René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[Bug]: Setting `text.usetex=True` in `pyplot.rcParams` Raises FIPS Compliance Errors","articleBody":"### Bug summary\n\nIf you use a FIPS (Federal Information Processing Standards) compliant Python install, then you cannot use `pyplot.show` to display a plot with  `plt.rcParams['text.usetex'] = True` due to a `hashlib.md5` call in [texmanager.py](https://github.com/matplotlib/matplotlib/blob/24bb51c834f7e6714e9ad8e24f7edb6c903028fe/lib/matplotlib/texmanager.py#L171).\n\nThis is similar to https://github.com/matplotlib/matplotlib/issues/18192 (and much of this report is modeled off of that)\n\nThere are 3 places in the code that seem to still use `hashlib.md5`:\n\n- https://github.com/matplotlib/matplotlib/blob/24bb51c834f7e6714e9ad8e24f7edb6c903028fe/lib/matplotlib/texmanager.py#L171\n- https://github.com/matplotlib/matplotlib/blob/24bb51c834f7e6714e9ad8e24f7edb6c903028fe/lib/matplotlib/sphinxext/mathmpl.py#L149\n- https://github.com/matplotlib/matplotlib/blob/24bb51c834f7e6714e9ad8e24f7edb6c903028fe/lib/matplotlib/testing/compare.py#L49\n\nThere probably isn't a great reason not to replace md5 with sha256 (or something else) in these locations.\n\n### Code for reproduction\n\nThe big requirement here is a FIPS compliant system or at least a Python install compiled to be FIPS compliant. Then the following code will reproduce the error.\n\nTo reproduce,\n\n1. Run `sudo fips-mode-setup --enable \u0026\u0026 sudo reboot` (there may be other methods)\n1. After the reboot I confirmed FIPS mode had been enabled by running `fips-mode-setup --check` and it returned FIPS mode is enabled.\n1. `python3 -m venv .venv`\n1. `./.venv/bin/python -m pip install matplotlib==3.10.0`\n1. `./.venv/bin/python fips_error.py`. The contents of `fips_error.py` is listed below.\n\n```python\nimport matplotlib.pyplot as plt\n\nplt.rcParams['text.usetex'] = True\nfig, ax = plt.subplots()\nplt.text(0, 0, r'$\\hat{\\mathbf{x}}$')\nplt.show()\n```\n\n### Actual outcome\n\n```\n$ python fips_error.py \nException in Tkinter callback\nTraceback (most recent call last):\n  File \"/usr/lib64/python3.11/tkinter/__init__.py\", line 1967, in __call__\n    return self.func(*args)\n           ^^^^^^^^^^^^^^^^\n  File \"/usr/lib64/python3.11/tkinter/__init__.py\", line 861, in callit\n    func(*args)\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/backends/_backend_tk.py\", line 274, in idle_draw\n    self.draw()\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/backends/backend_tkagg.py\", line 10, in draw\n    super().draw()\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/backends/backend_agg.py\", line 382, in draw\n    self.figure.draw(self.renderer)\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/artist.py\", line 94, in draw_wrapper\n    result = draw(artist, renderer, *args, **kwargs)\n             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/artist.py\", line 71, in draw_wrapper\n    return draw(artist, renderer)\n           ^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/figure.py\", line 3257, in draw\n    mimage._draw_list_compositing_images(\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/image.py\", line 134, in _draw_list_compositing_images\n    a.draw(renderer)\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/artist.py\", line 71, in draw_wrapper\n    return draw(artist, renderer)\n           ^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/axes/_base.py\", line 3181, in draw\n    mimage._draw_list_compositing_images(\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/image.py\", line 134, in _draw_list_compositing_images\n    a.draw(renderer)\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/artist.py\", line 71, in draw_wrapper\n    return draw(artist, renderer)\n           ^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/axis.py\", line 1416, in draw\n    tlb1, tlb2 = self._get_ticklabel_bboxes(ticks_to_draw, renderer)\n                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/axis.py\", line 1343, in _get_ticklabel_bboxes\n    return ([tick.label1.get_window_extent(renderer)\n            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/axis.py\", line 1343, in \u003clistcomp\u003e\n    return ([tick.label1.get_window_extent(renderer)\n             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/text.py\", line 969, in get_window_extent\n    bbox, info, descent = self._get_layout(self._renderer)\n                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/text.py\", line 373, in _get_layout\n    _, lp_h, lp_d = _get_text_metrics_with_cache(\n                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/text.py\", line 69, in _get_text_metrics_with_cache\n    return _get_text_metrics_with_cache_impl(\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/text.py\", line 77, in _get_text_metrics_with_cache_impl\n    return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/backends/backend_agg.py\", line 211, in get_text_width_height_descent\n    return super().get_text_width_height_descent(s, prop, ismath)\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/backend_bases.py\", line 566, in get_text_width_height_descent\n    return self.get_texmanager().get_text_width_height_descent(\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/texmanager.py\", line 360, in get_text_width_height_descent\n    dvifile = cls.make_dvi(tex, fontsize)\n              ^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/texmanager.py\", line 276, in make_dvi\n    basefile = cls.get_basefile(tex, fontsize)\n               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/data/users/ktm/matplotlib_test/.venv/lib64/python3.11/site-packages/matplotlib/texmanager.py\", line 171, in get_basefile\n    filehash = hashlib.md5(src.encode('utf-8')).hexdigest()\n               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\nValueError: [digital envelope routines: EVP_DigestInit_ex] disabled for FIPS\n```\n\n### Expected outcome\n\nNo exception related to FIPS and the plot is created.\n\n### Additional information\n\n```\n$ .venv/bin/python -m pip list\nPackage         Version\n--------------- -----------\ncontourpy       1.3.1\ncycler          0.12.1\nfonttools       4.56.0\nkiwisolver      1.4.8\nmatplotlib      3.10.0\nnumpy           2.2.2\npackaging       24.2\npillow          11.1.0\npip             22.3.1\npyparsing       3.2.1\npython-dateutil 2.9.0.post0\nsetuptools      65.5.1\nsix             1.17.0\n```\n\n### Operating system\n\nRHEL 8.10 (with FIPS enabled)\n\n### Matplotlib Version\n\n3.10.0\n\n### Matplotlib Backend\n\ntkagg\n\n### Python version\n\nPython 3.11.9\n","author":{"url":"https://github.com/martinky24","@type":"Person","name":"martinky24"},"datePublished":"2025-02-11T18:25:35.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/29603/matplotlib/issues/29603"}