Gitea setup: Core Rule Set blocks attacks, not ordinary Gitea traffic (closes #198)

The Gitea setup runs the Core Rule Set in block mode. Rules that refused ordinary Gitea requests are switched off only where they misfired: - deploy/gitea/crs-exclusions.conf, loaded through the new setting SWWAF_CORE_RULE_SET_EXCLUSIONS_FILE, covers Gitea's search, file-name and branch-name fields, Referer, and file paths; - smallwebwaf's defaults gain a seventh change: the registry upload path's from parameter skips 932260. A file that cannot be read, does not parse or names an id from 900000 to 900999 stops servewaf at start. internal/waf's tests and script/gitea-setup send the recorded requests in internal/waf/testdata/gitea-requests.txt and three attacks. Model: opus-5-5
2026-11-06 19:15:51 +00:00
parent 21cac70b50
commit 7e26fe37bc
17 changed files with 806 additions and 239 deletions
@@ -0,0 +1,288 @@
+# Ordinary gitea requests, one path and query per line, that the Core Rule Set
+# must let through with deploy/gitea/crs-exclusions.conf. The tests of
+# internal/waf inspect each, and script/gitea-setup sends each to gitea through
+# the setup.
+
+# Searches with ordinary words and symbols.
+/owner/repo/search?q=package.json
+/owner/repo/search?q=.gitignore
+/owner/repo/search?q=docker-compose.yml
+/owner/repo/search?q=python3
+/owner/repo/search?q=ssh%20key
+/owner/repo/search?q=feat%2Fdocker-support
+/owner/repo/search?q=ls%20-la
+/owner/repo/search?q=sed%20-i
+/owner/repo/search?q=%2Fbin%2Fsh
+/owner/repo/search?q=%60make%20check%60
+/owner/repo/search?q=%60whoami%60
+/owner/repo/search?q=fetch%28
+/owner/repo/search?q=%24%7BVAR%7D
+/owner/repo/search?q=%24%28pwd%29
+/owner/repo/search?q=process.env
+/owner/repo/search?q=%3Cimg%20src%3D
+/owner/repo/search?q=%3Cscript%3E
+/owner/repo/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/search?q=union%20select
+/owner/repo/search?q=http%3A%2F%2F127.0.0.1%3A8080
+/owner/repo/search?q=..%2F
+/owner/repo/search?q=%2Fetc%2Fpasswd
+/owner/repo/search?q=eval%28
+/owner/repo/search?q=chmod%20%2Bx
+/owner/repo/search?q=echo%20%24PATH
+/owner/repo/search?q=java.lang.Runtime
+/owner/repo/search?q=document.cookie
+/owner/repo/search?q=alert%281%29
+/owner/repo/search?q=__proto__
+/owner/repo/search?q=C%3A%5CWindows%5CSystem32
+/owner/repo/search?q=Invoke-WebRequest
+/owner/repo/search?q=if%20%28a%20%3D%3D%20b%29%20%7B
+/owner/repo/search?q=sudo%20apt%20install
+/owner/repo/search?q=~%2F.ssh%2Fconfig
+/owner/repo/search?q=.htaccess
+/explore/repos?q=SELECT%20%2A%20FROM%20users%20WHERE
+/explore/repos?q=%3Cimg%20src%3D
+/explore/code?q=SELECT%20%2A%20FROM%20users%20WHERE
+/explore/code?q=%3Cimg%20src%3D
+/owner/repo/issues?type=all&state=open&q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/issues?type=all&state=open&q=%3Cimg%20src%3D
+/owner/repo/pulls?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/pulls?q=%3Cimg%20src%3D
+/issues?type=your_repositories&q=SELECT%20%2A%20FROM%20users%20WHERE
+/issues?type=your_repositories&q=%3Cimg%20src%3D
+/owner/repo/commits/branch/main/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/commits/branch/main/search?q=%3Cimg%20src%3D
+/owner/repo/wiki/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/wiki/search?q=%3Cimg%20src%3D
+/owner/repo/branches?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/branches?q=%3Cimg%20src%3D
+/owner/repo/releases?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/repo/releases?q=%3Cimg%20src%3D
+/owner/-/packages?q=SELECT%20%2A%20FROM%20users%20WHERE
+/owner/-/packages?q=%3Cimg%20src%3D
+/user/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/user/search?q=%3Cimg%20src%3D
+/api/v1/repos/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/api/v1/repos/search?q=%3Cimg%20src%3D
+/api/v1/repos/issues/search?q=SELECT%20%2A%20FROM%20users%20WHERE
+/api/v1/repos/issues/search?q=%3Cimg%20src%3D
+/api/v1/repos/owner/repo/issues?q=SELECT%20%2A%20FROM%20users%20WHERE
+/api/v1/repos/owner/repo/issues?q=%3Cimg%20src%3D
+
+# Pages, raw files and edit pages of files, and the API's call for their
+# contents.
