SSL

Does Codea support SSL with LuaSocket connections? I’ve been trying to do things that would require that, with no success.

Not so far as I’m aware, but to make a secure connection you don’t need full blown ssl if you have access to both ends initially. I found a lua implementation of rc4 on the web and got that working with Codea.

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-- Usage: Call `rc4` to create a dual-purpose stream. Call the stream to encipher plaintext or decipher ciphertext.
--             
--              Either strings or tables can be passed as arguments, in any order.
--             
--      stream = rc4"Key"                               --      stream = rc4{107,101,121}
--      ciphertext = stream"Plaintext"  --      ciphertext = stream{80,108,97,105,110,116,101,120,116}
--      
--      stream = rc4"Key"                               --      stream = rc4{107,101,121}
--      plaintext = stream(ciphertext)  --      plaintext = stream(ciphertext)
--      
--              Pass `true` as the stream's second argument to force byte-table output. Otherwise, it will return a string.
--             
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function rc4(salt)
        local key = type(salt) == "table" and {unpack(salt)} or {string.byte(salt,1,#salt)}
        local S, j, keylength = {[0] = 0,[1] = 1,[2] = 2,[3] = 3,[4] = 4,[5] = 5,[6] = 6,[7] = 7,[8] = 8,[9] = 9,[10] = 10,[11] = 11,[12] = 12,[13] = 13,[14] = 14,[15] = 15,[16] = 16,[17] = 17,[18] = 18,[19] = 19,[20] = 20,[21] = 21,[22] = 22,[23] = 23,[24] = 24,[25] = 25,[26] = 26,[27] = 27,[28] = 28,[29] = 29,[30] = 30,[31] = 31,[32] = 32,[33] = 33,[34] = 34,[35] = 35,[36] = 36,[37] = 37,[38] = 38,[39] = 39,[40] = 40,[41] = 41,[42] = 42,[43] = 43,[44] = 44,[45] = 45,[46] = 46,[47] = 47,[48] = 48,[49] = 49,[50] = 50,[51] = 51,[52] = 52,[53] = 53,[54] = 54,[55] = 55,[56] = 56,[57] = 57,[58] = 58,[59] = 59,[60] = 60,[61] = 61,[62] = 62,[63] = 63,[64] = 64,[65] = 65,[66] = 66,[67] = 67,[68] = 68,[69] = 69,[70] = 70,[71] = 71,[72] = 72,[73] = 73,[74] = 74,[75] = 75,[76] = 76,[77] = 77,[78] = 78,[79] = 79,[80] = 80,[81] = 81,[82] = 82,[83] = 83,[84] = 84,[85] = 85,[86] = 86,[87] = 87,[88] = 88,[89] = 89,[90] = 90,[91] = 91,[92] = 92,[93] = 93,[94] = 94,[95] = 95,[96] = 96,[97] = 97,[98] = 98,[99] = 99,[100] = 100,[101] = 101,[102] = 102,[103] = 103,[104] = 104,[105] = 105,[106] = 106,[107] = 107,[108] = 108,[109] = 109,[110] = 