Commit | Line | Data |
---|---|---|
4a31bc6f | 1 | #ifndef lint |
4ca10280 | 2 | static char sccsid[] = "@(#)rsh.c 4.8 83/06/10"; |
4a31bc6f BJ |
3 | #endif |
4 | ||
4a31bc6f BJ |
5 | #include <sys/types.h> |
6 | #include <sys/socket.h> | |
e7d6d17a | 7 | #include <sys/ioctl.h> |
4a31bc6f | 8 | #include <sys/file.h> |
e7d6d17a SL |
9 | |
10 | #include <netinet/in.h> | |
11 | ||
12 | #include <stdio.h> | |
4a31bc6f BJ |
13 | #include <errno.h> |
14 | #include <signal.h> | |
4a31bc6f | 15 | #include <pwd.h> |
e1e93bd3 | 16 | #include <netdb.h> |
4a31bc6f BJ |
17 | |
18 | /* | |
19 | * rsh - remote shell | |
20 | */ | |
21 | /* VARARGS */ | |
22 | int error(); | |
23 | char *index(), *rindex(), *malloc(), *getpass(), *sprintf(), *strcpy(); | |
24 | ||
25 | struct passwd *getpwuid(); | |
26 | ||
27 | int errno; | |
28 | int options; | |
29 | int rfd2; | |
30 | int sendsig(); | |
31 | ||
4ca10280 SL |
32 | #define mask(s) (1 << ((s) - 1)) |
33 | ||
4a31bc6f BJ |
34 | main(argc, argv0) |
35 | int argc; | |
36 | char **argv0; | |
37 | { | |
38 | int rem, pid; | |
39 | char *host, *cp, **ap, buf[BUFSIZ], *args, **argv = argv0, *user = 0; | |
40 | register int cc; | |
41 | int asrsh = 0; | |
42 | struct passwd *pwd; | |
43 | int readfrom, ready; | |
44 | int one = 1; | |
e1e93bd3 | 45 | struct servent *sp; |
4ca10280 | 46 | int omask; |
4a31bc6f BJ |
47 | |
48 | host = rindex(argv[0], '/'); | |
49 | if (host) | |
50 | host++; | |
51 | else | |
52 | host = argv[0]; | |
53 | argv++, --argc; | |
54 | if (!strcmp(host, "rsh")) { | |
55 | host = *argv++, --argc; | |
56 | asrsh = 1; | |
57 | } | |
58 | another: | |
4659bf8e | 59 | if (argc > 0 && !strcmp(*argv, "-l")) { |
4a31bc6f BJ |
60 | argv++, argc--; |
61 | if (argc > 0) | |
62 | user = *argv++, argc--; | |
63 | goto another; | |
64 | } | |
4659bf8e | 65 | if (argc > 0 && !strcmp(*argv, "-n")) { |
4a31bc6f BJ |
66 | argv++, argc--; |
67 | (void) close(0); | |
68 | (void) open("/dev/null", 0); | |
69 | goto another; | |
70 | } | |
4659bf8e | 71 | if (argc > 0 && !strcmp(*argv, "-d")) { |
4a31bc6f BJ |
72 | argv++, argc--; |
73 | options |= SO_DEBUG; | |
74 | goto another; | |
75 | } | |
0f09f657 CL |
76 | /* |
77 | * Ignore the -e flag to allow aliases with rlogin | |
78 | * to work | |
79 | */ | |
4659bf8e | 80 | if (argc > 0 && !strncmp(*argv, "-e", 2)) { |
0f09f657 CL |
81 | argv++, argc--; |
82 | goto another; | |
83 | } | |
4a31bc6f BJ |
84 | if (host == 0) |
85 | goto usage; | |
86 | if (argv[0] == 0) { | |
87 | if (asrsh) | |
88 | *argv0 = "rlogin"; | |
89 | execv("/usr/ucb/rlogin", argv0); | |
90 | perror("/usr/ucb/rlogin"); | |
91 | exit(1); | |
92 | } | |
93 | pwd = getpwuid(getuid()); | |
94 | if (pwd == 0) { | |
95 | fprintf(stderr, "who are you?\n"); | |
96 | exit(1); | |
97 | } | |
98 | cc = 0; | |
99 | for (ap = argv; *ap; ap++) | |
100 | cc += strlen(*ap) + 1; | |
101 | cp = args = malloc(cc); | |
102 | for (ap = argv; *ap; ap++) { | |
103 | (void) strcpy(cp, *ap); | |
104 | while (*cp) | |
105 | cp++; | |
106 | if (ap[1]) | |
107 | *cp++ = ' '; | |
108 | } | |
e1e93bd3 SL |
109 | sp = getservbyname("shell", "tcp"); |
110 | if (sp == 0) { | |
