X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/checkpath/blobdiff_plain/f797fd4aa7bdf4c344dd846eb63e1f2cf3a53fe0..972ca7cda65ce3fc9f150c20a56ad4836f3a7414:/checkpath.c diff --git a/checkpath.c b/checkpath.c index e4d83e1..2cb73cd 100644 --- a/checkpath.c +++ b/checkpath.c @@ -44,6 +44,7 @@ #include #include #include +#include #include "checkpath.h" @@ -64,8 +65,11 @@ struct elt { }; struct state { + pool *p; /* Allocation pool */ struct elt *sp; /* Stack pointer for list */ dstr path; /* Current path string */ + dstr link; /* Symbolic link target string */ + dstr msg; /* Message string */ }; /*----- Static variables --------------------------------------------------*/ @@ -76,7 +80,8 @@ static const struct elt rootnode = { 0, 0, 0 }; /* Root of the list */ /* --- @splitpath@ --- * * - * Arguments: @const char *path@ = path string to break apart + * Arguments: @struct state *state@ = pointer to state + * @const char *path@ = path string to break apart * @struct elt *tail@ = tail block to attach to end of list * * Returns: Pointer to the new list head. @@ -86,7 +91,8 @@ static const struct elt rootnode = { 0, 0, 0 }; /* Root of the list */ * be pushed onto the directory stack as required. */ -static struct elt *splitpath(const char *path, struct elt *tail) +static struct elt *splitpath(struct state *state, + const char *path, struct elt *tail) { struct elt *head, **ee = &head, *e; size_t n; @@ -109,7 +115,7 @@ static struct elt *splitpath(const char *path, struct elt *tail) */ n = strcspn(path, "/"); - e = xmalloc(sizeof(struct elt) + n + 1); + e = pool_alloc(state->p, offsetof(struct elt, e_name) + n + 1); memcpy(e->e_name, path, n); e->e_name[n] = 0; e->e_flags = 0; @@ -141,7 +147,7 @@ static void pop(struct state *state) e = sp->e_link; state->path.len = sp->e_offset; DPUTZ(&state->path); - xfree(state->sp); state->sp = e; + state->sp = e; } } @@ -155,7 +161,7 @@ static void pop(struct state *state) */ static void popall(struct state *state) - { while (state->sp->e_link) pop(state); } + { state->sp = (/*unconst*/ struct elt *)&rootnode; state->path.len = 0; } /* --- @push@ --- * * @@ -178,7 +184,8 @@ static void push(struct state *state, struct elt *e) /* --- @report@ --- * * - * Arguments: @const struct checkpath *cp@ = pointer to query + * Arguments: @struct state *state@ = pointer to state + * @const struct checkpath *cp@ = pointer to query * @unsigned what@ = what sort of report is this? * @int verbose@ = how verbose is this? * @const char *p@ = what path does it refer to? @@ -189,10 +196,10 @@ static void push(struct state *state, struct elt *e) * Use: Formats and presents messages to the client. */ -static void report(const struct checkpath *cp, unsigned what, int verbose, +static void report(struct state *state, const struct checkpath *cp, + unsigned what, int verbose, const char *p, const char *msg, ...) { - dstr d = DSTR_INIT; va_list ap; const char *q = msg; const char *s; @@ -217,56 +224,56 @@ static void report(const struct checkpath *cp, unsigned what, int verbose, /* --- Format the message nicely --- */ + dstr_reset(&state->msg); va_start(ap, msg); if (verbose > 1) - dstr_puts(&d, "[ "); + dstr_puts(&state->msg, "[ "); if (p) - dstr_putf(&d, "Path: %s: ", p); + dstr_putf(&state->msg, "Path: %s: ", p); while (*q) { if (*q == '%') { q++; switch (*q) { case 'e': - dstr_puts(&d, strerror(e)); + dstr_puts(&state->msg, strerror(e)); break; case 'u': - u = (uid_t)va_arg(ap, int); + u = (uid_t)va_arg(ap, long); if ((pw = getpwuid(u)) != 0) - dstr_putf(&d, "`%s'", pw->pw_name); + dstr_putf(&state->msg, "`%s'", pw->pw_name); else - dstr_putf(&d, "%i", (int)u); + dstr_putf(&state->msg, "#%ld", (long)u); break; case 