mirror of
git://git.gnu.org.ua/pam-modules.git
synced 2025-04-26 00:19:52 +03:00
696 lines
15 KiB
C
696 lines
15 KiB
C
/* This file is part of pam_modules.
|
||
Copyright (C) 2006-2022 Sergey Poznyakoff.
|
||
(using my implementation for the GNU tar).
|
||
|
||
This program is free software; you can redistribute it and/or modify it
|
||
under the terms of the GNU General Public License as published by the
|
||
Free Software Foundation; either version 3, or (at your option) any later
|
||
version.
|
||
|
||
This program is distributed in the hope that it will be useful, but
|
||
WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
|
||
Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License along
|
||
with this program; if not, write to the Free Software Foundation, Inc.,
|
||
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
|
||
|
||
#include <graypam.h>
|
||
|
||
enum transform_type
|
||
{
|
||
transform_first,
|
||
transform_global
|
||
};
|
||
|
||
enum replace_segm_type
|
||
{
|
||
segm_literal, /* Literal segment */
|
||
segm_backref, /* Back-reference segment */
|
||
segm_case_ctl /* Case control segment (GNU extension) */
|
||
};
|
||
|
||
enum case_ctl_type
|
||
{
|
||
ctl_stop, /* Stop case conversion */
|
||
ctl_upcase_next,/* Turn the next character to uppercase */
|
||
ctl_locase_next,/* Turn the next character to lowercase */
|
||
ctl_upcase, /* Turn the replacement to uppercase until ctl_stop */
|
||
ctl_locase /* Turn the replacement to lowercase until ctl_stop */
|
||
};
|
||
|
||
struct replace_segm
|
||
{
|
||
struct replace_segm *next;
|
||
enum replace_segm_type type;
|
||
union
|
||
{
|
||
struct
|
||
{
|
||
char *ptr;
|
||
size_t size;
|
||
} literal; /* type == segm_literal */
|
||
size_t ref; /* type == segm_backref */
|
||
enum case_ctl_type ctl; /* type == segm_case_ctl */
|
||
} v;
|
||
};
|
||
|
||
struct transform
|
||
{
|
||
struct transform *next;
|
||
enum transform_type transform_type;
|
||
unsigned match_number;
|
||
regex_t regex;
|
||
int has_regex;
|
||
int error;
|
||
/* Compiled replacement expression */
|
||
struct replace_segm *repl_head, *repl_tail;
|
||
size_t segm_count; /* Number of elements in the above list */
|
||
};
|
||
|
||
static inline int
|
||
transform_err(struct transform *tf)
|
||
{
|
||
return tf->error;
|
||
}
|
||
|
||
static void
|
||
transform_seterr (struct transform *tf, int ec)
|
||
{
|
||
errno_to_pam (errno);
|
||
tf->error = ec;
|
||
}
|
||
|
||
|
||
static struct transform *transform_head, *transform_tail;
|
||
static char *case_ctl_buffer;
|
||
static size_t case_ctl_bufsize;
|
||
|
||
static struct transform *
|
||
new_transform (void)
|
||
{
|
||
struct transform *p = calloc (1, sizeof *p);
|
||
if (p)
|
||
{
|
||
if (transform_tail)
|
||
transform_tail->next = p;
|
||
else
|
||
transform_head = p;
|
||
transform_tail = p;
|
||
}
|
||
return p;
|
||
}
|
||
|
||
static void free_segment (struct replace_segm *segm);
|
||
|
||
static void
|
||
free_transform (struct transform *tr)
|
||
{
|
||
struct replace_segm *segm;
|
||
if (tr->has_regex)
|
||
regfree (&tr->regex);
|
||
for (segm = tr->repl_head; segm; )
|
||
{
|
||
struct replace_segm *next = segm->next;
