From 47b5a55239fe21e24d47ce56e752a0ee328b697f Mon Sep 17 00:00:00 2001 From: Günther Deschner Date: Wed, 3 Jun 2009 11:10:13 +0200 Subject: nss_wrapper: add struct nwrap_backend. Guenther --- lib/nss_wrapper/nss_wrapper.c | 405 +++++++++++++++++++++++++++++++++--------- 1 file changed, 320 insertions(+), 85 deletions(-) diff --git a/lib/nss_wrapper/nss_wrapper.c b/lib/nss_wrapper/nss_wrapper.c index 317c251a24..cffa04401f 100644 --- a/lib/nss_wrapper/nss_wrapper.c +++ b/lib/nss_wrapper/nss_wrapper.c @@ -139,59 +139,87 @@ #define NWRAP_VERBOSE(args) #endif -struct nwrap_ops { +struct nwrap_backend { const char *name; - struct passwd * (*nw_getpwnam)(const char *name); - int (*nw_getpwnam_r)(const char *name, struct passwd *pwdst, - char *buf, size_t buflen, struct passwd **pwdstp); - struct passwd * (*nw_getpwuid)(uid_t uid); - int (*nw_getpwuid_r)(uid_t uid, struct passwd *pwdst, - char *buf, size_t buflen, struct passwd **pwdstp); - void (*nw_setpwent)(void); - struct passwd * (*nw_getpwent)(void); - int (*nw_getpwent_r)(struct passwd *pwdst, char *buf, - size_t buflen, struct passwd **pwdstp); - void (*nw_endpwent)(void); - int (*nw_initgroups)(const char *user, gid_t group); - struct group * (*nw_getgrnam)(const char *name); - int (*nw_getgrnam_r)(const char *name, struct group *grdst, - char *buf, size_t buflen, struct group **grdstp); - struct group * (*nw_getgrgid)(gid_t gid); - int (*nw_getgrgid_r)(gid_t gid, struct group *grdst, - char *buf, size_t buflen, struct group **grdstp); - void (*nw_setgrent)(void); - struct group * (*nw_getgrent)(void); - int (*nw_getgrent_r)(struct group *grdst, char *buf, - size_t buflen, struct group **grdstp); - void (*nw_endgrent)(void); + struct nwrap_ops *ops; }; -static struct passwd *nwrap_files_getpwnam(const char *name); -static int nwrap_files_getpwnam_r(const char *name, struct passwd *pwdst, +struct nwrap_ops { + struct passwd * (*nw_getpwnam)(struct nwrap_backend *b, + const char *name); + int (*nw_getpwnam_r)(struct nwrap_backend *b, + const char *name, struct passwd *pwdst, + char *buf, size_t buflen, struct passwd **pwdstp); + struct passwd * (*nw_getpwuid)(struct nwrap_backend *b, + uid_t uid); + int (*nw_getpwuid_r)(struct nwrap_backend *b, + uid_t uid, struct passwd *pwdst, + char *buf, size_t buflen, struct passwd **pwdstp); + void (*nw_setpwent)(struct nwrap_backend *b); + struct passwd * (*nw_getpwent)(struct nwrap_backend *b); + int (*nw_getpwent_r)(struct nwrap_backend *b, + struct passwd *pwdst, char *buf, + size_t buflen, struct passwd **pwdstp); + void (*nw_endpwent)(struct nwrap_backend *b); + int (*nw_initgroups)(struct nwrap_backend *b, + const char *user, gid_t group); + struct group * (*nw_getgrnam)(struct nwrap_backend *b, + const char *name); + int (*nw_getgrnam_r)(struct nwrap_backend *b, + const char *name, struct group *grdst, + char *buf, size_t buflen, struct group **grdstp); + struct group * (*nw_getgrgid)(struct nwrap_backend *b, + gid_t gid); + int (*nw_getgrgid_r)(struct nwrap_backend *b, + gid_t gid, struct group *grdst, + char *buf, size_t buflen, struct group **grdstp); + void (*nw_setgrent)(struct nwrap_backend *b); + struct group * (*nw_getgrent)(struct nwrap_backend *b); + int (*nw_getgrent_r)(struct nwrap_backend *b, + struct group *grdst, char *buf, + size_t buflen, struct group **grdstp); + void (*nw_endgrent)(struct nwrap_backend *b); +}; + +/* protoypes for files backend */ + + +static struct passwd *nwrap_files_getpwnam(struct nwrap_backend *b, + const char *name); +static int nwrap_files_getpwnam_r(struct nwrap_backend *b, + const char *name, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp); -static struct passwd *nwrap_files_getpwuid(uid_t uid); -static int nwrap_files_getpwuid_r(uid_t uid, struct passwd *pwdst, +static struct