senpai: config: allow specifying an external password cmd v2 SUPERSEDED

Kalyan Sriram: 1
 config: allow specifying an external password cmd

 3 files changed, 36 insertions(+), 6 deletions(-)

[PATCH senpai v2] config: allow specifying an external password cmd Export this patch

Storing passwords in plaintext in your configuration file is dangerous!
This patch adds support for fetching a password from an external
command (i.e. `gpg`, `pass`, `gopass`).
---
Updated the credential execution to run the specified credential helper
command with "sh -c" to allow arbitrary shell commands, as per previous
email. Let me know if this is acceptable or you'd still rather have a
separate shell script file like ~/.config/senpai/password
 README.md        |  2 ++
 config.go        | 19 +++++++++++++++++++
 doc/senpai.5.scd | 21 +++++++++++++++------
 3 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 99c80bd..e451228 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@ cat <<EOF >~/.config/senpai/senpai.yaml
 addr: irc.libera.chat
 nick: senpai
 password: "my password can't be this cute"
+# alternatively, specify a command to fetch your password:
+# passcmd: "gopass show irc/<username>"
 EOF
 go run ./cmd/senpai
 ```
diff --git a/config.go b/config.go
index 2b05e07..03966e8 100644
--- a/config.go
+++ b/config.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
+	"os/exec"
 	"strconv"
 	"strings"
 
@@ -52,6 +53,7 @@ type Config struct {
 	Real     string
 	User     string
 	Password *string
+	Passcmd  string
 	NoTLS    bool `yaml:"no-tls"`
 	Channels []string
 
@@ -88,6 +90,13 @@ func ParseConfig(buf []byte) (cfg Config, err error) {
 	if cfg.Real == "" {
 		cfg.Real = cfg.Nick
 	}
+	if cfg.Passcmd != "" {
+		password, err := RunPasscmd(cfg.Passcmd)
+		if err != nil {
+			return cfg, err
+		}
+		cfg.Password = &password
+	}
 	if cfg.NickColWidth <= 0 {
 		cfg.NickColWidth = 16
 	}
@@ -114,3 +123,13 @@ func LoadConfigFile(filename string) (cfg Config, err error) {
 	}
 	return
 }
+
+func RunPasscmd(command string) (password string, err error) {
+	cmd := exec.Command("sh", "-c", command)
+	stdout, err := cmd.Output()
+	if err == nil {
+		password = strings.TrimSuffix(string(stdout), "\n")
+	}
+
+	return
+}
diff --git a/doc/senpai.5.scd b/doc/senpai.5.scd
index 5658707..49fdac0 100644
--- a/doc/senpai.5.scd
+++ b/doc/senpai.5.scd
@@ -31,7 +31,15 @@ Some settings are required, the others are optional.
 	authentication.  By default, the value of *nick* is used.
 
 *password*
-	Your password, used for SASL authentication.
+	Your password, used for SASL authentication. See also *passcmd*.
+
+*passcmd*
+	Alternatively to providing your SASL authentication password directly in plaintext,
+	you can specify a command to be run to fetch the password at runtime. This is useful
+	if you store your passwords in a separate (probably encrypted) file using `gpg` or
+	a command line password manager such as `pass` or `gopass`. If a *passcmd* is provided,
+	the value of *password* will be ignored and the output of *passcmd* will be used for
+	login.
 
 *channels*
 	A list of channel names that senpai will automatically join at startup and
@@ -125,17 +133,18 @@ addr: irc.libera.chat
 nick: Guest123456
 ```
 
-A more advanced configuration file that enables SASL authentication, sends
-notifications on highlight and decreases the width of the nick column to 12
-(note: _swaymsg_ is specific to sway, a wayland compositor.  Use whatever you
-need to know if the terminal emulator that runs senpai has focus):
+A more advanced configuration file that enables SASL authentication, fetches the password
+from an external program instead of storing in plaintext, sends notifications on highlight
+and decreases the width of the nick column to 12 (note: _swaymsg_ is specific to sway,
+a wayland compositor. Use whatever you need to know if the terminal emulator that runs
+senpai has focus):
 
 ```
 addr: irc.libera.chat
 nick: Guest123456
 user: senpai
 real: Guest von Lenon
-password: A secure password, I guess?
+passcmd: "gopass show irc/guest" # use your favorite CLI password solution here
 channels: ["#rahxephon"]
 highlights:
 	- guest
-- 
2.33.0