|
||
free_segment (segm);
|
||
segm = next;
|
||
}
|
||
}
|
||
|
||
static struct replace_segm *
|
||
add_segment (struct transform *tf)
|
||
{
|
||
struct replace_segm *segm = malloc (sizeof *segm);
|
||
if (segm)
|
||
{
|
||
segm->next = NULL;
|
||
if (tf->repl_tail)
|
||
tf->repl_tail->next = segm;
|
||
else
|
||
tf->repl_head = segm;
|
||
tf->repl_tail = segm;
|
||
tf->segm_count++;
|
||
}
|
||
else
|
||
transform_seterr (tf, errno_to_pam (errno));
|
||
return segm;
|
||
}
|
||
|
||
static void
|
||
free_segment (struct replace_segm *segm)
|
||
{
|
||
if (segm->type == segm_literal)
|
||
free (segm->v.literal.ptr);
|
||
free (segm);
|
||
}
|
||
|
||
static void
|
||
add_literal_segment (struct transform *tf, char const *str, char const *end)
|
||
{
|
||
size_t len = end - str;
|
||
if (len)
|
||
{
|
||
struct replace_segm *segm = add_segment (tf);
|
||
if (segm)
|
||
{
|
||
segm->type = segm_literal;
|
||
segm->v.literal.ptr = malloc (len + 1);
|
||
if (segm->v.literal.ptr)
|
||
{
|
||
memcpy (segm->v.literal.ptr, str, len);
|
||
segm->v.literal.ptr[len] = 0;
|
||
segm->v.literal.size = len;
|
||
}
|
||
else
|
||
transform_seterr (tf, errno_to_pam (errno));
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
add_char_segment (struct transform *tf, int chr)
|
||
{
|
||
struct replace_segm *segm = add_segment (tf);
|
||
if (segm)
|
||
{
|
||
segm->type = segm_literal;
|
||
segm->v.literal.ptr = malloc (2);
|
||
if (segm->v.literal.ptr)
|
||
{
|
||
segm->v.literal.ptr[0] = chr;
|
||
segm->v.literal.ptr[1] = 0;
|
||
segm->v.literal.size = 1;
|
||
}
|
||
else
|
||
transform_seterr (tf, errno_to_pam (errno));
|
||
}
|
||
}
|
||
|
||
static void
|
||
add_backref_segment (struct transform *tf, size_t ref)
|
||
{
|
||
struct replace_segm *segm = add_segment (tf);
|
||
if (segm)
|
||
{
|
||
segm->type = segm_backref;
|
||
segm->v.ref = ref;
|
||
}
|
||
}
|
||
|
||
static void
|
||
add_case_ctl_segment (struct transform *tf, enum case_ctl_type ctl)
|
||
{
|
||
struct replace_segm *segm = add_segment (tf);
|
||
if (segm)
|
||
{
|
||
segm->type = segm_case_ctl;
|
||
segm->v.ctl = ctl;
|
||
}
|
||
}
|
||
|
||
static int
|
||
parse_transform_expr (const char *expr, const char **endp)
|
||
{
|
||
int delim;
|
||
int i, j, rc;
|
||
char *str;
|
||
const char *beg;
|
||
const char *cur;
|
||
const char *p;
|
||
int cflags = 0;
|
||
struct transform *tf = new_transform ();
|
||
|
||
if (expr[0] != 's')
|
||
{
|
||
_pam_log(LOG_ERR, "invalid transform expression");
|
||
*endp = expr;
|
||
return PAM_SERVICE_ERR;
|
||
}
|
||
|
||
delim = expr[1];
|
||
|
||
/* Scan regular expression */
|
||
for (i = 2; expr[i] && expr[i] != delim; i++)
|
||
if (expr[i] == '\\' && expr[i+1])
|
||
i++;
|
||
|
||
if (expr[i] != delim)
|
||
{
|
||
_pam_log(LOG_ERR, "invalid transform expression");
|
||
*endp = expr + i;
|
||
return PAM_SERVICE_ERR;
|
||
}
|
||
|
||
/* Scan replacement expression */
|
||
for (j = i + 1; expr[j] && expr[j] != delim; j++)
|
||
if (expr[j] == '\\' && expr[j+1])
|
||
j++;
|
||
|
||
if (expr[j] != delim)
|
||
{
|
||
_pam_log(LOG_ERR, "invalid transform expression");
|
||
*endp = expr + j;
|
||
return PAM_SERVICE_ERR;
|
||
