external/bsd/kyua-cli/dist/utils/passwd.cpp

   1 // Copyright 2010 Google Inc.
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  28
  29 #include "utils/passwd.hpp"
  30
  31 extern "C" {
  32 #include <sys/types.h>
  33
  34 #include <pwd.h>
  35 #include <unistd.h>
  36 }
  37
  38 #include <stdexcept>
  39
  40 #include "utils/format/macros.hpp"
  41 #include "utils/logging/macros.hpp"
  42 #include "utils/optional.ipp"
  43 #include "utils/sanity.hpp"
  44
  45 namespace passwd_ns = utils::passwd;
  46
  47
  48 namespace {
  49
  50
  51 /// If defined, replaces the value returned by current_user().
  52 static utils::optional< passwd_ns::user > fake_current_user;
  53
  54
  55 /// If not empty, defines the current set of mock users.
  56 static std::vector< passwd_ns::user > mock_users;
  57
  58
  59 /// Formats a user for logging purposes.
  60 ///
  61 /// \param user The user to format.
  62 ///
  63 /// \return The user as a string.
  64 static std::string
  65 format_user(const passwd_ns::user& user)
  66 {
  67     return F("name=%s, uid=%s, gid=%s") % user.name % user.uid % user.gid;
  68 }
  69
  70
  71 }  // anonymous namespace
  72
  73
  74 /// Constructs a new user.
  75 ///
  76 /// \param name_ The name of the user.
  77 /// \param uid_ The user identifier.
  78 /// \param gid_ The login group identifier.
  79 passwd_ns::user::user(const std::string& name_, const unsigned int uid_,
  80                       const unsigned int gid_) :
  81     name(name_),
  82     uid(uid_),
  83     gid(gid_)
  84 {
  85 }
  86
  87
  88 /// Checks if the user has superpowers or not.
  89 ///
  90 /// \return True if the user is root, false otherwise.
  91 bool
  92 passwd_ns::user::is_root(void) const
  93 {
  94     return uid == 0;
  95 }
  96
  97
  98 /// Gets the current user.
  99 ///
 100 /// \return The current user.
 101 passwd_ns::user
 102 passwd_ns::current_user(void)
 103 {
 104     if (fake_current_user) {
 105         const user u = fake_current_user.get();
 106         LD(F("Current user is fake: %s") % format_user(u));
 107         return u;
 108     } else {
 109         const user u = find_user_by_uid(::getuid());
 110         LD(F("Current user is: %s") % format_user(u));
 111         return u;
 112     }
 113 }
 114
 115
 116 /// Gets information about a user by its name.
 117 ///
 118 /// \param name The name of the user to query.
 119 ///
 120 /// \return The information about the user.
 121 ///
 122 /// \throw std::runtime_error If the user does not exist.
 123 passwd_ns::user
 124 passwd_ns::find_user_by_name(const std::string& name)
 125 {
 126     if (mock_users.empty()) {
 127         const struct ::passwd* pw = ::getpwnam(name.c_str());
 128         if (pw == NULL)
 129             throw std::runtime_error(F("Failed to get information about the "
 130                                        "user '%s'") % name);
 131         INV(pw->pw_name == name);
 132         return user(pw->pw_name, pw->pw_uid, pw->pw_gid);
 133     } else {
 134         for (std::vector< user >::const_iterator iter = mock_users.begin();
 135              iter != mock_users.end(); iter++) {
 136             if ((*iter).name == name)
 137                 return *iter;
 138         }
 139         throw std::runtime_error(F("Failed to get information about the "
 140                                    "user '%s'") % name);
 141     }
 142 }
 143
 144
 145 /// Gets information about a user by its identifier.
 146 ///
 147 /// \param uid The identifier of the user to query.
 148 ///
 149 /// \return The information about the user.
 150 ///
 151 /// \throw std::runtime_error If the user does not exist.
 152 passwd_ns::user
 153 passwd_ns::find_user_by_uid(const unsigned int uid)
 154 {
 155     if (mock_users.empty()) {
 156         const struct ::passwd* pw = ::getpwuid(uid);
 157         if (pw == NULL)
 158             throw std::runtime_error(F("Failed to get information about the "
 159                                        "user with UID %s") % uid);
 160         INV(pw->pw_uid == uid);
 161         return user(pw->pw_name, pw->pw_uid, pw->pw_gid);
 162     } else {
 163         for (std::vector< user >::const_iterator iter = mock_users.begin();
 164              iter != mock_users.end(); iter++) {
 165             if ((*iter).uid == uid)
 166                 return *iter;
 167         }
 168         throw std::runtime_error(F("Failed to get information about the "
 169                                    "user with UID %s") % uid);
 170     }
 171 }
 172
 173
 174 /// Overrides the current user for testing purposes.
 175 ///
 176 /// This DOES NOT change the current privileges!
 177 ///
 178 /// \param new_current_user The new current user.
 179 void
 180 passwd_ns::set_current_user_for_testing(const user& new_current_user)
 181 {
 182     fake_current_user = new_current_user;
 183 }
 184
 185
 186 /// Overrides the current set of users for testing purposes.
 187 ///
 188 /// \param users The new users set.  Cannot be empty.
 189 void
 190 passwd_ns::set_mock_users_for_testing(const std::vector< user >& users)
 191 {
 192     PRE(!users.empty());
 193     mock_users = users;
 194 }