+/owner/repo/src/branch/main/package.json
+/owner/repo/raw/branch/main/package.json
+/owner/repo/_edit/main/package.json
+/api/v1/repos/owner/repo/contents/package.json
+/owner/repo/src/branch/main/.gitignore
+/owner/repo/raw/branch/main/.gitignore
+/owner/repo/_edit/main/.gitignore
+/api/v1/repos/owner/repo/contents/.gitignore
+/owner/repo/src/branch/main/docker-compose.yml
+/owner/repo/raw/branch/main/docker-compose.yml
+/owner/repo/_edit/main/docker-compose.yml
+/api/v1/repos/owner/repo/contents/docker-compose.yml
+/owner/repo/src/branch/main/Dockerfile
+/owner/repo/raw/branch/main/Dockerfile
+/owner/repo/_edit/main/Dockerfile
+/api/v1/repos/owner/repo/contents/Dockerfile
+/owner/repo/src/branch/main/.htaccess
+/owner/repo/raw/branch/main/.htaccess
+/owner/repo/_edit/main/.htaccess
+/api/v1/repos/owner/repo/contents/.htaccess
+/owner/repo/src/branch/main/rootfs/etc/passwd
+/owner/repo/raw/branch/main/rootfs/etc/passwd
+/owner/repo/_edit/main/rootfs/etc/passwd
+/api/v1/repos/owner/repo/contents/rootfs/etc/passwd
+/owner/repo/src/branch/main/bin/docker-entrypoint
+/owner/repo/raw/branch/main/bin/docker-entrypoint
+/owner/repo/_edit/main/bin/docker-entrypoint
+/api/v1/repos/owner/repo/contents/bin/docker-entrypoint
+/owner/repo/src/branch/main/scripts/python3-setup.sh
+/owner/repo/raw/branch/main/scripts/python3-setup.sh
+/owner/repo/_edit/main/scripts/python3-setup.sh
+/api/v1/repos/owner/repo/contents/scripts/python3-setup.sh
+/owner/repo/src/branch/main/src/java.base/share/classes/java/lang/Runtime.java
+/owner/repo/raw/branch/main/src/java.base/share/classes/java/lang/Runtime.java
+/owner/repo/_edit/main/src/java.base/share/classes/java/lang/Runtime.java
+/api/v1/repos/owner/repo/contents/src/java.base/share/classes/java/lang/Runtime.java
+/owner/repo/src/branch/main/java.lang.String.md
+/owner/repo/raw/branch/main/java.lang.String.md
+/owner/repo/_edit/main/java.lang.String.md
+/api/v1/repos/owner/repo/contents/java.lang.String.md
+/owner/repo/src/branch/main/META-INF/services/org.apache.commons.logging.LogFactory
+/owner/repo/raw/branch/main/META-INF/services/org.apache.commons.logging.LogFactory
+/owner/repo/_edit/main/META-INF/services/org.apache.commons.logging.LogFactory
+/api/v1/repos/owner/repo/contents/META-INF/services/org.apache.commons.logging.LogFactory
+/owner/repo/src/branch/main/process.env.d.ts
+/owner/repo/raw/branch/main/process.env.d.ts
+/owner/repo/_edit/main/process.env.d.ts
+/api/v1/repos/owner/repo/contents/process.env.d.ts
+/owner/repo/src/branch/main/document.write.js
+/owner/repo/raw/branch/main/document.write.js
+/owner/repo/_edit/main/document.write.js
+/api/v1/repos/owner/repo/contents/document.write.js
+/owner/repo/src/branch/main/test/fixtures/__proto__.json
+/owner/repo/raw/branch/main/test/fixtures/__proto__.json
+/owner/repo/_edit/main/test/fixtures/__proto__.json
+/api/v1/repos/owner/repo/contents/test/fixtures/__proto__.json
+/owner/repo/src/branch/main/install-script.sh
+/owner/repo/raw/branch/main/install-script.sh
+/owner/repo/_edit/main/install-script.sh
+/api/v1/repos/owner/repo/contents/install-script.sh
+/owner/repo/src/branch/main/src/backend/catalog/information_schema.sql
+/owner/repo/raw/branch/main/src/backend/catalog/information_schema.sql
+/owner/repo/_edit/main/src/backend/catalog/information_schema.sql
+/api/v1/repos/owner/repo/contents/src/backend/catalog/information_schema.sql
+/owner/repo/src/branch/main/docs/a%20b.xhtml
+/owner/repo/raw/branch/main/docs/a%20b.xhtml
+/owner/repo/_edit/main/docs/a%20b.xhtml
+/api/v1/repos/owner/repo/contents/docs/a%20b.xhtml
+/owner/repo/src/branch/main/%5Bdraft%5D.md
+/owner/repo/raw/branch/main/%5Bdraft%5D.md
+/owner/repo/_edit/main/%5Bdraft%5D.md
+/api/v1/repos/owner/repo/contents/%5Bdraft%5D.md
+
+# File names in the query string: the commit graph of a file, the API's lists
+# of its commits and of its contents, an issue opened from a template, and the
+# sign-in page on the way to its edit page.
+/owner/repo/graph?file=package.json
+/api/v1/repos/owner/repo/commits?path=package.json
