From ade6a8566204bb4334861c9fbfc1b5c933d1e9f9 Mon Sep 17 00:00:00 2001 From: Benjamin Franzke Date: Sat, 12 Nov 2011 13:58:31 +0100 Subject: Implement pjlink authentication --- configure.ac | 3 +- src/Makefile.am | 4 +- src/pjctl.c | 126 ++++++++++++++++++++++++++++++++++++++++++++++---------- 3 files changed, 108 insertions(+), 25 deletions(-) diff --git a/configure.ac b/configure.ac index 467fb9a..f81cc9f 100644 --- a/configure.ac +++ b/configure.ac @@ -16,7 +16,8 @@ m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])]) # Check for programs AC_PROG_CC -#PKG_PROG_PKG_CONFIG() +PKG_PROG_PKG_CONFIG() +PKG_CHECK_MODULES(crypto, [libcrypto]) if test "x$GCC" = "xyes"; then GCC_CFLAGS="-Wall -g -Wstrict-prototypes -Wmissing-prototypes -fvisibility=hidden" diff --git a/src/Makefile.am b/src/Makefile.am index c3bb4c5..42f568a 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -2,7 +2,7 @@ bin_PROGRAMS = pjctl pjctl_SOURCES = pjctl.c -pjctl_LDADD = $(GLIB_LIBS) $(GIO_LIBS) -AM_CPPFLAGS = $(GLIB_CFLAGS) $(GIO_CFLAGS) +pjctl_LDADD = $(crypto_LIBS) +AM_CPPFLAGS = $(crypto_CFLAGS) AM_CFLAGS = $(GCC_CFLAGS) diff --git a/src/pjctl.c b/src/pjctl.c index 0b444f2..22d9293 100644 --- a/src/pjctl.c +++ b/src/pjctl.c @@ -17,7 +17,7 @@ * along with this program. If not, see . */ -#define _POSIX_C_SOURCE 1 +#define _POSIX_C_SOURCE 2 #define _GNU_SOURCE #include @@ -30,6 +30,8 @@ #include #include +#include + enum pjlink_packet_offsets { PJLINK_HEADER = 0, PJLINK_CLASS = 1, @@ -42,6 +44,7 @@ enum pjlink_packet_offsets { enum pjctl_state { PJCTL_AWAIT_INITIAL, PJCTL_AWAIT_RESPONSE, + PJCTL_AWAIT_RESPONSE_OR_AUTH_ERR, PJCTL_FINISH }; @@ -59,6 +62,10 @@ struct pjctl { enum pjctl_state state; struct queue_command queue; int fd; + + char *password; + int need_hash; + char hash[32+1]; /* 0-terminated hex as ascii encoded 16 byte hash */ }; #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0])) @@ -113,11 +120,33 @@ handle_pjlink_error(char *param) return 0; } +static void +init_hash(struct pjctl *pjctl, const char *salt) +{ + unsigned char md[MD5_DIGEST_LENGTH]; + MD5_CTX md5; + + MD5_Init(&md5); + MD5_Update(&md5, salt, strlen(salt)); + MD5_Update(&md5, pjctl->password, strlen(pjctl->password)); + MD5_Final(md, &md5); + + snprintf(pjctl->hash, sizeof(pjctl->hash), + "%02x%02x%02x%02x%02x%02x%02x%02x" + "%02x%02x%02x%02x%02x%02x%02x%02x", + md[ 0], md[ 1], md[ 2], md[ 3], + md[ 4], md[ 5], md[ 6], md[ 7], + md[ 8], md[ 9], md[10], md[11], + md[12], md[13], md[14], md[15]); + pjctl->need_hash = 1; +} + static int send_next_cmd(struct pjctl *pjctl) { - ssize_t ret; struct queue_command *cmd; + struct msghdr msg; + struct iovec iov[2]; /* Are we're ready? */ if (pjctl->queue.next == &pjctl->queue) { @@ -125,11 +154,28 @@ send_next_cmd(struct pjctl *pjctl) return 0; } - cmd = pjctl->queue.prev; + pjctl->state = PJCTL_AWAIT_RESPONSE; - ret = send(pjctl->fd, cmd->command, strlen(cmd->command), 0); + memset(&msg, 0, sizeof msg); + msg.msg_iov = iov; - pjctl->state = PJCTL_AWAIT_RESPONSE; + if (pjctl->need_hash) { + pjctl->state = PJCTL_AWAIT_RESPONSE_OR_AUTH_ERR; + + iov[msg.msg_iovlen].iov_base = pjctl->hash; + iov[msg.msg_iovlen].iov_len = 32; + msg.msg_iovlen++; + } + + cmd = pjctl->queue.prev; + iov[msg.msg_iovlen].iov_base = cmd->command; + iov[msg.msg_iovlen].iov_len = strlen(cmd->command); + msg.msg_iovlen++; + + if (sendmsg(pjctl->fd, &msg, 0) < 0) { + fprintf(stderr, "sendmsg failed: %m\n"); + return -1; + } return 0; } @@ -137,20 +183,36 @@ send_next_cmd(struct pjctl *pjctl) static int handle_setup(struct pjctl *pjctl, char *data, int len) { - if (data[PJLINK_PARAMETER] == '1') { - fprintf(stderr, - "error: pjlink encryption is not implemented.\n"); - return -1; - } - - if (data[PJLINK_PARAMETER] != '0') { - fprintf(stderr, "error: invalid setup message received.\n"); - return -1; + switch (data[PJLINK_PARAMETER]) { + case '1': + if (pjctl->password == NULL) { + fprintf(stderr, + "Authentication required, password needed\n"); + return -1; + } + if (strlen(&data[PJLINK_PARAMETER]) < 3) + goto err; + init_hash(pjctl, &data[PJLINK_PARAMETER+2]); + break; + case '0': + /* No authentication */ + break; + case 'E': + if (strcmp(&data[PJLINK_PARAMETER], "ERRA") == 0) { + fprintf(stderr, "Authentication failed.\n"); + return -1; + } + /* FALLTHROUGH */ + default: + goto err; } send_next_cmd(pjctl); return 0; +err: + fprintf(stderr, "error: invalid setup message received.\n"); + return -1; } static int @@ -164,14 +226,22 @@ handle_data(struct pjctl *pjctl, char *data, int len) } if (strncmp(data, "PJLINK ", 7) == 0) { - if (pjctl->state != PJCTL_AWAIT_INITIAL) { + switch (pjctl->state) { + case PJCTL_AWAIT_INITIAL: + case PJCTL_AWAIT_RESPONSE_OR_AUTH_ERR: + break; + default: fprintf(stderr, "error: got unexpected initial\n"); return -1; } return handle_setup(pjctl, data, len); } - if (pjctl->state != PJCTL_AWAIT_RESPONSE) { + switch (pjctl->state) { + case PJCTL_AWAIT_RESPONSE: + case PJCTL_AWAIT_RESPONSE_OR_AUTH_ERR: + break; + default: fprintf(stderr, "error: got unexpected response.\n"); return -1; } @@ -590,7 +660,7 @@ usage(struct pjctl *pjctl) { int i; - printf("usage: pjctl command [args..]\n\n"); + printf("usage: pjctl [-p password] command [args..]\n\n"); printf("commands:\n"); for (i = 0; i < ARRAY_SIZE(commands); ++i) printf(" %s %s\n", commands[i].name, commands[i].help); @@ -600,22 +670,33 @@ int main(int argc, char **argv) { struct pjctl pjctl; - char *host = argv[1]; + char *host; char *sport = "4352"; struct addrinfo hints, *result, *rp; - int s, i; + int s, i, c; memset(&pjctl, 0, sizeof pjctl); pjctl.queue.next = pjctl.queue.prev = &pjctl.queue; - if (argc <= 2) { + while ((c = getopt(argc, argv, "p:")) != -1) { + switch (c) { + case 'p': + pjctl.password = optarg; + break; + default: + return 1; + } + } + + if (argc < optind+2) { usage(&pjctl); return 1; } for (i = 0; i < ARRAY_SIZE(commands); ++i) { - if (strcmp(argv[2], commands[i].name) == 0) { - if (commands[i].func(&pjctl, &argv[2], argc-2) < 0) + if (strcmp(argv[optind+1], commands[i].name) == 0) { + if (commands[i].func(&pjctl, &argv[optind+1], + argc-optind-1) < 0) return 1; } } @@ -631,6 +712,7 @@ main(int argc, char **argv) hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; + host = argv[optind]; s = getaddrinfo(host, sport, &hints, &result); if (s != 0) { fprintf(stderr, "getaddrinfo :%s\n", gai_strerror(s)); -- cgit