332 lines
13 KiB
C

// Copyright (c) 2023 Cesanta Software Limited
// All rights reserved
#include "net.h"
// Authenticated user.
// A user can be authenticated by:
// - a name:pass pair, passed in a header Authorization: Basic .....
// - an access_token, passed in a header Cookie: access_token=....
// When a user is shown a login screen, she enters a user:pass. If successful,
// a server responds with a http-only access_token cookie set.
struct user {
const char *name, *pass, *access_token;
};
// Event log entry
struct event {
int type, prio;
unsigned long timestamp;
const char *text;
};
// Connected Devices
struct device {
char *dev_name;
char *mac;
char *ip_addr;
int speed;
char *connected_to;
int lease_time_left;
char *last_seen;
};
static struct device s_devices[] = {{.dev_name = "espressif",
.mac = "02:11:22:33:44:55",
.ip_addr = "192.168.1.1/24",
.speed = 1000,
.connected_to = "Ethernet",
.lease_time_left = 1000,
.last_seen = "13h20m ago"},
{.dev_name = "windows11",
.mac = "01:22:11:44:33:55",
.ip_addr = "192.168.1.2/24",
.speed = 200,
.connected_to = "Wifi 2.4 GHz",
.lease_time_left = 4141,
.last_seen = "23s ago"},
{.dev_name = "iRobot-2",
.mac = "01:22:11:44:33:42",
.ip_addr = "192.168.1.3/24",
.speed = 600,
.connected_to = "Wifi 5GHz",
.lease_time_left = 1141,
.last_seen = "20m ago"}};
// DHCP configuration
struct dhcp {
bool enabled;
uint8_t address_begin;
uint8_t address_end;
unsigned long lease_time_sec;
};
static struct dhcp s_dhcp = {true, 10, 250, 86400};
// Mocked events
static struct event s_events[] = {
{.type = 0, .prio = 0, .text = "here goes event 1"},
{.type = 1, .prio = 2, .text = "event 2..."},
{.type = 2, .prio = 1, .text = "another event"},
{.type = 1, .prio = 1, .text = "something happened!"},
{.type = 2, .prio = 0, .text = "once more..."},
{.type = 2, .prio = 0, .text = "more again..."},
{.type = 1, .prio = 1, .text = "oops. it happened again"},
};
static const char *s_json_header =
"Content-Type: application/json\r\n"
"Cache-Control: no-cache\r\n";
static uint64_t s_boot_timestamp = 0; // Updated by SNTP
// Certificate generation procedure:
// openssl ecparam -name prime256v1 -genkey -noout -out key.pem
// openssl req -new -key key.pem -x509 -nodes -days 3650 -out cert.pem
static const char *s_tls_cert =
"-----BEGIN CERTIFICATE-----\n"
"MIIBCTCBsAIJAK9wbIDkHnAoMAoGCCqGSM49BAMCMA0xCzAJBgNVBAYTAklFMB4X\n"
"DTIzMDEyOTIxMjEzOFoXDTMzMDEyNjIxMjEzOFowDTELMAkGA1UEBhMCSUUwWTAT\n"
"BgcqhkjOPQIBBggqhkjOPQMBBwNCAARzSQS5OHd17lUeNI+6kp9WYu0cxuEIi/JT\n"
"jphbCmdJD1cUvhmzM9/phvJT9ka10Z9toZhgnBq0o0xfTQ4jC1vwMAoGCCqGSM49\n"
"BAMCA0gAMEUCIQCe0T2E0GOiVe9KwvIEPeX1J1J0T7TNacgR0Ya33HV9VgIgNvdn\n"
"aEWiBp1xshs4iz6WbpxrS1IHucrqkZuJLfNZGZI=\n"
"-----END CERTIFICATE-----\n";
static const char *s_tls_key =
"-----BEGIN EC PRIVATE KEY-----\n"
"MHcCAQEEICBz3HOkQLPBDtdknqC7k1PNsWj6HfhyNB5MenfjmqiooAoGCCqGSM49\n"
"AwEHoUQDQgAEc0kEuTh3de5VHjSPupKfVmLtHMbhCIvyU46YWwpnSQ9XFL4ZszPf\n"
"6YbyU/ZGtdGfbaGYYJwatKNMX00OIwtb8A==\n"
"-----END EC PRIVATE KEY-----\n";
static int event_next(int no, struct event *e) {
if (no < 0 || no >= (int) (sizeof(s_events) / sizeof(s_events[0]))) return 0;
*e = s_events[no];
return no + 1;
}
// SNTP connection event handler. When we get a response from an SNTP server,
// adjust s_boot_timestamp. We'll get a valid time from that point on
static void sfn(struct mg_connection *c, int ev, void *ev_data) {
uint64_t *expiration_time = (uint64_t *) c->data;
if (ev == MG_EV_OPEN) {
*expiration_time = mg_millis() + 3000; // Store expiration time in 3s
} else if (ev == MG_EV_SNTP_TIME) {
uint64_t t = *(uint64_t *) ev_data;
s_boot_timestamp = t - mg_millis();
c->is_closing = 1;
} else if (ev == MG_EV_POLL) {
if (mg_millis() > *expiration_time) c->is_closing = 1;
}
}
static void timer_sntp_fn(void *param) { // SNTP timer function. Sync up time
mg_sntp_connect(param, "udp://time.google.com:123", sfn, NULL);
}
// Parse HTTP requests, return authenticated user or NULL
static struct user *authenticate(struct mg_http_message *hm) {
// In production, make passwords strong and tokens randomly generated
// In this example, user list is kept in RAM. In production, it can
// be backed by file, database, or some other method.
