STRLCPY/reverse_ssh

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internal/client/handlers/session.go

		skipped 7 lines
8	8		"strings"
9	9
10	10		"github.com/NHAS/reverse_ssh/internal"
	11	+	"github.com/NHAS/reverse_ssh/internal/client/handlers/subsystems"
11	12		"github.com/NHAS/reverse_ssh/pkg/logger"
12		-	"github.com/pkg/sftp"
13	13		"golang.org/x/crypto/ssh"
14	14		)
15	15
		skipped 19 lines
35	35
36	36		case "subsystem":
37	37
38		-	if !(len(req.Payload) > 4 && string(req.Payload[4:]) == "sftp") {
39		-	req.Reply(false, []byte("Unknown subsystem"))
40		-	log.Warning("unknown subsystem '%s' ", req.Payload)
41		-	}
42		-
43		-	server, err := sftp.NewServer(connection)
	38	+	err := subsystems.RunSubsystems(connection, req)
44	39		if err != nil {
45		-	log.Warning("Unable to make server from channel '%s'", err.Error())
46		-	req.Reply(false, []byte(err.Error()))
47		-	return
	40	+	log.Error("subsystem encountered an error: %s", err.Error())
	41	+	fmt.Fprintf(connection, "subsystem error: '%s'", err.Error())
48	42		}
49	43
50		-	req.Reply(true, nil)
51		-
52		-	err = server.Serve()
53		-	if err != io.EOF && err != nil {
54		-	log.Error("sftp server had an error: %s", err.Error())
55		-	}
56	44		return
57	45
58	46		case "exec":
		skipped 87 lines

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internal/client/handlers/subsystems/init.go

1	+	package subsystems
2	+
3	+	import (
4	+	"fmt"
5	+
6	+	"github.com/NHAS/reverse_ssh/internal/terminal"
7	+	"golang.org/x/crypto/ssh"
8	+	)
9	+
10	+	// Enable sftp for both windows and linux
11	+	var subsystems = map[string]subsystem{
12	+	"sftp": new(subSftp),
13	+	"list": new(list),
14	+	}
15	+
16	+	type subsystem interface {
17	+	Execute(arguments terminal.ParsedLine, connection ssh.Channel, subsystemReq *ssh.Request) error
18	+	}
19	+
20	+	func RunSubsystems(connection ssh.Channel, req *ssh.Request) error {
21	+	if len(req.Payload) < 4 {
22	+	return fmt.Errorf("Payload size is too small <4, not enough space for token")
23	+
24	+	}
25	+
26	+	line := terminal.ParseLine(string(req.Payload[4:]), 0)
27	+	if subsys, ok := subsystems[line.Command.Value()]; ok {
28	+
29	+	return subsys.Execute(line, connection, req)
30	+	}
31	+
32	+	req.Reply(false, []byte("Unknown subsystem"))
33	+	return fmt.Errorf("Unknown subsystem '%s'", req.Payload)
34	+	}
35	+

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internal/client/handlers/subsystems/init_linux.go

1	+	package subsystems
2	+
3	+	//Enable setuid and setgid for linux only
4	+	func init() {
5	+	subsystems["setuid"] = new(setuid)
6	+	subsystems["setgid"] = new(setgid)
7	+	}
8	+

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internal/client/handlers/subsystems/init_windows.go

	1	+	package subsystems
	2	+

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internal/client/handlers/subsystems/list.go

1	+	package subsystems
2	+
3	+	import (
4	+	"fmt"
5	+
6	+	"github.com/NHAS/reverse_ssh/internal/terminal"
7	+	"golang.org/x/crypto/ssh"
8	+	)
9	+
10	+	type list bool
11	+
12	+	func (l list) Execute(line terminal.ParsedLine, connection ssh.Channel, subsystemReq ssh.Request) error {
13	+	subsystemReq.Reply(true, nil)
14	+
15	+	for k := range subsystems {
16	+	fmt.Fprintf(connection, "%s\n", k)
17	+	}
18	+
19	+	return nil
20	+	}
21	+

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internal/client/handlers/subsystems/setgid.go

1	+	//go:build linux
2	+
3	+	package subsystems
4	+
5	+	import (
6	+	"fmt"
7	+	"strconv"
8	+	"syscall"
9	+
10	+	"github.com/NHAS/reverse_ssh/internal/terminal"
11	+	"golang.org/x/crypto/ssh"
12	+	)
13	+
14	+	type setgid bool
15	+
16	+	func (su setgid) Execute(line terminal.ParsedLine, connection ssh.Channel, subsystemReq ssh.Request) error {
17	+
18	+	subsystemReq.Reply(true, nil)
19	+
20	+	if len(line.Arguments) != 1 {
21	+	fmt.Fprintf(connection, "setgid only takes one argument, the uid to set rssh to.")
22	+	return nil
23	+	}
24	+
25	+	gid, err := strconv.Atoi(line.Arguments[0].Value())
26	+
27	+	if err != nil {
28	+	fmt.Fprintf(connection, "%s", err.Error())
29	+	return nil
30	+	}
31	+
32	+	return syscall.Setgid(gid)
33	+	}
34	+

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internal/client/handlers/subsystems/setuid.go

