ref: 556618eb07d1ac6e2c629a60acd53c45d53261be
dir: /sys/src/cmd/ip/cifsd/idmap.c/
#include <u.h> #include <libc.h> #include "dat.h" #include "fns.h" #include <bio.h> enum { NHASH = 251, }; typedef struct Ident Ident; struct Ident { Ident *nextid; Ident *nextname; int id; char name[]; }; struct Idmap { Ident *tab[NHASH]; }; static Ident** nametab(Idmap *map, char *name) { return &map->tab[(uint)namehash(name) % NHASH]; } static Ident** idtab(Idmap *map, int id) { return &map->tab[(uint)id % NHASH]; } static int name2id(Idmap *map, char *name) { Ident *e; for(e = *nametab(map, name); e != nil; e = e->nextid){ if(strcmp(e->name, name) == 0) return e->id; } return -1; } static char* id2name(Idmap *map, int id) { Ident *e; for(e = *idtab(map, id); e != nil; e = e->nextname){ if(e->id == id) return e->name; } return nil; } static void idmap(Idmap *map, char *name, int id) { Ident *e, **h; int n; n = strlen(name)+1; e = malloc(sizeof(Ident)+n); if(e == nil) return; e->id = id; h = idtab(map, e->id); e->nextid = *h; *h = e; memmove(e->name, name, n); h = nametab(map, e->name); e->nextname = *h; *h = e; } static Idmap* readidmap(char *file, int style) { Biobuf *b; Idmap *m; char *l, *name; int id; if((b = Bopen(file, OREAD)) == nil) return nil; if((m = mallocz(sizeof(*m), 1)) == nil) goto Out; while((l = Brdline(b, '\n')) != nil){ l[Blinelen(b)-1] = 0; switch(style){ case '9': id = 9000000 + strtol(l, &l, 10); if(*l != ':') continue; name = ++l; l = strchr(l, ':'); if(l == 0) continue; *l = 0; break; default: name = l; l = strchr(l, ':'); if(l == 0) continue; *l++ = 0; /* skip password */ l = strchr(l, ':'); if(l == 0) continue; id = strtol(l+1, 0, 10); break; } idmap(m, name, id); } Out: Bterm(b); return m; } void unixidmap(Share *share) { static Idmap emptymap; char *file; if(share->stype != STYPE_DISKTREE) goto Out; file = smprint("%s/etc/passwd", share->root); share->users = readidmap(file, 'u'); free(file); file = smprint("%s/etc/group", share->root); share->groups = readidmap(file, 'u'); free(file); if(share->users != nil && share->groups != nil) return; file = smprint("%s/adm/users", share->root); share->users = share->groups = readidmap(file, '9'); free(file); if(share->users != nil && share->groups != nil) return; Out: share->users = share->groups = &emptymap; } char* unixname(Share *share, int id, int group) { return id2name(group? share->groups: share->users, id); } int unixuid(Share *share, char *name) { return name2id(share->users, name); } int unixgid(Share *share, char *name) { return name2id(share->groups, name); }