static struct user users[] = {
{"admin", "admin", "admin_token"},
{"user1", "user1", "user1_token"},
{"user2", "user2", "user2_token"},
{NULL, NULL, NULL},
};
char user[64], pass[64];
struct user *u, *result = NULL;
mg_http_creds(hm, user, sizeof(user), pass, sizeof(pass));
MG_INFO(("user [%s] pass [%s]", user, pass));
if (user[0] != '\0' && pass[0] != '\0') {
// Both user and password is set, search by user/password
for (u = users; result == NULL && u->name != NULL; u++)
if (strcmp(user, u->name) == 0 && strcmp(pass, u->pass) == 0) result = u;
} else if (user[0] == '\0') {
// Only password is set, search by token
for (u = users; result == NULL && u->name != NULL; u++)
if (strcmp(pass, u->access_token) == 0) result = u;
}
return result;
}
static void handle_login(struct mg_connection *c, struct user *u) {
char cookie[256];
const char *cookie_name = c->is_tls ? "secure_access_token" : "access_token";
mg_snprintf(cookie, sizeof(cookie),
"Set-Cookie: %s=%s;Path=/;"
"%sHttpOnly;SameSite=Lax;Max-Age=%d\r\n", cookie_name,
u->access_token, c->is_tls ? "Secure; " : "", 3600 * 24);
mg_http_reply(c, 200, cookie, "{%m:%m}", MG_ESC("user"), MG_ESC(u->name));
}
static void handle_logout(struct mg_connection *c) {
char cookie[256];
const char *cookie_name = c->is_tls ? "secure_access_token" : "access_token";
mg_snprintf(cookie, sizeof(cookie),
"Set-Cookie: %s=; Path=/; "
"Expires=Thu, 01 Jan 1970 00:00:00 UTC; "
"%sHttpOnly; Max-Age=0; \r\n", cookie_name,
c->is_tls ? "Secure; " : "");
mg_http_reply(c, 200, cookie, "true\n");
}
static void handle_debug(struct mg_connection *c, struct mg_http_message *hm) {
int level = mg_json_get_long(hm->body, "$.level", MG_LL_DEBUG);
mg_log_set(level);
mg_http_reply(c, 200, "", "Debug level set to %d\n", level);
}
static size_t print_int_arr(void (*out)(char, void *), void *ptr, va_list *ap) {
size_t len = 0, num = va_arg(*ap, size_t); // Number of items in the array
int *arr = va_arg(*ap, int *); // Array ptr
for (size_t i = 0; i < num; i++) {
len += mg_xprintf(out, ptr, "%s%d", i == 0 ? "" : ",", arr[i]);
}
return len;
}
static void handle_stats_get(struct mg_connection *c) {
int us[] = {124, 123, 7, 7, 8, 8, 125, 125, 124, 125, 134, 145};
int ds[] = {430, 310, 56, 57, 68, 450, 470, 410, 420, 480, 490, 455};
mg_http_reply(
c, 200, s_json_header, "{%m:%d,%m:%lu,%m:%lu,%m:[%M],%m:[%M]}",
MG_ESC("connected_devices"), 17, //
MG_ESC("uploaded"), 2187, //
MG_ESC("downloaded"), 17934, //
MG_ESC("upload_speed"), print_int_arr, sizeof(us) / sizeof(us[0]), us, //
MG_ESC("download_speed"), print_int_arr, sizeof(ds) / sizeof(ds[0]), ds);
}
static size_t print_events(void (*out)(char, void *), void *ptr, va_list *ap) {
size_t len = 0;
struct event e;
int no = 0;
while ((no = event_next(no, &e)) != 0) {
len += mg_xprintf(out, ptr, "%s{%m:%lu,%m:%d,%m:%d,%m:%m}", //
len == 0 ? "" : ",", //
MG_ESC("time"), e.timestamp, //
MG_ESC("type"), e.type, //
MG_ESC("prio"), e.prio, //
MG_ESC("text"), MG_ESC(e.text));
}
(void) ap;
return len;
}
static void handle_events_get(struct mg_connection *c) {
mg_http_reply(c, 200, s_json_header, "[%M]", print_events);
}
static void handle_devices_get(struct mg_connection *c) {
char test_json[1024];
int nr_devs = sizeof(s_devices) / sizeof(struct device);
memset(test_json, 0, sizeof(test_json));
test_json[0] = '[';
for (int i = 0; i < nr_devs; i++) {
size_t current_length = strlen(test_json);
mg_snprintf(
