Add signatures to Dictionary, and fix unhex() API in Utils to be a little safer.

This commit is contained in:
Adam Ierymenko 2014-08-05 09:56:49 -07:00
parent 7adf0eac7e
commit e3c5ada3a7
5 changed files with 228 additions and 136 deletions

View file

@ -34,8 +34,15 @@
#include "Constants.hpp"
// Three fields are added/updated by sign()
#define ZT_DICTIONARY_SIGNATURE "~!ed25519"
#define ZT_DICTIONARY_SIGNATURE_IDENTITY "~!sigid"
#define ZT_DICTIONARY_SIGNATURE_TIMESTAMP "~!sigts"
namespace ZeroTier {
class Identity;
/**
* Simple key/value dictionary with string serialization
*
@ -43,29 +50,29 @@ namespace ZeroTier {
* It does not support comments or other syntactic complexities. It is
* human-readable if the keys and values in the dictionary are also
* human-readable. Otherwise it might contain unprintable characters.
*
* Keys beginning with "~!" are reserved for signatures and are ignored
* during the signature process.
*
* Note: the signature code depends on std::map<> being sorted, but no
* other code does. So if the underlying data structure is ever swapped
* out for an unsorted one, the signature code will have to be updated
* to sort before composing the string to sign.
*/
class Dictionary : public std::map<std::string,std::string>
{
public:
Dictionary()
{
}
Dictionary() {}
/**
* @param s String-serialized dictionary
*/
Dictionary(const char *s)
{
fromString(s);
}
Dictionary(const char *s) { fromString(s); }
/**
* @param s String-serialized dictionary
*/
Dictionary(const std::string &s)
{
fromString(s.c_str());
}
Dictionary(const std::string &s) { fromString(s.c_str()); }
/**
* Get a key, throwing an exception if it is not present
@ -102,10 +109,7 @@ public:
* @param key Key to check
* @return True if dictionary contains key
*/
inline bool contains(const std::string &key) const
{
return (find(key) != end());
}
inline bool contains(const std::string &key) const { return (find(key) != end()); }
/**
* @return String-serialized dictionary
@ -113,14 +117,12 @@ public:
inline std::string toString() const
{
std::string s;
for(const_iterator kv(begin());kv!=end();++kv) {
_appendEsc(kv->first.data(),(unsigned int)kv->first.length(),s);
s.push_back('=');
_appendEsc(kv->second.data(),(unsigned int)kv->second.length(),s);
s.append(ZT_EOL_S);
}
return s;
}
@ -129,78 +131,43 @@ public:
*
* @param s String-serialized dictionary
*/
inline void fromString(const char *s)
void fromString(const char *s);
inline void fromString(const std::string &s) { fromString(s.c_str()); }
/**
* @return True if this dictionary is cryptographically signed
*/
inline bool hasSignature() const { return (find(ZT_DICTIONARY_SIGNATURE) != end()); }
/**
* Remove any signature from this dictionary
*/
inline void removeSignature()
{
clear();
bool escapeState = false;
std::string keyBuf;
std::string *element = &keyBuf;
while (*s) {
if (escapeState) {
escapeState = false;
switch(*s) {
case '0':
element->push_back((char)0);
break;
case 'r':
element->push_back('\r');
break;
case 'n':
element->push_back('\n');
break;
default:
element->push_back(*s);
break;
}
} else {
if (*s == '\\') {
escapeState = true;
} else if (*s == '=') {
if (element == &keyBuf)
element = &((*this)[keyBuf]);
} else if ((*s == '\r')||(*s == '\n')) {
if ((element == &keyBuf)&&(keyBuf.length() > 0))
(*this)[keyBuf];
keyBuf = "";
element = &keyBuf;
} else element->push_back(*s);
}
++s;
}
if ((element == &keyBuf)&&(keyBuf.length() > 0))
(*this)[keyBuf];
}
inline void fromString(const std::string &s)
{
fromString(s.c_str());
erase(ZT_DICTIONARY_SIGNATURE);
erase(ZT_DICTIONARY_SIGNATURE_IDENTITY);
erase(ZT_DICTIONARY_SIGNATURE_TIMESTAMP);
}
/**
* Add or update signature fields with a signature of all other keys and values
*
* @param with Identity to sign with (must have secret key)
* @return True on success
*/
bool sign(const Identity &id);
/**
* Verify signature against an identity
*
* @param id Identity to verify against
* @return True if signature verification OK
*/
bool verify(const Identity &id) const;
private:
static inline void _appendEsc(const char *data,unsigned int len,std::string &to)
{
for(unsigned int i=0;i<len;++i) {
switch(data[i]) {
case 0:
to.append("\\0");
break;
case '\r':
to.append("\\r");
break;
case '\n':
to.append("\\n");
break;
case '\\':
to.append("\\\\");
break;
case '=':
to.append("\\=");
break;
default:
to.push_back(data[i]);
break;
}
}
}
void _mkSigBuf(std::string &buf) const;
static void _appendEsc(const char *data,unsigned int len,std::string &to);
};
} // namespace ZeroTier