110,[111] = 111,[112] = 112,[113] = 113,[114] = 114,[115] = 115,[116] = 116,[117] = 117,[118] = 118,[119] = 119,[120] = 120,[121] = 121,[122] = 122,[123] = 123,[124] = 124,[125] = 125,[126] = 126,[127] = 127,[128] = 128,[129] = 129,[130] = 130,[131] = 131,[132] = 132,[133] = 133,[134] = 134,[135] = 135,[136] = 136,[137] = 137,[138] = 138,[139] = 139,[140] = 140,[141] = 141,[142] = 142,[143] = 143,[144] = 144,[145] = 145,[146] = 146,[147] = 147,[148] = 148,[149] = 149,[150] = 150,[151] = 151,[152] = 152,[153] = 153,[154] = 154,[155] = 155,[156] = 156,[157] = 157,[158] = 158,[159] = 159,[160] = 160,[161] = 161,[162] = 162,[163] = 163,[164] = 164,[165] = 165,[166] = 166,[167] = 167,[168] = 168,[169] = 169,[170] = 170,[171] = 171,[172] = 172,[173] = 173,[174] = 174,[175] = 175,[176] = 176,[177] = 177,[178] = 178,[179] = 179,[180] = 180,[181] = 181,[182] = 182,[183] = 183,[184] = 184,[185] = 185,[186] = 186,[187] = 187,[188] = 188,[189] = 189,[190] = 190,[191] = 191,[192] = 192,[193] = 193,[194] = 194,[195] = 195,[196] = 196,[197] = 197,[198] = 198,[199] = 199,[200] = 200,[201] = 201,[202] = 202,[203] = 203,[204] = 204,[205] = 205,[206] = 206,[207] = 207,[208] = 208,[209] = 209,[210] = 210,[211] = 211,[212] = 212,[213] = 213,[214] = 214,[215] = 215,[216] = 216,[217] = 217,[218] = 218,[219] = 219,[220] = 220,[221] = 221,[222] = 222,[223] = 223,[224] = 224,[225] = 225,[226] = 226,[227] = 227,[228] = 228,[229] = 229,[230] = 230,[231] = 231,[232] = 232,[233] = 233,[234] = 234,[235] = 235,[236] = 236,[237] = 237,[238] = 238,[239] = 239,[240] = 240,[241] = 241,[242] = 242,[243] = 243,[244] = 244,[245] = 245,[246] = 246,[247] = 247,[248] = 248,[249] = 249,[250] = 250,[251] = 251,[252] = 252,[253] = 253,[254] = 254,[255] = 255}, 0, #key
        for i = 0, 255 do
                j = (j + S[i] + key[i % keylength + 1]) % 256
                S[i], S[j] = S[j], S[i]
        end
        local i = 0
        j = 0
        return function(plaintext, astable)
                local chars = type(plaintext) == "table" and {unpack(plaintext)} or {string.byte(plaintext,1,#plaintext)}
                for n = 1,#chars do
                        i = (i + 1) % 256
                        j = (j + S[i]) % 256
                        S[i], S[j] = S[j], S[i]
                        chars[n] = (S[(S[i] + S[j]) % 256]) ~ chars[n]
                end
                return astable and chars or string.char(unpack(chars))
        end
end
 
