Add ALPN support based on PR #64 from xnyhps

This commit is contained in:
Bruno Silvestre 2018-08-27 15:10:18 -03:00
parent fdb2fa5f59
commit dea60edf4f
7 changed files with 297 additions and 2 deletions

27
samples/alpn/client.lua Normal file
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@ -0,0 +1,27 @@
--
-- Public domain
--
local socket = require("socket")
local ssl = require("ssl")
local params = {
mode = "client",
protocol = "tlsv1_2",
key = "../certs/clientAkey.pem",
certificate = "../certs/clientA.pem",
cafile = "../certs/rootA.pem",
verify = {"peer", "fail_if_no_peer_cert"},
options = "all",
--alpn = {"foo","bar","baz"}
alpn = "foo"
}
local peer = socket.tcp()
peer:connect("127.0.0.1", 8888)
peer = assert( ssl.wrap(peer, params) )
assert(peer:dohandshake())
print("ALPN", peer:getalpn())
peer:close()

77
samples/alpn/server.lua Normal file
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@ -0,0 +1,77 @@
--
-- Public domain
--
local socket = require("socket")
local ssl = require("ssl")
--
-- Callback that selects one protocol from client's list.
--
local function alpncb01(protocols)
print("--- ALPN protocols from client")
for k, v in ipairs(protocols) do
print(k, v)
end
print("--- Selecting:", protocols[1])
return protocols[1]
end
--
-- Callback that returns a fixed list, ignoring the client's list.
--
local function alpncb02(protocols)
print("--- ALPN protocols from client")
for k, v in ipairs(protocols) do
print(k, v)
end
print("--- Returning a fixed list")
return {"bar", "foo"}
end
--
-- Callback that generates a list as it whishes.
--
local function alpncb03(protocols)
local resp = {}
print("--- ALPN protocols from client")
for k, v in ipairs(protocols) do
print(k, v)
if k%2 ~= 0 then resp[#resp+1] = v end
end
print("--- Returning an odd list")
return resp
end
local params = {
mode = "server",
protocol = "any",
key = "../certs/serverAkey.pem",
certificate = "../certs/serverA.pem",
cafile = "../certs/rootA.pem",
verify = {"peer", "fail_if_no_peer_cert"},
options = "all",
--alpn = alpncb01,
--alpn = alpncb02,
--alpn = alpncb03,
alpn = {"bar", "baz", "foo"},
}
-- [[ SSL context
local ctx = assert(ssl.newcontext(params))
--]]
local server = socket.tcp()
server:setoption('reuseaddr', true)
assert( server:bind("127.0.0.1", 8888) )
server:listen()
local peer = server:accept()
peer = assert( ssl.wrap(peer, ctx) )
assert( peer:dohandshake() )
print("ALPN", peer:getalpn())
peer:close()
server:close()

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@ -65,6 +65,11 @@ LSEC_API int luaopen_ssl_config(lua_State *L)
lua_pushstring(L, "capabilities");
lua_newtable(L);
// ALPN
lua_pushstring(L, "alpn");
lua_pushboolean(L, 1);
lua_rawset(L, -3);
#ifndef OPENSSL_NO_EC
#if defined(SSL_CTRL_SET_ECDH_AUTO) || defined(SSL_CTRL_SET_CURVES_LIST) || defined(SSL_CTX_set1_curves_list)
lua_pushstring(L, "curves_list");

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@ -609,6 +609,91 @@ static int set_curves_list(lua_State *L)
}
#endif
/**
* Set the protocols a client should send for ALPN.
*/
static int set_alpn(lua_State *L)
{
long ret;
size_t len;
p_context ctx = checkctx(L, 1);
const char *str = luaL_checklstring(L, 2, &len);
ret = SSL_CTX_set_alpn_protos(ctx->context, (const unsigned char*)str, len);
if (ret) {
lua_pushboolean(L, 0);
lua_pushfstring(L, "error setting ALPN (%s)", ERR_reason_error_string(ERR_get_error()));
return 2;
}
lua_pushboolean(L, 1);
return 1;
}
/**
* This standard callback calls the server's callback in Lua sapce.
* The server has to return a list in wire-format strings.
* This function uses a helper function to match server and client lists.
*/
static int alpn_cb(SSL *s, const unsigned char **out, unsigned char *outlen,
const unsigned char *in, unsigned int inlen, void *arg)
{
int ret;
size_t server_len;
const char *server;
p_context ctx = (p_context)arg;
lua_State *L = ctx->L;
luaL_getmetatable(L, "SSL:ALPN:Registry");
lua_pushlightuserdata(L, (void*)ctx->context);
lua_gettable(L, -2);
lua_pushlstring(L, (const char*)in, inlen);
lua_call(L, 1, 1);
if (!lua_isstring(L, -1)) {
lua_pop(L, 2);
return SSL_TLSEXT_ERR_NOACK;
}
// Protocol list from server in wire-format string
server = luaL_checklstring(L, -1, &server_len);
ret = SSL_select_next_proto((unsigned char**)out, outlen, (const unsigned char*)server,
server_len, in, inlen);
if (ret != OPENSSL_NPN_NEGOTIATED) {
lua_pop(L, 2);
return SSL_TLSEXT_ERR_NOACK;
}
// Copy the result because lua_pop() can collect the pointer
ctx->alpn = malloc(*outlen);
memcpy(ctx->alpn, (void*)*out, *outlen);
*out = (const unsigned char*)ctx->alpn;
lua_pop(L, 2);
return SSL_TLSEXT_ERR_OK;
}
/**
* Set a callback a server can use to select the next protocol with ALPN.
*/
static int set_alpn_cb(lua_State *L)
{
p_context ctx = checkctx(L, 1);
luaL_getmetatable(L, "SSL:ALPN:Registry");
lua_pushlightuserdata(L, (void*)ctx->context);
lua_pushvalue(L, 2);
lua_settable(L, -3);
SSL_CTX_set_alpn_select_cb(ctx->context, alpn_cb, ctx);
lua_pushboolean(L, 1);
return 1;
}
/**
* Package functions
*/
@ -618,6 +703,8 @@ static luaL_Reg funcs[] = {
{"loadcert", load_cert},
{"loadkey", load_key},
{"checkkey", check_key},
{"setalpn", set_alpn},
{"setalpncb", set_alpn_cb},
{"setcipher", set_cipher},
{"setdepth", set_depth},
{"setdhparam", set_dhparam},
@ -654,6 +741,10 @@ static int meth_destroy(lua_State *L)
lua_pushlightuserdata(L, (void*)ctx->context);
lua_pushnil(L);
lua_settable(L, -3);
luaL_getmetatable(L, "SSL:ALPN:Registry");
lua_pushlightuserdata(L, (void*)ctx->context);
lua_pushnil(L);
lua_settable(L, -3);
SSL_CTX_free(ctx->context);
ctx->context = NULL;
@ -796,6 +887,7 @@ void *lsec_testudata (lua_State *L, int ud, const char *tname) {
LSEC_API int luaopen_ssl_context(lua_State *L)
{
luaL_newmetatable(L, "SSL:DH:Registry"); /* Keep all DH callbacks */
luaL_newmetatable(L, "SSL:ALPN:Registry"); /* Keep all ALPN callbacks */
luaL_newmetatable(L, "SSL:Verify:Registry"); /* Keep all verify flags */
luaL_newmetatable(L, "SSL:Context");
setfuncs(L, meta);