}
|
||
|
||
/* Check flags */
|
||
tf->transform_type = transform_first;
|
||
for (p = expr + j + 1; *p && *p != ';'; p++)
|
||
switch (*p)
|
||
{
|
||
case 'g':
|
||
tf->transform_type = transform_global;
|
||
break;
|
||
|
||
case 'i':
|
||
cflags |= REG_ICASE;
|
||
break;
|
||
|
||
case 'x':
|
||
cflags |= REG_EXTENDED;
|
||
break;
|
||
|
||
case '0': case '1': case '2': case '3': case '4':
|
||
case '5': case '6': case '7': case '8': case '9':
|
||
tf->match_number = strtoul (p, (char**) &p, 0);
|
||
p--;
|
||
break;
|
||
|
||
default:
|
||
_pam_log(LOG_ERR, "unknown flag in transform expression: %c", *p);
|
||
*endp = p;
|
||
return PAM_SERVICE_ERR;
|
||
}
|
||
|
||
if (*p == ';')
|
||
p++;
|
||
|
||
/* Extract and compile regex */
|
||
str = malloc (i - 1);
|
||
if (!str)
|
||
{
|
||
*endp = p;
|
||
return errno_to_pam (errno);
|
||
}
|
||
memcpy (str, expr + 2, i - 2);
|
||
str[i - 2] = 0;
|
||
|
||
rc = regcomp (&tf->regex, str, cflags);
|
||
|
||
if (rc)
|
||
{
|
||
char errbuf[512];
|
||
regerror (rc, &tf->regex, errbuf, sizeof (errbuf));
|
||
_pam_log(LOG_ERR, "invalid transform expression: %s", errbuf);
|
||
free (str);
|
||
*endp = p;
|
||
return PAM_SERVICE_ERR;
|
||
}
|
||
tf->has_regex = 1;
|
||
if (str[0] == '^' || str[strlen (str) - 1] == '$')
|
||
tf->transform_type = transform_first;
|
||
|
||
free (str);
|
||
|
||
/* Extract and compile replacement expr */
|
||
i++;
|
||
str = malloc (j - i + 1);
|
||
if (!str)
|
||
{
|
||
*endp = p;
|
||
return errno_to_pam (errno);
|
||
}
|
||
|
||
memcpy (str, expr + i, j - i);
|
||
str[j - i] = 0;
|
||
|
||
for (cur = beg = str; *cur;)
|
||
{
|
||
if (transform_err (tf))
|
||
{
|
||
*endp = expr + i + (beg - str);
|
||
free (str);
|
||
return transform_err (tf);
|
||
}
|
||
|
||
if (*cur == '\\')
|
||
{
|
||
size_t n;
|
||
|
||
add_literal_segment (tf, beg, cur);
|
||
switch (*++cur)
|
||
{
|
||
case '0': case '1': case '2': case '3': case '4':
|
||
case '5': case '6': case '7': case '8': case '9':
|
||
n = strtoul (cur, (char**)&cur, 10);
|
||
if (n > tf->regex.re_nsub)
|
||
{
|
||
_pam_log(LOG_ERR,
|
||
"invalid transform replacement: "
|
||
"back reference out of range");
|
||
transform_seterr (tf, PAM_SERVICE_ERR);
|
||
}
|
||
else
|
||
add_backref_segment (tf, n);
|
||
break;
|
||
|
||
case '\\':
|
||
add_char_segment (tf, '\\');
|
||
cur++;
|
||
break;
|
||
|
||
case 'a':
|
||
add_char_segment (tf, '\a');
|
||
cur++;
|
||
break;
|
||
|
||
case 'b':
|
||
add_char_segment (tf, '\b');
|
||
cur++;
|
||
break;
|
||
|
||
case 'f':
|
||
add_char_segment (tf, '\f');
|
||
cur++;
|
||
break;
|
||
|
||
case 'n':
|
||
add_char_segment (tf, '\n');
|
||
cur++;
|
||
break;
|
||
|
||
case 'r':
|
||
add_char_segment (tf, '\r');
|
||
cur++;
|
||
break;
|
||
|
||
case 't':
|
||
add_char_segment (tf, '\t');
|
||
cur++;
|
||
break;
|
||
|
||
case 'v':
|
||
add_char_segment (tf, '\v');
|
||
cur++;
|
||
break;
|
||
|
||
case '&':
|
||
add_char_segment (tf, '&');
|
||
cur++;
|
||
break;
|
||
|
||
case 'L':
|
||
/* Turn the replacement to lowercase until a `\U' or `\E'
|
||
is found, */
|
||
add_case_ctl_segment (tf, ctl_locase);
|
||
cur++;
|
||
break;
|
||
|
||
case 'l':
|
||