'g': - g = (gid_t)va_arg(ap, int); + g = (gid_t)va_arg(ap, long); if ((gr = getgrgid(g)) != 0) - dstr_putf(&d, "`%s'", gr->gr_name); + dstr_putf(&state->msg, "`%s'", gr->gr_name); else - dstr_putf(&d, "%i", (int)g); + dstr_putf(&state->msg, "#%ld", (long)g); break; case 's': s = va_arg(ap, const char *); - dstr_puts(&d, s); + dstr_puts(&state->msg, s); break; case '%': - dstr_putc(&d, '%'); + dstr_putc(&state->msg, '%'); break; default: - dstr_putc(&d, '%'); - dstr_putc(&d, *q); + dstr_putc(&state->msg, '%'); + dstr_putc(&state->msg, *q); break; } q++; } else { n = strcspn(q, "%"); - DPUTM(&d, q, n); + DPUTM(&state->msg, q, n); q += n; } } if (verbose > 1) - dstr_puts(&d, " ]"); - DPUTZ(&d); - cp->cp_report(what, verbose, p, d.buf, cp->cp_arg); - dstr_destroy(&d); + dstr_puts(&state->msg, " ]"); + DPUTZ(&state->msg); + cp->cp_report(what, verbose, p, state->msg.buf, cp->cp_arg); va_end(ap); } @@ -274,6 +281,7 @@ static void report(const struct checkpath *cp, unsigned what, int verbose, * * Arguments: @const char *p@ = name of directory to check * @struct stat *st@ = pointer to @stat@(2) block for it + * @struct state *state@ = pointer to state * @const struct checkpath *cp@ = pointer to query * @unsigned f@ = various flags (@SF_...@) * @@ -287,7 +295,8 @@ static void report(const struct checkpath *cp, unsigned what, int verbose, #define SF_LAST 1u /* This is the final item to check */ static unsigned sanity(const char *p, struct stat *st, - const struct checkpath *cp, unsigned f) + struct state *state, const struct checkpath *cp, + unsigned f) { unsigned bad = 0; int stickyok = 0; @@ -303,7 +312,7 @@ static unsigned sanity(const char *p, struct stat *st, if ((cp->cp_what & CP_WRWORLD) && (st->st_mode & (S_IWOTH | stickyok)) == S_IWOTH) { bad |= CP_WRWORLD; - report(cp, CP_WRWORLD, 1, p, "** world writable **"); + report(state, cp, CP_WRWORLD, 1, p, "** world writable **"); } /* --- Check for group-writability --- */ @@ -321,8 +330,8 @@ static unsigned sanity(const char *p, struct stat *st, } if (b) { bad |= b; - report(cp, b, 1, p, "writable by %sgroup %g", - (b == CP_WROTHGRP) ? "other " : "", st->st_gid); + report(state, cp, b, 1, p, "writable by %sgroup %g", + (b == CP_WROTHGRP) ? "other " : "", (long)st->st_gid); } } @@ -332,7 +341,8 @@ static unsigned sanity(const char *p, struct stat *st, st->st_uid != cp->cp_uid && st->st_uid != 0) { bad |= CP_WROTHUSR; - report(cp, CP_WROTHUSR, 1, p, "owner is user %u", st->st_uid); + report(state, cp, CP_WROTHUSR, 1, p, + "owner is user %u", (long)st->st_uid); } /* --- Done sanity check --- */ @@ -355,39 +365,44 @@ unsigned checkpath(const char *p, const struct checkpath *cp) { char cwd[PATH_MAX]; struct elt *e, *ee; - struct state state; + struct state *state; + pool *pp; struct stat st; unsigned bad = 0; - dstr buf = DSTR_INIT; int i; /* --- Initialize the state --- */ - state.sp = (/*unconst*/ struct elt *)&rootnode; - dstr_create(&state.path); + pp = pool_create(arena_global); + state = pool_alloc(pp, sizeof(*state)); + state->p = pp; + state->sp = (/*unconst*/ struct elt *)&rootnode; + dstr_create(&state->path); + dstr_create(&state->link); + dstr_create(&state->msg); /* --- Try to find the current directory --- */ if (!getcwd(cwd, sizeof(cwd))) { - report(cp, CP_ERROR, 0, 0, "can't find current directory: %e"); + report(state, cp, CP_ERROR, 0, 0, "can't find current directory: %e"); return (CP_ERROR); } /* --- Check that the root directory is OK --- */ if (stat("/", &st)) { - report(cp, CP_ERROR, 0, 0, "can't stat root directory: %e"); + report(state, cp, CP_ERROR, 0, 0, "can't stat root directory: %e"); return (CP_ERROR); } - report(cp, CP_REPORT, 3, p, "begin