111 | fprintf(stderr, "rsh: shell/tcp: unknown service\n"); | |
112 | exit(1); | |
113 | } | |
114 | rem = rcmd(&host, sp->s_port, pwd->pw_name, | |
4a31bc6f BJ |
115 | user ? user : pwd->pw_name, args, &rfd2); |
116 | if (rem < 0) | |
117 | exit(1); | |
30b254da SL |
118 | if (rfd2 < 0) { |
119 | fprintf(stderr, "rsh: can't establish stderr\n"); | |
120 | exit(2); | |
121 | } | |
122 | if (options & SO_DEBUG) { | |
123 | if (setsockopt(rem, SOL_SOCKET, SO_DEBUG, 0, 0) < 0) | |
124 | perror("setsockopt (stdin)"); | |
125 | if (setsockopt(rfd2, SOL_SOCKET, SO_DEBUG, 0, 0) < 0) | |
126 | perror("setsockopt (stderr)"); | |
127 | } | |
4a31bc6f | 128 | (void) setuid(getuid()); |
4ca10280 SL |
129 | omask = sigblock(mask(SIGINT)|mask(SIGQUIT)|mask(SIGTERM)); |
130 | signal(SIGINT, sendsig); | |
131 | signal(SIGQUIT, sendsig); | |
132 | signal(SIGTERM, sendsig); | |
4a31bc6f BJ |
133 | pid = fork(); |
134 | if (pid < 0) { | |
135 | perror("fork"); | |
136 | exit(1); | |
137 | } | |
138 | ioctl(rfd2, FIONBIO, &one); | |
139 | ioctl(rem, FIONBIO, &one); | |
140 | if (pid == 0) { | |
141 | char *bp; int rembits, wc; | |
142 | (void) close(rfd2); | |
143 | reread: | |
420d8a52 | 144 | errno = 0; |
4a31bc6f BJ |
145 | cc = read(0, buf, sizeof buf); |
146 | if (cc <= 0) | |
147 | goto done; | |
148 | bp = buf; | |
149 | rewrite: | |
150 | rembits = 1<<rem; | |
e7d6d17a SL |
151 | if (select(16, 0, &rembits, 0, 0) < 0) { |
152 | if (errno != EINTR) { | |
153 | perror("select"); | |
154 | exit(1); | |
155 | } | |
156 | goto rewrite; | |
157 | } | |
4a31bc6f BJ |
158 | if ((rembits & (1<<rem)) == 0) |
159 | goto rewrite; | |
160 | wc = write(rem, bp, cc); | |
161 | if (wc < 0) { | |
162 | if (errno == EWOULDBLOCK) | |
163 | goto rewrite; | |
164 | goto done; | |
165 | } | |
166 | cc -= wc; bp += wc; | |
167 | if (cc == 0) | |
168 | goto reread; | |
169 | goto rewrite; | |
170 | done: | |
420d8a52 | 171 | (void) shutdown(rem, 1); |
4a31bc6f BJ |
172 | exit(0); |
173 | } | |
4ca10280 | 174 | sigsetmask(omask); |
4a31bc6f BJ |
175 | readfrom = (1<<rfd2) | (1<<rem); |
176 | do { | |
177 | ready = readfrom; | |
e7d6d17a SL |
178 | if (select(16, &ready, 0, 0, 0) < 0) { |
179 | if (errno != EINTR) { | |
180 | perror("select"); | |
181 | exit(1); | |
182 | } | |
183 | continue; | |
184 | } | |
4a31bc6f BJ |
185 | if (ready & (1<<rfd2)) { |
186 | errno = 0; | |
187 | cc = read(rfd2, buf, sizeof buf); | |
188 | if (cc <= 0) { | |
189 | if (errno != EWOULDBLOCK) | |
190 | readfrom &= ~(1<<rfd2); | |
191 | } else | |
192 | (void) write(2, buf, cc); | |
193 | } | |
194 | if (ready & (1<<rem)) { | |
195 | errno = 0; | |
196 | cc = read(rem, buf, sizeof buf); | |
197 | if (cc <= 0) { | |
198 | if (errno != EWOULDBLOCK) | |
199 | readfrom &= ~(1<<rem); | |
200 | } else | |
201 | (void) write(1, buf, cc); | |
202 | } | |
203 | } while (readfrom); | |
204 | (void) kill(pid, SIGKILL); | |
205 | exit(0); | |
206 | usage: | |
207 | fprintf(stderr, | |
208 | "usage: rsh host [ -l login ] [ -p passwd ] command\n"); | |
209 | exit(1); | |
210 | } | |
211 | ||
4a31bc6f BJ |
212 | sendsig(signo) |
213 | int signo; | |
214 | { | |
215 | ||
216 | (void) write(rfd2, (char *)&signo, 1); | |
217 | } |