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22package.json%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fpackage.json
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fpackage.json
+/owner/repo/graph?file=.gitignore
+/api/v1/repos/owner/repo/commits?path=.gitignore
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22.gitignore%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2F.gitignore
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2F.gitignore
+/owner/repo/graph?file=docker-compose.yml
+/api/v1/repos/owner/repo/commits?path=docker-compose.yml
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22docker-compose.yml%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fdocker-compose.yml
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fdocker-compose.yml
+/owner/repo/graph?file=.htaccess
+/api/v1/repos/owner/repo/commits?path=.htaccess
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22.htaccess%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2F.htaccess
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2F.htaccess
+/owner/repo/graph?file=rootfs%2Fetc%2Fpasswd
+/api/v1/repos/owner/repo/commits?path=rootfs%2Fetc%2Fpasswd
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22rootfs%2Fetc%2Fpasswd%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Frootfs%2Fetc%2Fpasswd
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Frootfs%2Fetc%2Fpasswd
+/owner/repo/graph?file=bin%2Fdocker-entrypoint
+/api/v1/repos/owner/repo/commits?path=bin%2Fdocker-entrypoint
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22bin%2Fdocker-entrypoint%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fbin%2Fdocker-entrypoint
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fbin%2Fdocker-entrypoint
+/owner/repo/graph?file=scripts%2Fpython3-setup.sh
+/api/v1/repos/owner/repo/commits?path=scripts%2Fpython3-setup.sh
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22scripts%2Fpython3-setup.sh%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fscripts%2Fpython3-setup.sh
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fscripts%2Fpython3-setup.sh
+/owner/repo/graph?file=src%2Fjava.base%2Fshare%2Fclasses%2Fjava%2Flang%2FRuntime.java
+/api/v1/repos/owner/repo/commits?path=src%2Fjava.base%2Fshare%2Fclasses%2Fjava%2Flang%2FRuntime.java
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22src%2Fjava.base%2Fshare%2Fclasses%2Fjava%2Flang%2FRuntime.java%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fsrc%2Fjava.base%2Fshare%2Fclasses%2Fjava%2Flang%2FRuntime.java
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fsrc%2Fjava.base%2Fshare%2Fclasses%2Fjava%2Flang%2FRuntime.java
+/owner/repo/graph?file=java.lang.String.md
+/api/v1/repos/owner/repo/commits?path=java.lang.String.md
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22java.lang.String.md%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fjava.lang.String.md
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fjava.lang.String.md
+/owner/repo/graph?file=META-INF%2Fservices%2Forg.apache.commons.logging.LogFactory
+/api/v1/repos/owner/repo/commits?path=META-INF%2Fservices%2Forg.apache.commons.logging.LogFactory
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22META-INF%2Fservices%2Forg.apache.commons.logging.LogFactory%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2FMETA-INF%2Fservices%2Forg.apache.commons.logging.LogFactory
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2FMETA-INF%2Fservices%2Forg.apache.commons.logging.LogFactory
+/owner/repo/graph?file=process.env.d.ts
+/api/v1/repos/owner/repo/commits?path=process.env.d.ts
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22process.env.d.ts%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fprocess.env.d.ts
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fprocess.env.d.ts
+/owner/repo/graph?file=document.write.js
+/api/v1/repos/owner/repo/commits?path=document.write.js
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22document.write.js%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fdocument.write.js
