Add First Draft for GlibcImporter

Signed-off-by: Harsh Mishra <hmisraji07@gmail.com>

Author: harsh098

vulnerabilities/importers/__init__.py

@@ -20,6 +20,7 @@
 from vulnerabilities.importers import github
 from vulnerabilities.importers import github_osv
 from vulnerabilities.importers import gitlab
+from vulnerabilities.importers import glibc
 from vulnerabilities.importers import istio
 from vulnerabilities.importers import mozilla
 from vulnerabilities.importers import nginx
@@ -71,6 +72,7 @@
     oss_fuzz.OSSFuzzImporter,
     ruby.RubyImporter,
     github_osv.GithubOSVImporter,
+    glibc.GlibcImporter
 ]
 
 IMPORTERS_REGISTRY = {x.qualified_name: x for x in IMPORTERS_REGISTRY}

vulnerabilities/importers/glibc.py

@@ -0,0 +1,188 @@
+#
+# Copyright (c) nexB Inc. and others. All rights reserved.
+# VulnerableCode is a trademark of nexB Inc.
+# SPDX-License-Identifier: Apache-2.0
+# See http://www.apache.org/licenses/LICENSE-2.0 for the license text.
+# See https://github.com/nexB/vulnerablecode for support or download.
+# See https://aboutcode.org for more information about nexB OSS projects.
+#
+from datetime import datetime
+from pathlib import Path
+from typing import Any
+from typing import Dict
+from typing import Iterable
+from typing import Optional
+
+from packageurl import PackageURL
+from univers.version_range import PURL_TYPE_BY_GITLAB_SCHEME
+from univers.version_range import RANGE_CLASS_BY_SCHEMES
+from univers.version_range import VersionRange
+from univers.versions import SemverVersion
+
+from vulnerabilities.importer import AdvisoryData
+from vulnerabilities.importer import AffectedPackage
+from vulnerabilities.importer import Importer
+from vulnerabilities.importer import Reference
+
+
+class GNUVersion(VersionRange):
+    # TODO: Open PR for this in univers
+    scheme = "gnu"
+    version_class = SemverVersion
+
+
+RANGE_CLASS_BY_SCHEMES["gnu"] = GNUVersion
+PURL_TYPE_BY_GITLAB_SCHEME["gnu"] = "gnu"
+
+RANGE_CLASS_BY_SCHEMES["gnu"] = GNUVersion
+
+
+class GlibcImporter(Importer):
+    repo_url = "git+https://sourceware.org/git/glibc.git"
+    license_url = "https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=LICENSES"
+    spdx_license_expression = "LGPL-2.1-only"
+    importer_name = "Glibc Importer"
+
+    def advisory_data(self) -> Iterable[AdvisoryData]:
+        try:
+            self.vcs_response = self.clone(repo_url=self.repo_url)
+            base_path = Path(self.vcs_response.dest_dir) / "advisories"
+            readme_path = base_path / "README"
+            files = [path for path in base_path.glob("*") if path != readme_path]
+            for file in files:
+                with open(file, "r") as f:
+                    advisory = parse_advisory_data(f.read(), str(file.relative_to(base_path)))
+                    if advisory:
+                        yield advisory
+        finally:
+            if self.vcs_response:
+                self.vcs_response.delete()
+
+
+def parse_advisory_data(glibc_advisory, file_name) -> AdvisoryData:
+    """
+    Parses the provided GLIBC advisory data from the specified file and returns a structured representation containing the essential information.
+
+    Args:
+        glibc_advisory (str): The raw GLIBC advisory data to be parsed.
+        file_name (str): The name of the file containing the advisory data.
+
+    Returns:
+        AdvisoryData: A dictionary-like object encapsulating the parsed advisory data.
+
+    """
+    content = glibc_advisory.split("\n")
+    if content:
+        subject = content[0]
+    line_counter = 2
+    description = ""
+    date = ""
+    cve_id = ""
+    vulnerable_commits = []
+    fix_commits = []
+    for line in content[line_counter:]:
+        if not line.strip():
+            break
+        description += line.strip() + " "
+        line_counter += 1
+    description = description.strip()
+    for line in content[line_counter + 1 :]:
+        if not line.strip():
+            break
+        tag, content = list(x.strip() for x in line.split(":"))
+        match tag:
+            case "CVE-Id":
+                cve_id = content
+            case "Public-Date":
+                date = content
+            case "Vulnerable-Commit":
+                commit, release = content.split("(")
+                release = release.strip(")").strip()
+                commit = commit.strip()
+                vulnerable_commits.append((commit, release))
+            case "Fix-Commit":
+                commit, release = content.split("(")
+                release = release.strip(")").strip()
+                commit = commit.strip()
+                fix_commits.append((commit, release))
+
+    advisory_dict = {
+        "aliases": [cve_id],
+        "affected_packages": "",
+        "date_published": datetime.strptime(date, "%Y-%m-%d"),
+        "summary": description,
+        "references": [
+            Reference(
+                url="https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/" + file_name
+            )
+        ],
+        "url": "https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/" + file_name,
+    }
+
+    purl = PackageURL(type="gnu", name="glibc")
+    min_affected_version: Optional[SemverVersion, str] = ""
+    max_affected_version: Optional[SemverVersion, str] = ""
+    for _, release in vulnerable_commits:
+        if min_affected_version == "" or max_affected_version == "":
+            min_affected_version = SemverVersion(sanitize_version(release))
+            max_affected_version = SemverVersion(sanitize_version(release))
+        else:
+            min_affected_version = (
+                SemverVersion(sanitize_version(release))
+                if SemverVersion(sanitize_version(release)) < min_affected_version
+                else min_affected_version
+            )
+            max_affected_version = (
+                SemverVersion(sanitize_version(release))
+                if SemverVersion(sanitize_version(release)) > max_affected_version
+                else max_affected_version
+            )
+    _, min_fixed_version = min(fix_commits, key=lambda x: SemverVersion(sanitize_version(x[1])))
+    min_fixed_version = SemverVersion(sanitize_version(min_fixed_version))
+    affected_version_range = None
+    if max_affected_version == "" and min_affected_version == "":
+        affected_version_range = None
+    elif max_affected_version == min_affected_version:
+        affected_version_range = VersionRange.from_string(f"vers:gnu/{str(max_affected_version)}")
+    else:
+        affected_version_range = VersionRange.from_string(
+            f"vers:gnu/<={str(max_affected_version)}|>={min_affected_version}"
+        )
+    affected_packages = AffectedPackage(
+        package=purl,
+        affected_version_range=affected_version_range,
+        fixed_version=min_fixed_version,
+    )
+    advisory_dict["affected_packages"] = [affected_packages]
+    resolved_advisory = to_advisory(advisory_dict)
+    return resolved_advisory
+
+
+def sanitize_version(version: str):
+    """
+    Returns the version in Semver Format from Glibc Advisory
+
+    Args:
+        version (str): Version string from advisory
+
+    Returns:
+         str: Version string in Semver Format
+
+    >>> sanitize_version('2.45-12')
+    '2.45.12'
+    """
+    return version.replace("-", ".")
+
+
+def to_advisory(advisory_data: Dict[str, Any]) -> AdvisoryData:
+    """
+    Returns the AdvisoryData object for a given dictionary containing advisory info
+
+    Args:
+        advisory_data: Dict[str, Any]: contains all fields to be passed to the constructor of AdvisoryData
+
+    Returns:
+        AdvisoryData: converted object into AdvisoryData format
+
+    """
+    return AdvisoryData(**advisory_data)

