Andrew Boyson / crypto

A simple library to support serving https.

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tls/tls-connection.c@24:cb43290fc439, 2020-04-01 (annotated)

Committer:
andrewboyson
Date:
Wed Apr 01 12:48:52 2020 +0000
Revision:
24:cb43290fc439
Parent:
17:93feb2a51d58 
Added check so that if the client closes the TCP connection before the TLS connection is established then respond that we have finished and the TCP connection is to be closed.

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 10:e269fd7b9500 20 p->id = 0;
andrewboyson 10:e269fd7b9500 21 p->lastUsed = 0;
andrewboyson 10:e269fd7b9500 22 p->toDo = 0;
andrewboyson 10:e269fd7b9500 23 p->sessionId = 0;
andrewboyson 14:03a0b8fd6ddc 24 p->resume = false;
andrewboyson 8:5e66a6b4b38c 25 Sha256Start(&p->handshakeSha); //This just clears any information previously calculated
andrewboyson 6:819c17738dc2 26 p->clientEncrypted = false;
andrewboyson 6:819c17738dc2 27 p->serverEncrypted = false;
andrewboyson 17:93feb2a51d58 28 for (int i = 0; i < TLS_LENGTH_RANDOM; i++) p->clientRandom[i] = 0;
andrewboyson 17:93feb2a51d58 29 for (int i = 0; i < TLS_LENGTH_RANDOM; i++) p->serverRandom[i] = 0;
andrewboyson 8:5e66a6b4b38c 30 for (int i = 0; i < TLS_DEFERRED_CONTENT_SIZE; i++) p->deferredContent[i] = 0;
andrewboyson 10:e269fd7b9500 31 p->clientSequence = 0;
andrewboyson 10:e269fd7b9500 32 p->serverSequence = 0;
andrewboyson 10:e269fd7b9500 33 p->clientPositionInStreamOffset = 0;
andrewboyson 10:e269fd7b9500 34 p->serverPositionInStreamOffset = 0;
andrewboyson 14:03a0b8fd6ddc 35 p->slotPriKeyDecryption = 0;
andrewboyson 5:ee5489ee1117 36 }
andrewboyson 5:ee5489ee1117 37
andrewboyson 10:e269fd7b9500 38 struct TlsConnection* TlsConnectionNew(int id) //Never fails so never returns NULL
andrewboyson 5:ee5489ee1117 39 {
andrewboyson 5:ee5489ee1117 40 struct TlsConnection* p;
andrewboyson 5:ee5489ee1117 41
andrewboyson 5:ee5489ee1117 42 //Look for an existing connection
andrewboyson 5:ee5489ee1117 43 for (p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 44 {
andrewboyson 10:e269fd7b9500 45 if (p->id == id) goto end;
andrewboyson 5:ee5489ee1117 46 }
andrewboyson 5:ee5489ee1117 47
andrewboyson 5:ee5489ee1117 48 //look for an empty connection
andrewboyson 5:ee5489ee1117 49 {
andrewboyson 5:ee5489ee1117 50 struct TlsConnection* pOldest = 0;
andrewboyson 5:ee5489ee1117 51 uint32_t ageOldest = 0;
andrewboyson 5:ee5489ee1117 52 for (p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 53 {
andrewboyson 5:ee5489ee1117 54 if (!p->id) goto end;
andrewboyson 5:ee5489ee1117 55
andrewboyson 5:ee5489ee1117 56 //Otherwise record the oldest and keep going
andrewboyson 5:ee5489ee1117 57 uint32_t age = MsTimerCount - p->lastUsed;
andrewboyson 5:ee5489ee1117 58 if (age >= ageOldest)
andrewboyson 5:ee5489ee1117 59 {
andrewboyson 5:ee5489ee1117 60 ageOldest = age;
andrewboyson 5:ee5489ee1117 61 pOldest = p;
andrewboyson 5:ee5489ee1117 62 }
andrewboyson 5:ee5489ee1117 63 }
andrewboyson 5:ee5489ee1117 64 //No empty ones found so use the oldest
andrewboyson 5:ee5489ee1117 65 p = pOldest;
andrewboyson 5:ee5489ee1117 66 }
andrewboyson 10:e269fd7b9500 67
andrewboyson 5:ee5489ee1117 68
andrewboyson 5:ee5489ee1117 69 end:
andrewboyson 5:ee5489ee1117 70 zeroConnection(p);
andrewboyson 10:e269fd7b9500 71 p->id = id;
andrewboyson 5:ee5489ee1117 72 p->lastUsed = MsTimerCount;
andrewboyson 5:ee5489ee1117 73 return p;
andrewboyson 5:ee5489ee1117 74 }
andrewboyson 10:e269fd7b9500 75 struct TlsConnection* TlsConnectionOrNull(int id)
andrewboyson 5:ee5489ee1117 76 {
andrewboyson 5:ee5489ee1117 77 for (struct TlsConnection* p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 78 {
andrewboyson 10:e269fd7b9500 79 if (p->id == id)
andrewboyson 5:ee5489ee1117 80 {
andrewboyson 5:ee5489ee1117 81 p->lastUsed = MsTimerCount;
andrewboyson 5:ee5489ee1117 82 return p;
andrewboyson 5:ee5489ee1117 83 }
andrewboyson 5:ee5489ee1117 84 }
andrewboyson 5:ee5489ee1117 85 return NULL;
andrewboyson 5:ee5489ee1117 86 }
andrewboyson 10:e269fd7b9500 87 void TlsConnectionReset(int id)
andrewboyson 5:ee5489ee1117 88 {
andrewboyson 5:ee5489ee1117 89 for (struct TlsConnection* p = connections; p < connections + MAX_CONNECTIONS; p++)
andrewboyson 5:ee5489ee1117 90 {
andrewboyson 10:e269fd7b9500 91 if (p->id == id) zeroConnection(p);
andrewboyson 5:ee5489ee1117 92 }
andrewboyson 5:ee5489ee1117 93 }
andrewboyson 8:5e66a6b4b38c 94