From 88d2ec272d3e503412e477d9abaebfe2ca199e78 Mon Sep 17 00:00:00 2001

From: Filipe Brandenburger <filbranden@google.com>

Date: Sun, 6 Sep 2015 23:06:53 -0700

Subject: [PATCH] execute: Add new PassEnvironment= directive

This directive allows passing environment variables from the system

manager to spawned services. Variables in the system manager can be set

inside a container by passing `--set-env=...` options to systemd-spawn.

Tested with an on-disk test.service unit. Tested using multiple variable

names on a single line, with an empty setting to clear the current list

of variables, with non-existing variables.

Tested using `systemd-run -p PassEnvironment=VARNAME` to confirm it

works with transient units.

Confirmed that `systemctl show` will display the PassEnvironment

settings.

Checked that man pages are generated correctly.

No regressions in `make check`.

(cherry picked from commit b4c14404b3e8753c41bac0b1d49369230a15c544)

Resolves: #1426214

---

 man/systemd.exec.xml                  | 27 +++++++++++++++

 shell-completion/bash/systemd-run     |  2 +-

 src/core/dbus-execute.c               | 34 ++++++++++++++++++

 src/core/execute.c                    | 44 ++++++++++++++++++++++--

 src/core/execute.h                    |  1 +

 src/core/load-fragment-gperf.gperf.m4 |  1 +

 src/core/load-fragment.c              | 65 +++++++++++++++++++++++++++++++++++

 src/core/load-fragment.h              |  1 +

 src/libsystemd/sd-bus/bus-util.c      |  2 +-

 src/shared/env-util.c                 | 15 ++++++++

 src/shared/env-util.h                 |  1 +

 11 files changed, 189 insertions(+), 4 deletions(-)

diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml

index c5199d3..aa5831c 100644

--- a/man/systemd.exec.xml

+++ b/man/systemd.exec.xml

@@ -294,6 +294,33 @@

       </varlistentry>

       <varlistentry>

+        <term><varname>PassEnvironment=</varname></term>

+

+        <listitem><para>Pass environment variables from the systemd system

+        manager to executed processes. Takes a space-separated list of variable

+        names. This option may be specified more than once, in which case all

+        listed variables will be set. If the empty string is assigned to this

+        option, the list of environment variables is reset, all prior

+        assignments have no effect. Variables that are not set in the system

+        manager will not be passed and will be silently ignored.</para>

+

+        <para>Variables passed from this setting are overridden by those passed

+        from <varname>Environment=</varname> or

+        <varname>EnvironmentFile=</varname>.</para>

+

+        <para>Example:

+        <programlisting>PassEnvironment=VAR1 VAR2 VAR3</programlisting>

+        passes three variables <literal>VAR1</literal>,

+        <literal>VAR2</literal>, <literal>VAR3</literal>

+        with the values set for those variables in PID1.</para>

+

+        <para>

+        See

+        <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>

+        for details about environment variables.</para></listitem>

+      </varlistentry>

+

+      <varlistentry>

         <term><varname>StandardInput=</varname></term>

         <listitem><para>Controls where file descriptor 0 (STDIN) of

         the executed processes is connected to. Takes one of

diff --git a/shell-completion/bash/systemd-run b/shell-completion/bash/systemd-run

index 5145cd3..36ffa46 100644

--- a/shell-completion/bash/systemd-run

+++ b/shell-completion/bash/systemd-run

@@ -73,7 +73,7 @@ _systemd_run() {

                          KillSignal= LimitCPU= LimitFSIZE= LimitDATA= LimitSTACK=

                          LimitCORE= LimitRSS= LimitNOFILE= LimitAS= LimitNPROC=

                          LimitMEMLOCK= LimitLOCKS= LimitSIGPENDING= LimitMSGQUEUE=

-                         LimitNICE= LimitRTPRIO= LimitRTTIME='

+                         LimitNICE= LimitRTPRIO= LimitRTTIME= PassEnvironment='

