Annotation of 3BSD/cmd/net/mmail.c, revision 1.1.1.1

1.1       root        1: # include "defs.h"
                      2: /*
                      3:    Mmail is a berkeley network internal command.
                      4:    It is executed locally by the mwrite command,
                      5:    and from a remote machine by the sendberkmail command.
                      6:    Its purpose is to send mail to a user on this
                      7:    machine using the system mail program.
                      8: 
                      9: Archaic Usage:
                     10: 
                     11:    mmail [-commandsent -timesent] fromuser frommach touser
                     12: 
                     13: Correct Usage:
                     14:    mmail [-c commandsent] [-e timesent] [-f fromaddress] [-t toaddress] 
                     15:        [-h hopcnt] [-r rc] [-z]
                     16: 
                     17:    The mwrite command uses all the options.
                     18:    The sendberkmail command does not use the commandsend, timesent and rc 
                     19:    options.
                     20:    Timesent is time in seconds since 1901 in decimal, as returned by time().
                     21:    Frommach is a multi-character name, not a single letter.
                     22:    Rc is the return code (exit code>>8) of the command.
                     23: 
                     24: Assumptions about the system mail command:
                     25: 1. We assume there is an optional argument "-r" which can be added to mail.
                     26:    Mail argument format (two choices):
                     27: 
                     28:    (ROPTION)
                     29:                mail -f fromaddress toaddress
                     30:        which becomes mail from "fromaddress" instead of "network".
                     31: 
                     32:    (ROPTION2)
                     33:                mail -r frommach fromuser toaddress
                     34:        which becomes mail from "fromach:fromuser" instead of "network".
                     35: 
                     36:    ROPTION is to be preferred.
                     37: 
                     38: 2. We assume that mail accepts the "-h hopcnt" flag, and passes it thru
                     39:    unchanged to the sendberkmail program.  The hopcnt is incremented everytime
                     40:    it passes thru mmail, so inifinite mail forwarding is detected.
                     41:    Since both the from and to addresses cycle, it there is infinite looping
                     42:    we simply mail to root to that effect and throw away the mail.
                     43: 
                     44: 
                     45:    If this argument scheme looks flakey it is because I screwed up
                     46:    in the argument design.  With the network now up to 10 machines,
                     47:    I can't add another parameter to the internal commands of the network
                     48:    like mmail and mwrite.  If I had used labeled parms instead of
                     49:    positional parms, I would be able to add more options/info
                     50:    without having to recompile all code...
                     51: 
                     52:    exit codes:
                     53:        normally returns the exit code from the mail program
                     54:        returns 101 if unable to exec the mail program
                     55:        returns 102 if infinite mail forwarding loop is detected.
                     56: 
                     57:    NUID is the value returned from getuid for "network" account.
                     58: */
                     59: main(argc,argv)
                     60:   char **argv; {
                     61:        int pip[2], n, ret, i, uid, roption = 0, hopcnt = 0, pid;
                     62:        char *sargv[20], *cmdstr=NULL, buf[BUFSIZ], *timestr, fromaddress[BUFSIZ];
                     63:        char toaddress[BUFSIZ], src[20], snFrom[BUFSIZ], snto[BUFSIZ], mchFrom, mchto,
                     64:                *sn, stemp[BUFSIZ], fisresponse = 0;
                     65:        long timesent = TIMEBASE, el;
                     66: 
                     67:        debugflg = DBV;
                     68:        src[0] = 0;
                     69: 
                     70:        /* parse old format positional parms */
                     71:        if(argv[1][0] == '-'){
                     72:                cmdstr = argv[1] + 1;
                     73:                timesent = atol(argv[2] + 1);
                     74:                sprintf(fromaddress,"%s:%s",argv[4],argv[3]);
                     75:                strcpy(toaddress,argv[5]);
                     76:        }
                     77:        else {
                     78:                sprintf(fromaddress,"%s:%s",argv[2],argv[1]);
                     79:                strcpy(toaddress,argv[3]);
                     80:        }
                     81:        argv[argc] = 0;
                     82: 
                     83:        /* parse labeled parameters */
                     84:        /*  prob because of -cmd in arg1 and arg2 */
                     85:        for(i = 1; i < argc; i++){
                     86:                if(argv[i][0] == '-' && argv[i][2] == 0)
                     87:                switch(argv[i][1]){
                     88:                case 'f': 
                     89:                        strcpy(fromaddress,argv[++i]);
                     90:                        break;
                     91:                case 'c': 
                     92:                        cmdstr = argv[++i];
                     93:                        break;
                     94:                case 'e':
                     95:                        timesent = atol(argv[++i]);
                     96:                        break;
                     97:                case 't':
                     98:                        strcpy(toaddress,argv[++i]);
                     99:                        break;
                    100:                case 'h':
                    101:                        hopcnt = atoi(argv[++i]);
                    102:                        break;
                    103:                case 'r':
                    104:                        strcpy(src,argv[++i]);
                    105:                        break;
                    106:                case 'z':
                    107:                        fisresponse++;
                    108:                        break;
                    109:                /* it is important there be no error if an unknown
                    110:                   flag is encountered */
                    111:                }
                    112:        }
                    113:        mchFrom = MchSFromAddr(snFrom,fromaddress);
                    114: 
