Adding upstream version 9.0.0.

Signed-off-by: Daniel Baumann <daniel@debian.org>

1 files changed, 473 insertions, 0 deletions

diff --git a/modules/git/command.go b/modules/git/command.go
new file mode 100644
index 0000000..a3d43aa
--- /dev/null
+++ b/modules/git/command.go
@@ -0,0 +1,473 @@
+// Copyright 2015 The Gogs Authors. All rights reserved.
+// Copyright 2016 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package git
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"runtime"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/modules/git/internal" //nolint:depguard // only this file can use the internal type CmdArg, other files and packages should use AddXxx functions
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/process"
+	"code.gitea.io/gitea/modules/util"
+)
+
+// TrustedCmdArgs returns the trusted arguments for git command.
+// It's mainly for passing user-provided and trusted arguments to git command
+// In most cases, it shouldn't be used. Use AddXxx function instead
+type TrustedCmdArgs []internal.CmdArg
+
+var (
+	// globalCommandArgs global command args for external package setting
+	globalCommandArgs TrustedCmdArgs
+
+	// defaultCommandExecutionTimeout default command execution timeout duration
+	defaultCommandExecutionTimeout = 360 * time.Second
+)
+
+// DefaultLocale is the default LC_ALL to run git commands in.
+const DefaultLocale = "C"
+
+// Command represents a command with its subcommands or arguments.
+type Command struct {
+	prog             string
+	args             []string
+	parentContext    context.Context
+	desc             string
+	globalArgsLength int
+	brokenArgs       []string
+}
+
+func (c *Command) String() string {
+	return c.toString(false)
+}
+
+func (c *Command) toString(sanitizing bool) string {
+	// WARNING: this function is for debugging purposes only. It's much better than old code (which only joins args with space),
+	// It's impossible to make a simple and 100% correct implementation of argument quoting for different platforms.
+	debugQuote := func(s string) string {
+		if strings.ContainsAny(s, " `'\"\t\r\n") {
+			return fmt.Sprintf("%q", s)
+		}
+		return s
+	}
+	a := make([]string, 0, len(c.args)+1)
+	a = append(a, debugQuote(c.prog))
+	for _, arg := range c.args {
+		if sanitizing && (strings.Contains(arg, "://") && strings.Contains(arg, "@")) {
+			a = append(a, debugQuote(util.SanitizeCredentialURLs(arg)))
+		} else {
+			a = append(a, debugQuote(arg))
+		}
+	}
+	return strings.Join(a, " ")
+}
+
+// NewCommand creates and returns a new Git Command based on given command and arguments.
+// Each argument should be safe to be trusted. User-provided arguments should be passed to AddDynamicArguments instead.
+func NewCommand(ctx context.Context, args ...internal.CmdArg) *Command {
+	// Make an explicit copy of globalCommandArgs, otherwise append might overwrite it
+	cargs := make([]string, 0, len(globalCommandArgs)+len(args))
+	for _, arg := range globalCommandArgs {
+		cargs = append(cargs, string(arg))
+	}
+	for _, arg := range args {
+		cargs = append(cargs, string(arg))
+	}
+	return &Command{
+		prog:             GitExecutable,
+		args:             cargs,
+		parentContext:    ctx,
+		globalArgsLength: len(globalCommandArgs),
+	}
+}
+
+// NewCommandContextNoGlobals creates and returns a new Git Command based on given command and arguments only with the specify args and don't care global command args
+// Each argument should be safe to be trusted. User-provided arguments should be passed to AddDynamicArguments instead.
+func NewCommandContextNoGlobals(ctx context.Context, args ...internal.CmdArg) *Command {
+	cargs := make([]string, 0, len(args))
+	for _, arg := range args {
+		cargs = append(cargs, string(arg))
+	}
+	return &Command{
+		prog:          GitExecutable,
+		args:          cargs,
+		parentContext: ctx,
+	}
+}
+
+// SetParentContext sets the parent context for this command
+func (c *Command) SetParentContext(ctx context.Context) *Command {
+	c.parentContext = ctx
+	return c
+}
+
+// SetDescription sets the description for this command which be returned on c.String()
+func (c *Command) SetDescription(desc string) *Command {
+	c.desc = desc
+	return c
+}
+
+// isSafeArgumentValue checks if the argument is safe to be used as a value (not an option)
+func isSafeArgumentValue(s string) bool {
+	return s == "" || s[0] != '-'
+}
+
+// isValidArgumentOption checks if the argument is a valid option (starting with '-').
+// It doesn't check whether the option is supported or not
+func isValidArgumentOption(s string) bool {
+	return s != "" && s[0] == '-'
+}
+
+// AddArguments adds new git arguments (option/value) to the command. It only accepts string literals, or trusted CmdArg.