test_json + current_length, sizeof(test_json) - current_length,
"{%m:\"%s\",%m:\"%s\", %m:\"%s\", %m:%d,%m:\"%s\",%m:%d,%m:\"%s\"}", //
MG_ESC("dev_name"), s_devices[i].dev_name, //
MG_ESC("mac"), s_devices[i].mac, //
MG_ESC("ip"), s_devices[i].ip_addr, //
MG_ESC("speed"), s_devices[i].speed, //
MG_ESC("connected_to"), s_devices[i].connected_to, //
MG_ESC("lease_time_left"), s_devices[i].lease_time_left, //
MG_ESC("last_seen"), s_devices[i].last_seen);
if (i < nr_devs - 1) {
strncat(test_json, ",", sizeof(test_json) - strlen(test_json) - 1);
}
}
strncat(test_json, "]", sizeof(test_json) - strlen(test_json) - 1);
mg_http_reply(c, 200, s_json_header, "%s", test_json);
}
static void handle_dhcp_set(struct mg_connection *c, struct mg_str body) {
struct dhcp dhcp;
memset(&dhcp, 0, sizeof(dhcp));
mg_json_get_bool(body, "$.enabled", &dhcp.enabled);
dhcp.address_begin = mg_json_get_long(body, "$.address_begin", 0);
dhcp.address_end = mg_json_get_long(body, "$.address_end", 0);
dhcp.lease_time_sec = mg_json_get_long(body, "$.lease_time_sec", 0);
s_dhcp = dhcp; // Save to the device flash, too
bool ok = true;
mg_http_reply(c, 200, s_json_header,
"{%m:%s,%m:%m}", //
MG_ESC("status"), ok ? "true" : "false", //
MG_ESC("message"), MG_ESC(ok ? "Success" : "Failed"));
}
static void handle_dhcp_get(struct mg_connection *c) {
mg_http_reply(c, 200, s_json_header, "{%m:%s,%m:%hhu,%m:%hhu,%m:%lu}", //
MG_ESC("enabled"), s_dhcp.enabled ? "true" : "false", //
MG_ESC("address_begin"), s_dhcp.address_begin, //
MG_ESC("address_end"), s_dhcp.address_end, //
MG_ESC("lease_time_sec"), s_dhcp.lease_time_sec);
}
// HTTP request handler function
static void fn(struct mg_connection *c, int ev, void *ev_data) {
if (ev == MG_EV_ACCEPT) {
if (c->fn_data != NULL) { // TLS
struct mg_tls_opts opts = {0};
opts.cert = mg_str(s_tls_cert);
opts.key = mg_str(s_tls_key);
mg_tls_init(c, &opts);
}
} else if (ev == MG_EV_HTTP_MSG) {
struct mg_http_message *hm = (struct mg_http_message *) ev_data;
struct user *u = authenticate(hm);
if (mg_match(hm->uri, mg_str("/api/#"), NULL) && u == NULL) {
mg_http_reply(c, 403, "", "Not Authorised\n");
} else if (mg_match(hm->uri, mg_str("/api/login"), NULL)) {
handle_login(c, u);
} else if (mg_match(hm->uri, mg_str("/api/logout"), NULL)) {
handle_logout(c);
} else if (mg_match(hm->uri, mg_str("/api/debug"), NULL)) {
handle_debug(c, hm);
} else if (mg_match(hm->uri, mg_str("/api/stats/get"), NULL)) {
handle_stats_get(c);
} else if (mg_match(hm->uri, mg_str("/api/events/get"), NULL)) {
handle_events_get(c);
} else if (mg_match(hm->uri, mg_str("/api/devices/get"), NULL)) {
handle_devices_get(c);
} else if (mg_match(hm->uri, mg_str("/api/dhcp/get"), NULL)) {
handle_dhcp_get(c);
} else if (mg_match(hm->uri, mg_str("/api/dhcp/set"), NULL)) {
handle_dhcp_set(c, hm->body);
} else {
struct mg_http_serve_opts opts;
memset(&opts, 0, sizeof(opts));
#if MG_ENABLE_PACKED_FS
opts.root_dir = "/web_root";
opts.fs = &mg_fs_packed;
#else
opts.root_dir = "web_root";
#endif
mg_http_serve_dir(c, ev_data, &opts);
}
MG_DEBUG(("%lu %.*s %.*s -> %.*s", c->id, (int) hm->method.len,
hm->method.buf, (int) hm->uri.len, hm->uri.buf, (int) 3,
&c->send.buf[9]));
}
}
void web_init(struct mg_mgr *mgr) {
mg_http_listen(mgr, HTTP_URL, fn, NULL);
mg_http_listen(mgr, HTTPS_URL, fn, (void *) 1);
// mg_timer_add(c->mgr, 1000, MG_TIMER_REPEAT, timer_mqtt_fn, c->mgr);
mg_timer_add(mgr, 3600 * 1000, MG_TIMER_RUN_NOW | MG_TIMER_REPEAT,
timer_sntp_fn, mgr);
}