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fdocument.write.js
+/owner/repo/graph?file=test%2Ffixtures%2F__proto__.json
+/api/v1/repos/owner/repo/commits?path=test%2Ffixtures%2F__proto__.json
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22test%2Ffixtures%2F__proto__.json%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Ftest%2Ffixtures%2F__proto__.json
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Ftest%2Ffixtures%2F__proto__.json
+/owner/repo/graph?file=install-script.sh
+/api/v1/repos/owner/repo/commits?path=install-script.sh
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22install-script.sh%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Finstall-script.sh
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Finstall-script.sh
+/owner/repo/graph?file=src%2Fbackend%2Fcatalog%2Finformation_schema.sql
+/api/v1/repos/owner/repo/commits?path=src%2Fbackend%2Fcatalog%2Finformation_schema.sql
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22src%2Fbackend%2Fcatalog%2Finformation_schema.sql%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fsrc%2Fbackend%2Fcatalog%2Finformation_schema.sql
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fsrc%2Fbackend%2Fcatalog%2Finformation_schema.sql
+/owner/repo/graph?file=docs%2Fa%20b.xhtml
+/api/v1/repos/owner/repo/commits?path=docs%2Fa%20b.xhtml
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22docs%2Fa%20b.xhtml%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2Fdocs%2Fa%20b.xhtml
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2Fdocs%2Fa%20b.xhtml
+/owner/repo/graph?file=%5Bdraft%5D.md
+/api/v1/repos/owner/repo/commits?path=%5Bdraft%5D.md
+/api/v1/repos/owner/repo/file-contents?body=%7B%22files%22%3A%5B%22%5Bdraft%5D.md%22%5D%7D
+/owner/repo/issues/new?template=.gitea%2FISSUE_TEMPLATE%2F%5Bdraft%5D.md
+/user/login?redirect_to=%2Fowner%2Frepo%2F_edit%2Fmain%2F%5Bdraft%5D.md
+
+# Branch and tag names in the query string: deleting a branch, starting a
+# release from a tag, a branch protection rule, a directory listing's last
+# commits, and a container image push that reuses a layer.
+/owner/repo/branches?name=docker-build
+/owner/repo/releases/new?tag=docker-build
+/owner/repo/settings/branches/edit?rule_name=docker-build
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Fdocker-build
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Fdocker-build
+/owner/repo/branches?name=feat%2Fdocker-support
+/owner/repo/releases/new?tag=feat%2Fdocker-support
+/owner/repo/settings/branches/edit?rule_name=feat%2Fdocker-support
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Ffeat%2Fdocker-support
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Ffeat%2Fdocker-support
+/owner/repo/branches?name=renovate%2Fdocker-build-push-action-6.x
+/owner/repo/releases/new?tag=renovate%2Fdocker-build-push-action-6.x
+/owner/repo/settings/branches/edit?rule_name=renovate%2Fdocker-build-push-action-6.x
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Frenovate%2Fdocker-build-push-action-6.x
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Frenovate%2Fdocker-build-push-action-6.x
+/owner/repo/branches?name=python3-migration
+/owner/repo/releases/new?tag=python3-migration
+/owner/repo/settings/branches/edit?rule_name=python3-migration
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Fpython3-migration
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Fpython3-migration
+/owner/repo/branches?name=ansible-roles
+/owner/repo/releases/new?tag=ansible-roles
+/owner/repo/settings/branches/edit?rule_name=ansible-roles
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Fansible-roles
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Fansible-roles
+/owner/repo/branches?name=whoami
+/owner/repo/releases/new?tag=whoami
+/owner/repo/settings/branches/edit?rule_name=whoami
+/owner/repo/lastcommit/main/src?refSubUrl=branch%2Fwhoami
+/v2/owner/app/blobs/uploads/?mount=sha256%3A0000&from=owner%2Fwhoami
+
+# Pages a signed-in user opens.