             COMPREPLY=( $(compgen -W '$comps' -- "$cur") )

             return 0

diff --git a/src/core/dbus-execute.c b/src/core/dbus-execute.c

index a9f7971..da8b10d 100644

--- a/src/core/dbus-execute.c

+++ b/src/core/dbus-execute.c

@@ -597,6 +597,7 @@ const sd_bus_vtable bus_exec_vtable[] = {

         SD_BUS_VTABLE_START(0),

         SD_BUS_PROPERTY("Environment", "as", NULL, offsetof(ExecContext, environment), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("EnvironmentFiles", "a(sb)", property_get_environment_files, 0, SD_BUS_VTABLE_PROPERTY_CONST),

+        SD_BUS_PROPERTY("PassEnvironment", "as", NULL, offsetof(ExecContext, pass_environment), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("UMask", "u", bus_property_get_mode, offsetof(ExecContext, umask), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("LimitCPU", "t", property_get_rlimit, offsetof(ExecContext, rlimit[RLIMIT_CPU]), SD_BUS_VTABLE_PROPERTY_CONST),

         SD_BUS_PROPERTY("LimitFSIZE", "t", property_get_rlimit, offsetof(ExecContext, rlimit[RLIMIT_FSIZE]), SD_BUS_VTABLE_PROPERTY_CONST),

@@ -963,6 +964,39 @@ int bus_exec_context_set_transient_property(

                 return 1;

+        } else if (streq(name, "PassEnvironment")) {

+

+                _cleanup_strv_free_ char **l = NULL;

+

+                r = sd_bus_message_read_strv(message, &l);

+                if (r < 0)

+                        return r;

+

+                if (!strv_env_name_is_valid(l))

+                        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid PassEnvironment block.");

+

+                if (mode != UNIT_CHECK) {

+                        if (strv_isempty(l)) {

+                                strv_free(c->pass_environment);

+                                c->pass_environment = NULL;

+                                unit_write_drop_in_private_format(u, mode, name, "PassEnvironment=\n");

+                        } else {

+                                _cleanup_free_ char *joined = NULL;

+

+                                r = strv_extend_strv(&c->pass_environment, l);

+                                if (r < 0)

+                                        return r;

+

+                                joined = strv_join_quoted(c->pass_environment);

+                                if (!joined)

+                                        return -ENOMEM;

+

+                                unit_write_drop_in_private_format(u, mode, name, "PassEnvironment=%s\n", joined);

+                        }

+                }

+

+                return 1;

+

         } else if (rlimit_from_string(name) >= 0) {

                 uint64_t rl;

                 rlim_t x;

diff --git a/src/core/execute.c b/src/core/execute.c

index 863babd..f72b209 100644

--- a/src/core/execute.c

+++ b/src/core/execute.c

@@ -1256,6 +1256,34 @@ static int build_environment(

         return 0;

 }

+static int build_pass_environment(const ExecContext *c, char ***ret) {

+        _cleanup_strv_free_ char **pass_env = NULL;

+        size_t n_env = 0, n_bufsize = 0;

+        char **i;

+

+        STRV_FOREACH(i, c->pass_environment) {

+                _cleanup_free_ char *x = NULL;

+                char *v;

+

+                v = getenv(*i);

+                if (!v)

+                        continue;

+                x = strjoin(*i, "=", v, NULL);

+                if (!x)

+                        return -ENOMEM;

+                if (!GREEDY_REALLOC(pass_env, n_bufsize, n_env + 2))

+                        return -ENOMEM;

+                pass_env[n_env++] = x;

+                pass_env[n_env] = NULL;

+                x = NULL;

+        }

+

+        *ret = pass_env;

+        pass_env = NULL;

+

+        return 0;

+}

+

 static bool exec_needs_mount_namespace(

                 const ExecContext *context,

                 const ExecParameters *params,

@@ -1297,7 +1325,7 @@ static int exec_child(

                 char **files_env,

                 int *exit_status) {

-        _cleanup_strv_free_ char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;