vulnerabilities/tests/test_glibc.py

@@ -0,0 +1,68 @@
+import os
+from datetime import datetime
+from textwrap import dedent
+from unittest import TestCase
+
+from packageurl import PackageURL
+from univers.version_range import VersionRange
+from univers.versions import SemverVersion
+
+from vulnerabilities.importer import AdvisoryData
+from vulnerabilities.importer import AffectedPackage
+from vulnerabilities.importer import Reference
+from vulnerabilities.importers.glibc import parse_advisory_data
+
+BASE_DIR = os.path.dirname(os.path.abspath(__file__))
+TEST_DATA = os.path.join(BASE_DIR, "test_data/glibc")
+
+
+class TestGlibcImporter(TestCase):
+    def test_parse_advisory_data_1(self):
+        test_data = parse_advisory_data(
+            dedent(
+                """syslog: Heap buffer overflow in __vsyslog_internal
+            
+            __vsyslog_internal did not handle a case where printing a SYSLOG_HEADER
+            containing a long program name failed to update the required buffer
+            size, leading to the allocation and overflow of a too-small buffer on
+            the heap.
+            
+            CVE-Id: CVE-2023-6246
+            Public-Date: 2024-01-30
+            Vulnerable-Commit: 52a5be0df411ef3ff45c10c7c308cb92993d15b1 (2.37)
+            Fix-Commit: 6bd0e4efcc78f3c0115e5ea9739a1642807450da (2.39)
+            Fix-Commit: d1a83b6767f68b3cb5b4b4ea2617254acd040c82 (2.36-126)
+            Fix-Commit: 23514c72b780f3da097ecf33a793b7ba9c2070d2 (2.38-42)
+            Fix-Commit: 97a4292aa4a2642e251472b878d0ec4c46a0e59a (2.37-57)
+            Vulnerable-Commit: b0e7888d1fa2dbd2d9e1645ec8c796abf78880b9 (2.36-16)
+            """
+            ),
+            "GLIBC-SA-2023-0001",
+        )
+
+        expected_output = AdvisoryData(
+            **{
+                "aliases": ["CVE-2023-6246"],
+                "affected_packages": [
+                    AffectedPackage(
+                        package=PackageURL(type="gnu", name="glibc"),
+                        affected_version_range=VersionRange.from_string(
+                            f'vers:gnu/>={str(SemverVersion(string="2.36.16"))}|<={SemverVersion(string="2.37")}'
+                        ),
+                        fixed_version=SemverVersion(string="2.36.126"),
+                    )
+                ],
+                "date_published": datetime(2024, 1, 30, 0, 0),
+                "summary": "__vsyslog_internal did not handle a case where printing a SYSLOG_HEADER containing a long program name failed to update the required buffer size, leading to the allocation and overflow of a too-small buffer on the heap.",
+                "references": [
+                    Reference(
+                        reference_id="",
+                        url="https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2023-0001",
+                        severities=[],
+                    )
+                ],
+                "url": "https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2023-0001",
+            }
+        )
+
+        assert expected_output == test_data