+/
+/owner/repo
+/owner/repo/issues
+/owner/repo/pulls
+/owner/repo/releases
+/owner/repo/wiki
+/owner/repo/activity
+/owner/repo/branches
+/owner/repo/tags
+/owner/repo/settings
+/owner/repo/actions
+/owner/repo/compare/main...main
+/owner/repo/commits/branch/main
+/owner/repo/archive/main.zip
+/notifications
+/user/settings
+/user/settings/applications
+/explore/repos
+/-/admin
@@ -1,8 +1,9 @@
 // Package waf runs the OWASP Core Rule Set 4.25.0, through Coraza, on the
 // method, the URL with its query and the headers of a request, and on its
-// body while SWWAF_WAF_BODY_LIMIT is set, with the six changes smallwebwaf
-// makes to it, as "Attack detection" under "Settings" in SPEC.md describes
-// them. It reads no response.
+// body while SWWAF_WAF_BODY_LIMIT is set, with the seven changes smallwebwaf
+// makes to it and the exclusions in SWWAF_CORE_RULE_SET_EXCLUSIONS_FILE, as
+// "Attack detection" under "Settings" in SPEC.md describes them. It reads no
+// response.
 //
 // smallwebwaf writes only to its state directory, so Coraza is built with
 // its no_fs_access tag, as the Dockerfile and script/build build it: of a
@@ -11,10 +12,13 @@
 package waf

 import (
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
 	"net/netip"
+	"os"
+	"regexp"
 	"slices"
 	"strconv"
 	"strings"
@@ -29,9 +33,9 @@ import (
 // paranoia level for %d, and bodyDirectives for %s while
 // SWWAF_WAF_BODY_LIMIT is set. Each rule smallwebwaf adds has an id from
 // 900000 to 900999, the ids the Core Rule Set keeps for the rules that set
-// it up, which SWWAF_WAF_DISABLED_RULES refuses, so that no setting
-// switches one off. Coraza joins a line ending in \ to the next, without
-// the spaces at the start of the next.
+// it up, which SWWAF_WAF_DISABLED_RULES and the exclusions file refuse, so
+// that no setting switches one off. Coraza joins a line ending in \ to the
+// next, without the spaces at the start of the next.
 const directives = `
 # The engine only detects. smallwebwaf compares the request's anomaly
 # score with SWWAF_WAF_ANOMALY_THRESHOLD itself, in block and detect mode
@@ -100,6 +104,13 @@ SecRuleUpdateTargetById 932260 "!ARGS:path|!ARGS:files|!ARGS:skip-to|\
 # Inspect.
 SecRuleUpdateTargetById 932340 "!REQUEST_HEADERS:Referer"
 SecRuleUpdateTargetById 944110 "!REQUEST_HEADERS:Referer"
+
+# The seventh: a container image push that reuses a layer names the image
+# it takes the layer from in the query parameter from, which is not
+# checked for command names. 932260 refused the push of a layer from
+# owner/python3-app.
+SecRule REQUEST_FILENAME "@rx ^/v2/.+/blobs/uploads/$" \
+    "id:900500,phase:1,pass,nolog,ctl:ruleRemoveTargetById=932260;ARGS:from"
 `

 // bodyDirectives have the Core Rule Set read the part of a request body
@@ -160,8 +171,20 @@ type Params struct {
 	// BodyLimit is the most of a request body the Core Rule Set reads
 	// (SWWAF_WAF_BODY_LIMIT), 0 while it is off and it reads none.