+        _cleanup_strv_free_ char **our_env = NULL, **pass_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;

         _cleanup_free_ char *mac_selinux_context_net = NULL;

         const char *username = NULL, *home = NULL, *shell = NULL;

         unsigned n_dont_close = 0;

@@ -1805,9 +1833,16 @@ static int exec_child(

                 return r;

         }

-        final_env = strv_env_merge(5,

+        r = build_pass_environment(context, &pass_env);

+        if (r < 0) {

+                *exit_status = EXIT_MEMORY;

+                return r;

+        }

+

+        final_env = strv_env_merge(6,

                                    params->environment,

                                    our_env,

+                                   pass_env,

                                    context->environment,

                                    files_env,

                                    pam_env,

@@ -1965,6 +2000,8 @@ void exec_context_done(ExecContext *c) {

         strv_free(c->environment_files);

         c->environment_files = NULL;

+        strv_free(c->pass_environment);

+        c->pass_environment = NULL;

         for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {

                 free(c->rlimit[l]);

@@ -2267,6 +2304,9 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {

         STRV_FOREACH(e, c->environment_files)

                 fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e);

+        STRV_FOREACH(e, c->pass_environment)

+                fprintf(f, "%sPassEnvironment: %s\n", prefix, *e);

+

         if (c->nice_set)

                 fprintf(f,

                         "%sNice: %i\n",

diff --git a/src/core/execute.h b/src/core/execute.h

index 6e0c9fa..cadd0e6 100644

--- a/src/core/execute.h

+++ b/src/core/execute.h

@@ -96,6 +96,7 @@ struct ExecRuntime {

 struct ExecContext {

         char **environment;

         char **environment_files;

+        char **pass_environment;

         struct rlimit *rlimit[_RLIMIT_MAX];

         char *working_directory, *root_directory;

diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4

index c866a9c..b50fe45 100644

--- a/src/core/load-fragment-gperf.gperf.m4

+++ b/src/core/load-fragment-gperf.gperf.m4

@@ -33,6 +33,7 @@ $1.CPUAffinity,                  config_parse_exec_cpu_affinity,     0,

 $1.UMask,                        config_parse_mode,                  0,                             offsetof($1, exec_context.umask)

 $1.Environment,                  config_parse_environ,               0,                             offsetof($1, exec_context.environment)

 $1.EnvironmentFile,              config_parse_unit_env_file,         0,                             offsetof($1, exec_context.environment_files)

+$1.PassEnvironment,              config_parse_pass_environ,          0,                             offsetof($1, exec_context.pass_environment)

 $1.StandardInput,                config_parse_input,                 0,                             offsetof($1, exec_context.std_input)

 $1.StandardOutput,               config_parse_output,                0,                             offsetof($1, exec_context.std_output)

 $1.StandardError,                config_parse_output,                0,                             offsetof($1, exec_context.std_error)

diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c

index 3a3c456..c450fe2 100644

--- a/src/core/load-fragment.c

+++ b/src/core/load-fragment.c

@@ -2265,6 +2265,71 @@ int config_parse_environ(const char *unit,

         return 0;

 }

+int config_parse_pass_environ(const char *unit,

+                              const char *filename,

+                              unsigned line,

+                              const char *section,

+                              unsigned section_line,

+                              const char *lvalue,

+                              int ltype,

+                              const char *rvalue,

+                              void *data,

+                              void *userdata) {

+

+        const char *whole_rvalue = rvalue;

+        char*** passenv = data;

+        _cleanup_strv_free_ char **n = NULL;

+        size_t nlen = 0, nbufsize = 0;

+        int r;

+

+        assert(filename);

+        assert(lvalue);

+        assert(rvalue);

+        assert(data);

+

+        if (isempty(rvalue)) {

+                /* Empty assignment resets the list */

+                strv_free(*passenv);

+                *passenv = NULL;