----------------------------------------------------------------------------------
-- Usage: Same as above. Use extra parameter to discard that many keystream bytes.
--
----------------------------------------------------------------------------------
function rc4dropn(salt, dropn)
        local key = type(salt) == "table" and {unpack(salt)} or {string.byte(salt,1,#salt)}
        local S, j, keylength = {[0] = 0,[1] = 1,[2] = 2,[3] = 3,[4] = 4,[5] = 5,[6] = 6,[7] = 7,[8] = 8,[9] = 9,[10] = 10,[11] = 11,[12] = 12,[13] = 13,[14] = 14,[15] = 15,[16] = 16,[17] = 17,[18] = 18,[19] = 19,[20] = 20,[21] = 21,[22] = 22,[23] = 23,[24] = 24,[25] = 25,[26] = 26,[27] = 27,[28] = 28,[29] = 29,[30] = 30,[31] = 31,[32] = 32,[33] = 33,[34] = 34,[35] = 35,[36] = 36,[37] = 37,[38] = 38,[39] = 39,[40] = 40,[41] = 41,[42] = 42,[43] = 43,[44] = 44,[45] = 45,[46] = 46,[47] = 47,[48] = 48,[49] = 49,[50] = 50,[51] = 51,[52] = 52,[53] = 53,[54] = 54,[55] = 55,[56] = 56,[57] = 57,[58] = 58,[59] = 59,[60] = 60,[61] = 61,[62] = 62,[63] = 63,[64] = 64,[65] = 65,[66] = 66,[67] = 67,[68] = 68,[69] = 69,[70] = 70,[71] = 71,[72] = 72,[73] = 73,[74] = 74,[75] = 75,[76] = 76,[77] = 77,[78] = 78,[79] = 79,[80] = 80,[81] = 81,[82] = 82,[83] = 83,[84] = 84,[85] = 85,[86] = 86,[87] = 87,[88] = 88,[89] = 89,[90] = 90,[91] = 91,[92] = 92,[93] = 93,[94] = 94,[95] = 95,[96] = 96,[97] = 97,[98] = 98,[99] = 99,[100] = 100,[101] = 101,[102] = 102,[103] = 103,[104] = 104,[105] = 105,[106] = 106,[107] = 107,[108] = 108,[109] = 109,[110] = 110,[111] = 111,[112] = 112,[113] = 113,[114] = 114,[115] = 115,[116] = 116,[117] = 117,[118] = 118,[119] = 119,[120] = 120,[121] = 121,[122] = 122,[123] = 123,[124] = 124,[125] = 125,[126] = 126,[127] = 127,[128] = 128,[129] = 129,[130] = 130,[131] = 131,[132] = 132,[133] = 133,[134] = 134,[135] = 135,[136] = 136,[137] = 137,[138] = 138,[139] = 139,[140] = 140,[141] = 141,[142] = 142,[143] = 143,[144] = 144,[145] = 145,[146] = 146,[147] = 147,[148] = 148,[149] = 149,[150] = 150,[151] = 151,[152] = 152,[153] = 153,[154] = 154,[155] = 155,[156] = 156,[157] = 157,[158] = 158,[159] = 159,[160] = 160,[161] = 161,[162] = 162,[163] = 163,[164] = 164,[165] = 165,[166] = 166,[167] = 167,[168] = 168,[169] = 169,[170] = 170,[171] = 171,[172] = 172,[173] = 173,[174] = 174,[175] = 175,[176] = 176,[177] = 177,[178] = 178,[179] = 179,[180] = 180,[181] = 181,[182] = 182,[183] = 183,[184] = 184,[185] = 185,[186] = 186,[187] = 187,[188] = 188,[189] = 189,[190] = 190,[191] = 191,[192] = 192,[193] = 193,[194] = 194,[195] = 195,[196] = 196,[197] = 197,[198] = 198,[199] = 199,[200] = 200,[201] = 201,[202] = 202,[203] = 203,[204] = 204,[205] = 205,[206] = 206,[207] = 207,[208] = 208,[209] = 209,[210] = 210,[211] = 211,[212] = 212,[213] = 213,[214] = 214,[215] = 215,[216] = 216,[217] = 217,[218] = 218,[219] = 219,[220] = 220,[221] = 221,[222] = 222,[223] = 223,[224] = 224,[225] = 225,[226] = 226,[227] = 227,[228] = 228,[229] = 229,[230] = 230,[231] = 231,[232] = 232,[233] = 233,[234] = 234,[235] = 235,[236] = 236,[237] = 237,[238] = 238,[239] = 239,[240] = 240,[241] = 241,[242] = 242,[243] = 243,[244] = 244,[245] = 245,[246] = 246,[247] = 247,[248] = 248,[249] = 249,[250] = 250,[251] = 251,[252] = 252,[253] = 253,[254] = 254,[255] = 255}, 0, #key
        for i = 0, 255 do
                j = (j + S[i] + key[i % keylength + 1]) % 256
                S[i], S[j] = S[j], S[i]
        end
        local i = 0
        j = 0
        for n = 1, dropn do
                i = (i + 1) % 256
                j = (j + S[i]) % 256
                S[i],S[j] = S[j],S[i]
        end
        return function(plaintext, astable)
                local chars = type(plaintext) == "table" and {unpack(plaintext)} or {string.byte(plaintext,1,#plaintext)}
                for n = 1,#chars do
                        i = (i + 1) % 256
                        j = (j + S[i]) % 256
                        S[i], S[j] = S[j], S[i]
                        chars[n] = (S[(S[i] + S[j]) % 256]) ~ chars[n]
                end
                return astable and chars or string.char(unpack(chars))
        end
end

This is nice, but be aware that RC4 cipher is considered insecure nowadays.

The basic rc4 is, but the second function - which drops the first n terms of the sequence - is still widely in use and although it may still be flawed, there isn’t a suitable replacement yet (some have been proposed but not sufficiently analysed yet).

That said, I wouldn’t use this for something high-security, but then I wouldn’t use Codea for something high security.