 	BodyLimit int64
+	// ExclusionsFile is the path of a file of exclusions loaded after the
+	// rest (SWWAF_CORE_RULE_SET_EXCLUSIONS_FILE), "" while there is none.
+	ExclusionsFile string
 }

+// smallwebwafRuleID matches an id from 900000 to 900999, which an
+// exclusions file may not name: those are the ids of smallwebwaf's own
+// rules.
+var smallwebwafRuleID = regexp.MustCompile(`\b900\d{3}\b`)
+
+// errSmallwebwafRuleID is the error of an exclusions file that names an
+// id of smallwebwaf's own rules.
+var errSmallwebwafRuleID = errors.New("an id of smallwebwaf's own rules")
+
 // CoreRuleSet is the Core Rule Set, ready to inspect requests. It is safe
 // for concurrent use.
 type CoreRuleSet struct {
@@ -169,9 +192,11 @@ type CoreRuleSet struct {
 	bodyLimit int64
 }

-// New returns the Core Rule Set with the six changes, at params'
-// paranoia level, without the rules it switches off, and reading request
-// bodies up to params' limit.
+// New returns the Core Rule Set with the seven changes, at params'
+// paranoia level, without the rules it switches off, reading request
+// bodies up to params' limit, and with params' exclusions file loaded
+// last. An exclusions file that cannot be read, does not parse or names
+// an id of smallwebwaf's own rules is an error.
 func New(params Params) (*CoreRuleSet, error) {
 	body := ""
 	if params.BodyLimit > 0 {
@@ -189,9 +214,23 @@ func New(params Params) (*CoreRuleSet, error) {
 		text += "SecRuleRemoveById " + strings.Join(ids, " ") + "\n"
 	}

-	waf, err := coraza.NewWAF(coraza.NewWAFConfig().
-		WithRootFS(coreruleset.FS).
-		WithDirectives(text))
+	config := coraza.NewWAFConfig().WithRootFS(coreruleset.FS).WithDirectives(text)
+
+	if params.ExclusionsFile != "" {
+		exclusions, err := os.ReadFile(params.ExclusionsFile)
+		if err != nil {
+			return nil, fmt.Errorf("read the exclusions file: %w", err)
+		}
+
+		if id := smallwebwafRuleID.Find(exclusions); id != nil {
+			return nil, fmt.Errorf("the exclusions file names %s: %w", id,
+				errSmallwebwafRuleID)
+		}
+
+		config = config.WithDirectives(string(exclusions))
+	}
+
+	waf, err := coraza.NewWAF(config)
 	if err != nil {
 		return nil, fmt.Errorf("load the Core Rule Set: %w", err)
 	}
@@ -5,6 +5,7 @@ import (
 	"net/http/httptest"
 	"net/netip"
 	"net/url"
+	"os"
 	"path/filepath"
 	"reflect"
 	"strconv"
@@ -119,7 +120,7 @@ func atDefaults(t *testing.T) *waf.CoreRuleSet {
 }

 // wantChange checks that crs lets through passes, a gitea request one of
-// the six changes is for, and still finds result in refused, a request
+// the seven changes is for, and still finds result in refused, a request
 // like it that the change is not for.
 func wantChange(
 	t *testing.T, crs *waf.CoreRuleSet, passes, refused request, result waf.Result,
@@ -362,6 +363,126 @@ func TestEachDisabledRuleIsSwitchedOff(t *testing.T) {
 	wantResult(t, newCoreRuleSet(t, 1, 920350, 911100), r, waf.Result{})
 }

+func TestImagePushThatReusesALayerIsNotCheckedForCommandNames(t *testing.T) {
+	t.Parallel()
+
+	crs := atDefaults(t)
+	reuse := "?mount=sha256:0000&from=owner/python3-app"
+
+	wantChange(t, crs, get("/v2/owner/app/blobs/uploads/"+reuse), get("/upload/"+reuse),
+		matched(932260))
+
+	// A command after the image's name is still refused.
