Andrew Boyson / crypto

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tls/tls-connection.c@8:5e66a6b4b38c, 2019-09-07 (annotated)

Committer:
andrewboyson
Date:
Sat Sep 07 18:56:01 2019 +0000
Revision:
8:5e66a6b4b38c
Parent:
6:819c17738dc2
Child:
10:e269fd7b9500
Got TLS working as far as being able to verify finished message itself and to verify the MAC on the finished and the subsequent alert message.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 5:ee5489ee1117 1 #include <stdlib.h>
andrewboyson 5:ee5489ee1117 2
andrewboyson 5:ee5489ee1117 3 #include "tls-connection.h"
andrewboyson 5:ee5489ee1117 4 #include "mstimer.h"
andrewboyson 5:ee5489ee1117 5
andrewboyson 5:ee5489ee1117 6 #define MAX_CONNECTIONS 4
andrewboyson 5:ee5489ee1117 7
andrewboyson 5:ee5489ee1117 8 static struct TlsConnection connections[MAX_CONNECTIONS];
andrewboyson 5:ee5489ee1117 9
andrewboyson 8:5e66a6b4b38c 10 struct TlsConnection* TlsConnectionGetNext()
andrewboyson 8:5e66a6b4b38c 11 {
andrewboyson 8:5e66a6b4b38c 12 static struct TlsConnection* p = connections + MAX_CONNECTIONS - 1; //Initialise to last element
andrewboyson 8:5e66a6b4b38c 13 p++;
andrewboyson 8:5e66a6b4b38c 14 if (p >= connections + MAX_CONNECTIONS) p = connections;
andrewboyson 8:5e66a6b4b38c 15 return p;
andrewboyson 8:5e66a6b4b38c 16 }
andrewboyson 8:5e66a6b4b38c 17
andrewboyson 5:ee5489ee1117 18 static void zeroConnection(struct TlsConnection* p)
andrewboyson 5:ee5489ee1117 19 {
andrewboyson 5:ee5489ee1117 20 p->id = 0;
andrewboyson 5:ee5489ee1117 21 p->lastUsed = 0;
andrewboyson 5:ee5489ee1117 22 p->toDo = 0;
andrewboyson 5:ee5489ee1117 23 p->session = 0;
andrewboyson 8:5e66a6b4b38c 24 Sha256Start(&p->handshakeSha); //This just clears any information previously calculated
andrewboyson 6:819c17738dc2 25 p->clientEncrypted = false;
andrewboyson 6:819c17738dc2 26 p->serverEncrypted = false;
andrewboyson 6:819c17738dc2 27 for (int i = 0; i < TLS_RANDOM_SIZE; i++) p->clientRandom[i] = 0;
andrewboyson 6:819c17738dc2 28 for (int i = 0; i < TLS_RANDOM_SIZE; i++) p->serverRandom[i] = 0;
andrewboyson 8:5e66a6b4b38c 29 for (int i = 0; i < TLS_DEFERRED_CONTENT_SIZE; i++) p->deferredContent[i] = 0;
andrewboyson 5:ee5489ee1117 30 }
andrewboyson 5:ee5489ee1117 31
andrewboyson 5:ee5489ee1117 32 struct TlsConnection* TlsConnectionNew(int connectionId) //Never fails so never returns NULL
andrewboyson 5:ee5489ee1117 33 {
andrewboyson 5:ee5489ee1117 34 struct TlsConnection* p;
andrewboyson 5:ee5489ee1117 35
andrewboyson 5:ee5489ee1117 36 //Look for an existing connection
andrewboyson 5:ee5489ee1117 37 for (p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 38 {
andrewboyson 5:ee5489ee1117 39 if (p->id == connectionId) goto end;
andrewboyson 5:ee5489ee1117 40 }
andrewboyson 5:ee5489ee1117 41
andrewboyson 5:ee5489ee1117 42 //look for an empty connection
andrewboyson 5:ee5489ee1117 43 {
andrewboyson 5:ee5489ee1117 44 struct TlsConnection* pOldest = 0;
andrewboyson 5:ee5489ee1117 45 uint32_t ageOldest = 0;
andrewboyson 5:ee5489ee1117 46 for (p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 47 {
andrewboyson 5:ee5489ee1117 48 if (!p->id) goto end;
andrewboyson 5:ee5489ee1117 49
andrewboyson 5:ee5489ee1117 50 //Otherwise record the oldest and keep going
andrewboyson 5:ee5489ee1117 51 uint32_t age = MsTimerCount - p->lastUsed;
andrewboyson 5:ee5489ee1117 52 if (age >= ageOldest)
andrewboyson 5:ee5489ee1117 53 {
andrewboyson 5:ee5489ee1117 54 ageOldest = age;
andrewboyson 5:ee5489ee1117 55 pOldest = p;
andrewboyson 5:ee5489ee1117 56 }
andrewboyson 5:ee5489ee1117 57 }
andrewboyson 5:ee5489ee1117 58
andrewboyson 5:ee5489ee1117 59 //No empty ones found so use the oldest
andrewboyson 5:ee5489ee1117 60 p = pOldest;
andrewboyson 5:ee5489ee1117 61 }
andrewboyson 5:ee5489ee1117 62
andrewboyson 5:ee5489ee1117 63 end:
andrewboyson 5:ee5489ee1117 64 zeroConnection(p);
andrewboyson 5:ee5489ee1117 65 p->id = connectionId;
andrewboyson 5:ee5489ee1117 66 p->lastUsed = MsTimerCount;
andrewboyson 5:ee5489ee1117 67 return p;
andrewboyson 5:ee5489ee1117 68 }
andrewboyson 5:ee5489ee1117 69 struct TlsConnection* TlsConnectionOrNull(int connectionId)
andrewboyson 5:ee5489ee1117 70 {
andrewboyson 5:ee5489ee1117 71 for (struct TlsConnection* p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 72 {
andrewboyson 5:ee5489ee1117 73 if (p->id == connectionId)
andrewboyson 5:ee5489ee1117 74 {
andrewboyson 5:ee5489ee1117 75 p->lastUsed = MsTimerCount;
andrewboyson 5:ee5489ee1117 76 return p;
andrewboyson 5:ee5489ee1117 77 }
andrewboyson 5:ee5489ee1117 78 }
andrewboyson 5:ee5489ee1117 79 return NULL;
andrewboyson 5:ee5489ee1117 80 }
andrewboyson 5:ee5489ee1117 81 void TlsConnectionReset(int connectionId)
andrewboyson 5:ee5489ee1117 82 {
andrewboyson 5:ee5489ee1117 83 for (struct TlsConnection* p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 84 {
andrewboyson 5:ee5489ee1117 85 if (p->id == connectionId) zeroConnection(p);
andrewboyson 5:ee5489ee1117 86 }
andrewboyson 5:ee5489ee1117 87 }
andrewboyson 8:5e66a6b4b38c 88