python模块介绍-pwd：密码数据库
pwd
pwd简介
| 平台 | *inux |
pwd可以访问Unix用户帐户和密码数据库。
密码数据库项由结构体passwd(类似元组)表示，参见pwd.h：
| 属性 | 含义 |
| pw_name | Login name |
| pw_passwd | Optional encrypted password |
| pw_uid | Numerical user ID |
| pw_gid | Numerical group ID |
| pw_gecos | User name or comment field |
| pw_dir | User home directory |
| pw_shell | User command interpreter |
除了pw_uid和pw_gid是整数外，其他都是字符串。
pwd方法
| pwd.getpwuid(uid) | Return the password database entry for the given numeric user ID. |
| pwd.getpwnam(name) | Return the password database entry for the given user name. |
| pwd.getpwall() | Return a list of all available password database entries, in arbitrary order. |
简单示例：
In [4]: import pwd
In [5]: pwd.getpwuid(os.getuid())
Out[5]: pwd.struct_passwd(pw_name='root', pw_passwd='x', pw_uid=0, pw_gid=0, pw_gecos='root', pw_dir='/root', pw_shell='/bin/bash')
In [6]: pwd.getpwnam('root')
Out[6]: pwd.struct_passwd(pw_name='root', pw_passwd='x', pw_uid=0, pw_gid=0, pw_gecos='root', pw_dir='/root', pw_shell='/bin/bash')
In [7]: pwd.getpwall()
Out[7]:
[pwd.struct_passwd(pw_name='root', pw_passwd='x', pw_uid=0, pw_gid=0, pw_gecos='root', pw_dir='/root', pw_shell='/bin/bash'),
pwd.struct_passwd(pw_name='adm', pw_passwd='x', pw_uid=3, pw_gid=4, pw_gecos='adm', pw_dir='/var/adm', pw_shell='/sbin/nologin'),
...
pwd.struct_passwd(pw_name='dockerroot', pw_passwd='x', pw_uid=992, pw_gid=986, pw_gecos='Docker User', pw_dir='/var/lib/docker', pw_shell='/sbin/nologin')]
这种方式通常已经看不到密码，因为密码大多存在/etc/shadows，建议使用spwd。
spwd
spwd简介
| 平台 | *inux |
| 版本 | 2.5以上 |
spwd可以访问Unix shadow密码数据库。通常需要root权限。
密码数据库项由结构体spwd(类似元组)表示，参见shadow.h：
| 属性 | 含义 |
| sp_pwd | Encrypted password |
| sp_lstchg | Date of last change |
| sp_min | Minimal number of days between changes |
| sp_max | Maximum number of days between changes |
| sp_warn | Number of days before password expires to warn user about it |
| sp_inact | Number of days after password expires until account is blocked |
| sp_expire | Number of days since 1970-01-01 until account is disabled |
| sp_flag | Reserved |
除了sp_nam和sp_pwd是字符串外，其他都是整数。
spwd方法
| spwd.getspnam(name) | Return the shadow password database entry for the given user name. |
| spwd.getspall() | Return a list of all available shadow password database entries, in arbitrary order. |
简单示例：
In [1]: import spwd
In [2]: spwd.getspnam('root')
Out[2]: spwd.struct_spwd(sp_nam='root', sp_pwd='$6$heqCVK0U$MDsVT5qoyhgFnE2vlzK4geQzjS/nEVuQfQslhsYX.prJUpqP8SlZbFF6vOZjdgzpnA2YgOx/Hc461mHFSOaLm0', sp_lstchg=16548, sp_min=0, sp_max=99999, sp_warn=7, sp_inact=-1, sp_expire=-1, sp_flag=-1)
In [3]: spwd.getspall()
Out[3]:
[spwd.struct_spwd(sp_nam='root', sp_pwd='$6$heqCVK0U$MDsVT5qoyhgFnE2vlzK4geQzjS/nEVuQfQslhsYX.prJUpqP8SlZbFF6vOZjdgzpnA2YgOx/Hc461mHFSOaLm0', sp_lstchg=16548, sp_min=0, sp_max=99999, sp_warn=7, sp_inact=-1, sp_expire=-1, sp_flag=-1),
...
spwd.struct_spwd(sp_nam='dockerroot', sp_pwd='!!', sp_lstchg=16555, sp_min=-1, sp_max=-1, sp_warn=-1, sp_inact=-1, sp_expire=-1, sp_flag=-1)]
grp
grp简介
| 平台 | *inux |
spwd可以访问Unix组数据库。
密码数据库项由结构体group(类似元组)表示，参见pwd.h：
| 属性 | 含义 | 类型 |
| gr_name | the name of the group | 字符串 |
| gr_passwd | the (encrypted) group password; often empty | 字符串 |
| gr_gid | the numerical group ID | integer |
| gr_mem | all the group member’s user names | 字符串列表 |
注意gr_mem可能不完整
pwd方法
| grp.getgrgid(gid) | Return the group database entry for the given numeric group ID. KeyError is raised if the entry asked for cannot be found. |
| grp.getgrnam(name) | Return the group database entry for the given group name. KeyError is raised if the entry asked for cannot be found. |
| grp.getgrall() | Return a list of all available group entries, in arbitrary order. |
简单示例：
In [1]: import grp
In [2]: grp.getgrgid(72)
Out[2]: grp.struct_group(gr_name='tcpdump', gr_passwd='x', gr_gid=72, gr_mem=[])
In [3]: grp.getgrnam('tmux')
Out[3]: grp.struct_group(gr_name='tmux', gr_passwd='x', gr_gid=1009, gr_mem=['tmux', 'test'])
In [4]: grp.getgrall()
Out[4]:
[grp.struct_group(gr_name='root', gr_passwd='x', gr_gid=0, gr_mem=[]),
...
grp.struct_group(gr_name='dockerroot', gr_passwd='x', gr_gid=986, gr_mem=[])]
注意一些用户没有在/etc/group中注明所属组，另外以+或-开头的组名可能也不适用。
参考资料
python2 pwd 英文文档
作者博客：http://my.oschina.net/u/1433482
python2 spwd英文文档
python2 grp英文文档