+	wantResult(t, crs,
+		get("/v2/owner/app/blobs/uploads/?from=owner/app;cat%20/etc/passwd"),
+		matched(930120, 932160))
+}
+
+// withExclusions returns the Core Rule Set at the defaults, with the
+// exclusions file at path.
+func withExclusions(path string) (*waf.CoreRuleSet, error) {
+	return waf.New(waf.Params{
+		ParanoiaLevel: 1, DisabledRules: defaultDisabledRules, ExclusionsFile: path,
+	})
+}
+
+// exclusionsFile writes text to a file of exclusions and returns its path.
+func exclusionsFile(t *testing.T, text string) string {
+	t.Helper()
+
+	path := filepath.Join(t.TempDir(), "exclusions.conf")
+
+	err := os.WriteFile(path, []byte(text), 0o600)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return path
+}
+
+func TestExclusionsFileIsLoadedAfterTheCoreRuleSet(t *testing.T) {
+	t.Parallel()
+
+	crs, err := withExclusions(exclusionsFile(t,
+		"SecRuleUpdateTargetById 942100 \"!ARGS:id\"\n"))
+	if err != nil {
+		t.Fatalf("load the exclusions: %v", err)
+	}
+
+	wantChange(t, crs, get("/?id=1'%20OR%20'1'='1"), get("/?q=1'%20OR%20'1'='1"),
+		matched(942100))
+}
+
+func TestExclusionsFileThatCannotBeUsedIsAnError(t *testing.T) {
+	t.Parallel()
+
+	for _, path := range []string{
+		filepath.Join(t.TempDir(), "missing.conf"),
+		exclusionsFile(t, "SecNoSuchDirective On\n"),
+		// smallwebwaf's own rules may not be switched off or changed.
+		exclusionsFile(t, "SecRuleRemoveById 900300\n"),
+		exclusionsFile(t, "SecRuleUpdateTargetById 900500 \"!ARGS:x\"\n"),
+	} {
+		_, err := withExclusions(path)
+		if err == nil {
+			t.Errorf("%s loaded", path)
+		}
+	}
+}
+
+// giteaRequests returns the targets of the recorded ordinary gitea requests
+// in testdata, which script/gitea-setup sends too.
+func giteaRequests(t *testing.T) []string {
+	t.Helper()
+
+	text, err := os.ReadFile(filepath.Join("testdata", "gitea-requests.txt"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var targets []string
+
+	for line := range strings.Lines(string(text)) {
+		line = strings.TrimSpace(line)
+		if line != "" && !strings.HasPrefix(line, "#") {
+			targets = append(targets, line)
+		}
+	}
+
+	return targets
+}
+
+func TestGiteaExclusionsLetOrdinaryGiteaRequestsThroughAndRefuseAttacks(t *testing.T) {
+	t.Parallel()
+
+	crs, err := withExclusions(filepath.Join("..", "..", "deploy", "gitea",
+		"crs-exclusions.conf"))
+	if err != nil {
+		t.Fatalf("load gitea's exclusions: %v", err)
+	}
+
+	const threshold = 5 // SWWAF_WAF_ANOMALY_THRESHOLD's default
+
+	// Each with the Referer of a page that names the same, as a page
+	// opened from it has.
+	for _, target := range giteaRequests(t) {
+		r := get(target, "Referer: http://git.example"+target)
+		if got := inspect(t, crs, r); got.Score >= threshold {
+			t.Errorf("%s refused: %+v", target, got)
+		}
+	}
+
+	for _, attack := range []string{
+		"/owner/repo?id=1'%20OR%20'1'='1",
+		"/owner/repo?id=..%2Fcustom%2Fconf%2Fapp.ini",
+		"/owner/repo?id=%3Cscript%3Ealert(1)%3C%2Fscript%3E",
+	} {
+		if got := inspect(t, crs, get(attack)); got.Score < threshold {
+			t.Errorf("%s let through: %+v", attack, got)
+		}
+	}
+}
+
 // bodyLimit is SWWAF_WAF_BODY_LIMIT in the tests that read bodies.
 const bodyLimit = 8 << 10