/* Turn the next character to lowercase, */
|
||
add_case_ctl_segment (tf, ctl_locase_next);
|
||
cur++;
|
||
break;
|
||
|
||
case 'U':
|
||
/* Turn the replacement to uppercase until a `\L' or `\E'
|
||
is found, */
|
||
add_case_ctl_segment (tf, ctl_upcase);
|
||
cur++;
|
||
break;
|
||
|
||
case 'u':
|
||
/* Turn the next character to uppercase, */
|
||
add_case_ctl_segment (tf, ctl_upcase_next);
|
||
cur++;
|
||
break;
|
||
|
||
case 'E':
|
||
/* Stop case conversion started by `\L' or `\U'. */
|
||
add_case_ctl_segment (tf, ctl_stop);
|
||
cur++;
|
||
break;
|
||
|
||
default:
|
||
/* Try to be nice */
|
||
{
|
||
char buf[2];
|
||
buf[0] = '\\';
|
||
buf[1] = *cur;
|
||
add_literal_segment (tf, buf, buf + 2);
|
||
}
|
||
cur++;
|
||
break;
|
||
}
|
||
beg = cur;
|
||
}
|
||
else if (*cur == '&')
|
||
{
|
||
add_literal_segment (tf, beg, cur);
|
||
add_backref_segment (tf, 0);
|
||
beg = ++cur;
|
||
}
|
||
else
|
||
cur++;
|
||
}
|
||
add_literal_segment (tf, beg, cur);
|
||
if (transform_err (tf))
|
||
{
|
||
*endp = expr + i + (beg - str);
|
||
free (str);
|
||
return transform_err (tf);
|
||
}
|
||
*endp = p;
|
||
return 0;
|
||
}
|
||
|
||
int
|
||
gray_set_transform_expr (const char *expr)
|
||
{
|
||
while (*expr)
|
||
{
|
||
int rc = parse_transform_expr (expr, &expr);
|
||
if (rc != PAM_SUCCESS)
|
||
{
|
||
gray_free_transform_expr ();
|
||
return rc;
|
||
}
|
||
}
|
||
return PAM_SUCCESS;
|
||
}
|
||
|
||
void
|
||
gray_free_transform_expr (void)
|
||
{
|
||
while (transform_head)
|
||
{
|
||
struct transform *next = transform_head->next;
|
||
free_transform (transform_head);
|
||
transform_head = next;
|
||
}
|
||
transform_tail = NULL;
|
||
free (case_ctl_buffer);
|
||
case_ctl_buffer = NULL;
|
||
case_ctl_bufsize = 0;
|
||
}
|
||
|
||
/* Run case conversion specified by CASE_CTL on array PTR of SIZE
|
||
characters. Returns pointer to statically allocated storage. */
|
||
static char *
|
||
run_case_conv (enum case_ctl_type case_ctl, char *ptr, size_t size)
|
||
{
|
||
char *p;
|
||
|
||
if (case_ctl_bufsize < size)
|
||
{
|
||
p = realloc (case_ctl_buffer, size);
|
||
if (!p)
|
||
return NULL;
|
||
case_ctl_buffer = p;
|
||
case_ctl_bufsize = size;
|
||
}
|
||
memcpy (case_ctl_buffer, ptr, size);
|
||
switch (case_ctl)
|
||
{
|
||
case ctl_upcase_next:
|
||
case_ctl_buffer[0] = toupper (case_ctl_buffer[0]);
|
||
break;
|
||
|
||
case ctl_locase_next:
|
||
case_ctl_buffer[0] = tolower (case_ctl_buffer[0]);
|
||
break;
|
||
|
||
case ctl_upcase:
|
||
for (p = case_ctl_buffer; p < case_ctl_buffer + size; p++)
|
||
*p = toupper (*p);
|
||
break;
|
||
|
||
case ctl_locase:
|
||
for (p = case_ctl_buffer; p < case_ctl_buffer + size; p++)
|
||
*p = tolower (*p);
|
||
break;
|
||
|
||
case ctl_stop:
|
||
break;
|
||
}
|
||
return case_ctl_buffer;
|
||
}
|
||
|
||
|
||
static int
|
||
_single_transform_name_to_slist (struct transform *tf, gray_slist_t slist,
|
||
char *input)
|
||
{
|
||
regmatch_t *rmp;
|
||
int rc;
|
||
size_t nmatches = 0;
|
||
enum case_ctl_type case_ctl = ctl_stop, /* Current case conversion op */
|
||
save_ctl = ctl_stop; /* Saved case_ctl for \u and \l */
|
||
|
||
/* Reset case conversion after a single-char operation */
