cell/net/tls.c

#include "cell.h"

#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <stdio.h>

#if defined(__APPLE__)
/* SecureTransport — deprecated but functional, no external deps */
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
#include <Security/Security.h>
#include <Security/SecureTransport.h>
#include <sys/socket.h>
#include <unistd.h>
#include <poll.h>

typedef struct {
  SSLContextRef ssl;
  int fd;
} tls_ctx;

static void tls_ctx_free(JSRuntime *rt, tls_ctx *ctx) {
  if (!ctx) return;
  if (ctx->ssl) {
    SSLClose(ctx->ssl);
    CFRelease(ctx->ssl);
  }
  if (ctx->fd >= 0)
    close(ctx->fd);
  free(ctx);
}

QJSCLASS(tls_ctx,)

static OSStatus tls_read_cb(SSLConnectionRef conn, void *data, size_t *len) {
  int fd = *(const int *)conn;
  size_t requested = *len;
  size_t total = 0;
  while (total < requested) {
    ssize_t n = read(fd, (char *)data + total, requested - total);
    if (n > 0) {
      total += n;
    } else if (n == 0) {
      *len = total;
      return errSSLClosedGraceful;
    } else {
      if (errno == EAGAIN || errno == EWOULDBLOCK) {
        *len = total;
        return (total > 0) ? noErr : errSSLWouldBlock;
      }
      *len = total;
      return errSSLClosedAbort;
    }
  }
  *len = total;
  return noErr;
}

static OSStatus tls_write_cb(SSLConnectionRef conn, const void *data, size_t *len) {
  int fd = *(const int *)conn;
  size_t requested = *len;
  size_t total = 0;
  while (total < requested) {
    ssize_t n = write(fd, (const char *)data + total, requested - total);
    if (n > 0) {
      total += n;
    } else if (n == 0) {
      *len = total;
      return errSSLClosedGraceful;
    } else {
      if (errno == EAGAIN || errno == EWOULDBLOCK) {
        *len = total;
        return (total > 0) ? noErr : errSSLWouldBlock;
      }
      *len = total;
      return errSSLClosedAbort;
    }
  }
  *len = total;
  return noErr;
}

/* tls.wrap(fd, hostname) -> ctx */
JSC_CCALL(tls_wrap,
    int fd = -1;
    if (JS_ToInt32(js, &fd, argv[0]) < 0)
        return JS_RaiseDisrupt(js, "tls.wrap: fd must be a number");
    const char *hostname = JS_ToCString(js, argv[1]);
    if (!hostname)
        return JS_RaiseDisrupt(js, "tls.wrap: hostname must be a string");

    tls_ctx *ctx = calloc(1, sizeof(tls_ctx));
    ctx->fd = fd;
    ctx->ssl = SSLCreateContext(NULL, kSSLClientSide, kSSLStreamType);
    if (!ctx->ssl) {
        free(ctx);
        JS_FreeCString(js, hostname);
        return JS_RaiseDisrupt(js, "tls.wrap: SSLCreateContext failed");
    }

    SSLSetIOFuncs(ctx->ssl, tls_read_cb, tls_write_cb);
    SSLSetConnection(ctx->ssl, &ctx->fd);
    SSLSetPeerDomainName(ctx->ssl, hostname, strlen(hostname));
    JS_FreeCString(js, hostname);

    /* Retry handshake on non-blocking sockets (errSSLWouldBlock) */
    OSStatus status;
    for (int attempts = 0; attempts < 200; attempts++) {
        status = SSLHandshake(ctx->ssl);
        if (status == noErr) break;
        if (status != errSSLWouldBlock) break;
        struct pollfd pfd = { .fd = ctx->fd, .events = POLLIN | POLLOUT };
        poll(&pfd, 1, 50);
    }
    if (status != noErr) {
        CFRelease(ctx->ssl);
        ctx->ssl = NULL;
        ctx->fd = -1; /* don't close caller's fd */
        free(ctx);
        return JS_RaiseDisrupt(js, "tls.wrap: handshake failed (status %d)", (int)status);
    }

    return tls_ctx2js(js, ctx);
)