passwd *nwrap_files_getpwuid(struct nwrap_backend *b, + uid_t uid); +static int nwrap_files_getpwuid_r(struct nwrap_backend *b, + uid_t uid, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp); -static void nwrap_files_setpwent(void); -static struct passwd *nwrap_files_getpwent(void); -static int nwrap_files_getpwent_r(struct passwd *pwdst, char *buf, +static void nwrap_files_setpwent(struct nwrap_backend *b); +static struct passwd *nwrap_files_getpwent(struct nwrap_backend *b); +static int nwrap_files_getpwent_r(struct nwrap_backend *b, + struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp); -static void nwrap_files_endpwent(void); -static int nwrap_files_initgroups(const char *user, gid_t group); -static struct group *nwrap_files_getgrnam(const char *name); -static int nwrap_files_getgrnam_r(const char *name, struct group *grdst, +static void nwrap_files_endpwent(struct nwrap_backend *b); +static int nwrap_files_initgroups(struct nwrap_backend *b, + const char *user, gid_t group); +static struct group *nwrap_files_getgrnam(struct nwrap_backend *b, + const char *name); +static int nwrap_files_getgrnam_r(struct nwrap_backend *b, + const char *name, struct group *grdst, char *buf, size_t buflen, struct group **grdstp); -static struct group *nwrap_files_getgrgid(gid_t gid); -static int nwrap_files_getgrgid_r(gid_t gid, struct group *grdst, +static struct group *nwrap_files_getgrgid(struct nwrap_backend *b, + gid_t gid); +static int nwrap_files_getgrgid_r(struct nwrap_backend *b, + gid_t gid, struct group *grdst, char *buf, size_t buflen, struct group **grdstp); -static void nwrap_files_setgrent(void); -static struct group *nwrap_files_getgrent(void); -static int nwrap_files_getgrent_r(struct group *grdst, char *buf, +static void nwrap_files_setgrent(struct nwrap_backend *b); +static struct group *nwrap_files_getgrent(struct nwrap_backend *b); +static int nwrap_files_getgrent_r(struct nwrap_backend *b, + struct group *grdst, char *buf, size_t buflen, struct group **grdstp); -static void nwrap_files_endgrent(void); +static void nwrap_files_endgrent(struct nwrap_backend *b); struct nwrap_ops nwrap_files_ops = { - .name = "files", .nw_getpwnam = nwrap_files_getpwnam, .nw_getpwnam_r = nwrap_files_getpwnam_r, .nw_getpwuid = nwrap_files_getpwuid, @@ -212,7 +240,9 @@ struct nwrap_ops nwrap_files_ops = { }; struct nwrap_main { - struct nwrap_ops *ops; + const char *nwrap_switch; + int num_backends; + struct nwrap_backend *backends; }; struct nwrap_main *nwrap_main_global; @@ -256,6 +286,40 @@ struct nwrap_gr nwrap_gr_global; static bool nwrap_gr_parse_line(struct nwrap_cache *nwrap, char *line); static void nwrap_gr_unload(struct nwrap_cache *nwrap); +static bool nwrap_module_init(const char *name, + struct nwrap_ops *ops, + int *num_backends, + struct nwrap_backend **backends) +{ + *backends = (struct nwrap_backend *)realloc(*backends, + sizeof(struct nwrap_backend) * ((*num_backends) + 1)); + if (!*backends) { + NWRAP_ERROR(("%s: out of memory\n", + __location__)); + } + + (*backends)[*num_backends].name = name; + (*backends)[*num_backends].ops = ops; + + (*num_backends)++; + + return true; +} + +static void nwrap_backend_init(struct nwrap_main *r) +{ + r->num_backends = 0; + r->backends = NULL; + + if (!nwrap_module_init("files", &nwrap_files_ops, + &r->num_backends, + &r->backends)) { + NWRAP_ERROR(("%s: failed to initialize 'files' backend\n", + __location__)); + return; + } +} + static void nwrap_init(void) { static bool initialized; @@ -265,7 +329,7 @@ static void nwrap_init(void) nwrap_main_global = &__nwrap_main_global; - nwrap_main_global->ops = &nwrap_files_ops; + nwrap_backend_init(nwrap_main_global); nwrap_pw_global.cache = &__nwrap_cache_pw; @@ -865,8 +929,8 @@ static int nwrap_gr_copy_r(const struct group *src, struct group *dst, } /* user functions */ - -static struct passwd *nwrap_files_getpwnam(const char *name) +static struct passwd *nwrap_files_getpwnam(struct nwrap_backend *b, + const char *name) { int i; @@ -889,12 +953,13 @@ static struct passwd *nwrap_files_getpwnam(const char *name) return NULL; } -static int nwrap_files_getpwnam_r(const char *name, struct passwd *pwdst, +static int nwrap_files_getpwnam_r(struct nwrap_backend *b, + const char *name, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { struct passwd *pw; - pw = nwrap_files_getpwnam(name); + pw = nwrap_files_getpwnam(b, name); if (!pw) { if (errno == 0) { return ENOENT; @@ -905,7 +970,8 @@ static int nwrap_files_getpwnam_r(const char *name, struct passwd *pwdst, return nwrap_pw_copy_r(pw, pwdst, buf, buflen, pwdstp); } -static struct passwd *nwrap_files_getpwuid(uid_t uid) +static struct passwd *nwrap_files_getpwuid(struct nwrap_backend *b, + uid_t uid) { int i; @@ -928,12 +994,13 @@ static struct passwd *nwrap_files_getpwuid(uid_t uid) return NULL; } -static int nwrap_files_getpwuid_r(uid_t uid, struct passwd *pwdst, +static int nwrap_files_getpwuid_r(struct nwrap_backend *b, + uid_t uid, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { struct passwd *pw; - pw = nwrap_files_getpwuid(uid); + pw = nwrap_files_getpwuid(b, uid); if (!pw) { if (errno == 0) { return ENOENT; @@ -945,12 +1012,12 @@ static int nwrap_files_getpwuid_r(uid_t uid, struct passwd *pwdst, } /* user enum functions */ -static void nwrap_files_setpwent(void) +static void nwrap_files_setpwent(struct nwrap_backend *b) { nwrap_pw_global.idx = 0; } -static struct passwd *nwrap_files_getpwent(void) +static struct passwd *nwrap_files_getpwent(struct nwrap_backend *b) { struct passwd *pw; @@ -971,12 +1038,13 @@ static struct passwd *nwrap_files_getpwent(void) return pw; } -static int nwrap_files_getpwent_r(struct passwd *pwdst, char *buf, +static int nwrap_files_getpwent_r(struct nwrap_backend *b, + struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { struct passwd *pw; - pw = nwrap_files_getpwent(); + pw = nwrap_files_getpwent(b); if (!pw) { if (errno == 0) { return ENOENT; @@ -987,20 +1055,22 @@ static int nwrap_files_getpwent_r(struct passwd *pwdst, char *buf, return nwrap_pw_copy_r(pw, pwdst, buf, buflen, pwdstp); } -static void nwrap_files_endpwent(void) +static void nwrap_files_endpwent(struct nwrap_backend *b) { nwrap_pw_global.idx = 0; } /* misc functions */ -static int nwrap_files_initgroups(const char *user, gid_t group) +static int nwrap_files_initgroups(struct nwrap_backend *b, + const char *user, gid_t group) { /* TODO: maybe we should also fake this... */ return EPERM; } /* group functions */ -static struct group *nwrap_files_getgrnam(const char *name) +static struct group *nwrap_files_getgrnam(struct nwrap_backend *b, + const char *name) { int i; @@ -1023,12 +1093,13 @@ static struct group *nwrap_files_getgrnam(const char *name) return NULL; } -static int nwrap_files_getgrnam_r(const char *name, struct group *grdst, +static int nwrap_files_getgrnam_r(struct nwrap_backend *b, + const char *name, struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { struct group *gr; - gr = nwrap_files_getgrnam(name); + gr = nwrap_files_getgrnam(b, name); if (!gr) { if (errno == 0) { return ENOENT; @@ -1039,7 +1110,8 @@ static int nwrap_files_getgrnam_r(const char *name, struct group *grdst, return nwrap_gr_copy_r(gr, grdst, buf, buflen, grdstp); } -static struct group *nwrap_files_getgrgid(gid_t gid) +static struct group *nwrap_files_getgrgid(struct nwrap_backend *b, + gid_t gid) { int i; @@ -1062,12 +1134,13 @@ static struct group *nwrap_files_getgrgid(gid_t gid) return NULL; } -static int nwrap_files_getgrgid_r(gid_t gid, struct group *grdst, +static int nwrap_files_getgrgid_r(struct