35d20ed050a5ce48a4390c1e3c5663e570c62cda
[mjo-overlay.git] / eclass / sys-user.eclass
1 # Copyright 1999-2017 Gentoo Foundation
2 # Distributed under the terms of the GNU General Public License v2
3
4 # @ECLASS: sys-user.eclass
5 # @MAINTAINER:
6 # Michael Orlitzky <mjo@gentoo.org>
7 # @BLURB: handle installation and removal of system users.
8 # @DESCRIPTION:
9 # This eclass does most of the work for the sys-user/ packages that
10 # supply system user accounts.
11
12 inherit user
13
14 EXPORT_FUNCTIONS pkg_pretend src_unpack src_configure src_compile src_install src_test pkg_preinst pkg_postinst pkg_prerm
15
16 : ${HOMEPAGE:="https://www.gentoo.org/"}
17 : ${DESCRIPTION:="The ${PN} system user"}
18 : ${LICENSE:="GPL-2"}
19
20 # If you want a different username, use a different package name. This
21 # prevents different people from claiming the same username.
22 SYS_USER_NAME="${PN}"
23
24 # @ECLASS-VARIABLE: SYS_USER_GROUPS
25 # @DESCRIPTION:
26 # A space-separated list of groups that the user will belong to.
27 # Dependencies on the appropriate sys-group packages are generated
28 # automatically.
29 : ${SYS_USER_GROUPS:=${PN}}
30
31 # @ECLASS-VARIABLE: SYS_USER_UID
32 # @REQUIRED
33 # @DESCRIPTION:
34 # etc.
35
36
37 # @ECLASS-VARIABLE: SYS_USER_UID_IMPORTANT
38 # @REQUIRED
39 # @DESCRIPTION:
40 # Set to "true" if you want to die() if you don't get your desired UID.
41 : ${SYS_USER_UID_IMPORTANT:=false}
42
43 # In many cases, if the UID of a user changes, packages depending on it
44 # will want to rebuild. We always use SLOT=0, because you can't install
45 # the same user twice. Then we use the UID as our subslot so that
46 # subslot deps can be used to rebuild packages when our UID changes.
47 SLOT="0/${SYS_USER_UID}"
48
49 # @ECLASS-VARIABLE: SYS_USER_HOME
50 # @DESCRIPTION:
51 # etc.
52 : ${SYS_USER_HOME:=/home/${SYS_USER_NAME}}
53
54 # @ECLASS-VARIABLE: SYS_USER_SHELL
55 # @DESCRIPTION:
56 # etc.
57 : ${SYS_USER_SHELL:=/bin/false}
58
59 case ${EAPI} in
60 6) ;;
61 *)
62 die "${ECLASS} is not compatible with EAPI=${EAPI}"
63 esac
64
65 # Depend on any groups we might need.
66 for _group in ${SYS_USER_GROUPS}; do
67 DEPEND+=" sys-group/${_group} "
68 RDEPEND+=" sys-group/${_group}:= "
69 done
70 unset _group
71
72 S="${WORKDIR}"
73
74 sys-user_src_unpack() { :; }
75 sys-user_src_compile() { :; }
76 sys-user_src_test() { :; }
77
78 sys-user_getuid() {
79 # Output the real UID of the given user, or the empty string if the
80 # user does not exist on the system.
81 echo $(id --real --user "${1}")
82 }
83
84 sys-user_create() {
85 # Create the user whose information is contained in the following
86 # variables:
87 #
88 # * SYS_USER_NAME
89 # * SYS_USER_UID
90 # * SYS_USER_SHELL
91 # * SYS_USER_HOME
92 # * SYS_USER_GROUPS
93 #
94 # We don't create a group with the same name; that should be the
95 # job of the matching sys-group package.
96 useradd --no-user-group \
97 ${SYS_USER_UID:+--uid }"${SYS_USER_UID}" \
98 ${SYS_USER_GROUPS:+--groups }"${SYS_USER_GROUPS}" \
99 --shell "${SYS_USER_SHELL}" \
100 --home-dir "${SYS_USER_HOME}" \
101 "${SYS_USER_NAME}"
102 }
103
104
105 sys-user_pkg_pretend() {
106 # Sanity checks that would otherwise run code in global scope.
107 #
108 # First ensure that the user didn't say his UID is important and
109 # then fail to specify one.
110 if [[ -z "${SYS_USER_UID}" ]] &&
111 [[ "${SYS_USER_UID_IMPORTANT}" == "true" ]]; then
112 # Don't make no damn sense.
113 die "arbitrary UID requested with SYS_USER_UID_IMPORTANT=true"
114 fi
115
116 # Next ensure that no other username owns an important UID.
117 if [[ "${SYS_USER_UID_IMPORTANT}" == "true" ]]; then
118 # Ok, the UID is important. Make sure nobody else has it. Or
119 # rather, nobody else *with a different username* has it.
120 local oldname=$(egetent passwd "${SYS_USER_UID}" | cut -f1 -d':')
121 if [[ "${SYS_USER_NAME}" != "${oldname}" ]]; then
122 die "important UID ${SYS_USER_UID} already belongs to ${oldname}"
123 fi
124 fi
125
126 # Finally, ensure that this username doesn't already exist with
127 # another UID if its UID is supposedly important.
128 local olduid=$(sys-user_getuid "${SYS_USER_NAME}")
129 if [[ -n "${olduid}" ]]; then
130 if [[ "${SYS_USER_UID_IMPORTANT}" == "true" ]] && \
131 [[ "${SYS_USER_UID}" != "${olduid}" ]]; then
132 # The UID is important and specified, but there is already a
133 # system user with this name and a different UID. Halp.