+// Type CmdArg is in the internal package, so it can not be used outside of this package directly,
+// it makes sure that user-provided arguments won't cause RCE risks.
+// User-provided arguments should be passed by other AddXxx functions
+func (c *Command) AddArguments(args ...internal.CmdArg) *Command {
+	for _, arg := range args {
+		c.args = append(c.args, string(arg))
+	}
+	return c
+}
+
+// AddOptionValues adds a new option with a list of non-option values
+// For example: AddOptionValues("--opt", val) means 2 arguments: {"--opt", val}.
+// The values are treated as dynamic argument values. It equals to: AddArguments("--opt") then AddDynamicArguments(val).
+func (c *Command) AddOptionValues(opt internal.CmdArg, args ...string) *Command {
+	if !isValidArgumentOption(string(opt)) {
+		c.brokenArgs = append(c.brokenArgs, string(opt))
+		return c
+	}
+	c.args = append(c.args, string(opt))
+	c.AddDynamicArguments(args...)
+	return c
+}
+
+// AddGitGrepExpression adds an expression option (-e) to git-grep command
+// It is different from AddOptionValues in that it allows the actual expression
+// to not be filtered out for leading dashes (which is otherwise a security feature
+// of AddOptionValues).
+func (c *Command) AddGitGrepExpression(exp string) *Command {
+	if c.args[len(globalCommandArgs)] != "grep" {
+		panic("function called on a non-grep git program: " + c.args[0])
+	}
+	c.args = append(c.args, "-e", exp)
+	return c
+}
+
+// AddOptionFormat adds a new option with a format string and arguments
+// For example: AddOptionFormat("--opt=%s %s", val1, val2) means 1 argument: {"--opt=val1 val2"}.
+func (c *Command) AddOptionFormat(opt string, args ...any) *Command {
+	if !isValidArgumentOption(opt) {
+		c.brokenArgs = append(c.brokenArgs, opt)
+		return c
+	}
+	// a quick check to make sure the format string matches the number of arguments, to find low-level mistakes ASAP
+	if strings.Count(strings.ReplaceAll(opt, "%%", ""), "%") != len(args) {
+		c.brokenArgs = append(c.brokenArgs, opt)
+		return c
+	}
+	s := fmt.Sprintf(opt, args...)
+	c.args = append(c.args, s)
+	return c
+}
+
+// AddDynamicArguments adds new dynamic argument values to the command.
+// The arguments may come from user input and can not be trusted, so no leading '-' is allowed to avoid passing options.
+// TODO: in the future, this function can be renamed to AddArgumentValues
+func (c *Command) AddDynamicArguments(args ...string) *Command {
+	for _, arg := range args {
+		if !isSafeArgumentValue(arg) {
+			c.brokenArgs = append(c.brokenArgs, arg)
+		}
+	}
+	if len(c.brokenArgs) != 0 {
+		return c
+	}
+	c.args = append(c.args, args...)
+	return c
+}
+
+// AddDashesAndList adds the "--" and then add the list as arguments, it's usually for adding file list
+// At the moment, this function can be only called once, maybe in future it can be refactored to support multiple calls (if necessary)
+func (c *Command) AddDashesAndList(list ...string) *Command {
+	c.args = append(c.args, "--")
+	// Some old code also checks `arg != ""`, IMO it's not necessary.
+	// If the check is needed, the list should be prepared before the call to this function
+	c.args = append(c.args, list...)
+	return c
+}
+
+// ToTrustedCmdArgs converts a list of strings (trusted as argument) to TrustedCmdArgs
+// In most cases, it shouldn't be used. Use NewCommand().AddXxx() function instead
+func ToTrustedCmdArgs(args []string) TrustedCmdArgs {
+	ret := make(TrustedCmdArgs, len(args))
+	for i, arg := range args {
+		ret[i] = internal.CmdArg(arg)
+	}
+	return ret
+}
+
+// RunOpts represents parameters to run the command. If UseContextTimeout is specified, then Timeout is ignored.
+type RunOpts struct {
+	Env               []string
+	Timeout           time.Duration
+	UseContextTimeout bool
+
+	// Dir is the working dir for the git command, however:
+	// FIXME: this could be incorrect in many cases, for example:
+	// * /some/path/.git
+	// * /some/path/.git/gitea-data/data/repositories/user/repo.git
+	// If "user/repo.git" is invalid/broken, then running git command in it will use "/some/path/.git", and produce unexpected results
+	// The correct approach is to use `--git-dir" global argument
+	Dir string
+
+	Stdout, Stderr io.Writer
+
+	// Stdin is used for passing input to the command
+	// The caller must make sure the Stdin writer is closed properly to finish the Run function.
