diff options
Diffstat (limited to 'Modules/getpath.c')
| -rw-r--r-- | Modules/getpath.c | 57 |
1 files changed, 41 insertions, 16 deletions
diff --git a/Modules/getpath.c b/Modules/getpath.c index 7d9a961..276e938 100644 --- a/Modules/getpath.c +++ b/Modules/getpath.c @@ -98,7 +98,7 @@ */ #ifndef VERSION -#define VERSION "1.5" +#define VERSION "2.0" #endif #ifndef VPATH @@ -122,7 +122,7 @@ #ifndef LANDMARK #define LANDMARK "os.py" #endif - + static char prefix[MAXPATHLEN+1]; static char exec_prefix[MAXPATHLEN+1]; static char progpath[MAXPATHLEN+1]; @@ -201,6 +201,11 @@ isdir(char *filename) /* Is directory */ } +/* joinpath requires that any buffer argument passed to it has at + least MAXPATHLEN + 1 bytes allocated. If this requirement is met, + it guarantees that it will never overflow the buffer. If stuff + is too long, buffer will contain a truncated copy of stuff. +*/ static void joinpath(char *buffer, char *stuff) { @@ -219,6 +224,10 @@ joinpath(char *buffer, char *stuff) buffer[n+k] = '\0'; } +/* init_path_from_argv0 requirs that path be allocated at least + MAXPATHLEN + 1 bytes and that argv0_path be no more than MAXPATHLEN + bytes. +*/ static void init_path_from_argv0(char *path, char *argv0_path) { @@ -237,6 +246,9 @@ init_path_from_argv0(char *path, char *argv0_path) } } +/* search_for_prefix requires that argv0_path be no more than MAXPATHLEN + bytes long. +*/ static int search_for_prefix(char *argv0_path, char *home) { @@ -246,7 +258,7 @@ search_for_prefix(char *argv0_path, char *home) /* If PYTHONHOME is set, we believe it unconditionally */ if (home) { char *delim; - strcpy(prefix, home); + strncpy(prefix, home, MAXPATHLEN); delim = strchr(prefix, DELIM); if (delim) *delim = '\0'; @@ -293,7 +305,7 @@ search_for_prefix(char *argv0_path, char *home) } while (prefix[0]); /* Look at configure's PREFIX */ - strcpy(prefix, PREFIX); + strncpy(prefix, PREFIX, MAXPATHLEN); joinpath(prefix, lib_python); joinpath(prefix, LANDMARK); if (ismodule(prefix)) @@ -304,6 +316,9 @@ search_for_prefix(char *argv0_path, char *home) } +/* search_for_exec_prefix requires that argv0_path be no more than + MAXPATHLEN bytes long. +*/ static int search_for_exec_prefix(char *argv0_path, char *home) { @@ -314,9 +329,9 @@ search_for_exec_prefix(char *argv0_path, char *home) char *delim; delim = strchr(home, DELIM); if (delim) - strcpy(exec_prefix, delim+1); + strncpy(exec_prefix, delim+1, MAXPATHLEN); else - strcpy(exec_prefix, home); + strncpy(exec_prefix, home, MAXPATHLEN); joinpath(exec_prefix, lib_python); joinpath(exec_prefix, "lib-dynload"); return 1; @@ -343,7 +358,7 @@ search_for_exec_prefix(char *argv0_path, char *home) } while (exec_prefix[0]); /* Look at configure's EXEC_PREFIX */ - strcpy(exec_prefix, EXEC_PREFIX); + strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); joinpath(exec_prefix, lib_python); joinpath(exec_prefix, "lib-dynload"); if (isdir(exec_prefix)) @@ -377,6 +392,7 @@ calculate_path(void) #endif #ifdef WITH_NEXT_FRAMEWORK + /* XXX Need to check this code for buffer overflows */ pythonModule = NSModuleForSymbol(NSLookupAndBindSymbol("_Py_Initialize")); /* Use dylib functions to find out where the framework was loaded from */ buf = NSLibraryNameForModule(pythonModule); @@ -393,7 +409,7 @@ calculate_path(void) #endif /* Initialize this dynamically for K&R C */ - sprintf(lib_python, "lib/python%s", VERSION); + sprintf(lib_python, "lib/python%.9s", VERSION); /* If there is no slash in the argv0 path, then we have to * assume python is on the user's $PATH, since there's no @@ -401,18 +417,22 @@ calculate_path(void) * $PATH isn't exported, you lose. */ if (strchr(prog, SEP)) - strcpy(progpath, prog); + strncpy(progpath, prog, MAXPATHLEN); else if (path) { + int bufspace = MAXPATHLEN; while (1) { char *delim = strchr(path, DELIM); if (delim) { size_t len = delim - path; + if (len > bufspace) + len = bufspace; strncpy(progpath, path, len); *(progpath + len) = '\0'; + bufspace -= len; } else - strcpy(progpath, path); + strncpy(progpath, path, bufspace); joinpath(progpath, prog); if (isxfile(progpath)) @@ -431,7 +451,7 @@ calculate_path(void) } #endif - strcpy(argv0_path, progpath); + strncpy(argv0_path, progpath, MAXPATHLEN); #if HAVE_READLINK { @@ -441,7 +461,9 @@ calculate_path(void) /* It's not null terminated! */ tmpbuffer[linklen] = '\0'; if (tmpbuffer[0] == SEP) - strcpy(argv0_path, tmpbuffer); + /* tmpbuffer should never be longer than MAXPATHLEN, + but extra check does not hurt */ + strncpy(argv0_path, tmpbuffer, MAXPATHLEN); else { /* Interpret relative to progpath */ reduce(argv0_path); @@ -453,12 +475,15 @@ calculate_path(void) #endif /* HAVE_READLINK */ reduce(argv0_path); + /* At this point, argv0_path is guaranteed to be less than + MAXPATHLEN bytes long. + */ if (!(pfound = search_for_prefix(argv0_path, home))) { if (!Py_FrozenFlag) fprintf(stderr, "Could not find platform independent libraries <prefix>\n"); - strcpy(prefix, PREFIX); + strncpy(prefix, PREFIX, MAXPATHLEN); joinpath(prefix, lib_python); } else @@ -468,7 +493,7 @@ calculate_path(void) if (!Py_FrozenFlag) fprintf(stderr, "Could not find platform dependent libraries <exec_prefix>\n"); - strcpy(exec_prefix, EXEC_PREFIX); + strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); joinpath(exec_prefix, "lib/lib-dynload"); } /* If we found EXEC_PREFIX do *not* reduce it! (Yet.) */ @@ -565,7 +590,7 @@ calculate_path(void) reduce(prefix); } else - strcpy(prefix, PREFIX); + strncpy(prefix, PREFIX, MAXPATHLEN); if (efound > 0) { reduce(exec_prefix); @@ -573,7 +598,7 @@ calculate_path(void) reduce(exec_prefix); } else - strcpy(exec_prefix, EXEC_PREFIX); + strncpy(exec_prefix, EXEC_PREFIX, MAXPATHLEN); } |