6 files changed, 23 insertions, 8 deletions
diff --git a/modules/forms/repo_form.go b/modules/forms/repo_form.go
index 4a478c7d35..4d37ab072b 100644
--- a/modules/forms/repo_form.go
+++ b/modules/forms/repo_form.go
@@ -698,6 +698,7 @@ type EditRepoFileForm struct {
 	CommitChoice  string `binding:"Required;MaxSize(50)"`
 	NewBranchName string `binding:"GitRefName;MaxSize(100)"`
 	LastCommit    string
+	Signoff       bool
 }
 
 // Validate validates the fields
@@ -733,6 +734,7 @@ type UploadRepoFileForm struct {
 	CommitChoice  string `binding:"Required;MaxSize(50)"`
 	NewBranchName string `binding:"GitRefName;MaxSize(100)"`
 	Files         []string
+	Signoff       bool
 }
 
 // Validate validates the fields
@@ -766,6 +768,7 @@ type DeleteRepoFileForm struct {
 	CommitChoice  string `binding:"Required;MaxSize(50)"`
 	NewBranchName string `binding:"GitRefName;MaxSize(100)"`
 	LastCommit    string
+	Signoff       bool
 }
 
 // Validate validates the fields
diff --git a/modules/repofiles/delete.go b/modules/repofiles/delete.go
index 8343776c47..2b8ddf3cc2 100644
--- a/modules/repofiles/delete.go
+++ b/modules/repofiles/delete.go
@@ -25,6 +25,7 @@ type DeleteRepoFileOptions struct {
 	Author       *IdentityOptions
 	Committer    *IdentityOptions
 	Dates        *CommitDateOptions
+	Signoff      bool
 }
 
 // DeleteRepoFile deletes a file in the given repository
@@ -199,9 +200,9 @@ func DeleteRepoFile(repo *models.Repository, doer *models.User, opts *DeleteRepo
 	// Now commit the tree
 	var commitHash string
 	if opts.Dates != nil {
-		commitHash, err = t.CommitTreeWithDate(author, committer, treeHash, message, opts.Dates.Author, opts.Dates.Committer)
+		commitHash, err = t.CommitTreeWithDate(author, committer, treeHash, message, opts.Signoff, opts.Dates.Author, opts.Dates.Committer)
 	} else {
-		commitHash, err = t.CommitTree(author, committer, treeHash, message)
+		commitHash, err = t.CommitTree(author, committer, treeHash, message, opts.Signoff)
 	}
 	if err != nil {
 		return nil, err
diff --git a/modules/repofiles/temp_repo.go b/modules/repofiles/temp_repo.go
index a02bba65e9..99c62a16c6 100644
--- a/modules/repofiles/temp_repo.go
+++ b/modules/repofiles/temp_repo.go
@@ -185,12 +185,12 @@ func (t *TemporaryUploadRepository) GetLastCommitByRef(ref string) (string, erro
 }
 
 // CommitTree creates a commit from a given tree for the user with provided message
-func (t *TemporaryUploadRepository) CommitTree(author, committer *models.User, treeHash string, message string) (string, error) {
-	return t.CommitTreeWithDate(author, committer, treeHash, message, time.Now(), time.Now())
+func (t *TemporaryUploadRepository) CommitTree(author, committer *models.User, treeHash string, message string, signoff bool) (string, error) {
+	return t.CommitTreeWithDate(author, committer, treeHash, message, signoff, time.Now(), time.Now())
 }
 
 // CommitTreeWithDate creates a commit from a given tree for the user with provided message
-func (t *TemporaryUploadRepository) CommitTreeWithDate(author, committer *models.User, treeHash string, message string, authorDate, committerDate time.Time) (string, error) {
+func (t *TemporaryUploadRepository) CommitTreeWithDate(author, committer *models.User, treeHash string, message string, signoff bool, authorDate, committerDate time.Time) (string, error) {
 	authorSig := author.NewGitSig()
 	committerSig := committer.NewGitSig()
 
@@ -236,6 +236,13 @@ func (t *TemporaryUploadRepository) CommitTreeWithDate(author, committer *models
 		}
 	}
 
+	if signoff {
+		// Signed-off-by
+		_, _ = messageBytes.WriteString("\n")
+		_, _ = messageBytes.WriteString("Signed-off-by: ")
+		_, _ = messageBytes.WriteString(committerSig.String())
+	}
+
 	env = append(env,
 		"GIT_COMMITTER_NAME="+committerSig.Name,
 		"GIT_COMMITTER_EMAIL="+committerSig.Email,
diff --git a/modules/repofiles/update.go b/modules/repofiles/update.go
index a1a9c624d7..0ee1ada34c 100644
--- a/modules/repofiles/update.go
+++ b/modules/repofiles/update.go
@@ -51,6 +51,7 @@ type UpdateRepoFileOptions struct {
 	Author       *IdentityOptions
 	Committer    *IdentityOptions
 	Dates        *CommitDateOptions
+	Signoff      bool
 }
 
 func detectEncodingAndBOM(entry *git.TreeEntry, repo *models.Repository) (string, bool) {
@@ -417,9 +418,9 @@ func CreateOrUpdateRepoFile(repo *models.Repository, doer *models.User, opts *Up
 	// Now commit the tree
 	var commitHash string
 	if opts.Dates != nil {
-		commitHash, err = t.CommitTreeWithDate(author, committer, treeHash, message, opts.Dates.Author, opts.Dates.Committer)
+		commitHash, err = t.CommitTreeWithDate(author, committer, treeHash, message, opts.Signoff, opts.Dates.Author, opts.Dates.Committer)
 	} else {
-		commitHash, err = t.CommitTree(author, committer, treeHash, message)
+		commitHash, err = t.CommitTree(author, committer, treeHash, message, opts.Signoff)
 	}
 	if err != nil {
 		return nil, err
diff --git a/modules/repofiles/upload.go b/modules/repofiles/upload.go
index e3ec48ec0f..c261e188c1 100644
--- a/modules/repofiles/upload.go
+++ b/modules/repofiles/upload.go
@@ -24,6 +24,7 @@ type UploadRepoFileOptions struct {
 	TreePath     string
 	Message      string
 	Files        []string // In UUID format.
+	Signoff      bool
 }
 
 type uploadInfo struct {
@@ -143,7 +144,7 @@ func UploadRepoFiles(repo *models.Repository, doer *models.User, opts *UploadRep
 	committer := doer
 
 	// Now commit the tree
-	commitHash, err := t.CommitTree(author, committer, treeHash, opts.Message)
+	commitHash, err := t.CommitTree(author, committer, treeHash, opts.Message, opts.Signoff)
 	if err != nil {
 		return err
 	}
diff --git a/modules/structs/repo_file.go b/modules/structs/repo_file.go
index c34923e389..71733c90e7 100644
--- a/modules/structs/repo_file.go
+++ b/modules/structs/repo_file.go
@@ -17,6 +17,8 @@ type FileOptions struct {
 	Author    Identity          `json:"author"`
 	Committer Identity          `json:"committer"`
 	Dates     CommitDateOptions `json:"dates"`
+	// Add a Signed-off-by trailer by the committer at the end of the commit log message.
+	Signoff bool `json:"signoff"`
 }
 
 // CreateFileOptions options for creating files