|
||
#define CASE_CTL_RESET() if (case_ctl == ctl_upcase_next \
|
||
|| case_ctl == ctl_locase_next) \
|
||
{ \
|
||
case_ctl = save_ctl; \
|
||
save_ctl = ctl_stop; \
|
||
}
|
||
|
||
rmp = malloc ((tf->regex.re_nsub + 1) * sizeof (*rmp));
|
||
if (!rmp)
|
||
return errno;
|
||
while (*input)
|
||
{
|
||
size_t disp;
|
||
char *ptr;
|
||
|
||
rc = regexec (&tf->regex, input, tf->regex.re_nsub + 1, rmp, 0);
|
||
|
||
if (rc == 0)
|
||
{
|
||
struct replace_segm *segm;
|
||
|
||
disp = rmp[0].rm_eo;
|
||
|
||
nmatches++;
|
||
if (tf->match_number && nmatches < tf->match_number)
|
||
{
|
||
gray_slist_append (slist, input, disp);
|
||
input += disp;
|
||
continue;
|
||
}
|
||
|
||
if (rmp[0].rm_so)
|
||
gray_slist_append (slist, input, rmp[0].rm_so);
|
||
|
||
for (segm = tf->repl_head; segm; segm = segm->next)
|
||
{
|
||
switch (segm->type)
|
||
{
|
||
case segm_literal: /* Literal segment */
|
||
if (case_ctl == ctl_stop)
|
||
ptr = segm->v.literal.ptr;
|
||
else
|
||
{
|
||
ptr = run_case_conv (case_ctl,
|
||
segm->v.literal.ptr,
|
||
segm->v.literal.size);
|
||
if (!ptr)
|
||
return errno;
|
||
CASE_CTL_RESET();
|
||
}
|
||
gray_slist_append (slist, ptr, segm->v.literal.size);
|
||
break;
|
||
|
||
case segm_backref: /* Back-reference segment */
|
||
if (rmp[segm->v.ref].rm_so != -1
|
||
&& rmp[segm->v.ref].rm_eo != -1)
|
||
{
|
||
size_t size = rmp[segm->v.ref].rm_eo
|
||
- rmp[segm->v.ref].rm_so;
|
||
ptr = input + rmp[segm->v.ref].rm_so;
|
||
if (case_ctl != ctl_stop)
|
||
{
|
||
ptr = run_case_conv (case_ctl, ptr, size);
|
||
if (!ptr)
|
||
return errno;
|
||
CASE_CTL_RESET();
|
||
}
|
||
|
||
gray_slist_append (slist, ptr, size);
|
||
}
|
||
break;
|
||
|
||
case segm_case_ctl:
|
||
switch (segm->v.ctl)
|
||
{
|
||
case ctl_upcase_next:
|
||
case ctl_locase_next:
|
||
switch (save_ctl)
|
||
{
|
||
case ctl_stop:
|
||
case ctl_upcase:
|
||
case ctl_locase:
|
||
save_ctl = case_ctl;
|
||
default:
|
||
break;
|
||
}
|
||
/*FALL THROUGH*/
|
||
|
||
case ctl_upcase:
|
||
case ctl_locase:
|
||
case ctl_stop:
|
||
case_ctl = segm->v.ctl;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
disp = strlen (input);
|
||
gray_slist_append (slist, input, disp);
|
||
}
|
||
|
||
input += disp;
|
||
|
||
if (tf->transform_type == transform_first)
|
||
{
|
||
gray_slist_append (slist, input, strlen (input));
|
||
break;
|
||
}
|
||
}
|
||
|
||
gray_slist_append_char (slist, 0);
|
||
free (rmp);
|
||
return gray_slist_err (slist);
|
||
}
|
||
|
||
int
|
||
gray_transform_name_to_slist (gray_slist_t slist, char *input, char **output)
|
||
{
|
||
if (transform_head)
|
||
{
|
||
struct transform *tf;
|
||
for (tf = transform_head; tf; tf = tf->next)
|
||
{
|
||
int rc = _single_transform_name_to_slist (tf, slist, input);
|
||
if (rc)
|
||
return errno_to_pam(rc);
|
||
input = gray_slist_finish (slist);
|
||
if (!input)
|
||
return errno_to_pam(errno);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
gray_slist_append(slist, input, strlen(input) + 1);
|
||
input = gray_slist_finish (slist);
|
||
if (!input)
|
||
return errno_to_pam(errno);
|
||
}
|
||
*output = input;
|
||
|
||
return PAM_SUCCESS;
|
||
}
|
||
|
||
|