Mercurial > hg
view mercurial/exewrapper.c @ 31290:f819aa9dbbf9
sslutil: issue warning when [hostfingerprint] is used
Mercurial 3.9 added the [hostsecurity] section, which is better
than [hostfingerprints] in every way.
One of the ways that [hostsecurity] is better is that it supports
SHA-256 and SHA-512 fingerprints, not just SHA-1 fingerprints.
The world is moving away from SHA-1 because it is borderline
secure. Mercurial should be part of that movement.
This patch adds a warning when a valid SHA-1 fingerprint from
the [hostfingerprints] section is being used. The warning informs
users to switch to [hostsecurity]. It even prints the config
option they should set. It uses the SHA-256 fingerprint because
recommending a SHA-1 fingerprint in 2017 would be ill-advised.
The warning will print itself on every connection to a server until
it is fixed. There is no way to suppress the warning. I admit this
is annoying. But given the security implications of sticking with
SHA-1, I think this is justified. If this patch is accepted,
I'll likely send a follow-up to start warning on SHA-1
certificates in [hostsecurity] as well. Then sometime down
the road, we can drop support for SHA-1 fingerprints.
Credit for this idea comes from timeless in issue 5466.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Thu, 09 Mar 2017 20:33:29 -0800 |
parents | 210bb28ca4fb |
children | 0241dd94ed38 |
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/* exewrapper.c - wrapper for calling a python script on Windows Copyright 2012 Adrian Buehlmann <adrian@cadifra.com> and others This software may be used and distributed according to the terms of the GNU General Public License version 2 or any later version. */ #include <stdio.h> #include <windows.h> #include "hgpythonlib.h" #ifdef __GNUC__ int strcat_s(char *d, size_t n, const char *s) { return !strncat(d, s, n); } int strcpy_s(char *d, size_t n, const char *s) { return !strncpy(d, s, n); } #endif static char pyscript[MAX_PATH + 10]; static char pyhome[MAX_PATH + 10]; static char envpyhome[MAX_PATH + 10]; static char pydllfile[MAX_PATH + 10]; int main(int argc, char *argv[]) { char *p; int ret; int i; int n; char **pyargv; WIN32_FIND_DATA fdata; HANDLE hfind; const char *err; HMODULE pydll; void (__cdecl *Py_SetPythonHome)(char *home); int (__cdecl *Py_Main)(int argc, char *argv[]); if (GetModuleFileName(NULL, pyscript, sizeof(pyscript)) == 0) { err = "GetModuleFileName failed"; goto bail; } p = strrchr(pyscript, '.'); if (p == NULL) { err = "malformed module filename"; goto bail; } *p = 0; /* cut trailing ".exe" */ strcpy_s(pyhome, sizeof(pyhome), pyscript); hfind = FindFirstFile(pyscript, &fdata); if (hfind != INVALID_HANDLE_VALUE) { /* pyscript exists, close handle */ FindClose(hfind); } else { /* file pyscript isn't there, take <pyscript>exe.py */ strcat_s(pyscript, sizeof(pyscript), "exe.py"); } pydll = NULL; /* We first check, that environment variable PYTHONHOME is *not* set. This just mimicks the behavior of the regular python.exe, which uses PYTHONHOME to find its installation directory (if it has been set). Note: Users of HackableMercurial are expected to *not* set PYTHONHOME! */ if (GetEnvironmentVariable("PYTHONHOME", envpyhome, sizeof(envpyhome)) == 0) { /* Environment var PYTHONHOME is *not* set. Let's see if we are running inside a HackableMercurial. */ p = strrchr(pyhome, '\\'); if (p == NULL) { err = "can't find backslash in module filename"; goto bail; } *p = 0; /* cut at directory */ /* check for private Python of HackableMercurial */ strcat_s(pyhome, sizeof(pyhome), "\\hg-python"); hfind = FindFirstFile(pyhome, &fdata); if (hfind != INVALID_HANDLE_VALUE) { /* path pyhome exists, let's use it */ FindClose(hfind); strcpy_s(pydllfile, sizeof(pydllfile), pyhome); strcat_s(pydllfile, sizeof(pydllfile), "\\" HGPYTHONLIB ".dll"); pydll = LoadLibrary(pydllfile); if (pydll == NULL) { err = "failed to load private Python DLL " HGPYTHONLIB ".dll"; goto bail; } Py_SetPythonHome = (void*)GetProcAddress(pydll, "Py_SetPythonHome"); if (Py_SetPythonHome == NULL) { err = "failed to get Py_SetPythonHome"; goto bail; } Py_SetPythonHome(pyhome); } } if (pydll == NULL) { pydll = LoadLibrary(HGPYTHONLIB ".dll"); if (pydll == NULL) { err = "failed to load Python DLL " HGPYTHONLIB ".dll"; goto bail; } } Py_Main = (void*)GetProcAddress(pydll, "Py_Main"); if (Py_Main == NULL) { err = "failed to get Py_Main"; goto bail; } /* Only add the pyscript to the args, if it's not already there. It may already be there, if the script spawned a child process of itself, in the same way as it got called, that is, with the pyscript already in place. So we optionally accept the pyscript as the first argument (argv[1]), letting our exe taking the role of the python interpreter. */ if (argc >= 2 && strcmp(argv[1], pyscript) == 0) { /* pyscript is already in the args, so there is no need to copy the args and we can directly call the python interpreter with the original args. */ return Py_Main(argc, argv); } /* Start assembling the args for the Python interpreter call. We put the name of our exe (argv[0]) in the position where the python.exe canonically is, and insert the pyscript next. */ pyargv = malloc((argc + 5) * sizeof(char*)); if (pyargv == NULL) { err = "not enough memory"; goto bail; } n = 0; pyargv[n++] = argv[0]; pyargv[n++] = pyscript; /* copy remaining args from the command line */ for (i = 1; i < argc; i++) pyargv[n++] = argv[i]; /* argv[argc] is guaranteed to be NULL, so we forward that guarantee */ pyargv[n] = NULL; ret = Py_Main(n, pyargv); /* The Python interpreter call */ free(pyargv); return ret; bail: fprintf(stderr, "abort: %s\n", err); return 255; }