134 die "user ${SYS_USER_NAME} already exists with UID ${olduid}"
135 fi
136 fi
137 }
138
139 sys-user_src_configure() {
140 local current_uid=$(sys-user_getuid "${SYS_USER_NAME}")
141 if [[ -n "${current_uid}" ]]; then
142 # UPGRADE PATH: This user already exists, so if the eclass
143 # consumer doesn't care about some settings, we can reuse the
144 # pre-existing ones.
145 #
146 # This is also useful for sys-user package upgrades, because it
147 # prevents us from incrementing the UID on a reinstall, and doing
148 # so would break most packages that need a system user to exist.
149 if [[ "${SYS_USER_UID_IMPORTANT}" != "true" ]]; then
150 SYS_USER_UID="${current_uid}"
151 fi
152
153 if [[ -z "${SYS_USER_HOME}" ]]; then
154 SYS_USER_HOME=$(egethome "${SYS_USER_NAME}")
155 fi
156
157 if [[ -z "${SYS_USER_SHELL}" ]]; then
158 SYS_USER_SHELL=$(egetshell "${SYS_USER_NAME}")
159 fi
160 fi
161
162 # The "useradd" and "usermod" tools expect a comma-separated list,
163 # so change our spaces to commas. Having duplicates in the list is
164 # not a problem for those two tools.
165 SYS_USER_GROUPS="${SYS_USER_GROUPS// /,}"
166 }
167
168 sys-user_src_install() {
169 # Install a placeholder file to /var/lib/sys-user/$uid. This will
170 # cause collisions if two packages try to install users with the
171 # same UID. The same problem potentially exists with the username,
172 # but as long as SYS_USER_NAME is hard-coded to $PN, that shouldn't
173 # be possible.
174 #
175 # Beware, this only works if SYS_USER_UID is guaranteed to have a
176 # real UID and not, for example, -1. That is taken care of in
177 # src_configure() for now.
178 touch "${T}/${SYS_USER_UID}" || die
179 insinto "/var/lib/sys-user"
180 doins "${T}/${SYS_USER_UID}"
181 }
182
183 sys-user_pkg_preinst() {
184 if [[ -z $(sys-user_getuid "${SYS_USER_NAME}") ]]; then
185 # The user does not already exist. This is the nice and easy
186 # case because no matter how we got here, we want to go ahead
187 # and create the (new) user.
188 sys-user_create || die "failed to add user ${SYS_USER_NAME}"
189 elif [[ -n "${REPLACING_VERSIONS}" ]]; then
190 #
191 # This case is done in pkg_postint() to avoid clobbering a
192 # new user when we remove the old one.
193 #
194 :
195 else
196 # UPGRADE PATH: Ok, the user exists but this isn't an upgrade of
197 # a sys-user package. This is the upgrade path from the old
198 # style of user/group management to the new style. Lets see if
199 # the new user is compatible with the old one; it usually will be.
200 # We only bail out if there's a homedir or shell conflict.
201 #
202 # We should make it policy that new sys-user packages have the
203 # same homedir and shell as the existing ones created by
204 # ebuilds, but it can't hurt to check again here. These checks
205 # are done here (and not in pkg_pretend, where they would be
206 # more consistent) because the PMS states that REPLACING_VERSIONS
207 # may not be defined there.
208 #
209 # If a homedir/shell changes during a sys-user upgrade, we don't
210 # consider that a problem, because the change was knowingly made
211 # by a developer who just edited an ebuild to make that change.
212 local oldhome=$(egethome "${SYS_USER_NAME}")
213 local oldshell=$(egetshell "${SYS_USER_NAME}")
214
215 if [[ "${oldhome}" != "${SYS_USER_HOME}" ]]; then
216 die "home directory conflict for new user: ${SYS_USER_HOME}"
217 fi
218
219 if [[ "${oldhshell}" != "${SYS_USER_SHELL}" ]]; then
220 die "shell conflict for new user: ${SYS_USER_SHELL}"
221 fi
222
223 # The user already exists, so all we have left to do is to try
224 # to append SYS_USER_GROUPS to the existing groups.
225 usermod --append --groups "${SYS_USER_GROUPS}" \
226 || die "failed to append groups to existing user ${SYS_USER_NAME}"
227 fi
228 }
229
230 sys-user_pkg_postinst() {
231 if [[ -n "${REPLACING_VERSIONS}" ]]; then
232 # This is an upgrade from a previous version of a sys-user
233 # package. This case has to be handled carefully to make sure
234 # that the pkg_prerm() of the old version doesn't remove the user
235 # that this new version is going to add. At this point, in our
236 # pkg_postinst(), the old version's pkg_prerm() phase should have
237 # already happened.
238 if [[ -n $(sys-user_getuid "${SYS_USER_NAME}") ]]; then
239 die "User ${SYS_USER_NAME} already exists during an upgrade."
240 else
241 sys-user_create || die "failed to add user ${SYS_USER_NAME}"
242 fi
243 fi
244 }
245
246 sys-user_pkg_prerm() {
247 if [[ -z $(sys-user_getuid "${SYS_USER_NAME}") ]]; then
248 # We have successfully done nothing.
249 ewarn "Tried to remove nonexistent user ${SYS_USER_NAME}."
250 else
251 userdel "${SYS_USER_NAME}" || \
252 die "failed to remove user ${SYS_USER_NAME}"
253 einfo "Removed user ${SYS_USER_NAME} from the system."
254 fi
255 }