1	+	//go:build linux
2	+
3	+	package subsystems
4	+
5	+	import (
6	+	"fmt"
7	+	"strconv"
8	+	"syscall"
9	+
10	+	"github.com/NHAS/reverse_ssh/internal/terminal"
11	+	"golang.org/x/crypto/ssh"
12	+	)
13	+
14	+	type setuid bool
15	+
16	+	func (su setuid) Execute(line terminal.ParsedLine, connection ssh.Channel, subsystemReq ssh.Request) error {
17	+	subsystemReq.Reply(true, nil)
18	+
19	+	if len(line.Arguments) != 1 {
20	+	fmt.Fprintf(connection, "setuid only takes one argument, the uid to set rssh to.")
21	+	return nil
22	+	}
23	+
24	+	uid, err := strconv.Atoi(line.Arguments[0].Value())
25	+
26	+	if err != nil {
27	+	fmt.Fprintf(connection, "%s", err.Error())
28	+	return nil
29	+	}
30	+
31	+	return syscall.Setuid(uid)
32	+	}
33	+

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internal/client/handlers/subsystems/sftp.go

1	+	package subsystems
2	+
3	+	import (
4	+	"fmt"
5	+	"io"
6	+
7	+	"github.com/NHAS/reverse_ssh/internal/terminal"
8	+	"github.com/pkg/sftp"
9	+	"golang.org/x/crypto/ssh"
10	+	)
11	+
12	+	type subSftp bool
13	+
14	+	func (s subSftp) Execute(_ terminal.ParsedLine, connection ssh.Channel, subsystemReq ssh.Request) error {
15	+	server, err := sftp.NewServer(connection)
16	+	if err != nil {
17	+	subsystemReq.Reply(false, []byte(err.Error()))
18	+	return err
19	+	}
20	+
21	+	subsystemReq.Reply(true, nil)
22	+
23	+	err = server.Serve()
24	+	if err != io.EOF && err != nil {
25	+	return fmt.Errorf("sftp server had an error: %s", err.Error())
26	+	}
27	+
28	+	return nil
29	+	}
30	+

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internal/server/handlers/session.go

		skipped 1 lines
2	2
3	3		import (
4	4		"fmt"
	5	+	"io"
5	6
6	7		"github.com/NHAS/reverse_ssh/internal"
	8	+	"github.com/NHAS/reverse_ssh/internal/server/clients"
7	9		"github.com/NHAS/reverse_ssh/internal/server/commands"
	10	+	"github.com/NHAS/reverse_ssh/internal/server/webserver"
8	11		"github.com/NHAS/reverse_ssh/internal/terminal"
	12	+	"github.com/NHAS/reverse_ssh/internal/terminal/autocomplete"
9	13		"github.com/NHAS/reverse_ssh/pkg/logger"
10	14		"golang.org/x/crypto/ssh"
11	15		)
		skipped 52 lines
64	68		// (i.e. no command in the Payload)
65	69		req.Reply(len(req.Payload) == 0, nil)
66	70
67		-	//This blocks so will keep the channel from defer closing
68		-	shell(user, connection, log)
	71	+	term := terminal.NewAdvancedTerminal(connection, user, "catcher$ ")
	72	+
	73	+	term.SetSize(int(user.Pty.Columns), int(user.Pty.Rows))
	74	+
	75	+	term.AddValueAutoComplete(autocomplete.RemoteId, clients.Autocomplete)
	76	+	term.AddValueAutoComplete(autocomplete.WebServerFileIds, webserver.Autocomplete)
	77	+
	78	+	term.AddCommands(commands.CreateCommands(user, log))
	79	+
	80	+	err := term.Run()
	81	+	if err != nil && err != io.EOF {
	82	+	log.Error("Error: %s", err)
	83	+	}
69	84
70	85		return
71	86		//Yes, this is here for a reason future me. Despite the RFC saying "Only one of shell,subsystem, exec can occur per channel" pty-req actuall proceeds all of them
		skipped 21 lines

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internal/server/handlers/shell.go

1	-	package handlers
2	-
3	-	import (
4	-	"fmt"
5	-	"io"
6	-
7	-	"github.com/NHAS/reverse_ssh/internal"
8	-	"github.com/NHAS/reverse_ssh/internal/server/clients"
9	-	"github.com/NHAS/reverse_ssh/internal/server/commands"
10	-	"github.com/NHAS/reverse_ssh/internal/server/webserver"
11	-	"github.com/NHAS/reverse_ssh/internal/terminal"
12	-	"github.com/NHAS/reverse_ssh/internal/terminal/autocomplete"
13	-	"github.com/NHAS/reverse_ssh/pkg/logger"
14	-	"golang.org/x/crypto/ssh"
15	-	)
16	-
17	-	func shell(user *internal.User, connection ssh.Channel, log logger.Logger) error {
18	-	term := terminal.NewAdvancedTerminal(connection, user, "catcher$ ")
19	-
20	-	term.SetSize(int(user.Pty.Columns), int(user.Pty.Rows))
21	-
22	-	term.AddValueAutoComplete(autocomplete.RemoteId, clients.Autocomplete)
23	-	term.AddValueAutoComplete(autocomplete.WebServerFileIds, webserver.Autocomplete)
24	-
25	-	term.AddCommands(commands.CreateCommands(user, log))
26	-
27	-	err := term.Run()
28	-	if err != nil && err != io.EOF {
29	-	fmt.Fprintf(term, "Error: %s\n", err)
30	-	}
31	-
32	-	return err
33	-	}
34	-