+	// Otherwise, the Run function may hang for long time or forever, especially when the Git's context deadline is not the same as the caller's.
+	// Some common mistakes:
+	// * `defer stdinWriter.Close()` then call `cmd.Run()`: the Run() would never return if the command is killed by timeout
+	// * `go { case <- parentContext.Done(): stdinWriter.Close() }` with `cmd.Run(DefaultTimeout)`: the command would have been killed by timeout but the Run doesn't return until stdinWriter.Close()
+	// * `go { if stdoutReader.Read() err != nil: stdinWriter.Close() }` with `cmd.Run()`: the stdoutReader may never return error if the command is killed by timeout
+	// In the future, ideally the git module itself should have full control of the stdin, to avoid such problems and make it easier to refactor to a better architecture.
+	Stdin io.Reader
+
+	PipelineFunc func(context.Context, context.CancelFunc) error
+}
+
+func commonBaseEnvs() []string {
+	// at the moment, do not set "GIT_CONFIG_NOSYSTEM", users may have put some configs like "receive.certNonceSeed" in it
+	envs := []string{
+		"HOME=" + HomeDir(),        // make Gitea use internal git config only, to prevent conflicts with user's git config
+		"GIT_NO_REPLACE_OBJECTS=1", // ignore replace references (https://git-scm.com/docs/git-replace)
+	}
+
+	// some environment variables should be passed to git command
+	passThroughEnvKeys := []string{
+		"GNUPGHOME", // git may call gnupg to do commit signing
+	}
+	for _, key := range passThroughEnvKeys {
+		if val, ok := os.LookupEnv(key); ok {
+			envs = append(envs, key+"="+val)
+		}
+	}
+	return envs
+}
+
+// CommonGitCmdEnvs returns the common environment variables for a "git" command.
+func CommonGitCmdEnvs() []string {
+	return append(commonBaseEnvs(), []string{
+		"LC_ALL=" + DefaultLocale,
+		"GIT_TERMINAL_PROMPT=0", // avoid prompting for credentials interactively, supported since git v2.3
+	}...)
+}
+
+// CommonCmdServEnvs is like CommonGitCmdEnvs, but it only returns minimal required environment variables for the "gitea serv" command
+func CommonCmdServEnvs() []string {
+	return commonBaseEnvs()
+}
+
+var ErrBrokenCommand = errors.New("git command is broken")
+
+// Run runs the command with the RunOpts
+func (c *Command) Run(opts *RunOpts) error {
+	if len(c.brokenArgs) != 0 {
+		log.Error("git command is broken: %s, broken args: %s", c.String(), strings.Join(c.brokenArgs, " "))
+		return ErrBrokenCommand
+	}
+	if opts == nil {
+		opts = &RunOpts{}
+	}
+
+	// We must not change the provided options
+	timeout := opts.Timeout
+	if timeout <= 0 {
+		timeout = defaultCommandExecutionTimeout
+	}
+
+	if len(opts.Dir) == 0 {
+		log.Debug("git.Command.Run: %s", c)
+	} else {
+		log.Debug("git.Command.RunDir(%s): %s", opts.Dir, c)
+	}
+
+	desc := c.desc
+	if desc == "" {
+		if opts.Dir == "" {
+			desc = fmt.Sprintf("git: %s", c.toString(true))
+		} else {
+			desc = fmt.Sprintf("git(dir:%s): %s", opts.Dir, c.toString(true))
+		}
+	}
+
+	var ctx context.Context
+	var cancel context.CancelFunc
+	var finished context.CancelFunc
+
+	if opts.UseContextTimeout {
+		ctx, cancel, finished = process.GetManager().AddContext(c.parentContext, desc)
+	} else {
+		ctx, cancel, finished = process.GetManager().AddContextTimeout(c.parentContext, timeout, desc)
+	}
+	defer finished()
+
+	startTime := time.Now()
+
+	cmd := exec.CommandContext(ctx, c.prog, c.args...)
+	if opts.Env == nil {
+		cmd.Env = os.Environ()
+	} else {
+		cmd.Env = opts.Env
+	}
+
+	process.SetSysProcAttribute(cmd)
+	cmd.Env = append(cmd.Env, CommonGitCmdEnvs()...)
