTR(2, 1):
if (attrlen != 4)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d", data[0], data[1], data[2], data[3]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received DNS server %s\n"), buf);
for (i = 0; i < 3; i++) {
if (!vpninfo->ip_info.dns[i]) {
vpninfo->ip_info.dns[i] = add_option(vpninfo, "DNS", buf, -1);
break;
}
}
break;
case GRP_ATTR(2, 2):
vpn_progress(vpninfo, PRG_DEBUG, _("Received DNS search domain %.*s\n"),
attrlen, (char *)data);
vpninfo->ip_info.domain = add_option(vpninfo, "search", (char *)data, attrlen);
break;
case GRP_ATTR(1, 1):
if (attrlen != 4)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d", data[0], data[1], data[2], data[3]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received internal IP address %s\n"), buf);
vpninfo->ip_info.addr = add_option(vpninfo, "ipaddr", buf, -1);
break;
case GRP_ATTR(1, 2):
if (attrlen != 4)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d", data[0], data[1], data[2], data[3]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received netmask %s\n"), buf);
vpninfo->ip_info.netmask = add_option(vpninfo, "netmask", buf, -1);
break;
case GRP_ATTR(1, 3):
if (attrlen != 4)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d", data[0], data[1], data[2], data[3]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received internal gateway address %s\n"), buf);
/* Hm, what are we supposed to do with this? It's a tunnel;
having a gateway is meaningless. */
add_option(vpninfo, "ipaddr", buf, -1);
break;
case GRP_ATTR(3, 3): {
struct oc_split_include *inc;
if (attrlen != 8)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d/%d.%d.%d.%d",
data[0], data[1], data[2], data[3],
data[4], data[5], data[6], data[7]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received split include route %s\n"), buf);
if (!data[4] && !data[5] && !data[6] && !data[7])
break;
inc = malloc(sizeof(*inc));
if (inc) {
inc->route = add_option(vpninfo, "split-include", buf, -1);
if (inc->route) {
inc->next = vpninfo->ip_info.split_includes;
vpninfo->ip_info.split_includes = inc;
} else
free(inc);
}
break;
}
case GRP_ATTR(4, 1):
if (attrlen != 4)
goto badlen;
snprintf(buf, sizeof(buf), "%d.%d.%d.%d", data[0], data[1], data[2], data[3]);
vpn_progress(vpninfo, PRG_DEBUG, _("Received WINS server %s\n"), buf);
for (i = 0; i < 3; i++) {
if (!vpninfo->ip_info.nbns[i]) {
vpninfo->ip_info.nbns[i] = add_option(vpninfo, "WINS", buf, -1);
break;
}
}
break;
case GRP_ATTR(8, 1): {
const char *enctype;
if (attrlen != 1)
goto badlen;
if (data[0] == 0x02)
enctype = "AES-128";
else if (data[0] == 0x05)
enctype = "AES-256";
else
enctype = "unknown";
vpn_progress(vpninfo, PRG_DEBUG, _("ESP encryption: 0x%02x (%s)\n"),
data[0], enctype);
vpninfo->esp_enc = data[0];
break;
}
case GRP_ATTR(8, 2): {
const char *mactype;
if (attrlen != 1)
goto badlen;
if (data[0] == 0x01)
mactype = "MD5";
else if (data[0] == 0x02)
mactype = "SHA1";
else
mactype = "unknown";
vpn_progress(vpninfo, PRG_DEBUG, _("ESP HMAC: 0x%02x (%s)\n"),
data[0], mactype);
vpninfo->esp_hmac = data[0];
break;
}
case GRP_ATTR(8, 3):
if (attrlen != 1)
goto badlen;
vpninfo->esp_compr = data[0];
vpn_progress(vpninfo, PRG_DEBUG, _("ESP compression: %d\n"), data[0]);
break;
case GRP_ATTR(8, 4):
if (attrlen != 2)
goto badlen;
i = load_be16(data);
udp_sockaddr(vpninfo, i);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP port: %d\n"), i);
break;
case GRP_ATTR(8, 5):
if (attrlen != 4)
goto badlen;
vpninfo->esp_lifetime_bytes = load_be32(data);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP key lifetime: %u bytes\n"),
vpninfo->esp_lifetime_bytes);
break;
case GRP_ATTR(8, 6):
if (attrlen != 4)
goto badlen;
vpninfo->esp_lifetime_seconds = load_be32(data);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP key lifetime: %u seconds\n"),