                    115:        /* compute time send */
                    116:        timestr = ctime(&timesent);
                    117:        timestr[strlen(timestr) - 6] = 0;
                    118:        el = gettime() - timesent;
                    119: 
                    120: # ifdef ROPTION
                    121:        /* only use roption if super-user or "network" */
                    122: /*
                    123:        uid = getuid();
                    124:        uid = uidmask(uid);
                    125:        if(uid == SUPERUSER || uid == NUID)roption++;
                    126: */
                    127:        /* or if mail is to the same user who is sending it */
                    128: /*
                    129:        sn = SnCurrent();
                    130:        if(sn != NULL){
                    131:                stemp[0] = 0;
                    132:                mchfrom = MchSFromAddr(stemp,fromaddress);
                    133:                if(strcmp(stemp,????) == 0)roption++;
                    134:        }
                    135:        uid = geteuid();
                    136:        uid = uidmask(uid);
                    137:        if(uid == SUPERUSER || uid == NUID)roption++;
                    138: */
                    139:        roption++;
                    140: # endif
                    141: 
                    142: # ifdef ROPTION2
                    143:        /* only use roption if super-user or "network" */
                    144:        uid = getuid();
                    145:        uid = uidmask(uid);
                    146:        if(uid == SUPERUSER || uid == NUID)roption++;
                    147:        /* or if mail is to the same user who is sending it */
                    148:        /* disabled since mail must accept this  and it does not now */
                    149:        /* if(strcmp(SnCurrent(),argv[3]) == 0)roption++; */
                    150:        uid = geteuid();
                    151:        uid = uidmask(uid);
                    152:        if(uid == SUPERUSER || uid == NUID)roption++;
                    153: # endif
                    154: 
                    155:        /* check the hopcnt */
                    156:        hopcnt++;
                    157:        if(hopcnt > MAXHOPS)hopcnterr(toaddress, hopcnt);
                    158: 
                    159:        /* analyze the dest, if local, strip off mach name, otherwise ok */
                    160:        mchto = MchSFromAddr(snto,toaddress);
                    161:        if(mchto == local)strcpy(toaddress,snto);
                    162: 
                    163:        /* add the hopcnt here */
                    164:        if(roption){
                    165:                sargv[1] = "-r";
                    166: # ifdef ROPTION2
                    167:                sargv[2] = longname(mchFrom);
                    168:                sargv[3] = snFrom;
                    169:                sargv[4] = toaddress;
                    170:                sargv[5] = 0;
                    171: # endif
                    172: # ifdef ROPTION
                    173:                sargv[2] = fromaddress;
                    174:                sargv[3] = toaddress;
                    175:                sargv[4] = 0;
                    176: # endif
                    177:                }
                    178:        else {
                    179:                sargv[1] = toaddress;
                    180:                sargv[2] = 0;
                    181:                }
                    182:        sargv[0] = "mail";
                    183:        pipe(pip);
                    184:        while((pid = fork()) == -1)sleep(2);
                    185:        if(pid == 0){
                    186:                close(pip[1]);
                    187:                close(0);
                    188:                dup(pip[0]);
                    189:                /* by convention, SYSMAIL1 may forward this mail
                    190:                   and response messages shouldn't be forwarded */
                    191:                if(!fisresponse)
                    192:                        execv(SYSMAIL1, sargv);
                    193:                execv(SYSMAIL2, sargv);
                    194:                execv(SYSMAIL3, sargv);
                    195:                execv(SYSMAIL4, sargv);
                    196:                exit(101);
                    197:                /* mexecv is not used because it gives a diagnostic */
                    198:                }
                    199:        close(pip[0]);
                    200:        close(1);
                    201:        dup(pip[1]);
                    202:        if(!roption)
                    203:                printf("(from %s)\n",fromaddress);
                    204:        if(cmdstr != NULL){
                    205:                if(src[0] != 0)sprintf(stemp,", R: %s", src);
                    206:                else stemp[0] = 0;
                    207:                printf("(command: %s%s, sent %s, took %s)\n",
                    208:                        cmdstr,stemp,timestr,comptime(el));
                    209:        }
                    210:        fflush(stdout);
                    211:        while((n = read(0,buf,BUFSIZ)) > 0)
                    212:                write(pip[1],buf,n);
                    213:        close(pip[1]);
                    214:        close(1);
                    215:        wait(&ret);
                    216:        ret >>= 8;
                    217:        if(ret != 0)
                    218:                fprintf(stderr,
                    219:                "Non-zero return code (%d) from the mail program.\n",ret);
                    220:        exit(ret);
                    221:        }
                    222: /*
                    223:        hopcnterr()
                    224: 
                    225:        there appears to be infinite mail forwarding -
                    226:        as detected by the hop count.  Mail to root and give up.
                    227:        Both the from and to addresses are cycling, so mail 
                    228:        can't be sent there.
                    229: */
                    230: hopcnterr(toaddress,hopcnt)
                    231:        char *toaddress;
                    232:        int hopcnt;
                    233: {
                    234:        char cmdstr[BUFSIZ];
                    235:        int rcode;
                    236:        sprintf(cmdstr,"echo infinite mail loop for %s hops %d | mail root",
                    237:                toaddress,hopcnt);
                    238:        rcode = system(cmdstr);
                    239:        exit(102);
                    240:        /*UNREACHED*/
                    241: }

unix.superglobalmegacorp.com

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.