Mercurial > hg > toybox
view lib/password.c @ 818:264b9da809df
Simplify license text, as mentioned on the mailing list.
Reasoning: it was never my intent to require anybody to copy license
text into another project if they cut and pasted something out of
toybox. The "permission for any purpose" is as close to public domain
as you can get in our current screwed up legal system without making
people uncomfortable the _other_ way. (Besides, my initial reading of
that was "all copies of the source code" but that's not what it says,
and somebody pointed out that Android has "show license text" options
because paranoid lawyers think that sort of thing applies to the BINARY
version, which is nuts.)
author | Rob Landley <rob@landley.net> |
---|---|
date | Thu, 14 Mar 2013 09:02:37 -0500 |
parents | 786841fdb1e0 |
children | 77235d224b1d |
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line source
/* pwdutils.c - password read/update helper functions. * * Copyright 2012 Ashwini Kumar <ak.ashwini@gmail.com> */ #include "toys.h" #include <time.h> int read_password(char * buff, int buflen, char* mesg) { int i = 0; struct termios termio, oldtermio; tcgetattr(0, &oldtermio); tcflush(0, TCIFLUSH); termio = oldtermio; termio.c_iflag &= ~(IUCLC|IXON|IXOFF|IXANY); termio.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|TOSTOP); tcsetattr(0, TCSANOW, &termio); fputs(mesg, stdout); fflush(stdout); while (1) { int ret = read(0, &buff[i], 1); if ( ret < 0 ) { buff[0] = 0; tcsetattr(0, TCSANOW, &oldtermio); return 1; } else if (ret == 0 || buff[i] == '\n' || buff[i] == '\r' || buflen == i+1) { buff[i] = '\0'; break; } i++; } tcsetattr(0, TCSANOW, &oldtermio); puts(""); fflush(stdout); return 0; } static char *get_nextcolon(const char *line, char delim) { char *current_ptr = NULL; if((current_ptr = strchr(line, ':')) == NULL) error_exit("Invalid Entry\n"); return current_ptr; } int update_password(char *filename, char* username, char* encrypted) { char *filenamesfx = NULL, *namesfx = NULL; char *shadow = NULL, *sfx = NULL; FILE *exfp, *newfp; int ret = -1; //fail struct flock lock; char *line = NULL; shadow = strstr(filename, "shadow"); filenamesfx = xmsprintf("%s+", filename); sfx = strchr(filenamesfx, '+'); exfp = fopen(filename, "r+"); if(!exfp) { perror_msg("Couldn't open file %s",filename); goto free_storage; } *sfx = '-'; ret = unlink(filenamesfx); ret = link(filename, filenamesfx); if(ret < 0) error_msg("can't create backup file"); *sfx = '+'; lock.l_type = F_WRLCK; lock.l_whence = SEEK_SET; lock.l_start = 0; lock.l_len = 0; ret = fcntl(fileno(exfp), F_SETLK, &lock); if(ret < 0) perror_msg("Couldn't lock file %s",filename); lock.l_type = F_UNLCK; //unlocking at a later stage newfp = fopen(filenamesfx, "w+"); if(!newfp) { error_msg("couldn't open file for writing"); ret = -1; fclose(exfp); goto free_storage; } ret = 0; namesfx = xmsprintf("%s:",username); while((line = get_line(fileno(exfp))) != NULL) { if(strncmp(line, namesfx, strlen(namesfx)) != 0) fprintf(newfp, "%s\n", line); else { char *current_ptr = NULL; fprintf(newfp, "%s%s:",namesfx,encrypted); current_ptr = get_nextcolon(line, ':'); //past username current_ptr++; //past colon ':' after username current_ptr = get_nextcolon(current_ptr, ':'); //past passwd current_ptr++; //past colon ':' after passwd if(shadow) { fprintf(newfp, "%u:",(unsigned)(time(NULL))/(24*60*60)); current_ptr = get_nextcolon(current_ptr, ':'); current_ptr++; //past time stamp colon. fprintf(newfp, "%s\n",current_ptr); } else fprintf(newfp, "%s\n",current_ptr); } free(line); } free(namesfx); fcntl(fileno(exfp), F_SETLK, &lock); fclose(exfp); errno = 0; fflush(newfp); fsync(fileno(newfp)); fclose(newfp); rename(filenamesfx, filename); if(errno) { perror_msg("File Writing/Saving failed: "); unlink(filenamesfx); ret = -1; } free_storage: free(filenamesfx); return ret; }