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@ -24,6 +24,7 @@ typedef struct t_context_ {
SSL_CTX *context;
lua_State *L;
DH *dh_param;
void *alpn;
int mode;
} t_context;
typedef t_context* p_context;

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@ -389,6 +389,10 @@ static int meth_handshake(lua_State *L)
DH_free(ctx->dh_param);
ctx->dh_param = NULL;
}
if (ctx->alpn) {
free(ctx->alpn);
ctx->alpn = NULL;
}
if (err == IO_DONE) {
lua_pushboolean(L, 1);
return 1;
@ -799,6 +803,19 @@ static int meth_getsniname(lua_State *L)
return 1;
}
static int meth_getalpn(lua_State *L)
{
unsigned len;
const unsigned char *data;
p_ssl ssl = (p_ssl)luaL_checkudata(L, 1, "SSL:Connection");
SSL_get0_alpn_selected(ssl->ssl, &data, &len);
if (data == NULL && len == 0)
lua_pushnil(L);
else
lua_pushlstring(L, (const char*)data, len);
return 1;
}
static int meth_copyright(lua_State *L)
{
lua_pushstring(L, "LuaSec 0.7 - Copyright (C) 2006-2018 Bruno Silvestre, UFG"
@ -816,6 +833,7 @@ static int meth_copyright(lua_State *L)
*/
static luaL_Reg methods[] = {
{"close", meth_close},
{"getalpn", meth_getalpn},
{"getfd", meth_getfd},
{"getfinished", meth_getfinished},
{"getpeercertificate", meth_getpeercertificate},

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@ -30,6 +30,39 @@ local function optexec(func, param, ctx)
return true
end
--
-- Convert an array of strings to wire-format
--
local function array2wireformat(array)
local str = ""
for k, v in ipairs(array) do
if type(v) ~= "string" then return nil end
local len = #v
if len == 0 then
return nil, "invalid ALPN name (empty string)"
elseif len > 255 then
return nil, "invalid ALPN name (length > 255)"
end
str = str .. string.char(len) .. v
end
if str == "" then return nil, "invalid ALPN list (empty)" end
return str
end
--
-- Convert wire-string format to array
--
local function wireformat2array(str)
local i = 1
local array = {}
while i < #str do
local len = str:byte(i)
array[#array + 1] = str:sub(i + 1, i + len)
i = i + len + 1
end
return array
end
--
--
--
@ -113,6 +146,48 @@ local function newcontext(cfg)
if not succ then return nil, msg end
end
-- ALPN
if cfg.mode == "server" and cfg.alpn then
if type(cfg.alpn) == "function" then
local alpncb = cfg.alpn
-- This callback function has to return one value only
succ, msg = context.setalpncb(ctx, function(str)
local protocols = alpncb(wireformat2array(str))
if type(protocols) == "string" then
protocols = { protocols }
elseif type(protocols) ~= "table" then
return nil
end
return (array2wireformat(protocols)) -- use "()" to drop error message
end)
if not succ then return nil, msg end
elseif type(cfg.alpn) == "table" then
local protocols = cfg.alpn
-- check if array is valid before use it
succ, msg = array2wireformat(protocols)
if not succ then return nil, msg end
-- This callback function has to return one value only
succ, msg = context.setalpncb(ctx, function()
return (array2wireformat(protocols)) -- use "()" to drop error message
end)
if not succ then return nil, msg end
else
return nil, "invalid ALPN parameter"
end
elseif cfg.mode == "client" and cfg.alpn then
local alpn
if type(cfg.alpn) == "string" then
alpn, msg = array2wireformat({ cfg.alpn })
elseif type(cfg.alpn) == "table" then
alpn, msg = array2wireformat(cfg.alpn)
else
return nil, "invalid ALPN parameter"
end
if not alpn then return nil, msg end
succ, msg = context.setalpn(ctx, alpn)
if not succ then return nil, msg end
end
return ctx
end