+                return 0;

+        }

+

+        for (;;) {

+                _cleanup_free_ char *word = NULL;

+

+                r = extract_first_word(&rvalue, &word, WHITESPACE, EXTRACT_QUOTES);

+                if (r == 0)

+                        break;

+                if (r == -ENOMEM)

+                        return log_oom();

+                if (r < 0) {

+                        log_syntax(unit, LOG_ERR, filename, line, r,

+                                   "Trailing garbage in %s, ignoring: %s", lvalue, whole_rvalue);

+                        break;

+                }

+

+                if (!env_name_is_valid(word)) {

+                        log_syntax(unit, LOG_ERR, filename, line, EINVAL,

+                                   "Invalid environment name for %s, ignoring: %s", lvalue, word);

+                        continue;

+                }

+

+                if (!GREEDY_REALLOC(n, nbufsize, nlen + 2))

+                        return log_oom();

+                n[nlen++] = word;

+                n[nlen] = NULL;

+                word = NULL;

+        }

+

+        if (n) {

+                r = strv_extend_strv(passenv, n);

+                if (r < 0)

+                        return r;

+        }

+

+        return 0;

+}

+

 int config_parse_ip_tos(const char *unit,

                         const char *filename,

                         unsigned line,

diff --git a/src/core/load-fragment.h b/src/core/load-fragment.h

index 7c69e53..9dd7d1b 100644

--- a/src/core/load-fragment.h

+++ b/src/core/load-fragment.h

@@ -85,6 +85,7 @@ int config_parse_syscall_filter(const char *unit, const char *filename, unsigned

 int config_parse_syscall_archs(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

 int config_parse_syscall_errno(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

 int config_parse_environ(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

+int config_parse_pass_environ(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

 int config_parse_unit_slice(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

 int config_parse_cpu_shares(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

 int config_parse_memory_limit(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

diff --git a/src/libsystemd/sd-bus/bus-util.c b/src/libsystemd/sd-bus/bus-util.c

index d357760..ed0849b 100644

--- a/src/libsystemd/sd-bus/bus-util.c

+++ b/src/libsystemd/sd-bus/bus-util.c

@@ -1535,7 +1535,7 @@ int bus_append_unit_property_assignment(sd_bus_message *m, const char *assignmen

                 r = sd_bus_message_append(m, "v", "i", i);

-        } else if (streq(field, "Environment")) {

+        } else if (STR_IN_SET(field, "Environment", "PassEnvironment")) {

                 r = sd_bus_message_append(m, "v", "as", 1, eq);

diff --git a/src/shared/env-util.c b/src/shared/env-util.c

index e8da4c9..581d84a 100644

--- a/src/shared/env-util.c

+++ b/src/shared/env-util.c

@@ -136,6 +136,21 @@ bool strv_env_is_valid(char **e) {

         return true;

 }

+bool strv_env_name_is_valid(char **l) {

+        char **p, **q;

+

+        STRV_FOREACH(p, l) {

+                if (!env_name_is_valid(*p))

+                        return false;

+

+                STRV_FOREACH(q, p + 1)

+                        if (streq(*p, *q))

+                                return false;

+        }

+

+        return true;

+}

+

 bool strv_env_name_or_assignment_is_valid(char **l) {

         char **p, **q;

diff --git a/src/shared/env-util.h b/src/shared/env-util.h

index 252d87b..b8c2d81 100644

--- a/src/shared/env-util.h

+++ b/src/shared/env-util.h

@@ -34,6 +34,7 @@ bool strv_env_is_valid(char **e);

 #define strv_env_clean(l) strv_env_clean_with_callback(l, NULL, NULL)

 char **strv_env_clean_with_callback(char **l, void (*invalid_callback)(const char *p, void *userdata), void *userdata);

+bool strv_env_name_is_valid(char **l);

 bool strv_env_name_or_assignment_is_valid(char **l);

 char **strv_env_merge(unsigned n_lists, ...);