+	cmd.Dir = opts.Dir
+	cmd.Stdout = opts.Stdout
+	cmd.Stderr = opts.Stderr
+	cmd.Stdin = opts.Stdin
+	if err := cmd.Start(); err != nil {
+		return err
+	}
+
+	if opts.PipelineFunc != nil {
+		err := opts.PipelineFunc(ctx, cancel)
+		if err != nil {
+			cancel()
+			_ = cmd.Wait()
+			return err
+		}
+	}
+
+	err := cmd.Wait()
+	elapsed := time.Since(startTime)
+	if elapsed > time.Second {
+		log.Debug("slow git.Command.Run: %s (%s)", c, elapsed)
+	}
+
+	// We need to check if the context is canceled by the program on Windows.
+	// This is because Windows does not have signal checking when terminating the process.
+	// It always returns exit code 1, unlike Linux, which has many exit codes for signals.
+	if runtime.GOOS == "windows" &&
+		err != nil &&
+		err.Error() == "" &&
+		cmd.ProcessState.ExitCode() == 1 &&
+		ctx.Err() == context.Canceled {
+		return ctx.Err()
+	}
+
+	if err != nil && ctx.Err() != context.DeadlineExceeded {
+		return err
+	}
+
+	return ctx.Err()
+}
+
+type RunStdError interface {
+	error
+	Unwrap() error
+	Stderr() string
+}
+
+type runStdError struct {
+	err    error
+	stderr string
+	errMsg string
+}
+
+func (r *runStdError) Error() string {
+	// the stderr must be in the returned error text, some code only checks `strings.Contains(err.Error(), "git error")`
+	if r.errMsg == "" {
+		r.errMsg = ConcatenateError(r.err, r.stderr).Error()
+	}
+	return r.errMsg
+}
+
+func (r *runStdError) Unwrap() error {
+	return r.err
+}
+
+func (r *runStdError) Stderr() string {
+	return r.stderr
+}
+
+func IsErrorExitCode(err error, code int) bool {
+	var exitError *exec.ExitError
+	if errors.As(err, &exitError) {
+		return exitError.ExitCode() == code
+	}
+	return false
+}
+
+// RunStdString runs the command with options and returns stdout/stderr as string. and store stderr to returned error (err combined with stderr).
+func (c *Command) RunStdString(opts *RunOpts) (stdout, stderr string, runErr RunStdError) {
+	stdoutBytes, stderrBytes, err := c.RunStdBytes(opts)
+	stdout = util.UnsafeBytesToString(stdoutBytes)
+	stderr = util.UnsafeBytesToString(stderrBytes)
+	if err != nil {
+		return stdout, stderr, &runStdError{err: err, stderr: stderr}
+	}
+	// even if there is no err, there could still be some stderr output, so we just return stdout/stderr as they are
+	return stdout, stderr, nil
+}
+
+// RunStdBytes runs the command with options and returns stdout/stderr as bytes. and store stderr to returned error (err combined with stderr).
+func (c *Command) RunStdBytes(opts *RunOpts) (stdout, stderr []byte, runErr RunStdError) {
+	if opts == nil {
+		opts = &RunOpts{}
+	}
+	if opts.Stdout != nil || opts.Stderr != nil {
+		// we must panic here, otherwise there would be bugs if developers set Stdin/Stderr by mistake, and it would be very difficult to debug
+		panic("stdout and stderr field must be nil when using RunStdBytes")
+	}
+	stdoutBuf := &bytes.Buffer{}
+	stderrBuf := &bytes.Buffer{}
+
+	// We must not change the provided options as it could break future calls - therefore make a copy.
+	newOpts := &RunOpts{
+		Env:               opts.Env,
+		Timeout:           opts.Timeout,
+		UseContextTimeout: opts.UseContextTimeout,
+		Dir:               opts.Dir,
+		Stdout:            stdoutBuf,
+		Stderr:            stderrBuf,
+		Stdin:             opts.Stdin,
+		PipelineFunc:      opts.PipelineFunc,
+	}
+
+	err := c.Run(newOpts)
+	stderr = stderrBuf.Bytes()
+	if err != nil {
+		return nil, stderr, &runStdError{err: err, stderr: util.UnsafeBytesToString(stderr)}
+	}
+	// even if there is no err, there could still be some stderr output
+	return stdoutBuf.Bytes(), stderr, nil
+}
+
+// AllowLFSFiltersArgs return globalCommandArgs with lfs filter, it should only be used for tests
+func AllowLFSFiltersArgs() TrustedCmdArgs {
+	// Now here we should explicitly allow lfs filters to run
+	filteredLFSGlobalArgs := make(TrustedCmdArgs, len(globalCommandArgs))
+	j := 0
+	for _, arg := range globalCommandArgs {
+		if strings.Contains(string(arg), "lfs") {
+			j--
+		} else {
+			filteredLFSGlobalArgs[j] = arg
+			j++
+		}
+	}
+	return filteredLFSGlobalArgs[:j]
+}