vpninfo->esp_lifetime_seconds);
break;
case GRP_ATTR(8, 9):
if (attrlen != 4)
goto badlen;
vpninfo->esp_ssl_fallback = load_be32(data);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP to SSL fallback: %u seconds\n"),
vpninfo->esp_ssl_fallback);
break;
case GRP_ATTR(8, 10):
if (attrlen != 4)
goto badlen;
vpninfo->esp_replay_protect = load_be32(data);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP replay protection: %d\n"),
load_be32(data));
break;
case GRP_ATTR(7, 1):
if (attrlen != 4)
goto badlen;
memcpy(&vpninfo->esp_out.spi, data, 4);
vpn_progress(vpninfo, PRG_DEBUG, _("ESP SPI (outbound): %x\n"),
load_be32(data));
break;
case GRP_ATTR(7, 2):
if (attrlen != 0x40)
goto badlen;
memcpy(vpninfo->esp_out.secrets, data, 0x40);
vpn_progress(vpninfo, PRG_DEBUG, _("%d bytes of ESP secrets\n"),
attrlen);
break;
default:
buf[0] = 0;
for (i=0; i < 16 && i < attrlen; i++)
sprintf(buf + strlen(buf), " %02x", data[i]);
if (attrlen > 16)
sprintf(buf + strlen(buf), "...");
vpn_progress(vpninfo, PRG_DEBUG,
_("Unknown TLV group %d attr %d len %d:%s\n"),
group, attr, attrlen, buf);
}
return 0;
}
static void put_len16(struct oc_text_buf *buf, int where)
{
int len = buf->pos - where;
store_be16(buf->data + where - 2, len);
}
static void put_len32(struct oc_text_buf *buf, int where)
{
int len = buf->pos - where;
store_be32(buf->data + where - 4, len);
}
/* We don't know what these are so just hope they never change */
static const unsigned char kmp_head[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
static const unsigned char kmp_tail[] = { 0x01, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00 };
static const unsigned char kmp_tail_out[] = { 0x01, 0x00, 0x00, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00 };
static const unsigned char data_hdr[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x01, 0x2c, 0x01, 0x00, 0x00, 0x00,
0x01, 0x00, 0x00, 0x00, 0x00, 0x00 };
static const unsigned char esp_kmp_hdr[] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x2e,
0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, /* KMP header */
0x00, 0x56, /* KMP length */
0x00, 0x07, 0x00, 0x00, 0x00, 0x50, /* TLV group 7 */
0x00, 0x01, 0x00, 0x00, 0x00, 0x04, /* Attr 1 (SPI) */
};
/* Followed by 4 bytes of SPI */
static const unsigned char esp_kmp_part2[] = {
0x00, 0x02, 0x00, 0x00, 0x00, 0x40, /* Attr 2 (secrets) */
};
/* And now 0x40 bytes of random secret for encryption and HMAC key */
static const struct pkt esp_enable_pkt = {
.next = NULL,
{ .oncp.hdr = {
0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x01, 0x2f, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x0d
} },
.data = {
0x00, 0x06, 0x00, 0x00, 0x00, 0x07, /* Group 6, len 7 */
0x00, 0x01, 0x00, 0x00, 0x00, 0x01, /* Attr 1, len 1 */
0x01
},
.len = 13
};
int queue_esp_control(struct openconnect_info *vpninfo, int enable)
{
struct pkt *new = malloc(sizeof(*new) + 13);
if (!new)
return -ENOMEM;
memcpy(new, &esp_enable_pkt, sizeof(*new) + 13);
new->data[12] = enable;
queue_packet(&vpninfo->oncp_control_queue, new);
return 0;
}
static int check_kmp_header(struct openconnect_info *vpninfo, unsigned char *bytes, int pktlen)
{
if (pktlen < 20 || memcmp(bytes, kmp_head, sizeof(kmp_head)) ||
memcmp(bytes + 8, kmp_tail, sizeof(kmp_tail))) {
vpn_progress(vpninfo, PRG_ERR,
_("Failed to parse KMP header\n"));
return -EINVAL;
}
return load_be16(bytes + 6);
}
static int parse_conf_pkt(struct openconnect_info *vpninfo, unsigned char *bytes, int pktlen, int kmp)
{
int kmplen, kmpend, grouplen, groupend, group, attr, attrlen;
int ofs = 0;
kmplen = load_be16(bytes + ofs + 18);
kmpend = ofs + kmplen;
if (kmpend > pktlen) {
eparse:
vpn_progress(vpninfo, PRG_ERR,
_("Failed to parse KMP message\n"));
return -EINVAL;
}