Andrew Boyson / web

Common stuff for all my devices' web server pages: css, login, log, ipv4, ipv6, firmware update, clock, reset info etc.

Dependents:   oldheating gps motorhome heating

Security

A password has to be set whenever there has been a software reset. Resets following faults or power on do not require a new password as the hash is restored from the RTC GPREG register.

The password is not saved on the device; instead a 32 bit hash of the password is saved. It would take 2^31 attempts to brute force the password: this could be done in under a month if an attempt were possible every millisecond. To prevent this a 200 ms delay is introduced in the reply to the login form, that gives a more reasonable 13 years to brute force the password.

Once the password is accepted a random session id is created. This is 36 bit to give six base 64 characters but without an extra delay. If an attempt could be made every ms then this would still take over a year to brute force.

The most likely attack would to use a dictionary with, say, 10 million entries against the password which would still take 20 days to do.

web-add.h

Committer:
andrewboyson
Date:
2019-05-01
Revision:
113:23507d14f927
Parent:
core/web-add.h@ 110:8ab752842d25
Child:
118:53430a2a2595

File content as of revision 113:23507d14f927:

#include <stdint.h>
#include <stdbool.h>

extern void WebAddNavItem      (int highlight, char* href, char* title);
extern void WebAddNav          (int page);
extern void WebAddHeader       (const char* title, const char* style, const char* script);
extern void WebAddH1           (const char* pageName);
extern void WebAddH2           (const char* text);
extern void WebAddEnd          (void);

extern void WebAddLabelledText        (char* label,                     char* text);
extern void WebAddLabelledPrefixSuffix(char* label,   char* prefix,     char* text,  char* suffix);
extern void WebAddLabelledMac         (char* label,                     char*   mac);
extern void WebAddLabelledIp4         (char* label,                     uint32_t ip);
extern void WebAddLabelledIp6         (char* label,                     char*    ip);
extern void WebAddLabelledOnOff       (char* label,                     bool  value);
extern void WebAddLabelledInt         (char* label,                     int   value);

extern void WebAddInputText           (char* label,   float inputwidth, char* value, char* action, char* name);
extern void WebAddInputInt            (char* label,   float inputwidth, int   value, char* action, char* name);
extern void WebAddInputButton         (char* label,                     char* value, char* action, char* name);

extern void WebAddAjaxLed             (char* label,                     char* id);
extern void WebAddAjaxLabelled        (char* label,                     char* id);
extern void WebAddAjaxLabelledSuffix  (char* label,                     char* id, char* suffix);
extern void WebAddAjaxInputToggle     (char* label,                     char* id, char* name);
extern void WebAddAjaxInput           (char* label,   float inputwidth, char* id, char* name);
extern void WebAddAjaxInputSuffix     (char* label,   float inputwidth, char* id, char* name, char* suffix);
extern void WebAddAjaxInputLabelId    (char* labelId, float inputwidth, char* id, char* name);