/* tls.send(ctx, data) -> bytes_sent */
JSC_CCALL(tls_send,
    tls_ctx *ctx = js2tls_ctx(js, argv[0]);
    if (!ctx || !ctx->ssl)
        return JS_RaiseDisrupt(js, "tls.send: invalid context");

    size_t len;
    size_t written = 0;
    OSStatus status;

    if (JS_IsText(argv[1])) {
        const char *data = JS_ToCStringLen(js, &len, argv[1]);
        status = SSLWrite(ctx->ssl, data, len, &written);
        JS_FreeCString(js, data);
    } else {
        unsigned char *data = js_get_blob_data(js, &len, argv[1]);
        if (!data)
            return JS_RaiseDisrupt(js, "tls.send: invalid data");
        status = SSLWrite(ctx->ssl, data, len, &written);
    }

    if (status != noErr && status != errSSLWouldBlock)
        return JS_RaiseDisrupt(js, "tls.send: write failed (status %d)", (int)status);

    return JS_NewInt64(js, (int64_t)written);
)

/* tls.recv(ctx, len) -> blob */
JSC_CCALL(tls_recv,
    tls_ctx *ctx = js2tls_ctx(js, argv[0]);
    if (!ctx || !ctx->ssl)
        return JS_RaiseDisrupt(js, "tls.recv: invalid context");

    size_t len = 4096;
    if (argc > 1) len = js2number(js, argv[1]);

    void *out;
    ret = js_new_blob_alloc(js, len, &out);
    if (JS_IsException(ret)) return ret;

    size_t received = 0;
    OSStatus status = SSLRead(ctx->ssl, out, len, &received);

    if (status != noErr && status != errSSLWouldBlock &&
        status != errSSLClosedGraceful) {
        return JS_RaiseDisrupt(js, "tls.recv: read failed (status %d)", (int)status);
    }

    js_blob_stone(ret, received);
    return ret;
)

/* tls.close(ctx) -> null */
JSC_CCALL(tls_close,
    tls_ctx *ctx = js2tls_ctx(js, argv[0]);
    if (!ctx) return JS_NULL;
    if (ctx->ssl) {
        SSLClose(ctx->ssl);
        CFRelease(ctx->ssl);
        ctx->ssl = NULL;
    }
    if (ctx->fd >= 0) {
        close(ctx->fd);
        ctx->fd = -1;
    }
    return JS_NULL;
)

/* tls.fd(ctx) -> number — get underlying fd for on_readable */
JSC_CCALL(tls_fd,
    tls_ctx *ctx = js2tls_ctx(js, argv[0]);
    if (!ctx)
        return JS_RaiseDisrupt(js, "tls.fd: invalid context");
    return JS_NewInt32(js, ctx->fd);
)

/* tls.on_readable(ctx, callback) -> null */
JSC_CCALL(tls_on_readable,
    tls_ctx *ctx = js2tls_ctx(js, argv[0]);
    if (!ctx)
        return JS_RaiseDisrupt(js, "tls.on_readable: invalid context");
    if (!JS_IsFunction(argv[1]))
        return JS_RaiseDisrupt(js, "tls.on_readable: callback must be a function");
    actor_watch_readable(js, ctx->fd, argv[1]);
    return JS_NULL;
)

static const JSCFunctionListEntry js_tls_funcs[] = {
    MIST_FUNC_DEF(tls, wrap, 2),
    MIST_FUNC_DEF(tls, send, 2),
    MIST_FUNC_DEF(tls, recv, 2),
    MIST_FUNC_DEF(tls, close, 1),
    MIST_FUNC_DEF(tls, fd, 1),
    MIST_FUNC_DEF(tls, on_readable, 2),
};

JSValue js_core_net_tls_use(JSContext *js) {
    JS_FRAME(js);
    QJSCLASSPREP_NO_FUNCS(tls_ctx);
    JS_ROOT(mod, JS_NewObject(js));
    JS_SetPropertyFunctionList(js, mod.val, js_tls_funcs, countof(js_tls_funcs));
    JS_RETURN(mod.val);
}

#pragma clang diagnostic pop

#else
/* Stub for non-Apple platforms — TLS not yet implemented */
JSValue js_core_net_tls_use(JSContext *js) {
    return JS_RaiseDisrupt(js, "TLS not available on this platform");
}
#endif