-
Notifications
You must be signed in to change notification settings - Fork 0
/
setup-ssh-agent
128 lines (113 loc) · 4.34 KB
/
setup-ssh-agent
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
#!/bin/sh
# Hey EMACS, this should be in -*- sh -*- mode
#
# This starts ssh-agent in a predictable location if it's not already configured
# The location is ${HOME}/.ssh/agents/${HOSTNAME}
#
# To use this script you must source it so that the environment variable SSH_AUTH_SOCK can be set
# This is best done from your bashrc
# if [ -e "${HOME}"/.ssh/setup-ssh-agent ]; then
# source "${HOME}"/.ssh/setup-ssh-agent
# fi
debug() { ! "${log_debug-false}" || log "DEBUG: $*" >&2; }
log() { printf '%s\n' "$*"; }
warn() { log "WARNING: $*" >&2; }
error() { log "ERROR: $*" >&2; }
try() { "$@" || error "'$@' failed"; }
# Canonicalize hostname to just the short name
if [ -z "${HOSTNAME}" ]; then
HOSTNAME=$(hostname)
fi
HOSTNAME=$(echo ${HOSTNAME} | sed 's/\..*//')
SOCKET_FILENAME="${HOME}"/.ssh/agents/${HOSTNAME}
# start agent if instructed to
start_agent() {
if [ -e "${HOME}/.ssh/.start-ssh-agent" ]; then
debug "Starting agent with ${SOCKET_FILENAME}"
try mkdir -p "${HOME}"/.ssh/agents
# remove any existing socket that might be left over
try rm -f "${SOCKET_FILENAME}"
try ssh-agent -a "${SOCKET_FILENAME}" > /dev/null 2>&1
SSH_AUTH_SOCK="${SOCKET_FILENAME}"
export SSH_AUTH_SOCK
debug "agent started"
else
debug "Agent not started due to user request"
fi
}
if [ -z "${SSH_AUTH_SOCK}" ]; then
debug "No socket variable defined"
if [ -e "${SOCKET_FILENAME}" ]; then
debug "Attempting to use existing socket at '${SOCKET_FILENAME}'"
SSH_AUTH_SOCK="${SOCKET_FILENAME}"
export SSH_AUTH_SOCK
fi
fi
# check if SOCKET_FILENAME is valid, if so use it
# this assumes that the oldest valid socket is the one to keep
if [ -e "${SOCKET_FILENAME}" -a -n "${SSH_AUTH_SOCK}" ]; then
debug "Saving ${SSH_AUTH_SOCK} while testing ${SOCKET_FILENAME}"
ORIG_SSH_AUTH_SOCK=${SSH_AUTH_SOCK}
export ORIG_SSH_AUTH_SOCK
debug "Attempting to use existing socket at '${SOCKET_FILENAME}'"
SSH_AUTH_SOCK="${SOCKET_FILENAME}"
export SSH_AUTH_SOCK
# check if the socket is valid
output=$(timeout 2s ssh-add -l 2>&1)
ssh_add_status=$?
debug "ssh-add status ${ssh_add_status}"
debug "ssh-add output '${output}'"
if [ ${ssh_add_status} -eq 0 -o "${output#The agent has no identities}" != "${output}" ]; then
debug "Valid SSH socket at '${SSH_AUTH_SOCK}'"
else
debug "Socket at '${SSH_AUTH_SOCK}' is not valid using '${ORIG_SSH_AUTH_SOCK}'"
SSH_AUTH_SOCK=${ORIG_SSH_AUTH_SOCK}
export SSH_AUTH_SOCK
fi
fi
if [ -z "${SSH_AUTH_SOCK}" -a -n "${ORIG_SSH_AUTH_SOCK}" ]; then
SSH_AUTH_SOCK=${ORIG_SSH_AUTH_SOCK}
export SSH_AUTH_SOCK
fi
if [ -n "${SSH_AUTH_SOCK}" ]; then
debug "Socket variable is defined as ${SSH_AUTH_SOCK}"
# check if the socket is valid
output=$(timeout 2s ssh-add -l 2>&1)
ssh_add_status=$?
debug "ssh-add status ${ssh_add_status}"
debug "ssh-add output '${output}'"
if [ ${ssh_add_status} -eq 0 -o "${output#The agent has no identities}" != "${output}" ]; then
debug "Valid SSH socket at '${SSH_AUTH_SOCK}'"
if [ "${SSH_AUTH_SOCK}" != "${SOCKET_FILENAME}" ]; then
debug "Valid socket is not in the expected location, setting symlink and environment variable"
ln -sf "${SSH_AUTH_SOCK}" "${SOCKET_FILENAME}"
SSH_AUTH_SOCK="${SOCKET_FILENAME}"
export SSH_AUTH_SOCK
fi
elif [ -n "${ORIG_AUTH_SOCK}" ]; then
debug "${SSH_AUTH_SOCK} is invalid trying ${ORIG_AUTH_SOCK}"
SSH_AUTH_SOCK=${ORIG_SSH_AUTH_SOCK}
export SSH_AUTH_SOCK
output=$(timeout 2s ssh-add -l 2>&1)
ssh_add_status=$?
debug "ssh-add status ${ssh_add_status}"
debug "ssh-add output '${output}'"
if [ ${ssh_add_status} -eq 0 -o "${output#The agent has no identities}" != "${output}" ]; then
debug "Valid SSH socket at '${SSH_AUTH_SOCK}'"
else
debug "Invalid SSH socket at '${SSH_AUTH_SOCK}', clearing"
unset SSH_AUTH_SOCK
unset ORIG_SSH_AUTH_SOCK
start_agent
fi
else
debug "Invalid SSH socket at '${SSH_AUTH_SOCK}', clearing"
unset SSH_AUTH_SOCK
start_agent
fi
else
debug "No socket defined, starting agent"
start_agent
fi
# cleanup
unset SOCKET_FILENAME