nwrap_backend *b, + gid_t gid, struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { struct group *gr; - gr = nwrap_files_getgrgid(gid); + gr = nwrap_files_getgrgid(b, gid); if (!gr) { if (errno == 0) { return ENOENT; @@ -1079,12 +1152,12 @@ static int nwrap_files_getgrgid_r(gid_t gid, struct group *grdst, } /* group enum functions */ -static void nwrap_files_setgrent(void) +static void nwrap_files_setgrent(struct nwrap_backend *b) { nwrap_gr_global.idx = 0; } -static struct group *nwrap_files_getgrent(void) +static struct group *nwrap_files_getgrent(struct nwrap_backend *b) { struct group *gr; @@ -1105,12 +1178,13 @@ static struct group *nwrap_files_getgrent(void) return gr; } -static int nwrap_files_getgrent_r(struct group *grdst, char *buf, +static int nwrap_files_getgrent_r(struct nwrap_backend *b, + struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { struct group *gr; - gr = nwrap_files_getgrent(); + gr = nwrap_files_getgrent(b); if (!gr) { if (errno == 0) { return ENOENT; @@ -1121,7 +1195,7 @@ static int nwrap_files_getgrent_r(struct group *grdst, char *buf, return nwrap_gr_copy_r(gr, grdst, buf, buflen, grdstp); } -static void nwrap_files_endgrent(void) +static void nwrap_files_endgrent(struct nwrap_backend *b) { nwrap_gr_global.idx = 0; } @@ -1132,64 +1206,126 @@ static void nwrap_files_endgrent(void) _PUBLIC_ struct passwd *nwrap_getpwnam(const char *name) { + int i; + struct passwd *pwd; + if (!nwrap_enabled()) { return real_getpwnam(name); } - return nwrap_main_global->ops->nw_getpwnam(name); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + pwd = b->ops->nw_getpwnam(b, name); + if (pwd) { + return pwd; + } + } + + return NULL; } _PUBLIC_ int nwrap_getpwnam_r(const char *name, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { + int i,ret; + if (!nwrap_enabled()) { return real_getpwnam_r(name, pwdst, buf, buflen, pwdstp); } - return nwrap_main_global->ops->nw_getpwnam_r(name, pwdst, buf, buflen, pwdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getpwnam_r(b, name, pwdst, buf, buflen, pwdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ struct passwd *nwrap_getpwuid(uid_t uid) { + int i; + struct passwd *pwd; + if (!nwrap_enabled()) { return real_getpwuid(uid); } - return nwrap_main_global->ops->nw_getpwuid(uid); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + pwd = b->ops->nw_getpwuid(b, uid); + if (pwd) { + return pwd; + } + } + + return NULL; } _PUBLIC_ int nwrap_getpwuid_r(uid_t uid, struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { + int i,ret; + if (!nwrap_enabled()) { return real_getpwuid_r(uid, pwdst, buf, buflen, pwdstp); } - return nwrap_main_global->ops->nw_getpwuid_r(uid, pwdst, buf, buflen, pwdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getpwuid_r(b, uid, pwdst, buf, buflen, pwdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ void nwrap_setpwent(void) { + int i; + if (!nwrap_enabled()) { real_setpwent(); return; } - nwrap_main_global->ops->nw_setpwent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + b->ops->nw_setpwent(b); + } } _PUBLIC_ struct passwd *nwrap_getpwent(void) { + int i; + struct passwd *pwd; + if (!nwrap_enabled()) { return real_getpwent(); } - return nwrap_main_global->ops->nw_getpwent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + pwd = b->ops->nw_getpwent(b); + if (pwd) { + return pwd; + } + } + + return NULL; } _PUBLIC_ int nwrap_getpwent_r(struct passwd *pwdst, char *buf, size_t buflen, struct passwd **pwdstp) { + int i,ret; + if (!nwrap_enabled()) { #ifdef SOLARIS_GETPWENT_R struct passwd *pw; @@ -1209,88 +1345,172 @@ _PUBLIC_ int nwrap_getpwent_r(struct passwd *pwdst, char *buf, #endif } - return nwrap_main_global->ops->nw_getpwent_r(pwdst, buf, buflen, pwdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getpwent_r(b, pwdst, buf, buflen, pwdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ void nwrap_endpwent(void) { + int i; + if (!nwrap_enabled()) { real_endpwent(); return; } - nwrap_main_global->ops->nw_endpwent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + b->ops->nw_endpwent(b); + } } _PUBLIC_ int nwrap_initgroups(const char *user, gid_t group) { + int i; + if (!nwrap_enabled()) { return real_initgroups(user, group); } - return nwrap_main_global->ops->nw_initgroups(user, group); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + return b->ops->nw_initgroups(b, user, group); + } + + errno = ENOENT; + return -1; } _PUBLIC_ struct group *nwrap_getgrnam(const char *name) { + int i; + struct group *grp; + if (!nwrap_enabled()) { return real_getgrnam(name); } - return nwrap_main_global->ops->nw_getgrnam(name); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + grp = b->ops->nw_getgrnam(b, name); + if (grp) { + return grp; + } + } + + return NULL; } _PUBLIC_ int nwrap_getgrnam_r(const char *name, struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { + int i,ret; + if (!nwrap_enabled()) { return real_getgrnam_r(name, grdst, buf, buflen, grdstp); } - return nwrap_main_global->ops->nw_getgrnam_r(name, grdst, buf, buflen, grdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getgrnam_r(b, name, grdst, buf, buflen, grdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ struct group *nwrap_getgrgid(gid_t gid) { + int i; + struct group *grp; + if (!nwrap_enabled()) { return real_getgrgid(gid); } - return nwrap_main_global->ops->nw_getgrgid(gid); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + grp = b->ops->nw_getgrgid(b, gid); + if (grp) { + return grp; + } + } + + return NULL; } _PUBLIC_ int nwrap_getgrgid_r(gid_t gid, struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { + int i,ret; + if (!nwrap_enabled()) { return real_getgrgid_r(gid, grdst, buf, buflen, grdstp); } - return nwrap_main_global->ops->nw_getgrgid_r(gid, grdst, buf, buflen, grdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getgrgid_r(b, gid, grdst, buf, buflen, grdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ void nwrap_setgrent(void) { + int i; + if (!nwrap_enabled()) { real_setgrent(); return; } - nwrap_main_global->ops->nw_setgrent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + b->ops->nw_setgrent(b); + } } _PUBLIC_ struct group *nwrap_getgrent(void) { + int i; + struct group *grp; + if (!nwrap_enabled()) { return real_getgrent(); } - return nwrap_main_global->ops->nw_getgrent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + grp = b->ops->nw_getgrent(b); + if (grp) { + return grp; + } + } + + return NULL; } _PUBLIC_ int nwrap_getgrent_r(struct group *grdst, char *buf, size_t buflen, struct group **grdstp) { + int i,ret; + if (!nwrap_enabled()) { #ifdef SOLARIS_GETGRENT_R struct group *gr; @@ -1310,17 +1530,31 @@ _PUBLIC_ int nwrap_getgrent_r(struct group *grdst, char *buf, #endif } - return nwrap_main_global->ops->nw_getgrent_r(grdst, buf, buflen, grdstp); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + ret = b->ops->nw_getgrent_r(b, grdst, buf, buflen, grdstp); + if (ret == ENOENT) { + continue; + } + return ret; + } + + return ENOENT; } _PUBLIC_ void nwrap_endgrent(void) { + int i; + if (!nwrap_enabled()) { real_endgrent(); return; } - nwrap_main_global->ops->nw_endgrent(); + for (i=0; i < nwrap_main_global->num_backends; i++) { + struct nwrap_backend *b = &nwrap_main_global->backends[i]; + b->ops->nw_endgrent(b); + } } _PUBLIC_ int nwrap_getgrouplist(const char *user, gid_t group, gid_t *groups, int *ngroups) @@ -1377,6 +1611,7 @@ _PUBLIC_ int nwrap_getgrouplist(const char *user, gid_t group, gid_t *groups, in } } } + nwrap_endgrent(); NWRAP_VERBOSE(("%s: %s is member of %d groups: %d\n", -- cgit