diff options
| -rw-r--r-- | laim.c | 291 |
1 files changed, 200 insertions, 91 deletions
@@ -1,14 +1,15 @@ -// laim (0.2.5): a lame mail server -// connect to a --boot laim with `ncat --ssl <address> <port>` (requires nmap) -// or `nc <address> <port>` if not running under SSL (requires netcat or a busybox with the nc applet built) +// laim (0.2.6b): a lame mail server // -// originally created by Moon Flower Fields (https://coffin.ir/) or @moonflowerfields on Telegram +// creator: moon flower fields +// website: coffin.ir +// telegram: @moonflowerfields // very funny. #define COMEDIAN false -#define SZ 128 -#define EOF -1 +#define SZ 128 +#define EOF -1 +#define max_targets 16 #include <fcntl.h> #include <stdint.h> @@ -103,15 +104,31 @@ int get_char() { char *glob_buf = NULL; u64 glob_sz = 0; -// clang-format off -void sadd(cstr s) { char *prev = glob_buf; while (*s) *glob_buf++ = *s++; glob_sz += glob_buf - prev; } +void sadd(cstr s) { + char *prev = glob_buf; + while (*s) *glob_buf++ = *s++; + glob_sz += glob_buf - prev; +} #define over __attribute__((overloadable)) void -over sit(char *p, cstr s) { glob_buf = p; glob_sz = 0; sadd(s); } -over sit(char *p, cstr s, cstr s2) { sit(p, s); sadd(s2); } -over sit(char *p, cstr s, cstr s2, cstr s3) { sit(p, s); sadd(s2); sadd(s3); } +over sit(char *p, cstr s) { + glob_buf = p; + glob_sz = 0; + sadd(s); +} +over sit(char *p, cstr s, cstr s2) { + sit(p, s); + sadd(s2); +} +over sit(char *p, cstr s, cstr s2, cstr s3) { + sit(p, s); + sadd(s2); + sadd(s3); +} -void memzero(char *s, u64 len) { for (u64 i = 0; i < len; i++) s[ i ] = 0; } +void memzero(char *s, u64 len) { + for (u64 i = 0; i < len; i++) s[ i ] = 0; +} void nadd(u64 n) { if (!n) { @@ -130,8 +147,11 @@ void nadd(u64 n) { glob_buf += len; glob_sz += len; } -void nlod(char *p, u64 n) { glob_buf = p; glob_sz = 0; nadd(n); } -// clang-format on +void nlod(char *p, u64 n) { + glob_buf = p; + glob_sz = 0; + nadd(n); +} void print_u64(u64 n) { static char tmp[ 21 ] = { 0 }; @@ -156,6 +176,18 @@ u64 scan_u64() { return n; } +u64 scan_u64_fd(int fd) { + if (fd == STDIN_FILENO) return scan_u64(); // avoid buffer skips + + u64 n = 0; + char c; + while (read(fd, &c, 1) == 1) { + if (c < '0' || c > '9') break; + n = n * 10 + (c - '0'); + } + return n; +} + long syscall(long number, ...); u64 now() { @@ -182,7 +214,6 @@ u64 room_user_count(char *room_path) { int fd = openat(dir_fd, d->d_name, O_RDONLY); if (fd >= 0) { if (flock(fd, LOCK_EX | LOCK_NB) == 0) { - // dead owner flock(fd, LOCK_UN); unlinkat(dir_fd, d->d_name, 0); } else { @@ -224,7 +255,7 @@ void list_users(int dir_fd, bool rooms) { print_u64(ts); close(login_fd); } else { - writes(" 0\n"); + writes("0"); } } writes("\n"); @@ -245,7 +276,7 @@ void sopen(int fd) { flock(fd, LOCK_UN); } }) void printmail(char path[ SZ ], u64 after) { - mkdir(path, 0700); // make it if it doesnt exist + mkdir(path, 0700); int dir_fd = open(path, O_RDONLY | O_DIRECTORY); if (dir_fd < 0) return; @@ -273,21 +304,8 @@ void printmail(char path[ SZ ], u64 after) { continue; } - u64 ts = 0; - char tsbuf[ 21 ]; - u64 n = read(mail_fd, tsbuf, sizeof(tsbuf) - 1); - if (n <= 0) { - close(mail_fd); - continue; - } - tsbuf[ n ] = 0; - for (u64 j = 0; j < n; j++) { - if (tsbuf[ j ] >= '0' && tsbuf[ j ] <= '9') ts = ts * 10 + (tsbuf[ j ] - '0'); - else { - lseek(mail_fd, j - n, SEEK_CUR); - break; - } - } + u64 ts = scan_u64_fd(mail_fd); + u64 expiry = scan_u64_fd(mail_fd); if (ts < after) { close(mail_fd); @@ -300,13 +318,18 @@ void printmail(char path[ SZ ], u64 after) { writeb(header, ++glob_sz); nlod(header, ts); writeb(header, glob_sz); + writes("\n"); static char buf[ 256 ]; int r; while ((r = read(mail_fd, buf, sizeof(buf))) > 0) writeb(buf, r); writes("\n\neof\n"); + close(mail_fd); + + // expired goods. + if (expiry != 0 && expiry < now()) unlinkat(dir_fd, name, 0); } close(dir_fd); } @@ -341,18 +364,30 @@ const char makefile[] = { , 0 }; -// used for both passwords and usernames. -// not my fault if you wanna use a weird pass. bool is_path_char(char c) { return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '-' || c == '_' || c == '.' || c == ' ' || c == '$' || c == ':'; } +int field_sep = -1; +bool field_more = false; + #define read_field(buf, err, fail_action, len_buf) \ ({ \ bool _term = false; \ + field_more = false; \ for (u8 _i = 0; _i < 64; _i++) { \ int _ch = get_char(); \ + if (_ch == field_sep) { \ + (buf)[ _i ] = 0; \ + _term = true; \ + field_more = true; \ + if (len_buf != NULL) { \ + u8 *ptr = len_buf; \ + *ptr = _i; \ + } \ + break; \ + } \ if (_ch == '\n' || _ch == EOF) { \ (buf)[ _i ] = 0; \ _term = true; \ @@ -374,7 +409,7 @@ bool is_path_char(char c) { } \ }) -// timing safe or whatever. +// timing safe bool safe_cmp(char *left, char *right, u64 size) { bool nonmatch = false; bool ended = false; @@ -428,6 +463,73 @@ void leave_room() { ephemeral = false; } +bool sendmail(char *user, u8 userlen, char *target, char *body, u64 body_len, u64 expiry) { + char dest_path[ SZ ] = { 0 }; + sit(dest_path, "mail/", target, "/"); + mkdir(dest_path, 0700); + + int dir_fd = open(dest_path, O_RDONLY | O_DIRECTORY); + if (dir_fd < 0) { + writes("err:dir\n"); + return false; + } + slock(dir_fd); + + u64 index = create_index(dir_fd); + if (index == -1) { + writes("!"); + sopen(dir_fd); + close(dir_fd); + return false; + } + sit(dest_path, "mail/", target, "/"); + nadd(index); + + int user_fd = smake(dest_path); + if (user_fd < 0) { + sopen(dir_fd); + close(dir_fd); + writes("err:smake\n"); + return false; + } + slock(user_fd); + sopen(dir_fd); + close(dir_fd); + + char *ts = str_u64(now()); + write(user_fd, ts, lenstr(ts)); + write(user_fd, "\n", 1); + char *ex = str_u64(expiry); + write(user_fd, ex, lenstr(ex)); + write(user_fd, "\n", 1); + write(user_fd, user, userlen); + write(user_fd, "\n", 1); + write(user_fd, body, body_len); + + sopen(user_fd); + close(user_fd); + + return true; +} + +char *read_body(u64 *body_len_out) { + static char body[ 65536 ]; + u64 body_len = 0; + char buf[ 256 ] = { 0 }; + int read_size; + while ((read_size = readn(buf, sizeof(buf))) > 0) { + if (body_len + read_size > sizeof(body)) { + writes("."); + *body_len_out = 0; + return NULL; + } + memcopy(body + body_len, buf, read_size); + body_len += read_size; + } + *body_len_out = body_len; + return body; +} + int main(int argc, char **argv) { char path[ 4096 ] = { 0 }; { u64 bye = readlink("/proc/self/exe", path, sizeof(path) - 1); } @@ -507,6 +609,22 @@ laim_start:; memcopy(user_path + 6, user, userlen); user_path[ 6 + userlen ] = 0; + // check lastlogin before sleeping + char last_login[ SZ ] = { 0 }; + sit(last_login, "mail/", user, "/.login"); + *glob_buf = 0; + { + int login_fd = open(last_login, O_RDONLY); + u64 old_ts = 0, old_pid = 0; + if (login_fd >= 0) { + read(login_fd, &old_ts, 8); + read(login_fd, &old_pid, 8); + close(login_fd); + } + if (old_pid > 0) syscall(62, old_pid, 9); // kill old + if (now() - old_ts < 5) sleep(1); // fly swatter + } + if (access(user_path, F_OK) != 0) { writes("N"); goto laim_start; @@ -544,8 +662,10 @@ laim_start:; int login_fd = open(last_login, O_RDWR | O_CREAT, 0600); if (login_fd >= 0) { ftruncate(login_fd, 0); - u64 ts = now(); - write(login_fd, &ts, 8); + u64 ts = now(); + u64 pid = syscall(39); // getpid + write(login_fd, &ts, 8); + write(login_fd, &pid, 8); close(login_fd); } } @@ -569,6 +689,7 @@ laim_start:; int _c; while ((_c = get_char()) != EOF) { + field_sep = -1; if (_c == '\n') continue; char c = _c; if (c == 'G') { // get all mail @@ -639,69 +760,57 @@ laim_start:; } list_users(dir_fd, c == 'R'); close(dir_fd); + writes("O"); } else if (c == 'T') { // get mail after X printmail(filename, scan_u64()); - } else if (c == 'S') { // send mail - char target[ SZ ]; - read_field(target, "7", goto while_end, NULL); - - char dest_path[ SZ ] = { 0 }; - sit(dest_path, "mail/", target, "/"); - mkdir(dest_path, 0700); - - int dir_fd = open(dest_path, O_RDONLY | O_DIRECTORY); - if (dir_fd < 0) { - writes("err:dir\n"); - continue; + writes("O"); + } else if (c == 'S') { + char targets[ max_targets ][ SZ ]; + u8 target_count = 0; + + field_sep = ','; + field_more = true; + while (field_more && target_count < max_targets) { + read_field(targets[ target_count ], "7", goto while_end, NULL); + if (targets[ target_count ][ 0 ]) target_count++; } - slock(dir_fd); + field_sep = -1; + + u64 body_len; + char *body = read_body(&body_len); + if (!body) goto while_end; // limit - u64 index = create_index(dir_fd); - if (index == -1) { + for (u8 i = 0; i < target_count; i++) { + if (sendmail(user, userlen, targets[ i ], body, body_len, 0)) continue; writes("!"); - sopen(dir_fd); - close(dir_fd); - continue; + goto while_end; } - sit(dest_path, "mail/", target, "/"); - nadd(index); - - int user_fd = smake(dest_path); - if (user_fd < 0) { - sopen(dir_fd); - close(dir_fd); - writes("err:smake\n"); - continue; + writes("O"); + } else if (c == 'H') { // perishable post + char targets[ max_targets ][ SZ ]; + u8 target_count = 0; + + field_sep = ','; + field_more = true; + while (field_more && target_count < max_targets) { + read_field(targets[ target_count ], "7", goto while_end, NULL); + if (targets[ target_count ][ 0 ]) target_count++; } - slock(user_fd); - sopen(dir_fd); - close(dir_fd); + field_sep = -1; - char *ts = str_u64(now()); - write(user_fd, ts, lenstr(ts)); - write(user_fd, "\n", 1); - write(user_fd, user, userlen); - write(user_fd, "\n", 1); - - bool hit_limit = false; - - u64 total_size = 0; - char buf[ 256 ] = { 0 }; - int read_size; - while ((read_size = readn(buf, sizeof(buf))) > 0) { - write(user_fd, buf, read_size); - total_size += read_size; - if (total_size > 65536) { - hit_limit = true; - writes("."); - break; - } - } + u64 ttl = scan_u64(); + u64 expiry = ttl ? now() + ttl : 0; - if (!hit_limit) writes("O"); + u64 body_len; + char *body = read_body(&body_len); + if (!body) goto while_end; // limit - sopen(user_fd); - close(user_fd); + for (u8 i = 0; i < target_count; i++) { + if (sendmail(user, userlen, targets[ i ], body, body_len, expiry)) continue; + writes("!"); + goto while_end; + } + writes("O"); } else if (c == 'D') { // delete mail u64 index = scan_u64(); @@ -717,7 +826,7 @@ laim_start:; read_field(newpass2, "7", goto while_end, &passlen2); if (passlen != passlen2) err("K"); - if (safe_cmp(newpass, newpass2, passlen)) err("K"); + if (!safe_cmp(newpass, newpass2, passlen)) err("K"); char user_path[ SZ ] = "users/"; memcopy(user_path + 6, user, userlen); |