diff options
| -rw-r--r-- | source3/lib/util_path.c | 133 | ||||
| -rw-r--r-- | source3/lib/util_path.h | 1 |
2 files changed, 134 insertions, 0 deletions
diff --git a/source3/lib/util_path.c b/source3/lib/util_path.c index 509ba5ff727..cbad2e15d48 100644 --- a/source3/lib/util_path.c +++ b/source3/lib/util_path.c @@ -93,3 +93,136 @@ char *cache_path(const char *name) { return xx_path(name, lp_cache_directory()); } + +/** + * @brief Removes any invalid path components in an absolute POSIX path. + * + * @param ctx Talloc context to return string. + * + * @param abs_path Absolute path string to process. + * + * @retval Pointer to a talloc'ed string containing the absolute full path. + **/ + +char *canonicalize_absolute_path(TALLOC_CTX *ctx, const char *abs_path) +{ + char *destname; + char *d; + const char *s = abs_path; + bool start_of_name_component = true; + + /* Allocate for strlen + '\0' + possible leading '/' */ + destname = (char *)talloc_size(ctx, strlen(abs_path) + 2); + if (destname == NULL) { + return NULL; + } + d = destname; + + *d++ = '/'; /* Always start with root. */ + + while (*s) { + if (*s == '/') { + /* Eat multiple '/' */ + while (*s == '/') { + s++; + } + if ((d > destname + 1) && (*s != '\0')) { + *d++ = '/'; + } + start_of_name_component = true; + continue; + } + + if (start_of_name_component) { + if ((s[0] == '.') && (s[1] == '.') && + (s[2] == '/' || s[2] == '\0')) { + /* Uh oh - "/../" or "/..\0" ! */ + + /* Go past the ../ or .. */ + if (s[2] == '/') { + s += 3; + } else { + s += 2; /* Go past the .. */ + } + + /* If we just added a '/' - delete it */ + if ((d > destname) && (*(d-1) == '/')) { + *(d-1) = '\0'; + d--; + } + + /* + * Are we at the start ? + * Can't go back further if so. + */ + if (d <= destname) { + *d++ = '/'; /* Can't delete root */ + continue; + } + /* Go back one level... */ + /* + * Decrement d first as d points to + * the *next* char to write into. + */ + for (d--; d > destname; d--) { + if (*d == '/') { + break; + } + } + /* + * We're still at the start of a name + * component, just the previous one. + */ + continue; + } else if ((s[0] == '.') && + ((s[1] == '\0') || s[1] == '/')) { + /* + * Component of pathname can't be "." only. + * Skip the '.' . + */ + if (s[1] == '/') { + s += 2; + } else { + s++; + } + continue; + } + } + + if (!(*s & 0x80)) { + *d++ = *s++; + } else { + size_t siz; + /* Get the size of the next MB character. */ + next_codepoint(s,&siz); + switch(siz) { + case 5: + *d++ = *s++; + /*fall through*/ + case 4: + *d++ = *s++; + /*fall through*/ + case 3: + *d++ = *s++; + /*fall through*/ + case 2: + *d++ = *s++; + /*fall through*/ + case 1: + *d++ = *s++; + break; + default: + break; + } + } + start_of_name_component = false; + } + *d = '\0'; + + /* And must not end in '/' */ + if (d > destname + 1 && (*(d-1) == '/')) { + *(d-1) = '\0'; + } + + return destname; +} diff --git a/source3/lib/util_path.h b/source3/lib/util_path.h index 118a4bed524..16e27926084 100644 --- a/source3/lib/util_path.h +++ b/source3/lib/util_path.h @@ -27,5 +27,6 @@ char *lock_path(const char *name); char *state_path(const char *name); char *cache_path(const char *name); +char *canonicalize_absolute_path(TALLOC_CTX *ctx, const char *abs_path); #endif |