scan"); - bad |= sanity("/", &st, cp, 0); + report(state, cp, CP_REPORT, 3, p, "begin scan"); + bad |= sanity("/", &st, state, cp, 0); /* --- Get the initial list of things to process --- */ - ee = splitpath(p, 0); + ee = splitpath(state, p, 0); if (*p != '/') - ee = splitpath(cwd, ee); + ee = splitpath(state, cwd, ee); /* --- While there are list items which still need doing --- */ @@ -397,7 +412,6 @@ unsigned checkpath(const char *p, const struct checkpath *cp) /* --- Strip off simple `.' elements --- */ if (strcmp(ee->e_name, ".") == 0) { - xfree(ee); ee = e; continue; } @@ -405,21 +419,20 @@ unsigned checkpath(const char *p, const struct checkpath *cp) /* --- Backtrack on `..' elements --- */ else if (strcmp(ee->e_name, "..") == 0) { - pop(&state); - xfree(ee); + pop(state); ee = e; continue; } /* --- Everything else gets pushed on the end --- */ - push(&state, ee); + push(state, ee); ee = e; /* --- Find out what sort of a thing this is --- */ - if (lstat(state.path.buf, &st)) { - report(cp, CP_ERROR, 0, state.path.buf, "can't stat: %e"); + if (lstat(state->path.buf, &st)) { + report(state, cp, CP_ERROR, 0, state->path.buf, "can't stat: %e"); bad |= CP_ERROR; break; } @@ -430,15 +443,18 @@ unsigned checkpath(const char *p, const struct checkpath *cp) /* --- Resolve the link --- */ - dstr_reset(&buf); - dstr_ensure(&buf, st.st_size + 1); - if ((i = readlink(state.path.buf, buf.buf, buf.sz)) < 0) { - report(cp, CP_ERROR, 0, state.path.buf, "can't readlink: %e"); + dstr_reset(&state->link); + dstr_ensure(&state->link, st.st_size + 1); + if ((i = readlink(state->path.buf, + state->link.buf, state->link.sz)) < 0) { + report(state, cp, CP_ERROR, 0, state->path.buf, + "can't readlink: %e"); bad |= CP_ERROR; break; } - buf.buf[i] = 0; - report(cp, CP_SYMLINK, 2, state.path.buf, "symlink -> `%s'", buf.buf); + state->link.buf[i] = 0; + report(state, cp, CP_SYMLINK, 2, state->path.buf, + "symlink -> `%s'", state->link.buf); /* --- Handle sticky parents --- * * @@ -448,31 +464,31 @@ unsigned checkpath(const char *p, const struct checkpath *cp) */ if ((cp->cp_what & CP_WROTHUSR) && - (state.sp->e_link->e_flags & EF_STICKY) && + (state->sp->e_link->e_flags & EF_STICKY) && st.st_uid != cp->cp_uid && st.st_uid != 0) { bad |= CP_WROTHUSR; - report(cp, CP_WROTHUSR, 1, state.path.buf, - "symlink modifiable by user %u", st.st_uid); + report(state, cp, CP_WROTHUSR, 1, state->path.buf, + "symlink modifiable by user %u", (long)st.st_uid); } /* --- Sort out what to do from here --- */ - if (buf.buf[0] == '/') - popall(&state); + if (state->link.buf[0] == '/') + popall(state); else - pop(&state); - ee = splitpath(buf.buf, ee); + pop(state); + ee = splitpath(state, state->link.buf, ee); continue; } /* --- Run the sanity check on this path element --- */ - bad |= sanity(state.path.buf, &st, cp, ee ? 0 : SF_LAST); + bad |= sanity(state->path.buf, &st, state, cp, ee ? 0 : SF_LAST); if (S_ISDIR(st.st_mode)) { if (st.st_mode & S_ISVTX) - state.sp->e_flags |= EF_STICKY; - report(cp, CP_REPORT, 4, state.path.buf, "directory"); + state->sp->e_flags |= EF_STICKY; + report(state, cp, CP_REPORT, 4, state->path.buf, "directory"); continue; } @@ -485,17 +501,17 @@ unsigned checkpath(const char *p, const struct checkpath *cp) if (ee) { if (!(bad & CP_ERROR)) - report(cp, CP_ERROR, 0, 0, "junk left over after reaching leaf"); + report(state, cp, CP_ERROR, 0, 0, "junk left over after reaching leaf"); while (ee) { e = ee->e_link; - xfree(ee); ee = e; } } - popall(&state); - dstr_destroy(&state.path); - dstr_destroy(&buf); + dstr_destroy(&state->path); + dstr_destroy(&state->link); + dstr_destroy(&state->msg); + pool_destroy(state->p); return (bad); }